pleistocene palaeoecology of the eastern darling downs · darling downs, southeastern queensland,...
TRANSCRIPT
SCHOOL OF NATURAL RESOURCE SCIENCE
QUEENSLAND UNIVERSITY OF TECHNOLOGY
Pleistocene Palaeoecology of the Eastern Darling Downs
by
Gilbert J. Price
BAppSc (Hons) Ecology
2006
Queensland University of Technology
Supervisors
Gregory E. Webb
Bernard N. Cooke
Submitted in fulfillment of the requirements for the degree
Doctor of Philosophy
“From the Condamine River, the country rises very gently, almost
imperceptibly, till the road passes between two hills of ranges, when the
basaltic rock re-appears again. Very extensive shallow valleys or plains,
generally with a creek, overgrown with reeds, covered with rich high grass,
were spread before my eyes, when I had passed these hills, the right of
which goes under the name of Rubieslaw, and the left under that of Sugar-
loaf... All this country, from the Condamine to the range, is called the
DARLING DOWNS. There is no equal to them all over the colony...”
Ludwig Leichhardt, 23 June, 1843.
Leichhardt, W.F.L. 1843. Journal (28/12/1842 - 24/07/1843). Handwritten
manuscripts in the Mitchell Library, Sydney.
ABSTRACT
Several late Pleistocene fossil localities in the Kings Creek catchment,
Darling Downs, southeastern Queensland, Australia, were examined in detail
to establish an accurate, dated palaeoecological record for the region, and to
test human versus climate change megafauna extinction hypotheses.
Accelerator Mass Spectrometry (AMS 14C) and U/Th dating confirm that the
deposits are late Pleistocene in age, but the dates obtained from the two
methods are not in agreement. Fluvial depositional accumulation processes
in the catchment reflect both high-energy channel and low-energy episodic
overbank deposition. The most striking taphonomic observations for
vertebrates in the deposits include: 1) low representation of post-cranial
elements; 2) high degree of bone breakage; 3) variable abrasion but most
identifiable bone elements with low to moderate degree of abrasion; 4) low
rates of bone weathering; 5) low degree of carnivore bone modification; and
6) low degree of articulated or associated specimens. Collectively, those
data suggest that the material was transported into the deposit from the
surrounding proximal floodplain and that the assemblages reflect hydraulic
sorting. A multifaceted palaeoecological investigation revealed significant
habitat change between superposed assemblages of site QML796. The
basal fossiliferous unit contained species that indicate the presence of a
mosaic of habitats including riparian vegetation, vine thickets, scrubland,
open and closed woodlands, and open grasslands during the late
Pleistocene. Those woody and scrubby habitats contracted over the period
of deposition so that by the time of deposition of the youngest horizon, the
creek sampled a more open type environment. Sequential faunal horizons
show a step-wise decrease in taxonomic diversity that cannot be explained
by sampling or taphonomic bias. The decreasing diversity includes loss of
some, but not all, megafauna and is consistent with a progressive local loss
of megafauna in the catchment over an extended interval of time.
Collectively, those data are consistent with a climatic cause of megafauna
extinction, and no specific evidence was found to support human
involvement in the local extinctions. Better dating of the deposits is critically
important, as a secure chronology would have significant implications
regarding the continent-wide extinction of the Australian megafauna.
KEY WORDS: fluvial sedimentology, taphonomy, megafauna
extinction, climate change, Pleistocene, Darling Downs, Australia.
LIST OF PUBLICATIONS / SUBMITTED MANUSCRIPTS
PRICE, G.J. 2002. Perameles sobbei sp. nov. (Marsupialia, Peramelidae), a
Pleistocene bandicoot from the Darling Downs, south-eastern
Queensland. Memoirs of the Queensland Museum. 48: 193-197.
PRICE, G.J. 2005 (2004)a. Fossil bandicoots (Marsupialia, Peramelidae) and
environmental change during the Pleistocene on the Darling Downs,
southeastern Queensland, Australia. Journal of Systematic Palaeontology.
2: 347-356.
PRICE, G.J. 2005b. Pleistocene megafauna extinction: new evidence from the
Darling Downs, southeastern Queensland. Quaternary Australasia. 23(1):
15-16.
PRICE, G.J. & HOCKNULL, S.A. 2005. A small adult Palorchestes (Marsupialia,
Palorchestidae) from the Pleistocene of the Darling Downs, southeast
Queensland. Memoirs of the Queensland Museum. 51: 202.
PRICE, G.J., TYLER, M.J. & COOKE, B.N. 2005. Pleistocene frogs from the
Darling Downs, southeastern Queensland, Australia, and their
palaeonenvironmental significance. Alcheringa. 29: 171-182.
PRICE, G.J. & SOBBE, I.H. 2005. Pleistocene palaeoecology and
environmental change on the Darling Downs, southeastern Queensland,
Australia. Memoirs of the Queensland Museum. 51: 171-201.
PRICE, G.J. & WEBB, G.E. revised. Late Pleistocene sedimentology,
taphonomy and megafauna extinction on the Darling Downs, southeastern
Queensland, Australia. Australian Journal of Earth Sciences.
PRICE, G.J. submitted. Late Pleistocene ecosystem dynamics, habitat
change, and species extinction on the Darling Downs, southeastern
Queensland, Australia. Palaeogeography, Palaeoclimatology,
Palaeoecology.
CONTENTS
STATEMENT OF ORIGINAL AUTHORSHIP 13
ACKNOWLEDGEMENTS 14
INTRODUCTION 16
DESCRIPTION OF RESEARCH PROBLEM 16
OBJECTIVES OF STUDY 18
SPECIFIC AIMS OF STUDY 18
RESEARCH PROGRESSION 19
LITERATURE REVIEW 23
INTRODUCTION 23
PLEISTOCENE 25
MEGAFAUNAL EXTINCTION 27
Anthropogenic models of extinction 28
Blitzkrieg 28
Sitzkrieg 32
Hyperdisease 36
Climate models of extinction 37
Co-evolutionary disequilibrium model 38
Mosaic-nutrient model 39
Multicausal or ecological models of extinction 41
Keystone herbivore model 41
Self-organised instability 43
Chronologies 44
DARLING DOWNS 51
Geographical and geological settings 51
Palaeoecology 53
Kings Creek Catchment 54
Site QML796 55
Excavation 56
Stratigraphy, sedimentology and taphonomy 57
Palaeoecology 60
Dating 63
Correlation to other Kings Creek deposits 65
SUMMARY 65
PUBLISHED PAPERS / SUBMITTED MANUSCRIPTS 67
Paper 1. PRICE, G.J. 2005 (2004)a. Fossil bandicoots (Marsupialia,
Peramelidae) and environmental change during the Pleistocene on the
Darling Downs, southeastern Queensland, Australia. Journal of Systematic
Palaeontology. 2: 347-356 67
INTRODUCTION 69
GEOGRAPHY AND STRATIGRAPHY 69
MATERIALS AND METHODS 69
SYSTEMATIC PALAEONTOLOGY 70
DISCUSSION 74
ACKNOWLEDGEMENTS 76
REFERENCES 76
Paper 2. PRICE, G.J., TYLER, M.J. & COOKE, B.N. 2005. Pleistocene frogs from
the Darling Downs, southeastern Queensland, Australia, and their
palaeonenvironmental significance. Alcheringa. 29: 171-182 79
GEOGRAPHICAL AND GEOLOGICAL SETTINGS 82
MATERIALS AND METHODS 82
SYSTEMATIC PALAEONTOLOGY 83
DISCUSSION 86
ACKNOWLEDGEMENTS 89
REFERENCES 89
Paper 3. PRICE, G.J. & SOBBE, I.H. 2005. Pleistocene palaeoecology and
environmental change on the Darling Downs, southeastern Queensland,
Australia. Memoirs of the Queensland Museum. 51: 171-201 93
SETTING 95
METHODS 96
Sedimentology 96
Taphonomy 96
Fauna 97
Dating 98
RESULTS 98
Sedimentology 98
Taphonomy 99
SYSTEMATIC PALAEONTOLOGY 102
Ecological remarks 111
Molluscs 111
Amphibians 112
Reptiles 112
Marsupials 113
Rodents 114
DATING 114
DISCUSSION 114
Sedimentology 114
Taphonomic history of bones 115
Palaeoenvironmental interpretation 116
CONCLUSIONS 118
ACKNOWLEDGEMENTS 119
LITERATURE CITED 119
Paper 4. PRICE, G.J. & WEBB, G.E. in press. Late Pleistocene sedimentology,
taphonomy and megafauna extinction on the Darling Downs, southeastern
Queensland, Australia. Australian Journal of Earth Sciences 125
ABSTRACT 127
INTRODUCTION 127
SETTING 132
METHODS 133
Excavation and sedimentology 133
Taphonomic analysis 134
Faunal attributes 139
RESULTS 139
Sedimentology and stratigraphy 139
Interpretation 146
Stratigraphic correlation with Kings Creek 149
Bivalve taphonomy 150
Interpretation 150
Vertebrate taphonomy 151
Bone appearance 151
Faunal attributes 153
Skeletal part representation 158
Skeletal breakage 160
Carnivore modification 164
Abrasion and hydraulic sorting 165
Articulated and associated material 167
Taphonomic interpretation 169
Biases relating to faunal groups 170
Mortality profiles 174
Carnivore modification 175
Accumulation processes 176
DISCUSSION 178
CONCLUSION 180
ACKNOWLEDGEMENTS 181
REFERENCES 182
Paper 5. PRICE, G.J. submitted. Late Pleistocene ecosystem dynamics,
habitat change, and species extinction on the Darling Downs, southeastern
Queensland, Australia. Palaeogeography, Palaeoclimatology,
Palaeoecology 191
ABSTRACT 192
INTRODUCTION 193
DARLING DOWNS DEPOSITS 196
METHODS 198
Sampling procedure 198
Ecological analogies to modern habitats 198
Diversity estimates 201
Dating 203
RESULTS 205
Species 205
Ecological dynamics 211
Feeding adaptations 211
Locomotory adaptations 213
Life habits 214
Diversity 215
Dating the deposits 216
DISCUSSION 219
Palaeoecology 219
Habitat change 223
Dating and implications 228
CONCLUSIONS 232
ACKNOWLEDGEMENTS 233
REFERENCES 233
GENERAL DISCUSSION 243
SIGNIFICANCE OF STUDY 243
MEGAFAUNA EXTINCTION HYPOTHESES 246
Anthropogenic models 246
Blitzkreig / Overkill 246
Sitzkrieg 247
Hyperdisease 248
Climate models of extinction 249
Co-evolutionary disequilibrium model 249
Mosaic-nutrient model 250
Multicausal or ecological models of extinction 251
Keystone herbivore model 251
Self-organised instability 252
FUTURE DIRECTIONS 252
SUMMARY 255
CONCLUSIONS 257
REFERENCES 259
APPENDICES 307
Appendix 1. PRICE, G.J. 2002. Perameles sobbei sp. nov. (Marsupialia,
Peramelidae), a Pleistocene bandicoot from the Darling Downs, south-
eastern Queensland. Memoirs of the Queensland Museum. 48:
193-197 307
SYSTEMATIC PALAEONTOLOGY 308
Remarks 310
Affinities 310
ACKNOWLEDGEMENTS 311
LITERATURE CITED 312
Appendix 2. PRICE, G.J. & HOCKNULL, S.A. 2005. A small adult Palorchestes
(Marsupialia, Palorchestidae) from the Pleistocene of the Darling Downs,
southeast Queensland. Memoirs of the Queensland Museum. 51: 202 313
Appendix 3. PRICE, G.J. 2005b. Pleistocene megafauna extinction: new
evidence from the Darling Downs, southeastern Queensland. Quaternary
Australasia. 23(1): 15-16 315
STATEMENT OF ORIGINAL AUTHORSHIP
The work contained in this thesis has not been previously submitted for a
degree or diploma at any other higher education institution. To the best of my
knowledge and belief, the thesis contains no material previously published or
written by another person except where due reference has been made.
Signature:
Date:
13
ACKNOWLEDGEMENTS
First and foremost, my supervisor, Gregg Webb, must be thanked for his
encouragement and guidance throughout the course of my PhD. Although
Gregg's primary expertise lies in the world of fossil coral reefs, Gregg quickly
developed a love and passion for fossilised rodent jaws, and his input into
my project was paramount to its eventual completion.
Prior to my commencement at university, most of my formal training in
palaeontology was through watching reruns of ‘The Flintstones’ on television.
In time, Bernard Cooke took me on as an Honours student, and eventually
became co-supervisor of my PhD project. His dedication has played a major
role in my transformation from a raw ecology student, to palaeontologist.
Ian, Diane and Amy Sobbe are thanked for their support and generosity
throughout the course of this research. They opened their home, hearts and
refrigerator to me for which I will be forever grateful. Ian was always available
to dig fossils, discuss the latest happenings in palaeontology, and consume
the occasional beverage whenever the time called for it.
Scott Hocknull worked alongside me for the course of my PhD. His
enthusiasm, guidance, and helpful discussions over the occasional lunchtime
basketball game was of great value during the course of this research.
Jian-xin Zhao and Yue-xin Feng provided expertise relating to U/Th
dating, conducted U/Th dating analyses, and produced very exciting results.
Gary and Neville Ronfelt, Peter Dutaillis, and especially, Ian Sobbe and
Trevor Sutton are thanked for allowing free access to properties where fossil
deposits are located.
Alex Baynes, Walter Boles, Brendan Brooke, Trevor Clifford, Alex ‘Gut
Contents’ Cook, Mary Dettmann, Liz Reed, John Stanisic, Mike Tyler, and
Ian Williamson are thanked for assistance and/or critical discussions on
various aspects of Darling Downs palaeoenvironments. Additionally, Alex
Baynes, Henk Godthelp, Russ Graham, Dirk Megirian, Troy Myers, Liz Reed,
Ian Reid, Steve Wroe and several anonymous reviewers provided
constructive comments that greatly improved the quality of the published
manuscripts that came from this work.
14
Assistance in the preparation of fossil material, access to specimens
and/or resources was due to the assistance of Andrew Amey, Ricky Bell,
Phillip Colquhon, Alex ‘they call him Dr. Worm’ Cook, Loc Duong, Peter Jell,
Graham Jordan, Paul Hamilton, Scott Hocknull, Debra Lewis, Owen McCaw,
Matthew Ng, Susan Parfrey, all School of Natural Resource Sciences
administration staff, Luke Shipton, the Sobbe family, Kristen Spring, Paul
Tierney, Greg Todd, Doug and Margaret Turner, Stuart Watt and Warwick
State High School, Joanne Wilkinson, and 100’s of volunteers who gave
freely of their time.
Finally, Desmond and Jennifer Price are thanked for their love and
support over my whole life, particularly during the course of my university
studies.
AMS 14C dating by ANSTO was supported by AINSE Grants 02/013 and
03/123. U/Th dating by ACQUIRE (University of Queensland) was supported
by Australian Research Council Linkage Grant LP0453664. This research
was funded in part by both the Queensland University of Technology and the
Queensland Museum.
15
INTRODUCTION
DESCRIPTION OF RESEARCH PROBLEM
Debate concerning the extinction of the Australian Pleistocene megafauna
has become polarised in recent years. Causes for extinction have been
debated widely with climate change, human hunting and/or human induced
habitat change, or a combination of those factors being the dominant
hypotheses (for recent reviews see Horton, 2000; Barnosky et al., 2004b;
Wroe et al., 2004; Burney & Flannery, 2005). The lack of a spatially
constrained chronology for the extinction of individual species and for human
occupation renders many hypotheses almost impossible to test. Additional
deposits incorporating more complex and detailed ecological analyses and
dating at different regional scales are required to resolve issues relating to
megafauna extinction (O’Connell & Allen, 2004).
The Darling Downs, southeastern Queensland, Australia, is emerging as
an area of major significance in the understanding of late Pleistocene (i.e.,
post-penultimate glacial maximum) megafaunal extinction. It is one of the
most fossiliferous regions in Australia, with over 50 individual Pleistocene
megafauna-bearing fossil localities known in a small (16 000 km2)
geographic area (Molnar & Kurz, 1997). Perhaps most importantly, some of
the youngest known megafaunal remains in Ausrtalia have been recovered
from fluvial deposits in the region (Roberts et al., 2001a).
Despite the apparent significance of the Darling Downs Pleistocene
deposits and associated faunas, few studies have addressed specifically: 1)
aspects of dating; 2) stratigraphy; 3) sedimentology; 4) taphonomy; and 5)
palaeoecology. Other than two optical stimulated luminescence (OSL) dates
presented by Roberts et al. (2001a), there has been little analytical dating
attempted for other megafauna-bearing deposits in the region. Hence,
Darling Downs megafaunal chronologies are largely unknown. Gill (1978)
dated the Talgai hominid skull deposit (Dalrymple Creek, Darling Downs)
using radiocarbon methods and suggested that the deposit was late
Pleistocene. However, megafaunal remains were not recorded in the deposit,
16
and it is unknown whether humans and megafauna overlapped temporally
on the Pleistocene Darling Downs.
Stratigraphic and relative temporal relationships of most deposits in the
region are also poorly known. Previous stratigraphic nomenclature erected
for specific units (see Macintosh, 1967; Gill, 1978) is now considered to be
invalid (Baird, 1986; Molnar & Kurz, 1997). As stratigraphic, sedimentologic
and chronologic details of the deposits are unknown, the deposits of the
region cannot be correlated to each other with any degree of certainty.
Hence, precise stratigraphical, sedimentological and chronological
relationships between Darling Downs deposits and other Australian fossil
deposits remain unclear.
Taphonomic aspects of Darling Downs deposits also have been rarely
documented. Molnar et al. (1999) described general aspects of a deposit
(site QML783, “Ned’s Gully”) that contained articulated remains of
megafauna, but recognised that articulated fossils are rare in the region.
Hence, potential taphonomic biases of most other deposits are unknown,
and thus, provide another factor that limits the precision of all subsequent
palaeoecological interpretations and comparisons.
Pleistocene vertebrate faunas of the region appear to be extremely
diverse. Species lists are dominated by megafaunal taxa, such as
Diprotodon sp., Protemnodon sp., and Macropus titan (e.g., Molnar & Kurz,
1997). Pleistocene habitat reconstructions based on such taxa have led to
interpretations of expansive grasslands and woodlands (Bartholomai, 1976b;
Molnar & Kurz, 1997). However, past collecting in the region focused on the
recovery of large-sized taxa, with smaller forms being overlooked (Molnar
and Kurz, 1997). Small-sized species are more highly valued than large-
sized species in palaeoecological studies as they commonly yield more
precise resolution of habitat and climate data (Brothwell & Jones 1978;
Andrews 1990; Vigne & Valladas 1996). Therefore, previous Darling Downs
palaeoenvironmental interpretations are limited, because the smaller forms
are poorly known.
Darling Downs Pleistocene fossil deposits are particularly important as the
faunas may encompass the late Pleistocene extinction episode in eastern
Australia. Hence, studies of its local faunas, that combine dating, lithofacies,
17
depositional environment, taphonomic, and palaeoecologic analyses, may
help to elucidate causes for megafauna decline and extinction at local,
regional, and potentially continental scales.
OBJECTIVES OF STUDY
The primary objective of this study was to gain a better understanding of the
palaeoecology of the Pleistocene Darling Downs so as to allow the testing of
hypotheses relating to the extinction of the Australian megafauna. Crucial
aspects involved the documentation of depositional environments. Such
investigations incorporated aspects of stratigraphy, sedimentology,
taphonomy, and radiometric age dating. Additionally, palaeoecological
analyses focused on both large- and small-sized taxa that occur in the
deposits and built on the work of Bartholomai (1976b) and Molnar & Kurz
(1997). While Pleistocene fossil deposits are common throughout the entire
Darling Downs, the project was focused on deposits in the Kings Creek
catchment, southern Darling Downs. The Kings Creek catchment is well
constrained in terms of size and contain some of the most abundant and
fossiliferous deposits in the region. It is an ideally suited study area for
investigations of the Pleistocene environment of the eastern Darling Downs.
SPECIFIC AIMS OF STUDY
A project with such broad goals had several specific aims:
1) To standardise collecting practices in order to minimise bias in the
sampling of fossil material, i.e., to design and implement a method of
collecting that targeted both large and small-sized taxa equally.
2) To identify all recognisable fossil material recovered and place it within
specific taxonomic groupings. That analysis formed the basis for all
subsequent biostratigraphical comparisons and palaeoecological
interpretations.
3) To document lithostratigraphic relationships between fossil deposits in the
region. That involved stratigraphic analyses of several fossil deposits as well
as limited radiometric dating.
18
4) To examine potential sources of taphonomic bias within the fossil deposits
in the catchment, thus allowing faunal assemblages to be correlated and
compared with each other with relative degrees of confidence.
5) To gain greater control on palaeoecological aspects of the deposits. In
conjunction with lithfacies and taphonomic analyses, a multifaceted
approach that incorporated ecological analogues to modern species and
communities, and diversity indices, provided detailed information about
palaeoenvironments.
6) To accurately date the deposits. Dating was an important aspect of the
study. Dating assisted in providing a chronology of deposition, and that led to
the establishment of temporal chronologies for species. Dating, combined
with the stratigraphic investigation, helped reveal temporal relationships
between fossil deposits within the catchment, and allowed the deposits to be
correlated at regional and continental scales. Dating also supported
phylogenetic studies of taxa in the deposits.
RESEARCH PROGRESSION
This thesis was constructed so as to provide a clear and coherent guide to
the research progression and follows ‘thesis by publication’ guidelines set by
the Queensland University of Technology (QUT). The literature review
provides the setting for the research by detailing the current up-to-date view
on Pleistocene megafaunal extinctions. The review discusses megafaunal
extinctions in general, but with a focus on the Australian situation. The
extended review continues with the current state of knowledge of Darling
Downs fossil deposits and the methodology employed in the project. The
literature review, of necessity, replicated some literature cited in subsequent
chapters.
Five major papers are presented as individual chapters. The first major
paper (Paper 1) deals with fluvial sampling aspects of the Pleistocene Kings
Creek catchment and palaeoecological aspects of bandicoots recovered
from its deposits. Documentation of the geographic area sampled in
19
palaeoecological studies of fossil vertebrate deposits is rarely attempted,
primarily because it is difficult or impossible to determine the precise
geographical extent represented by samples. The geographical extent of
palaeodrainages is commonly poorly constrained, hence, fossil deposits in
fluvial settings may contain geographically mixed assemblages that include
both local faunas and material transported from varying distances. However,
in this paper, the geography of the modern Kings Creek catchment was used
as a constraint on the potential Pleistocene catchment size. Secondly, early
collecting during initial stages of this project recovered several taxa
previously unknown to have a fossil record in the Pleistocene Darling Downs.
Among those taxa were new records of extant bandicoots and a previously
undescribed fossil bandicoot species (see Appendix 1: Price, 2002).
Palaeoenvironmental interpretations were based on analogy using extant
bandicoots, and hypotheses regarding late Pleistocene habitats and climates
are presented. The palaeoenvironmental interpretations are strengthened
because the size of the geographic area being sampled is well constrained.
Following on from the first paper, the second major paper (Paper 2)
discusses palaeoevnvironmental aspects of the Darling Downs based on
fossil frog assemblages. Small-sized taxa such as frogs and bandicoots are
ideal environmental indicators. Like most small-sized taxa, frogs and
bandicoots generally have small home ranges, specific habitat requirements,
and short life spans. Those ecological and biological traits make them more
useful for habitat reconstructions than many larger-sized taxa. Additionally,
frogs have permeable skins, and multiple life stages, and their value as
environmental bio-indicators is well known. Hence, detailed information
regarding Darling Downs palaeohabitats and climates was gleaned from
examination of fossil frog assemblages. Taphonomic biases are also
identified in this paper, and hypotheses relating to sampling and/or
ecological traits are proposed to explain such biases.
The third major paper (Paper 3) constitutes a significant site study of a
Kings Creek fossil deposit, site QML1396. It represents the first of my
broader excavations of the dated faunas, including the descriptions of over
40 taxa. This paper complements the results of the previous two papers by
presenting a palaeoenvironental interpretation based on the complete fauna
20
from a single fossil deposit. The stratigraphic and sedimentologic
investigative component documented the precise depositional setting of the
site. The taphonomic component of the study builds on the results of paper 2
above, and several biases were revealed in relation to both sampling by the
Pleistocene creek, and possible ecological factors. A palaeoecological
investigation of the deposit revealed significant information about late
Pleistocene Kings Creek habitats. Importantly, the paper provides the first
palaeoecological interpretations from this study that bear on megafaunal
extinction. The paper provides a baseline for comparison with deposits
discussed in subsequent chapters.
The fourth major paper (Paper 4) comprehensively investigates aspects of
stratigraphy, sedimentology and taphonomy of another major deposit in the
Kings Creek catchment, site QML796. Depositional environments are
precisely documented and potential taphonomic biases assessed. Climatic
indicators from the sediments are also discussed. It builds on the results of
paper 3 and allows sites QML796 and QML1396 to be litho- and
biostratigraphically correlated to each other. That is an important aspect of
the study as it allows future studies to examine species changes in the
catchment at different spatial scales. The investigation also allowed
additional development of hypotheses relating to Darling Downs megafaunal
extinction.
The fifth major paper (Paper 5) complements the QML796 site study of
paper 4, and provides a comprehensive interpretation of Pleistocene
palaeoenvironments, both at a single locality, and in a wider catchment
perspective (for additional aspects of fauna, see also Appendices 1 & 2:
Price, 2002 and Price & Hockull, 2005). It details the significant
documentation of late Pleistocene habitat change, ecosystem dynamics and
species extinctions on the Darling Downs. An extensive dating analysis
complements the palaeoenvironmental component and allows the site to be
correlated to independently derived records of Pleistocene climate change.
Hypotheses to explain late Pleistocene habitat and faunal changes support
those derived from investigations of papers 3 and 4. The results have
several important implications relating to the continental extinction of
Australian Pleistocene megafauna.
21
The final section provides an overarching discussion of the significance of
the findings, problems encountered, and future directions of the work.
The reference section includes all literary resources used in the thesis
including those in the published or submitted manuscripts. References used
specifically in the research papers accompany their respective manuscripts
for completeness.
The appendix section contains additional published manuscripts that
came from the work, but did not contribute to the main thrust of the thesis.
22
LITERATURE REVIEW
INTRODUCTION
There have been a growing number of scientific predictions of rapid and
catastrophic climate change occurring in the near future (Bengtsson et al.,
1996; Kappelle et al., 1999, Källen et al., 2001; Kershaw et al., 2003;
Phoenix & Lee, 2004). Significant numbers of such studies have indicated at
least a partial anthropogenic cause for climate change (Houghton et al.,
1996; Gordon et al., 2005; Root et al., 2005). Humans are directly altering
atmospheric composition through gas emissions and disrupting water
balance of large areas of the Earth’s surface through agriculture and other
land degradation activities, and thus, are affecting the cycling of carbon
through many of the planet’s ecosystems (Stern, 2002; Gordon et al., 2005).
Desire to predict possible future climate change has spawned an enormous
amount of literature (Bengtsson et al., 1996; Kappelle et al., 1999; Zachos et
al., 2001; Doorman & Woodin, 2002; Phoenix & Lee, 2004). Many studies
have focused not only on how to prevent or reduce the effects of predicted
climate change (Wigley, 1991; Kappelle et al., 1999; Scheffer et al., 2001),
but they also have attempted to produce predictive models of global warming
and its subsequent effects on biodiversity (Price & Rind, 1994; Zwiers &
Kharin, 1998; Boer et al., 2000; Rosenzweig, 2001; Western, 2001;
Callaghan et al., 2004; Phoenix & Lee, 2004; �ekercio�lu et al., 2004).
Biodiversity is increasingly used as a conceptual focus for the formulation
of conservation policies and practice, primarily in response to the strongest
themes underpinning the founding work on biological diversity: species
extinction and habitat loss. Our understanding of current threats to
biodiversity and the prospects for survival of extant species is informed by
palaeoecology, and in particular, knowledge of previous extinction events.
Mass extinction events have occurred throughout geological time. The Late
Ordovician, Late Devonian, terminal Permian, terminal Triassic and terminal
Cretaceous extinction events saw the loss of between 24-50% of all families
known at those times (Sharpton & Ward, 1990). Hypotheses developed to
explain such events suggest that the impact of extraterrestrial objects or
intense explosive volcanic activity may have adversely affected the climate of
23
those times, thus contributing to the catastrophic extinction rates (Sharpton &
Ward, 1990). However, one of the most important, but less understood
periods of species and habitat loss occurred more recently, during the
Pleistocene.
The emergence of modern floras and faunas on which humans depend for
food and shelter took place during the late Tertiary, finally being
accomplished by the late Quaternary. Most living terrestrial species evolved
at that time and many show adaptations to Quaternary environments.
Tertiary-Quaternary environmental changes on temporal scales on the order
of one hundred thousand years led to speciation within several groups. Many
species evolved fixed adaptations to specialised environments, while others
evolved more generalist adaptations that enabled them to inhabit broad
habitat niches (Lister, 2004). Environments that imposed strong selective
regimes were important in forcing adaptive changes in many species.
Subsequent migrational and evolutionary responses of taxa to fluctuating
Quaternary climatic cycles was a synergistic process (Lister, 2004). The
Quaternary was a time of evolution and subsequent extinction of some of the
largest land reptiles, birds and mammals that the world has ever known.
Colloquially known as the ‘megafauna’ (animals > 44 kg), those animals
included giant lizards, kangaroos and wombats in Australia, huge flightless
moas in New Zealand, and giant ground sloths, mammoths and mastodons
in the Americas. Hypotheses concerning the extinction of those spectacular
creatures during the late Quaternary have been the subject of contentious
and heated debate (e.g., Flannery, 1990 versus Wright et al., 1990; Flannery
1994, 1998 versus Benson & Redpath, 1997, 1998; Gillespie & David, 2001
and Roberts et al., 2001a, b, c, versus Field & Fullagar, 2001 and Wroe &
Field, 2001a, b; Grayson & Meltzer, 2003, 2004 versus Fiedel & Haynes,
2004; Burney & Flannery, 2005; 2006, versus Wroe et al., 2006). The recent
megafaunal extinction differs from all other known mass extinction events
because man has been suggested as the causative agent. Anthropogenic
factors have been clearly implicated in megafauna extinctions in some
regions (e.g., New Zealand; Worthy & Holdaway, 2002), but the role of man
remains unclear in regions such as the Americas and Australia. The paucity
24
of well-dated late Pleistocene megafaunal deposits makes it difficult to test
such extinction hypotheses.
Although Pleistocene deposits containing megafaunal remains are
common throughout Australia (Archer, 1984), few are as diverse and well
represented as those of the Darling Downs, southern Queensland. Over 50
megafauna-bearing deposits have been recorded in the region (Molnar &
Kurz, 1997), including some of the youngest deposits known in Australia
(Roberts et al., 2001a). Despite the significance of the deposits, little work
has been directed towards understanding palaeoecological aspects of the
region. Hence, the research presented here is aimed at better understanding
the Pleistocene faunas of the Darling Downs, their responses to
environmental changes, and their subsequent extinction.
Today, we are in an interglacial period and face similar climatic cycling
regimes to those patterns of climate change evidenced in the Pleistocene
geological record (Berger & Loutre, 2002). At this time of widespread
apprehension over human impacts, it is helpful to consider the history and
effects of past environment fluctuations (Burney & Flannery, 2005). To
understand life as we know it, it is essential to know its history; and to
conserve biodiversity into the future, it is essential to learn lessons from the
past. Knowledge of prehistoric biodiversity may provide insights into the
causes of extinction and the vulnerability of different types of species.
Importantly, such information may help highlight what the danger signs are,
i.e., aspects crucial for the development of strategies for conservation. It is
essential to know if the risks faced by species and ecosystems today are the
same as those faced by species in the past. Studies of Pleistocene climate
fluctuations and species extinction may have predictive value for assessing
the effect of climate change on extant species.
PLEISTOCENE
Relative to the past 65 million years of Tertiary geological history, the speed
and amplitude of global temperature oscillations during the Quaternary were
unprecedented (Zachos et al., 2001). The climate of the Quaternary was
dominated by repetitive glacial and interglacial cycles, i.e., ice ages. From
25
2.7 million years (Ma) to 800 thousand years ago (ka), such cycles were
dominated by 41 ka oscillations, and since 800 ka, by 100 ka oscillations
(Ashkenazy & Tziperman, 2004). Such transitions from glacial to interglacial
periods and variability were driven by orbital forcing (i.e., variations in the
Earth’s eccentricity, axial tilt, and precession; Milankovitch, 1941; Paillard,
2001). In the oceans, sea level fluctuated markedly, periodically encroaching
and retreating across coastal plains (Lambeck & Chappell, 2001).
Continental glaciers and ice sheets developed in the Northern Hemisphere
and contracted or expanded in response to the cyclicity of glacial and
interglacial periods (Hubberten et al., 2004). In regions of the Southern
Hemisphere where glaciers were not as significant (such as Australia;
Barrows et al., 2002), extensive arid zones developed in response to the
cool, dry and windy glacial periods (Bowler, 1986; Hesse et al., 2004).
Quaternary climate oscillations led to dramatic shifts in vegetation structure
in most regions of the world. Vegetation changed in structure and
composition as dictated by both climate and the differential response of
individual floral taxa to climate (Webb et al., 2003; Shuman et al., 2004). In
many regions, vegetation responded quickly (within ~100 years) when
climate changed rapidly on centennial scales (Webb et al., 2003). In the
Northern Hemisphere, changes from open steppe and herb tundra to open
shrub tundra were commonly associated with shifts towards cooler
conditions (Andreev et al., 2002, Lacourse et al., 2005). In the Southern
Hemisphere, interglacials were dominated by woodlands, whereas glacials
were dominated by open scrub and grasslands (Hope et al., 2004). Thus,
progressive changes toward more open conditions were more likely to occur
during glacial cycles.
Some of the most dramatic shifts in vegetation have been documented in
deposits generally younger than 50 ka, such as in Australia (Johnson et al.,
1999; Turney et al., 2001b; 2004; Field et al., 2002), Eurasia (Andreev et al.,
2002; Hubberten et al., 2004) and America (Webb et al., 2003; Shuman et
al., 2004). Those changes may have been responses to naturally driven
climatic variables such as increases in the severity and cycling of El Nino
Southern Oscillation (Turney et al., 2004). However, the precise effects of
naturally driven climate change as a causative agent of late Pleistocene
26
vegetation changes may be obscured by an additional confounding factor-
the global expansion of modern humans, Homo sapians.
MEGAFAUNAL EXTINCTION
Late Pleistocene climatic instability coincided with the global extinction of
almost 100 genera of large-sized terrestrial vertebrates (Barnosky et al.,
2004b). Such extinctions were most dramatic in the Americas and Australian
regions where 72-88% of all megafaunal taxa were lost (Barnosky et al.,
2004b). However, extinctions were moderate in Africa, Europe and Asia,
where only 18-36% of megafaunal genera became extinct (Barnosky et al.,
2004b). It is commonly suggested that the long history of human predation
on megafaunal species in such areas created selective pressures for prey
wariness and defensive behaviour (Fiedel & Haynes, 2004), and that may
explain the lower extinction rates. However, thus far there is no universally
accepted hypothesis to explain Pleistocene global megafaunal extinctions,
particularly in areas such as Australia and the Americas.
The debate over the causes of the extinctions have become particularly
polarised in recent years, with several hypotheses being suggested. The
most popular are those that suggest either: 1) an anthropogenic component
to the extinctions, via overhunting, or indirect habitat or ecosystem
modifications (Martin, 1984; Diamond, 1989b; Flannery, 1990; 1994; 1999a;
MacPhee & Marx, 1997; Miller et al., 1999; 2005a; Alroy, 2001, Brook &
Bowman, 2004; Diniz-Filho, 2004; Fiedel & Haynes, 2004; Johnson &
Prideaux, 2004; Lyons et al., 2004a; Prideaux, 2004, Wroe et al., 2004;
Burney & Flannery, 2005; Johnson, 2005a, b; Lowry, 2005; Steadman et al.,
2005; Surovell et al., 2005); 2) naturally driven climatic changes (Graham &
Lundelius, 1984; Guthrie, 1984, 2003; Ficcarelli et al., 1997; Grayson &
Meltzer, 2003; Kuzmin & Orlova, 2004; Shapiro et al., 2004; Stuart et al.,
2004), or 3) a combination of both (Calaby, 1976; Owen-Smith, 1987, 1988;
Murray, 1991; Frison, 1998; Field & Dodson, 1999; Forster, 2003; Barnosky
et al., 2004b; McNeil et al., 2005; Trueman et al., 2005; Wroe, 2005;
Boeskorov, 2006; Bulte et al., 2006).
27
Anthropogenic models of extinction
On islands such as New Zealand, humans have caused extinctions through
multiple synergistic effects involving overhunting and indirect habitat
modification (Anderson, 1989; Worthy & Holdaway, 2002). However,
megafaunal kill sites and other direct evidence of human induced habitat
modification has yet to be demonstrated on the continents where Pleistocene
extinctions were most dramatic, i.e., Australia and America (Flannery, 1990;
Grayson, 1991; 2001; Grayson & Meltzer, 2003). Hypotheses of
anthropogenic-induced megafaunal extinction include: 1) blitzkrieg (rapid
over-hunting); 2) sitzkrieg (fire, habitat alteration); and 3) hyperdisease
hypotheses.
Blitzkrieg
The global blitzkrieg hypothesis explains differential rates of megafaunal
extinctions between the world’s land masses during the late Quaternary
(Martin, 1963; 1984). The hypothesis centres around five main observations
(Wroe et al., 2004). 1) Megafaunal extinction rates were highest on
landmasses where humans colonised within the last 60 000 years (Roberts
et al., 2001; Fiedel & Haynes, 2004; Lyons et al., 2004a; Burney & Flannery,
2005; Surovell et al., 2005). 2) Species on remote islands (e.g., Polynesia,
West India) have proven to be vulnerable to human hunting (Worthy &
Holdaway, 2002; Steadman et al., 2002, 2005). 3) Ethnographic data
suggest that humans preferentially hunt large-sized species (Duncan et al.,
2002). 4) Late Quaternary extinctions were more significant in large-bodied
taxa than small-sized taxa (Johnson, 2002; Brook & Bowman, 2004;
Johnson & Prideaux, 2004). 5) Climatic fluctuations during the Quaternary,
prior to the last glacial maximum and human colonisation, did not result in
significant megafaunal extinction (Martin, 1984; Flannery, 1990; 1994;
Moriarty et al., 2000; Barnosky et al., 2004a; Lyons et al., 2004a). Blitzkrieg
extinction events are considered to have occurred if extinction takes less
than 500 years (Barnosky et al., 2004b), whereas more generalised overkill
is considered to have occurred in 1 500 years or more (Whittington & Dyke,
1984). The basic blitzkrieg hypothesis suggests that a combination of
selective hunting and prey naiveté produced significant extinctions wherever
28
humans colonised new land masses during the late Quaternary (Martin,
1984). A more attritional overkill hypothesis of megafuana extinction was
proposed for Australia by Prideaux (2004). Prideaux (2004) suggested that
megafauna attrition over a long duration (e.g., 20 000 years) was driven by
an elevation of human-based hunting pressures following initial human
colonisation. A combination of small population sizes and low reproduction
rates of megafaunal species may have rendered megafauna taxa
susceptible to increased predation pressures (Murray, 1991; Johnson, 2002;
2005b; Prideaux, 2004).
However, there is little direct evidence of human interaction with
megafaunal species. Sites documenting human butchery of megafaunal
species are particularly rare (Grayson & Meltzer, 2003; Wroe et al., 2004). Of
more than 70 late Quaternary archaeological sites in America, less than 20
document the human processing of megafaunal taxa (Grayson & Meltzer,
2002; Surovell et al., 2005). Additionally, those kill or butchery sites are
restricted only to large-sized proboscidians (i.e., mammoths and mastodons).
Demonstrable kill sites for other common late Quaternary megafaunal
species such as camels, horses and sloths are completely lacking in North
America (Grayson & Meltzer, 2003) and are rare in South America (Nami,
1996; Alberdi et al., 2001). Therefore, because the more common
megafauna are rarely associated with the butchery sites, those data are not
entirely consitent with blitzkrieg extinction (Grayson & Meltzer, 2003).
Similarly, few sites show evidence of an association between humans and
megafaunal species in Australia. Cuddie Springs, northern New South
Wales, shows a direct, in situ association between humans and megafaunal
species (Dodson et al., 1993; Field & Dodson, 1999; Trueman et al., 2005).
However, human processing marks recorded on fossil bone from the deposit
are related to an extant species of kangaroo, not extinct megafaunal taxa
(Field & Dodson, 1999). Rarity of kill sites in America and Australia has been
used as evidence to support the blitzkrieg extinction model (Martin, 1984;
Flannery, 1990). That is, because of the rapidity of a blitzkrieg-type
extinction, kill sites are unlikely to be found (Fiedel & Haynes, 2004).
However, such arguments render the hypothesis very difficult to test. Ideally,
29
direct evidence of flagrant prey overuse is essential to sustain the blitzkrieg
hypothesis (Prideaux, 2004).
In the Americas, the presence of big-game hunting tools (e.g., stone spear
points) in the fossil record is commonly cited as supporting overkill models of
extinction (Martin, 1984). Thus, if such technology is lacking in other areas, it
may lend support to non-overkill mechanisms of megafauna extinction (Wroe
et al., 2004). In Australia, stone spear points are not known until the mid-
Holocene (Flood, 1995). An absence of specialised hunting technologies
does not preclude the hunting of megafauna, but rather, suggests that
optimum prey size and hunting efficiency is reduced (Wroe et al., 2004).
However, most Australian megafauna species weighed less than 100 kg,
markedly smaller than their ‘big-game’ counterparts of the Americas (Murray,
1991). Ethnographic data suggests that in Australia, humans hunted animals
as large as red kangaroos (46 kg, mean sex weight; Strahan, 1995) and
crocodiles (327 kg, mean sex weight; Webb & Manolis, 1989) with
unsophisticated hunting tools such as clubs and wooden spears (Mulvaney &
Kamminga, 1999). Thus, anthropogenic predation on the majority of
Australian Pleistocene megafauna was possible by hunters with relatively
unsophisticated hunting technologies. Additionally, if big-game hunting tools
for taxa as large as Diprotodon (2 700 kg; Wroe et al., 2003a) ever existed, it
may be unlikely that such technologies would have been retained for tens of
millennia (i.e., into the Holocene) after they were last useful (Prideaux,
2004). In Australia, there is evidence of the manufacture of more efficient
stone tools from late Pleistocene to the Holocene. On a parallel, there is also
an increase in the efficiency of plant processing technology (e.g., seed
grinding) since the late Pleistocene (Fullager & Field, 1997). Without
specialised plant processing technology, societies were likely more
dependent on meat than advanced societies that could exploit a range of
plant resources (Wroe et al., 2004). An absence of specialised plant
processing technologies may have acted as a constraint on both human
population sizes, and their ability to disperse. However, the affect of plant
processing technology on Australian megafauna-human interaction is largely
unknown. For the American situation, Bulte et al. (2006) supported overkill
models, and suggested that the role of anthropogenic agriculture was
30
minimal in relation to megafauna extinction. Alternatively, they suggested
that humans attained high population densities by exploiting small-sized prey
taxa during and after megafaunal extinctions (Bulte et al., 2006). Small-sized
taxa may have been an important alternative food resource during and after
the period that megafaunal prey populations were extirpated.
Simulations developed to model overkill extinction hypotheses commonly
result in contradictions, favouring either rapid human-induced overkill (e.g.,
Alroy, 2001a, b; Diniz-Filho, 2004), rapid initial overkill followed by extinction
due to later stresses (Brook & Bowman, 2004), overkill with assistance from
climate (Bulte et al., 2006), natural climate changes (e.g., Choquenot &
Bowman, 1998), or they are inconclusive (e.g., Beck, 1996; Brook &
Bowman, 2002). One of the most comprehensive, but controversial, models
was the Alroy (2001a, b) simulation. Alroy (2001a, b) focused on the initial
entry of Clovis hunters into North America and correctly predicted the fate of
34 of 41 species. The mean time to extinction was 895 years, thus
supporting overkill, but not blitzkrieg senso stricto. However, the model failed
to account for the low number of kill sites in North America, and then over-
predicted the effect of hunting by not allowing prey to lose naiveté to humans
as their populations increased. As in most other simulations, assumptions of
complete prey naiveté generally result in models that support overkill (Brook
& Bowman, 2002). Despite the shortcomings of the Alroy (2001a, b)
simulation, the model has the potential to be further developed by
incorporating assumptions of geographic ranges, carrying capacity, and
human and prey dispersal (Barnosky et al., 2004b). However, in general, the
uncertain nature of human and megafauna interactions is a significant
impediment in developing realistic models of extinction. Additionally, most
computer simulations of human influences use data based on relatively
sophisticated modern day hunter-gathers as direct proxies for the behaviour
of Pleistocene societies. However, the assumption that Pleistocene human
behaviour is analogous to modern societies is undemonstrated and
therefore, limits the value of computer modelling (Wroe et al., 2006; Wroe et
al., in press). Another major assumption of algorithm-based models is that all
extinct taxa were present at the time of human arrival. However, in Australia
at least, chronologies demonstrating a temporal overlap between most
31
megafaunal taxa and humans are patchy at best. Although algorithm-based
models can integrate existing data to investigate various scenarios of
megafauna extinction, the output relies on many explicit and implicit
unconstrained assumptions.
Generally, the strength of the blitzkrieg and attritional predation
hypotheses are limited by a lack of reliable chronologies of initial human
colonisation and megafaunal extinction. The geographic distributions of
humans and other megafauna through time are very poorly constrained.
Overkill hypotheses rely on specific, but unproven chronologies of human
occupation and megafaunal extinctions. Thus, testing overkill hypotheses
requires more examples of megafauna co-occurring with humans in well-
stratified, unambiguously dated sites across the continents (Horton, 1984;
Prideaux, 2004). Head (1995) noted that unambiguously dated sites
containing evidence of human occupation that are too old, or megafauna that
are too young, “can blow it (some anthropogenic extinction hypotheses)
apart”. In Australia, recent chronologies and geochemical analyses reported
for the Cuddie Springs archaeological deposit (northern New South Wales),
have demonstrated a temporal overlap of humans and megafauna on the
Australian continent for a minimum of 15 000 years (Trueman et al., 2005).
Thus, the long temporal overlap between humans and megafauna
automatically refutes blitzkrieg, but not attritional, overkill extinction
hypotheses for Australian megafauna. Additional details regarding the
Cuddie Springs deposit are discussed below.
Sitzkrieg
Unequivocal impacts of human-induced habitat change on islands, such as
Madagascar, New Zealand, and Hawaii, have been cited as a potent
argument that prehistoric humans also caused extinctions on the continents
(Diamond, 1989a). Such island extinctions commonly occurred rapidly after
human arrival (James et al., 1986; Flannery, 1994; Steadman et al., 1999;
Burney et al., 2003; 2004). Initial human colonisation on islands such as New
Zealand was followed by massive environmental change. Those
environmental changes were the result of a combination of factors that
included the introduction of rats and dogs, fire-driven deforestation, and
32
vertebrate extinction. It is well documented and accepted that direct over-
hunting caused the extinction of the moa in New Zealand (Anderson, 1989;
Diamond, 1989a; Worthy & Holdaway, 2002). However, several smaller-
sized species were also lost due to subsequent habitat destruction, or
through direct predation or competition effects from taxa that arrived with
humans (Diamond, 1989b). Colloquially, such indirect anthropogenically-
related extinction events are known as ‘sitzkrieg’ extinctions (Diamond,
1989b; Barnosky et al., 2004b).
Island species are particularly vulnerable to sitzkrieg extinction events due
to the high level of endemism of their faunas. Island species may have small
population sizes and be confined to well-delineated areas of land that may
undergo rapid environmental change (Grayson, 2001; Grayson & Meltzer,
2002). Additionally, taxa that occur on islands that lack mammalian predators
commonly lose predator escape responses (Roff, 1994; Duncan &
Blackburn, 2004), and that may make them susceptible to extinction
following mammalian colonisation. However, the impact of sitzkrieg-related
factors on faunas of the continents is questionable, primarily because of the
greater range of refuges in such large landmasses. However, Fiedel and
Haynes (2004) recognised continents simply as gigantic islands and
suggested that while endemic taxa could escape anthropogenic related
pressures for a period of time, they could not escape indefinitely.
In Australia, the introduction of the dingo (Canis lupus dingo) by humans
3.5 ka (Gollan, 1984) has been implicated in the mainland extinction of the
thylacine (Thylacinus cynocephalus), Tasmanian devil (Sarcophilus harrisii),
and Tasmanian native hen (Gallinula morterii) (Johnson & Wroe, 2003).
Over-competition between the dingo with the thylacine and devil (Archer,
1974; Corbett, 1995) and over-predation of the native hen possibly led to
mainland extinctions of those taxa. However, the only clear evidence linking
the disappearance of those mainland species is the timing of the arrival of
the dingo. Other factors such as increases in the human population,
innovations in hunting technologies and more intensive use of resources,
and mid-Holocene climate changes may also have been contributing factors
to their extinction (Johnson & Wroe, 2003). With regards to Australian
Pleistocene megafauna extinctions, it is unknown if humans actively
33
introduced previously non-native species. Although several small-sized, non-
volant taxa entered Australia throughout the Pleistocene via natural
landbridges (Flannery, 1995; Winter, 1997), such species were unlikely to
have been introduced by humans.
On continental scales, the use of fire in the landscape by early human
colonisers has become a complex and contentious issue. Very few studies
have linked archaeological and palaeoecological data to determine the role
of anthropogenic fire in the landscape (Bowman, 1998). In Australia, the
function and role of aboriginal burning of modern landscapes has been well
documented (Jones, 1969; Nicholson, 1981; Kohen, 1995; Bowman, 1998;
Gott, 2005). The ‘fire-stick farming’ model developed to explain late
Pleistocene extinctions (Jones, 1969) suggests that early Aborigines
changed the frequency and nature of fires in order to manipulate animal and
plant resources. The effect of increased firing was to produce great changes
in the vegetation, essentially simplifying vegetation communities downwards
along the spectrum from mature forest to immature grassland (Horton, 1982;
Lowry, 2005). Long-term effects of fire include the reduction of dense
woodland forests and the expansion of savannah grasslands. Aboriginal
burning was probably important for developing and maintaining habitat
mosaics that favoured small-sized species (Johnston et al., 1989; Flannery,
1990; 1994; Bowman, 1998), and was probably detrimental for the survival of
megafaunal taxa, the majority of which depended on woodlands (Horton,
1980; 1982). Thus far, fire-related extinction has only been specifically
suggested for one species of Australian megafauna, the giant dromornithid
bird Genyornis newtoni, in central Australia (Miller et al., 1999; 2005a). Miller
et al. (1999; 2005a) investigated diets of Genyornis and extant emus,
Dromaius novaehollandiae, in the Lake Eyre region over the last 140 000
years. Miller et al. (1999; 2005a) suggested that dietary changes in Dromaius
and localised extinction of Genyornis at ~50-45 ka was the result of massive
habitat changes. They argued that climatic forcing of habitat changes at ~50-
45 ka was unlikely because the previous climatic shifts associated with the
penultimate glacial maximum (i.e., ~140 ka) did not result in such massive
ecosystem reorganisation (Miller et al., 2005a). Thus, Miller et al. (1999;
2005a) suggested that a changed fire regime driven by initial human
34
colonisers prompted the habitat changes, and ultimately, resulted in
Genyornis extinction. Genyornis was a specialised feeder and was unable to
adapt to the changing environment, whilst Dromaius had more generalised
feeding strategies and was able to survive the extinction event (Miller et al.,
2005a). However, evidence linking anthropogenic burning and Genyornis
extinction is ambiguous (Bowman, 2002; Wroe et al., 2004; Johnson,
2005a). Although chronologies presented by Miller et al. (1999; 2005a) may
correspond to initial human colonisation of the Australian continent, there is
no evidence of human occupation in the Lake Eyre region at ~50-45 ka.
Additionally, a paucity of charcoal in the fossil deposits does not support
significant firing of the landscape, either natural or anthropogenic.
Alternatively, a growing body of evidence is beginning to demonstrate that
shifts towards glacial biomes and major climatic instability occurred Australia-
wide around 50 ka (Bowler et al., 2003; Barnosky et al., 2004b; Hope et al.,
2004), and that may be associated with habitat change and species
extinction in the Lake Eyre region at that time.
More broadly, Johnson et al. (1999) and Miller et al. (2005b) suggested
burning and disruption of vegetation cover as a cause for modification of the
Australian Summer Monsoon (ASM) during the late Pleistocene. The
penetration of the ASM into the interior of the continent is dependent on the
transfer of moisture from the biosphere to the atmosphere. Thus, changes to
the vegetation type brought on by anthropogenic burning possibly reduced
the wet season feedback and diminished the effectiveness of the summer
monsoon (Johnson et al., 1999). Such a change may be implicated in the
extinction of the Australian megafauna. However, the role of humans in ASM
modification has been strongly contested (Horton, 2000; Bowman, 2002).
There are several gaps in the knowledge of the origins of the ASM, and that
lack of knowledge is associated with difficulties in differentiating potential
anthropogenic impacts from natural inherent variability (Bowman, 2002).
In the Australasian region, abrupt changes of charcoal concentrations in
late Quaternary pollen cores, such as those at Lake George (Singh &
Geissler, 1985), Lynch’s Crater (Kershaw, 1986; Turney et al., 2001b),
Lombok Ridge (Wang et al., 1998), Lake Eyre and Lake Frome (Luly, 2001),
indicate sudden increases in the incidence of fires. Such increases in fire
35
regimes commonly have been attributed to the role of human fire use in the
landscape (Bowman, 1998; Wang et al., 1998; Luly, 2001, Turney et al.,
2001). However, the relationship between increases in burning and
anthropogenic factors has been questioned, primarily because there is no
other direct evidence of humans in the landscape at those times (see Clark,
1983; Wright, 1986; Head, 1989; Bowman, 2002). Instead, the relationship
between humans and increases of charcoal concentrations has been linked
merely on the basis of dated chronologies between the age of the deposits
and supposed human colonisation (Bowman, 1998; 2002). Development of
accurate chronologies of initial human colonisation is extremely problematic,
and is discussed further below.
Hyperdisease
The hyperdisease hypothesis attributes Pleistocene megafaunal extinctions
to virulent diseases inadvertently brought in by newly arrived humans or
species that accompanied them (e.g., dogs; MacPhee & Marx, 1997; Fiedel,
2005). Smaller-sized taxa may have greater resilience to disease than large-
sized taxa as they have differing life history traits (e.g. shorter gestation time,
greater population sizes, etc.). Hence, Pleistocene disease-related extinction
events would have been biased towards larger-sized species (MacPhee &
Marx, 1997; Fiedel, 2005). For a disease to have the potential to result in
significant extinctions, several criteria must be met: 1) the pathogen must
have a stable carrier in a reservoir species; 2) the pathogen must have a
high infection rate; 3) the pathogen must cause a high mortality rate (circa
50-75%); and 4) the pathogen must have multiple hosts without causing a
threat to humans (Lyons et al., 2004b). With the exception of rabies, few
known viruses may fit such criteria (Lyons et al., 2004b). Even so, rabies has
a low incidence of infection (MacPhee & Marx, 1997).
Lyons et al. (2004b) attempted to model the affect of the West Nile virus
(recently introduced to North America) on bird species of different sizes and
taxonomic orders, and compared that to observed variables of Pleistocene
extinctions. They also demonstrated that it is more likely that hyperdisease
would target species of all sizes, a prediction in contradiction with the
observed patterns of Pleistocene extinctions (Lyons et al., 2004b). Hence,
36
even if a disease does meet all of the criteria of a hyperdisease (i.e., Lyons
et al., 2004b) it may not result in size-biased global extinction events such as
those of the late Pleistocene (Miller et al., 2005a).
Climate models of extinction
One of the major factors that has lent support to the overkill model of
extinction is that glacial-interglacial cycles have been operating for much of
the Pleistocene, yet most extinctions seem to be clustered near the time of
the latest Pleistocene glacial maximum, which is more or less coincident with
the introduction of humans in some areas (e.g., North America, Grayson &
Meltzer, 2002; Australia, O’Connell & Allen, 2004). However, in several
regions, particularly Australia, long-term records from coastal lakes and
pollen cores suggest that although aridification was an ongoing process
through the late Pleistocene, different glacial maxima were associated with
different degrees of aridity (Longmore & Heijnis, 1999; Hope et al., 2004,
Stevenson & Hope, 2005). Significantly, the last glacial maximum was the
most severe of those recorded and was followed by very dry conditions in the
Holocene (Nanson et al., 1992; Longmore & Heijnis, 1999; Lambeck et al.,
2002; Hope et al., 2004). If those results are correct, it provides a rational
explanation for why extinctions might be concentrated around the last glacial
maximum. The last glacial maximum may have been uniquely severe in
terms of aridity. The arrival of humans may be coincidental, but there is no
longer a requirement for an external (i.e., human) agency in the extinctions.
A major difficulty in postulating climatic change as the causal agent of
megafauna extinction has been determining exactly what effect such a
change would have had on individual faunas. Late Pleistocene climatically
driven vegetation changes occurred globally (Whitehead, 1981; Leyden,
1984; Barnosky, 1985; Jackson & Weng, 1999; Longmore & Heijnis, 1999;
Dupont et al., 2000; Andreev et al., 2002; Field et al., 2002; Webb et al.,
2003; Hope et al., 2004; Hubberten et al., 2004), but the direct effect on
particular faunas remains unclear (Johnson & Prideaux, 2004). In many
regions, the relationship between megafaunal extinction and vegetation
change is unclear because of a lack of reliable dates (Barnosky et al.,
37
2004b). Two main climatically related extinction hypotheses have been
proposed, the co-evolutionary disequilibrium, and mosaic nutrient models.
Co-evolutionary disequilibrium model
Coevolution refers to the common evolution of multiple taxa that share close
ecological relationships, with selective forces making evolution of a particular
taxon at least partially dependent on another (Graham & Lundelius, 1984). In
coevolved communities, a balance is established for the biota involved in the
interaction. Environmental change, such as that observed in late Pleistocene
communities, may cause dramatic biotic reorganisation resulting in
disequilibrium. The consequences of coevoutionary disequilibrium may vary
from the establishment of a new equilibrium or to the extinction of one or
more of the species involved. Late Pleistocene environmental effects may
have disrupted coevolutionary equilibrium, and thus reduced niche
differentiation of megaherbivores and increased competition between
species. Coevolutionary disequlibrium is not restricted to particular
taxonomic groups, size or ecological categories, and has been used to
explain the differential extinction or survival of herbivores during the
Pleistocene (Graham & Lundelius, 1984).
Two competing models for how communities might react to such
environmental changes were developed by Clements (1904; 1916) and
Gleason (1926). The Clementsian model suggests that large groups of
species in equilibrium are determined by biological interactions (primarily
competition) and move dependently as integrated communities (Clements,
1916). The Gleasonian model suggests that species respond to
environmental change individualistically, in accordance with individual
tolerance limits (Gleason, 1926). Therefore, communities are continually
emergent features (Graham et al., 1996; Cannon, 2004). Hence, non-
analogue assemblages (i.e., fossil assemblages of modern taxa whose
extant populations are allopatric; Lundelius, 1983; 1989) may be formed by
species responding in a Gleasonian manner to environmental changes.
Graham et al. (1996) conclusively demonstrated that, for North American
mammals at least, species do respond individualistically to environmental
changes (i.e., in a Gleasonian manner), although other factors including
38
biological interactions and stochastic events may also play a role.
Gleasonian-type responses may drive evolutionary change at sub-
continental spatial and temporal scales, with Clementsian-type responses
operating at smaller temporal and geographic scales (Barnosky, 2001).
Mosaic-nutrient model
The mosaic-nutrient model of late Pleistocene extinction events suggests
that climatic changes in seasonal regimes decreased plant diversity and
spatially increased zonation. Such changes resulted in: 1) a shorter, less
diverse growing season; 2) decreases in the quality and quantity of
resources; and 3) development of more homogeneous habitats (Lundelius,
1983, 1989; Guthrie, 1984; Stafford et al., 1999). Those changes were likely
to have resulted in decreasing community diversity, range contractions,
lowering of body masses, and commonly, extinction (Guthrie, 1984).
The mosaic-nutrient extinction hypothesis is difficult to test in several
regions. In areas such as Australia, the late Pleistocene fossil record of
large-sized taxa is poorly known, and their chronologies are poor owing to a
lack of reliable dates. Hence, the precise geographic ranges of megafaunal
taxa during the Pleistocene are poorly known. In North America, the fossil
record is better documented. The average distances of late Pleistocene
geographic range shifts of mammal species were on the order of 1 200 - 1
400 km, and they appear to have been similar during the pre-glacial to
glacial, glacial to Holocene and Holocene to recent intervals (Lyons, 2003).
Such periods were characterised by climatically driven vegetational changes
(Webb et al., 2003) and coincided with increased seasonality. Hence, the
mosaic-nutrient extinction hypothesis may at least partially explain late
Pleistocene megafaunal extinction in North America.
Factors relating to the lowering of body masses of late Pleistocene taxa
are also difficult to assess. Relict late Pleistocene populations that
experienced decreasing body mass (i.e., dwarfing) were common amongst
many island biotas throughout the world, including the islands of southeast
Asia (rhinocerotids, proboscidians, hominins; Anderson, 1984; Brown et al.,
2004; Morwood, et al., 2004; Diamond, 2004), New Guinea (macropods &
diprotodontids; Flannery, 1999b), and the Mediterranean (mastodonts,
39
hippopotamids; Martin, 1984). Endemic island mammalian faunas originated
by the arrival of mainland species swimming or rafting, or by movement over
landbridges that were open for short periods of time. Isolated islands would
have provided short-term habitats for species concentrations (King &
Saunders, 1984). Dwarfed lineages show a marked decrease in size in
comparison to their mainland precursors, reflecting incipient dwarfing in
response to their insular distributions (Lister, 2004). Dwarfing has also been
documented in several continental mammal populations (Marshall &
Currucini, 1978; Forsten, 1991; Guthrie, 2003). Dwarfing on larger
landmasses may have been an evolutionary response to a decline in nutrient
quality of plant food, and hence, may have been an appropriate response to
the increasing unpredictability in the length of growing seasons (Marshall &
Currucini, 1978). Larger-sized species exhibited the largest-size reduction.
Hence, dwarfing was related to body size and was an adaptive process that
may have resulted from density dependent factors (i.e., resource-limited
systems). However, pressure from human hunting may also be responsible
for selecting larger-sized individuals (Davis, 1981; McDonald, 1984;
Flannery, 1990). Human-induced processes may result in a shift for the
selection of early maturing dwarfs, thus providing a genetic basis for the shift.
However, dwarfing may be a process that is not open to all species. For
example, some large specialised browsing species can only maintain their
niches because their bodies are an essential physical and physiological
adjunct to their feeding adaptation (Murray, 1991). Grazing species may be
able to scale-down without shifting their adaptive zone (Murray, 1991).
Regardless of the causes of dwarfism, no hypothesis directly explains why
some continental lineages tended towards dwarfism and others did not.
Additionally, most interpretations that dwarfing took place are drawn on the
basis of endpoints only, with only a few rare cases where continuous body
size reduction over time was observed (e.g., Guthrie, 2003). The exact cause
of dwarfed lineages of species on continents is unclear, but such dwarfing
may be the result of resource-limited systems, human predation pressures,
or a combination of both.
40
Multicausal or ecological models of extinction
Disagreement over a single cause of megafaunal extinction has led to the
development of hypotheses invoking a muliticausal or ecological explanation
(Calaby, 1976; Murray, 1991; Field & Dodson, 1999; Barnosky et al., 2004b;
Wroe, 2005). Emerging evidence suggests that humans contributed to the
extinctions in some areas, but were not solely responsible for extinctions
everywhere (Barnosky et al., 2004b). The intersection of human populations
and impacts of pronounced climate change possibly drove the geography
and timing of megafaunal extinctions in the Northern Hemisphere (Gonzalez,
2000; Barnosky et al., 2004b; McNeil et al., 2005; Boeskorov, 2006).
Mulitcausal models of extinction have also been suggested for Australia
(Field & Dodson, 1999; Barnosky et al., 2004b; Trueman et al., 2005).
However, like other hypotheses regarding megafaunal extinction, they are
limited by imprecise chronologies (Field & Dodson, 1999; Barnosky et al.,
2004b). Specific mulitcausal or ecological models include the keystone
herbivore hypothesis, and self-organised instability model.
Keystone herbivore model
The keystone megafauna extinction hypothesis links an assumption of both
overkill and climate hypotheses, principally, that there are strong interactions
between animal grazing and ecosystem processes (Owen-Smith, 1987;
1988; Zimov et al., 1995). Mammals, particularly large-sized taxa, can act as
keystone species to influence ecosystem dynamics (Sinclair, 2003; Haynes,
2006). The keystone herbivore Pleistocene extinction model was originally
based on the ecology of extant browsing and grazing megaherbivores (i.e.,
terrestrial herbivores >1000 kg; Owen-Smith, 1988), such as elephants
(Loxodonta africana) and white rhinoceros (and Ceratotherium simum) in
Africa. Megaherbivores, particularly adults, are immune to non-human
predation effects. Thus, those species may attain high population densities
such that they can radically transform vegetation structure and maintain
vegetative mosaics (Owen-Smith, 1987; 1988; Sinclair, 2003). For example,
extant elephant populations in Africa can change closed woodlands or
thickets to grassy savannah (Owen-Smith, 1987; 1988; Haynes, 2006).
41
Grazing white rhinoceros can transform tall grasslands into more nutritious
short grasslands (Owen-Smith, 1987; 1988). Thus, selective removal of
Pleistocene megaherbivores, either through synergistic effects such as
climate change or overhunting, may have promoted reverse changes to plant
communities. Such habitat changes may have produced dramatic cascading
effects on smaller-sized species. The conversion of heterogeneous
woodlands and grasslands to homogeneous forest and prairie grasslands in
North America during the late Pleistocene may be a consequence of the
removal of megaherbivores (Owen-Smith, 1987; 1988). Zimov et al. (1995)
suggested that the removal of keystone species through over-hunting in the
late Pleistocene Beringia resulted in the conversion of a vegetation mosaic
with abundant grass-dominated steppe to a mosaic dominated by moss
tundra. Removal of megaherbivores in Australia may have triggered an
expansion of shrublands and scrub, and led to the contraction of
heterogeneous woodlands and grasslands (Johnson, 2005a). However,
since many continental Pleistocene glacial maxima were characterised by an
increase in the homogeneity of habitats (e.g., Hope et al., 2004),
differentiating between natural climatically-driven versus anthropogenically-
driven vegetation changes in the last glacial maximum is difficult.
A major issue relating to the validity of the keystone species extinction
model is the timing of when megaherbivores went extinct in relation to
smaller-sized taxa. The basic prediction of the model is that keystone taxa,
such as proboscidians, should be the first to disappear in the fossil record
(Barnosky et al., 2004b), as observed for South American representatives
(Ficcarelli et al., 1997). However, in Eurasia, Alaska and central North
America, proboscidians were among the last taxa to become extinct
(Vasil’ev, 2001; Stuart et al., 2002; 2004; MacPhee et al., 2002; Guthrie,
2003; 2004; Fiedel & Haynes, 2004; Kuzman & Orlova, 2004). In Australia,
only two genera of megaherbivores were present during the late Pleistocene,
Diprotodon and Zygomaturus. Extinction chronologies for Australia are much
less secure than those for the Americas and Eurasia. However, current data
suggest that those genera also were among the last to disappear (Field &
Dodson, 1999; Roberts et al., 2001a). Hence, the keystone herbivore
extinction model is not supported for Australia. Regardless, the sudden
42
removal of megaherbivores would presumably have had dramatic effects on
late Pleistocene plant communities (Owen-Smith, 1987, Haynes, 2006).
Self-Organised Instability
An additional ecological-based megafauna extinction hypothesis that has
received little attention thus far, is the self-organised instability (SOI)
hypothesis proposed for Australia by Forster (2003). The SOI megafauna
extinction hypothesis was developed following recent advancements in the
study of ecosystem complexity (e.g., Bak, 1996; Solé et al., 2002). Forster
(2003) suggested that immigration of fauna from southeast Asia coupled with
the speciation of existing taxa in response to increasing aridity since the late
Pliocene (Gallagher et al., 2003) led to a level of self-organised instability of
Australian Pleistocene faunal assemblages. Increases in the immigration of
humans during the late Pleistocene also may have increased the connectivity
of other faunal elements into Australia. The combined effect was to make
megafauna inherently susceptible to extinction. However, the hypothesis has
yet to be tested. Several species entered Australia via northern landbridges
during the late Tertiary and Quaternary. ‘Old endemic’ rodents arrived 7-5
Ma (Watts & Aslin, 1981; Godthelp, 1990). ‘New endemic’ rodents and other
small, non-volant mammals entered Australia via xeric corridors throughout
the Pleistocene (Taylor & Horner, 1973; Godthelp, 1990; Flannery, 1995),
although most arrivals appear to be Holocene events (Winter, 1997).
However, the rate, timing, and effect on endemic fauna resulting from such
Plio-Holocene immigrations are unknown. Several taxa also entered North
America during the Tertiary-Quaternary. The extinct Harlon’s ground sloth
(Paramylodon harlani), and mammoths (Mammuthus spp.) arose from South
America and Eurasia respectively, and commonly occurred sympatrically in
the Pleistocene North America (McDonald & Pelikan, 2006). Although both
taxa occurred in a similar habitat and filled a similar niche, minor differences
in their ecologies allowed them to avoid competition, thus enriching the North
American Pleistocene mammalian fauna. Moreover, there is no evidence
that their appearance in North America resulted in the extinction of any
native species (McDonald & Pelikan, 2006). Generally, at least for Australia,
the SOI megafauna extinction hypothesis is still in its infancy and is difficult
43
to test with the current paucity of data on rates of faunal immigration and
speciation during the Pleistocene (Forster, 2003).
Chronologies
Critical to the understanding of the causes of megafaunal extinction is the
development of accurate chronologies of human colonisation and species
extinctions. Even in areas, such as the Americas, where chronologies of
human arrival and megafauna extinction appear to be relatively well
established, controversy concerning the causes of extinction remains
(Barnosky et al., 2004b). One of the main issues concerning the timing of
human arrival and megafaunal extinctions in regions such as Australia, is
that such events may have occurred just outside the practical limits of
radiocarbon dating. Several dates of human arrival have been suggested,
ranging from >100 ka (Wang et al., 1998), >60 ka (Roberts & Jones, 1994;
Thorne et al., 1999), and 50-42 ka (Fifield et al., 2001; Gillespie, 2002;
Bowler et al., 2003), with most of those dates obtained from optically
stimulated luminescence (OSL), electron spin resonance (ESR), U-series
dating, or radiocarbon dating techniques. A recent review suggested that
humans had colonised the continent by 45-42 ka, and that older dates are
not well supported (O’Connell & Allen, 2004).
Until recently, specific chronologies of Australian megafauna extinctions
were lacking. Baynes (1999) reviewed almost 100 radiocarbon dates that
were associated with Australian megafauna remains, but rejected most dates
as being unreliable, including all dates younger than 28 ka. A major problem
for the accurate dating of Australian megafauna deposits is that most known
deposits are beyond the practical limit of the radiocarbon dating technique
(Gillespie, 2002). Therefore, Roberts et al. (2001a) developed chronologies
for megafauna using OSL and U/Th dating methods and suggested that the
last Australian megafauna occurred at ~46.4 ka. However, their sampling
procedures and subsequent interpretations have been strongly criticised
(Field & Fullager 2001; Wroe et al., 2004). Aside from the fact that the 46.4
ka date falls near the limit of effective radiocarbon dating (Gillespie, 2002),
Roberts et al. (2001) analysed only deposits that contain articulated remains
of megafauna. Although the sampling strategy was aimed at limiting the
44
possibility of reworking of older megafaunal remains into younger deposits, it
automatically excludes the majority of known late Pleistocene megafauna
sites, including, for example, most archaeological sites (e.g., Field &
Fullagar, 2001). Many such sites have been dated younger than 46.4 ka,
including Cuddie Springs, where rigorous geochemical assessment
suggested minimal reworking of fossil material (Trueman et al., 2005). The
stratigraphic integrity and provenance of fossils from younger deposits may
be questioned (Baynes, 1999), but reworking cannot be assessed on the
basis of dating alone (Field & Fullagar, 2001; Trueman et al., 2005). Specific
hypotheses of reworking can be tested by using data from disciplines, such
as taphonomy, sedimentology, geochemistry, archaeology and
geomorphology, to independently establish the context and accumulation
processes of a fossil deposit (e.g., Behrensmeyer, 1988; Lyman 1994;
Trueman et al., 2005).
Roberts et al. (2001a) dated 28 deposits from several widely spaced
geographic regions, but dismissed the results of 19 of those sites because
they either lacked articulated skeletons or to reduce bias for statistical
analysis. Hence, the effective sample size used to predict the timing of the
extinction event was only nine ‘securely’ dated sites. Perhaps more
importantly, stratigraphic, sedimentologic, taphonomic, and palaeoecologic
aspects of the majority of those nine sites remain unpublished. Hence, the
stratigraphic provenance of fossil material and dating results from those sites
cannot be independently assessed. Regardless, the two youngest deposits
were from southwestern Western Australia (Kudjal Yalgah Cave, 46 ± 2 ka)
and southeastern Queensland (Ned’s Gully, 47 ± 4). Roberts et al. (2001a)
subsequently concluded that megafauna went extinct synchronously.
However, of 25 Pleistocene megafaunal genera, 20 survived in temperate
Australia until at least 80 ka, and only six megafaunal genera were present
until at least 46 ka (Roberts et al., 2001a). Thus, on the basis of those data,
the extinction of the Australian Pleistocene megafauna appears to have been
progressive, not an immediate or synchronous event as suggested by
Roberts et al. (2001a). Additionally, assuming decreasing diversity in
megafauna communities from >80 ka - 80 ka, and 80 ka - 46 ka, and thus,
potentially predating human arrival, a significant role is posited for non-
45
anthropogenic mechanisms, such as climate, in driving megafauna
extinction. A combination of climate deterioration and human arrival post-50
ka may have compounded on an extinction ‘event’ already underway. That
interpretation may be supported by evidence from the Cuddie Springs
archaeological deposit (Field & Dodson, 1999; Trueman et al., 2005). A
combination of geochemical analyses and radiocarbon dating indicated that
at that site, megafauna extinction was attritional, with megafauna suffering
extinction behind a backdrop of climatic deterioration ~30 ka (Field and
Dodson, 1999; Trueman et al., 2005).
Despite the lack of agreement on the precise timing of late Pleistocene
human colonisation and megafaunal extinction, several hypotheses have
been developed for anthropogenic or climatic models of Australian
megafauna extinction. Many of those hypotheses rely on, or can be tested
with, the chronologies presented by Roberts et al. (2001a).
For example, Johnson and Prideaux (2004) suggested that megafauna
extinction was not related to their feeding ecology, i.e., browsers or grazers.
Rather, extinction was related to body size, a hypothesis echoed by Brook
and Bowman (2004). That interpretation is in contrast to Miller et al. (1999;
2005a) who argued that dietary specialisation of megafauna was a causative
factor in their extinction. Regardless, the Johnson and Prideaux (2004)
hypothesis is not supported unless all Australian Pleistocene megafauna
went extinct synchronously. Thus, Johnson and Prideaux (2004) followed
Roberts et al. (2001a) and assumed that all browsing and grazing
Pleistocene taxa suffered synchronous extinction ~46 ka. However, there are
very limited, or absent, chronologies for several species and even for some
of the genera that Johnson and Prideaux (2004) discussed in particular. For
example, there is little or no systematic evidence that some taxa (e.g.,
Phascolomys spp., Ramsayia spp., Kolopsis watutense., Macropus
piltonensis) even survived until the late Pleistocene (Roberts et al., 2001a).
Additionally, there appears to be a high degree of confusion in the literature
regarding the ecological characteristics of extinct megafaunal species,
principally, in body weight and dietary estimates (see also Johnson and
Prideaux, 2004). Subjectively determined body weight estimates that were
taken from the literature (e.g., Long et al., 2002) and utilised by Johnson and
46
Prideaux (2004), contrast significantly with other body weight estimates that
were derived using other deterministic methods (e.g., femoral circumference
or endocranial volume analyses) (e.g., Murray, 1991, Wroe et al., 1999;
2003a, b; Smith et al., 2003). In some cases, such estimates vary in the
range of almost 200% (e.g., Diprotodon optatum 1150 kg – 2786 kg).
Similarly, interpretations of megafauna diets derived from the literature and
utilised by Johnson and Prideaux (2004) appear to vary significantly. For
example, Johnson and Prideaux (2004) assigned Protemnodon anak, P.
brehus, and P. roecheus as browsers, whereas other interpretations
suggested that those Protemnodon congenors were grazers (Bartholomai,
1973a) or mixed feeders (Murray, 1984). Body mass and diet are among the
most critical aspects of an organism’s ecology, and therefore, palaeoecology
relies on accurate estimates of those fundamental aspects (Alexander, 1998;
Witt & Ayliffe, 2001). Generally, body weight and dietary estimates of many
Australian megafaunal groups are badly in need of revision.
Lyons et al. (2004a) observed that megafauna extinctions in Australia and
on other continents occurred rapidly following initial human colonisation, and
posited a major role for human hunting in forcing the extinctions. However,
as with Johnson and Prideaux (2004), Lyons et al. (2004a) assumed that all
Australian megafauna taxa suffered extinction at 46 ka. However, Lyons et
al. (2004a) appears to have inadvertently overlooked evidence from the
Cuddie Springs archaeological deposits that indicates a human-megafauna
continental overlap of 15 ka (Field & Dodson, 1999; Trueman et al., 2005).
Lyons et al. (2004a) also suggested that there was no evidence of climate
change around 46 ka, and thus, that provided additional support for an
anthropogenic component to megafauna extinction. However, several
references utilised by Lyons et al. (2001a) that suggested an absence of
climate change at the time of megafaunal extinction are outdated (e.g.,
Kershaw, 1974; 1978; 1986; 1994). More recent advancements in dating and
other palaeoecological analytical techniques have established fluctuating
climatic trends towards aridity coupled with dramatic vegetational
disturbances from 50 ka (Longmore & Heijnis, 1999; Johnson et al., 1999;
Turney et al., 2001b; 2004; Bowler et al., 2003; Hope et al., 2004).
47
Horton (1984; 2000) suggested that late Pleistocene aridity expanded
from the centre of Australia outwards, and fragmented and compressed
megafauna habitats to the margins of the continent. Megafauna populations
were restricted to those isolated pockets of habitat and were unable to
migrate due to resource tethering effects. Finally, over-competition between
individuals in those restricted habitats led to local extinctions of megafaunal
populations (Horton, 1984; 2000). Such events may have been repetitive in
different regions, eventually leading to the extinction of a species.
Essentially, the hypothesis suggests that megafauna extinction was
asynchronous, and occurred in specific geographic patterns, primarily, from
the arid centre outwards over thousands of years during the approach of the
last glacial maximum (Horton, 1984; 2000). Hence, the hypothesis does not
require an anthropogenic role in the extinctions. Testing that hypothesis is
difficult considering the lack of accurate chronologies for many megafaunal
taxa. However, chronologies for the giant bird, Genyornis newtoni, appear to
be the most comprehensive amongst Australian megafaunal taxa. Miller et
al. (1999; 2005a) demonstrated G. newtoni extinction in the central arid zone
of Australia around 45 ka. Field and Dodson (1999), Roberts et al. (2001a)
and Trueman et al. (2005) demonstrated that G. newtoni occurs in a more
eastern (currently semi-arid), undisturbed 30 ka deposit (Cuddie Springs)
alongside other megafaunal taxa. Thus, on the basis of that evidence, there
is some support for Horton’s (1984; 2000) climate-change hypothesis in the
geographic and temporal pattern of G. newtoni extinction. Obviously, more
dating from widely separated geographic sites is required to further test that
hypothesis. However, there is some evidence based on other palaeoclimate
proxies to support the broad contention of coastward aridification in the
Pleistocene (Nanson et al., 1992).
Johnson (2005b) considered how interpretations of megafauna extinction
may be changed on the presumption that megafauna survived beyond 46 ka.
He used chronologies presented in Roberts et al. (2001a) and additional
references (see Johnson, 2005b) for megafauna deposits that have been
dated younger than 46 ka and contained disarticulated remains. Although
several Sahulian (Australia-New Guinea) megafauna deposits have been
dated younger than 46 ka, Johnson (2005b) recognised that most of those
48
deposits require rigorous assessment to evaluate the potential for the
reworking of sediments and/or fossil material. Thus, Johnson’s (2005b)
analysis was simply presented as a hypothetical scenario, on the
presumption that those young megafauna deposits have accurate dates and
that the fossil material was not reworked. Johnson (2005b) concluded that
attritional anthropogenic overkill, rather than blitzkrieg or climate change,
drove megafauna extinction. A potentially long overlap between humans and
megafauna automatically refutes a blitzkrieg extinction model (Johnson,
2005b). Additionally, Johnson (2005b) observed that there was no
discernible spatial patterning in megafaunal extinction and rejected Horton’s
(1984; 2000) climate change extinction hypothesis. However, Horton (1984;
2000) only used distance from the coastline as a descriptive proxy for
rainfall, but recognised that precipitation does not uniformally increase from
the continent’s centre outwards (i.e., in many parts of Australia, the current
semi-arid and arid zones extend to the continental margins). Thus, distance
from the current coastline cannot be used as a reliable proxy in the way that
Johnson (2005b) applied it (Wroe & Field, in press). In arriving at his
conclusion, Johnson (2005b) stated that continental megafaunal populations
declined dramatically 50-46 ka following initial human arrival. However, the
data sets utilised by Johnson (2005b) are based primarily on temporal
presence or absence patterns of megafaunal taxa. Data relating to
megafaunal community population dynamics from integrated stratigraphic
successions from many of those late Pleistocene sites, particularly the 50-46
ka deposits, are absent or remain undocumented. Therefore, it is not
possible to analyse the response of specific local populations to human
arrival and/or climate change, nor to demonstrate population declines on the
basis of the available data. Johnson’s (2005b) attritional overkill hypothesis
may also be challenged using the same data set simply by looking at
diversity patterns of megafauna taxa in 50-46 ka deposits versus <46 ka
deposits. Chronologies are available for 12 species in 10 genera for 50-46 ka
deposits, and 22 species in 15 genera for <46 ka deposits (Johnson, 2005b,
and references therein). Thus, rather than a dramatic decline in megafauna
diversity after 50 ka, those data suggest increasing diversity and possible
speciation events alongside a backdrop of increased human presence and
49
climate deterioration during and after the last glacial maximum. Of course,
that is highly unlikely given the dramatic events and unfavourable conditions
surrounding the last glacial maximum. However, this example simply
highlights the need to more rigorously assess new sites and reassess
previously documented sites in terms of reworking and dating, before
extinction hypotheses can be adequately tested using existing data. As
Richard Wright observed in 1990, “megafaunal extinctions is a topic that now
requires rather more digging than talking!” (Wright et al., 1990). Fifteen years
later, the same can still be said for our current understanding of megafaunal
extinctions.
Most other recent hypotheses that support anthropogenic models of
Australian megafauna extinction (e.g., Diamond, 2001; Gillespie, 2002;
Johnson, 2002; Brook & Bowman, 2004; Fiedel & Haynes, 2004; Burney &
Flannery, 2005) rely on similar interpretations and on the conclusions of
Roberts et al. (2001a). Hence, they also are limited by imprecise and
incomplete chronologies. Due to an absence of congruence of chronometric
data, the case for an anthropogenically driven, continent-wide extinction has
yet to be demonstrated. Thus, in order to test specific hypotheses of
megafaunal extinction, it is important to have accurate age estimates of the
last occurrence of each species in various parts of the continent (Grayson,
1989). The establishment of faunal ranges may prove difficult in regions like
Australia owing to the low number of late Pleistocene fossil sites (Dodson et
al., 1993) and the age of many sites being near 40 ka, the practicable limit
for radiocarbon dating. Despite the criticisms directed at the interpretations of
Roberts et al. (2001a), their results add significantly to the understanding of
late Pleistocene extinctions in Australia. Roberts et al. (2001a) recognised
that several other late Pleistocene deposits need to be examined in detail
and dated accurately, a sentiment that has been echoed by many authors
(e.g., Field & Dodson, 1999; Barnosky et al., 2004b; Brook & Bowman, 2004;
Prideaux, 2004; Wroe et al., 2004). More complex models incorporating
detailed ecological analyses at differing regional scales are required to
resolve the issue of megafauna extinction (O’Connell & Allen, 2004; Burney
& Flannery, 2005).
50
DARLING DOWNS
The Darling Downs of southeastern Queensland, Australia, is a critical region
for understanding Australian megafaunal extinctions. It is one of the most
fossiliferous regions in Australia, with more than 50 megafauna-bearing fossil
localities known in a small (16 000 km2) geographic area (Molnar & Kurz,
1997). Roberts et al. (2001a) highlighted the importance of one of its
deposits (site QML783 = ‘Ned’s Gully’) and suggested that it is one of the
youngest in Australia that contains articulated remains of now extinct
megafauna.
Although fossil material has been collected from the Darling Downs since
the 1840’s, shortly following European settlement (Owen, 1877a), few
studies have attempted to document detailed palaeoecological aspects of its
fossil deposits. Although Bartholomai (1976b) and Molnar & Kurz (1997)
presented brief overviews of the Pleistocene faunas of the region, few
studies have addressed detailed stratigraphic, sedimentologic, taphonomic
or palaeoecologic aspects of specific megafauna deposits.
Geographical and geological settings
The Darling Downs is situated west of the Great Dividing Range in
southeastern Queensland. The region is bounded to the north by the Bunya
Mountains, south by the Herries Ranges, and slopes gently westwards into
the plains of central Australia. The Great Dividing Range forms a significant
watershed in eastern Australia and separates several significant drainage
basins. The Darling Downs catchments comprises the upper portion of the
extensive Murray-Darling drainage basin. With its low, rolling hills and plains,
the Darling Downs has today been transformed into a rich agricultural centre,
chiefly associated with grazing, grain and cotton growing. The majority of the
natural vegetation in the area has been altered to some extent by Europeans
(Thompson & Beckman, 1959; Fensham, 1998). However, early pioneers
such as Leichardt (in Bennett 1875) gave an insight into the Darling Downs
prior to the effects of European settlement. Leichardt was awed by the
extensive floodplains covered by grasses and herbs, and noted that open
woodlands were restricted to hillsides. That view was supported by a recent
51
review of vegetative surveys of the region from the early periods of European
settlement (Fensham & Fairfax, 1997).
During the Tertiary, a sequence of volcanic eruptions around the
Toowoomba region produced a series of predominantly basaltic flows
overlying Mesozoic sandstones (Thompson & Beckman, 1959). Dissection
and erosion of the sandstones and basalts during the Tertiary and
Quaternary developed several landforms in the region including the
Toowoomba Plateau, basaltic uplands, steep eastern slopes of the range,
and alluvial floodplains (Thompson & Beckman, 1959). Deep lateritic soils
developed from erosion of basalts along the eastern edge of the range.
Additional erosion of underlying sandstones and basalts led to the
development of dark clay, sand and silt, with abundant calcrete nodules, and
is characteristic of the extensive alluvial plains (Woods, 1960; Gill, 1978).
The sediments are alkaline as evidenced by the high amounts of preserved
calcareous materials (molluscs and calcretes; Gill, 1978). Fossils are
generally derived from the dark clay soils within the floodplains.
The fossil-bearing portion of the Darling Downs is roughly rectangular in
shape, 200 km long and 80 km wide (Molnar & Kurz, 1997). The long axis
runs parallel to the Great Dividing Range. The fossil-bearing portion of the
Darling Downs is divided into two sections (Molnar & Kurz, 1997). The
eastern Darling Downs is underlain predominantly by Pleistocene deposits
and is situated to the east of the Condamine River. The older, Pliocene
Chinchilla Local Fauna is located in the western Darling Downs (Bartholomai
& Woods, 1976).
Macintosh (1967), Gill (1978) and Sobbe (1990) provided limited
stratigraphies for sections along creeks of the eastern Darling Downs,
introducing units termed ‘Toolburra silt’, ‘Talgai pedoderm’ and ‘Ellinthorpe
clay’. However, those names have not seen subsequent use and are not
considered valid stratigraphic units (Baird, 1986; Molnar & Kurz, 1997).
Radiometric and optical dating, and biostratigraphic markers (e.g.,
Diprotodon spp. and Procoptodon spp.) place the age of the deposits within
the Pleistocene (Bartholomai, 1970; Gill, 1978; Molnar & Kurz, 1997;
Mackness & Godthelp, 2001; Roberts et al., 2001a). However, precise
stratigraphic and temporal relationships between Darling Downs deposits,
52
and other southeastern Queensland Pleistocene deposits such as those at
Gore (Bartholomai, 1977) and Texas (Archer, 1978a), are unclear.
Palaeoecology
Early landowners had a general lack of interest in, and knowledge about, the
fossils recovered from Darling Downs deposits, but that did not deter the
efforts of early collectors such as Bennett (Bennett, 1872; 1876) and
Broadbent (de Vis, 1885a). Subsequent collecting from the region continued
at varying rates, with a general focus on the recovery of large-sized
specimens. The majority of fossils recovered from the deposits have been
accessioned into the collections of the Queensland Museum, Brisbane.
Several studies have addressed the taxonomy of Pleistocene faunas from
the region. Several new species were described from the Darling Downs
during the 1800’s such as Meiolania oweni (Woodward, 1888),
Ornithorhynchus agilis (de Vis, 1885b), Diprotodon minor (Huxley, 1862),
and Sthenurus pales (de Vis, 1895). However, several of those species have
since been synonomised with previously erected taxa (e.g., O. agilis de Vis
1885b is a junior synonym of O. anatinus Shaw 1799; Archer et al., 1978).
Work on Darling Downs fossil faunas continued into the early 20th century by
Longman (e.g., 1916; 1924; 1936). More recently, Bartholomai (1963; 1966;
1967; 1970; 1972, 1973a, b; 1975; 1976a) provided seminal taxonomic
reviews of Pleistocene kangaroos and wallabies from the deposits, with
additional contributions from Flannery and Archer (1982; 1983), and
Prideaux (2004); Archer et al. (1978) reviewed the taxonomic status of a
Pleistocene Darling Downs platypus; Baird (1986) described Pleistocene
distributions of birds from the region; Molnar (1990) and Wilkinson (1995)
illustrated fossil material of extinct and extant varanids; and Sobbe (1990)
investigated Pleistocene ecological aspects of predator-prey interactions.
Few attempts have been made to present an overall picture of the region
during the Pleistocene. Both Bartholomai (1976b) and Molnar and Kurz
(1997) suggested that the presence of diverse grazing and browsing
megafauna taxa recovered from the deposits broadly indicated that vast
grasslands and woodlands existed during the Pleistocene. However, Molnar
and Kurz (1997) recognised that past collecting in the region focused on the
53
recovery of large-sized taxa, with smaller forms being overlooked. Hence,
palaeoenvironmental interpretations of Bartholomai (1976b) and Molnar &
Kurz (1997) are limited by the poorly known smaller forms. Since the mid-
1990’s, systematic collecting has focused on the recovery of both large and
small-sized taxa in a variety of deposits from the northern and southern
Darling Downs. The most extensive and diverse faunas have been recovered
from deposits within the Kings Creek catchment (southern Darling Downs).
Those faunas formed the primary focus for my investigation. Whereas
previous palaeoecological studies of Darling Downs fossil vertebrates were
concerned mainly with the taxonomy of fossil species, my project focused on
local and regional palaeoecological aspects of the Pleistocene Darling
Downs.
Kings Creek Catchment
Several Pleistocene megafauna deposits have been recorded in the Kings
Creek catchment (Figure 1). Such deposits are registered as Queensland
Museum Localities (QML) and include exposures in Kings Creek (QML100,
QML796, QML913, QML1396), Budgee Creek (QML782) and Ned’s Gully
(QML783). As with all deposits recorded from the Darling Downs, the
deposits of the Kings Creek catchment are predominantly fluvial in origin.
The preservation of fossil material includes rounded bone pebbles, complete,
but disarticulated skeletal elements, and complete articulated skeletons
(Molnar et al., 1999).
All analytical dating thus far attempted in the catchment confirms that the
deposits are late Pleistocene in age. Hendy et al. (1971) and Gill (1978)
used radiocarbon dating methods to date deposits at Talgai, Dalrymple
Creek, just west of the Kings Creek catchment. Charcoal and calcrete were
dated between 41 and 4 ka. However, megafaunal species were not
reported in association with those dates. Roberts et al. (2001a) used optical
stimulated luminescence (OSL) dating techniques and dated site QML783 (=
‘Ned’s Gully’) to 47 ± 4 ka. Typical Darling Downs megafauna recorded in the
deposit included articulated remains of Diprotodon optatum, Macropus titan,
and Protemnodon roechus (Roberts et al., 2001a). Little analytical dating has
54
been attempted for other deposits in the region. In general, the stratigraphic
relationships between deposits of the Kings Creek catchment are unknown.
Figure 1. Modern Kings Creek Catchment with heights (in metres) of surrounding peaks, the
main deposit (site QML796) and other deposits mentioned in the text (QML). GDR: Great
Dividing Range; KCC: Kings Creek Catchment; QML: Queensland Museum Locality.
Site QML796
I chose site QML796 as a major focus for my investigation of the Pleistocene
palaeoecological aspects of the region (Figure 1). Site QML796 (= ‘Sutton’s
Site’; Molnar & Kurz, 1997) is located in the northern bank of Kings Creek.
The exposed portion of the deposit is approximately 5 metres wide by 2
metres high. Several distinct sedimentary horizons are evident in the deposit.
A tentative stratigraphic assessment of the site suggested that deposition
occurred both in channel and overbank settings, thus allowing the testing of
specific taphonomic hypotheses.
Site QML796 is one of the most fossiliferous deposits in the Kings Creek
catchment. Fossil invertebrate and vertebrate remains are common
throughout each stratigraphic horizon, however, some horizons are more
fossiliferous than others. A diverse fauna was initially collected from the
deposit that included almost 20 taxa including members of the
Velesunionidae, Thiaridae, Teleosti, ?Anura, Chelidae, Agamidae,
55
Varanidae, Crocodylidae, Aves, ?Monotremata, Dasyuridae, ?Peramelidae,
Palorchestidae, Diprotodontidae, Vombatidae, Macropodinae and Muridae
(Molnar & Kurz, 1997). As the stratigraphy of the deposit indicated several
periods of deposition, the site was ideal for the examination of potential
species through time at a single locality. My investigations of site QML796
provided a detailed palaeoecological record of the region, and hence, forms
a baseline for comparison of other deposits, both for the Kings Creek
catchment, and for the broader Darling Downs, thus placing the deposits in a
national context. The Darling Downs may also become a region of
international significance for the testing of hypotheses regarding the global
Pleistocene extinction of the megafauna.
Excavation
Although site QML796 has been known for more than 20 years, collecting
has been dominated by amateur palaeontologists. Such collecting has
focused on the recovery of large-sized specimens, predominantly
megafaunal species, with little consideration of the stratigraphic provenance
of fossil material. Later excavations by the Queensland Museum (QM)
involved the general documentation of the stratigraphic units of the deposit.
Seven main stratigraphic units were identified (designated A1 through A7).
Fossils were recovered by in situ collecting and removal of bulk sediment for
sieving to target smaller specimens. All fossil material was labeled according
to the sedimentary horizon from which it was derived, and >10 m3 of
sediment were processed. The sediment was washed using graded sieves
ranging from 10 mm to 1 mm, and small bones were sorted following
techniques described in Andrews (1990). Such collecting procedures allowed
the recovery and association of both large and small-sized taxa.
More recent QUT-QM excavations involved a ‘top down’ excavation
approach. A 3 x 2 m plot was surveyed on the ground above the site, and 1 x
1 m quadrats were excavated in 10 cm increments using trowels and
brushes. Excavated layers were correlated to stratigraphic units on the
vertical sides of the pit. The excavation continued to the depth of 2.3 m
yielding an additional ~14 m3 of material. That methodology standardised the
56
method of collection and allowed the retrieval of detailed information of
species distributions within the deposit.
The manual sieving and sorting component of fossil material was
particularly time-consuming and labour intensive. However, numerous
volunteers provided assistance in those aspects during the course of the
research. Collectively, they contributed over 15 000 hours in manual labour.
The intensive efforts of such volunteers allowed several thousand kilograms
of sediment to be processed and allowed the retrieval of material and data
that would have been otherwise impossible to obtains in the required
timeframe.
Stratigraphy, sedimentology and taphonomy
The entire exposed section was measured and documented on vertical
surfaces during excavation. A 2.3 metre-long auger was used to probe
surrounding sediment to determine the lateral extent of particular beds.
Sediment samples from each stratigraphic unit were disaggregated using
alternating cycles of bleach and detergent, dried, and sieved using -2 to 4 phi
mesh sizes for grain size analysis. Subsamples were wet sieved to ensure
separation of the mud fraction. Lithofacies and fluvial architectural elements
were identified and assigned facies codes following the technique described
by Miall (1996). Differentiation and identification of calcrete followed Arakel
(1982). The stratigraphic and sedimentologic investigation of the deposit
allowed determination of the precise depositional setting.
Unfortunately, few studies have specifically investigated the depositional
processes and taphonomic modes of fossil accumulation of Australian
megafauna deposits (e.g., Baird, 1991; Long & Mackness, 1994; Van Huet,
1999; Brown & Wells, 2000). Hence, spatial and temporal constraints on the
palaeoecology of prehistoric Australian terrestrial communities are poorly
known, especially including those that encompass late Pleistocene
megafauna extinction. Studies that document taphonomic modes of bone
accumulation are particularly relevant in that they can aid recognition of
reworking and bias related to both accumulation processes and preservation.
Bias in the fossil record may affect diversity estimates, timing of extinction
events, and analysis of palaeobiological and palaeoenvironmental
57
parameters (Behrensmeyer, 1988; Lofgren et al., 1990). Where significant
taphonomic investigations have been undertaken in Australia, they have
primarily focused on megafauna species (e.g., Long & Mackness, 1994; Van
Huet, 1999; Brown & Wells, 2000) or on small-sized mammals that occur in
non-megafaunal deposits (e.g., McDowell, 1997; Kos, 2003a, b). A
significant deficiency exists in the interpretation of accumulations involving
both fluvial fossil deposits and non-mammal terrestrial vertebrate groups,
such as squamates. The latter is also a deficiency associated with
taphonomic studies throughout the world, as studies have generally focused
on mammals, with most other terrestrial vertebrates overlooked. The more
significant taphonomic studies of non-mammal vertebrates have focused on
larger-sized groups such as dinosaurs (e.g., Dodson, 1971; Eaton et al.,
1989; Smith, 1993) and marine reptiles (e.g. Martill, 1985; 1987). It is
generally assumed that the dispersal and accumulation of such groups follow
similar taphonomic pathways to mammals (Martin, 1999). The vertebrate
taphonomic component of this study focused on both mammals and non-
mammal vertebrates from the deposits. Identifiable cranial and post-cranial
material of terrestrial vertebrate species provided the basis for the
taphonomic study. Unidentifiable bone fragments were not used. Better
preserved specimens may yield more accurate palaeobiological and
palaeoecological information than unidentifiable fragments. However, it is
recognised that some components of the assemblages may have had
different taphonomic pathways leading to their final deposition.
The unit of element representation included MNI (minimum number of
individuals; equivalent to NISP [number of identified specimens] following
Badgely, 1986), and MNE (minimum number of elements; Lyman, 1994). For
vertebrates, calculation of MNI was based mostly on dentary and maxillary
remains, except in the case of fish, frogs, turtles and some squamates,
where vertebrae, pelves, carapace/plastron fragments and osteoderms were
used, respectively. I conducted rarefaction analyses on taxon abundance
data for each assemblage to test for potential bias introduced by differences
in sample sizes. Diversity patterns using the rarifed data sets were compared
between assemblages of standardised subsample sizes with independent
Kolmogorov-Smirnov two-sample statistical tests (Jamniczky et al., 2003;
58
Payne, 2003). Additionally, taxon abundance data from each assemblage
were combined, and bootstrapping analyses (1000 replicates with
resampling) were conducted to obtain 95% confidence intervals for the
estimate of N taxa in a given assemblage.
The taphonomic study investigated the range of characteristics relating to
skeletal preservation, relative abundance of skeletal elements, breakage and
fracture patterns, and relative degree of abrasion of fossil material
recovered. Those analyses demonstrated the utility of lithofacies and
depositional environment analysis for interpreting different taphonomic
accumulation patterns of both large- and small-sized taxa within the deposit.
Such analysis was crucial for constraining full palaeoecological information in
the fossil fauna.
Orientation of large freshwater bivalves (Velesunio ambiguus) and bones
generally larger than 2 cm were measured in situ with the angles between
long axes and north recorded. In situ bivalve taphonomy was evaluated
using the coexistence index of left and right valves (Cv) of V. ambiguus. Cv
was calculated using the equation:
1
211V
VVCv
−−= (1)
where V1 is the greater number of valves and V2 is the lesser number of
valves (after Shimoyama & Hamano, 1990). Cv values range between 0 and
1 and measure the deviation from the expected 1:1 ratio. Additionally, χ2
tests were computed to test for preservation differences between bivalves.
The attitude (i.e., concave up or convex up) of V. ambiguus valves was also
documented. Recorded orientations of fossil material allowed for the
documentation of aspects relating to palaeocurrent direction.
Kolmogorov-Smirnov two-sample statistical tests and χ2 analyses, were
performed using SPSS © statistical software. Rarefaction and bootstrapping
analyses were conducted using PAST © statistical software (Hammer et al.,
2001). All correlations were considered to be significant at the 95%
confidence level.
59
Palaeoecology
A multifaceted investigation of the fossil fauna was designed that allowed the
retrieval of high resolution palaeoecological data. Morphological and
morphometrical techniques were used to taxonomically identify and
characterise the fossil material. Comparative specimens were accessible
within the Queensland Museum collections. Ecological aspects of extant taxa
occurring as fossils in the deposit were drawn by analogy to modern
populations. Ecological aspects of extant species were derived from Beesley
et al. (1998) and Lamprell and Healy (1998) for molluscs, Cogger (2000) for
reptiles, and Strahan (1995) for mammals. Ecologies of fossil taxa occurring
in the deposit were largely derived from Bartholomai (1973a; 1975), Murray
(1984; 1991) and Flannery (1990). Previous palaeoenvironmental
interpretations of the Darling Downs have been based on the inferred
ecologies of extinct megafauna (e.g., Bartholomai, 1976b; Molnar & Kurz,
1997). However, extant species that occur in fossil assemblages form a more
rational basis for palaeoenvironmental interpretations (Lundelius, 1983), and
the value of using small-sized taxa in reconstructing past environments is
increasingly being documented (Brothwell & Jones, 1978; Andrews, 1990;
Vigne & Valladas, 1996). Small-size taxa generally have smaller home
ranges, more specific habitat requirements and shorter life spans, making
them more useful for habitat reconstruction than larger-sized taxa. The
small-sized taxa of site QML796 were used in conjunction with megafaunal
species to make interpretations regarding Darling Downs
palaeoenvironments.
Ecological characteristics (e.g., locomotory or feeding behaviours) of
mammalian assemblages within the deposit were calculated. Andrews et al.
(1979) demonstrated that the community structure of modern mammal
communities from similar modern habitat types is consistent, even where a
comparison of taxa between habitat types indicates few or no species in
common. Habitats of mammalian communities can be predicted on the basis
of their ecological diversity. Hence, establishing the community structure of
modern mammal faunas from particular habitats and subsequent
comparison with the community structure of fossil mammal assemblages has
predictive value for assessing palaeohabitats (Andrews et al., 1979). Thus,
60
aspects of community structure of modern Australian mammalian faunas
were compared with the community structure of fossil mammal assemblages
from site QML796, following methodology described in Andrews et al. (1979).
The quantification of ecological relationships between modern and fossil
assemblages were assessed statistically with bivariate Pearson analyses
using SPPS © statistical software. Correlations were considered to be
significant at the 95% confidence level.
The ability to quantify diversity is an important tool when attempting to
understand community structure (Vermeij and Leighton 2003). There are
several different ways to estimate the diversity of an assemblage or
community. One of the most simple diversity estimates is by comparison of
the total number of species recorded between assemblages. However, such
estimates of species richness do not take into account several major aspects
of diversity including equability or evenness of the relative abundance of
species, or heterogeneity of the fauna (Willig, 2003). Several indices have
been developed that attempt to take into account species abundance and
evenness, and may provide important information about rarity and
commonness of particular species within a community or assemblage (Buzas
and Hayek, 2005). Diversity estimates for site QML796 were based on
Simpson, Shannon-Weiner, Pielou, and Whittaker diversity indices, and
MacArthur rank abundance models for terrestrial species from each of the
main fossiliferous horizons.
The Simpson’s heterogeneity index (D) is calculated by the formula:
( )( )
1
11
=
��
���
�
−−
=�
i
NNnn
D
s
ii (2)
where s is the total number of species, ni is the number of individuals i in the
sample, and N is the total number of species in the sample. D ranges
between 0 and 1, and is larger for samples with less heterogeneity. That
relationship is neither logical nor intuitive, so the relationship is inverted with
D being subtracted from 1 so that lower values reflect less heterogeneity
(Rose, 1981).
61
The Shannon-Weiner heterogeneity index (H') is among the most widely
used indices of diversity and is calculated by the formula:
1
ln'
=
−= �i
ppH
s
ii (3)
where s is the total number of species in a sample and p is the frequency of
the ith species. The index is primarily used as a measure of heterogeneity or
mixed diversity, but also reflects evenness.
The evenness component of heterogeneity is measured using several
indices. Among the most simple is Pielou’s evenness index calculated by the
formula:
sH
Jln
'= (4)
The calculation is derived from the result of H' and number of species in the
sample (s).
An additional index of evenness is the Whittaker index (E), which is
calculated using the formula:
( )spps
Eloglog 1 −
= (5)
where s is the number of species, pi is the frequency of the most common
species, and ps is the frequency of the rarest species.
Each diversity index has limitations, but the indices can be highly
informative regarding community structure (Buzas and Hayek, 2005).
Diversity and evenness may also be estimated using hypothetical models
of rank abundance of species within a given community or assemblage. Two
main models of the hypothetical distribution of species within a given
community were developed by MacArthur (1957; 1960). The ‘dependent
model’ (as hypothesis I in MacArthur, 1957) predicts that the relative
abundance of any species is dependent on the relative abundance of all
other species within a fauna. Thus, the relative abundance �
��
mN r of the rth
rarest species is calculated by the formula:
62
( )1
111
=+−
= �
iinnm
Nr
r
(6)
where m is the total number of individuals in a fauna, n is the total number of
species in the fauna, and Nr is the abundance of the rth rarest species. Here,
m is the total MNI and Nr is the MNI of the rth species. If relative abundance
is plotted against the logarithm of the rank abundance, the resulting curve is
nearly linear. MacArthur (1957) demonstrated that certain bird communities
from homogeneously diverse tropical and temperate forests fit the dependent
model hypothesis.
The ‘independent model’ (as hypothesis II of MacArthur, 1957) predicts
that the relative abundance of species r is independent of all other species
within a given fauna. The relative abundance mN r of the rth rarest species is
calculated by the formula:
( ) ( )( )n
rnrnmN r −−+−
=1
(7)
where n is the number of species in the fauna and r is the rank abundance of
species r. Here, rank is based on the abundance rather than rarity such that
1+−= rni . The model predicts that the common species are commoner and
rare species are rarer than that predicted by the ‘dependent model’.
Hutchinson (1961) observed independent model-type distributions of
diatoms, arthropods and plankton species in heterogeneous environments.
Dating
Dating the deposit is a critical aspect of the investigation. Accurate dating is
crucial for testing the previous reported ages for the region, establishing a
reliable chronology for the deposits, and for better understanding the timing
and means of extinction of many species. Dating the succession will also
support investigations of the systematics and phylogenetics of several
species that have Pleistocene records within the deposit. Samples of
bivalves (Velesunio ambiguus), charcoal and bone were submitted to
ANSTO (Australian Nuclear Science and Technology Organisation; Lawson
63
et al., 2000) for the purpose of accelerator mass spectrometry (AMS) 14C
dating. Only complete, conjoined bivalves were submitted for dating, as they
are unlikely to have been reworked from older units. V. ambiguus, like most
Unionoidea, have the ability to burrow (Walker, 1981). Hence, it is possible
that individuals selected for dating could have burrowed into sediment older
than that in which they lived. However, at site QML796, stratigraphic and
sedimentologic sequences are preserved intact and there is no evidence of
extensive burrowing of bivalves (see Chapter 4). Additionally, bivalves
selected for dating included only those that were lying with their valves
horizontal in the sediment and not in ‘growth’ or ‘burrowing’ positions (i.e.,
valves in vertical positions). Those individuals are presumed to have been
deposited in that position and were unlikely to have burrowed into older
sedimentary horizons
Selection of bivalves and charcoal samples for dating followed the dating
selection criteria established by Meltzer and Mead (1985). Samples were
collected from stratigraphic horizons containing megafauna and other small-
sized taxa that were entirely capped above and below by different sediments.
Results obtained from the dating of bivalves or charcoal indicate the
approximate time of deposition.
Bone samples from site QML796 were submitted to ACQUIRE (Advanced
Centre for Queensland University Isotope Research Excellence, University of
Queensland) for U/Th dating. Bone submitted for dating using both AMS 14C
and U/Th dating methods included near complete megafauna crania and
dentaries, isolated teeth, and complete post-cranial elements. Specimens
selected were well-preserved, relatively complete, and unabraded. Hence,
the selection criteria targeted fossil material that was particularly well
preserved, and highly unlikely to have been transported far or reworked. U-
series dating is based on the premise that U is taken up from the
environment by bone apatites that scavenge U, but exclude Th, during
diagenesis. The age is calculated by determining the amount of 230Th that
was produced by the decay of 238U (via intermediate isotope 234U). Since
bones are open systems for uranium, in most cases the U/Th dates
represent the mean ages of the U-uptake history and thus the minimum ages
of deposition (Simpson & Grün, 1998; Thorne et al., 1999; Zhao et al., 2001).
64
Meltzer and Mead (1985) considered that direct dating of fossil bone
represents a ‘strong’ association between fauna and deposition time and is
desirable for securely dating fossil assemblages.
Correlation to other Kings Creek deposits
Other Kings Creek catchment megafauna-bearing deposits were examined
to determine litho- and/or biostratigraphic relationships to QML796. Such
deposits included sites QML100, QML913, QML1396 (Kings Creek),
QML782 (Budgee Creek), and QML783 (Ned’s Gully) (Figure 1). Fossil
material was previously collected from each of those deposits and was
available for study in the Queensland Museum. However, additional material
was also collected from each of those localities using excavation techniques
similar to those utilised at site QML796, but to a lesser magnitude.
Stratigraphic, sedimentologic, taphonomic and palaeoecologic characteristics
were examined based on techniques used at QML796. Due to financial
constraints, analytical dating was attempted only for QML796 and QML1396.
The ultimate aim of such correlations was to provide a chronology for the
depositional history of Kings Creek catchment fossil deposits. Biocorrelation
between sites may allow species to be studied at varying temporal and
spatial scales.
SUMMARY
The ability to answer questions regarding ancient populations and species
may allow us to anticipate changes in modern ecosystems subject to
environmental change (Barnosky et al., 2004a). Environmental records that
have been derived through the investigation of Quaternary environments and
the mechanisms that have been proposed to account for the observed
changes, provide a vital resource for modeling an understanding of the
global environment (Willis et al., 2004). Additionally, the knowledge of both
the history and modern conditions of lineages are required to best determine
a species’ current conservation status and make reasoned predictions about
its future survival.
65
Essentially, to resolve the issue of late Pleistocene Australian megafauna
extinction, several issues require investigation including: 1) the temporal and
spatial extinction patterns of megafaunal species (Horton, 1984; Grayson,
1989; Gonzalez et al., 2000; Stuart et al., 2002; 2004); 2) the temporal and
spatial patterns of arrival and dispersal of human colonisers in Australia
(O’Connell & Allen, 2004); 3) determining what megafaunal species co-
occurred with humans and the nature of the interaction (direct [e.g. hunting]
or indirect [e.g. habitat modification via burning]) (Horton, 1984; Field &
Dodson, 1999; Prideaux, 2004; Arroyo-Cabrales et al., 2006); 4) determining
whether that interaction was a casual factor for the extinction (Trueman et
al., 2005); and 5) discriminating anthropogenic factors from natural inherent
climatic variability (Diamond, 1989b; Burney & Flannery, 2005). Confusion
surrounding the timing and causes of Australian megafauna extinctions is
due primarily to the paucity of well-dated late Pleistocene megafauna
deposits. A combination of more rigorous dating and increasingly complex
models incorporating detailed ecological analyses at differing regional scales
are required to resolve the issue of megafauna extinction.
Previous investigations of the Pleistocene Darling Downs place the age of
the deposits close to the terminal extinction ‘event’ of the megafauna. Hence,
detailed investigation of its deposits and Pleistocene faunas may have
critical implications for the understanding of regional and continental
megafauna extinction.
66
PUBLISHED PAPERS / SUBMITTED MANUSCRIPTS
Paper 1. PRICE, G.J. 2005 (2004)a. Fossil bandicoots (Marsupialia,
Peramelidae) and environmental change during the Pleistocene on the
Darling Downs, southeastern Queensland, Australia. Journal of Systematic
Palaeontology. 2: 347-356.
This chapter documents the geographic sampling area of the Pleistocene
Kings Creek catchment. Additionally, late Pleistocene Darling Downs
climates and habitats are interpreted based on fossil bandicoot
assemblages.
Contribution of authors
I collected, prepared and identified most of the material that was examined in
this paper (with additional support from others noted in the
Acknowledgements). I also supervised labouring efforts of the volunteers
who assisted in the preparation of fossil material. Additionally, I prepared the
original and final manuscript for publication.
67
Journal of Systematic Palaeontology 2 (4): 347–356 Issued 26 January 2005
DOI: 10.1017/S1477201904001476 Printed in the United Kingdom C© The Natural History Museum
Fossil Bandicoots (Marsupialia,
Peramelidae) and environmental
change during the Pleistocene on
the Darling Downs, southeastern
Queensland, Australia
Gilbert J. PriceQueensland University of Technology, School of Natural Resource Sciences, GPO Box 2434, Brisbane,Queensland, Australia 4001
SYNOPSIS Systematic collecting from fluviatile Pleistocene fossil deposits of the Darling Downs,southeasternQueensland, Australia, has led to an increase in the region’s fossil record of bandicoots.Isoodon obesulus, Perameles bougainville and P. nasuta are reported for the first time in the DarlingDowns fossil record. Accelerator mass spectrometry 14C dates based on charcoal from bandicootfossil-bearing stratigraphic horizons indicates deposition 45–40 ka. Additional material attributed tothe recently described Darling Downs P. sobbei is also described. P. sobbei retains plesiomorphiccharacters in theupperdentition including reductionof themetaconuleonM3 and the lackofposteriorcingula on M2 and M3. Phylogenetic interpretation of dental characters suggests that P. sobbei hascloser affinities to the Pliocene P. bowensis than to any modern species. The presence of extantspeciessuchasP.bougainvilleand I. obesulusas fossilsprovidesevidence thatscrublandsandclosedwoodlandswith dense understories existed on the Darling Downs during the Pleistocene. The DarlingDowns bandicoot assemblage represents the only known fauna, fossil or modern, where I. obesulus,P.bougainvilleandP.nasutaoccursympatrically. ThePleistoceneDarlingDownsmayhavehadamoreequable climate than occurs today and a greater range of habitat niches to support such populations.The southern and western contraction of the geographical ranges of I. obesulus and P. bougainvillebetween the Pleistocene and the present was probably the result of significant environmental changethat may have involved the contraction of woodlands and expansion of grasslands. The persistenceof P. nasuta populations on the Darling Downs from the Pleistocene to the present may reflect thatspecies’ ability to adapt to a wide range of habitats.
KEY WORDS Isoodon, Perameles, non-analogue assemblage, Kings Creek catchment
E-mail:[email protected].
Contents
Introduction 348
Geography and stratigraphy 348
Materials and methods 348
Systematic palaeontology 349Supercohort Marsupialia Cuvier, 1817 349Cohort Australidelphia Szalay, 1982 349
Order Peramelemorphia Kirsch, 1968 349Family Peramelidae Gray, 1825 349Genus Isoodon Desmarest, 1817 349
Isoodon obesulus Shaw, 1797 349Genus Perameles Geoffroy, 1804 351
Perameles bougainville Quoy & Gaimard, 1824 351Perameles nasuta Geoffroy, 1804 352Perameles sobbei Price, 2002 352
Discussion 353
Acknowledgements 355
References 355
68
348 G. J. Price
Introduction
Palaeoenvironmental interpretations of past climates and cli-mate change are commonly based on fossil assemblages thatcontain extant species with known environmental tolerances.Such interpretations are generally based on the assumptionthat species have not undergone significant biological orphysiological change over time. It is clear that many ex-tant taxa have experienced major shifts in their geograph-ical distributions since the Late Pleistocene, indicating thattheir environmental tolerances in a particular area may havechanged (Lundelius 1983, 1989; Graham et al. 1996; Staffordet al. 1999). However, evolutionary tracking of biologicalor physiological change in extant species over time in re-sponse to environmental change, would probably result inno alteration to their Pleistocene geographical distributions(Lundelius 1983). That hypothesis is difficult to assess andmay limit the precision of palaeoenvironmental interpreta-tions that are based on extant taxa occurring as fossils, butdoes not necessarily invalidate them (Lundelius 1983).
Complications commonly occur where fossil as-semblages contain extant species that provide conflicting in-formation about past climates. Many late Pleistocene fossilassemblages are characterised by the coexistence of extantspecies that today show allopatric geographical distributions(Graham & Lundelius 1984). For example, Dyrovaty KamenCave, Russia, contains the pied lemming (Dicrostonyxgulielmi near D. torquatus), a species presently confinedto arctic tundra, as well as the steppe lemming (Laguruslagurus), an inhabitant of grasslands (Stafford et al. 1999).Those species have completely allopatric distributions today,separated by over 1000 km and they occupy distinctly dif-ferent habitats. Similar types of conflicting faunal associ-ations are common throughout Eurasia, Africa, America andAustralia (Lundelius 1983, 1989; Graham & Lundelius1984). Semken (1974) used the phrase ‘disharmonious’ todescribe those fossil associations of extant species that haveno analogue with modern communities. Non-analogue as-semblages are generally time restricted, being quite commonin Late Pleistocene deposits, but rare in Holocene deposits,suggesting that most modern biomes are Holocene in age(Lundelius 1989; Stafford et al. 1999). Non-analogue asso-ciations of fossil species that provide conflicting informationabout palaeohabitats are generally interpreted as indicatinggreater habitat diversity or patchiness and such greater di-versity may have been maintained by more equable climateswith less seasonality (Lundelius 1983, 1989). Climatic in-terpretations of non-analogue assemblages are based on theassumptions that: (i) faunas, particularly mammals, are notdirectly affected by climates, but by availability of vegetationfor food and shelter and that is, in turn, affected by climate(Graham et al. 1996) and (ii) geographical ranges of extantspecies are well known (Lundelius 1983). However, the doc-umentation of geographical distributions of extant taxa hasbeen compromised in some areas such as Australia owingto the rapid contraction and disappearance of sensitivetaxa in many areas immediately following European settle-ment. Australian examples include the contraction of therange and subsequent mainland extinction of the western-barred bandicoot (Perameles bougainville) and the absoluteextinctions of the thylacine (Thylacinus cynocephalus) andToolache wallaby (Macropus greyi: Friend & Burbidge 1995;Rounsevell & Mooney 1995; Smith 1995). In contrast,
post-European settlement and pastoral activities have ledto increases in the distributions of other species such asthe eastern grey kangaroo (M. giganteus: Poole 1995). Theaim of this paper is to discuss the taxonomy and palaeoen-vironmental significance of an assemblage of fossil bandi-coots, a group of rabbit-sized terrestrial vertebrates in thefossil record of the Pleistocene Darling Downs, southeasternQueensland, Australia.
The Darling Downs is renowned as a rich source ofPleistocene vertebrate fossils. Megafaunal species such asthe rhinoceros-sized Diprotodon and giant kangaroos, in-cluding Procoptodon and Protemnodon, are well representedin the deposits, although small-sized species remain poorlyknown. Recent systematic collecting from various DarlingDowns fossil deposits have begun to yield both megafaunaltaxa as well as small-sized taxa including land snails, frogs,skinks, agamids and small mammals (Price 2002). Amongthe more interesting discoveries were new records of Pleis-tocene bandicoots that included a new species of long-nosedbandicoot, P. sobbei (Price 2002). More recent systematiccollecting from the P. sobbei type locality (QML796) andan additional fluviatile fossil deposit (QML1396: See Fig. 1)has led to further additions to the Darling Downs Pleistocenebandicoot fossil record, including examples of species thathave modern allopatric distributions.
Geography and stratigraphy
The Darling Downs, southeastern Queensland, encompasseslow rolling hills and plains west of the Great Dividing Range.The Great Dividing Range extends along the eastern seaboardof Australia (Fig. 1) and is responsible for the extreme cli-matic regimes experienced between central and eastern coa-stal Australia. Darling Downs sediments consist of clays, siltsand sands derived from erosion of underlying Miocene basaltflows and Mesozoic sandstones (Woods 1960; Gill 1978).
The Kings Creek catchment, southern Darling Downs,contains the most abundant and extensive vertebrate fossildeposits of the region (Molnar & Kurz 1997). The mod-ern Kings Creek catchment, bounded to the north, east andsouth by the Great Dividing Range, is fed by several mainlydry or intermittent watercourses (Fig. 1). Two fossil depos-its (QML796 and QML1396) located in the Kings Creekcatchment, formed the focus for the investigation (Fig. 1).Both deposits consist of fluvially transported sediments andare interpreted as representing channel and overbank de-posits. Samples of charcoal from both deposits were sub-mitted to ANSTO = Australian Nuclear Science and Tech-nology Organisation. AMS = accelerated mass spectrometry(Lawson et al. 2000) for the purpose of AMS14C dating.The QML1396 bandicoot fossil-bearing horizon was datedto 45 150 ± 1200 years ago (OZG855). A horizon overlyingthe main bandicoot fossil-bearing horizon at QML796 wasdated to 40 000 ± 750 years ago (OZG853), thereby provid-ing a minimum age for fossil bandicoots from the deposit.
Materials and methods
Fossils were recovered from distinct stratigraphic horizonsby the removal of sediment to target smaller fossil specimens.The sediments were washed using graded sieves of 10 mmto 1 mm and small bones were sorted following similar tech-niques to those described in Andrews (1990).
69
Fossil Bandicoots and environmental change 349
Figure 1 Modern Kings Creek Catchment with heights (in metres) of surrounding peaks and deposits (QML) where fossil bandicoot remainswere recovered. GDR, Great Dividing Range; KCC, Kings Creek Catchment; QML, Queensland Museum Locality.
Dental nomenclature follows Luckett (1993), where theadult unreduced cheek tooth formula of marsupials is P1−3
and M1−4 in both upper and lower dentitions. Tooth mor-phology follows Archer (1976). Higher systematics followAplin & Archer (1987). Features distinguishing Isoodon andPerameles are outlined in Smith (1972) and Archer (1978).Referred material is deposited in the Queensland Museum(QMF) under Queensland Museum Localities (QML).
Systematic palaeontology
SupercohortMARSUPIALIA Cuvier, 1817Cohort AUSTRALIDELPHIA Szalay, 1982Order PERAMELEMORPHIA Kirsch, 1968
Family PERAMELIDAE Gray, 1825Genus ISOODON Desmarest, 1817
Isoodon obesulus Shaw, 1797 (Figs 2A, B; Table 1)
REFERRED MATERIAL. QMF44548, isolated LM1;QMF44547, right dentary with RM3; Both from QML796.
DIAGNOSIS. See Lyne & Mort (1981).
DESCRIPTION.
Dentary. Deepest below M3; horizontal ramus broken anteri-orly to M1 anterior alveolus and posteriorly just past anterioredge of masseteric fossa; mental foramen small, anterovent-ral to anterior alveolus of M1; vertical ramus approximately115◦ to horizontal ramus.
LM1. Sub-rectangular in occlusal outline; talonid markedlywider than trigonid; relative heights of cuspids indetermin-
Table 1 Measurements of fossil bandicoot molar teeth fromQML796 and QML1396, Darling Downs.
Species QMF Tooth Length Ant. width Post. width
Isoodon obesulus 44548 LM1 3.34 1.80 2.35Isoodon obesulus 44547 RM3 3.78 2.27 2.29Perameles 44549 RM1 2.89 1.58 1.95bougainville
Perameles 44550 RM3 – 1.83 1.88bougainville
Perameles nasuta 44567 RM1 3.62 1.91 2.33Perameles nasuta 44568 RM1 3.43 – 2.52Perameles nasuta 44566 LM3 4.20 2.50 2.56
All measurements are in mm. Length is the anterior-posterior distance. Ant.width is the lingual–buccal distance across the trigonid. Post. width is thelingual–buccal distance across the talonid.
ate due to wear; paraconid forms anterior margin of tooth,entirely lingual to midline; metaconid posterolingual toparaconid; protoconid occupies buccal portion of trigonid,slightly anterobuccal to metaconid; entoconid lies directlyposterior to metaconid; hypoconid lies posterobuccal to pro-toconid; entoconid and hypoconid on the same transverseplane; hypoconulid prominent, posterior to entoconid; formof posthypocristid and cristid obliqua obliterated by wear;buccal surface of tooth is curved lingually with enamel ex-tending to base of crown.
RM3. Sub-rectangular in occlusal outline; trigonid andtalonid are of a similar width; metaconid is tallest cusp fol-lowed in descending order by protoconid, entoconid, para-conid, then hypoconid; paraconid just posterior to anterior
70
350 G. J. Price
Figure 2 Darling Downs fossil bandicoot teeth. A, Isoodon obesulus, right dentary, QMF44547, lingual view; B, buccal view; C, Peramelesbougainville, RM1, QMF44549, occlusal view; D, P. nasuta, LM3, QMF44566, occlusal view; E, P. sobbei, RM2, QMF21680, occlusal view;F, P. sobbei, LM3, QMF44569.
margin, positioned lingual to midline; metaconid directlyposterior to paraconid; metaconid and protoconid are in sametransverse plane; entoconid directly posterior to metaconid;hypoconid directly posterior to protoconid; entoconid andhypoconid are in the same transverse plane; hypoconulidreduced or absent; posthypocristid runs posterolingually toposterior base of entoconid; cristid obliqua descends antero-lingually from apex of hypoconid, curving slightly to termi-nate in the midvalley at posterobuccal base of metaconid; an-terior cingulid high on anterior face of paraconid, rounded inits lingual corner, tapering buccally to terminate at theanterobuccal base of protoconid; small buccal cingulidpresent at anterobuccal base of hypoconid; buccal surfaceof tooth curved lingually with enamel extending to base ofcrown.
REMARKS. The morphology of the Darling Downs ma-terial is well within that exhibited by extant populations(Tables 1 & 2). Isoodon obesulus is easily distinguished fromall other Isoodon species by: (i) being intermediate in its size
Table 2 Mean and observed range of measurements of modern bandicoot molar teeth.
Species Tooth Length Ant. width Post. width
Isoodon obesulus M1 3.23 (3.08–3.42) 1.81 (1.74–1.90) 2.27 (2.15–2.37)Isoodon obesulus M3 3.56 (3.38–3.80) 2.45 (2.19–2.49) 2.47 (2.27–2.56)Perameles bougainville M1 2.91 (2.79–3.03) 1.53 (1.48–1.58) 1.90 (1.85–1.95)Perameles bougainville M3 3.04 (2.94–3.14) 1.88 (1.82–1.94) 1.94 (1.86–2.02)Perameles nasuta M1 3.44 (3.25–3.64) 1.95 (1.8–2.04) 2.39 (2.24–2.53)Perameles nasuta M3 3.96 (3.82–4.23) 2.42 (2.37–2.53) 2.48 (2.40–2.58)
All measurements are means in mm, with range in parentheses. Length is the anterior–posterior distance. Ant. width is the lingual–buccaldistance across the trigonid. Post. width is the lingual–buccal distance across the talonid. Measurements of Isoodon obesulus and Peramelesnasuta teeth are based on modern comparative material within the Queensland Museum and were adapted from Freedman (1967b) forP. bougainville.
between the larger I. macourous and smaller I. auratus and(ii) possessing a wider angle of the ascending ramus (Lyne &Mort 1981).
Isoodon obesulus is generally regarded as a nocturnalspecies feeding on earth worms and other invertebrates, in-sects, fungi and subterranean plant material (Braithwaite1995). Extant populations prefer sclerophyllous woodlandswith scrubby vegetation or areas with low ground coverthat are burnt out periodically (Menkhorst & Seebeck 1990;Braithwaite 1995). Braithwaite (1995) suggested that afterfire, growing vegetation supports abundant insect food andthat forms a favourable habitat for I. obesulus.
The presence of Isoodon obesulus in the Pleistocenedeposits of the Darling Downs fills a significant spatial gapbetween extant populations from southern Australia and farnorth Queensland suggesting it had a more complete distri-bution in the past (Fig. 3). It is probable that additional sys-tematically collected Pleistocene fossil deposits north andsouth of the Darling Downs will reveal additional informa-tion about the past distribution of I. obesulus populations.
71
Fossil Bandicoots and environmental change 351
Figure 3 Extant and sub-fossil geographical distributions of bandicoot species that occur in Darling Downs fossil deposits, with otherAustralian Pleistocene deposits where combinations of those species occurred sympatrically.
Genus PERAMELES Geoffroy, 1804
Perameles bougainville Quoy & Gaimard, 1824(Fig. 2C; Table 1)
REFERRED MATERIAL. QMF44549, isolated RM1, QML1396,King Creek; QMF44550 isolated RM3, QML796, KingCreek.
DIAGNOSIS. See Freedman (1967a).
DESCRIPTION.
RM1. Sub-rectangular in occlusal outline; talonid slightlywider than trigonid; metaconid, protoconid and entoconidsub-equal in height, followed in descending order by para-conid, then hypoconid; paraconid forms anterior margin oftooth positioned slightly lingual to midline; metaconid pos-terior and slightly lingual to paraconid; protoconid occu-pies buccal portion of tooth, slightly anterobuccal to meta-conid; entoconid conical in shape, directly posterior to meta-conid; hypoconid posterobuccal to entoconid; hypoconulidlarge at posterior base of entoconid; posthypocristid incom-plete but may be an artefact of preservation; cristid obliquadescends anterolingually from apex of hypoconid, curvingslightly buccally to terminate at posterobuccal base ofprotoconid.
RM3. Anterior portion of trigonid broken; trigonid andtalonid approximately equal in width; heights of cuspids in-
determinate due to wear, although trigonid cuspids appearto be higher than talonid cuspids; hypoconulid at posteriorbase of entoconid; posthypocristid terminates at posterobuc-cal base of entoconid. All other distinguishing characters areeither not preserved or obliterated by wear.
REMARKS. The teeth described here are morphologically andmorphometrically similar to those from extant populationsof P. bougainville (Tables 1 & 2). Perameles bougainville isdistinguished from all modern species by a combination offeatures including: (i) its small size and (ii) more equidistanttrigonid cuspids. It is similar in lower molar morphology tothe Pliocene P. bowensis (Muirhead et al. 1997), but is distin-guished from it by (i) its larger size and (ii) less equidistanttrigonid cuspids. A broken RM3 (QMF44550) is referred toP. bougainville based on its small size.
Perameles bougainville is a nocturnal species, with ex-tant populations occurring only on Bernier and Dorre Is-lands, Shark Bay, Western Australia, although it once oc-curred throughout much of southern Australia (Ashby et al.1990; Kemper 1990; Menkhorst & Seebeck 1990; Friend &Burbidge 1995: Fig. 3). Post-European extinction on themainland of Australia may be attributed to land clearance andpredation from feral species such as cats and foxes (Friend &Burbidge 1995). Extant populations are commonly associ-ated with scrub and open steppe habitats, although it wasonce found on the continent in dense scrub thickets, opensaltbush and bluebush plains and on stoney ridges bordering
72
352 G. J. Price
scrubland (Friend & Burbidge 1995). It is generally regardedas a semi-arid species.
The presence of P. bougainville in the Darling DownsPleistocene extends its previously known northeastern record(Fig. 3).
Perameles nasuta Geoffroy, 1804 (Fig. 2D; Table 1)
REFERRED MATERIAL. QMF44567-8, isolated RM1s;QML796, King Creek; QMF44566 isolated LM3, QML1396,King Creek.
DIAGNOSIS. See Freedman (1967a).
DESCRIPTION.
RM1. Anterior one-third triangular, remainder sub-rectangular in occlusal outline; talonid wider than tri-gonid; protoconid tallest cusp followed in descendingorder by metaconid, paraconid, hypoconid and ento-conid; paraconid forms anterior margin of tooth, po-sitioned slightly lingual to midline; metaconid poster-olingual to paraconid; protoconid occupies buccal por-tion of trigonid, on the same transverse plane as meta-conid; entoconid directly posterior to metaconid; hypo-conid posterobuccal to protoconid; hypoconid slightly pos-terobuccal to entoconid; hypoconulid at posterobuccalbase of entoconid; posthypocristid extends from hypo-conid to midline of posterior base of entoconid; cristid obli-qua straight, descending anterolingually from hypoconid toterminate at posterolingual base of protoconid; anterior andposterior cingula absent.
RM3. Sub-rectangular in occlusal outline; trigonid andtalonid of approximately equal width; protoconid tallest cuspfollowed in descending order by metaconid, paraconid, ento-conid and hypoconid; paraconid slightly posterior to an-terior margin; metaconid slightly posterolingual to para-conid; metaconid and protoconid on same transverse plane;entoconid directly posterior to metaconid; hypoconid dir-ectly posterior to protoconid; hypoconid slightly posterior totransverse entoconid; hypoconulid at posterior base of ento-conid; posthypocristid runs posterolingual to posterobuccalbase of entoconid; cristid obliqua straight, terminating at pos-terobuccal base of metaconid; anterior cingulid low on baseof crown, tapering buccally to terminate at anterobuccal baseof crown.
REMARKS. The lower molars of P. nasuta are distinguishedfrom all other Perameles (excepting the relatively larger Plio-cene P. allinghamensis where the lower dentition is unknown)by its larger size. Perameles nasuta is most similar in size toP. gunnii but is distinguished from that species by possessinga broader anterior cingulid that results in a more rectangu-lar occlusal outline of the lower molar teeth. Lower molarsdescribed here are morphologically and morphometricallysimilar to the corresponding teeth of individuals from extantpopulations (Tables 1 & 2).
Extant populations of P. nasuta have wide ranging hab-itat tolerances, being recorded from rainforest to closed andopen woodlands, to areas with little ground cover (Lavery &Grimes 1974; Stoddart 1995).
Extant P. nasuta populations have been recorded on theDarling Downs (Van Dyck & Longmore 1991: Fig. 3).
Table 3 Measurements of referred P. sobbei uppermolar teeth from QML796, Darling Downs.
QMF Tooth Length Width
21680 RM2 3.86 –44569 LM3 4.13 3.8044570 LM3 4.08 3.9944571 LM3 3.85 –
All measurements are in mm. Length is the anterior-posteriordistance. Width is the maximum lingual–buccal distance.QMF, Queensland Museum Fossil accession code.
Perameles sobbei Price, 2002 (Figs 2E & 2F;Table 3)
REFERRED MATERIAL. QMF21680, isolated RM2;QMF44569-71, isolated LM3s; all from QML796,King Creek.
DIAGNOSIS. See Price (2002), with the addition of: (i) meta-conule on M3 reduced in comparison to similar sized species,(ii) anterobuccal and posterobuccal corners of M3 less exten-ded, (iii) anterior cingulum on M2 short, absent on M3 and(iv) posterior cingula absent on M2 and M3.
DESCRIPTION.
RM2. Sub-triangular in occlusal outline; shallow ectoflexus;metacone tallest cusp followed in descending order by St D,St B, St A, metastylar tip and paracone. Comparison ofheights of metaconule and protocone not possible as lin-gual portion of tooth broken; St A forms anterobuccal cornerof tooth; St B posterolingual to St A; paracone postero-lingual to St A and anterolingual to St B; St D directlyposterior to St B; metastylar tip posterobuccal to St D;metacone lies posterolingual to paracone, transversly pos-terolingual to St D and anterolingual to metastylar tip; pre-paracrista curves anteriorly to connect to St A; postparacristaslightly shorter in length compared to preparacrista, runsposterobuccally to connect to St B; premetacrista runs trans-versely across tooth to link metacone and St D; postmetac-rista run posterolingually to link metacone and metastylar tip;preprotocrista terminates at anterolingual base of paracone;posthypocrista terminates at postlingual base of metacone;anterior cingulum short, below and buccal to midpoint ofpreparacrista.
LM3. Triangular in occlusal outline with posterior surfaceshortest of three crown dimensions; deep ectoflexus; shal-low inflexion between protocone and metaconule; metaconetallest cusp followed in descending order by St D, St B, St A,metastylar tip, protocone and metaconule; St A forms anter-obuccal corner of tooth; St B posterolingual to St A; paraconeposterolingual to St A and anterolingual to St B; St D dir-ectly posterior to St B; metastylar tip posterobuccal to St D;metacone lies posterolingual to paracone, transversely pos-terolingual to St D and anterolingual to metastylar tip; pro-tocone lies directly lingual to paracone; metaconule greatlyreduced lying posterobuccal to protocone and anterolingualto metacone; preparacrista straight, connecting paracrista andSt A; postparacrista shorter than preparacrista and connects toparacone to St B; premetacrista short, directed anterobuccallyfrom metacone, terminating at anterolingual base of St D;postmetacrista straight, connecting metacone and metastylar
73
Fossil Bandicoots and environmental change 353
tip; preprotocrista terminates at anterolingual base of para-cone; posthypocrista absent; anterior and posterior cingulaabsent.
REMARKS. The new upper molars described here are placed inPerameles rather than Isoodon because they possess smallermetaconules on M2 and M3 (Smith 1972), less extendedanterobuccal and posterobuccal corners on M2 and M3 andthey lack complete anterior and posterior cingula on M2 andM3. The upper molars are placed in P. sobbei based on: (i)correlation of size between lower and upper molar teeth and(ii) by being morphologically distinct from all other knownspecies of Perameles.
Perameles sobbei is distinguished from P. bowensis,P. bougainville and P. eremiana by being much larger andfrom the poorly known P. allinghamensis by its smaller size.
Perameles sobbei is most similar in size to the extantP. nasuta and P. gunnii, but differs from those species bypossessing a combination of features including: (i) smallermetaconule on M3, (ii) less extended anterobuccal and pos-terobuccal corners on M2 and M3, (iii) lacking anterior andposterior cingula on M2 and M3 and (iv) preprotocrista con-necting to the anterolingual base of paracone.
Perameles sobbei is so far restricted to the type locality(QML796), despite specific searches for it at other DarlingDowns fossil localities. Morphological variation required toinclude P. sobbei in any other species of Perameles is muchgreater than that known in any single Perameles species,fossil or extant. Therefore, P. sobbei is regarded as a validspecies rather than a highly variable population of a previ-ously recognised Perameles species.
AFFINITIES. Perameles sobbei shares a combination of ple-siomorphic and apomorphic characters with most modernPerameles species. Perameles sobbei is morphologically sim-ilar to the Pliocene P. bowensis and extant P. bougainville as itpossesses a reduced metaconule on M3, a condition regardedas plesiomorphic by Muirhead (1994) who noted the autapo-morphic trait is for the metaconule to be almost as large asthe protocone.
Perameles sobbei and P. bowensis retain the ple-siomorphic character of lacking a posterior cingulum on M2
and M3, a condition that is also exhibited in plesiomorphicdidelphoids and dasyuroids. Modern Perameles are moreapomorphic in that character, as they possess better de-veloped posterior cingula. Muirhead (1994) considered thatthat feature is partially independent to the development ofthe metaconule, as evidenced in other species of bandicoots.
Perameles sobbei and P. bowensis are the only membersof the genus where the preprotocrista connects to the anter-olingual base of the protocone, a condition that also occursin plesiomorphic dasyuroids. The apomorphic condition isexhibited by all modern Perameles where the preprotocristacontinues past the anterolingual base of the paracone andterminates below the midline of the preparacrista.
Perameles bowensis is more plesiomorphic thanP. sobbei as it exhibits poor trough development betweenSt. B and St. D in the upper molars. However, on the basisof the synapomorphic condition of the reduction of thehypoconulid on M1 and absence from M3 (Price 2002),P. sobbei and P. bowensis are regarded as sister taxa andform a sister clade to all Recent Perameles. In addition, bothspecies are regarded as being more plesiomorphic than Re-cent Perameles as they retain plesiomorphies in the upper
dentition including (i) reduced metaconule on M3, (ii) lack-ing posterior cingula on M2−3 and (iii) shorter preprotocrista;and in the lower dentition by possessing equidistant trigonidcuspids (Price 2002).
The relationship between P. sobbei and the PlioceneP. allinghamensis is unclear. P. allinghamensis is so farknown only from an isolated M2 that is markedly larger thanthe corresponding tooth of all other species of Perameles.It is unique in that it is the only member of the genus thatpossesses the apomorphic character of a complete anteriorcingulum on M2 (Archer 1978). However, the anterior cingu-lum of M2 is lower on the crown than that of all other knownPerameles, a feature considered to be plesiomorphic (Muir-head et al. 1997). In addition, the preparacrista and para-stylar corner of the crown is arranged entirely differentlyto all other known species of Perameles (Muirhead et al.1997). It is for such reasons that Archer (1978) suggestedthat additional material may indicate that P. allinghamensismay actually represent a new genus of bandicoot.
Discussion
Early species lists of Darling Downs Pleistocene vertebratefaunas are dominated by extinct megafaunal taxa such asDiprotodon, Protemnodon and Macropus titan (Bartholomai1976, 1977), with small-sized forms such as bandicoots be-ing overlooked. However, since systematic collecting com-menced on the Darling Downs fossil deposits in 1997, extens-ive faunas containing small-sized taxa have been collectedthat include more samples of extant species (Molnar & Kurz1997; Price 2002). This paper extends those results with theextant species Isoodon obesulus, Perameles bougainville andP. nasuta being recognised in the Darling Downs Pleistocenefossil record for the first time.
Isoodon macrourus remains absent in the DarlingDowns fossil record despite the occurrence of extant popula-tions in the region (Van Dyck & Longmore 1991). Its absencein the Darling Downs fossil record may be explained by threehypotheses: (i) suitable habitat to support its populations waslacking on the Darling Downs during the Pleistocene; (ii) itwas out-competed for resources by other species such asI. obseulus that share a similar ecology or (iii) it occurredbut has not been sampled. Extant I. macrourus has a similardistribution to P. nasuta (Gordon et al. 1990) and both spe-cies occur in a wide variety of habitats. Hence, I. macrourusmight be expected to have occurred with P. nasuta in theDarling Downs fossil deposits. Extant I. macrourus andI. obesulus populations occur sympatrically in far northQueensland, possibly ruling out the competitive exclusionhypothesis. However, Gordon & Hulbert (1989) suggestedthat when some bandicoot species occur in areas of sympatry,habitat utilisation may be slightly different from those areaswhere they occur allopatrically. Regardless, the favoured hy-pothesis is that I. macrourus was missed during sampling.
Previous Darling Downs palaeoenvironmental analyseshave been based on interpreted ecologies of extinct mega-fauna. Previous investigations have suggested that the Pleis-tocene Darling Downs was composed of expansive grass-lands, as inferred by the wide range of grazing species, al-though some woodlands must have existed to support less di-verse populations of browsing taxa (Bartholomai 1973, 1976;Archer 1978; Molnar & Kurz 1997). Creeks and watercoursesmay have been larger in order to support the populations
74
354 G. J. Price
of crocodiles that are represented in the fossil deposits(Molnar & Kurz 1997). Recently recovered small-sizedfossil taxa are beginning to demonstrate that Darling Downspalaeoenvironments were more complex than originallythought (Price 2003; Price & Sobbe 2003) and the value ofusing small-sized taxa in reconstructing past environmentsis increasingly being documented (Brothwell & Jones 1978;Andrews 1990; Vigne & Valladas 1996).
Extant species that occur in fossil assemblages forma rational basis for palaeoenvironmental reconstructions(Lundelius 1983). Interpreted ecologies of fossil bandicoottaxa drawn by analogy with extant bandicoot populations al-low additional palaeoenvironmental inferences to be madeabout the Darling Downs Pleistocene environments. In thecase of the Darling Downs, investigations of small-sized taxasuch as bandicoots are particularly important because theyonce occurred sympatrically with now extinct megafauna. Inthe light of the on-going controversy over the timing andcauses of Australian megafauna extinctions (Choquenot &Bowman 1998; Miller et al. 1999; Field & Fullager 2001;Roberts et al. 2001a, b; Brook & Bowman 2002) studies ofsmall-sized taxa and habitat change may elucidate causes formegafaunal decline on the Darling Downs.
The occurrence of P. nasuta in the Darling Downs fossilrecord is of little palaeoenvironmental significance becausethe species is known from a wide range of varying habitats.However, the fossil record of species that have more criticalenvironmental preferences such as I. obesulus, provides evid-ence that sclerophyllous woodlands and forests with denseunderstory vegetation were significant on the PleistoceneDarling Downs. Periodic Pleistocene fires may have createdmosaics of habitat suitable to sustain I. obesulus populationson the Darling Downs. Scrubby thicketed areas may alsohave existed to support populations of P. bougainville.
Comparison of the Darling Downs fossil bandicoot as-semblages to the geographical distribution of both mod-ern and fossil bandicoot assemblages where I. obesulus,P. bougainville and P. nasuta co-exist, suggests that theDarling Downs assemblage is unique. The geographical dis-tributions of extant populations of I. obesulus and P. nasutaoverlap in southeastern Australia and in far north Queensland(Fig. 3). Similarly, I. obesulus and P. nasuta occur sympatric-ally in Pleistocene fossil assemblages of the Texas Cavesfaunas, southeastern Queensland (Archer 1978), CathedralCave, central New South Wales (Dawson & Augee 1997) and,possibly, Cement Mills, southeastern Queensland (Bartho-lomai 1977: Fig. 3). Pre-European settlement, extant andsub-fossil populations of I. obesulus and P. bougainville over-lapped in southern South Australia and southwestern WesternAustralia (Fig. 3). Pleistocene fossil assemblages containingsympatric associations of those two species have been recor-ded from Victoria Cave and Henschke Fossil Cave, south-eastern South Australia (Smith 1972; Pledge 1990), SetonRock Shelter, Kangaroo Island (Hope et al. 1977) and Mam-moth Cave and Devil’s Lair, southwestern Western Australia(Merilees 1965; Dortch & Merrilees 1971: Fig. 3). Similarly,prior to European settlement, the geographical distributionof extant populations of P. bougainville and P. nasuta over-lapped slightly in southeastern New South Wales. On theDarling Downs, P. bougainville and P. nasuta are the onlybandicoot taxa represented at QML1396. However, thosetwo species, plus I. obesulus and P. sobbei, were collectedfrom the same stratigraphic horizon at QML796. Hence, theQML796 fossil bandicoot assemblage represents the only
fauna, fossil or modern, where I. obesulus, P. bougainvilleand P. nasuta are known to have occurred sympatrically.Although there are no modern analogues to explain such adiverse assemblage, the dynamic processes involved in theaccumulation of fossil assemblages must be fully understoodbefore palaeoenvironmental interpretations can be made. Hy-potheses to explain the accumulation of the QML796 include:(i) the Kings Creek catchment sampled a wide geographicalarea and possibly several habitats resulting in a spatiallymixed assemblage; (ii) fossil material was reworked fromolder to younger units resulting in a temporally mixed as-semblage; or (iii) a mosaic of habitats was present during thePleistocene to support more diverse bandicoot populationsthan today.
Documentation of the geographical area sampled in pa-laeoecological studies of fossil vertebrate deposits is rarelyattempted, primarily because it is commonly difficult orimpossible to determine the precise geographical extentrepresented by samples. The geographical extent of pa-laeodrainages is commonly poorly constrained, hence fossilassemblages in fluvial settings may contain geographic-ally mixed assemblages. However, the modern Kings Creekcatchment suggests a relatively small sampling area (Fig. 1).With relatively low rates of erosion and uplift since the latePleistocene, the Pleistocene Kings Creek catchment is un-likely to have been significantly larger than present and theupstream portion of the catchment is bounded to the north,east and south by the Great Dividing Range, which actsas a regional divide. Hence, it is highly unlikely that theKings Creek fossil deposits represent accumulations of ma-terial from geographical areas outside the immediate moderncatchment area. Therefore, hypothesis 1 is rejected. In addi-tion, while the bandicoot fossil assemblage is representedby disarticulated material, the lack of abrasive markings androunding of edges of bone indicate that reworking is minimal.Hence, hypothesis 2 is also rejected. The favoured hypothesisexplaining the Kings Creek bandicoot assemblages is that amosaic of suitable habitats was present in the PleistoceneKings Creek catchment.
The occurrences of non-analogue assemblages of fossiltaxa, such as the Darling Downs Pleistocene bandicoot taxa,can be interpreted to suggest that past climates were moreequable than at present and a greater range of habitat nicheswere available (Lundelius 1983, 1989; Graham & Lundelius1984). A more equable climate may be achieved when anenvironment has a lower temperature and lower evaporationrate resulting in increased moisture and that would result ina less extreme environment throughout the year (Lundelius1983). A climatic regime such as that may have operated onthe Darling Downs during the Pleistocene such that it couldsupport sympatric populations of I. obesulus, P. bougainvilleand P. nasuta.
The relationship between fossil and extant populationsof I. obesulus, P. bougainville and P. nasuta on the DarlingDowns is similar to that for certain Pleistocene faunas ofsouthern Africa, where Pleistocene deposits contain severalspecies that do not occur in those regions today, althoughthey do occur sympatrically in other parts of Africa (Klein1975). Lundelius (1989) recognised that those African fossilmammal assemblages are not ‘disharmonious’ assembl-ages in the sense that the extant species populations aretotally allopatric, but that they indicate that environmentalchange must have altered the distribution of those populationssignificantly since the Pleistocene. Significant environmental
75
Fossil Bandicoots and environmental change 355
change is also likely to be responsible for the changes inthe geographical distributions of Darling Downs bandicoots.Contraction of woodlands and scrublands and expansion ofgrasslands would probably have resulted in less suitable hab-itat for bandicoots in general. Habitat change was clearlydetrimental to I. obesulus and P. bougainville populations,resulting in the contraction of their geographical distribu-tions. The persistence of P. nasuta populations on the DarlingDowns from the Pleistocene to the present is likely to be at-tributable to that species’ ability to occupy a wide range ofhabitats.
Extinction of the megafauna during the late Pleisto-cene may also be associated with environmental changeon the Darling Downs. Whether that environmental changewas due to the effects of anthropogenic modification of thelandscape through the over-use of land management prac-tices such as burning (Jones 1969), or natural contraction ofwoodlands and scrublands through aridification during theonset of the last glacial maximum, is unknown. Burning ofthe Pleistocene Darling Downs landscape by humans couldhave indirectly created mosaics of suitable habitat to supportI. obesulus populations, but may have been detrimental tothe persistence of the megafauna. However, while there isa temporal overlap in the age of the Darling Downs fossildeposits (45–40 ka) and the arrival of the first humans inAustralia (∼ 56 ± 4 ka: Roberts et al. 1994; Thorne et al.1999), there is no evidence of humans on the Darling Downsbefore 12 ka (Gill 1978). Clearly, significant environmentalchange occurred on the Darling Downs some time during thelate Pleistocene resulting in both absolute and regional ex-tinctions of several species. Only through additional studiesof Darling Downs palaeoenvironments will hypotheses aboutenvironmental change and species extinction be further con-strained.
Acknowledgements
I thank Gregg Webb and Bernie Cooke for helpful com-ments and discussions on earlier drafts of this manuscript.Scott Hocknull and Brendan Brooke are thanked for help-ful discussions on various aspects of Darling Downs pa-laeoenvironments. Discussions with Alex Baynes stimulatedthe investigation of non-analogue faunas from the Pleisto-cene Darling Downs. Ricky Bell, Phillip Colquhon, LukeShipton, Matthew Ng, Joanne Wilkinson, Trevor Sutton andIan, Diane and Amy Sobbe provided much needed supportand assistance in the collection and preparation of fossil ma-terial. Andrew Amey provided access to modern comparativematerial in the Queensland Museum. Desmond and JenniferPrice are thanked for their continued support. AMS14C dat-ing of the study at ANSTO was supported by grants fromAINSE (Grant nos: 02/013 & 03/123). This work was fun-ded in part by both the Queensland University of Technologyand the Queensland Museum.
References
Andrews, P. 1990. Owls, caves and fossils. University of Chicago Press,Chicago, 231 pp.
Aplin, K. P. & Archer, M. 1987. Recent advances in marsupial systemat-ics with a new syncretic classification. Pp. xv–1xxii in M. Archer (ed.)Possums and Opossums: studies in evolution. Surrey, Beatty and Sonsand the Royal Zoological Society of New South Wales, Sydney.
Archer, M. 1976. Phascolarctid origins and the potential of the selen-odont molar in the evolution of diprotodont marsupials. Memoirs ofthe Queensland Museum 17: 367–371.
— 1978. Quaternary vertebrate faunas from the Texas Caves of southeast-ern Queensland. Memoirs of the Queensland Museum 19: 61–109.
Ashby, E., Lunney, D., Robertshaw, J. & Harden, R. 1990. Distributionand status of bandicoots in New South Wales. Pp. 43–50 in Seebeck,J. H., Brown, P. R., Wallis, R. L. & Kemper, C. M. (eds) Bandicootsand Bilbies. Surrey Beatty and Sons, New South Wales, 392 pp.
Bartholomai, A. 1973. The genus Protemnodon Owen (Marsupialia; Mac-ropodidae) in the upper Cainozoic deposits of Queensland. Memoirsof the Queensland Museum 16: 309–363.
— 1976. Notes on the fossiliferous Pleistocene fluviatile deposits of theeastern Darling Downs. Bureau of Mineral Resources, Geology andGeophysics, Bulletin 166: 153–154.
— 1977. The vertebrate fauna from Pleistocene deposits at Cement Mills,Gore, southeastern Queensland. Memoirs of the Queensland Museum18: 41–51.
Braithwaite, R. W. 1995. Southern brown bandicoot. Pp. 176–177 inStrahan, R. (ed.) The Mammals of Australia. New Holland Publishers,Australia, 756 pp.
Brook, B. W. & Bowman, D. M. J. S. 2002. Explaining the Pleisto-cene megafaunal extinctions: models, chronologies, and assumptions.Proceedings of the National Academy of Sciences of the United Statesof America 99: 14624–14627.
Brothwell, D. & Jones, R. 1978. The relevance of small mammal stud-ies to archaeology. Pp. 47–57 in Brothwell, D. R., Thomas, K. D. &Clutton-Brock, J. (eds) Research problems in Zooarchaeology. Occa-sional Publications no. 3. Institute of Archaeology, London.
Choquenot, D. & Bowman, D. M. J. S. 1998. Marsupial megafauna,Aborigines and the overkill hypothesis: application of predator–preymodels to the question of Pleistocene extinction in Australia. GlobalEcology and Biogeography Letters 7: 167–180.
Cuvier, G. L. C. F. D. 1817. Le regne animal distribue d’apres sonorganisation, pour servir de base a l’histoire naturelle des animauxet d’introduction a l’anatomie comparee. Volume 1. Deterville, Paris,540 pp.
Dawson, L. & Augee, M. L. 1997. The Late Quaternary sediments andfossil vertebrate fauna from Cathedral Cave, Wellington Caves, NewSouth Wales. Proceedings of the Linnean Society of New South Wales117: 51–78.
Desmarest, A. G. 1817. Nouveau Dictionnaire d’Histoire Naturelle, ap-plique aux arts, a l’agriculture, a l’economie rurale et domestique, a lamedicine, etc. Par societe de naturalistes et d’agriculteurs. NouveauEdn presqu’ entierement refondue et considerablement augmentee.Deterville Tom, Paris, vol. 16, 595 pp.
Dortch, C. E. & Merrilees, D. 1971. A salvage excavation in Devil’s Lair,Western Australia. Journal of the Royal Society of Western Australia54: 103–113.
Field, J. & Fullager, R. 2001. Archaeology and Australian megafauna.Science 294: 7.
Freedman, L. 1967a. Skull and tooth variation in the genus Perameles.Part I: Anatomical features. Records of the Australian Museum 27:147–166.
— 1967b. Skull and tooth variation in the genus Perameles. Part III: Met-rical features of P. gunni and P. bougainville. Records of the AustralianMuseum 27: 197–212.
Friend, J. A. & Burbidge, A. A. 1995. Western barred bandicoot. Pp.178–180 in Strahan, R. (ed.) The Mammals of Australia. New HollandPublishers, Australia, 756 pp.
Geoffroy, E. 1804. Memoire sur un nouveau genre de mammiferes abourse, nomme Perameles. Annales de la Musee National d’HistoireNaturelle de Paris 4: 56–64.
Gill, E. D. 1978. Geology of the late Pleistocene Talgai craniumfrom S. E. Queensland, Australia. Archaeology and Physical Anthro-pology in Oceania 13: 177–197.
Gordon, G. & Hulbert, A. J. 1989. Peramelidae. Pp. 603–624 in Walton,D. W. & Richardson, B. J. (eds) Fauna of Australia: Mammalia.Australian Government Publishing Service, Canberra, Vol. 1B.
Gordon, G., Hall, L. S. & Atherton, R. G. 1990. Status of bandicootsin Queensland. Pp. 37–42 in Seebeck, J. H., Brown, P. R., WallisR. L. & Kemper, C. M. (eds) Bandicoots and Bilbies. Surrey Beattyand Sons, New South Wales, 392 pp.
76
356 G. J. Price
Graham, R. W. & Lundelius, E. L. Jr. 1984. Coevolutionary disequi-librium and Pleistocene extinctions. Pp. 223–249 in Martin, P. S. &Klein, R. G. (eds) Quaternary Extinctions. University of Arizona Press,Tucson & London, 892 pp.
—, —, Graham, M. A., Schroeder, E. K., Toomey, R. S. III, Anderson,E. Barnosky, A. D., Burns, J. A., Churcher, C. S., Grayson, D. K.,Guthrie, R. D., Harington, C. R., Jefferson, G. T., Martin, L. D.,McDonald, H. G., Morlan, R. E., Semken, H. A. Jr., Webb, S. D.,Werdelin, L. & Wilson, M. C. 1996. Spatial response of mammals tolate Quaternary environmental fluctuations. Science 272: 1601–1606.
Gray, J. E. 1825. Outline of an attempt at the disposition of the Mammaliainto tribes and families with a list of the genera apparently appertainingto each tribe. Annals of Philosophy (New Series) 10: 337–344.
Hope, J. H., Lampert, R. J., Edmonson, E., Smith, M. J. & van Tets,G. F. 1977. The late Pleistocene faunal remains from Seton RockShelter, Kangaroo Island, South Australia. Journal of Biogeography 4:363–385.
Jones, R. 1969. Fire-stick farming. Australian Natural History 16: 224–228.
Kemper, C. 1990. Status of bandicoots in South Australia. Pp. 67–72 inSeebeck, J. H., Brown, P. R., Wallis, R. L. & Kemper, C. M. (eds)Bandicoots and Bilbies. Surrey Beatty and Sons, New South Wales,392 pp.
Kirsch, J. A. W. 1968. Prodromus of the comparative serology of Mar-supialia. Nature 217: 418–420.
Klein, R. G. 1975. Middle Stone Age man–animal relationships in SouthAfrica: evidence from Die Kelders and Klasies River Mouth. Science190: 265–267.
Lavery, H. J. & Grimes, R. J. 1974. Mammals and birds of the Inghamdistrict, north Queensland. I. Introduction and mammals. QueenslandJournal of Agricultural and Animal Sciences 31: 383–90.
Lawson, E. M., Elliot, G., Fallon, J., Fink, D., Hotchkis, M. A. C., Hua,Q., Jacobsen, G. E., Lee, P., Smith, A. M., Tuniz, C. & Zoppi, U.2000. AMS at ANTARES – the first 10 years. Nuclear Instrumentsand Methods in Physics Research Section B: Beam Interactions withMaterials and Atoms 172: 95–99.
Lundelius, E. L. Jr. 1983. Climatic implications of late Pleistocene andHolocene faunal associations in Australia. Alcheringa 7: 125–149.
— 1989. The implications of disharmonious assemblages for Pleistoceneextinctions. Journal of Archaeological Science 16: 407–417.
Luckett, W. P. 1993. An ontogenetic assessment of dental homologiesin therian mammals. Pp. 182–204 in Szalay, F. S., Novacek, M. J. &McKenna, M. C. (eds) Mammal Phylogeny, Volume 1. Springer-Verlag,New York.
Lyne, A. G. & Mort, P. A. 1981. A comparison of skull morphologyin the marsupial bandicoot genus Isoodon: its taxonomic implicationsand notes on new species, Isoodon arnhemensis. Australia Mammalogy4: 107–133.
Menkhorst, P. W. & Seebeck, J. H. 1990. Distribution and conservationstatus of bandicoots in Victoria. Pp. 51–60 in Seebeck, J. H., Brown,P. R., Wallis, R. L. & Kemper, C. M. (eds) Bandicoots and Bilbies.Surrey Beatty and Sons, New South Wales, 392 pp.
Merrilees, D. 1965. Fossil bandicoots (Marsupialia, Peramelidae) fromMammoth Cave, Western Australia, and their climatic implications.Journal of the Royal Society of Western Australia 50: 121–128.
Miller, G. H., Magee, J. W., Johnstone, B. J., Fogel, M. L., Spooner,N. A., McCulloch, M. T. & Ayliffe, L. K. 1999. Pleistocene extinc-tion of Genyornis newtoni: human impact on Australian megafauna.Science 283: 205–208.
Molnar, R. E. & Kurz, C. 1997. The distribution of Pleistocene verteb-rates on the eastern Darling Downs, based on the Queensland Museumcollections. Proceedings of the Linnean Society of New South Wales117: 107–134.
Muirhead, J. 1994. Systematics, evolution and palaeobiology of recentand fossil bandicoots (Marsupialia: Peramelemorphia). PhD thesis:University of New South Wales, Sydney, 463 pp.
—, Dawson, L. & Archer, M. 1997. Perameles bowensis, a new species ofPerameles (Peramelemorphia, Marsupialia) from the Pliocene faunasof Bow and Wellington Caves, New South Wales. Proceedings of theLinnean Society of New South Wales 117: 163–173.
Pledge, N. S. 1990. The Upper Fossil Fauna of the Henschke Fossil Cave,Naracoorte, South Australia. Memoirs of the Queensland Museum28: 247–262.
Price, G. J. 2002. Perameles sobbei, sp. nov. (Marsupialia, Peramel-idae), a Pleistocene bandicoot from the Darling Downs, south-easternQueensland. Memoirs of the Queensland Museum 48: 193–197.
— 2003. Pleistocene palaeoecology of the eastern Darling Downs: SiteQML796. Abstracts 6–7 in Conference on Australian Vertebrate Evolu-tion, Palaeontology, and Systematics, Queensland Musuem, Brisbane,July 7–11th 2003.
— & Sobbe, I. H. 2003. The palaeoecology of Frog Hollow (QML1396),King Creek, Darling Downs. Abstracts 8–9 in Conference onAustralian Vertebrate Evolution, Palaeontology, and Systematics,Queensland Museum, Brisbane, July 7–11th 2003.
Poole, W. E. 1995. Eastern grey kangaroo. Pp. 335–338 in Strahan, R.(ed.) The Mammals of Australia. New Holland Publishers, Australia,756 pp.
Quoy, J. R. C. & Gaimard, J. P. 1824. Zoologie. Pp. 56 in de Freycinet,L. C. (ed.) Voyage autour du Monde . Pillet Aine, Imprimeur-Libraire,Paris.
Roberts, R. G., Jones, R., Spooner, N. A., Head, M. J., Murray, A. S. &Smith, M. A. 1994. The human colonisation of Australia: optical datesof 53 000 and 60 000 years bracket human arrival at Deaf Adder Gorge,Northern Territory. Quaternary Science Reviews 13: 575–583.
Roberts, R. G., Flannery, T. F., Ayliffe, L. K., Yoshida, H., Olley, J. M.,Prideaux, G. J., Laslett, G. M., Baynes, A., Smith, M. A., Jones,R. & Smith, B. L. 2001a. New ages for the last Australian megafauna:continent-wide extinction about 46 000 years ago. Science 292: 1888–1892.
—, —, —, —, —, —, —, —, —, —, & — 2001b. Archaeology andAustralian megafauna: response. Science 294: 7.
Rounsevell, D. E. & Mooney, N. 1995. Thylacine. Pp. 164–165 inStrahan, R. (ed.) The Mammals of Australia, New Holland Publish-ers, Australia, 756 pp.
Semken, H. A. 1974. Micromammal distribution and migration duringthe Holocene. P. 25 in Abstracts of the 3rd Annual Meeting of theAmerican Quaternary Association.
Shaw, G. 1797. The Naturalist’s Miscellany: or coloured figures of naturalobjects, drawn and described immediately from nature, Vol. 8. E.Nodder, London, 298 pp.
Smith, M. J. 1972. Small fossil vertebrates from Victoria Cave, Nara-coorte, South Australia. II. Peramelidae, Thylacindae and Dasyuridae(Marsupialia). Transactions of the Royal Society of South Australia 96:125–137.
— 1995. Toolache wallaby. Pp. 339–340 in Strahan, R. (ed.) The Mammalsof Australia. New Holland Publishers, Australia, 756 pp.
Stafford, T. W. Jr., Semken, H. A. Jr., Graham, R. W., Klippel, W. F.,Markova, A., Smirnov, N. G. & Southon, J. 1999. First acceleratormass spectrometry 14C dates contemporaneity of non-analog speciesin late Pleistocene mammal communities. Geology 27: 903–906.
Stoddart, E. 1995. Long-nosed bandicoot. Pp. 184–185 in Strahan, R.(ed.) The Mammals of Australia, New Holland Publishers, Australia,756 pp.
Szalay, F. 1982. A new appraisal of marsupial phylogeny and classifica-tion. Pp. 621–640 in Archer, M. (ed.) Carnivorous marsupials. SurreyBeatty & Sons and Royal Zoological Society of New South Wales,Sydney.
Thorne, A., Grun, R., Mortimer, G., Spooner, N. A., Simpson, J. J.,McCulloch, M., Taylor, L. & Curnoe, D. 1999. Australia’s oldesthuman remains: age of the Lake Mungo 3 skeleton. Journal of HumanEvolution 36: 591–612.
Van Dyck, S. M. & Longmore, N. W. 1991. The mammals records.Pp. 284–336 in Ingram, G. J. & Raven, R. J. (eds.) An Atlas ofQueensland’s frogs, reptiles, birds and mammals. Board of Trusteesof the Queensland Museum, Queensland, 391 pp.
Vigne, J. & Valladas, H. 1996. Small mammal fossil assemblages asindicators of environmental change in northern Corsica during the last2500 years. Journal of Archaeological Science 23: 199–215.
Woods, J. T. 1960. Fossiliferous fluviatile and cave deposits. Journal ofthe Geological Society of Australia 7: 393–403.
77
78
Paper 2. PRICE, G.J., TYLER, M.J. & COOKE, B.N. 2005. Pleistocene frogs from
the Darling Downs, southeastern Queensland, Australia, and their
palaeonenvironmental significance. Alcheringa 29: 171-182.
Late Pleistocene Darling Downs climates and habitats are interpreted based
on fossil frog assemblages. Potential taphonomic biases are also identified.
Contribution of authors
I collected, prepared and identified most of the material that was
documented in this paper (with additional support from others noted in the
Acknowledgements). I also supervised the labouring efforts of the volunteers
who assisted in the preparation of fossil material. Additionally, I prepared the
original and final manuscript for publication.
Michael J. Tyler confirmed my original identifications of fossil material and
provided comments on a draft of the manuscript.
Bernard N. Cooke provided material from two of the four localities
mentioned in the manuscript and contributed to the discussion.
79
80
81
82
83
84
85
86
87
88
89
90
91
92
Paper 3. PRICE, G.J. & SOBBE, I.H. 2005. Pleistocene palaeoecology and
environmental change on the Darling Downs, southeastern Queensland,
Australia. Memoirs of the Queensland Museum. 51: 171-201.
This chapter presents a detailed stratigraphic, sedimentologic, taphonomic
and palaeoecologic analysis of the late Pleistocene Darling Downs fossil
deposit at site QML1396. It represents the first of my broader excavations of
the dated faunas, including the descriptions of over 40 taxa, and provides the
first palaeoecological interpretations from this study that bear on megafaunal
extinction.
Contribution of authors
I collected, prepared and identified most of the material that was examined in
this paper (including all non-megafaunal taxa, with additional support from
others noted in the Acknowledgements). I also supervised the laboring
efforts of the volunteers who assisted in the preparation of the fossil material.
I measured stratigraphic sections, collected sediment samples, and carried
out grain size analyses. I conducted all taphonomic analyses and
subsequent palaeoecologic analyses. I prepared grants for funding the
radiocarbon dating component of the study. Additionally, I prepared the
original and final manuscripts for publication.
Ian H. Sobbe assisted in the collection, preparation, identification of
megafauna taxa, and interpretation of formational processes of the deposit.
93
PLEISTOCENE PALAEOECOLOGY AND ENVIRONMENTAL CHANGE ON THEDARLING DOWNS, SOUTHEASTERN QUEENSLAND, AUSTRALIA.
GILBERT J. PRICE AND IAN H. SOBBE
Price, G.J. & Sobbe, I.H. 2005 05 31: Pleistocene palaeoecology and environmental changeon the Darling Downs, southeastern Queensland, Australia. Memoirs of the QueenslandMuseum 51(1): 171-201. Brisbane. ISSN 0079-8835.
A diverse Pleistocene fossil assemblage was recovered from a site (QML1396)exposed in the southern banks of Kings Creek, Darling Downs, southeasternQueensland. The site includes both high-energy lateral channel deposits andlow-energy vertical accretion deposits. The basal fossil-bearing unit is laterallyextensive, fines upward and its geometry and sedimentary structures suggestdeposition within a main channel. The coarse channel fill passes upward intooverbank levee deposits made up of lenticular sandy-shelly strata alternating withmuds. Several taphonomic biases relating to preservation of different faunal groupsand skeletal elements was discerned. Biases may be related to fluvial sorting of theassemblage, but causes for differences between the preservation and accumulationof mammal versus non-mammal terrestrial vertebrates remain unclear. In general,the vertebrate material was accumulated and transported into the deposit from thesurrounding proximal floodplain. The assemblage is composed of 44 speciesincluding molluscs, teleosts, anurans, chelids, squamates, and small and large-sizedmammals. Palaeoenvironmental analysis suggests that a mosaic of habitats,including vine thickets, scrublands, open sclerophyllous woodlands interspersedwith sparse grassy understories, and open grasslands, were present on thefloodplain during the late Pleistocene. From sedimentological and ecological data,it is evident that increasing aridity during the late Pleistocene led to woodland andvine thicket habitat contraction, and grassland expansion on the floodplain. Atpresent, there is no evidence to support the suggestion that the retraction of latePleistocene Darling Downs habitats was due to anthropogenic factors.�Pleistocene, Darling Downs, Kings Creek catchment, taphonomy,sedimentology, habitat change, megafauna.
Gilbert J. Price, Queensland University of Technology, School of Natural ResourceScience, GPO Box 2434, Brisbane, 4001, Australia. Ian. H. Sobbe, M/S 422,Clifton, 4361, Australia. 1 August 2004.
The Darling Downs, southeastern Queensland,contains some of the most extensive andsignificant Pleistocene megafauna deposits inAustralia. Molnar & Kurz (1997) recognisedmore than 50 specific Darling Downs localitieswhere fossil material has been collected. Specieslists are dominated by large-sized taxa such asDiprotodon spp. , Macropus t i tan , andProtemnodon spp. (Bartholomai, 1976; Molnar& Kurz, 1997). More recently, Roberts et al.(2001a) suggested that some Darling Downsfossil deposits are among the youngest depositsknown to contain megafauna remains. AsPleistocene fossils have been known from theDarling Downs since the 1840’s (Owen, 1877a),i t is general ly assumed that thepalaeoenvironmental record is well established.Darling Downs palaeoenvironments have beeninterpreted as consisting of vast grasslands andwoodlands, as indicated by an abundant and
diverse range of grazing and browsingmegafauna species preserved in the deposits(Bartholomai, 1973; 1976; Archer, 1978; Molnar& Kurz, 1997). However, Molnar & Kurz (1997)recognised a collecting bias towards large-sizedspecies suggested that smaller-sized taxa havegenerally been overlooked. Additionally, therehave been few attempts to documentsedimentologic and stratigraphic aspects of thePleistocene deposits of the region. Macintosh(1967), Gill (1978), and Sobbe (1990) providedlimited stratigraphies for sections along creeksfrom the southern Darling Downs, introducingthe terms ‘Toolburra silt’, ‘Talgai pedoderm’ and‘Ellinthorpe clay’. However, those names havenot seen subsequent use and are not consideredvalid stratigraphic units (Molnar & Kurz, 1997).Taphonomic aspects of the deposits are alsolargely unknown. Molnar et al. (1999) reported adeposit that contained articulated remains of
94
megafauna taxa, but noted that articulation offossil skeletal material was relatively uncommonin the region. Collectively, palaeonvironmentalinterpretations of the region are limited owing tothe poor understanding of stratigraphic,sedimentologic and taphonomic aspects of thedeposits, as well as past collecting biases thathave focused on the recovery of large-sized taxa.
Recent systematic collecting of a deposit (siteQML1396) from the Darling Downs targeted therecovery of both large and small-sized taxa.Consequently, a comprehensive faunalassemblage has been uncovered. Typical DarlingDowns megafauna taxa are represented, as wellas an extensive small-sized fauna that includes adiverse range of molluscs, teleosts, anurans,chelids, squamates, and small and large-sizedmammals. Such assemblages are beginning todemonstrate that Pleistocene Darling Downspalaeoenvironments were much more complexthan previously thought (Price, 2002; Price,2004; Price et al., in press). The aim of the presentpaper is to describe a multidisciplinary approachintegrating sedimentologic and taphonomicinformation, as well as ecological informationobtained from mammals and non-mammals thatoccur in the deposit. The combined data sets
allow a better understanding of Pleistocenepalaeoenvironments and possible climate changein the region. In light of the ongoing debate overthe causes and timing of Australian megafaunaPleistocene extinctions (e.g. Field & Fullager,2001; Roberts et al. 2001a, b; Brook & Bowman,2002; 2004; Barnosky et al., 2004; Johnson &Prideaux, 2004; Wroe, 2004), studies ofPleistocene palaeoenvironments may provideimportant information that could aid inelucidating the causes of faunal change.
SETTING
The Darling Downs, southeastern Queensland,encompasses low rolling hills and plains west ofthe Great Dividing Range. Fluvial sediments ofthe region consist of clays, silts and sands that aregenerally derived from the erosion of Mesozoicsandstones (Gill, 1978) and Miocene basalts ofthe Great Dividing Range (Woods, 1966). SiteQML1396 is exposed laterally over 70 metres inthe southern bank of Kings Creek, southernDarling Downs (Fig. 1). The modern KingsCreek catchment, bounded to the north, east andsouth by the Great Dividing Range, is fed byseveral mainly dry or intermittent watercourses(Fig. 1), resulting in a relatively small geographic
172 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 1. Modern Kings Creek Catchment with heights (metres) of surrounding peaks, and the current study area,QML1396 (GDR: Great Dividing Range; KCC: Kings Creek Catchment).
95
sampling area. Considering relatively low ratesof erosion and uplift since the late Pleistocene, itis unlikely that the Pleistocene Kings Creekcatchment was markedly larger than present(Price, 2004). Therefore, it is unlikely thatmaterial from QML1396 was subjected to longdistance fluvial transport from a significantlylarger catchment.
METHODS
SEDIMENTOLOGY. A section was measuredrepresenting the entire depositional sequenceexposed in the creek bank. Stratigraphic horizonswere distinguished on the basis of lithologicalcriteria. Sediment samples were collected fromeach stratigraphic horizon for the purpose ofgrain size analysis. The sediment samples weredisaggregated by applying alternating cycles ofbleach and detergent. Disaggregated sedimentswere dried and sieved according to Wentworthsize classes (-2 to +4 phi; Wentworth, 1922).Differentiation and identification of calcretefollowed Arakel (1982).
One unit (Horizon D; Fig. 2) containedabundant lenses of the freshwater gastropod,Thiara (Plot iopsis) balonnensis . Theorientations of 100 gastropods from one suchlense were measured to determine whetherfluvial transport acted on the gastropods ininfluencing their final orientations. The anglewas measured between north and the spire of theshell (long direction).
TAPHONOMY. Cranial and post-cranialelements from horizons B and D formed the basisfor the taphonomic study. The units of elementrepresentation were NISP (number of identifiedspecimens), MNI (minimum number ofindividuals- as determined by counting the mostabundant element referable to a particular speciesrepresented in the sample), and MNE (minimumnumber of elements) (following Andrews, 1990).For vertebrates, calculation of MNI was based onmaxillary and dentary remains, except in the caseof fish, frogs, turtles and some squamates wherevertebrae, pelvi, shell fragments and osteodermswere used respectively.
Several indices were used to characterise anddescribe the taphonomic features of theassemblage based on the skeletal remains of largeand small mammals, as well as squamates.Relative abundance. Relative abundance of eachskeletal element was calculated following theequation:
Ri= Ni � 100 / (MNI)Ei (1)
following Andrews (1990), where R = relativeabundance of element i, n= minimum number ofelement i, MNI = minimum number ofindividuals, and E = expected number of elementi in the skeleton. The relative abundance equationallows the comparison of different skeletalelements that occur in varied proportions inmammal or squamate skeletons. Determinationof E was based on modern comparative skeletonsfor mammals and follows Greer (1989) forsquamates.
% Post-crania to crania. The percentage ofpost-crania to crania follows Andrews (1990).The number of post cranial elements (femur,tibia, humerus, radius and ulna [n=10]) arecompared to cranial elements (dentary, maxillaand molars [n=16 for murids, 20 for marsupials, 4for squamates]). As the ratio of post crania tocrania is not 1:1, the post crania and crania arecorrected by 10/16 for murids, 10/20 formarsupials, and 10/4 for squamates, to matchnumbers of skeletal elements.
DARLING DOWNS PALAEOECOLOGY 173
FIG. 2. Measured section of QML1396.
96
% Distal element loss. Distalelement loss was measured bycomparing the number of distallimbs (tibia and radii) to proximallimbs (femura and humeri). Theratio measures preferential loss ofdistal limbs.% Fore limb element loss. Limbelement loss was measured bycomparing the number of fore limbbones (humeri and radii) to hindlimb bones (femora and tibiae).The rat io measures anypreferential loss of fore limbs.% Molar tooth loss. Molar toothloss was measured by comparingthe number of isolated molars inthe sample to the number ofavailable alveoli spaces in thedentaries or maxillae. Values>100% indicates the loss ordestruct ion of dentar ies ormaxillae (Andrews, 1990).% Relative loss of molar tooth sites. Relative lossof molar tooth sites was calculated by comparingthe actual number of tooth sites in the sample(regardless of whether they contain teeth or not)to the theoretical number of molar tooth sitesassuming that there was no breakage. Relativeloss of molar tooth sites was used as anindependent check for cranial breakage (Kos,2003).Cranial modifications. The cranial breakagepatterns of squamates and mammals wereidentified within the deposit following Andrews(1990; Figs 3 & 4). The percentage ofrepresentation of each pattern was calculated toattempt to distinguish any differences betweenlarge and small-sized mammals, as well asbetween agamid and scincid lizards.Breakage of post-crania. Identification ofbreakage patterns of major post-cranial limbbones (humeri, femora, ulnae and tibiae) followsAndrews (1990). Broken limb bones were scoredas to whether the represented proximal, shaft, ordistal portions.Comparison to “Voorhies Groups”. Theexperimental work of Voorhies (1969) andDodson (1973), on hydraulic dispersivemechanisms for mammal bones, forms acomparative framework for explaining thedispersal of skeletal elements in the fossil record.Their studies documented transportability ofdifferent skeletal elements at constant rates of
water flow, and concluded that different skeletalelements disperse at different rates in relation tostream flow velocity. Differences in the dispersalpotential of skeletal elements reflect the densityand shape of the elements. Relative abundance ofelements from the QML1396 assemblage werecompared to the published results for skeletalelement transportability in hydraulic systems.
FAUNA. Fossils were recovered by in situcollecting and sieving of sediment specifically totarget smaller specimens. Fossil material wasgenerally restricted to Horizons B and D (Fig. 2).All fossil material collected was labeledaccording to the stratigraphic horizon where itwas collected. Sediments were washed usinggraded sieves of 10mm to 1mm. Approximately700kgs of sediment were processed fromHorizon D, and 200kgs of sediment wereprocessed from Horizon B. The disparity incollecting efforts between Horizons D and Breflects the position of Horizon B below thepresent water table. Collecting of Horizon B wasgenerally possible only during droughtconditions. Most material was collected fromHorizon B in November and December 2002.
Descriptions of the fossil fauna have beenlimited to diagnostic features in most cases.Molluscan shell terminology follows Smith andKershaw (1979). Squamate cranial morphologyterminology follows Withers and O’Shea (1993).Marsupial dental nomenclature follows Luckett(1993), where the adult unreduced cheek tooth
174 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 3. Mammal cranial breakage categories from the QML1396assemblage (shaded areas indicates the preserved portions). Refer totable 5 for definition of the breakage categories.
97
formula is P1-3 and M1-4 in both upper andlower dentitions. Marsupial dental morphologyfollows Archer (1976). Higher systematicsfollows Beesley et al. (1998) for molluscs,Glasby et al. (1993) for amphibians and reptiles,and Aplin and Archer (1987) for mammals. Allmaterial is deposited at the Queensland Museum(QMF: Queensland Museum Fossil; QML:Queensland Museum Locality).
DATING. Samples of charcoal and freshwaterbivalves (Velesunio ambiguus) were submitted toANSTO (Australia Nuclear Science andTechnology Organisation; Lawson et al., 2000)for the purpose of AMS14C dating. Onlycomplete, conjoined bivalves were submitted fordating. Con-joined, apparently well-preservedbivalves are unlikely to have been reworked incomparison to disarticulated or fragmentary shellremains.
RESULTS
SEDIMENTOLOGY. The entire deposit ischaracterised by a fining-upwards sequence (Fig.2). The section is comprised of: 1) grey-white toblack clays; 2) in-situ mottled calcretes; 3) ironnodules; 4) quartz sand in channel fills; 5) basalt,calcrete and sandstone pebbles and cobbles (pre-dominantly in coarser fills); and 6) invertebrateand vertebrate fossils (Table 1). Freshwaterbivalves (Velesunio ambiguus and Corbicula(Corbiculina) australis) and thiarid gastropods(Thiaria (Plotiopsis) balonnensis) are moreabundant in coarser-grained horizons such asHorizon B and D, than fine-grained horizons.Vertebrate fossil material is generally restrictedto Horizons B and D.
Horizon B exhibits the largest grain sizes (Fig.2, Table 1). The horizon is laterally extensive,being recorded over approximately 70 metres.The majority of the lower portion of Horizon B is
DARLING DOWNS PALAEOECOLOGY 175
Horizon(height)
Fill type Mean � Characteristics Notes
A (0-0.2m) Fine montmorilloniteclay 2.65 crudely horizontal bedding; poorly
sorted, srtrongly fine skewed grainspebbles to 20mm rare; shelly marterialrare; vertebrate material rare
B(0.2-0.6m) coarse grain fill bed -0.78-0.19 fining upwards sequence; poorly sorted;finely skewed grains
Freshwater molluscs abundant;vertebrate material abundant; roundedbasalt, calcrete and sandstone pebblesand cobbles abundant
C(0.6-1.7m) brown-grey clay 1.7crudely horizontal bedding, poorly tovery poorly sorted; strongly finelyskewed grains
Mollusc shell rare; vertebrate materialrare
D (1.7-2.6m) coarse to fine-sizedquartz sand beds 0.6-2.0
Sand beds 3cm to 10cm thick overlainby laterally discontinuous horizontaland sloping shelly lenses 2-10cm thick;shell beds with desiccation cracks, infilled by fine clays; very poorly sorted,fine skewed grains
Freshwater gastropods and small bi-valves common, large-sized bivalvesrare; polymodal orientation of Thiara(Plotiopsis) balonnensis gastropods(Fig. 5); vertebrate material abundant;shell and vertebrate fossil material com-monly cemented by calcrete
E (2.6-3.1m) brown clay 2.53 Crudely horizontal bedding; poorlysorted, strongly fine skewed grains
Mollusc shell rare; vertebrate materialrare
F (3.1-7.2m) brown clay 1.88
Crudely horizontal bedding; in-situ,mottled, grey-white calcrete; ironnodules to 5mm diameter present;poorly sorted, strongly fine skewedgrains
Mollusc shell rare; vertebrate materialrare
G (7.2-7.7m) black clay 2.0Crudely horizontal bedding; iron oxidesto 5mm diameter present; poorly sorted,strongly fine skewed grains
Organic rich clay; mollusc shell rare;vertebrate material rare
H (7.7-8.3m) grey-white clay 2.8 Crudely horizontal bedding; poorlysorted, strongly fine skewed grains
Mollusc shell rare; vertebrate materialrare
I (8.3-8.8mm) grey-white clay 3.0Crudely horizontal bedding; iron oxidesto 5mm diameter present; poorly sorted,strongly fine skewed grains
Mollusc shell rare; vertebrate materialrare
J (8.8-9.5m) grey clay 2.4 Crudely horizontal bedding; poorlysorted, strongly fine skewed grains
Mollusc shell rare; vertebrate materialrare
K (9.5-10.2m) black clay 2.98 Moderately sorted, strongly fine skewedgrains
Organic rich, likely altered by modernagriculture
TABLE 1. Description of stratigraphic horizons at QML1396.
98
below the modern watertable. Large-sizedbivalves (Velesunio ambiguus) are moreabundant in Horizon B than in Horizon D.
Horizon D is represented by a series of coarseto fine quartz sand beds that are overlain bylaterally discontinuous horizontal and slopingshelly lenses (Fig. 2, Table 1). Desiccation crackswithin the shelly lenses are filled with fine clay. Arose diagram plot of the orientations offreshwater gastropods (Thiaria (Plotiopsis)balonnensis) indicates a polymodal distribution(Fig. 5).
In-situ, non-reworked mottled calcretes occurin Horizon F. Iron oxide nodules were alsopresent within that horizon, as well as Horizons Gand I. Few sedimentary structures other thancrudely horizontal bedding were observed withinother stratigraphic horizons (Fig. 2, Table 1).
TAPHONOMY. Vertebrate fossil material wasgenerally restricted to Horizons B and D. Fossilmaterial from other horizons is poorly preserved.Hence, the following taphonomic observationsare based on fossil material from Horizons B andD. Additionally, a large number of unidentifiablebone fragments were collected from the mainfossiliferous horizons. Few meaningful datacould be obtained from those fragments, hence,the taphonomic component was based solely onidentifiable elements.
176 MEMOIRS OF THE QUEENSLAND MUSEUM
Horizon D Horizon B
Species NISP MNI NISP MNI
Velesunio ambiguus 10+ 5+ 20+ 10+
Corbicula (Cobiculina) australis 100+ 100+ 50+ 50+
Thiara (Plotiopsis) balonnensis 1000+ 1000+ 50+ 50+
Gyraulus gilberti* 249 249 0 0
Coencharopa sp.* 9 9 0 0
Gyrocochlea sp. 1* 35 35 0 0
Gyrocochlea sp. 2* 5 5 0 0
Austrocuccinea sp.* 1 1 0 0
Xanthomelon pachystylum* 1 1 0 0
Strangesta sp.* 1 1 0 0
Saladelos sp.* 1 1 0 0
Teleost 89 1 0 0
Limnodynastes tasmaniensis 8 8 0 0
L. sp. cf. L. dumerili 3 3 0 0
?Limnodynastes 1 1 0 0
Neobatrachus sudelli 2 2 0 0
Kyarranus sp.* 1 1 0 0
chelid 4 1 0 0
Tympanocryptis “lineata”* 15 4 0 0
"Sphenomorphus group” sp. 1 19 13 0 0
“Sphenomorphus group” sp. 2 6 2 0 0
Tiliqua rugosa* 6 1 0 0
Cyclodomorphus sp.* 1 1 0 0
Varanus sp. 1 1 0 0
Megalania prisca** 4 1 0 0
elapid 14 1 0 0
Sminthopsis sp. 1 1 0 0
Dasyurus sp. 1 1 0 0
Sarcophilus sp.* 0 0 1 1
Thylacinus cynocephalus** 0 0 1 1
Perameles bougainville* 1 1 0 0
Pe. nasuta 1 1 0 0
Diprotodon sp.** 0 0 1 1
Thylacoleo carnifex** 0 0 1 1
Aepyprymnus sp. 1 1 0 0
Troposodon minor** 0 0 2 2
Macropus agilis siva** 5 2 1 1
M. titan** 1 1 5 2
Protemnodon anak** 2 1 3 1
Pr. brehus** 2 1 1 1
Pseudomys sp.* 4 2 0 0
Rattus sp. 2 1 0 0
unidentified murid 182 26 0 0
TABLE 2. Species NISP and MNI for Horizons D andB at QML1396 (* Extinct on Darling Downs; **Totally extinct).
Horizon D Horizon B
<5kgmammals
<5kgsquamates
>5kgmammals
>5kgmammals
skeletalelement n % n % n % n %
dentary 7 10.6 29 72.5 1 8.3 6 30
maxilla 7 10.6 17 42.5 4 33.3 0 0
incisor 101 76.5 na na 2 8.3 4 20
molar 97 19 na na 23 24 19 11.9
femur 11 16.7 0 0 0 0 0 0
tibia 18 27.3 0 0 0 0 0 0
pelvis 2 3 0 0 1 8.3 0 0
calcaneum 10 15.2 0 0 1 8.3 0 0
humerus 4 6.1 2 5 0 0 0 0
radius 2 3 0 0 0 0 0 0
ulna 8 12.1 0 0 0 0 0 0
ribs 6 0.9 0 0 0 0 0 0
vertebra 57 3.9 196 12.6 20 7.6 0 0
phalange 53 3.5 2 0.2 1 0.4 2 0.4
TABLE 3. MNE and expected relative abundance ofskeltal elements recovered from Horizons D & B atQML1396.
99
Species representation. In terms of diversity, landsnails, frogs, squamates and small mammalsdominated the terrestrial faunal componentrepresented in the Horizon D assemblage (Fig. 6,Table 2). Large mammals were the leastrepresented size group in Horizon D, and the onlyrepresented terrestrial group in Horizon B (Fig.6).
Skeletal relative abundance. Skeletal relativeabundance was calculated for large and smallmammals, as well as squamates (Table 3). Interms of relative abundance, cranial elements ofsquamates are the most well represented elementfor the three major groups of terrestrial animals inHorizon D. However, overall, the relativeabundance of all skeletal elements suggests thatthey are underrepresented. Incisors are the mostabundant cranial element recovered for smallmammals in Horizon D, but that may reflect aprocessing bias as incisors are among the mosteasily identifiable small mammal remains(Andrews, 1990). The dentary is a relativelyrobust element and that may account for thehigher proportion of skeletal elements forsquamates and mammals in both horizons. Thereis a greater loss of squamate post-cranial remainsin comparison to mammals in Horizon D.
Small-s ized terrestr ia lver tebrates were notrecovered from Horizon B.Skeletal modif icat ions.Indices of skeletal mod-ifications (Table 4) indicatethat there is significant loss ofpost-cranial elements in eachhorizon. Horizon B iscompletely devoid of large-sized mammal limb boneelements. For Horizon Dmammals there was a slightloss of proximal l imbs(femora and humeri) incomparison to distal limbs(tibiae and radii). Additionally,there was a significant loss offorelimb elements in com-parison to hind limbs. Reasonsfor the loss of different limbelements remain unclear, butmay simply be the result ofusing stat is t ical ly smallnumbers for comparison.Indices for the loss of molarteeth and molar tooth sitesindicate the loss or destruction
of dentaries or maxillae for mammals within eachmain fossiliferous horizons (Table 4).Breakage of crania. There were no completemammal skulls or dentaries recovered from thedeposit (Table 5). Mammal dentary breakageappears slightly greater for Horizon D thanHorizon B. A high proportion of broken maxillaeretained only a small portion of the zygomaticarch in Horizon D.
DARLING DOWNS PALAEOECOLOGY 177
FIG. 4. Squamate cranial breakage categories from the QML1396assemblage (shaded areas indicates the preserved portions). Refer to table 6for definition of the breakage categories.
skeletalmodification
Horizon D Horizon B
<5kgmammals
< 5kgsquamates
>5kgmammals
>5kgmammals
% post-craniato crania 24.2 17 0 0
% distalelement loss 133.3 0 0 0
% fore limbloss 41.4 0 0 0
% molartooth loss 741 na
noavailable
toothspaces
150
% relativeloss of molartooth sites
275 na 160 109
TABLE 4. Skeletal modifications for arbitary faunalgroups from QML1396
100
There also were no complete squamate skullsor dentaries preserved (Table 6). Reasonablycomplete dentaries are equally abundant in bothagamids and scincids. However, particularbreakage patterns appear to be exclusive to eachsquamate family (Table 6). For agamids, thecentral portion of the dentary and central toanterior portions of the maxilla are preserved; forskinks, the majority of the dentary and central toposterior portions of the maxilla are preserved.Overall, scincid dentaries are more completelypreserved than those of agamids. However, areverse trend exists for the maxillae, where agreater portion are preserved inagamids than scincids (Table 6).
Breakage of post crania. Therewere no complete major limbbones (i.e. humeri, ulnae, femora,tibiae) preserved in the deposit(Table 7). Additionally, majorlimb bones were mostly restrictedto small-sized mammals fromHorizon D. Most broken limbbones have transverse fracturesperpendicular to the bone surfaceand indicate post-mortemfracturing of dry or fossilised bone(Johnston, 1985). Additionally,the broken ends of the limb bonesdo not appear to be significantly
rounded or abraded, suggesting minimalreworking or transport of fossil material.Squamates were represented by only twoproximal humeri from Horizon D. However, highnumbers of unidentifiable limb element shaftsfrom small-sized animals (n~120) could equallybe referable to either squamates or mammalpost-cranial limb bones.Comparison to “Voorhies Groups”. For HorizonD small-sized mammals, the majority of theskeletal elements comprise those that woulddisperse in the middle to late categories ofdispersal (Table 8). Additionally, the highnumber of limb bone shafts (see earlierdiscussion) would presumably fit within thatcategory of stream transportability. There was noclear trend for small-sized squamates from
178 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 6. Comparison of MNI and NISPof terrestrial taxa from Horizons Band D at QML1396.
Breakage patternHorizon D Horizon B
<5kgmammals
> 5kgmammals
<5kgmammals
% dentary with ascendingramus mostly absent (Fig.3A)
0 - 17
% dentary with ascendingand anterior ramus mostlyabsent (Fig. 3B)
33 - 50
% dentary with anteriorramus only, lacking inferiorborder(Fig. 3C)
67 - 0
% dentray with horizontalramus only lacking inferiorborder (Fig. 3D)
0 - 33
% maxilla with most ofzygomatic missing (Fig. 3E) 100 75 -
% maxilla alveoli or toothrow only (Fig. 3F) 0 25 -
TABLE 5. Mammal cranial modifications fromQML1396 (following breakage patterns Fig. 3)
FIG. 5. Orientations of Thiara (Plotiopsis) balonnensisgastropods (n: 100) from a single shelly lense withinHorizon D at QML1396.
101
Horizon D. For large-sized mammals fromHorizon D, the majority of elements comprisedthose that are progressively the last to betransported in flowing water. Horizon B isdominated by middle-late transported elements(i.e. dentaries; Table 8).
SYSTEMATIC PALAEONTOLOGY
A much abbreviated treatment of thesystematic palaeontology is given in order todocument the specific material for which taxa areassigned. The fundamental purpose of thetaxonomic work was to facilitate ecologic andassemblage information. Thus, only thediagnostic features of the material are provided,as all faunal elements are well known fossil orextant taxa. At the end of each description theprimary authority used for identification is givenin closed brackets. Two other publications dealwith the amphibians (Price et al., in press) and thebandicoots (Price, 2004).
Phylum MOLLUSCA Linnaeus, 1758Class BIVALVIA Linnaeus, 1758
Family HYRIIDAE Ortmann, 1910
Velesunio Iredale 1934Velesunio ambiguus (Philippi, 1847) (Fig. 7A)
REFERRED MATERIAL. QMF44633; QMF44651;QMF44653.
DESCRIPTION. Equivalved, length to 110mm,moderately to well inflated; shell thin to verythick; weak ridge runs posteriorly from umbone;pallial line well developed; pallial sinus absent;anterior and posterior adductor muscle scars well
developed; teeth lamellar, cardinal teeth absent;hinge moderately developed; beak cavitymoderately developed. [Lamprell & Healy,1998]
Family CORBICULIDAE Gray, 1847
Corbicula Mühfeld, 1811Corbicula (Corbiculina) Dall, 1903
Corbicula (Corbiculina) australis (Deshayes,1830)
(Fig. 7B)
REFERRED MATERIAL. QMF44628-30.
DESCRIPTION. Equivalved, length to 20mm,slightly inflated; pallial line entire but weak;anterior and posterior adductor muscle scarsweakly defined; anterior and posterior pedalretractor muscle scars hidden by overhang ofanterior and posterior teeth respectively; threecardinal teeth, and anterior and posterior lateralteeth well developed; beak cavity very deep;hinge line narrow. [Lamprell & Healy, 1998]
DARLING DOWNS PALAEOECOLOGY 179
<5kg mammals <5kg squamates
Limb bone n % n %
humerus
complete 0 0 0 0
proximal 1 17 2 100
shaft 4 66 0 0
distal 1 17 0 0
femur
complete 0 0 0 0
proximal 7 39 0 0
shaft 0 0 0 0
distal 11 61 0 0
ulna
complete 0 0 0 0
proximal 8 73 0 0
shaft 2 18 0 0
distal 1 9 0 0
tibia
complete 0 0 0 0
proximal 0 0 0 0
shaft 3 15 0 0
distal 18 85 0 0
TABLE 7. Breakage patterns of major post craniallimb bones from Horizon D, QML1396.
Breakage pattern agamids skinkids
% dentary mostly complete (Fig. 4A) 38 43
% posterior portion of dentary only (Fig. 4B) 0 33
% anterior portion of dentary only (Fig. 4C) 0 24
% central portion of dentary only (Fig. 4D) 38 0
% central portion of dentary only, lackinginferior border (Fig. 4E) 25 0
% premaxilla and maxilla mostly complete(Fig. 4F) 22 0
% maxilla mostly complete, lackingpremaxilla (Fig. 4G) 67 0
% premaxilla only (Fig. 4H) 11 0
% posterior portion of maxilla only(Fig. 4I) 0 25
% central portion of maxilla only (Fig. 4J) 0 75
TABLE 6. Squamate cranial modifications fromHorzon D, QML1396
102
Class GASTROPODA Cuvier, 1797Order SORBEOCONCHA Fischer, 1884
Family THIARIDAE Troschel, 1857
Thiara (Plotiopsis) Brot 1874Thiara (Plotiopsis) balonnensis
(Conrad, 1850)(Fig. 7C)
REFERRED MATERIAL. QMF44631-32.
DESCRIPTION. Shell. Elongate, dextrallycoiled, robust, turreted, length to 30mm; 6-7whorls, carinate, spiral ridges complementedwith nodules; ovoid shaped aperture; inner lipthickened, outer lip thin. [Smith and Kershaw1979]
Order PULMONATA Cuvier, 1817Family PLANORBIDAE Rafinesque, 1815
Gyraulus Charpentier,1837Gyraulus gilberti (Dunker, 1848)
(Fig. 7D).
REFERRED MATERIAL. QMF44574-79.
DESCRIPTION. Shell. Planispiral, diameter to6.29mm; 4 whorls; spire sunken; umbilicus wide;last whorl with a peripheral keel; shell sculptureconsists of fine transverse ridges; aperture keeledelongate; outer lip relatively thin and straight.[Brown, 1981]
Family RHYTIDIDAE Pilsbry, 1895
Saladelos Iredale, 1933Saladelos sp.
(Fig. 7E)
REFERRED MATERIAL. QMF44956.
DESCRIPTION. Shell planispiral, diameter to3mm; whorl count reduced, 2-3 whorls, lastwhorl capacious; spire slightly depressed; shellsculpture of fine radial ribs; umbilicus narrow;aperture ovate-lunate; lip simple. [Iredale ,1933]
Strangesta Iredale, 1933Strangesta sp.
(Fig. 7F)
REFERRED MATERIAL. QMF44582-83.
DESCRIPTION. Shell. Planispiral, diameter to6.82mm; 3-4 whorls; slightly depressed spire;apical sculpture of fine to medium coiled radialribs; umbilicus narrow; aperture wide,ovate- lunate; l ip simple. [Smith andKershaw,1979]
Family CHAROPIDAE Hutton, 1884.
Coenocharopa Stanisic, 1990Coenocharopa sp.
(Fig. 7G)
REFERRED MATERIAL. QMF44584-89.
DESCRIPTION. Shell. Planispiral, diameter to4.5mm; whorls coiled, last descending; apex andspire slightly elevated; apical sculpture ofprominent coiled radial ribs; post-nuclear
180 MEMOIRS OF THE QUEENSLAND MUSEUM
Relativemovement
Dodson (1973)small mammals
Voorhies (1969)large mammals
Horizon D Horizon B
<5kg mammals < 5kg squamates >5kg mammals >5kg mammals
late mandible skull,maxilla
tibiafemur,
calcania,ulna,
dentarymaxilla
humerus,vertebrae
radius
dentary,maxilla,vertebaehumerus
maxilladentarypelvi
vertebrae
dentary
middle-latecalcania,radius,ulna
mandible
middle
skulltibia-fibula,
femur,hunerus
femur,tibia
humeruspelvisradius
early-middlepelvis,
cervical and caudalvert.
ulna
early thoracic vertmaxilla vertebra
TABLE 8. Skeletal element transportability for small mammals (Dodson, 1973) and large mammals (Voorhies,1969) compared to the relative abundance of skeletal elements from Horizons B and D at QML1396 (listed indecreasing abundance). Elements higher in the Dodson (1973) and Voorhies (1969) columns were the last to betransported by moving water in flume experiments.
103
sculpture moderately spaced; umbilicus wide andU-shaped; aperture ovate-lunate; lip simple.[Stanisic, 1990]
Gyrocochlea Hedley, 1924Gyrocochlea sp. 1 and 2
(Fig. 7H)REFERRED MATERIAL. Sp. 1: QMF44590-95; Sp. 2:QMF44598-602.
DESCRIPTION. Shell planispiral, diameter to4mm; moderately tightly coiled whorls, lastdescending more rapidly; apex slightly concave;apical sculpture of fine crowded spiral cords andweakly curved radial ribs; umbilicus wide andU-shaped; aperture ovately lunate; lip simple.[Stanisic 1990]
REMARKS. Gyrococlea sp. 1 differs fromGyrococlea sp. 2 by a smoother shell sculpture,and possessing a more closed umbilicus.
Family SUCCINEIDAE Beck, 1837
Austrosuccinea Iredale, 1937Austrosuccinea sp.
(Fig. 7I)REFERRED MATERIAL. QMF44580.
DESCRIPTION. Shell elongate, dextrallycoiled; shell height 10.65mm; 4 whorls present,last whorl large; spire short; fine growth lines on
shell; aperture ovate; inner lip relatively straight,outer lip thin and straight. [Smith & Kershaw,1979]
Family CAMAENIDAE Pilsbry, 1895
Xanthomelon Martens, 1861Xanthomelon pachystylum (Pfeiffer, 1845)
(Fig. 7J)REFERRED MATERIAL. QMF44581.
DESCRIPTION. Shell subglobose, diameter to18.7mm; 4 whorls present, body whorl large;spire slightly elevated; shell sculpture relativelysmooth; anomphalous; aperture ovate lunate;outer and inner lip simple, thin. [Solem,1979]
Phylum CHORDATA Linnaeus, 1758Class REPTILIA Laurenti, 1768Order SQUAMATA Oppel, 1811
Family AGAMIDAE Hardwicke & Gray, 1827.
Tympanocryptis Peters, 1863Tympanocryptis “lineata” Peters, 1863
(Fig. 8H)REFERRED MATERIAL. QMF44198-202, maxillaryfragments; QMF44619, dentary.
DESCRIPTION. Maxilla. 4 foramen present;pleurodont teeth 2, acrodont teeth 12; 1stpleurodont tooth oritentated mesiobuccally; 2ndpleurodont tooth caniniform; maxillary suture
DARLING DOWNS PALAEOECOLOGY 181
FIG. 7. A. Velesunio ambiguus; B. Corbicula (Corbiculina) australis; C. Thiara (Plotiopsis) balonnensis ; D.Gyraulus gilberti; E. Saladelos sp.; F. Strangesta sp.; G. Coenocharopa sp.; H. Gyrococlea sp.; I.Austrosuccinea sp.; J. Xanthomelon pachystylum.
104
anterodorsal to pleurodont teeth; dorsalmaxillary process narrow.
Dentary. Short; 3 mental foramina present;pleurodont teeth 2, acrodont teeth 12; pleurodontteeth closely positioned, 2nd pleurodont twicethe size of the 1st; acrodont teeth sub-triangularwith indistinct anterior and posterior conids;Meckel’s groove parallel to dental sulcus,narrowed anteriorly. [Hocknull, 2002]
REMARKS. Tympanocryptis l ineata isdistinguished from other members of the genusby a combination of features including: 1) its
larger size, 2) 1st pleurodont tooth orientatedmesiolabially, and 3) lower anterior hook.
Family SCINCIDAE Oppel, 1811
Skinks are the largest and most diversesquamate group in Australia (Greer, 1979;Hutchinson, 1993). Within the Scincidae, threedistinct monophyletic groups are informallyrecognised: the Egernia group, Eugongylusgroup, and Sphenomorphus group (Greer, 1979,Hutchinson, 1993). Members allied to theSphenomorphous Group and Egernia group arerepresented in the deposit.
182 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 8. A. Fish vertebra; B. Limnodynastes tasmaniensis, left ilium; C. L. sp. cf. L. dumerili, left ilium; D.?Limnodynastes sp., right ilium; E. Neobatrachus sudelli, right ilium; F. Kyarranus sp.; G. Chelid plastronfragment; H. Tympanocryptis “lineata”, right dentary. I. “Sphenomorphus Group” sp., right dentary; J. Tiliquarugosa, osteoderm; K. Cyclodomorphus sp., left dentary; L. Varanus sp. vertebra; M. Megalania prisca,osteoderms; N. Elapid vertebra.
105
“Sphenomorphus Group” sp. 1 and 2 (sensuGreer, 1979)
(Fig. 8I)REFERRED MATERIAL. Sp. 1: QMF44620-22,QMF44654, dentaries; Sp. 2: QMF44623-25, maxillae.
DESCRIPTION. Dentary. Tooth row bears up to17 teeth or tooth loci; Meckel’s groove widelyopen along ventrolingual margin; internalseptum poorly developed; up to 6 mentalforamina present, last one postitioned about thelevel of the 12th tooth; tooth crowns not flared orthickened; lingual face of each crown vertical.[Greer, 1979]
REMARKS. Sphenomorphus Group membersare distinguished from the Egernia andEugongylus Groups by possessing a Meckel’sgroove that remains open along the length of theventrolingual margin of the dentary (Hutchinson,1993). Two distinct size classes of membersrepresenting the Sphenomorphus group wereidentified within the deposit. Hutchinson (1993)recognised that while sexual dimorphism iscommon in skinks, it is only subtle. The large sizedifference between the two size classes isconsidered here to represent distinct species.
Until the taxonomy of those two species isbetter known, their significance in PleistoceneDarling Downs will remain unclear.
“Egernia group” (sensu Greer, 1979)
Tiliqua Gray 1825aTiliqua rugosa (Gray, 1825a)
(Fig. 8J)REFERRED MATERIAL. QMF44603-605, osteoderms.
DESCRIPTION. Osteoderms. Up to 10mm indiameter; thick, coarsely pitted; rugose surface.
REMARKS. The osteoderms of Tilqua rugosadiffer from all other Tiliqua as they are generallythicker and more coarsely pitted, functioning toform an armoured shield (Hutchinson, 1993).[Smith, 1976]
Cyclodomorphus Fitzinger, 1843Cyclodomorphus sp.
(Fig. 8K)REFERRED MATERIAL. QMF44639, dentary.
DESCRIPTION. Dentary. Near complete withlarge hemispherical teeth and closed Meckel’sgroove; ventral symphysal crest extends to thirdtooth; ten teeth present in dentary with tenth toothmarkedly larger than all anterior teeth; teethvariable in size, with acutely conical crowns;
specimen is adult as dental sulcus well defined,and dentary indicates cycles of toothreplacement.
REMARKS. Cyclodomorphus spp. are similar insize to Tiliqua spp., but are distinguished by amarkedly larger tenth tooth in the dentary(Hutchinson, 1993). The fragmentary nature ofthe fossil remains precludes a full comparison toother members of the genus. [Shea ,1990]
Family VARANIDAE Hardwicke & Gray,1827.
Varanus Merrem 1820Varanus sp.
(Fig. 8L)
REFERRED MATERIAL. QMF48166, vertebra.
DESCRIPTION. Vertebra broken dorsally;condyle overhanging, oblique articulation; cotyleoblique; centrum broad; neural canal round.
REMARKS. The fragmentary nature of thevertebra, particularly the lack of neural spine,precludes a full comparison to other Varanus spp.[Smith,1976].
Megalania Owen, 1860Megalania prisca (Owen, 1860)
(Fig. 8M)
REFERRED MATERIAL. QMF44615-17, osteoderms.
DESCRIPTION. Small , worm shapedosteoderms to 8mm in length, 3mm in diameter;growth lines evident.
REMARKS. Megalania prisca osteoderms growin the snout and nape regions of the lizard(Erickson et al., 2003). Growth lines present onthe osteoderms may reflect the age of theindividual (Erickson et al., 2003). [Hecht, 1975]
Family ELAPIDAE Boie, 1827gen. et sp. indet.
(Fig. 8N)
REFERRED MATERIAL. QMF44606-08,vertebrae.
DESCRIPTION. Vertebrae with long, acuteaccessory processes; hypapophysis arises nearlip of cotyle, extends posteriorly for half thelength of centrum, then deepens to taper into asharp point; parapophysial processes roundedanter ior ly; neural spine low, lateral lycompressed, does not extend posteriorly; fourpairs of foramina present.
DARLING DOWNS PALAEOECOLOGY 183
106
REMARKS. Elapid vertebrae considered hereare comparable in size to extant forms currentlyfound on the Darling Downs today, suchPseudechis australis and P. porphyriacus.[Smith,1976]. However, the fragmentary natureof the fossil material precludes a full comparisonto other members of the family.
Class MAMMALIA Linneus, 1758Order MARSUPIALIA Cuvier, 1817
Family DASYURIDAE Goldfuss, 1820; sensuWaterhouse, 1838
Sminthopsis Thomas, 1887Sminthopsis sp.
(Fig. 9A)REFERRED MATERIAL. QMF44637, dentary.
DESCRIPTION. Dentary. Small, gracile,deepest below M1; mental foramenposteroventral to root of M1. P3 ovoid in occlusaloutline; anterior cuspid reduced, lingual tomidline, forming anterior margin; central cuspidmassive, positioned one third from anteriormargin; blade-like crest runs posteriorly to asmall posterior cuspid. M1 anterior one-thirdtriangular, remainder sub-rectangular in occlusaloutline; talonid wider than trigonid; protoconidtallest cusp on crown, followed by metaconid,hypoconid, paraconid and entoconid; paraconidforms anterior margin slightly lingual to midline;protoconid posterobuccal to paraconid;metaconid transverse and slightly posterior toprotoconid; hypoconid posterobuccal toprotoconid; entoconid most posterior cuspforming posterolingual corner of crown; anteriorand posterior cingula small but distinct;
metacristids and hypocristids transverse to longaxis.
REMARKS. Identification to specific level is notpossible due to insufficient preservation ofdiagnostic features. [Archer,1981]
Dasyurus Geoffroy, 1796Dasyurus sp.
(Fig. 9B)
REFERRED MATERIAL. QMF44597, M4.
DESCRIPTION. M4. Ovoid in occlusal outline;paracone tallest cusp on crown followed indescending order by stylar cusp B, metacone andprotocone; paracone most anterior cusp,positioned in midline of crown; Stylar cusp Bposterobuccal to paracone; metacone postero-lingual to paracone; anterior cingulum absent.
REMARKS. M4 described above is much largerthan the corresponding tooth in all species ofDasyurus excepting D. maculatus. It is wellwithin the size range of extant D. maculatus,although differs in that: 1) it is not anteriorlyconcave in occlusal outline, 2) the metacone ispositioned more lingually, and 3) the anteriorcingulum is absent. [Ride,1964].
Sarcophilus Cuvier, 1837Sarcophilus sp.
(Fig. 9C)
REFERRED MATERIAL. QMF44640, C1.
DESCRIPTION. C1. Enamel constricted toanterior one-quarter of tooth; curved slightly inocclusal view and is deepest one-third from
184 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 9. A. Sminthopsis sp., left dentary; B. Dasyurus sp., M4; C. Sarcophilus sp., C1; D. Thylacinus cynocephalus,I1; E. Perameles bougainville, M1; F. P. nasuta, M3.
107
enamelised tip of tooth; root laterally compressedtapering to a blunt point.
REMARKS. QMF44640 compares well to thecorresponding tooth of recent Sarcophilus harissialthough is slightly larger and may represent thePleistocene S. laniarius. [Ride, 1964]
Family THYLACINIDAE Bonaparte, 1838
Thylacinus Temminck 1824Thylacinus cynocephalus (Harris, 1808)
(Fig. 9D)
REFERRED MATERIAL. QMF44643, I1.
DESCRIPTION. I1. Markedly curved in lateraland occlusal view; enamel constricted to theanterior one-quarter of tooth and tapers to anacute point; deepest and broadest half way alonglength of entire tooth; root laterally compressed,deep, with posterior half tapering to an acutepoint.
REMARKS. QMF44643 is morphologicallysimilar to the corresponding tooth of recentThylacinus cynocephalus. [Ride,1964]
Family DIPROTODONTIDAE Gill, 1872
Diprotodon Owen, 1838Diprotodon sp.
(Fig. 10A)
REFERRED MATERIAL. QMF44649, P3.
DESCRIPTION. P3. Sub-rectangular in occlusaloutline; bilophid with lophs connected by a highlingual crest; anterior lophid markedly largerthan posterior lophid; enamel thick with aworm-eaten puncate appearance.
REMARKS. Diprotodon sp. is distinguishedfrom other diprotodontids by possessing abilophodont lower premolar, with thick,punctated enamel. [Archer,1977]
Family THYLACOLEONIDAE Gill, 1872
Thylacoleo Owen 1858Thylacoleo carnifex Owen, 1858
(Fig. 10B)
REFERRED MATERIAL. QMF44642, I1.
DARLING DOWNS PALAEOECOLOGY 185
FIG. 10. A. Diprotodon sp., P3; B. Thylacoleo carnifex, I1; C. Aepyprymnus sp., M3; D. Troposodon minor, rightdentary; E. Procoptodon pusio, left dentary; F. Macropus agilis siva, right dentary; G. M. titan, right dentary; H.Protemnodon anak, left dentary; I. P. brehus, right maxilla.
108
DESCRIPTION. I1. markedly curved in occlusalview with enamel confined to anterior and lateralsurface in a U shape; occlusal wear surfaceconcave; root deep and laterally compressed.
REMARKS. Thylacoleo carni fex isdistinguished from other members of the genusby its significantly larger size. [Wells et al., 1982]
Family POTOROIDAE Gray, 1821; sensuArcher & Bartholomai, 1978
Aepyprymnus Garrod, 1875Aepyprymnus sp.
(Fig. 10C)
REFERRED MATERIAL. QMF44652, M3.
DESCRIPTION. M3. metalophid low and verythin, but distinct; postmetacrista connects toposterior cingulum to form a very large and fairlydeep pocket-like structure on posterior margin oftooth; premetacrisa well defined.
REMARKS. Fragmentary material precludes afull comparison to Aepyprymnus rufescens, theonly the only known member of the genus. [Tate,1948]
Family MACROPODIDAE Gray, 1821Subfamily STHENURINAE Glauert, 1926
Procoptodon Owen 1874Procoptodon pusio (Owen, 1874)
(Fig. 10E)
REFERRED MATERIAL. QMF44648, dentary.
REMARKS. Dentary. Short, deep and robust;buccal groove on ramus well defined.Lower molars. Sub-rectangular in occlusaloutline, with slight constriction in midvalley;base of molars swollen and lophids high, convexanteriorly; enamel crenulated, though smooth onlingual and buccal lateral surfaces; anteriorcingulid is high, angled slightly lingually.
REMARKS. Propcoptodon pusio isdistinguished from other members of the genusby a combination of characters including: 1) itsslightly smaller size, 2) lacking a distinctposthypocristid, and 3) less extensive transverseanterior portion of paracristid (Prideaux, 2004).The horizon from which the P. pusio material wascollected is unknown. Procoptodon is restrictedto Pleistocene deposits, though may have had itsorigins in the late Tertiary (Bartholomai, 1970;Prideaux, 2004). [Prideaux, 2004]
Subfamily MACROPODINAE Gray, 1821
Troposodon Bartholomai 1967Troposodon minor (Owen, 1877b)
(Fig. 10D)
REFERRED MATERIAL. QMF44646-47, dentaries.
DESCRIPTION. Dentary. Shallow and gracile;symphysis elongate with ventral surfacemarkedly lower than ventral surface of ramus.Lower molars. Subrectangular in occlusaloutline, with slight kink in midvalley; lophs low,angled slightly lingually, and slightly concaveanteriorly; preparacristid links to anteriorcingul id; premetacr is t id descendsanterolingually from metaconid to fuse withpreparacristid.
REMARKS. Troposodon minor is placed withinMacropodinae rather than Sthenurinae followingPrideaux (2004). T. minor is easily distinguishedfrom other members of the genus by beingintermediate in size between the larger T. kentiand smaller T. bowensis. [Flannery and Archer,1983]
Macropus Shaw 1790Macropus agilis siva (De Vis, 1895)
(Fig. 10F)
REFERRED MATERIAL. QMF44638, I1; QMF44655,dentary; QMF44656-7, maxillary fragments.
DESCRIPTION. Dentary. Gracile, with grooveon ventral surface of ramus extending fromposterior of symphysis to below posterior root ofM2; symphysis elongated and diastema long. I1.Elongated and deeply rooted; slightly curved inboth lateral and occlusal views. P3. Elongated,blade-like; small ridges descend lingually andbuccally from apex of longitudinal ridge.Lower molars. Increase in size from M1-3;sub-rectangular in occlusal outline, with slightconstriction in midvalley; hypolophid wider thanprotolophid; lophids high; cristid obliqua high;posterior cingulid absent. DP2 elongated, broadposteriorly; small ridges descend main crest;posterolingual fossette shallow. DP3 molariform;subrectangular in occlusal outline with slightconstriction in midvalley; lophs low; metalophwider than protoloph; posterior fossettemoderately developed. M1 sub-rectangular inocclusal outline, with slight constriction inmidvalley; high lophs; metaloph broader thanprotoloph; midlink moderately high; posteriorfossette well developed.
186 MEMOIRS OF THE QUEENSLAND MUSEUM
109
REMARKS. Macropus agi l is s iva isdistinguished from other members of the genusby possessing a combination of featuresincluding: 1) elongate diastema, 2) P3 as long asM1, 3) lower molars high crowned, with highlinks, and lacking posterior cingula, 4) elongateupper premolars, and 5) upper molars elongatedwith high crowns, slight forelink and moderatemidlink. [Bartholomai,1975]
Macropus titan Owen, 1838(Fig. 10G)
REFERRED MATERIAL. QMF44645, dentary.
DESCRIPTION. Dentary. moderately deep, thebase of symphysis slightly lower than the base ofhorizontal ramus.Lower molars. Sub-rectangular in occlusaloutline, slightly constricted across talonid basin;lophids high and curved slightly anteriorly;forelink high, curving anteriorly to meet a highanterior cingulid; posterior fossette present onposterior loph.
REMARKS. Macropus titan is distinguishedfrom other members of the genus by acombination of features including: 1) its largesize, 2) elongate diastema, 3) high crowned,elongated lower molars with slightly curvedlophids, high links and high anterior cingulum(Bartholomai, 1975). An additional dentaryfragment, QMF44644, is referred to M. sp. cf. M.titan. The molars are within the size range of M.titan, however it differs in that: 1) the dentary ismarkedly more robust and deep, 2) forelink isslightly lower, 3) anterior cingulid broader, and4) cristid obliqua is higher. [Bartholomai,1975]
Protemnodon Owen 1874Protemnodon anak (Owen, 1874)
(Fig. 10H)
REFERRED MATERIAL. QMF44650, skull;QMF44658, dentary.
DESCRIPTION. Dentary. Moderately shallow,with elongated symphysis ascending anteriorly atlow angle; mental foramen oval shaped, close todiastemal crest. P3. Elongated, blade-like;exceeds length of M1.Lower molars. Sub-rectangular in occlusal viewwith slight constriction in midvalley; lophidshigh, concave anteriorly with high forelink;posterior cingulid small P3. Elongate; crownconcave buccally; high longitudinal crest,slightly concave buccally; transected by fourvertical blades.
Upper molars. Sub-rectangular in occlusaloutline, slightly constricted across mid valleys;midlink strong; forelink absent; anteriorcingulum slightly swollen.
REMARKS. Protemndon anak is distinguishedfrom other Pleistocene members of the genus by acombination of characters including: 1) smallsize, 2) P3 elongate, concave bucally, with highlongitudinal crest, and longer than M4, 3) M3 andM4 lacking cuspules in the lingual portion of themidvalley. [Bartholomai,1973]
Protemnodon brehus (Owen, 1874)(Fig. 10I)
REFERRED MATERIAL. QMF44627, maxilla.
DESCRIPTION. Upper molars. Sub-rectangularin occlusal outline, slightly constricted acrossmidvalley; anterior cingula broad; forelinkabsent; strong ridge curves from paracone intocrista obliqua.
REMARKS. Protemnodon brehus isdistinguished from other members of the genusby: 1) its large size, and 2) lacking a lingualcuspule in the midval ley of M3 - 4 .[Bartholomai,1973]
Order RODENTIA Bowdich, 1821.Family MURIDAE Illiger, 1811
Pseudomys Gray 1832Pseudomys sp. 1 & 2
(Fig. 11A)REFERRED MATERIAL. Sp. 1: QMF44609-10,maxillae; Sp.2: QMF48168, maxilla.
DESCRIPTION. Maxilla. Anterior portion ofzygomatic arch not broadened; molar alveolipattern 3(M1) 3(M2) 3(M3). M1. Relativelyelongate; T7 absent; three rooted, with onelingual root.
REMARKS. Pseudomys sp. 1 and 2 could not beidentified to specific level considering the natureof the fragmentary remains. Pseudomys sp. 1 fitswithin the size class of extant P. australis.Pseudomys sp. 2 is smaller, approximating thesize of extant P. delicatulus . [Jones &Baynes,1989]
Rattus sp. (Fischer, 1803)(Fig. 11B)
REFERRED MATERIAL. QMF44611-12, isolatedmolars; QMF44613-14, maxillae.
DESCRIPTION. M1. Cusps rounded in occlusaloutline; two lingual cusps; five rooted, with two
DARLING DOWNS PALAEOECOLOGY 187
110
lingual alveoli. M2. Four rooted, arranged in asquare pattern.
REMARKS. Rattus spp. are distinguished fromother murid genera by possessing an M2 that hasfour roots, arranged in a square pattern (Knox,1976). [Jones & Baynes,1989]
MATERIAL ASSIGNED TO OTHER TAXA
Teleostei fam. gen. et sp. indet. (Fig. 8A); QMF44634-36,vertebrae.
Limnodynastes tasmaniensis (Gnther, 1858) (Fig. 8B);.QMF43978-43985, ilia.
L. sp. cf. L. dumerili (Peters, 1863) (Fig. 8C);QMF43995-43997, ilia.
?Limnodynastes (Fitzinger, 1843)(Fig. 8D); QMF44000,ilium.
Neobatrachus sudelli (Lamb, 1911) (Fig. 8E);QMF44001-44002, ilia,
Kyarranus sp. (Fig. 8F); QMF44003, ilium.
Chelidae gen. et sp. indet. (Fig. 8G); QMF44626;QMF44641, carapace fragments.
Perameles bougainville (Quoy & Gaimard, 1824) (Fig.9E); QMF44549, RM1,.
Perameles nasuta (Geoffroy, 1804) (Fig. 9F);QMF44566, LM3.
ECOLOGICAL REMARKS
Elements of the fauna are here listed withminor pertinent ecological comments asappropriate.
MOLLUSCS. The invertebrate fauna is rich anddiverse. Four families of land snails arerepresented, comprising seven species, as well astwo families of freshwater snails, containing twospecies (J. Stanisic, pers. comm.). Freshwaterbivalves are also common throughout the mainfossiliferous units.Velesunio ambiguus (Philippi, 1847): This mostcommon species of the Australian Unioniodea,occurs in coastal and interior rivers throughoutSouth Australia, Victoria, New South Wales andQueensland (Lamprell & Healy, 1998). Velesunioambiguus is a typical floodplain speciescommonly found in billabongs and creeks; itrarely occurs in large rivers, except in the vicinityof impoundments (Sheldon & Walker, 1989).The exclusion of V. ambiguus from larger riversprobably reflects its weak anchorage (Sheldon &Walker, 1989).Extant populations of Velesunio ambiguus arecommon throughout the creeks and tributaries ofthe Darling Downs. Additionally, V. ambiguushas been recorded from the Pleistocene DarlingDowns (Gill, 1978; Sobbe, 1990).Corbicula (Corbiculina) australis (Deshayes,1830): C. (C.) australis occurs in coastal andinland rivers and streams. It is a hermaphroditicspecies that has a benthic crawling larva thatmakes it possible for C. (C.) australis to spreadrapidly (Britton & Morton, 1982).Extant C. (C.) australis are common throughoutwater courses of the Darl ing Downs.Additionally, C. (C.) australis has been reportedfrom the Pleistocene Darling Downs (Gill, 1978;Sobbe, 1990).Thiara (Plotiopsis) balonnensis (Conrad,1850): T. (P.) balonnensis was the most commonidentifiable species recovered from the deposit. Itwas collected in-situ from shell beds up to 10cmthick. It is the most widespread of the Australianthiraids, common throughout the Murray-Darling River system.Extant populations commonly occur in ponds,dams and rivers (Smith & Kershaw, 1979).Extant populations of Thiara (Plotiopsis)balonnensis are present on the Darling Downs.Thiara (P.) sp. has been reported from the fossilrecord of the Pleistocene Darling Downs (Gill,1978; Sobbe, 1990).Gyraulus gilberti (Dunker, 1848): Planorbidsare a common Australian family of freshwatersnails. The Planorbidae are confined to waterswith low salinity and are generally associatedwith macrophytes or algae. Gyraulus has been
188 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 11. A. Pseudomys sp. 1, left maxilla; Rattus sp.,left maxilla.
111
reported in the Tertiary fossil record of northernAustralia (McMichael, 1968).Saladelos sp.: Saladelos sp. commonly occur inclosed to open forest to vine thicketed habitats (J.Stanisic pers. comm.).Strangesta sp.: Strangesta sp. commonly occurunder dry, dense ground cover in dry forest towoodland scrub, and vine thickets (Smith &Kershaw, 1979; J. Stanisic pers. comm.).Coenocharopa sp.: Coenocharopa sp. aregenerally found in warmer temperate forestthickets to cool, dry, sub-tropical notophyll vineforests from the central to north eastern coast ofthe Australian continent (Stanisic, 1990).Gyrocochlea sp. 1 and 2: Members ofGyrocochlea typically inhabit dry to humidsub-tropical vine forests and prefer to live underlogs (Stanisic, 1990). Like most charopids,Gyrocochlea sp. are common throughout centraleastern Australia (Stanisic, 1990).Austrosuccinea sp.: Austrosuccinea are landsnails that are found in a variety of habitatsranging from marches and swampyenvironments, to sand dunes and seasonally drystream basins (Solem, 1993).Xanthomelon pachystylum (Pfeiffer, 1845):Camaenids are among the most diverse ofAustralian land snails. The Australian camaenidfossil record is scant with only a few knownrecords (Ludbrook, 1978, 1984; McMichael,1968; Kear et al., 2003). X. pachystylum is aherbivorous species associated with dense vinethickets (J. Stanisic, pers. comm.).
AMPHIBIANSLimnodynastes tasmaniensis (Gnther, 1858):Extant L. tasmaniensis populations are commonover much of eastern Australia and have beenrecorded in a range of habitats ranging from wetcoastal environments to dry, arid regions(Cogger, 2000).Extant populations of L. tasmaniensis have beenrecorded from the Darling Downs (Ingram &Longmore, 1991).L. sp. cf. L. dumerili (Peters, 1863): Extantpopulations have been recorded in most habitats,with the exception of alpine areas, rainforest, andextremely arid zones (Cogger, 2000).Extant populations of L. dumerili have beenrecorded from the Darling Downs (Ingram &Longmore, 1991).Neobatrachus sudelli (Lamb, 1911)
Extant populations of Neobatrachus sudellioccur throughout southeastern Australia,commonly occurring in open woodlands withgrassy understories (Cogger, 2000).
Kyarranus sp.Extant Kyarranus populations occur in areas of
dense ground cover and thickets in isolatedmontane forest patches on the Great DividingRange in southeastern Queensland andnortheastern New South Wales (Tyler, 1991).
REPTILES
Tympanocryptis “lineata” (Peters, 1863):Extant T. lineata populations occur in a variety ofsemi-arid to arid environments in centralAustralia. T. lineata commonly occur in earthcracks, grass or ground litter on desert sandhills,to black soil plains (Cogger, 2000).
Extant T. lineata populations have been recordedfrom the Darling Downs (Covacevich & Couper,1991). Additionally, agamids have previouslybeen recognised in the Darling Downs fossilrecord (Bennett, 1876; Lydekker,1888; Molnar &Kurz,1997).
“Sphenomorphus Group” sp. 1 and 2: Theecology of extant members of theSphenomorphus group is varied and includes taxathat burrow in soil, burrow under leaf litter, havesemi-amphibious lifestyles and others that arefound in rocky arid environments (Cogger,2000).
Til iqua rugosa (Gray, 1825a): Extantpopulations of T. rugosa are found in a range ofhabitats including coastal heaths, dry sclerophyllforest, woodlands, mallee, and arid Acacia andeucalypt scrublands. T. rugosa shelters underfallen timber and leaf litter spinifex wheninactive (Cogger, 2000).
Cyclodomorphus sp.: Cyclodomorphus spp. areground dwelling skinks, although commonlyclimbs on low growing vegetation. ExtantCyclodomorpus populations have been recordedfrom wet to dry sclerophyll forest, commonlyfound under leaf litter or areas with low groundcover (Cogger, 2000).
Varanus sp.: Extant Varanus sp. populationshave been recorded in a wide range of habitatsfrom deserts to rainforest, and may havesemi-aquatic, terrestrial, or arboreal locomotivestrategies.
Extant Varanus populations have beenrecorded from the Darling Downs (Covacevich &Cooper, 1991). Additionally, Varanus sp. has
DARLING DOWNS PALAEOECOLOGY
112
been recorded from the Pleistocene DarlingDowns (Wilkinson, 1995).
Megalania prisca (Owen, 1860): Molnar (1990)suggested that M. prisca was unlikely to havebeen arboreal, though it may have had asemi-aquatic life style.
Megalania prisca has been recorded from severalfossil localities on the Darling Downs (Molnar &Kurz, 1997).
Other elements: Indeterminate chelid and elapidremains have been found in the deposit.
MARSUPIALS
Sminthopsis sp.: Extant Sminthopsis spp.populations occur in open to closed habitats(Strahan, 1995).
Extant populations of S. murina have beenrecorded on the Darling Downs (Van Dyck &Longmore, 1991).
Dasyurus sp.: Dasyurus maculatus is the largestextant native mammalian carnivore on themainland of Australia. Dasyurus spp. are partlyarboreal and occur on the eastern margin of thecontinent and Tasmania in a wide range ofwooded habitats including rainforests, openforests, woodlands, and riparian forest. Den sitescommonly include caves, rock crevices andhollow logs.
Sarcophilus sp.: Once common over the centraland eastern portions of the Australian continent,Sarcophilus is now restricted to Tasmania whereit is abundant in dry sclerophyll forest andwoodlands that are interspersed with grasslands(Jones, 1995).
Thylacinus cynocephalus (Harris, 1808): Priorto European arrival in Australia, extant T.cynocephalus was restricted to Tasmania beforeover hunting led to its subsequent extinction. T.cynocephalus was once common in open forestand woodland (Dixon, 1989).
Perameles bougainville (Quoy & Gaimard,1824): Extant populations of P. bougainville arerestricted to Bernier and Dorre Islands, SharkBay, Western Australia, although once occurredover much of semi-arid Australia (Friend &Burbidge, 1995). Extinction on the mainland hasbeen attributed to the effects of habitatdisturbance and introduction of non-nativepredators by Europeans. P. bougainville was oncecommon on the mainland in a range of habitatsincluding dense scrub thickets, open saltbushplains and stoney ridges bordering scrubland(Friend & Burbidge, 1995).
Perameles nasuta (Geoffroy, 1804): ExtantPerameles nasuta populations occur in a widerange of habitats including rainforests, wet to drywoodlands, and areas with very little groundcover (Stoddart, 1995). It is a common andwidely distributed species with a wide range ofhabitat tolerances, and its presence in the fossilrecord is of li t t le palaeoenvironmentalsignificance.Extant Perameles nasuta populations arecommon on the Darling Downs.Diprotodon sp.: Diprotodon spp. are generallyregarded browsers of shrubs and forbs andprobably occupied an open woodland to savannahabitat (Murray, 1984).Thylacoleo carnifex (Owen, 1858) : T. carnifexmay have occupied an open forest habitat(Murray, 1984). T. carnifex filled the ‘large cat’niche of the Australian Pleistocene, and mayhave had the ability to kill Diprotodon-sizedanimals (Wroe, et al., 1999). The lower incisorfunctioned as a stabbing or piercing tooth thatoccludes with the upper incisors where it acts asan anvil against which food is restrained (Wells etal. 1982).T. carnifex has been recorded from several fossillocalities on the Darling Downs (Molnar & Kurz,1997).Aepyprymnus sp.: Extant A. rufescenspopulations occur in a variety of habitats rangingfrom wet sclerophyll to dry open woodlands, butonly occupy areas with sparse grassyunderstories commonly adjacent to areas ofdense undergrowth (Dennis & Johnston, 1995).Procoptodon pusio (Owen, 1874): Procoptodonspp. were adapted for a diet of highly fibrousvegetation (Prideaux, 2004).P. pusio has been recorded from several fossillocalities on the Darling Downs (Molnar & Kurz,1997; Prideaux, 2004).Troposodon minor (Owen, 1877b): Troposodonminor is generally regarded as a semi-browser(Bartholomai, 1967). Flannery & Archer (1983)suggested that at least two species of Troposodonoccurred sympatrically at most Plio-Pleistocenelocalities. However, T. minor remains the onlymember of the genus recorded at QML1396.Troposodon minor is relatively common inPleistocene Darling Downs deposits (Molnar &Kurz, 1997).Macropus agilis siva (De Vis, 1895): ExtantMacropus agilis populations favour savannahwoodland or open forest habitats (Bell, 1973).
190 MEMOIRS OF THE QUEENSLAND MUSEUM
113
M. a. siva was common and widespread on thePleistocene Darling Downs (Molnar & Kurz,1997).Macropus titan (Owen, 1838): The highcrowned molars M. titan are typical of grazingspecies (Bartholomai, 1975).M. titan was one of the most common andwidespread megafauna species on the DarlingDowns, being recorded from 21 fossil deposits(Molnar & Kurz, 1997).Protemnodon anak (Owen, 1874),Protemnodon brehus (Owen, 1874):Protemnodon spp. are regarded as grazers(Bartholomai, 1973).P. anak and P. brehus have been recorded fromover 30 fossil localities on the Darling Downs(Molnar & Kurz, 1997).
RODENTSPseudomys sp. 1 & 2: Extant Pseudomys spp.populations occur in a wide variety of habitatsfrom sparsely vegetated deserts to closedsclerophyll forests (Strahan, 1995). Until thetaxonomy of the Pleistocene Darling DownsPseudomys spp. is better known, theirpalaeoenvironmental significance will remainunclear.Pseudomys spp. have been recorded from thePleistocene Darling Downs (Archer & Hand,1984).
Rattus sp.: In terms of abundance and diversity,Rattus is the most diverse extant murid genus inQueensland. Extant Rattus populations are found ina number of habitats including rainforests,woodlands, and savanna grasslands.
Extant Rattus spp. populations (native andintroduced) have been recorded from the DarlingDowns (Covacevich & Easton, 1974). Additionally,Rattus sp. has been reported from the PleistoceneDarling Downs (Archer & Hand, 1984).
DATING.
The AMS14C dating results of freshwaterbivalves and charcoal indicate that deposition ofHorizon B occurred 44300± 2200 to >49900 andHorizon D at 45150±2400 (Table 9). However,those results should be considered as minimumages only considering the fact that the QML1396assemblage appears to be close the limits of theAMS14C dating technique. Owing to theimportance associated with dating latePleistocene megafauna extinction and climate
change, it is desirable to further test the datingresults presented here.
DISCUSSION
SEDIMENTOLOGY. The deposit representsboth high velocity lateral channel deposition andlow velocity vertical accretion. The lowerfossiliferous unit, Horizon B, represents the mostsignificant input of sandy deposits in thesedimentary environment. Horizon B is laterallycontinuous for more than 70 metres. However,the horizon is largely unexposed and positionedbelow the modern water table, therefore theprecise lateral extent of Horizon B is unknown.Horizon B is characterised by: 1) abundantfreshwater mollusc fossils, including large-sizedbivalves; 2) vertebrate fossils; 3) fluviallytransported sediments (including rounded basalt,calcrete and sandstone pebbles and cobbles); and4) upwardly fining grain size. The geometry ofHorizon B and the interpreted sedimentaryprocesses suggest that deposition took place inthe main channel. Horizon B accumulated underhigher velocity deposition than Horizon Dconsidering the significantly larger grain sizesand preponderance of larger-sized bivalves (Fig.2, Table 1).
The fine brown-grey clay unit, Horizon C,suggests a period of low velocity deposition.Mollusc shells are rare, however, freshwatergastropods (Thiara (Plotiopsis) balonnensis) areslightly more common than freshwater bivalves.The presence of freshwater molluscs in thehorizon are consistent with the proximity to thechannel.
Horizon D is laterally continuous forapproximately 30 metres. Horizon D ischaracterised by: 1) discontinuous lenticularsandy and shelly beds; 2) mud cracks in-filledwith fine clays; 3) vertebrate fossils; and 4)fluvially transported sediments (includingrounded basalt, calcrete and sandstone pebbles).The facies association of lenticular shelly beds
DARLING DOWNS PALAEOECOLOGY 191
ANSTO code sample horizon conventional 14C age �
2� error
OZG855 charcoal D 45150 � 2400
OZG547 bivalve B >49900
OZG548 bivalve B 44300 � 2200
TABLE 9. AMS 14C dating results of charcoal andVelesunio ambiguus samples from QML1396. Agesquoted are radiocarbon ages, not calendar ages. Agesrounded according to Stuiver & Polach (1977)
114
overlies the low velocity brown-grey clay unit (incontinuity with the channel deposit). Freshwatergastropods in Horizon D show polymodal currentdirections indicating that they were not depositedas traction load in flowing water. The datasuggest that deposition occurred as overbankdeposits on the floodplain adjacent to the channelbelt. A succession of several small overbankdepositional events created superposed shellylenses up to 100mm thick. The depositionalset t ing of Horizon D is interpreted asrepresenting a series of small crevasse splays andsubsequent drying pools in the overbank thatresulted from minor flood events. It ishypothesised that as the pools evaporated,stranded gastropods moved into the deeper partsof the pools (hence showing polymodalorientations) eventually dying when the poolsevaporated.
Overlying fine-grained deposits of the upperunits represent vertical accretion on thefloodplain (Fig. 2, Table 1). The occurrence ofiron nodule formation in the upper units of theprofile reflect alternating periods of oxidationand reducing conditions due to watertablefluctuations. Additionally, in-situ, white tobrownish-grey mottled calcrete formation in theupper units is related to similar watertablefluctuations. Mottled calcretes are chemicallyprecipitated in the freshwater phreatic zone of thewatertable, and are primarily related to the lateralmovement and percolation of alkaline waters inthe soil profile (Arakel & McConchie, 1982). Theclose association of the formation of in-situmottled calcretes and ferruginous oxides areindicative of a response to an increasingly aridenvironment, subsequent to deposition of themajor fossiliferous horizons.
TAPHONOMIC HISTORY OF BONES.
Numerous unidentifiable bone fragmentsrecovered from the deposit exhibited a range ofabrasion and weathering characteristics.However, the following taphonomic conclusionsare largely based on identifiable vertebrateremains horizons B and D. Better preservedspecimens may yield more accuratepalaeobiological and palaeoecologicalinformation than unidentifiable fragments.However, it is recognised that some componentsof the assemblage may have had differenttaphonomic pathways leading to their finaldeposition.
It is unlikely that acidic ground waters haveplayed a role in the diagenesis of fossil material
from either horizon, considering the high degreeand diagentically unaltered preservation ofcalcareous material (i.e. mollusc shell andcalcrete) that has been identified in the deposit.Additionally, root etching of vertebrate fossilmaterial was not observed. Few of theidentifiable specimens indicate any significantpre-burial weathering (sensu Behrensmeyer,1978).
There were several biases in the preservation ofdifferent faunal groups and skeletal elementsobserved in the deposit. For squamates, there wasa noticeable lack of post-cranial materialpreserved in the deposit in comparison tomammals. Similar biases between terrestrialnon-mammals and mammals have beenidentified within fossil deposits of the KoobiFora Formation of Kenya (Behrensmeyer, 1975).Additionally, within the Agamidae andScincidae, differences were observed in thepreservability of cranial and dental elements. Thedifferences may be related to minor differences inbone density or structure. However, few previousstudies have addressed the causes of suchpreservational biases, focusing predominantly onthe accumulation of fossil mammals. In theabsence of comparative data on squamatetransportability and preservability in fluvialsystems, it is difficult to explain such biases in thefossil record.
Large-sized mammals are better preserved inHorizon B than Horizon D, but small-sized taxaare generally absent from Horizon B. Bones andshells act as sedimentary particles in fluvialsystems and may have settling velocities that arerelated to equivalent-sized spherical quartzgrains (Behrensmeyer, 1975). Therefore, if thesize of bone and shells are relative to the size ofthe surrounding grains, then coarse-grained unitssuch as Horizon B would be expected to containlarger-sized skeletal elements or species thanfiner-grained units such as Horizon D. Thathypothesis may equally explain: 1) whylarge-sized bivalves are more common inHorizon B than Horizon D; 2) why the Horizon Bassemblage is dominated by large-sizedvertebrates, and Horizon D by small-sizedvertebrates; and 3) the differences between therelative abundance of skeletal elements of largeand small mammals within Horizon D.
Assemblages of both horizons are generallycharacterised by: 1) low levels of post-crania; 2)high degrees of bone breakage; 3) low degrees ofabrasion; and 4) low degrees of weathering. A
192 MEMOIRS OF THE QUEENSLAND MUSEUM
115
comparison of the abundance of skeletalelements to experimental data of skeletal elementtransportability in fluvial systems indicates thatboth units contain elements that are among thelast to be transported in flowing water. Thatsuggests that horizons B and D represent bone lagdeposits. The high degree of breakage of skeletalelements suggests that the vertebrate remainswere subjected to considerable forces.Additionally, the loss of limb bone ends mayreflect a density mediated destruction oflower-density bone (distal and proximal ends)and that the higher-density bone shafts were notdestroyed (Rapson, 1990). The low degree ofbone abrasion and low degree of pre-burialweathering indicate that the vertebrates diedwithin close proximity to the final point ofdeposition and were probably buried rapidly afterdeath. Additionally, no elements were recoveredthat show the effects of digestion, polishing orgnawing that may be attributable to predatoraccumulation (sensu Andrews, 1990; Sobbe,1990). Collectively, the data indicate that thevertebrate material was accumulated andfluvially transported into the deposit from thesurrounding proximal floodplain.
PALAEOENVIRONMENTALINTERPRETATION
Megafauna species are less abundant and lesswell preserved in Horizon D (low-energyoverbank deposi t ion) than Horizon B(high-energy channel deposition), and allvertebrate taxa smaller than Sarcophilus sp. (~8kg) are absent from Horizon B (Figure 6). Threehypotheses could explain the faunal differences:1) Megafauna went locally extinct progressivelybetween the time of deposition of Horizons B andD (the age of the two QML1396 assemblagesmay bracket the terminal extinction event of theAustralian megafauna [~46ka; Roberts et al.,2001a]); 2) Sampling by the creek system wasbiased towards the collection of small-sizedspecies in Horizon D; or 3) Larger-sized bonesmay not have been able to be transported intooverbank deposits from flood events (large bonesin the overbank deposits may be derived directlyfrom the proximal floodplain rather than fromfluvial transport). Additionally, a third of thelarge-sized taxa that are present in Horizon B, butabsent from Horizon D, are carnivorous species(Sarcophilus sp., Thylacinus cynocephalus &Thylacoleo carnifex; Table 2). Hence, the rarityof carnivorous taxa in the Pleistocene DarlingDowns might be assumed regardless. However,
considering the taphonomic sampling biases ofthe Pleistocene channel, it is difficult toaccurately compare habitat and speciesdifferences between the Horizon D and Bassemblages, and hence, directly demonstrate theextinction of megafauna temporally based ondata from QML1396.
Large-sized taxa previously used to makeinterpretations about Darling Downs Pleistocenepalaeoenvironments are present in the Horizon Bassemblage, thus in agreement with previousbroad interpretations of a woodland and opengrassland Pleistocene habitat (Table 10). All ofthe mammals recorded from Horizon B are eitherlocally or totally extinct.
The Horizon D assemblage consists of largeand small-sized taxa that are extant, locally ortotally extinct. The small-sized faunas haverevealed a series of increasingly complexterrestrial habitats, some that have not previouslybeen documented in the Pleistocene DarlingDowns. It appears that at the time of deposition ofHorizon D, a suite of habitats existed thatconsisted of grasslands, open woodlands withgrassy understories, and scrubby vine-thicketedhabitats (Table 11). A scrubby vine thicketedhabitat is indicated predominantly by the diverseland snail fauna. That interpretation isadditionally supported by the presence ofKyarranus, a frog genus whose extant membersare restricted to dense understories and thickets.Vine thickets are common on the Great Dividing
DARLING DOWNS PALAEOECOLOGY 193
Species freshwater openwoodland
opengrassland
Velesunio ambiguus x
Corbicula(Cobiculina) australis x
Thiara (Plotiopsis)balonnensis x
Sarcophilus sp.* x
Thylacinuscynocephalus** x
Diprotodon sp.** x x
Thylacoleo carnifex** x
Troposodon minor** x
Macropus agilissiva** x
M. titan** x x
Protemnodon anak** x x
P. brehus** x x
TABLE 10. Preferred and inferred habitat types ofextant and fossil taxa recorded from Horizon B. (*Extinct on Darling Downs; ** Totally extinct).
116
Range today and support a similar land snailfauna (J. Stanisic, pers. comm.). Additionally,scrubby and closed habitats have previously beensuggested for late Pleistocene deposits of the
Kings Creek catchment (Price, 2004; Price et al.,in press). Woodlands were likely to have beenopen sclerophyll, interspersed with sparse grassyunderstories. That interpretation is highlightedby the presence of taxa such as Austrocuccineasp., Neobatrachus sudelli, Aepyprymnus sp., andMacropus agilis siva. Grasslands were likelydominated by large browsing macropodsincluding Macropus titan and Protemnodon spp.Small agamid lizards such as Tympanocryptislineata probably occupied a similar open habitat,utilizing the earth cracks within black soils.
There are few modern analogues to explain thehigh habitat diversity indicated by the faunarepresented in the Horizon D assemblage.However, considering the relatively constrainedsampling area of the Kings Creek palaeo-catchment, it is unlikely that the diverseQML1396 assemblage resulted from thesampling of wide geographic areas outside theimmediate catchment area (i.e. by long distancefluvial transport). Additionally, taphonomic dataindicates that while the assemblage washydraulically transported, the components wereunlikely to have been transported over longdistances. Collectively, those data suggest that amosaic of grassland, sclerophyllous woodlands,and scrubby vine-thicketed habitats were presentwithin the geographically small PleistoceneKings Creek catchment. Non-analogueassociations of taxa (sensu Lundelius, 1989, as‘disharmonious’ associations) from other sites inthe Kings Creek catchment (e.g. bandicoots fromQML796) support the hypothesis that avegetative mosaic of habitats was present duringthe late Pleistocene (Price, 2004).
Comparison of such Pleistocene habitats tothose of the modern Kings Creek catchment isdifficult considering extensive pastoral activitieswhich have altered natural vegetation in theregion since the early 1840’s. Even where naturalremnant vegetation survives, its current structureand floristics do not necessarily reflect itspre-settlement character. However, a review ofover 5,000 land surveys from periods of theinitial settlement of the Darling Downs indicatesthat the region surrounding the immediate area ofdeposition of QML1396 was dominated bygrasslands, with Eucalyptus orgadophilawoodlands with grassy or shrubby understoriesbeing found closer to the range (Fensham &Fairfax, 1997). Based solely on the numbers ofdifferent species representing the interpretedPleistocene habitats of QML1396, it is evidentthat taxa indicating open grassland habitats are
194 MEMOIRS OF THE QUEENSLAND MUSEUM
species
fres
hwat
er
vine
-thi
cket
scru
blan
d
cols
edw
oodl
and
open
woo
dlan
d
open
/gra
ssla
nd
Velesunio ambiguus X
Corbicula (Cobiculina) australis X
Thiara (Plotiopsis) balonnensis X
Gyraulus gilberti* X
Coencharopa sp.* X
Gyrocochlea sp. 1* X
Gyrocochlea sp. 2* X
Austrocuccinea sp.* X X X
Xanthomelon pachystylum* X
Strangesta sp.* X X
Saladelos sp.* X
Teleost X
Limnodynastes tasmaniensis X X X X X
L. sp. cf. L. dumerili X X X X X
?Limnodynastes X X X X X
Neobatrachus sudelli* X X
Kyarranus sp.* X X
Chelid X
Tympanocryptis “lineata”* X
“Sphenomorphus Group” sp. 1 X X X X X
"Sphenomorphus Group” sp. 2 X X X X X
Tiliqua rugosa* X X X
Cyclodomorphus sp.* X X X X
Varanus sp. X X X X X X
Megalania prisca** X X X
Elapid X X X X X X
Sminthopsis sp. X X X X X
Dasyurus sp. X X
Perameles bougainville* X X
Pe. nasuta X X X X X
Aepyprymnus sp X
Macropus agilis siva** X
M. titan** X X
Protemnodon anak** X X
Pr. brehus** X X
Pseudomys sp.* X X X X X
Rattus sp. X X X X X
TABLE 11. Preferred and inferred habitat types ofextant and fossil taxa from Horizon D. (* Extinct onDarling Downs; ** totally extinct).
117
the minority, and that species favouringwoodlands and scrubby, vine thicketed habitatsdominate the assemblage (Tables 10 & 11). It ishypothesised that the immediate areasurrounding the Pleistocene watercourse wasdominated by woodlands, scrublands and vinethickets, and that open grasslands were situatedfarther away from the creek. That interpretationsuggests that there must have been significantenvironmental change between the time ofdeposition of QML1396 and present, and thatwould have reflected contraction of woodlandsand vine thickets closer to the range, andexpansion of grasslands in the catchment area.
Deposition of the QML1396 assemblageoccurred around the time of the extinction of theAustralian megafauna, i.e. ~46ka (Roberts et al.,2001a). Hence, it is an extremely importantPleistocene assemblage as it provides detailedinformation about habitats and environmentsduring a critical period for Australian megafauna.The two major hypotheses surrounding theextinction of Australian megafauna are: 1) anaturally driven climate change that coincidedwith the last glacial maximum, and reducedviable habi ta ts for megafauna, and 2)anthropogenic overkill of megafauna ormodificat ion of habitats during ini t ialcolonisation of the continent during the latePleistocene (Martin & Klein, 1984; Diamond,2001, Roberts et al., 2001a; Brook & Bowman,2004; Barnosky et al., 2004; Wroe et al., 2004).While there are numerous examplesdocumenting increasing aridity and less fertilehabitats during the late Pleistocene (Ayliffe et al.,1998; Bowler et al., 2001; Field et al., 2002; Packet al., 2003), there are very few examples linkingearly human artifacts directly to megafauna(Roberts et al., 2001a). One source of confusionhas been that important archaeological sites suchas Lake Mungo and Koonalda Cave have yieldedmeager faunal data. Cuddie Springs, New SouthWales, is the only site in Australia that showsevidence of a dated association between humantechnology and megafauna (Dodson et al., 1993).Fossil bone exhibiting human processing markswere dated to 36-27 ka (Field & Dodson, 1999).However, the association between the artifactsand megafauna remains was questioned byRoberts et al. (2001a) who suggested: 1) thatsediment mixing and re-deposition of bones fromolder to younger units had occurred, and 2) thecut marks on the bones relate to an extant speciesof kangaroo. Although there is little systematicevidence to suggest an anthropogenic component
to Australian megafauna extinction, Flannery(1990) argued that because of the rapid nature ofan overkill ‘blitzkrieg’ extinction, kill sites areunlikely to be found. Additionally, timing thearrival of the first humans and extinction of themegafauna has been impeded by a lack of reliabledates (Baynes, 1999; Diamond, 2001; O’Connell& Allen, 2004). On the Darling Downs, there isno evidence of human occupancy prior to 12ka(Gill, 1978). From sedimentological andecological data, it is evident that increasingaridity on the Darling Downs during the latePleistocene may have led to woodland and vinethicket habitat contraction, and grasslandexpansion on the floodplain. Such habitat changewas likely detrimental to the persistence ofmegafauna species on the Darling Downs duringthe late Pleistocene. However, at present there isno direct evidence to support a hypothesis of ananthropogenic component relating to theretraction of habitats on the Darling Downsbetween the Pleistocene and present.
CONCLUSIONS
Systematic collecting targeting both large andsmall-sized species has facilitated the recovery ofa wide variety of fossil taxa, many previouslyunknown in the Darling Downs fossil record.First Pleistocene Darling Downs records include:pulmonates (7 terrestrial species, 1 aquaticspecies), Tympanocryptis “lineata”, scincids (4species), and Sminthopsis sp. Additionally,several of those new records indicate Pleistocenegeographic range extensions.
It has been assumed that the PleistoceneDarling Downs represents a single local faunawith no faunal regionalisation (Molnar & Kurz,1997). That may appear to be true for largermegafauna taxa, but the small-sized fossil faunasare poorly known at most sites owing to the lackof systematic treatment. Hence, additionalsystematically collected and dated sites arerequired to test the hypothesis proposed byMolnar and Kurz (1997), that the Darling Downsrepresents a single local fauna.
The habitats deduced for the time of depositionof Horizon D appear to be more floristicallycomplex than that of Horizon B. However,analysis of the Pleistocene channel deposits haverevealed several taphonomic biases relating tothe preservation of large- and small-sized taxawithin and between those horizons. Such biaseslimit palaeoenvironmental comparisons betweenthose two units.
DARLING DOWNS PALAEOECOLOGY 195
118
It is evident that there was major habitat changein the Kings Creek floodplain post-deposition ofthe two major fossiliferous horizons atQML1396. That habitat change likely reflectedthe contraction of woodlands, vine thickets andscrublands, and expansion of grasslands on thefloodplain. Sedimentological and ecological datasuggest that that habitat change was climaticallydriven and occurred irrespective of potentialhuman occupation of the region during the latePleistocene.
ACKNOWLEDGMENTS
We thank Gregg Webb, Alex Cook, Liz Reedand Troy Myers for valuable comments anddiscussion on earlier drafts of this manuscript.Bernie Cooke, Scott Hocknull, Liz Reed andBrendan Brooke are thanked for helpfuldiscussions and comments on various aspects ofDarling Downs palaeoenvironments. MatthewNg, Ricky Bell, Philip Colquhon, Luke Shipton,Kristin Spring, Trevor Sutton, Diane and AmySobbe, and Desmond and Jennifer Price,provided much needed support and assistance inthe collection and preparation of fossil material.John Stanisic and Scott Hocknull providedidentifications for the molluscs and agamidsrespectively. The AMS14C dating component ofthe study at ANSTO was supported by grantsfrom AINSE (Grant no’s. 02-013 & 03-123). Thiswork was funded in part by both the QueenslandUniversity of Technology and the QueenslandMuseum.
LITERATURE CITEDANDREWS, P. 1990. Owls, Caves and Fossils. (Natural
History Museum Publications. London).APLIN, K.P. & ARCHER, M. 1987. Recent advances in
marsupial systematics with a new syncreticclassification, Pp. xv-1xxii in M. Archer (ed.),Possums and Opossums: Studies in Evolution.(Surrey, Beatty and Sons and the RoyalZoological Society Society of New South Wales,Sydney).
ARAKEL, A.V. 1982. Genesis of calcrete in Quaternarysoil profiles, Hutt and Leeman Lagoons, WesternAustralia. Journal of Sedimentary Petrology.52(1) 109-125.
ARAKEL, A.V. & MCCONCHIE, D. 1982.Classification and genesis of calcrete and gypsitelithofacies in paleodrainage systems of inlandAustralia and their relationship to carnotitemineralization. Journal of Sedimentary Petrology52(4): 1149-1170.
ARCHER, M. 1976. Phascolarctid origins and thepotential of the selenodont molar in the evolutionof diprotodont marsupials. Memoirs of theQueensland Museum 17(3): 367-371.
1977. Origins and subfamilial relationships ofDiprotodon (Diprotodontidae, Marsupialia).Memoirs of the Queensland Museum 18(1): 37-39.
1978. Quaternary vertebrate faunas from the TexasCaves of southeastern Queensland. Memoirs ofthe Queensland Museum 19(1): 61-109.
1981. Results of the Archbold Expeditions. No.104. Systematic revision of the marsupialdasyurid genus Sminthopsis Thomas. Bulletin ofthe American Museum of Natural History168(2): 61-224.
ARCHER, M., & BARTHOLOMAI, A. 1978. Tertiarymammals of Australia: a synoptic review.Alcheringa 2: 1-19.
ARCHER, M. & HAND, S. 1984. Background to thesearch for Australia’s oldest mammals. Pp. 517-565.In Archer, M. & Clayton, G. (eds), VertebrateZoogeography and Evolution in Australia.(Hesperian Press: Carlisle, Western Australia).
AYLIFFE, L.K., MARIANELLI, P.C., MORIARTY,K.C., WELLS, R.T., MCCOLLUCH, M.T.,MORTIMER, G.E. & HELLSTROM, J.C. 1998.500 ka precipitation record from southeasternAustralia: Evidence for interglacial relativearidity. Geology 26(2): 147-150.
BARNOSKY, A.D., KOCH, P.L., FERANEC, R.S.,WING, S.L. & SHABEL, A.B. 2004. Assessingthe causes of Pleistocene extinctions on thecontinents. Science. 306: 70-75.
BARTHOLOMAI, A. 1967. Troposodon, a new genusof fossil Macropodinae (Marsupialia). Memoirsof the Queensland Museum 15(1): 21-34.
1970. The extinct genus Procoptodon Owen(Marsupialia; Macropodidae) in Queensland.Memoirs of the Queensland Museum 15(4):213-234.
1973. The genus Protemnodon Owen (Marsupialia;Macropodidae) in the upper Cainozoic depositsof Queensland. Memoirs of the QueenslandMuseum 16(3): 309-363.
1975. The genus Macropus Shaw (Marsupialia;Macropodidae) in the upper Cainozoic depositsof Queensland. Memoirs of the QueenslandMuseum 17(2): 195-235.
1976. Notes on the fossiliferous Pleistocenefluviatile deposits of the eastern Darling Downs.Bureau of Mineral Resources, Geology andGeophysics, Bulletin 166: 153-154.
BAYNES, A. 1999. The absolutely last remake of BeauGeste: yet another review of the Australianmegafaunal radiocarbon dates. Records of theWestern Australian Museum, Supplement No. 57:391.
BECK, H.H. 1837. Index Molluscorum Praesentis AeviMusei Principis Augustissimi ChristianiFrederici. Hafniae. Beck Vol. 1 pp. 1-100.
BEESLEY, P.L., ROSS, G.J.B. & WELLS, A. 1998.Mollusca: The Southern Synthesis. Fauna ofAustralia. Vol. 5. (CSIRO Publishing: Melbourne).
BEHRENSMEYER, A.K. 1975. The taphonomy andpaleoecology of Plio-Pleistocene vertebrate
196 MEMOIRS OF THE QUEENSLAND MUSEUM
119
assemblages cast of Lake Rudolf, Kenya. Bulletinof the Museum of Comparative Zoology 146:473-578.
1978. Taphonomic and ecologic information frombone weathering. Paleobiology 4: 150-162.
BELL, H.M. 1973. The ecology of three macropodmarsupial species in an area of open forest andsavannah woodland in north Queensland,Australia. Mammalia 37: 527-544.
BENNETT, G.F. 1876. Notes on rambles in search offossils on the Darling Downs. (GovernmentPrinter: Canberra).
BOIE, F. 1827. Bemerkungen über Merrem’s Versucheines Systems der Amphibien. 1ste Lieferung:Ophidier - Isis, oder Encyclopädische Zeitungvon Oken, 20 (6): columns 508-566.
BONAPARTE, C.L.J.L. 1838. Synopsis vertebratorumsystematis. Nuovi Annali delle Scienze Naturali,Bologna 2(1): 105-133.
BOWLER, J.M., WYRWOLL, K.H. & LU, Y. 2001.Variations of the northwest Australian summermonsoon over the last 300,000 years: thepaleohydrological record of the Gregory (Mulan)Lakes System. Quaternary International 83-85:63-80.
BRITTON, J.C. & MORTON, B. 1982. A dissectionguide, field and laboratory manual for theintroduced bivalve Corbicula fluminea .Malacologia Review Supplement 3:1-82.
BROOK, B.W. & BOWMAN, D.M.J.S. 2002.Explaining the Pleistocene megafaunalextinctions: models, chronologies, andassumptions. Proceedings of the NationalAcademy of Sciences of the United States ofAmerica 99(23): 14624-14627.
2004. The uncertain blitzkrieg of Pleistocenemegafauna. Journal of Biogeography. 31:517-523.
BROT, A. 1874. Die Melaniaceen (Melanidae) inAbbildungen nach der Natur. Pp. 1-32 in Küster,H.C. (ed), Martini, F.W. & Chemnitz, J.H.Systematiches Conchylien-Cabinet. (Bauer &Raspe Bd 1 Abt. 24, Nürnberg).
BROWN, D.S. 1981. Observations of the Planorbinaefrom Australia and New Guinea. Journal of theMalacological Society of Australia 5: 67-80.
CHARPENTIER, J. de. 1837. Catalogue des mollusqueterrestres et fluviatiles de la Suisse. NeueDenkschr. Allg. Schweiz. Ges. Naturw. 1(2): 1-28.
COGGER, H.G. 2000. Reptiles and Amphibians ofAustralia, 6th Edition. (Reed Books, Australia).
CONRAD, R.A. 1850. Descriptions of new species offreshwater shells. Proceedings of the NaturalSciences Philadelphia 5: 10-11.
COVACEVICH, J.A& COUPER, P.J. 1991. The reptilerecords. Pp. 45-140. In Ingram, G.J. & Raven, R.J.(eds), An atlas of Queensland’s frogs, reptiles,birdsandmammals. (QueenslandMuseum:Brisbane).
COVACEVICH, J.A. & EASTON, A. 1974. Rats andmice in Queensland. (Queensland Museum:Brisbane).
CUVIER, G.L.C.F.D. 1837. In Geoffroy (Saint-Hilaire),É. & Cuvier, F. Histoire Naturelle desMammifères, avec figures originales, coloriées,dessinées d’après des animaux vivants. Volumequatrième. Livr. 70. (Blaise, Paris: France).
DALL, W.H. 1903. Contributions to the Tertiary faunaof Florida, with special reference to the Silex bedsof Tampa and the Pliocene beds of theCaloosahatchie River, including in many cases, acomplete revision of the generic groups treatedand their American Tertiary species. Transactionsof the Wagner Free Institute of SciencesPhiladelphia. 3: 1219-1654.
DENNIS, A.J. & JOHNSTON, P.M. 1995. RufousBettong. Pp 285-287. In Strahan, R. (ed.) TheMammals of Australia (New Holland Publishers:Australia).
DESHAYES, G.P. 1830. Encyclopédie Méthodique.Historie naturelle des vers. Paris. Agasse 2: 1-136.
DE VIS, C.W. 1895. A review of the fossil jaws of theMacropodidae in the Queensland Museum.Proceedings of the Linnean Society of New SouthWales 10: 75-133.
DIAMOND, J.M. 2001. Australia’s last giants. Nature411: 755-757.
DIXON, J.M. 1989. Thylacinidae. Pp. 549-559. InWalton, D.W. & Richardson, B.J. (eds.) Fauna ofAustralia. Mammalia Vol. 1B. (AustralianGovernment Publishing Service: Canberra).
DODSON, J., FULLAGAR, R., FURBY, J., JONES, R.& PROSSER, I. 1993. Humans and megafauna ina late Pleistocene environment from CuddieSprings, north western New South Wales.Archaeology in Oceania 28: 94-99.
DODSON, P. 1973. The significance of small bones inpaleoecological interpretation. Contributions toGeology, University of Wyoming 12(1): 15-19.
DUNKER, A.G. 1848. Diagnoses specirum novarumgeneris Planorbis collection is Cumingianae.Proceedings of the Royal Society of London1848: 40-43.
ERICKSON, G. M., DE RICQLÈS, A., DEBUFFRÉNIL, V., MOLNAR, R.E. & BAYLESS,M.A. 2003. Vermiform bones and the evolution ofgigantism in Megalania-how a reptilian foxbecame a lion. Journal of Vertebrate Paleontology23: 966-970.
FENSHAM, R.J. & FAIRFAX, R.J. 1997. The use ofthe land survey record to reconstructpre-European vegetation patterns of the DarlingDowns, Queensland, Australia. Journal ofBiogeography 24: 827-836.
FIELD, J.H. & DODSON, J.R. 1999 Cuddie Springs,New South Wales- revisited. Proceedings of thePrehistorical Society 65: 275.
FIELD, J.H., DODSON, J.R. & PROSSER, I.P. 2002. ALate Pleistocene vegetation history from theAustralian semi-arid zone. Quaternary ScienceReviews 21: 1023-1037.
FIELD, J., & FULLAGER, R. 2001. Archaeology andAustralian Megafauna. Science 294(5540): 7.
DARLING DOWNS PALAEOECOLOGY 197
120
FISCHER, G. 1803. Das Nationalmuseum derNaturgeschichte zu Paris. Von seinem erstenUrsprunge bis zu seinem jetzigen Glanze. ZweiterBand. (Schilderung der naturhistorischenSammlungen. Frankfurt am Main).
FITZINGER, L.J. 1843. Systema Reptilium. Vienna.Braümüller u. Seidel vi.
FLANNERY, T.F. 1990. Pleistocene faunal loss:implications of the aftershock for Australia’s pastand future. Archaeology in Oceania 25(2) 45-55.
FLANNERY, T.F. & ARCHER, M. 1983. Revision ofthe genus Troposodon Bartholomai(Macropodidae: Marsupialia). Alcheringa 7(4):263-279.
FREEDMAN, L. 1967. Skull and tooth variation in thegenus Perameles. Part I: Anatomical features.Records of the Australian Museum 27: 147-166.
FRIEND, J.A. & BURBIDGE, A.A. 1995. Westernbarred bandicoot. Pp 178-180. In Strahan, R. (ed.)The Mammals of Australia. (New HollandPublishers: Australia).
GAFFNEY, E.S. 1981. A review of the fossil turtles ofAustralia. American Museum Novitates 2720:1-38.
GARROD, A.H. 1875. On the kangaroo calledHalmaturus luctuosus by D’Albertis and itsaffinities. Proceedings of the Zoological Societyof London 1875. 48-59.
GEOFFROY (SAINT-HILAIRE), É. 1796.Dissertation sur les animaux à bourse. Mag.Encycl. 3(12): 445-472.
1804. Mémoire sur un nouveau genre demammifères à bourse, nommè Péramèles.Annales de la Musée Natioanl d’ HistoireNaturelle de Paris 4: 56-64.
GILL, E.D. 1978. Geology of the late Pleistocene Talgaicranium from S. E. Queensland, Australia.Archaeology and Physical Anthropology inOceania 13: 177-197.
GILL, T. 1872. Arrangement of the families ofmammals with analytical table. SmithsonianMiscellaneous Collection 2: I-VI, 1-98.
GLASBY, C. J., ROSS, G.J.B. & BEESLEY, P.L. 1993.Fauna of Australia. Vol. 2AAmphibia and reptilia.Viii 439pp. (Australian Government PublishingService: Canberra).
GLAUERT, L. 1926. Alist of Western Australian fossil.Supplement No. 1. Bulletin of the GeologicalSurvey of Western Australia 88: 36-77.
GOLDFUSS, G.A. 1820. Handbuch der Zoologie. J. L.Schrag, Nürnberg.
GRAY, J.E. 1821. On the natural arrangement ofvertebrose animals. London Medical Repository15(1): 296-310.
GRAY, J.E. 1825a. A synopsis of the genera of reptilesand Amphibia, with a description of some newspecies. Annals of Philosophy 10: 193-217.
GRAY, J.E. 1825b. Outline of an attempt at thedisposition of the Mammalia into tribes andfamilies with a list of the genera apparently
appertaining to each tribe. Annals of Philosophy10(2): 337-344.
1832. Characters of a new genus of Mammalia, andof a new genus and two new species of lizards,from New Holland. Proceedings of theZoological Society of London 1832: 39-40.
1847. A list of the genera of recent Mollusca, theirsynonyma and types. Proceedings of theZoological Society of London 15: 129-219.
GREER, A.E. 1979. A phylogenetic subdivision ofAustralian skinks. Records of the AustralianMuseum 32: 339-371.
1989. The biology and evolution of australianlizards. (Surrey, Beatty and Sons: ChippingNorton).
GÜNTHER, A. 1858. Catalogue of the BatrachiaSalientia in the collection of the British Museum.(British Museum: London).
HARDWICKE, M.G. & J.E. GRAY. 1827. A Synopsisof the Species of Saurian Reptiles, collected inIndia by Major-General Hardwicke. ZoologicalJournal (London) 3: 213-229.
HARRIS, G.P. 1808. Description of two new species ofDidelphis from Van Diemens’s Land.Transactions of the Linnean Society of London 9:174-178.
HECHT, M. 1975. The morphology and relationships ofthe largest known terrestrial lizard, Megalaniaprisca Owen, from the Pleistocene of Australia.Proceedings of the Royal Society of Victoria 87:239-250.
HEDLEY, C. 1924. Some notes on Australian shells.Australian Zoology 3: 215-222.
HOCKNULL, S.A. 2002. Comparative maxillary anddentary morphology of the Australian dragons(Agamidae: Squamata): A framework for fossilidentification. Memoirs of the QueenslandMuseum 48(1): 125-145.
HUTCHINSON, M.N. 1993. Family Scincidae. Pp261-279. In Glasby, C.J., Ross, G.J.B. & Beesley,P.L. (eds.) Fauna of Australia. Vol. 2a Amphibiaand Reptilia. (Australian Publishing Service,Canberra).
HUTTON, F.W. 1884. Revision of the land Mollusca ofNew Zealand. Transactions of the New ZealandInstitute XVI: 186-212.
HUXLEY, T.H. 1880. On the Application of the laws ofevolution to the arrangement of the Vertebrata,and more particularly of the Mammalia.Proceedings of the Zoological Society of London649-662.
ILLIGER, C. 1811. Prodromus systematis mammaliumet avium additis terminus zoographics utriudqueclassis. (C. Salfeld, Berlin) I-xviii, 1-301.
INGRAM, G.J. & LONGMORE, N.W. 1991. The frogrecords. Pp. 16-44. In Ingram, G.J. & Raven, R.J.(eds), An atlas of Queensland’s frogs, reptiles,birds and mammals. (Queensland Museum:Brisbane).
198 MEMOIRS OF THE QUEENSLAND MUSEUM
121
IREDALE, T. 1933. Systematic notes on Australianland shells. Records of the Australian Museum19: 37-59.
1934. The freshwater mussels of Australia.Australian Zoologist. 8: 57-58.
1937. A basic list of the land Mollusca of Australia.Australian Zoologist. 8: 237-333.
JOHNSON, C.N & PRIDEAUX, G.J. 2004. Extinctionsof herbivorous mammals in the late Pleistocene ofAustralia in relation to their feeding ecology: noevidence for environmental change as cause ofextinction. Austral Ecology. 29: 553-557.
JONES, B. & BAYNES, A. 1989. Illustrated keys toAustralian Mammalia to generic level. Pp.1075-1171, In Walton, D.W. & Richardson, B.J.(eds) Fauna of Australia. Mammalia Vol. 1B..Canberra. (Australian Government PublishingService: Canberra)
JONES, M. 1995. Tasmanian devil. Pp. 82-84, InStrahan, R. (ed.) The mammals of Australia. (NewHolland Publishers: Australia).
KEAR, B.P., HAMILTON-BRUCE, R.J., SMITH, B.J.& GOWLETT-HOLMES, K.L. 2003.Reassessment of Australia’s oldest freshwatersnail, Viviparus (?) albascopularis Etheridge,1902 (Mollusca: Gastropoda: Viviparidae), fromthe Lower Cretaceous (Aptian, WallumbillaFormation) of White Cliffs, New South Wales.Molluscan Research 23: 149-158.
KNOX, E. 1976. Upper molar alveolar patterns of somemuridae in Queensland and Papua New Guinea.Memoirs of the Queensland Museum. 17:457-459.
KOS, A.M. 2003. Characterisation of post-depositionaltaphonomic processes in the accumulation ofmammals in a pitfall cave deposit fromsoutheastern Australia. Journal of ArchaeologicalScience 30: 781-796.
LAMB, J. 1911. Description of three new batrachiansfrom southern Queensland. Annals of theQueensland Museum 10: 26-28.
LAMPRELL, K. & HEALY, J. 1998. Bivalves ofAustralia. (Backhuys Publishers: Leiden).
LAWSON, E.M., ELLIOT, G., FALLON, J., FINK, D.,HOTCHKIS, M.A.C., HUA, Q., JACOBSEN,G.E., LEE, P., SMITH, A.M., TUNIZ, C. &ZOPPI, U. 2000. AMS at ANTARES- the first 10years. Nuclear Instruments and Methods inPhysics Research Section B: Beam interactionswith Materials and Atoms 172: 95-99.
LONG, J. & MACKNESS, B. 1994. Studies of the lateCainozoic diprotodontid marsupials of Australia.4. The Bacchus Marsh diprotodons- Geology,sedimentology and taphonomy. Records of theSouth Australia Museum 27(2): 95-110.
LUCKETT, W.P. 1993. An ontogenetic assessment ofdental homologies in therian mammals. Pp.182-204 in Szalay, F.S., Novacek, M.J. &McKenna, M.C. (eds) Mammal phylogeny,Volume 1. (Springer-Verlag: New York).
LUDBROOK, N.H. 1978. Quaternary molluscs of thewestern part of the Eucla Basin. Bulletin of theGeological Survey of Western Australia 125:1-286.
1984. Quaternary molluscs of South Australia.Department of South Australia. Department ofMines and Energy, South Australia. Handbookno. 9.
LUNDELIUS, E.L. Jr. 1989. The implications ofdisharmonious assemblages for Pleistoceneextinctions. Journal of Archaeological Science.16: 407-417.
LYDEKKER, R. 1888. Catalogue of fossil reptilia andamphibia in the British Museum (NaturalHistory). Part 1.
MACINTOSH, N.W.G., 1967. Fossil man in Australia.Australian Journal of Science 30: 86-98.
MARTENS, E.C. von. 1861. Nachträge. Pp. 174. InAlbers, J.C. (ed.) Die Heliceen, nach natürlicherVerwandtshaft systematisch geordnet. 2. Ausgabeherausgegeben von E. von Martens. (WilhelmEngelman: Leipzig).
MARTIN, P.S. & KLEIN, R.G. (Eds.) 1984. QuaternaryExtinctions: A Prehistoric Revolution.(University of Arizona Press: Tucson).
MCMICHAEL, D.F. 1968. Non-marine Mollusca fromTertiary rocks in northern Australia. Bulletin ofthe Bureau of Mineral Resources, Geology andGeophysics, Australia 80: 133-157.
MERREM, B. 1820. Versuch eines Sytems Amphibien.Tentamen systematis Amphibiorum. (Krieger:Marburg).
MOLNAR, R.E. 1990. New cranial elements of a giantvaranid from Queensland. Memoirs of theQueensland Museum 29: 437-444.
MOLNAR, R.E., & KURZ, C. 1997. The distribution ofPleistocene vertebrates on the eastern DarlingDowns, based on the Queensland Museumcollections. Proceedings of the Linnean Society ofNew South Wales 117: 107-133.
MOORE, J.A. 1958. A genus and species ofleptodactylid frog from Australia. AmericanMuseum Novitates 1919: 1-7.
MÜLLER, J. 1846. On the structure and characters ofthe ganoidei, and the natural classification of fish.Scientific Memoirs 4: 499-552.
MÜHLFELD, J.K.M. von. 1846. Entwurf eines neuensystem’s der schaltiergeha..se. Magazine Ges.Naturf. Freunde Berline. 5: 38-72.
MURRAY, P.F. 1984. Extinctions downunder: Abestiary of extinct Australian Late Pleistocenemonotremes and marsupials. Pp. 600-628. InMartin, P. S. & Klein, R. G. (eds.), Quaternaryextinctions. (The University of Arizona Press:Tuscon).
O’CONNELL, J.F. & ALLEN, J. 2004. Dating thecolonization of Sahul (Pleistocene Australia–NewGuinea): a review of recent research. Journal ofArchaeological Science 31: 835–853.
ORTMANN, A.E. 1910. A new system of theUnionidae. Nautilis 23: 114-120.
DARLING DOWNS PALAEOECOLOGY 199
122
QUOY, J.R.C. & GAIMARD, J.P. 1824. Volage del’Uranie- Zoologie: 56. In Voyage Autor duMonde. Freycinet, L. D. Chez (ed.), Pillet Aine,Imprimeur-Libraire: Paris
OWEN, R. 1838. Fossil mammal remains fromWellington Valley, Australia. Marsupialia. Pp.359-369, Appendix to Mitchell, T. L. Threeexpeditions into the interior of eastern Australia,with descriptions of the recently explored regionof Australia Felix, and of the present colony ofNew South Wales. (T. & W. Boone: London). 2.
1858. Odontology. Teeth of mammals .Encyclopedia Britannica, or dictionary of arts,sciences, and general literature, 8th edition.
1860. Description of some remains of a giganticland-lizard (Megalania prisca) from Australia.Philosophical Transactions of the Royal Society1860: 45-46.
1874. On the fossil mammals of Australia, partVIII. Family Macropodidae: genera Macropus,Osphranter, Phascolagus, Sthenurus andProtemnodon. Philosophical Transactions of theRoyal Society 164: 245-287.
1877a. Researches on the fossil remains of theextinct mammals of Australia; with a notice ofthe extinct marsupials of England. (J. Erxlebe:,England).
1877b. On a new species of Sthenurus, withremarks on the relation of the genus to Dorcopsis,Müller. Proceedings of the Scientific Meetings ofthe Zoological Society of London 1877:352-361.
PACK, S.M., MILLER, G.H., FOGEL, M.L. &SPOONER, N.A. 2003. Carbon isotopic evidencefor increased aridity in northwestern Australiathrough the Quaternary. Quaternary ScienceReviews 22: 629-643.
PETERS, W., 1863. Übersicht der von Hrn. RichardSchomburgkan das zoologishe museumeingesandten Amphibien, aus Buchstelde beiAdelaide in Südaustralien. Monatsberichte derköniglichen preussichen Akademie derWissenshaftenzu Berlin 1863: 228-236
PFEIFFER, L. 1845. Descriptions of twenty-two newspecies of Helix, from the collections of MissSaul, Mr Walton Esq., and H. Cuming, Esq.Proceedings of the Zoological Society of London1845: 71-75.
PHILIPPI, R.A. 1847. Abbildungen undBeschriebungen neuer oder wenig gekannterConchylien. Cassel. theodor Fischer 3: 1-50.
PILSBRY, H.A. 1895. In Tryon, G.W. & Pilsbry, H.A.Manual of Conchology. Conchological Section,Academy of Natural Sciences Philadelphia.Series 2 Vol. 8.
PLEDGE, N.S. 1990. The upper fossil fauna of theHenshke Fossil Cave, Naracoorte, SouthAustralia. Memoirs of the Queensland Museum28(1) 247-262.
PRICE, G.J. 2002. Perameles sobbei sp. nov.(Marsupialia, Peramelidae), a Pleistocene
bandicoot from the Darling Downs, south-easternQueensland. Memoirs of the QueenslandMuseum 48(1): 193-197.
2004. Fossi l bandicoots (Marsupial ia ,Peramelidae) and environmental change duringthe Pleistocene on the Darling Downs,southeastern Queensland, Australia. Journal ofSystematic Palaeontology 2: 347-356.
PRICE, G.J., TYLER, M.J. & COOKE, B.N. in press.Pleistocene frogs from the Darling Downs,southeastern Queensland, Australia, and theirpalaeoenvironmental significance. Alcheringa.
PRIDEAUX, G.J. 2004. Systematics and evolution ofthe Sthenurine kangaroos. University ofCalifornia Publications in Geological Sciences146: 1-623.
QUOY, J.R.C. & GAIMARD, J.P. 1824. Zoologie: P.56, in Voyage autour du Monde. Freycinet, L.C.,de (ed.), Pillet Ainé, Imprimeur-Libraire: Paris.
RAFINESQUE, C.S. 1815. Analyse de la Nature, ouTableau de l’Univers et des Corps Organises.Palermo.
RAPSON, D.J. 1990. Pattern and process in intra-sitespatial analysis: site structural and faunal researchat the Bugas-Holding Site. PhD dissertation,University of New Mexico, Albuquerque.(University Microfilms International: Ann Arbor).
RIDE, W.D.L. 1964. A review of Australian fossilmarsupials. Journal of the Royal Society ofWestern Australia 47: 97-131.
RIDE, W.D.L. & DAVIS, A.C. 1997. Origins andsetting: mammal Quaternary palaeontology in theEastern Highlands of New South Wales 117:197-222.
ROBERTS, R.G., FLANNERY, T.F., AYLIFFE, L.K.,YOSHIDA, H., OLLEY, J.M., PRIDEAUX, G.J.,LASLETT, G.M., BAYNES, A., SMITH, M.A.,JONES, R. & SMITH, B.L. 2001a. New ages forthe last Australian megafauna: Continent-wideextinction about 46,000 years ago. Science292(5523): 1888-1892.
2001b. Archaeology and Australian megafauna:response. Science 194(5540): 7.
SCHLEGEL, H. 1850. Description of a new genus ofbatrachians from Swann River. Proceedings of theLinnean Society of London 18: 9-10.
SHEA, G.M. 1990. The genera Tiliqua andCyclodomorphus (Lacertilia: Scincidae): genericdiagnoses and systematic relationships. Memoirsof the Queensland Museum 29: 495-520.
SHELDON, F. & WALKER, K.F. 1989. Effects ofhypoxia on oxygen consumption by two speciesof freshwater mussel (Unionacea: Hyriidae) fromthe River Murray (Australia). Australian Journalof Marine and Freshwater Research 40(5):491-500.
SMITH, B.J. & KERSHAW, R.C. 1979. Field guide tothe non-marine molluscs of south-easternAustralia. (A.N.U. Press: Canberra).
SMITH, M.J. 1972. Small fossil vertebrates fromVictoria Cave, Naracoorte, South Australia. II.
200 MEMOIRS OF THE QUEENSLAND MUSEUM
123
Peramelidae, Thylacindae and Dasyuridae(Marsupialia). Transactions of the Royal Societyof South Australia 96: 125-137.
1976. Small fossil vertebrates from Victoria Cave,Naracoorte, South Australia. IV. Reptiles.Transactions of the Royal Society of SouthAustralia 100: 39-51.
SOBBE, I.H. 1990. Devils on the Darling Downs- thetooth mark record. Memoirs of the QueenslandMuseum 27(2): 299-322.
SOLEM, A. 1979. Camaenid land snails from westernand central Australia (Mollusca: Pulmonata:Camaenidae) I. Taxa with trans-Australiandistribution. Records of Western AustralianMuseum Supplement 10: 5-142
1993. Camaenid land snails from western andcentral Australia (Mollusca: Pulmonata:Camaenidae). VI. Taxa from the red centre.Records of the Western Australian Museum,Supplement 43: 983-1459.
STANISIC, J. 1990. Systematics and biogeography ofeastern Australian Charopidae (Mollusca,Pulmonata) from subtropical rainforests.Memoirs of the Queensland Museum 30: 1-241.
STRAHAN, R. 1995. The mammals of Australia. (NewHolland Publishers: Australia).
STODDART, E. 1995. Long-nosed bandicoot. pp.184-185. in Strahan, R. (ed.) The Mammals ofAustralia. (New Holland Publishers, Australia).
STUIVER, M. & POLACH, A. 1977. Reporting of 14Cdata. Radiocarbon 19(3): 355-363.
TATE, G.H.H. 1948. Studies on the anatomy andphylogeny of the Macropodidae (Marsupialia).Results of the Archbold Expeditions, No. 59.Bulletin of the American Museum of NaturalHistory 91: 237-351.
TEMMINCK, C.J. 1824. Sur le genre Sarigue-Didelphis (Linn.) and Sur les mammifères dugenre Dasyure, et sur deux genres voisins, lesThylacynes et les Phascologales. Pp. 21-54 &55-72, in Temmnick C.J. 1814-1827.Monographies de Mammalogie, ou description dequelques genres de mammifères dont les espècesont été observées dabs les différens musées del’Europe. Ouvrage accinoagné de planchesd’Ostéologie, pouvant server de suite et decomplément aux notices sur les animaux vivans,publiées par M. le Baron G. Cuvier, dansrecherches sur les ossemens fossils. (G. Dufour etE. D’Ocagne Tom.: Paris).
THOMAS, O. 1887. On the specimens of Phascologalein the Museo Cicica, Genoa, with notes on theallied species of the genus. Annali del MuseoCivico di Storia Naturale di Genova 4: 502-511.
TROSCHEL, F. H. 1856-63. Das Gebiß der Schneckenzur Begründung einer natürlichen Classifikation.Nicolaische Verlagsbuchhandlung Berlin 1:1-252.
TRUEB, L. 1973. Evolutionary biology of anurans. InVial, J.L. (ed.), Contemporary research on major
problems. (University of Missouri Press:Columbia).
TYLER, M.J. 1976. Comparative osteology of thepelvic girdle of Australian frogs and description ofa new fossil genus. Transactions of the RoyalSociety of South Australia.
1990. Limnodynastes Fitzinger (Anura:Leptodactylidae) from the Cainozoic ofQueensland. Memoirs of the QueenslandMuseum 28(2): 779-784.
1991. Kyarranus Moore (Anura, Leptodactylidae)from the Cainozoic of Queensland. Proceedingsof the Royal Society of Victoria103(1): 47-51.
VAN DYCK, S.M. & LONGMORE, N.W. 1991. Themammals records. Pp. 284-336, In Ingram, G.J. &Raven, R.J. (eds.), An Atlas of Queensland’sFrogs, Reptiles, Birds and Mammals. (Board ofTrustees of the Queensland Museum, Brisbane).
VOORHIES, M.R. 1969. Taphonomy and populationdynamics of an early Pliocene vertebrate fauna,Knox County, Nebraska. Contributions toGeology, University of Wyoming Special paperNo. 1: 1-69.
WATERHOUSE, G.R. 1838. Catalogue of theMammalia Preserved in the Museum of theZoological Society. 2nd Edition. (Richard & JohnTaylor: London).
WELLS, R.T., HORTON, D.R. & ROGERS, P. 1982.Thylacoleo carnifex Owen (Thylacoleonidae):marsupial carnivore? Pp. 573-586. In Archer, M.(ed.) Carnivorous Marsupials. Vol. 2. (SurreyBeatty & Sons: Chipping Norton).
WENTWORTH, C.K. 1922. A scale of grade and classterms for clastic sediments. Journal of Geology30: 377-392.
WILKINSON, J. 1995. Fossil record of a varanid fromthe Darling Downs, southeastern Queensland.Memoirs of the Queensland Museum 38: 92.
WITHERS, P.C. & O’SHEA, J.E. 1993. Morphologyand Physiology of the Squamata. Pp 172-196. InGlasby, C.J., Ross, G.J.B. & Beesley, P.L. (eds).Fauna of Australia. Vol 2A Amphibia and reptilia.(Australian Government Publishing Service:Canberra).
WOODS, J.T. 1960. Fossiliferous fluviatile and cavedeposits. Pp. 393-403. In Hill, D. & DenmeadA.K. (eds) The Geology of Queensland. Journal ofthe Geological Society of Queensland.
WROE, S., FIELD, J., FULLAGAR, R., & JERMIIN,L. 2004. Late Quaternary extinctions ofmegafauna and the global overkill hypothesis.Alcheringa 28: 291-331.
WROE, S., MYERS, T.J. , WELLS, R.T. &GILLESPIE, A. 1999. Estimating the weight ofthe Pleistocene marsupial lion, Thylacoleocarnifex (Thylacoleonidae : Marsupialia):implications for the ecomorphology of amarsupial super-predator and hypotheses ofimpoverishment of Australian marsupialcarnivore faunas. Australian Journal of Zoology47: 489-498.
DARLING DOWNS PALAEOECOLOGY 201
124
Paper 4. PRICE, G.J. & WEBB, G.E. in press. Late Pleistocene sedimentology,
taphonomy and megafauna extinction on the Darling Downs, southeastern
Queensland, Australia. Australian Journal of Earth Sciences.
This chapter presents a comprehensive stratigraphic, sedimentologic, and
taphonomic analysis of a late Pleistocene Darling Downs fossil deposit at site
QML796. Those investigations allowed additional development of
hypotheses relating to Darling Downs megafaunal extinction. This chapter
represents a preprint of an article submitted for consideration in Australian
Journal of Earth Sciences (2005 © Geological Society of Australia).
Australian Journal of Earth Sciences is available online at:
http://journalsonline.tandf.co.uk/openurl.asp?genre=journal&issn=0812-0099.
Contribution of authors
I collected, prepared and identified most of the material that was examined in
this paper (with additional support from others noted in the
Acknowledgements). I also supervised that laboring efforts of the volunteers
who assisted in the preparation of fossil material. I measured stratigraphic
sections, collected sediment samples, and carried out grain size analyses.
Additionally, I conducted all subsequent taphonomic analyses and prepared
the original and final manuscripts for submission.
Gregory E. Webb guided the sedimentological analyses and assisted in
the development of ideas and interpretation of the deposits. His role in
manuscript preparation was primarily editorial.
125
Late Pleistocene sedimentology, taphonomy and megafauna extinction on
the Darling Downs, southeastern Queensland, Australia
Gilbert J. Price and Gregory E. Webb
School of Natural Resource Sciences, Queensland University of Technology,
GPO Box 2434, Brisbane, Queensland, Australia 4001
Phone: (07) 3406 8350
Mobile: 0439 876 005
Fax: (07) 3406 8355
Suggested running title: Darling Downs megafauna deposits
126
ABSTRACT
The Kings Creek catchment, southeastern Queensland, contains a variety of
Pleistocene-Holocene depositional settings. Fluvial depositional accumulation
processes in the catchment reflect both high-energy channel and low-energy
episodic overbank deposition. The lithofacies and depositional environments of
locality QML796 were examined in detail to aid interpretation of taphonomic
accumulation patterns of large and small taxa in the deposit. The basal
fossiliferous unit was deposited in a meandering channel and passes upward
into overbank deposits that include ephemeral interfluve channels and splays.
The most striking taphonomic observations for vertebrates at the locality
include: 1) low representation of post-cranial elements; 2) high degree of bone
breakage; 3) variable abrasion but most identifiable bone elements with low to
moderate degree of abrasion; 4) low rates of bone weathering; and 5) low
degree of articulated or associated specimens. Collectively, those data suggest
that the material was transported into the deposit from the surrounding proximal
floodplain and that the assemblages reflect substantial hydraulic sorting.
However, despite that, sequential faunal horizons show a step-wise decrease in
taxonomic diversity that cannot be explained by sampling or taphonomic bias.
The decreasing diversity includes loss of some, but not all, megafauna and is
consistent with a progressive local loss of megafauna in the catchment over an
extended interval of time. Data are consistent with a climate change model for
megafauna extinction but not with nearly simultaneous extinction of megafauna
as required by the human-induced blitzkrieg extinction hypothesis.
Key words: fluvial sedimentology, taphonomy, Darling Downs,
Queensland, Australia, megafauna extinction, Pleistocene.
INTRODUCTION
Our understanding of current threats to biodiversity and the prospects for
survival of extant species is informed by palaeoecology, and in particular,
knowledge of previous extinction events. Although mass extinction events have
been documented throughout the Phanerozoic, one of the most relevant, but
127
least well understood, intervals of species loss occurred near the end of the
Pleistocene, i.e., the extinction of terrestrial megafauna.
The late Cainozoic witnessed the evolution and subsequent extinction of
some of the largest land animals (lizards, birds and mammals) that the world
has known. In Australia, 88 % of Pleistocene terrestrial taxa with average
weights in excess of 44 kg became extinct before the end of the epoch
(Barnosky et al., 2004). Causes for extinction have been debated widely with
climate change, human hunting and/or agricultural practise, or a combination of
those factors being the dominant hypotheses (for recent reviews see Horton,
2000; Barnosky et al., 2004; Wroe et al., 2004; Burney & Flannery, 2005).
Testing such hypotheses has proven difficult, and in Australia in particular, the
lack of a spatially constrained chronology for the extinction of individual species
and for human occupation renders many hypotheses almost impossible to test.
Roberts et al. (2001) suggested that the last Australian megafauna occurred at
~46.4 ka, but their sampling procedures and subsequent interpretations have
been strongly criticised (Field & Fullager 2001; Wroe et al., 2004). Aside from
the fact that the 46.4 ka date falls near the limit of effective radiocarbon dating
(Gillespie, 2002), Roberts et al. (2001) analysed only deposits that contain
articulated remains of megafauna. Although the sampling strategy was aimed at
limiting the possibility of reworking of older megafaunal remains into younger
deposits, it automatically excludes the majority of known late Pleistocene
megafauna sites, including, for example, most archaeological sites (e.g., Field &
Fullagar, 2001). Many such sites have been dated younger than 46.4 ka (e.g.,
Cuddie Springs; Field & Dodson, 1999; Roberts et al., 2001; Trueman et al.,
2005). The stratigraphic integrity and provenance of fossils from younger
deposits may be questioned (Baynes, 1999), but reworking cannot be assessed
on the basis of dating alone (Field & Fullagar, 2001; Trueman et al., 2005).
Specific hypotheses of reworking can be tested by using data from disciplines
such as taphonomy, sedimentology, geochemistry, archaeology and
geomorphology, to independently establish the context and accumulation
128
processes of a fossil deposit (e.g., Behrensmeyer, 1988; Lyman 1994; Trueman
et al., 2005).
Unfortunately, few studies have specifically investigated the depositional
processes and taphonomic modes of fossil accumulation of Australian
megafauna deposits (e.g., Baird, 1991; Long & Mackness, 1994; Van Huet,
1999; Brown & Wells, 2000). Hence, spatial and temporal constraints on the
palaeoecology of prehistoric Australian terrestrial communities are poorly
known, especially including those that encompass late Pleistocene megafauna
extinction. Studies that document taphonomic modes of bone accumulation are
particularly relevant in that they can aid recognition of reworking and bias
related to both accumulation processes and preservation. Bias in the fossil
record may affect diversity estimates, timing of extinction events, and analysis of
palaeobiological and palaeoenvironmental parameters (Behrensmeyer, 1988;
Lofgren et al., 1990). Many processes influence the progression of bones from
the living animal to their final place of burial and preservation, including activity
by carnivores, pre-burial weathering, hydraulic transport and abrasion,
diagenesis, and the accumulation mode itself (i.e., processes that cause sorting
in specific depositional environments) (Voorhies, 1969, Dodson, 1971; 1973;
Behrensmeyer, 1975; 1978; 1982; 1988; Haynes, 1980; 1983; Andrews, 1990;
Lyman, 1994). Hence, taphonomic processes must be considered in order to
constrain palaeoecological inferences based on fossil assemblages.
Vertebrate accumulations from deposits such as those in caves are generally
considered to be of high value for interpreting past environmental conditions
because remains typically are not transported far or reworked and mixed
vertically (Andrews, 1990; Baird, 1991). However, more abundant deposits from
fluvial depositional environments commonly have much more complicated
depositional histories, both temporally and spatially. Hence, fluvial environments
hold greater possibilities for mixing local faunas with contemporaneous faunas
transported from distant environments or with older fossils reworked from
eroding deposits (Behrensmeyer, 1988). However, faunal associations from
129
such deposits are capable of yielding useful information on past environmental
conditions provided they are carefully documented and analysed.
Some of the youngest known Australian Pleistocene megafaunal remains
have been recovered from fluvial deposits in the Kings Creek catchment in the
Clifton region of the Darling Downs, Australia (Roberts et al., 2001). Late
Pleistocene vertebrate remains from the Kings Creek area range from
articulated skeletons to disarticulated and highly fragmented, abraded remains
and occur in low-energy overbank deposits at QML783 (Molnar et al., 1999) and
in high-energy channel deposits and lower-energy, episodic overbank deposits
at site QML1396 (Price & Sobbe, 2005). Importantly, the Pleistocene catchment
size is constrained by regional drainage divides and was very small in area
(Price, 2005), probably not much larger than the present catchment (~500 km2)
(Figure 1). Thus, faunal remains represent local Pleistocene environmental
conditions. Price and Sobbe (2005) described the depositional environment of
the vertebrate-bearing site QML1396 (Figure 1) and concluded that a lower
fossiliferous horizon was deposited as a high-energy channel fill, whereas a
higher horizon was deposited in an overbank setting as crevasse splay
deposits. The ecologies of the faunal assemblages from the two horizons
suggested that woodland and vine-thicket habitats contracted as open
grasslands expanded between deposition and European arrival in the region.
Radiocarbon dating of the horizons yielded dates of 44.3-49.9 ka (Price &
Sobbe, 2005), near the limits of effective dating. Interestingly, the lower channel
deposits contain diverse megafaunal remains, whereas megafaunal diversity is
greatly reduced in the upper horizon. Unfortunately, it could not be determined if
the rarity of megafauna in the upper horizon was due to local extinction or to a
bias in accumulation due to differential sorting during deposition of the overbank
deposits (Price & Sobbe, 2005). Regardless, the site shows evidence of
changing faunal composition, which may reflect changing habitat, between the
two horizons, and megafauna clearly became extinct some time subsequent to
deposition of the upper fossiliferous horizon.
130
Figure 1. Modern Kings Creek Catchment with heights (metres) of surrounding peaks, the main
study locality (site QML796), and other localities mentioned in the text (GDR: Great Dividing
Range; KCC: Kings Creek Catchment; QML: Queensland Museum Locality).
The purpose of this paper is to describe the sedimentology and taphonomy of
vertebrate remains from site QML796, located in the northern bank of Kings
Creek, ~200 m downstream from site QML1396. Fossil remains at site QML796
include more than sixty species ranging in size from small invertebrates to
megafauna (e.g., Diprotodon sp.) and occur in at least three highly fossiliferous
horizons, at least one of which appears to be younger than both fossiliferous
horizons studied at site QML1396. Thus, the site can provide data to test the
hypothesis that megafauna became extinct in a single event in the Kings Creek
catchment. Site QML796 was excavated from the top down so as to record
stratigraphic data and bone orientation, and >24 m3 of sediment were sieved to
recover both large and small remains. The small catchment size combined with
detailed excavation and sieving techniques provides an opportunity to
investigate sedimentologic and taphonomic controls on the accumulation of
remains of large- and small-sized taxa from in situ stratigraphic horizons that
131
could bracket the extinction of some megafauna on the Darling Downs. Such
analyses are crucial for interpreting fossil-based palaeoecological information,
thereby providing data for testing specific hypotheses about the causes of
megafaunal extinction in Australia.
SETTING
The Darling Downs, southeastern Queensland, Australia, encompasses the low
rolling hills and plains west of the Great Dividing Range (Figure 1). Site QML796
(Figure 1) was discovered on the northern bank of Kings Creek by Mr. Ian
Sobbe of Clifton in the early 1980s. The initial exposure was ~6-7 m in diameter
with a 2.3 m-thick fossil bearing horizon. The modern Kings Creek catchment is
fed from the east by shallow, ephemeral watercourses, and is bounded to the
north, east and south by the topographically high Great Dividing Range (Figure
1). On the basis of regional topographic constraints, Price (2005) suggested that
Pleistocene fossil material deposited in the catchment is unlikely to have been
sourced from geographic areas outside the modern catchment (i.e., from
distances greater than 20-25km to the east). Early collecting at site QML796
was sporadic, generally focusing on recovery of larger megafaunal taxa.
Systematic collecting of the deposit by the Queensland Museum (QM)
commenced in 2000, and a diverse small-sized fauna was recovered (Price
2002, Price et al., 2005). More recently, joint excavations by the Queensland
University of Technology (QUT) and QM have focused on the collection of
stratigraphic, sedimentologic, and taphonomic data from the deposit.
The poorly indurated sediments of the Darling Downs consist of clay, silt and
sand derived from the erosion of underlying Mesozoic sandstone and Tertiary
basalt (Woods, 1960; Gill, 1978); previous stratigraphic studies were described
by Price and Sobbe (2005). The exact age of Darling Downs fossil deposits is
poorly constrained. Gill (1978) dated fossiliferous deposits near Talgai,
Queeensland using radiocarbon techniques and obtained dates of 41.5-23.6 ka
for charcoal, 20.17-6.45 ka for molluscs, and 30.8-4.42 ka for carbonate
nodules. Price (2005), Price and Sobbe (2005), and Price et al. (2005) reported
132
accelerator mass spectrometry (AMS) radiocarbon dates from charcoal and
fossil bivalves for QML796 and QML1396 of 49.9-40 ka. Roberts et al. (2001)
dated site QML783 (= ‘Ned’s Gully’; Figure 1) to ~47 ka based on optically-
stimulated luminescence (OSL). Hence, deposits in Kings Creek are most likely
late Pleistocene.
METHODS
Excavation and Sedimentology
The early QM excavation involved the documentation of seven main
stratigraphic units (designated A1 to A7) from top to bottom. Fossils were
recovered from an exposed vertical section by in-situ collecting and removal of
bulk sediment to target smaller specimens. All fossil material was labelled
according to the sedimentary horizon from which it was derived, and >10 m3 of
sediment were processed.
More recent QUT-QM excavations involved a ‘top down’ excavation
approach. A 3x2 m plot was surveyed on the ground above the site, and 1x1 m
quadrats were excavated in 10 cm increments using trowels and brushes.
Excavated layers were correlated to stratigraphic units on the vertical sides of
the pit. The excavation continued to the depth of 2.3 m yielding an additional
~14 m3 of material. Orientations of freshwater bivalves (Velesunio ambiguus)
and bones larger than 2 cm were recorded in-situ. The attitude (i.e., concave- or
convex-up) of V. ambiguus valves was also documented. Excavated sediment
was washed using graded sieves (10 and 1mm), and small bones were sorted
following techniques described by Andrews (1990). The manual sieving and
sorting was particularly labour intensive, with museum volunteers contributing
>15 000 hours of labour.
The entire exposed section was measured and documented on vertical
surfaces during excavation. Sediment samples from each stratigraphic unit were
disaggregated using alternating cycles of bleach and detergent, dried, and
sieved using –2 to 4 phi mesh sizes for grain size analysis. A 2.3 metre-long
auger was used to probe surrounding sediment to determine the lateral extent
133
of particular beds. Lithofacies and fluvial architectural elements were identified
and assigned facies codes following the technique described by Miall (1996).
Taphonomic Analysis
Identifiable cranial and post-cranial material of terrestrial vertebrate species
provided the basis for the taphonomic study. Unidentifiable bone fragments
were not used. The unit of element representation includes MNI (minimum
number of individuals; equivalent to NISP [number of identified specimens]
following Badgely, 1986), and MNE (minimum number of elements; Lyman,
1994). For vertebrates, identification of taxa was based mostly on dentary and
maxillary remains, except in the case of fish, frogs, turtles and some
squamates, where vertebrae, pelves, carapace/plastron fragments and
osteoderms were used, respectively. We conducted rarefaction analyses using
the PAST © statistical software (Hammer et al., 2001) on taxon abundance data
for each assemblage to test for potential bias introduced by differences in
sample sizes. Diversity patterns using the rarifed data sets were compared
between assemblages of standardised subsample sizes with independent
Kolmogorov-Smirnov two-sample statistical tests (Jamniczky et al., 2003;
Payne, 2003). Additionally, taxon abundance data from each assemblage were
combined, and bootstrapping analyses (1000 replicates with resampling) were
conducted using PAST © to obtain 95% confidence intervals for the estimate of
N taxa in a given assemblage.
The colour of all bones used in the taphonomic study was documented.
Other bone surface features relating to root etching, bacterial action, pH
corrosion, and calcrete encrustation were also noted. The relative degree of
weathering of the bones was determined following criteria of Behrensmeyer
(1978; Table 1), and each element was assessed for abrasion using a
descriptive scale adapted from Spencer et al. (2003; Table 2).
134
Table 1. Bone weathering stages (following Behrensmeyer, 1978).
Stage Character
0 No signs of weathering
1 Bone surface cracking
2 Deep cracking and flaking of bone surface
3 Large patches of rough, compact bone
4 Bone surface fibrous, exhibiting splintering
5 Bone falling apart in-situ, large splinters missing with deep
cracking
Mammal skeletal relative abundance was calculated using the equation:
( )EiMNINi
Ri100×= (1)
where R is the relative abundance of element i, N is the minimum number of
element i, MNI is the minimum number of individuals, and E is the expected
number of element i in a skeleton (Andrews, 1990). Determination of E was
based on comparison with modern mammal skeletons. The equation allows
comparison of numbers of different skeletal elements that occur in varying
proportions in mammalian skeletons.
Table 2. Abrasion stages of fossil bone (modified from Spencer et al., 2003).
Abrasion stage Characteristics
Absent Absent
Minimal Slight erosion to one or two points on bone
Light <25% of bone surface exhibits erosion
Moderate 25-50% of bone surface exhibits erosion
Heavy 50-75% of bone surface exhibits erosion
Extreme >75% of bone surface exhibits erosion
Cranial and dentary breakage patterns of large (>5kg) and small (<5kg)
mammals were identified in the deposit following the techniques of Andrews
(1990) and Price and Sobbe (2005; Figures 2, 3). Identification of post-cranial
breakage patterns of major limb bones (humeri, ulnae, femora, tibiae) followed
Andrews (1990). Broken limb bones were classified as proximal, shaft, or distal
135
portions. The percentage of representation for each breakage pattern was
calculated to determine potential differences between large- and small-sized
mammal skeletal breakage within and between horizons.
Figure 2. (a-g) Mammal cranial breakage categories from the QML796 assemblage (shaded
areas indicates the preserved portions).
Identification of the taphonomic agents responsible for bone fracturing can
provide significant information about the formational history of an assemblage
(Shipman et al., 1981; Villa and Mahieu, 1991). Bone fractures were classified
into one of eight main fracture patterns that commonly occur in fossil
assemblages (Figure 4; adapted from Marshall, 1989; Reed, 2003).
Figure 3. (a-l) Mammal dentary breakage categories from the QML796 assemblage (shaded
areas indicates the preserved portions).
Indices of taphonomic modification patterns of vertebrates in the deposit
mostly were derived from Andrews (1990), and their specific applications were
as described by Price and Sobbe (2005). Indices calculated include: percent of
136
post-crania to crania; percent of distal element loss; percent of fore limb loss;
percent molar tooth loss; and relative loss of molar tooth sites, as an
independent index of cranial breakage (Kos, 2003).
Figure 4. Stylised distal portion of a macropod femur indicating bone fracture patterns. (a)
Stepped. (b) Crenulated. (c) Spiral; (d) V-shaped. (e) Smooth perpendicular. (f) Irregular
perpendicular. (g) Longitudinal. (h) Impact.
Bone modification by carnivores includes a range of different tooth marks.
For example, rodents produce characteristic parallel tooth markings through
gnawing (Lyman, 1994), whereas larger carnivores generally crush bone by
static loading, which produces consistent breakage patterns (Johnston, 1989).
Sobbe (1990) identified ten categories of tooth markings on fossils from
Pleistocene deposits of the Darling Downs (Table 3), and tooth markings on
bones from QML796 were classified based on comparison to those examples.
Each identified bone also was scored with respect to the number and position of
tooth marks.
The degree of hydraulic sorting experienced by the accumulations was
determined by comparing the relative abundance of elements to experimental
results from studies by Voorhies (1969), Dodson (1973), Behrensmeyer (1975),
and Korth (1979).
137
Table 3. Characteristics of tooth markings on fossil bone that commonly occur in Darling Downs
deposits (following Sobbe, 1990).
Tooth marking Characteristics
Round bottom scratches with
anchor point
Series of closely spaced near parallel scratches;
characteristic of rodents
Blade-like impressions Long blade-like impressions to 27mm long, V-shaped in
cross section; characteristic of Thylacoleo
Crescent-shaped markings Bone surface displaced at right angles to long axis leaving
ridge of semi-attached bone at concave edge
Pits and scratches Pits round to oval to diameter of 2mm; round bottomed
scratches parallel to walls with corrugations at right angles
to long axis marks
Large deep scratches Scratches to 27mm long, 5mm wide
Fine scratches tapered at
both ends
Fine, round bottomed scratches with widest point near
middle, tapering to both ends
Round punctures Round punctures depressing compact bone surface, 3-
3.5mm in diameter; similar to Sarcophilus.
Large oval punctures Large oval punctures to 14mm long, 7mm wide
Spongy bone removal with
depressed punctures
Depressed punctures 5-8mm diameter on articular ends of
long bones
Ragged edges and hollow-
backed edges
Bone with ragged edges and associated depressions of
bone edge; attributed to carnivore gnawing
In situ bivalve taphonomy was evaluated using the coexistence index of left
and right valves (Cv) of V. ambiguus. Cv was calculated using the equation:
1
211V
VVCv
−−= (2)
where V1 is the greater number of valves and V2 is the lesser number of valves
(after Shimoyama & Hamano, 1990). Cv values range between 0 and 1 and
measure the deviation from the expected 1:1 ratio. Additionally, χ2 tests were
computed to test for preservation differences between bivalves.
Other statistical analyses were performed using SPSS © statistical software.
Correlations were considered to be significant at the 95% confidence level.
138
Figure 5. Murid age classification scheme based on M1 tooth wear. (a) Young. (b) Adult. (c)
Mature.
Faunal attributes
Vertebrate mortality profiles were determined for murids and macropods. The
age structure classification for murids was based on the degree of tooth wear of
the M1 (Figure 5). Age structure classification of larger (>5 kg) macropods was
determined using molar eruption patterns following criteria in Table 4.
Body weights of extant and extinct vertebrate taxa were derived from Hecht
(1975); Murray (1991), Strahan (1995), and Wroe et al. (2003a, b).
Table 4. Age class characteristics for macropods based on premolar and molar eruption
patterns, modified from Reed (2003).
Age class Eruption sequence
Pouch young dp2, dp3, M1 erupting
Young dp2, dp3, M1, M2 erupting
Juvenile dp2, dp3, M1-2, M3 erupting
Sub-adult dp3, M1-M3, M4 erupting (M1 & M2 worn)
Adult P3, M1-M4 (M1-3 worn)
Mature M1-M4 (all molars worn)
Senile M2-4 (molars worn)
RESULTS
Sedimentology and Stratigraphy
Stratigraphy of the deposit was determined to be more complex than was
documented in the earlier excavation, but we retain original QM stratigraphic
139
nomenclature for the main fossiliferous horizons (A7, A4 and A1) to be
consistent with pre-existing collections. The deposit is characterised by
alternating coarse- and fine-grained siliciclastic sediment, mostly arranged into
individual fining-up cycles or couplets of coarser and finer sediments with a
single coarsening-up unit near the top (denoted C1-C8; Figure 6). Fine-grained
horizons contain abundant smectite clays as evidenced by cracking behaviour in
the excavation (Figure 7). Vertebrate material occurs in each horizon, but is
most abundant in coarser units. In general, freshwater bivalves (V. ambiguus
and C. (C.) australis) and thiarid gastropods (T. (P.) balonnensis) are most
abundant in coarse horizons, but some fine-grained horizons contain scattered
shelly lenses with abundant T. (P.) balonnensis. Elongate fossil material is
generally oriented within 10° of horizontal. Fine-grained units contain rare
calcrete rhizocretions.
Figure 6. Measured section of QML796 (stratigraphic column D; see also figure 8) indicating
coarsening upward cycles and original QM nomenclature.
140
The base of the section is generally below the modern watertable and
consists of crudely bedded siltstone and claystone (Fsm), mudstone (Fm), and
interlaminated mudstone and laminated sandstone (Fl) (Table 5; lithofacies
codes of Miall, 1996). The fine-grained rocks are overlain by a very coarse to
coarse, fining-up sandstone unit (0.7-1.3 m) containing scour-fill sand (Ss) at
the base passing upwards into massive sand (Sm) (C1 on Figure 6). The basal
contact represents the highest order erosion surface in the section, and the
deposit is laterally extensive, being recorded 50 m upstream and 70 m
downstream from the excavation (Figure 8). The unit is equivalent to the ‘lower’
A7 horizon of the QM excavation. Freshwater mollusc and vertebrate fossils are
abundant along with reworked, rounded pebbles of calcrete and rarely, basalt,
at the base. The orientation of fossil bivalves (V. ambiguus) and long bones
shows a strong east-northeast to west-southwest trend (Figure 9a) and 50% of
V. ambiguus valves occur with their anterior portion directed to the eastern
quadrant (i.e., between NE and SE; Figure 9a). Both conjoined and non-
conjoined V. ambiguus are most abundant within the C1 sands, and a high
percentage of valves occur in hydrodynamically unstable positions. The top of
the C1 sandstone passes into Fm through most of the excavation, but the base
Table 5. Lithofacies classification and description (adapted from Miall, 1996).
Lithofacies code Description
Fsm Massive to crudely bedded siltstone and claystone
Fm Massive mudstone
Fl Interlaminated mudstone and laminated sandstone
Ss Scour-fill sand
Sm Massive sand
Sh Horizontal laminated sand
Sl Low-angle bedded sand
141
Figure 7. Stratigraphic exposure of site QML796. (a) Photograph of outcrop. (b) Line drawing of
stratigraphic units indicating fluvial architectural elements. See table 6 for definition of codes.
of the overlying C3 sandstone Ss rests directly on C1 sandstone to the north
(Figures 6-8). Lithofacies Ss of C2 pinches out against the base of C3 to the
north, but is otherwise separated from C1 and C2 by Fsm (Figures 6-8). The
combined C2-C3 cycles collectively represent the ‘upper’ A7 horizon of the QM
excavation. Long bones and bivalve shell orientations in C2 and C3 exhibit a
142
northwest to southeast trend (Figure 9b), and 40% of V. ambiguus valves occur
with anterior portions directed to the eastern quadrant (Figure 9a).
Figure 8. Fence diagram of consistent stratigraphic units at site QML796. (a) Plan view of
stratigraphic columns indicating position of detailed QUT-QM ‘top-down’ excavation (columns C-
E). (b) Stratigraphic columns. See table 6 for fluvial architectural element code definition.
Laterally extensive, crudely horizontally bedded Fm overlies the upper C3
sand and is overlain to the north by three stacked, fining-up, very coarse Ss and
horizontally bedded sand (Sh) units that pass upward into Fl (C4-C6; Figures 6-
8). The coarse units represent the A4 horizon of the QM excavations and do not
persist to the south, where they have been truncated against a scour surface.
The sands contain few internal structures other than fine lamination and contain
abundant mollusc and vertebrate remains, but lack the coarser pebbles and
cobbles that characterise the base of C1. Bivalves and long bones are oriented
east to west, and ~54 % of V. ambiguus valves occur with their anterior portion
directed to the eastern quadrant (Figures 9c & 10a).
143
Figure 9. Orientations of bone and large bivalves (Velesunio ambiguus) from QML796. (a) A7
‘lower’ horizon. (b) A7 ‘upper’ horizon. (c) A4 horizon. (d) FF between A1 and A4 horizons. (e)
A1 horizon.
The C6 sand passes into laterally persistent, crudely bedded to massive Fsm
and Fm. To the south this fine unit clearly lies above a scour surface that has
removed C4-C6, but no coarse lag occurs above the scour contact in the
excavation (Figures 6-8). The base of the overlying C7 unit also represents a
broad scour surface. The base of C7 consists of Ss and Fl with crude horizontal
bedding. The deposit is laterally discontinuous and thins to the west. Freshwater
molluscs are abundant, but vertebrate fossils are rare. Bivalves and long bones
from the coarse and fine C7 horizons show no obvious trend in orientation, but
~39 % of V. ambiguus valves occur with anterior portions directed to the eastern
144
quadrant (Figure 10a). The C7 sand passes into massive to crudely bedded
Fsm and Fm up section.
The highest coarse unit is the base of C8 (Figure 6). The deposit consists of
crudely laminated, coarsening-up, coarse to very coarse sand (Sl) with crude,
low-angle (<15o) accretion surfaces and a broad scoured base. The sand is
discontinuous to the north and south and thins to the west (Figure 8).
Freshwater molluscs and vertebrate fossils are abundant. Orientation of V.
ambiguus and long bones shows a strong northwest to southeast trend.
Approximately 54% of V. ambiguus valves occur with anterior portions directed
to the eastern quadrant (Figure 10a). The base of C8 is synonymous with the
A1 horizon of the QM excavations. Overlying fine-grained deposits are Fm that
has been disturbed by modern soil formation and agriculture. There is no
evidence that modern soil processes disturbed the underlying stratigraphy
documented above.
Figure 10. Characteristics of large-sized, in-situ bivalves (Velesunio ambiguus) from QML796.
(a) Orientation of anterior portion of valves. Error bars indicate binomial 95% confidence
intervals. (b) Frequency of single valves in hydraulically unstable positions and frequency of
conjoined bivalves.
145
INTERPRETATION
Four main fluvial architectural elements (sensu Miall, 1996) were identified in
the deposit (Table 6). The base of the section is interpreted as floodplain fines
(element FF) on the basis of massive to crudely horizontally bedded Fm, Fl and
Fsm.
Table 6. Fluvial architectural element classification and description (adapted from Miall, 1996).
Element Code Description Constituent lithofacies
FF Overbank fines Fm, Fl, Fsm
LA Lateral accretion Ss, Sm
CH Channel Ss, Sh
CS & CR Crevasse splay and channel Ss, Sl
The coarse parts of cycles C1-C3 (A7 horizon) represent lateral accretion
(LA) elements and consist of channel lag or channel bar deposits. The lack of
preserved channel margins in C1 precludes distinguishing between a channel
lag and a bar. However, the wide lateral extent and fining-up nature of C1 within
a floodplain fines-dominated sequence is consistent with a point bar. The
coarse sands of C3 may represent a small channel lag based on the lateral
pinching character (Figures 7, 8). The lower LA deposit (C1) represents higher
velocity currents than subsequent horizons based on the significantly coarser
grain size near the base and high order scoured base and is interpreted to have
been deposited in a main channel. The high proportion of V. ambiguus valves
preserved in hydraulically unstable positions in the lower portion of C1 may
represent deposition in deeper scour pools amongst coarse sediment. Current
direction is difficult to determine based solely on bone orientation. Long bones
orient parallel with the current in high velocity flow with the heavier ends
upstream, but may orient perpendicular to the current flow at lower velocities
(Behrensmeyer, 1990). The common fragmentation of bone with loss of heavier
146
ends in C1 complicates the issue. However, the orientations of V. ambiguus
shells provide evidence for current direction. Experimental and field results on
similarly shaped bivalves indicate that valves preferentially orient with their long
axis parallel to the flow and with their anterior ends up-current (Nagle, 1967).
Additionally, Brenchley and Newall (1970) suggested that if unidirectional
orientations of bivalves were observed in transported assemblages, then the
portion of the shell closest to the centre of gravity would be directed up-current.
For single V. ambiguus valves the centre of gravity is closest to the anterior end.
The common anterior orientation of valves in C1 to the eastern quandrant
(Figure 10a) suggests that flow was generally from east to west, which is
consistent with data from long bones and predicted flow direction based on the
modern catchment.
The succeeding LA elements (C2 and C3) were minor in comparison to C1,
and each passes upwards into lithofacies Fm, Fsm, and Fl that are interpreted
as element FF. The erosion of C3 into the top of C1 and lateral pinch-out of C2
within the excavation suggests reactivation of an abandoned channel in an
ephemeral system. C2 and C3 sands are not interpreted as levee deposits
owing to their pinching and erosive nature and separation from each other and
from C1 by FF. Combined bone and shell orientation data indicate
palaeocurrent direction for C2-C3 was from southeast to northwest. Minor
differences in flow orientation between C1 and C2-C3 (Figure 9) may reflect
channel migration over time in the ephemeral system, but all flow was basically
east to west. As the Pleistocene floodplain was geographically small, it is
unlikely that Fm deposits within the FF element represent in-channel mud
drapes, which are common in larger, sandy ephemeral channel systems where
waning flood deposition allows the settling of fines (e.g., Best et al., 2003). No
fluvial flaser-like structures were observed (e.g., Martin, 2000). The wide lateral
extent and considerable vertical variability of the FF deposits and abrupt
transitions to thin channel deposits is more consistent with a low relief
depositional surface that is susceptible to minor changes in depositional
processes (Miall, 1996). Scattered shelly lenses in the FF deposits are
147
consistent with episodic overbank deposition, and bone and shell orientation
data do not indicate significant palaeocurrent trends in the fine horizons.
The sands of C4-C6 are interpreted as stacked minor channel elements (CH)
owing to their laterally restricted occurrence, fining–up grain size, and enclosure
in FF deposits. Deposition probably occurred in minor tributaries on the
interfluve during high rainfall periods, with at least three main depositional
phases preserved. Combined bone and shell orientation data indicate that
palaeocurrent direction was from east to west. The CH deposits pass upwards
into a thick section of FF but were eroded away to the south beneath a scour
surface. Any lag deposits associated with the scour do not crop out in the
excavation, suggesting that the truncation of C4-C6 was located relatively high
on the shoulder of the eroding channel.
Coarse sands at the bases of C7 and C8 are interpreted as crevasse splay
(CS) and crevasse channel (CR) deposits, respectively (Figure 7). Element CR
was defined by the concave-up, scoured channel floor and likely proximity to a
main channel based on content of coarse reworked bone clasts. Internal scour
and fill structures between accretionary units indicate multiple episodes of
erosion and sedimentation. Bone and shell palaeocurrent direction data indicate
southeast to northwest flow. Both C7 and C8 thin to the west indicting
progradation onto the floodplain. The CR element of C8 exhibits low-angle
accretion surfaces recording growth by lateral accretion within the channel, and
the coarsening-up pattern is consistent with progressive erosion deepening the
breach during flooding.
Collectively, the point bar, flashy discharge features, scour surfaces, and
abundant abrupt lithofacies shifts between Sh, Sl, Fm, and Fl suggest that site
QML796 represents ephemeral channel deposits and overbank fines in a
meandering stream system (Miall, 1996). That interpretation is supported by the
ecology of the abundant V. ambiguus. Extant populations are generally
associated with low velocity creeks and billabongs, rarely occurring in large,
high-velocity rivers (Sheldon & Walker, 1989). Larger-sized unionoids with
elongate, ‘winged’ shells, such as Alathyria spp., are more commonly
148
associated with permanent high-velocity rivers, but were not identified in the
Kings Creek deposits.
Stratigraphic correlation within Kings Creek catchment
The C1 LA deposit of QML796 can be lithologically and biostratigraphically
correlated to the basal channel deposit of QML1396 (Horizon B of Price &
Sobbe, 2005) (Figure 11). Site QML1396 represents a basal channel deposit
passing upwards into overbank deposits (Price & Sobbe, 2005). The basal
channel deposit is laterally extensive, fines upwards and has abundant
freshwater molluscs and vertebrate fossils. It occurs at approximately the same
elevation with respect to the modern watertable as C1 at QML796. Thicker (~9
m) overlying FF deposits at site QML1396 contain alternating Sl and Fm with
desiccation cracks, mottled calcrete and Fe nodules.
Figure 11. Stratigraphic relationships between QML796 (stratigraphic column D) and QML1396.
Site QML783 (= ‘Ned’s Gully’ in Molnar, et al., 1999; Roberts et al., 2001), in
the southern bank of Ned’s Gully, Kings Creek catchment, was interpreted as
an overbank abandoned flood channel deposit (Figure 1; Molnar et al., 1999).
Articulated and associated specimens are abundant. Molnar et al. (1999)
149
suggested that there was no bias in species size represented in the deposit as
both large- and small-sized mammals were recorded. The low degree of
scattering of skeletal material may indicate rapid burial by slumping of an
unstable gully wall (Molnar et al., 1999). Tufa was subsequently found at the site
suggesting a possible spring deposit, but was not collected in situ. Regardless,
the absence of freshwater molluscs indicates that the deposit was not a main
watercourse during the period of deposition (Molnar et al., 1999). Stratigraphic
relationship of QML783 to sites QML796 and QML1396 remains unclear.
Bivalve Taphonomy
Cv values indicate that a disproportionately high number of single left valves of
V. ambiguus were preserved in the deposit (A7: Cv = 0.62, N = 379; A4: Cv =
0.52, N = 229; A1: Cv = 0.66, N = 103). Single left valves contributed 60-65% of
all non-conjoined V. ambiguus valves within each main fossiliferous horizon (A7:
χ2 = 19.97, df = 1, σ = <0.001; A4: χ2 = 22.01, df = 1, σ = <0.001; A1: χ2 =
4.28, df = 1, σ = 0.039). Non-conjoined valves generally occurred in
hydraulically stable positions (i.e. concave down; Brenchley & Newall, 1970), but
single valves dipping between 20o and vertical to concave up (i.e., unstable)
positions were most common in A7 (Figure 10b). Conjoined bivalves were twice
as abundant in A1 as in other horizons (Figure 10b).
INTERPRETATION
Bivalves generally disarticulate after death with initial ratios of preserved left and
right valves generally near 1:1 (i.e., Cv = 1) at the source spot (Shimoyama &
Fujisaka, 1992) where the probability of preserving complete and undamaged
conjoined shells is highest (Cadée, 1968). The low Cv of V. ambiguus at
QML796 indicates transport from the original source spot, which is consistent
with a flashy, ephemeral discharge regime. The left-right sorting phenomenon of
bivalves and brachiopods during transport has been documented in marine
environments (Martin-Kaye, 1951; Boucot et al., 1958; Johnson, 1960; Behrens
& Watson, 1969) but not in non-marine environments. Low Cv values in marine
150
environments generally reflect minor differences in the hydrodynamic properties
of left and right valves, even where valves are bilaterally symmetrical. However,
bivalves in marine environments are generally exposed to a greater variety of
currents and swashing effects than are bivalves in uni-directional currents in
most low-velocity water courses. Random walk simulations of shell diffusion can
produce low Cv’s in marine environments with statistically small samples
(Shimoyama & Fujisaka, 1992). However, Cv approaches unity with larger
sample sizes. Regardless, Cv values decrease with increasing distance from
the source spot. Hence, the QML796 bivalves probably experienced significant
transport from their source spots. The Cv values are closer to unity for the A1
horizon, which also has the highest proportion of conjoined bivalves (Figure
10b), and are lowest for A4, which has the lowest proportion of conjoined
bivalves (Figure 10b). Thus, the source spot for A1 bivalves may have been
closer to the final point of deposition than for A7 and A4, which is consistent
with A1 representing a splay deposit and A4 and A7 representing channels.
Vertebrate Taphonomy
Fossil material is unequally distributed through the deposit. Fossils recovered
from FF deposits are poorly preserved and markedly less abundant than fossils
in coarser-grained horizons. Due to the paucity of fossil material in the fine-
grained horizons, taphonomic inferences are based on fossil material recovered
from the coarser-grained horizons (A7, A4 and A1). Few meaningful data could
be obtained from the tens of thousands of small (generally <20 mm),
unidentifiable bone fragments that represent differing stages of preservation,
weathering and abrasion, and that range from angular bone shards to rounded
bone pebbles. Thus, the taphonomy discussed below was based on identifiable
species and/or skeletal elements.
BONE APPEARANCE
Fossil bone colours range from creamy-white, brown, brown-red, to black,
representing variable degrees of mineralisation. Brown-red bones were more
151
common in A4 and A7 than in A1, but no definitive trend in colour was identified.
Root etching of bone surfaces was uncommon (<1%) in each horizon, and
where present, generally affected less than 5% of the bone surface. There was
no observed evidence of pH-related or bacterial etching (e.g., Chaplin, 1971) on
any fossil material from the deposit. Calcrete encrustations on bone are
relatively uncommon but are slightly more abundant in the A1 horizon.
The majority of identifiable specimens from the deposit represent weathering
stages 0-2, showing either no weathering or some cracking and exfoliation of
the outermost bone surface (Figure 12) (criteria of Behrensmeyer, 1978). For
large-sized mammals, A1 exhibits the highest proportion of unweathered bone
(Figure 12a). Horizon A7 exhibits the highest degree of weathered bone and the
only material in weathering stage 3 (Figure 12a). Small-sized mammal material
is generally within weathering stage 0 (Figure 12b).
Figure 12. Weathering of bone from QML796. (a) Large-sized mammals. (b) Small-sized
mammals. See table 1 for definition of weathering stages. Error bars indicate binomial 95%
confidence intervals.
152
FAUNAL ATTRIBUTES
Species recovered from the deposit are listed in tables 7 and 8. In terms of
abundance and diversity, mammals dominated the terrestrial faunal component
in each horizon (Tables 7 and 8). At the family level, murids were the most
common group in each horizon. Several groups are rare in the assemblage,
including birds, monotremes, vombatids (wombats), and palorchestids
(marsupial tapirs). Other groups were recovered from only one horizon (e.g.,
potoroids in A4) or were represented by single specimens (e.g., thylacinids in
A4).
Table 7. MNI (minimum number of individuals) of non-mammalian taxa for main fossiliferous
horizons at QML796 (excluding bivalves and Thiara (Plotiopsis) balonnensis). * indicates species
recorded solely by abraded material.
Class Family Species A7 A4 A1
Gastropoda Planorbidae Glyptophysa gibbosa - 1 -
Gyraulus gilberti 131 133 58
Punctidae Paralaoma caputspinulae 1 1 -
Charopidae Coencharopa sp. 2 6 2
Gyrocochlea sp. 5 29 9
Rhytididae Strangesta sp. - - 1
Succineidae Austrosuccinea sp. - 1 1
Osteichthyes (Teleostei)
? Teleost gen. et. sp. indet. 94 152 96
Anura Myobatrachidae Limnodynastes tasmaniensis 1 4 4
L. sp. cf. L. spenceri - 1 -
Kyarranus sp. 1 - -
Reptilia Chelidae Chelid gen. et sp. indet. 4 20 4
Agamidae Tympanocryptis lineata 19 31 16
Physignathus leseurii 44 1 3
153
Table 7 continued
Scincidae ‘Sphenomorphus Group’ sp. 1 2 4 5
‘Sphenomorphus Group’ sp. 2 2 6 6
‘Sphenomorphus Group’ sp. 3 - 3 -
Tiliqua rugosa 4 20 7
Varanidae Varanus sp. 3 1 3
Megalania prisca 52 51 58
Elapidae Elapid gen. et sp. indet. 6 37 17
Crocodylidae Crocodylid gen. et. sp. indet. 2 4* 1*
Aves ? Aves gen. et sp. indet. - - 6
Anatidae Anatid gen et. sp. indet. sp. 1 - 1 -
Anatid gen et. sp. indet. sp. 2 - 1 -
Rallidae Gallinula mortierii - - 1
Casuriidae Dromaius novahollandiae 1 1 1
TOTAL 374 509 299
Analytical rarefaction data tend towards an asymptote for each of the
assemblages at site QML796 (Figure 13a). Although the A4 horizon
assemblage contained the most samples, the observed biotic diversity
decreased from A7 (44 taxa) to A4 (39 taxa) and from A4 to A1 (33 taxa) based
on a subsample number of 705 individuals following rarefaction (Figure 13a).
Kolmogorov-Smirnov independent two sample tests comparing the rarified
curves indicated that the A7 and A4 assemblages were not significantly different
(z = 1.06; σ = 0.206). However, the A1 assemblage was significantly less
diverse than both A7 (z = 4.36, σ = <0.001) and A4 (z = 3.40, σ = <0.001).
Hence, sampling cannot account for the observed patterns of diversity. A
bootstrap analysis was applied to test whether the sampled assemblages were
derived from the same initial community, thus testing the null hypothesis that the
observed decrease in diversity (i.e., possible local extinctions) was caused by a
154
synchronous event that occurred some time after deposition of the A1 horizon.
Bootstrap analyses indicated that the observed diversity of A7 and A4 fit within
the 95% confidence boundaries predicted based on the original sample sizes
(Figure 13b). However, the observed diversity of A1 fell below the lower
predicted 95% confidence boundary (Figure 13b), suggesting that the
assemblage was derived from a different, less diverse biotic community than
were A7 and A4.
Figure 13. Diversity measures for QML796. (a) Rarefaction curves for assemblages. (b)
Bootstrap results for assemblages indicating predicted diversity (95% confidence intervals) and
observed results.
Diversity was also compared between the lithologically equivalent units at
QML796 (A7 horizon) and QML1396 (Horizon B). The abundance data of
equivalent taxa was rarified, and Kolmogorov-Smirnov tests based on
standardised subsample sizes (16 individuals) indicated that the diversity was
not significantly different (z = 1.06, σ = 0.211). Additionally, with the exception of
a single Thylacinus cynocephalus specimen, a carnivorous species that is
generally rare in Darling Downs fossil deposits, there are no taxa represented in
155
the basal channel unit of QML1396 that are not also represented in the LA
deposit of QML796. The overall more diverse faunal assemblage of QML796
probably reflects more intensive sampling at QML796 than at QML1396.
Table 8. MNI (minimum number of individuals) of mammalian taxa for main fossiliferous horizons
at QML796. * indicates species recorded solely by abraded material.
Class Family Species A7 A4 A1
Mammalia Ornithorhyncidae Ornithorhyncus anatinus - 1 -
Tachglossidae Tachyglossus sp. - 1 -
Zaglossus sp. 4 - -
Dasyuridae Dasyurid gen. et. sp. indet. 1 1 4
Sminthopsis sp. 2 2 1
Dasyurus sp. cf. D. viverrinus 5 13 7
D. vivverinus 1 4 4
Antechinus sp. - 1 -
Sarcophilus laniarius 2 - 5
Thylacinidae Thylacinus cynocephalus - 1* -
Peramelidae Peramelid gen. et. sp. indet. 7 15 11
Perameles sp. 1 6 1
P. bougainville 2 - -
P. nasuta 2 1 3
P. sobbei 6 5 6
Isoodon sp. - 4 -
I. obesulus 2 2 -
Vombatidae Vombatid indet. 3 2 1
Vombatus sp. - - 1
Phascolonous gigas 1 - -
Palorchestidae Palorchestes azael 1 - -
Palorchestes sp. 1 - -
156
Table 8 continued
Diprotodontidae Diprotodon sp. 26 42 2*
Zygomaturus trilobus 4 - -
Thylacoleonidae Thylacoleo carnifex 1 1 -
Potoroidae Bettongia sp. - 1 -
Aepyprymnus sp. - 3 -
Macropodidae Macropod gen. et. sp. indet. 26 112 33
Sthenurine gen. et. sp. indet. - 2 -
Sthenurus andersoni - 1* -
Troposodon minor 14 10 3*
Macropus sp. 22 3 1
Macropus sp. A - 1 -
M. agilis siva 18 18 -
M. titan 7 11 4
M. pearsoni - - 1*
Protemnodon sp. 14 18 2
Pr. brehus 1 8 1
Pr. roechus 3 7 -
Pr. anak 19 12 3
Muridae Murid gen. et. sp. indet. 387 905 478
Ps. gracilicaudatus 4 - -
Ps. australis 18 20 4
Pseudomys sp. A - 1 -
Rattus sp. (close to R. tunneyi
or R. sordidus)
8 6 7
Hydromys chrysogaster 2 2 1
TOTAL 615 1243 584
157
The percentage of non-aquatic taxa representing different body weights at
QML796 indicates that small-sized taxa dominated each assemblage and were
slightly more common in A1 (Figure 14). Additionally, the A1 horizon had only a
single taxon >100 kg, Megalania prisca. Taxa >100 kg were slightly more
abundant in A7 than in other horizons.
Figure 14. Body sizes of terrestrial vertebrate taxa from QML796. Error bars indicate binomial
95% confidence intervals.
Large-sized macropods were poorly represented in A1. Hence, mortality
profiles are based only on larger-sized macropods from A4 and A7 (Figure 15a).
Macropod age profiles for A4 and A7 are generally negatively skewed towards
younger individuals. Sub-adult individuals are most common in A7, whereas
mature adults are most common in A4. Mortality profiles show that murid
mortality was evenly distributed for the three age classes in A4 and A7 (Figure
15b). However, murid mortality was highest for young individuals and lowest for
aged individuals in A1.
SKELETAL PART REPRESENTATION
With the exception of molluscs, non-mammalian skeletal elements are poorly
represented at QML796 (Table 9). Where present, they are generally
represented by fragmentary material. Comparison of non-mammalian vertebrate
post-cranial elements (Table 9) to the MNI data (Table 7) indicates a high
relative loss of post-cranial skeletal material.
158
Tab
le 9
. MN
E (m
inim
um n
umbe
r of e
lem
ents
) of n
on-m
amm
alia
n ve
rtebr
ates
with
in e
ach
horiz
on (e
xclu
ding
an
artic
ulat
ed in
divi
dual
aga
mid
,
Phy
sign
athu
s le
seur
ii, c
olle
cted
from
the
A7
horiz
on).
T
eleo
sts
Anu
rans
C
helid
s C
roco
dylid
s A
gam
ids
Sci
ncid
s V
aran
ids
Ela
pids
A
ves
A
1 A
4 A
7 A
1 A
4 A
7 A
1 A
4 A
7 A
1 A
4 A
7 A
1 A
4 A
7 A
1 A
4 A
7 A
1 A
4 A
7 A
1 A
4 A
7 A
1 A
4 A
7
Max
illae
-
- -
- -
- -
- -
- -
- 9
17
10
1 2
- -
- -
- -
- -
- -
Den
tarie
s -
- -
- -
- -
- -
- -
- 10
14
10
10
12
4
- -
- -
- -
- -
-
Teet
h -
- -
- -
- -
- -
- 2
2 -
- -
- -
- 13
9
13
- -
- -
- -
Ver
tebr
ae
91
110
41
- -
- -
- -
- -
- 2
23
10
18
41
21
- -
- 10
34
6
- -
-
Pel
ves
- -
- 4
5 2
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
-
Lim
b bo
nes
- -
- -
- -
- -
- -
- -
- 1
- -
- -
- -
- -
- -
1 4
-
Spi
ne/ r
ib
3 42
48
-
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
-
Ope
rcul
um
2 5
5 -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
-
Ost
eode
rm/
shel
l
- -
- -
- -
4 20
4
- 2
- -
- -
7 15
4
48
43
42
- -
- -
- -
Egg
she
ll -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- -
- 1
1 1
159
Figure 15. Mortality profiles of mammals from QML796. (a) Macropods, excluding A1 individuals.
(b) Murids. See table 4 and figure 5 for definitions of age classes. Error bars indicate binomial
95% confidence intervals.
Cranial elements are the best represented elements of both large and small
mammals in each horizon (Figure 16). However, all skeletal elements are under-
represented in comparison to numbers of elements expected in complete
skeletons. For large-sized mammals, A4 has the highest relative abundance of
all skeletal elements. A1 is particularly devoid of large mammal material, with
maxillae and molars the only skeletal elements with greater than 6% relative
abundance. For small mammals, incisors are abundant in each horizon (>80%).
Small mammal post-cranial material is poorly represented in each horizon with
no element represented by greater than 10% relative abundance.
SKELETAL BREAKAGE
Large-sized mammal cranial material of A4 is more fragmentary than that of A7
and A1 (Figures 17-18). The only complete cranium (Diprotodon sp.) was
collected from the A7 horizon. No complete dentaries were recovered from any
horizon, and maxillae and dentaries of large mammals are rare in A1. Thus,
160
comparisons of large mammal maxillae and dentary breakage patterns were
restricted to A4 and A7 (Figures 17-18). Large mammal dentaries from A4 are
Figure 16. Skeletal relative abundance of mammals from QML796. (a) Large-sized mammals;
(b) Small-sized mammals.
more fragmentary and exhibit a wider range of breakage patterns than A7 large
mammals. For small mammals, dentaries lacking the inferior border of the
horizontal ramus were the most abundant breakage pattern identified in each
horizon. Small mammal maxillae were more completely preserved in A7.
Of the major limb bones, the number of complete elements is very low for
both large and small mammals (Table 10). Moderate proportions of complete
specimens occur for all post-cranial elements (Figure 19), but robust elements
(calcania, phalanges and unguals) represent 48-98 % of those complete
161
Figure 17. Frequencies of cranial breakage patterns of mammals from QML796. (a) Large-sized
mammals. (b) Small-sized mammals. See figure 2 for illustrations of breakage patterns. Error
bars indicate binomial 95% confidence intervals.
specimens. Due to relatively low abundance of post-cranial remains, breakage
trends between horizons could not be confidently assessed (Table 10).
Proportions of fracture patterns of post-cranial material show that fracture
patterns of dry or fossilised bone, particularly transverse fractures (fracture
pattern F), make up the majority of specimens in each horizon for both large
and small mammals (Figure 19). Green type fractures, although rare, are slightly
more common in A4 and A7 than in A1 (Figure 19).
Skeletal modification indices suggest that there was a significant loss of post-
cranial skeletal material for both large and small mammals within each horizon
(Table 11). Proximal limb elements (femora and humeri) are more abundant
than distal elements (tibiae and radii) for large and small mammals in horizons
A1 and A4. The ratio of distal to proximal elements is approximately 1:1 for
large and small mammals in A7. Forelimb elements (humeri and radii) are less
represented than hindlimbs (femora and tibiae) for large- and small-sized
mammals of A1 and large-sized mammals of A4 and A7. Hindlimbs are slightly
162
better represented than forelimbs for small-sized mammals in A4 and A7. Large
numbers of isolated molars occur in each horizon, associated with molar tooth
site losses (Table 11).
Table 10. Breakage of major post-cranial limb elements from QML796.
Limb bone <5kg mammals >5 kg mammals
A1 A4 A7 A1 A4 A7
N (%) N (%) N (%) N (%) N (%) N (%)
Humerus
complete 0 (0.0) 4 (44) 3 (16) 0 (0) 7 (17) 0 (0)
proximal 15 (50) 0 (0) 1 (5) 0 (0) 6 (15) 2 (20)
shaft 10 (33) 4 (44) 9 (47) 1 (50) 8 (19) 1 (10)
distal 5 (17) 1 (12) 6 (32) 1 (50) 20 (49) 7 (70)
Femur
complete 3 (17) 4 (17) 1 (10) 1 (33) 4 (11) 0 (0)
proximal 12 (67) 2 (9) 4 (40) 1 (33) 18 (49) 7 (78)
shaft 2 (11) 16 (70) 2 (20) 1 (33) 3 (8) 0 (0)
distal 1 (5) 1 (4) 3 (30) 0 (0) 12 (32) 2 (22)
Ulna
complete 0 (0) 0 (0) 0 (0) 0 (0) 1 (7) 0 (0)
proximal 2 (29) 5 (63) 2 (50) 0 (0) 10 (67) 5 (84)
shaft 1 (14) 1 (12) 2 (50) 0 (0) 2 (13) 1 (16)
distal 4 (57) 2 (25) 0 (0) 0 (0) 2 (13) 0 (0)
Tibia
complete 1 (4) 0 (0) 0 (0) 1 (50) 0 (0) 0 (0)
proximal 6 (26) 3 (14) 2 (7) 0 (0) 3 (27) 2 (14)
shaft 1 (4) 17 (81) 12 (86) 1 (50) 5(46) 2 (14)
distal 15 (66) 1 (5) 1 (7) 0 (0) 3 (27) 10 (72)
163
Table 11. Skeletal modification indices for small- and large-sized mammals from QML796.
Skeletal modifications < 5kg mammals > 5kg mammals
A1 A4 A7 A1 A4 A7
Post-cranial element loss 29.63 21.02 28.22 20.00 67.50 42.11
Distal element loss 63.3 18.4 92.9 66.7 75.0 105.9
Fore limb loss 58.1 114.8 105.9 25.0 32.4 66.7
Molar tooth loss 786.7 660.0 603.4 725.0 271.4 116.1
Molar tooth site loss 186.7 155.8 355.2 100.0 694.7 567.7
Figure 18. Frequencies of dentary breakage patterns of mammals from QML796. (a) Large-sized
mammals. (b) Small-sized mammals. See figure 3 for illustrations of breakage patterns. Error
bars indicate binomial 95% confidence intervals.
CARNIVORE MODIFICATION
Carnivore or scavenger markings on bone are rare (<3%) for horizons A7 and
A1. V-shaped grooves with associated depressed fractures (sensu Sobbe,
164
1990) are the only type of tooth markings observed on A7 fossil bone. Fine
scratches and crescent-shaped markings (sensu Sobbe, 1990) are the only type
of tooth markings observed on A1 fossil bone. Carnivore markings are more
abundant and diverse on A4 fossil bones (N = 32, ~8%; Figure 20a). V-shaped
blade markings are the most common carnivore markings (Figure 20b) and are
commonly associated with depressed punctures. Limb bones are the most
abundant skeletal element containing tooth markings (Figure 20c), with those
tooth markings generally confined to the shaft (Figure 20d).
Figure 19. Fracture patterns of mammal skeletal elements from QML796. (a) Large-sized
mammals. (b) Small-sized mammals. See figure 4 for definition of fracture patterns. Error bars
indicate binomial 95% confidence intervals.
ABRASION AND HYDRAULIC SORTING
Abrasion was absent in 45-61 % of identifiable large-sized mammal specimens
(Figure 21a). A1 exhibits the lowest proportion of unabraded large mammal
specimens, and the highest proportions of heavily and extremely abraded
skeletal material. Small-sized mammal material is largely unabraded in all
horizons (Figure 21b).
165
Figure 20. Carnivore tooth markings of bone from the A4 horizon at QML796. (a) Frequency and
degree of tooth marked bone. (b) Frequency of types of markings observed. (c) Frequency of
skeletal elements with tooth markings. (d) Frequency of the positions of tooth markings on limb
elements. See table 3 for definition of tooth mark categories. Error bars indicate binomial 95%
confidence intervals.
Comparison of relative abundance data of skeletal elements for mammal
species to experimental data (Voorhies, 1969; Behrensmeyer, 1975; Dodson,
166
1973, Korth, 1979) (Figure 22) suggests that skulls and maxillae of large
mammals are poorly represented in the deposit. However, the majority of
elements recorded represent those elements that are transported in the middle
to middle-late categories of fluvial transport. For small mammals, skeletal
elements are dominated by those that are transported in the middle-late
category of dispersal. Elements that are among the first to be transported by
flowing water are uncommon for both large and small-sized mammals.
Figure 21. Degree of abrasion of mammal skeletal material from QML796. (a) Large-sized
mammals. (b) Small-sized mammals. See table 2 for definition of abrasion stages. Error bars
indicate binomial 95% confidence intervals.
ARTICULATED AND ASSOCIATED MATERIAL
Only three examples of articulated and associated material were observed in
the deposit. An associated Protemnodon sp. calcaneum and cuboid were
collected from the thin coarse layer (2280-2330 mm) just below the A1 horizon
(Figure 23a). They were separated by approximately 15 mm and matched each
other well.
167
Figure 22. Percent relative abundance of skeletal elements from QML796 aligned with
comparative results of skeletal element transportability in hydraulic systems. (a) Large-sized
mammals, following Voorhies (1969) and Behrensmeyer (1975). (b) Small-sized mammals,
following Dodson (1973) and Korth (1979) (I, early transported elements; I/II, early-middle; II,
middle; II/III, early-late; III, late).
An associated Macropus titan left pelvis, femur, tibia and calcaneum were
recovered from A4 (1780-1880 mm; Figure 23b). The specimens were
associated on the basis of size, proximity to each other, and age of the
individual; the femur and tibia were missing their proximal and distal epiphyses
indicating that the individual was a sub-adult. An additional Macropus sp. cf. M.
titan humerus missing the proximal and distal ends was collected from the same
depth. The specimen compares well for size with the associated elements, but
could not be associated with confidence.
Several skeletal elements of a single water dragon (Physignathus leseurii)
individual were recovered during sieving of bulk sediments from the A7 horizon.
The individual is represented by 18 cranial and dentary elements, 18 vertebrae,
and 8 other post-cranial elements. Considering the high proportion of the
skeleton collected, and tendency for squamate cranial and post-cranial
168
elements to disarticulate readily after death, the specimen may have been
articulated.
Figure 23. Associated skeletal material from QML796. (a) Protemnodon sp. calcaneum and
cuboid from the small coarse layer below the A1 horizon (2280-2330mm). (b) Macropus titan left
pelvis, femur, tibia and calcaneum from the A4 horizon (1780-1880mm). Shaded bones indicate
associated material.
Taphonomic interpretation
The abundance of unidentifiable, small, broken bone fragments is consistent
with a fluvial setting, and highly abraded, rounded bone pebbles suggest
multiple episodes of reworking and transport within the confines of the small
169
catchment. Taphonomic interpretations are based on identifiable fossil bone so
as to yield more palaeobiological and palaeoecological information, but it is
recognised that some components of the assemblage may have had different
taphonomic pathways leading to their final deposition, including reworking from
older deposits. The focus on better preserved material allows independent
conclusions regarding the probability of reworking to be drawn for specific
specimens. The critical task is to differentiate between ecologic and taphonomic
bias as the causes of observed trends in diversity and abundance.
Low pH-etching of fossil material is considered not to have biased
preservation at QML796 owing to: 1) the occurrence of calcrete, both in situ in
FF and as reworked clasts, throughout the deposit; 2) abundant well preserved
mollusc shells; and 3) the general lack of acid-etched bone. Patterns of bone
abundance probably reflect other taphonomic processes. The greater degree of
calcrete encrustation on fossil material from the A1 horizon may reflect its
relatively high position above the watertable and seasonally dry climate. Minimal
root etching of fossil material suggests that stable vegetation with deep root
systems may not have been permanently established over the deposit in most
recent times due to the on-going erosion and semi-regular filling of the
abandoned channels. Price and Sobbe (2005) concluded that the catchment
hosted increasing levels of shallow-rooting grasses at the expense of deeper
rooting shrubs and trees subsequent to deposition of the basal sequence at
nearby QML1396.
BIAS RELATING TO FAUNAL GROUPS
In modern Australian faunal communities, marsupials, birds, frogs, turtles, and
snakes are most diverse in the continental margin regions where rainfall is
greatest, whereas lizards tend to be more diverse in arid inland areas (Pianka &
Schall, 1981). However, in all bioregions, birds and lizards dominate vertebrate
communities in terms of diversity, being 10-30 times and 2-10 times more
diverse than marsupials, respectively (Pianka & Schall, 1981). However, the
diversity of vertebrate groups at QML796 differs markedly, with marsupials
170
dominating. Such a result probably reflects a variety of taphonomic and ecologic
factors. Generally, the most common identifiable elements of non-mammalian
vertebrate taxa in QML796 are maxillae, dentaries, vertebrae, and osteoderms
(Table 9). All other cranial and post-cranial elements are poorly represented.
For reasons discussed above, preferential dissolution of small-sized bones in
acidic soils is unlikely to have caused the bias. Unfortunately, few studies have
addressed the causes of such bias, instead focussing on mammalian
accumulation in fossil deposits. It has been assumed that the remains of non-
mammals accumulate via similar taphonomic pathways to mammals (Martin,
1999), and that may be true for larger groups such as dinosaurs (Dodson,
1971). However, that may not be the case for smaller non-mammalian terrestrial
vertebrates (Behrensmeyer, 1975). Differences in preservability and
transportability of non-mammalian groups such as squamates and birds may be
attributed to hydrodynamic and/or density related factors (Vickers-Rich, 1991;
Behrensmeyer et al., 2003), but additional research is required in order to better
understand the exact taphonomic processes involved.
Several groups of mammals are uncommon in the deposit, possibly reflecting
their rarity in the living community. For example, monotremes, vombatids,
palorchestids and potoroids are uncommon at QML796 and constitute only
minor components of most other Australian Pleistocene vertebrate assemblages
(Molnar & Kurz, 1997; Murray, 1991; 1998; Reed & Bourne, 2000) presumably
owing to palaeobiological factors such as having had small standing
populations, solitary habits, and/or occupation of proximal versus distal habitats.
The rarity of Sarcophilus sp., Thylacinus cynocephalus and Thylacoleo carnifex
at QML796 is expected as they were carnivores (Molnar & Kurz, 1997). Other
groups that are absent in the Darling Downs fossil record (e.g., possums,
koalas) are rare in other Australian fossil deposits, reflecting their arboreal
habits (Murray, 1991).
Certain species recorded in the assemblage are represented solely by
abraded material. Abrasion on all bone surfaces is consistent with fluvial
transport (Shipman, 1981), but there is a paucity of experimental data to aid
171
determination of the duration or velocity of transport. Hence, it is only possible
to conclude that non-abraded bone is unlikely to have been subjected to
substantial transport over considerable distances. Within QML796, the single
Macropus pearsoni specimen (isolated molar) from A1 is moderately abraded,
suggesting that it was significantly transported prior to deposition. Additionally,
Diprotodon sp. and Troposodon minor are represented only by severely abraded
material within A1. Thylacinus cynocephalus and Sthenurus andersoni are
represented solely by abraded material within A7 and/or A4. As long-distance
transport can be ruled out in the catchment, such specimens may have been
reworked from older deposits, thus being abraded in lags on different occasions.
Hence, they may not be coeval with other taxa in their respective horizons.
Body size distributions of species indicate that larger-sized taxa are slightly
proportionally more abundant in A7, and small-sized taxa are proportionally
more abundant in A1. Hypotheses to explain those differences in body size
representation include: 1) larger-sized species were missed during sampling in
the upper units; 2) bias against accumulation of large-sized taxa occurred during
deposition of the A1 horizon; and 3) geographic range changes (i.e., local
megafauna ‘extinctions’) of large-sized taxa occurred between the time of
deposition of A7 and A1.
Hypothesis 1 is rejected because each horizon experienced the same
intensive sampling; it is unlikely that larger-sized taxa were missed preferentially
in the upper units. Additionally, rarefaction analysis suggests that observed
diversity does not reflect sampling bias. The absence in horizon A1 of taxa such
as Thylacoleo carnifex, which has a MNI of 1 in both horizon A7 and A4, could
result from its initial rarity (e.g., Signor & Lipps, 1982), but the large species
Diprotodon sp. has a MNI of 26 in A7, and 42 in A4. The occurrence of only two
abraded Diprotodon specimens in horizon A1 is unlikely to reflect sampling bias,
but may represent reworking of older bones into that horizon. Regardless, many
large-sized taxa appear to be absent from horizon A1 for reasons other than
sampling bias.
172
Hypothesis 2 relies on sedimentological and taphonomic data for testing.
Bones act as sedimentary particles in fluvial systems and are sorted according
to their settling velocities and hydrodynamic characteristics (Behrensmeyer,
1975). Settling velocities are related to bone size and density. For example, a
Protemnodon molar with a 3.1 cm3 volume has a hydraulic equivalence of a 10
mm quartz spheroid, and a Protemnodon metatarsal (93 cm3 volume) and
Diprotodon molar (70 cm3 volume) both have hydraulic equivalences of large
gravel (Behrensmeyer, 1975). Coarse-grained horizons, such as A7, would be
expected to contain larger-sized bones (and taxa) than finer-grained horizons on
the basis of fluvial sorting alone. However, apart from basal lags, overall mean
grain sizes for each of the fossiliferous horizons are not significantly different
(Figure 6), and all assemblages are dominated by small-sized individuals. As
current velocities capable of sorting and concentrating large bones would have
removed most of the smaller bones, the occurrence of both together attests to
the variability of flow regime and episodic nature of deposition. Regardless, the
A4 horizon sampled adult individuals of very large-size taxa such as Diprotodon,
so it would be expected to have had the potential to sample other very large-
sized taxa such as Zygomaturus (~500 kg), Palorchestes (~300 kg) or
Phascolonous (~150 kg). However, unabraded skeletal remains of those taxa
are absent from both A4 and A1. Similarly, unabraded material from adult
individuals of large-sized taxa occur in the A1 horizon, but they are limited to
Megalania prisca (~650 kg), Macropus titan (~85 kg), Protemnodon anak (~50
kg), and Pr. brehus (~75 kg). Thus, A1 also had the potential to sample large-
size taxa, such as Palorchestes, Troposodon minor (~45 kg), M. siva (~25 kg)
and Pr. roechus (~85 kg), but those taxa were recovered only from A7 and A4.
In the case of M. siva in particular, horizons A4 and A7 both had MNI of 18, but
no specimens were identified in A1. Its absence is unlikely to be due to
hydraulic sorting. Hence, each main fossiliferous horizon appears to have had
roughly equal potential to sample similarly large-sized taxa, and hypothesis 2 is
not supported.
173
Observed differences in body size distributions with loss of large-sized taxa
up section is more consistent with hypothesis 3, geographic range adjustments
or progressive local extinctions of species during the period of deposition. A
similar loss of large-sized taxa occurred from lower to upper coarse-grained
horizons at nearby QML1396, but in that case taphonomic data did not allow
exclusion of hydraulic sorting as the cause of the pattern (Price & Sobbe, 2005).
At QML796, hydraulic sorting would, if anything, limit the amount of reworked
large-sized material entering the crevasse channels and splays of horizon A1,
as the largest material in the bed load of the main channel might not be
transported high enough in the water column to reach the breach. Where such
reworked material did become entrained in a crevasse channel, it would be
deposited proximally, and that may explain the occurrence of the heavily
abraded Diprotodon material in A1.
MORTALITY PROFILES
The mortality curve for murids approaches that of a typical natural attrition
curve, where juveniles are the highest represented age class and seniles are
the least represented. However, for macropods within the A7 and A4 horizons, a
greater number of sub-adult to adult individuals were selected. Such age
frequency distributions suggest that some bias selected individuals in their
prime years of reproduction, possibly after breeding seasons where the stresses
relating to reproduction lead to malnutrition (Lyman, 1994). Similar observations
have been made for extant populations of some marsupial taxa such as
Antechinus (Strahan, 1995). However, such mortality patterns have not been
reported for extant macropods. Mortality profiles dominated by mature
individuals were reported for Mesembriportax acrae and Ceratotherium praecox
populations from Pliocene deposits of South Africa (Klein, 1982), and Macropus
sp. cf. M. rufogriseus populations from Pleistocene deposits of Australia
(Pledge, 1990). Klein (1982) suggested that the lack of juvenile M. acrae and C.
praecox individuals may reflect removal before burial due to carnivore or
scavenger feeding, but carnivore modification data for site QML796 discussed
174
below are equivocal. Pledge (1990) explained the absence of younger M. sp. cf.
M. rufogriseus individuals by the fragility of their bones so that measurable
maxillae and dentaries were not preserved. However, the QML796
assemblages are dominated by very small-sized individuals (Figure 14) whose
skeletal elements were probably more vulnerable to destruction than
macropods, thus, differential preservability of large macropods of varying sizes
is not supported for QML796. The macropod mortality profiles of QML796 also
resemble those of Pleistocene diprotodontoids and macropods from Bacchus
Marsh, Lancefield Swamp, Reddestone Creek, and Spring Creek, eastern
Australia (Horton, 1984; Long & Mackness, 1994). Those mortality profiles were
explained by the loss of resources caused by a series of droughts (Horton,
1984). Populations were exposed to a combination of over-grazing and
waterhole tethering effects, initially removing vulnerable age classes (young and
senile), resulting in a population of mature individuals (Horton, 1984).
Sedimentologic data suggest arid periods in the late Pleistocene Kings Creek
catchment, and thus, droughts may explain the QML796 macropod mortality
patterns.
CARNIVORE MODIFICATION
The low abundance of tooth-markings on bone may partly reflect a taphonomic
bias wherein dry-type fractures, which are abundant in the assemblages,
possibly overprinted evidence of carnivore damage, thus rendering those bones
fragmentary and carnivore damage unidentifiable, and excluding them from
analysis. The abundance of V-shaped tooth markings with associated
depressed punctures, which are attributable to Thylacoleo carnifex (Horton and
Wright, 1981; Sobbe, 1990), indicates that T. carnifex was a major carnivore in
the catchment at the time of deposition. However, T. carnifex tooth-markings
were not recorded on fossil bone from the A1 horizon. All other tooth-markings
recorded may be related to feeding from other carnivorous species recorded in
the deposits including Megalania prisca, crocodylids, Sarcophilus laniarius,
Thylacinus cynocephalus and Dasyurus viverrinus.
175
Horton and Wright (1981) showed that Thylacoleo tooth-markings most
commonly occur on ribs, leading to the suggestion that Thylacoleo was a
specialist internal organ feeder. However, tooth-markings at site QML796 occur
on most skeletal elements, including dentaries, scapulae, ribs, vertebrae,
pelves, major limb bones, and metatarsals, suggesting a more generalist
feeding behaviour for Thylacoleo. Additionally, as carnivores typically gnaw on
the ends of limb bones, the high representation of tooth markings on the shafts
may indicate that the lower density, meatier limb bone ends were lost due to
carnivore activity. Regardless, overall levels of carnivore activity were not high.
ACCUMULATION PROCESSES
The most striking taphonomic observations from the assemblages include: 1)
low representation of post-cranial elements; 2) high degree of bone breakage;
3) low to moderate degree of abrasion of identifiable bones; 4) low rates of bone
weathering; and 5) low degree of articulated or associated specimens. Low
representation of certain post-cranial elements is most easily explained due to
hydrodynamic sorting. Based on the experimental studies of Voorhies (1969),
Dodson (1973), Behrensmeyer (1975) and Korth (1979), the high relative
abundance of skeletal elements that are transported in the middle to middle-late
categories of fluvial transport (Figure 22) and uncommon occurrence of
elements that are easily dispersed in flowing water indicates that extensive
sorting resulted in lag-type accumulations of both large and small-sized
mammals in each horizon. The low representation of crania and high numbers
of isolated molars and loss of molar tooth sites within each horizon may reflect
high susceptibility to breakage and destruction of crania. Such breakage is
consistent with sedimentologic data indicating deposition of the main
fossiliferous horizons during high velocity flow events. However, the velocity
required to transport skeletal material of small mammals is significantly lower
than that required to transport large mammals (Dodson, 1973), and such
elements may be transported as suspension load. Hence, differences in small
mammal skeletal representation also may be a function of differential
176
preservability and destruction of particular elements. The fragile nature of small
remains makes them highly vulnerable to destruction through weathering and
abrasion in comparison to remains of larger-sized mammals in similar
environments.
The hydraulic equivalence of larger bones in each main fossiliferous horizon
is estimated (after Behrensmeyer, 1975) to have been much greater than the
mean grain size (~2 mm) of the entombing sediments. Thus larger bones may
not have been transported far from a proximal death assemblage
(Behrensmeyer, 1975). The low degree of abrasion on identifiable bones also
reflects a short transport path. Weathering patterns of fossil bones (mostly
weathering stages 0-2) suggest little preburial exposure, although the exact
duration of bone exposure cannot be determined (Lyman and Fox, 1989), and
highly weathered bone may have been more susceptible to dry fracturing during
transport, thus biasing its distribution towards unrecognisable bone fragments.
The dominant dry or fossil-type fracture patterns of bones are not consistent
with breakage of fresh bone by trampling, carnivores, or hominids, but are
consistent with breakage during flood events.
Collectively, taphonomic data indicate that fossil material was accumulated
and transported into the deposit from the surrounding proximal floodplain, which
is consistent with the small Pleistocene catchment size (Price, 2005). Fossil
material was unlikely to have accumulated from distances greater than 20-25km
(Price, 2005). Additionally, although some material was undoubtedly reworked
from older deposits, the less abraded material is not likely to have been
reworked numerous times, and hence, probably dates from near the time of
deposition. The presence of articulated and associated remains indicates that at
least some components of the assemblage died within close spatial and
temporal proximity to the final site of deposition. Hence, analysed samples
broadly reflect a small Pleistocene catchment over averaged, but discrete,
sequential time intervals.
177
DISCUSSION
Several different types of taphonomic accumulations occur within the Kings
Creek catchment, and include deposits between the extremes of the channel-
lag and channel-fill (i.e., overbank) taphonomic modes of Behrensmeyer (1988).
Channel-lag accumulations are characterised by: 1) deposition in lower parts of
channels or erosional troughs, 2) deposition of sand and gravel, 3) well-sorted
bone accumulations, 4) some abrasion on bone, with bone pebbles common, 5)
high fragmentation of bone, 6) rare association of skeletal parts, and 7)
orientation of long bones with the palaeocurrent (Behrensmeyer, 1988). Such
deposits are allochthonous and may represent accumulation from throughout a
catchment (Behrensmeyer, 1988). Channel-fill modes are characterised by: 1)
deposition in the upper parts of channels or interfluves, 2) fine-grained sediment
matrix, 3) poor sorting of bone sizes, 4) lack of abrasion, 5) low fragmentation,
6) common association of skeletal parts, and 7) variable alignment with
palaeocurrent (Behrensmeyer, 1988). Bone is generally not transported over
great distances and the assemblage represents a more autochthonous deposit
with respect to the channel (Behrensmeyer, 1988). Sites QML796 (A7) and
QML1396 (B) both have lower channel-lag type accumulations (Behrensmeyer,
1988). The A4 and A1 horizons of QML 796 are somewhat intermediate
representing small interfluve channels and crevasse splays, mainly in overbank
settings. Deposits at QML783 are more similar to Behrensmeyer’s (1988)
channel-fill mode of accumulation.
Price and Sobbe (2005) suggested that sequential changes in fauna through
stratigraphy at site QML1396 was possibly related to changing habitat in the
Pleistocene Kings Creek catchment, and that those changes reflected
increasing aridity through time. The loss of diversity observed at QML796 also
suggests a shift in fauna over the time of deposition. In particular, some
megafaunal taxa (e.g., Diprotodon sp., Troposodon minor, Macropus agilis siva)
appear to have become locally extinct between horizons A7 and A1. However,
Kolmogorov-Smirnov two sample tests and bootstrapping analyses reject the
hypothesis that a simultaneous extinction event occurred after deposition of A1.
178
Hence, some megafauna became extinct below the A1 horizon whereas others
clearly persisted through the A1 horizon (e.g., Megalania prisca, Macropus titan,
Protemndon anak, P. brehus) only becoming extinct subsequently. Although
dating techniques may be equivocal for the site (Price & Sobbe, 2005), and
there are inadequate numbers of fossiliferous horizons to constrain rates of
species loss, the results clearly suggest minimally a two-stage local extinction of
megafauna. They are not consistent with a ‘blitzkrieg’ extinction model. Human-
induced cut markings and bone fracture patterns (e.g., spiral fractures) have not
been observed at QML796 or QML1396, and unconfirmed reports of cultural
artefacts in association with Darling Downs megafauna-bearing deposits
(Klaatsch, 1904) have not been verified subsequently. Charcoal is rare in the
deposits, suggesting that firing of the landscape, either anthropogenic or
natural, was insignificant in the region during the period of deposition. Thus
there is no direct evidence for human interactions with fauna in the Kings Creek
catchment.
One of the major factors that has lent support to the ‘blitzkrieg’ model of
extinction is that glacial-interglacial cycles have been operating for much of the
Pleistocene, yet most extinctions seem to be clustered near the time of the
latest Pleistocene glacial maximum, which is more or less coincident with the
arrival of humans in some areas (e.g., North America, Grayson & Meltzer, 2002;
Australia, O’Connell & Allen, 2004). However, in Queensland long-term records
from coastal lakes (e.g., 600ka on Fraser Island; Longmore & Heijnis, 1999)
suggest that although aridification was an ongoing process through the late
Pleistocene, different glacial maxima were associated with different degrees of
aridity. Significantly, the last glacial maximum was the most severe of those
recorded and was followed by very dry conditions in the Holocene (Longmore &
Heijnis, 1999). If those results are correct, it provides a rational explanation for
why extinctions might be concentrated around the last glacial maximum. The
last glacial maximum may have been uniquely severe in terms of aridity. The
arrival of humans may be coincidental, but there is no longer a requirement for
an additional external (i.e., human) agency to force latest Pleistocene
179
extinctions. Hence, as evidence of changing habitat types have been
documented at site QML1396, and sedimentologic and taphonomic data
suggest a seasonally arid climate (e.g., abundant calcrete formation in an
ephemeral fluvial setting, and drought-like macropod mortality patterns) at
QML796, the most parsimonious hypothesis is that megafaunal change at Kings
Creek was gradual and reflected changing habitats mostly likely associated with
intensifying aridification.
CONCLUSION
Site QML796 in Kings Creek catchment of the Darling Downs, Queensland
consists of late Pleistocene sediments that were deposited in both meandering
channel and overbank settings in an ephemeral fluvial environment. The site
contains three highly fossiliferous horizons, A7, A4, and A1, from base to top,
representing a laterally extensive point bar deposit, smaller, ephemeral
interfluve channels, and crevasse channel and splay deposits, respectively.
Calcrete, occurring both as reworked pebbles in channel lags and as
encrustations of bones in the uppermost horizons, suggests ongoing seasonally
arid conditions during the time of deposition. Despite being a fluvial deposit, the
site provides an ideal laboratory for examining temporal changes in local
Pleistocene faunas because: 1) the size of the Pleistocene catchment from
which taxa were sampled is well constrained and small (~500 km2), thus limiting
the degree to which samples could have been sourced by long distance
transport; 2) the site contains three stratigraphically sequential, highly
fossiliferous horizons with secure control on relative ages; and 3) the site was
excavated and processed in such a way as to target both large and small sized
taxa and to record relevant sedimentological data for taphonomic and
environmental analysis.
Results indicate decreasing taxonomic diversity for mammals in succeeding
horizons (ie., A7 through A1) that cannot be explained by sample bias or
sedimentological bias associated with fluvial accumulation or preservational
processes. The data are consistent with a local loss of certain megafaunal taxa
180
over the period of deposition (e.g., Diprotodon sp., Troposodon minor, Macropus
agilis siva). However, some megafaunal remains persisted to the youngest
horizon (e.g., Megalania prisca, Macropus titan, Protemnodon anak, P. brehus),
and Kolmogorov-Smirnov tests and bootstrapping analyses do not support the
hypothesis that all megafaunal taxa became extinct prior to deposition of the
youngest fossiliferous horizon. Hence, the data are consistent with a
progressive extinction of megafauna in the late Pleistocene Kings Creek
catchment. No evidence of human interaction with Pleistocene remains was
observed in the site or in other nearby sites (e.g., QML783 and QML1396). The
apparent progressive megafaunal extinction on the Darling Downs does not
support a sudden ‘blitzkrieg’ model resulting from human hunting. The gradual
demise of taxa at QML796 and evidence of seasonally arid conditions in the
section is most parsimoniously attributed to increasing aridity in southeastern
Queensland that culminated in an unusually severe arid interval associated with
the last glacial maximum (e.g., Longmore and Heijnis, 1999).
ACKNOWLEDGMENTS
We thank B. Cooke, I. Reid, S. Hocknull, B. Brooke, E. Reed, I. Williamson and
A. Cook for assistance and/or comments on earlier drafts of this manuscript. We
thank an anonymous reviewer, and especially D. Megirian, for significant and
constructive comments on an earlier version of this manuscript. R. Bell, S.
Hocknull, M. Ng, I. Sobbe, D. Sobbe, A. Sobbe, T. Sutton, and P. Tierney
provided tremendous assistance with excavations. P. Colquhon, P. Hamilton, G.
Jordan, L. Shipton, K. Spring, G. Todd, J. Wilkinson and countless volunteers
provided assistance in the preparation of fossil material. Additionally, D. Price,
J. Price, the Sobbe family, D. Turner, and M. Turner are thanked for their
continued support. This work was funded by the Queensland Museum and
Queensland University of Technology.
181
REFERENCES
ANDREWS, P. 1990. Owls, Caves and Fossils. Natural History Museum
Publications. London.
BADGLEY, C. 1986. Counting individuals in mammalian fossil assemblages from
fluvial environments. Palaios 1, 328-338.
BAIRD, R. F. 1991. The taphonomy of late Quaternary cave localities yielding
vertebrate remains in Australia, Chapter 10. In: Vickers-Rich, P., Monoghan,
J. M., Baird, R. F., & Rich, T. H. eds. Vertebrate Palaeontology of
Australasia, pp. 267-309. Pioneer Design Studio Pty Ltd and Monash
University Publications Committee, Melbourne.
BARNOSKY, A. D., KOCH, P. L., FERANEC, R. S., WING, S. L. & SHABEL, A. B. 2004.
Assessing the causes of late Pleistocene extinctions on the continents.
Science 306, 70-75.
BAYNES, A. 1999. The absolutely last remake of Beau Geste: yet another review
of the Australian megafaunal radiocarbon dates. Abstracts of the 6th
CAVEPS, July, 1997. Records of the Western Australian Museu,,
Supplement 57, 391.
BEHRENS, E. W. & WATSON, R. L. 1969. Differential sorting of pelecypod valves in
the swash zone. Journal of Sedimentary Petrology 39, 227-250.
BEHRENSMEYER, A. K. 1975. The taphonomy and paleoecology of Plio-
Pleistocene vertebrate assemblages east of Lake Rudolf, Kenya. Bulletin of
the Museum of Comparative Zoology 146, 473-578.
BEHRENSMEYER, A. K. 1978. Taphonomic and ecologic information from bone
weathering. Paleobiology 4, 150-162.
BEHRENSMEYER, A. K. 1982. Time resolution in fluvial vertebrate assemblages.
Paleobiology 8, 211-228.
BEHRENSMEYER, A. K. 1988. Vertebrate preservation in fluvial channels.
Palaeogeography, Palaeoclimatology, Palaeoecology 63, 183-199.
BEHRENSMEYER, A. K. 1990. Transport-hydrodynamics: bones. In: Briggs, D.E.G.
& Crowther, P.R. eds. Palaeobiology: a Synthesis. pp. 232-235. Blackwell
Scientific Publications, Oxford.
182
BEHRENSMEYER, A. K, STAYTON, C. T. & CHAPMAN, R. E. 2003. Taphonomy and
ecology of modern avifaunal remains from Amboseli Park, Kenya.
Paleobiology 29, 52-70.
BEST, J. L., ASHWORTH, P. J., BRISTOW, C. S. & RODEN, J. 2003. Three-
dimensional sedimentary architecture of a large, mid-channel sand braid
bar, Jamuna River, Bangladesh. Journal of Sedimentary Research 73, 516-
530.
BOUCOT, A. J., BRACE, W. & DEMAR, R. 1958. Distribution of brachiopod and
pelecypod shells in currents. Journal of Sedimentary Petrology 328, 321-
332.
BRENCHLEY, P. J. & NEWALL, G. 1970. Flume experiments on the orientation and
transport of models and shell valves. Palaeogeography, Palaeoclimatology
and Palaeoecology 7, 185-220.
BROWN, S. P. & WELLS, R. T. 2000. A middle Pleistocene vertebrate fossil
assemblage from Cathedral Cave Naracoorte South Australia. Transactions
of the Royal Society of South Australia 124, 91-104.
BURNEY, D.A. & FLANNERY, T.F. 2005. Fifty millennia of catastrophic extinctions
after human contact. Trends in Ecology and Evolution 20, 395-401.
CADÉE, G. C. 1968. Molluscan biocoenoses and thanatocoenoses in the Ria de
Arosa, Galicia, Spain. Zoologische Verhandelingen uitgegeven door het
Rijksmuseum van Natuulijke Historie te Leiden 95, 1-121.
CHAPLIN, R. E. 1971. The Study of Animal Bones From Archaeological Sites.
London. Seminar Press.
DODSON, P. 1971. Sedimentology and taphonomy of the Oldman Formation
(Campanian), Dinosaur Provincial Park, Alberta (Canada).
Palaeogeography, Palaeoclimatology, Palaeoecology 10, 21-74.
DODSON, P. 1973. The significance of small bones in paleoecological
interpretation. University of Wyoming Contributions to Geology 12, 15-19.
FIELD, J. & DODSON, J. 1999. Late Pleistocene megafauna and archaeology from
Cuddie Springs, south-eastern Australia. Proceedings of the Prehistoric
Society 65, 275-301.
183
FIELD, J. & FULLAGAR, R. 2001. Archaeology and Australian megafauna. Science
294, 7a.
GILL, E. D. 1978. Geology of the late Pleistocene Talgai cranium from S. E.
Queensland, Australia. Archaeology and Physical Anthropology in Oceania
13, 177-197.
GILLESPIE, R. 2002. Dating the first Australians. Radiocarbon 44, 455-472.
GRAYSON, D. K. & MELTZER, D. J. 2002. Clovis hunting and large mammal
extinction: a critical review of the evidence. Journal of World Prehistory
16,313-359.
HAMMER, Ø., HARPER, D. A. T., RYAN, P. D. 2001. PAST: Palaeontological
statistics software package for education and data analysis. Palaeontologica
Electronica 4(1), 9pp.
HAYNES, G. 1980. Evidence of carnivore gnawing on Pleistocene and Recent
mammalian bones. Paleobiology 6, 341-351.
HAYNES, G. 1983. A guide for differentiating mammalian carnivore taxa
responsible for gnawing damage to herbivore limb bones. Paleobiology 9,
164-172.
HECHT, M. 1975. The morphology and relationships of the largest known
terrestrial lizard, Megalania prisca Owen, from the Pleistocene of Australia.
Proceedings of the Royal Society of Victoria 87, 239-250.
HORTON, D. R. 1984. Red Kangaroos: last of the megafauna, Chapter 29. In:
Martin, P. S., Klein, R. G. eds. Quaternary Extinctions: A Prehistoric
Revolution, pp. 639-680. University of Arizona Press, Tuscon.
HORTON, D. R. 2000. The Pure State of Nature. Allen and Unwin, New South
Wales.
HORTON, D. R. & WRIGHT, R. V. S. 1981. Cuts on Lancefield bones: carnivorous
Thylacoleo, not humans, the cause. Archaeology in Oceania 16, 73-80.
JAMNICZKY, H. A., BRINKMAN, D. B., RUSSELL, A. P. 2003. Vertebrate microsite
sampling: how much is enough? Journal of Vertebrate Paleoentology 23,:
725-734.
184
JOHNSON, R. G. 1960. Models and methods for analysis of the mode of
formation of fossil assemblages. Geological Society of America, Bulletin 71,
1075-1088.
JOHNSTON, E. 1989. Human modified bones from early southern Plains Sites. In:
Bonnichsen, R. & Sorg, M.H. eds. Bone Modification, pp. 431-471.
University of Maine Center for the Study of the First Americans, Orono.
KLAATSCH, H. 1904. Übersicht über den bischerigen Verlauf und die
Errungenschaften seiner Reise in Australien bis Ende September 1904.
Zeitschrift für Ethnologies 1904, 211-213.
KLEIN, R. G. 1982. Age (mortality) profiles a means of distinguishing hunted
species from scavenged ones in Stone Age archaeological sites.
Palaeobiology 8, 151-158.
KORTH, W. W. 1979. Taphonomy of microvertebrate fossil assemblages. Annals
of the Carnegie Museum 48, 235-285.
KOS, A. M. 2003. Characterisation of post-depositional taphonomic processes in
the accumulation of mammals in a pitfall cave deposit from southeastern
Australia. Journal of Archaeological Science 30, 781-796.
LOFGREN, D. L., HOTTON, C. L. & RUNKEL, A. C. 1990. Reworking of Cretaceous
dinosaurs into Paleocene channel deposits, upper Hell Creek Formation,
Montana. Geology 18, 874-877.
LONG, J. & MACKNESS, B. 1994. Studies of the late Cainozoic diprotodontid
marsupials of Australia. 4. The Bacchus Marsh diprotodons- Geology,
sedimentology and taphonomy. Records of the South Australia Museum 27,
95-110.
LONGMORE, M. E., & HEIJNIS, H. 1999. Aridity in Australia: Pleistocene records of
palaeohydrological and palaeoecological change from the perched lake
sediments of Fraser Island, Queensland, Australia. Quaternary International
57/58, 35-47.
LYMAN, R. L. 1994. Vertebrate Taphonomy. Cambridge University Press,
Cambridge.
185
LYMAN, R. L. & FOX, G. L. 1989. A critical evaluation of bone weathering as an
indication of bone assemblage formation. Journal of archaeological Science
14, 293-317.
MARSHALL, L. G. 1989. Bone modification and “the laws of burial”. In:
Bonnichsen, R. & Sorg, M.H. eds. Bone Modification, pp 7-24. University of
Maine Center for the Study of the First Americans, Orono.
MARTIN, R. E. 1999. Taphonomy: A Process Approach. University Press,
Cambridge, United Kingdom.
MARTIN, A. J. 2000. Flaser and wavy bedding in ephemeral streams: a modern
and an ancient example. Sedimentary Geology 136, 1-5.
MARTIN-KAYE, P. 1951. Sorting of lamellibranch valves on beaches in Trinidad,
B. W. L. Geological Magazine 88, 432-434.
MIALL, A. D. 1996. The Geology of Fluvial Deposits: Sedimentary Facies, Basin
Analysis and Petroleum Geology. Springer-Verlag Incorportated, Berlin.
MOLNAR, R. E. & KURZ, C. 1997. The distribution of Pleistocene vertebrates on
the eastern Darling Downs, based on the Queensland Museum collections.
Proceedings of the Linnean Society of New South Wales 117, 107-133.
MOLNAR, R. E., WILKINSON, J. E. & SOBBE, I. H. 1999. Pleistocene fauna and
taphonomy at Ned’s Gully, eastern Darling Downs, Queensland. Abstracts
of the 6th CAVEPS, Perth, 7-11 July, 1997. Papers in Vertebrate
Palaeontology. Records of the Western Australian Museum 57, 412.
MURRAY, P. F. 1991. The Pleistocene megafauna of Australia, Chapter 24. In:
Vickers-Rich, P., Monoghan, J. M., Baird, R. F., & Rich, T. H. eds.
Vertebrate Palaeontology of Australasia, pp. 1071-1164. Pioneer Design
Studio Pty Ltd and Monash University Publications Committee, Melbourne.
MURRAY, P. F. 1998. Palaeontology and palaeobiology of wombats. In: Wells,
R.T. & Pridmore, P.A. eds. Wombats, pp. 1-33. Surrey Beatty & Sons,
Chipping North.
NAGLE, J. S. 1967. Wave and current orientation of shells. Journal of
Sedimentary Petrology 37, 1124-1138.
186
O’CONNELL., J. F. & ALLEN, J. 2004. Dating the colonisation of Sahul (Pleistocene
Australia-New Guinea): a review of recent research. Journal of
Archaeological Science 31, 835-853.
PAYNE, J. L. 2003. Applicability and resolving power of statistical tests for
simultaneous extinction events in the fossil record. Paleobiology 29, 37-51.
PIANKA, E. R. & SCHALL, J. J. 1981. Species densities of Australian vertebrates.
In: Keast, A. (ed.) Ecological biogeography of Australia, pp. 1676-1694. Dr.
W. Junk Publishers. The Hague.
PLEDGE, N. S. 1990. The upper fossil fauna of the Henshke Fossil Cave,
Naracoorte, South Australia. Memoirs of the Queensland Museum 28, 247-
262.
PRICE, G. J. 2002. Perameles sobbei, sp. nov. (Marsupialia, Peramelidae), a
Pleistocene bandicoot from the Darling Downs, south-eastern Queensland.
Memoirs of the Queensland Museum 48, 193-197.
PRICE, G. J. (2004) 2005. Fossil bandicoots (Marsupialia, Peramelidae) and
environmental change during the Pleistocene on the Darling Downs,
southeastern Queensland, Australia. Journal of Systematic Palaeontology 4,
347-356.
PRICE, G. J. & SOBBE, I. H. 2005. Pleistocene Palaeoecology and environmental
change on the Darling Downs, southeastern Queensland, Australia.
Memoirs of the Queensland Museum 51, 171-201.
PRICE, G. J., TYLER, M. J. & COOKE, B. N. 2005. Pleistocene frogs from the
Darling Downs, southeastern Queensland, Australia, and their
palaeoenvironmental significance. Alcheringa 29, 171-182.
REED, E. H. 2003. Vertebrate Taphonomy of Large Mammal Bone Deposits,
Naracoorte Caves World Heritage Area. Unpublished PhD thesis, Flinders
University of South Australia, Adelaide.
REED, E. H. & BOURNE, S. J. 2000. Pleistocene fossil vertebrate sites of the
South East region of South Australia. Transactions of the Royal Society of
South Australia 124, 61-90.
187
ROBERTS, R. G., FLANNERY, T. F., AYLIFFE, L. K., YOSHIDA, H., OLLEY, J. M.,
PRIDEAUX, G. J., LASLETT, G. M., BAYNES, A., SMITH, M. A., JONES, R. & SMITH,
B. L. 2001. New ages for the last Australian megafauna: Continent-wide
extinction about 46,000 years ago. Science 292, 1888-1892.
SHELDON, F. & WALKER, K. F. 1989. Effects of hypoxia on oxygen consumption
by two species of freshwater mussel (Unionacea: Hyriidae) from the River
Murray (Australia). Australia Journal of Marine and Freshwater Research 40,
491-500.
SHIMOYAMA, S., & HAMANO, T. 1990. The effect of oxygen-deficient water for the
molluscan thanatocoenosis in Hakata Bay. In: Robba, E. Ed. Proceedings of
the fourth symposium on Ecology and Paleontology of Benthic Communities,
Sorrento, 1-5 November, 1988, pp. 753-772. Museo Regionale di Scienze
Natural di Trino, Trino.
SHIMOYAMA, S. & FUJISAKA, H. 1992. A new interpretation of the left-right
phenomenon during spatial diffusion and transport of bivalve shells. Journal
of Geology 100, 291-304.
SHIPMAN, P. 1981. Life History of a Fossil: An Introduction to Taphonomy and
Paleoecology. Harvard University Press, Cambridge.
SIGNOR, P. W., III, & LIPPS, J. H. 1982. Sampling bias, gradual extinction patterns
and catastrophes in the fossil record. Geological Society of America Special
Papers 190, 291-296.
SOBBE, I. H. 1990. Devils on the Darling Downs- the tooth mark record. Memoirs
of the Queensland Museum 27, 299-322.
SPENCER, L. M., VAN VALKENBURGH, B. & HARRIS, J. M. 2003. Taphonomic
analysis of large mammals recovered from the Pleistocene Rancho La Brea
tar seeps. Paleobiology 29, 561-575.
STRAHAN, R. 1995. The Mammals of Australia. New Holland Publishers,
Australia.
TRUEMAN, C. N. G., FIELD, J. H., DORTCH, J., CHARLES, B. & WROE, S. 2005.
Prolonged coexistence of humans and megafauna in Pleistocene Australia.
Proceedings of the National Academy of Sciences 102: 8381-8385.
188
VAN HUET, S. 1999. The taphonomy of the Lancefield swamp megafaunal
accumulation, Lancefield, Victoria. Records of the Western Australian
Museum, Supplement, 57: 331-340.
VICKERS-RICH, P. 1991. The Mesozoic and Tertiary history of birds on the
Australian plate, Chapter 20. In: Vickers-Rich, P., Monoghan, J. M., Baird,
R. F., & Rich, T. H. eds. Vertebrate Palaeontology of Australasia, pp. 721-
808. Pioneer Design Studio Pty Ltd and Monash University Publications
Committee, Melbourne.
VILLA, P. & MAHEIU, E. 1991. Breakage patterns of human long bones. Journal of
Human Evolution 21, 27-48.
VOORHIES, M. R. 1969. Taphonomy and population dynamics of an early
Pliocene vertebrate fauna, Knox County, Nebraska. Contributions to
Geology, University of Wyoming. Special paper 1, 1-69.
WOODS, J. T. 1960. Fossiliferous fluviatile and cave deposits. In: Hill, D. &
Denmead A.K. eds. The Geology of Queensland, pp. 393-403. Journal of
the Geological Society of Queensland, Australia.
WROE, S., CROWTHER, M., DORTCH, J. & CHONG, J. 2003a. The size of the largest
marsupial and why it matters. Proceedings of the Royal Society of London B
series 271, 34-36.
WROE, S., FIELD, J., FULLAGER, R. & JERMIN, L. S. 2004. Megafaunal extinction in
the late Quaternary and the global overkill hypothesis. Alcheringa 28, 291-
331.
WROE, S., MYERS, T., SEEBACHER, F., KEAR, B., GILLESPIE, A., CROWTHER, M. &
SALISBURY, S. 2003b. An alternative method for predicting body mass: the
case of the Pleistocene marsupial lion. Paleobiology 29, 403-411.
189
190
Paper 5. PRICE, G.J. submitted. Late Pleistocene ecosystem dynamics,
habitat change, and species extinction on the Darling Downs, southeastern
Queensland, Australia. Palaeogeography, Palaeoclimatology,
Palaeoecology.
This chapter provides a comprehensive interpretation of late Pleistocene
Darling Downs palaeoenvironments, both at a single, well constrained
locality, and in a wider catchment perspective. An extensive dating analysis
complements the palaeoenvironmental component. Megafaunal extinction
hypotheses are proposed for the late Pleistocene Darling Downs. The paper
was submitted to Palaeogeography, Palaeoclimatology, Palaeoecology.
Contribution of authors
I collected, prepared and identified most of the material that was examined in
this paper (with additional support from others noted in the
Acknowledgements). I also supervised the laboring efforts of the volunteers
who assisted in the preparation of fossil material. Additionally, I conducted all
palaeoecological analyses, prepared grants for funding the radiocarbon
dating component of the study, and prepared the original and final
manuscripts for publication.
191
Late Pleistocene ecosystem dynamics, habitat change, and species extinction
on the Darling Downs, southeastern Queensland, Australia.
Gilbert J. Price
Queensland University of Technology, School of Natural Resource Science,
GPO Box 2434, Brisbane, Queensland, Australia, 4001. Ph: 61 7 3406 8350;
Fax: 61 7 3864 2330; Email: [email protected]
Abstract
Several late Pleistocene fossil localities in the Kings Creek catchment,
Darling Downs, southeastern Queensland, Australia, were examined in detail to
establish an accurate, dated palaeoecological record for the region, and to test
human versus climate change megafauna extinction hypotheses. Accelerator
Mass Spectrometry (AMS 14C) and U/Th dating confirm that the deposits are
late Pleistocene in age, but the dates obtained from the two methods are not in
agreement. A multifaceted palaeoecological investigation involving the
identification of specific species ecologies, ecological analogues to modern
habitats and communities, and measurements of diversity, revealed significant
habitat change between superposed assemblages of site QML796. The basal
fossiliferous unit contained species that indicate the presence of a mosaic of
habitats including riparian vegetation, vine thickets, scrubland, open and closed
woodlands, and open grasslands during the late Pleistocene. Those woody and
scrubby habitats contracted over the period of deposition so that by the time of
deposition of the youngest horizon, the creek sampled a more open type
environment. Current evidence suggests that habitat changed on the late
Pleistocene Darling Downs during the same timeframe that megafauna and
non-megafauna experienced geographic range shifts (i.e., local extinctions).
Those data are consistent with a climatic cause of megafauna extinction, and no
specific evidence was found to support human involvement in the local
extinctions or in forcing the climate change. Better dating of the deposits is
192
critically important as a secure chronology would have significant implications
regarding the continent-wide extinction of the Australian megafauna.
Keywords: megafauna, extinction, climate change, Pleistocene, Darling Downs,
Australia.
1. Introduction
The late Pleistocene witnessed the global extinction of almost 100 genera of
large-sized terrestrial vertebrates, commonly termed the ‘megafauna’ (animals
>44kg) (Barnosky et al., 2004). Such extinctions were most dramatic in America
and Australia where 72-88% of all megafaunal taxa were lost (Barnosky et al.,
2004). Debate over the causes for the extinctions has become particularly
polarised in recent years, with several leading hypotheses being pursued. The
most popular hypotheses suggest either: 1) an anthropogenic component to the
extinctions, via overhunting (‘blitzkrieg’ or attritional overkill) or indirect habitat
modification (‘sitzkreig’) (Martin, 1984; Flannery, 1990; Miller et al., 1999; 2005;
Alroy, 2001; Barnosky et al., 2004; Brook and Bowman, 2004; Fiedel and
Haynes, 2004; Johnson and Prideaux, 2004; Prideaux, 2004; Wroe et al., 2004;
Johnson, 2005); 2) naturally driven climatic change (Graham and Lundelius,
1984; Horton, 1984; 2000; Grayson and Meltzer, 2003; Guthrie, 1984; 2003;
Shapiro et al., 2004), or 3) a combination of both (Field and Dodson, 1999;
Barnosky et al., 2004; Trueman et al., 2005). However, there currently is no
universally accepted hypothesis capable of explaining Pleistocene terrestrial
megafaunal extinctions.
In many regions, understanding the relationship between late Pleistocene
human colonisation, climate change and species extinction has been impeded
by the lack of reliable dates (Barnosky et al., 2004). Development of late
Pleistocene chronologies is difficult in regions such as Australia, because many
important events may have occurred just outside the practical limits of
radiocarbon dating (Gillespie, 2002). Suggested dates for human arrival In
Australia range anywhere from >100 ka (Wang et al., 1998), > 60 ka (Roberts
193
and Jones, 1994; Thorne et al., 1999), and 50-42 ka (Fifield et al., 2001;
Gillespie, 2002; Bowler et al., 2003; O’Connell and Allen, 2004), with most of
those dates obtained from optically stimulated luminescence (OSL), electron
spin resonance (ESR), U/Th or radiocarbon dating techniques. Roberts et al.
(2001) and Miller et al. (1999; 2005) developed chronologies of megafaunal
extinction using radiocarbon, amino acid racemisation (AAR), U/Th, and OSL
methods and suggested that most Australian megafauna extinctions occurred
synchronously and continent-wide at ~46 ka. However, a growing body of
evidence is beginning to demonstrate that some species persisted beyond the
hypothesised extinction window of 46 ka (Field and Dodson, 1999; Trueman et
al., 2005). Those data mostly suggest overlaps of at least 15 ka between human
arrival and megafaunal extinction, and therefore have significant implications for
the causes of Australian late Pleistocene extinctions (Johnson, 2005; Trueman
et al., 2005). However, existing extinction hypotheses are based primarily on
temporal presence or absence patterns of megafaunal taxa and/or humans.
Data relating to megafaunal community population dynamics from integrated
stratigraphic successions from many of those late Pleistocene deposits are
absent or remain undocumented. Therefore, it is not possible to analyse the
response of specific local populations to human arrival and/or climate change.
Thus, the operational details of existing megafauna extinction hypotheses are
difficult to test.
The Darling Downs, southeastern Queensland, Australia, is emerging as an
area of major significance in the understanding of late Pleistocene megafauna
extinction. It is an extremely fossiliferous region that contains some of the
youngest megafauna deposits in Australia (Roberts et al., 2001). Previous OSL
and radiocarbon dates of Darling Downs megafauna deposits suggest burial
ages of 51-42 ka (Roberts et al., 2001; Price and Sobbe, 2005). Most Darling
Downs deposits are fluviatile in origin, occurring predominantly in exposed creek
channels within floodplains (Fig. 1), and contain mostly non-articulated remains.
Recent detailed investigations of stratigraphic, sedimentologic and taphonomic
aspects of several different fossil deposits in the Kings Creek catchment have
194
Fig. 1. Modern Kings Creek Catchment with heights (in metres) of surrounding peaks, the main
deposit (site QML796) and other deposits mentioned in the text (QML). GDR: Great Dividing
Range; KCC: Kings Creek Catchment; QML: Queensland Museum Locality.
established the formational processes and provenance of fossil material in
some of those sites (Molnar et al., 1999; Price, 2005; Price and Sobbe, 2005;
Price and Webb, in press). Although most deposits are dominated by small,
unidentifiable shards of bone, the small palaeocatchment size precludes long
distance transport (Price, 2005). Taphonomic analysis of identifiable material
suggested minimal reworking and that most identifiable bones were derived
from the proximal floodplain near the time of deposition (Price and Sobbe, 2005;
Price and Webb, in press). Several of the deposits also contain articulated and
associated remains of megafaunal species (Molnar et al., 1999; Price and
Webb, 2005, in press).
Previous palaeoecological analysis of site QML1396 in Kings Creek (Fig. 1)
suggested that habitats had changed along with a loss in faunal diversity
between deposition of the two fossiliferous horizons (Price and Sobbe, 2005).
However, accumulation bias could not be confidently ruled out as the cause of
diversity loss at the site. Subsequently, the sedimentology and taphonomy of
195
nearby site QML796, which contains three sequential fossiliferous horizons,
were documented, and in that case, decreasing diversity was shown not to
reflect sample or taphonomic bias (Price and Webb, in press). Additionally, the
temporal decline in diversity included the loss of some, but not all megafauna
taxa, over an extended time interval of deposition. The purpose of this paper is
to: 1) investigate more specifically, the population dynamics of the megafaunal
assemblages at QML796 so as to test the results from site QML1396; 2)
document a detailed palaeoecological record of the region throughout the late
Pleistocene; and 3) aid establishment of a detailed chronology of deposition by
introducing different dating methods.
2. Darling Downs deposits
The Pleistocene Kings Creek catchment represented a series of permanent
and ephemeral streams within a geographically small catchment (Price, 2005;
Price and Webb, in press). Site QML796 is located in the northern bank of
Kings Creek (Figs. 1 and 2) and its sedimentology and taphonomic
characteristics were described in detail by Price and Webb (in press). The
deposit contains both high-velocity lateral accretion deposits and low velocity
vertical accretion deposits. Three highly fossiliferous horizons (A7, A4 and A1
horizons; Fig. 2) form the focus of the present investigation. The basal
fossiliferous unit, ‘A7 horizon’, represents lag and bar deposit in a main channel.
Upwardly, the unit passes into clay-silt-rich overbank deposits. The middle ‘A4
horizon’ represents minor stacked channel elements with deposition occurring in
small tributaries on the interfluve during high rainfall periods. The ‘A1 horizon’ is
the uppermost unit, and its geometry indicates crevasse channel and splay
deposition on the floodplain adjacent to the channel belt (Price and Webb, in
press). Deposition of low velocity, vertically accreted sediments occurred
between each of the main fossiliferous units. Taphonomic data suggest that
each main fossiliferous unit had the potential to sample similarly sized taxa. The
preservation of fossil material in the major horizons ranges from abraded, highly
mineralised, unidentifiable bone ‘pebbles’, to complete, pristinely preserved
196
Fig. 2. Measured stratigraphic column of sites QML796 and QML1396 with dates (ka) obtained
from AMS 14C and U/Th methods.
skeletal elements. Collectively, the taphonomic data suggest that most of the
identifiable material was accumulated and transported into the deposit from the
surrounding proximal floodplain. Faunal lists compiled for analysis in this paper
use only those taxa that are represented by unabraded material, and hence, are
unlikely to have been significantly transported or reworked.
Most other deposits in the catchment occur upstream from site QML796 (Fig.
1). Site QML1396 is located in the southern bank of Kings Creek (Fig. 1; Price
and Sobbe, 2005). The basal fossiliferous unit (Horizon B) is litho- and
biostratigraphically correlated to the A7 horizon of QML796 (Fig. 2; Price &
Webb, in press). The deposit passes upwards into overbank (crevasse splay)
deposits. Due to differential modes of accumulation within QML1396 and
interpreted sampling bias of the Pleistocene channel, comparisons between
faunal assemblages of the different horizons are limited (Price and Sobbe,
2005). Stratigraphic successions for most other deposits in the Kings Creek
catchment are poorly known (e.g., sites QML100, QML783; QML872, and
QML913; Fig. 1).
197
3. Methods
3.1. Sampling procedure
Fossils were collected both by in-situ and by bulk removal of sediment for
sieving to target small-sized specimens. Sediment was washed through graded
sieves ranging from 10mm to 1mm, and small bones were sorted following
techniques described in Andrews (1990). Additional details regarding the
excavation of the deposit are given in Price and Webb (in press). Identification
of the fossil material was made by comparative morphological and
morphometrical techniques. Species MNI (minimum number of individuals) for
each main fossiliferous unit was determined by Price and Webb (in press). Taxa
represented by abraded material were excluded from subsequent
palaeoecological analyses, as that material has a higher likelihood of being
reworked from older deposits.
Higher systematics follow Beesley et al. (1988) for molluscs, Glasby et al.
(1993) for amphibians and reptiles, and Aplin and Archer (1987) for mammals.
Body weight estimates of taxa were taken from Strahan (1995) and Cogger
(2000) for extant taxa; and Hecht (1975), Murray (1991), Wroe (2002) and Wroe
et al., (2003a, b) for extinct megafauna.
3.2. Ecological analogies to modern habitats
Andrews et al. (1979) demonstrated that the community structure of mammal
communities from similar habitat types is consistent, even where a comparison
of taxa between habitat types indicates few or no species in common. Andrews
et al. (1979) suggested that habitats of mammalian communities can be
predicted on the basis of their ecological diversity. Hence, establishing the
community structure of modern mammal faunas from particular habitats and
subsequent comparison to the community structure of fossil mammal
assemblages has predictive value for assessing palaeohabitats (Andrews et al.,
1979). Certain aspects of community structure of modern Australian mammalian
faunas were compared to the interpreted community structure of fossil
198
mammals from each of the three main fossiliferous horizons of QML796. The
methodology utilised is based largely on work by Andrews et al. (1979) for
African faunas. Faunal lists of twelve modern Australian faunas were compiled
and examined for each of three main habitat types- closed woodland/rainforest,
open woodlands/mesic, and low open woodlands/grasslands (Table 1). The
Table 1. Vegetative characteristics of modern habitat types.
Locality Vegetation References (vegetation
and/or fauna)
Uluru, Northern Territory Low mulga scrublands, spinifex
grasslands
Reid et al., 1993
Gibson Desert, Western
Australia
Low open scrubland, hummock
grasslands
MacKenzie and Burbidge,
1979; Friend, 1990
Victoria Desert, Western
Australia
Low open woodlands, hummock
grasses on sand plains
MacKenzie and Burbidge,
1979; Friend, 1990
Little Sandy Desert, Western
Australia
Low open woodlands, hummock
grasslands, spinifex sandplains
MacKenzie and Burbidge,
1979; Friend, 1990
Brigalow Belt (Vegetation group
7), Queensland
Dry to open woodland with grass
or heath understorey
McFarland et al., 1999
Darling Downs, Queensland Open grasslands on floodplain,
woodlands with grassy and
shrubby understorey closer to
hillsides
Van Dyck and Longmore,
1991; Fensham and
Fairfax, 1997
Texas, Queensland Savannah woodlands Archer, 1978
Bungle Bungle, Western
Australia
Woodlands, open forest, low
open woodlands, open
scrublands
Woirnarski, 1992
Atherton uplands, Queensland Closed, wet sclerophyll forest Williams et al., 1996
Thornton lowlands,
Queensland
Closed, wet sclerophyll forest Williams et al., 1996
Windsor uplands, Queensland Closed, wet sclerophyll forest Williams et al., 1996
Townsville lowlands,
Queensland
Closed, wet sclerophyll forest Williams et al., 1996
modern localities were selected from a variety of different biogeographic regions
and climatic zones and reflect datasets with sound coverage. Several aspects of
199
community structure, including feeding adaptation, locomotory, and life habit
data, were derived from each of the three main habitat types. Bats were
excluded from the analysis of the modern faunas as they are unrepresented in
the QML796 assemblage (following Andrews et al. 1979). Additionally, there
have been several extinctions of small-sized mammals in Australia since
European settlement, particularly in semi-arid and arid environments. Hence,
modern faunas were selected that include knowledge of species present during
the historic period both at the time of and after European settlement. Feeding
adaptation data from the modern faunas were based on six main feeding types.
The categories are fairly broad and were limited to insectivores, frugivores,
browsers, grazers, carnivores and omnivores. Locomotory data are broadly
constrained to reflect the proportion of semi-aquatic, fossorial, terrestrial
quadruped (including cursorial, subcursorial, mediportal and graviportal taxa),
saltatorial, scansorial and arboreal species within each modern habitat type. Life
habit data are based on a species’ most active portion of a 24 hour period and
reflect the proportions of species representing diurnal-crepuscular, crepuscular-
nocturnal and nocturnal habits.
The ecological aspects of modern mammalian species were derived from
Strahan (1995). Ecological aspects of extant taxa that occur as fossils in the
QML796 assemblage were drawn by analogy to extant populations. Ecologies
of fossil taxa were largely derived from Bartholomai (1973; 1975), Murray (1984)
and Flannery (1990).
The percentage of taxa representing each category of each ecological aspect
was calculated at the site level, and means were calculated for each main
habitat type. Pearson bivariate correlation statistics were calculated to test the
similarity between fossil assemblages and 1) individual modern habitat
localities, and 2) means of modern communities, using the SPSS © statistical
package. Correlations were considered to be significant at the 95% confidence
level.
200
3.3. Diversity estimates
The ability to quantify diversity is an important tool when attempting to
understand community structure (Vermeij and Leighton 2003). There are
several different ways to estimate the diversity of an assemblage or community.
One of the most simple diversity estimates is by comparison of the total number
of species recorded between assemblages. However, such estimates of species
richness do not take into account several major aspects of diversity including
equability or evenness of the relative abundance of species, or heterogeneity of
the fauna (Willig, 2003). Several indices have been developed that attempt to
take into account species abundance and evenness, and may provide important
information about rarity and commonness of particular species within a
community or assemblage (Buzas and Hayek, 2005). Diversity estimates for site
QML796 were based on Simpson, Shannon-Weiner, Pielou, and Whittaker
diversity indices, and MacArthur rank abundance models for terrestrial species
from each of the main fossiliferous horizons.
The Simpson’s heterogeneity index (D) is calculated by the formula:
( )( )
1
11
=
��
���
�
−−
=�
i
NNnn
D
s
ii (1)
where s is the total number of species, ni is the number of individuals i in the
sample, and N is the total number of species in the sample. D ranges between 0
and 1, and is larger for samples with less heterogeneity. That relationship is
neither logical nor intuitive, so the relationship is inverted with D being
subtracted from 1 so that lower values reflect less heterogeneity (Rose, 1981).
The Shannon-Weiner heterogeneity index (H') is among the most widely
used indices of diversity and is calculated by the formula:
1
ln'
=
−= �i
ppH
s
ii (2)
201
where s is the total number of species in a sample and p is the frequency of the
ith species. The index is primarily used as a measure of heterogeneity or mixed
diversity, but also reflects evenness.
The evenness component of heterogeneity is measured using several
indices. Among the most simple is Pielou’s evenness index calculated by the
formula:
sH
Jln
'= (3)
The calculation is derived from the result of H' and number of species in the
sample (s).
An additional index of evenness is the Whittaker index (E), which is
calculated using the formula:
( )spps
Eloglog 1 −
= (4)
where s is the number of species, pi is the frequency of the most common
species, and ps is the frequency of the rarest species.
Each diversity index has limitations, but the indices can be highly informative
regarding community structure (Buzas and Hayek, 2005).
Diversity and evenness may also be estimated using hypothetical models of
rank abundance of species within a given community or assemblage. Two main
models of the hypothetical distribution of species within a given community were
developed by MacArthur (1957; 1960). The ‘dependent model’ (as hypothesis I
in MacArthur, 1957) predicts that the relative abundance of any species is
dependent on the relative abundance of all other species within a fauna. Thus,
the relative abundance �
��
mN r of the rth rarest species is calculated by the
formula:
( )1
111
=+−
= �
iinnm
Nr
r
(5)
202
where m is the total number of individuals in a fauna, n is the total number of
species in the fauna, and Nr is the abundance of the rth rarest species. Here, m
is the total MNI and Nr is the MNI of the rth species. If relative abundance is
plotted against the logarithm of the rank abundance, the resulting curve is
nearly linear. MacArthur (1957) demonstrated that certain bird communities
from homogeneously diverse tropical and temperate forests fit the dependent
model hypothesis.
The ‘independent model’ (as hypothesis II of MacArthur, 1957) predicts that
the relative abundance of species r is independent of all other species within a
given fauna. The relative abundance mN r of the rth rarest species is calculated
by the formula:
( ) ( )( )n
rnrnmN r −−+−
=1
(6)
where n is the number of species in the fauna and r is the rank abundance of
species r. Here, rank is based on the abundance rather than rarity such that
1+−= rni . The model predicts that the common species are commoner and
rare species are rarer than that predicted by the ‘dependent model’. Hutchinson
(1961) observed independent model-type distributions of diatoms, arthropods
and plankton species in heterogeneous environments.
3.4. Dating
Samples of bivalves (Velesunio ambiguus), charcoal and bone were
submitted to ANSTO (Australian Nuclear Science and Technology Organisation;
Lawson et al. 2000) for the purpose of accelerator mass spectrometry (AMS) 14C dating. Only complete, conjoined bivalves were submitted for dating, as they
are unlikely to have been reworked from older units. V. ambiguus, like most
Unionoidea, have the ability to burrow (Walker, 1981). Hence, it is possible that
individuals selected for dating could have burrowed into sediment older than
that in which they lived. However, at site QML796, stratigraphic and
sedimentologic sequences are preserved intact and there is no evidence of
203
extensive burrowing of bivalves (Price and Webb, in press). Additionally,
bivalves selected for dating included only those that were lying with their valves
horizontal in the sediment and not in ‘growth’ or ‘burrowing’ positions (i.e.,
valves in vertical positions). Those individuals are presumed to have been
deposited in that position and were unlikely to have burrowed into older
sedimentary horizons.
Selection of bivalve and charcoal samples submitted for dating followed the
criteria of Meltzer and Mead (1985): samples were collected from stratigraphic
horizons containing megafauna and other smaller-sized taxa that are entirely
capped on lower and upper layers by different sediments. Results obtained from
AMS 14C dating of bivalves and charcoal should indicate the approximate time
of deposition.
Bone samples from sites QML796 and QML1396 were submitted to
ACQUIRE (Advanced Centre for Queensland University Isotope Research
Excellence, University of Queensland) for U/Th dating. Bone submitted for
dating using both AMS 14C and U/Th dating methods included near complete
megafauna crania and dentaries, isolated teeth, and complete post-cranial
elements. Specimens selected were well-preserved, relatively complete, and
unabraded. Hence, the selection criteria targeted fossil material that was
particularly well preserved, and highly unlikely to have been transported far or
reworked. U-series dating is based on the premise that U is taken up from the
environment by bone apatites that scavenge U, but exclude Th, during
diagenesis. The age is calculated by determining the amount of 230Th that was
produced by the decay of 238U (via intermediate isotope 234U). Since bones are
open systems for uranium, in most cases the U/Th dates represent the mean
ages of the U-uptake history and thus the minimum ages of deposition
(Simpson and Grün, 1998; Thorne et al., 1999; Zhao et al., 2001). Meltzer and
Mead (1985) considered that direct dating of fossil bone commonly represents a
‘strong’ association between fauna and deposition time and is desirable for
securely dating fossil assemblages.
204
4. Results
4.1. Species
Over 50 taxa were identified at QML796, ranging from molluscs (freshwater
and terrestrial), teleosts, anurans, chelids, squamates, aves, monotremes,
marsupials and placentals (Tables 2-3). The most common groups recovered
were freshwater molluscs, in particular, the thiararid gastropod Thiaria
(Plotiopsis) balonnensis, represented by several thousands of individuals from
each stratigraphic horizon. The most common terrestrial vertebrates recovered
from each horizon were murids, being represented mainly by isolated teeth.
Small-sized taxa (i.e., <1kg) dominate each main fossiliferous horizon (Fig. 3).
Terrestrial taxa weighing in excess of 100 kg were proportionately most
common in A7 and least common in A1 (Fig. 3).
Fig. 3. Body weight distributions of terrestrial vertebrate taxa recorded from site QML796.
Several extant species recorded in the deposit have modern populations that
no longer occur sympatrically. Such associations are regarded as non-analogue
species pairs (Stafford et al., 1999). Price (2005) identified non-analogue
species associations of bandicoots from the A7 horizon (as ‘the main bandicoot
fossiliferous horizon’ in Price, 2005). Additional non-analogue species pairings
also were identified in the other main fossiliferous horizons (Tables 4-6).
Population sizes of several taxa appear to have decreased over the period of
deposition (Figs. 4, 10). For example, within Macropodinae (kangaroos),
population sizes of most species declined over the period of deposition.
Troposodon minor declined from A7 (N = 14, 1.8%) to A4 (N = 10, 0.7%), and
was not sampled in A1. Macropus agilis siva declined from A7 (N = 18, 2.4%) to
205
A4 (N = 18, 1.2%), and was not sampled in A1. Similar trends were observed for
the diprotodontoid, Diprotodon sp., whose populations declined from A7 (N =
26, 3.4%) to A4 (N = 42, 2.9%), and was not sampled in the A1 horizon.
Table 2. Distribution of non-mammalian taxa within each main fossiliferous horizon at QML796,
with their preferred or inferred habitat preferences.
Species A
7
A4
A1
Fres
hwat
er
Rip
aria
n
Vin
e th
icke
ts
Scr
ubla
nd
Clo
sed
woo
dlan
d
Ope
n w
oodl
and
Ope
n/
gras
slan
d
Velesunio ambiguus x x x x
Corbicula (Corbiculina) australis x x x x Thiara (Plotiopsis) balonnensis x x x x
Gyraulus gilberti x x x x Glyptophysa gibbosa x x
Paralaoma caputspinulae x x x x Coencharopa sp. x x x x
Gyrocochlea sp. x x x x Strangesta sp. x x
Austrosuccinea sp. x x x x x
Teleost gen. et. sp. indet. x x x x Limnodynastes tasmaniensis x x x x x x x x
L. sp. cf. L. spenceri x x Kyarranus sp. x x x
Chelid gen. et sp. indet. x x x x Tympanocryptis lineata x x x x
Physignathus leseurii x x x x x ‘Sphenomorphus Group’ sp. 1 x x x x x x x x x
‘Sphenomorphus Group’ sp. 2 x x x x x x x x x
‘Sphenomorphus Group’ sp. 3 x x x x x x x Tiliqua rugosa x x x x x x
Varanus sp. x x x x x x x x x Megalania prisca x x x x x x
Elapid gen. et sp. indet. x x x x x x x x x Anatid sp. A x x
Anatid sp. B x x
Gallinula morterii x x Dromaius novahollandiae x x x x x
206
Table 3. Distribution of mammalian taxa within each main fossiliferous horizon at QML796, with
their preferred or inferred habitat preferences.
Species
A7
A4
A1
Fres
hwat
er
Rip
aria
n
Vin
e th
icke
ts
Scr
ubla
nd
Clo
sed
woo
dlan
d
Ope
n w
oodl
and
Ope
n/
gras
slan
d
Ornithorhyncus anatinus x x x
Tachyglossus sp. x x x x x x
Zaglossus sp. x x x x x x
Sminthopsis sp. x x x x x x x x
Antechinus sp. x x x
Dasyurus viverrinus x x x x x
Sarcophilus laniarius x x x
Perameles sobbei x x x ? ? ? ? ?
P. bougainville x x x
P. nasuta x x x x x x x x
Isoodon obesulus x x x x x
Vombatid indet. x x x x
Phascolonous gigas x x x
Palorchestes azael. x x
Palorchestes sp. x x
Diprotodon sp. x x x x
Zygomaturus trilobus x x
Thylacoleo carnifex x x x
Bettongia sp. x x x
Aepyprymnus rufescens x x
Troposodon minor x x x
Macropus agilis siva x x x
M. titan x x x x x
Protemnodon brehus x x x x x
Pr. roechus x x x x
Pr. anak x x x x x
Pseudomys gracilicaudatus x x
Ps. australis x x x x
Pseudomys sp. A x x x x
Rattus sp. x x x x x x x x
Hydromys chrystogaster x x x x x
207
Generally, A7 contains the highest proportion of taxa that are now extinct
(predominantly megafauna) and lowest proportion of taxa that are extant in the
region (Fig. 5). Conversely, A1 contains the lowest proportion of extinct taxa and
highest proportion of extant taxa.
Demonstrating faunal declines in other megafaunal and non-megafaunal taxa
is difficult owing to low numbers of individuals. However, broadly speaking, A7 is
the only unit that sampled megafaunal taxa, such as Phaslcolonous gigas,
Table 4. Non-analogue species pairings from the A7 horizon at QML796. For example, extant
populations of species 7 (Isoodon obesulus) occur allopatrically with species 3 (Kyarranus sp.)
and species 10 (Pseudomys gracilicaudatus), but fossil populations of those species occur
sympatrically within A7.
Species no. Species Modern allopatric species pairing
1 Tympanocryptis lineata 3, 4, 6, 8, 10, 11
2 Tiliqua rugosa 3, 4, 6, 10, 11
3 Kyarranus sp. 1, 2, 4, 5, 7, 9, 11
4 Dasyurus vivverinus 1, 2, 3, 5, 6, 9, 10, 11, 12
5 Perameles bougainville 3, 4, 8, 10, 11
6 Perameles nasuta 1, 2, 4, 9
7 Isoodon obesulus 3, 10
8 Vombatus sp. 1, 5, 9, 11
9 Pseudomys australis 3, 4, 6, 8, 10, 11
10 Pseudomys gracilicaudatus 1, 2, 4, 5, 7, 9
11 Rattus sordidus 1, 2, 3, 4, 5, 8, 9
12 Rattus tunneyi 4
Palorchestes sp. (see also Price and Hocknull, 2005), P. azael, and
Zygomaturus trilobus. For small-sized terrestrial groups such as peramelids
(bandicoots), only two species, Perameles sobbei and Pe. nasuta, were
represented in the entire depositional sequence. In contrast, populations of Pe.
bougainville and Isoodon obesulus were represented only in the older units,
albeit in low numbers. Similarly, populations of most murids (rats and mice)
208
Table 5. Non-analogue species pairings of extant species from the A4 horizon at QML796
Species
no.
Species Modern allopatric species
pairing
1 Limnodynastes spenceri 4, 5, 6, 7, 8, 9, 10, 12
2 Tympanocryptis lineata 4, 5, 6, 7, 9, 10, 12
3 Tiliqua rugosa 4, 5, 7, 9, 10, 12
4 Ornithorhyncus anatinus 1, 2, 3, 11
5 Dasyurus vivverinus 1, 2, 3, 7, 10, 11, 12, 13
6 Antechinus sp. 1, 2, 11, 12
7 Perameles nasuta 1, 2, 3, 5, 11
8 Isoodon obesulus 1, 10
9 Vombatus sp. 1, 2, 3, 11, 13
10 Aepyprymnus rufescens 1, 2, 4, 12, 12
11 Pseudomys australis 4, 5, 6, 7, 9, 10, 12
12 Rattus sordidus 1, 2, 3, 5, 6, 9, 11
13 Rattus tunneyi 5
fluctuated over the period of deposition, with Pseudomys gracilicaudatus
populations being unrepresented post-deposition of A7. Interestingly, those taxa
represented in the basal fossil unit (A7) that were not also sampled in the
youngest horizon (A1), do not occur on the modern Darling Downs.
Table 6. Non-analogue species pairings of extant species from the A1 horizon at QML796
Species no. Species Modern allopatric species pairing
1 Tympanocryptis lineata 3, 4, 5, 6, 8
2 Tiliqua rugosa 3, 4, 5, 6, 8
3 Gallinula morterii 1, 2, 5, 7, 8, 9
4 Dasyurus vivverinus 1, 2, 5, 7, 8, 9
5 Perameles nasuta 1, 2, 3, 4, 7
6 Vombatus sp. 1, 2, 8
7 Pseudomys australis 3, 4, 5, 8
8 Rattus sordidus 1, 2, 3, 4, 6, 7
9 Rattus tunneyi 3, 4
209
Fig. 4. Proportional relative abundance of selected taxa from site QML796. A. Peramelids
(bandicoots); B. Vombatids (wombats) and diprotodontoids; C. Macropods (kangaroos); D.
Murids (rats and mice).
Several taxa clearly persisted in each stratigraphic unit of the deposit.
Populations of the murid, Ps. australis, exhibit a decline over the period of
deposition, but are still represented in the A1 horizon (A7: N = 18, 2.7%; A4: N =
20, 1.4%; A1: N = 4, 0.6%). Macropus titan and Protemnodon anak appear to
have suffered dramatic population declines, but were sampled in the A1 horizon
(Figs. 4, 10). Other megafaunal taxa such as Megalania were abundantly
represented in each stratigraphic horizon (A7: N = 52, 6.8%; A4: N = 51, 3.5%;
A1: N = 58, 8%; Fig. 10) (Price and Webb, in press).
Fig. 5. Present conservation status of taxa recorded from site QML796.
210
Taxa frequenting freshwater habitats are well represented in each
fossiliferous horizon (Tables 2-3). A7 horizon contains the highest number of
taxa that may occur exclusively in closed and scrubby vine-thicket habitats (e.g.,
Coencharopa sp., Gyrococlea sp., Paralaoma caputspinulae, Kyarranus sp.,
Isoodon obesulus, Perameles bougainville), and open woodlands (e.g.,
Sarcophilus laniarius, Palorchestes spp., Zygomaturus trilobus, Thylacoleo
carnifex, Troposodon minor, Macropus agilis siva, and Pseudomys
gracilicaudatus; Tables 2-3). A1 horizon contains the lowest proportion of taxa
that are restricted to specific habitats (Tables 2-3).
4.2. Ecological dynamics
4.2.1. Feeding adaptations
Feeding adaptation components of modern faunas were graphically (Fig. 6)
and statistically compared to those of fossil horizons and suggests that both A7
(σ = 0.008) and A4 (σ = 0.050) were statistically similar to modern
woodland/mesic type habitats. At site level, A7 was significantly similar to the
woodlands/mesic habitats of Texas (σ = 0.030) and Brigalow Belt (σ = 0.027)
and approached significance with the Bungle Bungle fauna (σ = 0.089). A4 was
significantly correlated to the Texas region (σ = 0.036) and approached
significance with the Bungle Bungle fauna (σ = 0.096). Additionally, A4 also has
statistically significant similarity to the open habitat of the Victoria Desert (σ =
0.041). A7, A4 and modern woodland/mesic habitats are characterised by a
high proportion of grazers, moderate proportions of insectivores, browsers,
carnivores and omnivores, and low proportions of frugivores (Fig. 6).
The A1 horizon fauna was not significantly correlated to the means of the
feeding adaptation categories of any modern habitat type. However at site level,
A1 was significantly correlated to the woodland/mesic habitats of the Texas
region (σ = 0.013) and approached significance to the Bungle Bungle fauna (σ =
0.079). Additionally, A1 was significantly correlated to open habitat of the
211
Fig. 6. Proportion of feeding adaptation categories for the means of modern communities and
interpreted for fossil assemblages of site QML796. A. Modern open habitats; B. Modern
woodlands/mesic habitats; C. Modern closed woodlands; D. A7 Horizon; E. A4 Horizon; F. A1
Horizon.
Victoria Desert (σ = 0.036), and approached significance with the Little Sandy
Desert (σ = 0.094). Hence, the A1 faunal assemblage appears to share
components of both modern woodlands/mesic habitats and open habitats (Fig.
6). A1 is similar to modern habitats with very low proportions of frugivores and
browsers, but differs markedly by having comparatively low proportions of
insectivores (Fig. 6). A1 is similar to modern woodlands and mesic habitats with
high proportions of grazers, and moderate, proportions of omnivores (Fig. 6).
Within the fossil assemblages, an obvious trend exists with a proportional
decrease of browsing taxa relative to a steady increase of grazing taxa over the
period of deposit (Fig. 6). Browsing taxa of the A7 horizon are dominated by
large-sized marsupials including diprotodontoids (Palorchestes azael and
Palorchestes spp. ~300 kg, Diprotodon sp. ~2,700 kg, and Zygomaturus trilobus
~500 kg) and macropodines (Troposodon minor ~45 kg). The grazing marsupial
taxa are generally smaller in size and include large and small vombatids
(Phascolonous gigas ~150 kg, and Vombatus sp. ~30 kg), and macropodines
(Macropus agilis siva ~25 kg, M. titan ~85 kg, Protemnodon anak ~50 kg, Pr.
brehus ~75 kg, and Pr. roechus ~85 kg). By the time of deposition of A4, three
of those browsing taxa, Pa. azael, Palorchestes sp. and Z. trilobus, and one
grazing taxon, Ph. gigas, were unrepresented. By the time of deposition of the
212
youngest horizon, A1, browsing taxa are completely unrepresented (Fig. 6). A1
Large-sized herbivores are represented solely by grazing taxa, M. titan, Pr. anak
and Pr. brehus. Hence, those data suggest a differential pattern of extinction for
browsing and grazing megafaunal species.
4.2.2. Locomotory adaptations
None of the fossiliferous units significantly correlate to the means of the
locomotory adaptation categories of any modern habitat type. At site level, A7
does not significantly correlate to any single modern habitat. The A4
assemblage approached significance with the mean of the modern
woodland/mesic habitats (σ = 0.080), and A4 correlates to the woodland/mesic
habitats of Texas (σ = 0.018) and approaches significance with Bungle Bungle
(σ = 0.095). A1 significantly correlates to the mesic habitat of the Bungle Bungle
fauna (σ = 0.032).
Fig. 7. Proportion of locomotory adaptation categories for the means of modern communities and
interpreted for fossil assemblages of site QML796. A. Modern open habitats; B. Modern
woodlands/mesic habitats; C. Modern closed woodlands; D. A7 Horizon; E. A4 Horizon; F. A1
Horizon.
Each horizon is similar to modern woodlands in having relatively high
proportions of terrestrial quadruped and saltatorial species (Fig. 7). The A7
assemblage has the highest proportion of terrestrial quadruped species,
including megafauna taxa such as Palorchestes spp., Diprotodon sp.,
Zygomaturus trilobus, Thylacoleo carnifex, and small-sized mammals including
213
Perameles bougainville, P. sobbei, P. nasuta, and Isoodon obesulus.
Additionally, each horizon shows similarities to modern open habitats in having
low proportions of scansorial and arboreal species (Fig. 7). However, they differ
markedly from such habitats in having a lower representation of fossorial taxa.
High proportions of fossorial taxa are characteristic of modern open habitats
(Fig. 7). However, a marked trend in the increase of fossorial taxa over the
period of deposition is evident (Fig. 7).
4.2.3. Life habits
Life habit adaptation components of modern faunas were graphically (Fig. 8)
and statistically compared to those of fossil horizons and suggest that both A7
(σ = 0.047) and A4 (σ = 0.007) were statistically similar to modern
woodland/mesic type habitats. At site level, A7 approached significance to the
open habitat of the Victoria Desert (σ = 0.091), and woodland/mesic habitats of
the Brigalow Belt (σ = 0.091). A4 does not correlate significantly to any single
Fig. 8. Proportion of life habit categories for the means of modern communities and interpreted
for fossil assemblages of site QML796. A. Modern open habitats; B. Modern woodland/mesic
habitats; C. Modern closed woodlands; D. A7 Horizon; E. A4 Horizon; F. A1 Horizon.
modern habitat analysed. A1 correlates to the open habitat of the Victoria
Desert (σ = <0.001), and woodland/mesic habitats of the Brigalow Belt (σ =
<0.001) and Bungle Bungle (σ = 0.028). Additionally, A1 approaches
significance to the mesic habitats of the modern Darling Downs (σ = 0.058) and
214
closed habitat of the Townsville lowlands (σ = 0.087). Modern closed and open
habitats are very similar to each other in having high proportions of nocturnal
taxa, moderately low proportions of crepuscular taxa, and low proportions of
diurnal species (Fig. 8). Generally, the fossil assemblages most closely
resemble modern woodland/mesic habitats in having more similar proportions of
crepuscular and nocturnal species (Fig. 8). The greater proportion of diurnal
species in the A7 horizon reflects a higher proportion of megaherbivores in
comparison to the other horizons.
4.3. Diversity
In raw data the A4 horizon is the most taxon-rich fossiliferous unit, but it
contains the most samples. Price and Webb (in press) used rarefaction analysis
to account for bias related to sample size and demonstrated that A7 is the most
diverse horizon, followed by A4 and A1. Those results are supported here by
Simpson and Shannon-Weiner diversity estimates that indicate that the diversity
of terrestrial taxa decreased dramatically between the time of deposition of A7
and A1 (Fig. 9A-B). Similarly, Pielou and Whittaker indices indicate decreasing
evenness over the same time period (Fig. 9C-D).
Calculations of MacArthur’s dependent and independent models were based
on the number of terrestrial taxa recorded from each horizon (A7: N = 49; A4: N
= 53 taxa; A1: N = 38 taxa). Observed abundances of taxa within each horizon
Table 7. Standard deviations for MacArthur rank abundance models.
Horizon Dependent Independent
A7 0.0608 0.0532
A4 0.0751 0.0676
A1 0.0924 0.0834
were ranked in decreasing abundance and compared to results of the models.
The distribution observed in the fossil assemblages indicate that common taxa
tend to be commoner and rarer taxa tend to be rarer than that predicted by the
dependent model. Thus, the distribution and standard deviations of terrestrial
215
species from each main fossiliferous horizon fit the independent model more
closely than the dependent model (Fig. 10, Table 7).
Fig. 9. Diversity indices of terrestrial taxa from site QML796. A. Simpson’s heterogeneity index;
B. Shannon-Weiner heterogeneity index; C. Pielou’s evenness index; D. Whittaker evenness
index.
4.4. Dating the deposits
Dating results confirm that both QML796 and QML1396 are late Pleistocene
(Table 8). However, the dating results from different materials and methods are
not in agreement with each other and in some cases, are not internally
consistent (Table 8). Generally, AMS dates indicate that deposition occurred in
the late Pleistocene, just prior to the last glacial maximum (Table 8). However,
AMS 14C results for fossil bivalves (Velesunio ambiguus) returned ages that are
problematic. No bivalves from the A7 horizon at site QML796 were submitted for
dating. However, Horizon B of site QML1396 is litho- and biostratigraphically
correlated to the lower portion of A7 and was dated to 44.3 ± 2.2 ka (Price and
Sobbe, 2005). Stratigraphically younger horizons at QML796 returned dates that
fluctuated widely from 33-24 ka within the upper coarse unit of the A4 horizon.
The coarse-grained horizon between A4 and A1 contained associated
216
Fig. 10. MacArthur predicted dependent, independent and actual ranked relative abundance data
of terrestrial taxa from site QML796. A. A7 Horizon; B. A4 Horizon; C. A1 Horizon.
217
Protemnodon sp. remains, and bivalve dates varied between 32-25 ka. Dates
ranged from 33-24 ka in the A1 horizon. Hence, AMS 14C dates from bivalves
provide no resolution for the A4 to A1 sequence and some individual samples
returned dates that are out of stratigraphic order.
Table 8. AMS 14C and U/Th dating results for Darling Downs deposits.
Sample
code
Method Site Material Horizon Age 2 �
error
OZF892 AMS 14C QML796 bivalve A1 28 430 420
OZF893 AMS 14C QML796 bivalve A1 33 690 640
OZF894 AMS 14C QML796 bivalve A1 29 170 460
OZG539 AMS 14C QML796 bivalve A1 24 300 340
OZG540 AMS 14C QML796 bivalve A1 30 280 480
OZF895 AMS 14C QML796 macropod vertebra A1 - -
SS020 AMS 14C QML796 Megalania tooth A1 - -
OZG545 AMS 14C QML796 Protemnodon molar A1 - -
OZG852 AMS 14C QML796 charcoal A1 36 000 1 200
SS051 U/Th QML796 Protemnodon brehus skull A1 55 020 310
OZG541 AMS 14C QML796 bivalve btn A1&A4 25 490 480
OZG542 AMS 14C QML796 bivalve btn A1&A4 32 540 560
OZG853 AMS 14C QML796 charcoal btn A1&A4 40 000 1 500
OZG543 AMS 14C QML796 bivalve A4 33 870 1 260
OZG544 AMS 14C QML796 bivalve A4 24 070 340
OZF899 AMS 14C QML796 macropod rib A4 - -
SS021 AMS 14C QML796 Macropus titan iscisor A4 - -
OZG546 AMS 14C QML796 Protemnodon molar A4 - -
OZG854 AMS 14C QML796 charcoal A4 38 350 1 200
SS056 U/Th QML796 Protemnodon anak skull A4 80 235 399
SS052 U/Th QML796 Protemnodon dentary A7 78 757 514
OZG855 AMS 14C QML1396 charcoal Horizon D 45 150 2 400
OZG548 AMS 14C QML1396 bivalve Horizon B 44 300 2 200
OZG547 AMS 14C QML1396 bivalve Horizon B >49 900 -
SB021 U/Th QML1396 Protemnodon dentary Horizon B 88 350 699
AMS 14C dating of charcoal appears to be more reliable and returned ages in
correct stratigraphic sequence (Table 8). At site QML1396, an overbank unit
218
that overlies the channel deposit was dated to 45.15 ± 2.4 (Price and Sobbe,
2005) and may be similar in age to, or younger than the A7 overbank unit at
QML796. Charcoal recovered from the upper coarse unit of the A4 horizon (site
QML796) was AMS 14C dated to 38.35 ± 1.2 ka. The small coarse fill unit
between A4 and A1 was dated to 40 ± 1.5 ka. Charcoal associated with
megafauna material from the A1 horizon was AMS 14C dated to 36 ± 1.2 ka.
Extraction of collagen from fossil bone and teeth was attempted for dating by
AMS 14C methods, but yield was poor, and the resultant compounds were very
degraded and unlikely to be collagen. Hence, the samples were not suitable for
dating.
Fossil bone dated using U/Th techniques, which provide minimum ages
rather than true ages, returned ages that are significantly older than the AMS 14C dates (Table 8). The dates were not in strict stratigraphic order, but that
could be due to different uranium uptake histories of individual samples.
Megafauna fossil material from the A7 horizon has a U/Th minimum age of
78.75 ± 0.514 ka. U/Th dates obtained for the equivalent stratigraphic unit at
QML1396 return a minimum age of 88.35 ± 0.699 ka. Megafauna material from
the A4 horizon had a minimum U/Th age 80.23 ± 0.399 ka, and from the A1
horizon, a minimum U/Th age of 55.02 ± 0.310 years. Implications of the dates
obtained are discussed below.
5. Discussion
5.1. Palaeoecology
The habitat preferences of taxa in each main fossiliferous horizon of QML796
indicate that a mosaic of habitats was sampled by the creek during the late
Pleistocene. Those habitats included riparian vegetation, vine thickets and
scrubland, open and closed woodlands, and open grasslands (Fig. 11).
MacArthur ranked abundance data of terrestrial taxa support the interpretation
of heterogeneous habitat types (Table 7; Fig. 10).
219
Although the presence in each horizon of several species that have modern
allopatric distributions provide conflicting information regarding palaeohabitat
interpretation, they do provide additional support for a mosaic of habitat types in
the Pleistocene catchment. Non-analogue associations of species are generally
time restricted, being common during the late Pleistocene and rare in the
Holocene (Stafford et al., 1999). Such habitat diversity or patchiness is
commonly hypothesised to have been maintained by more equable climates
with lower seasonality (Lundelius, 1983; 1989). More equable climates may be
achieved via lower temperature and evaporation rates resulting in more
available moisture throughout the year. Such a climatic regime may have
operated on the Darling Downs at times during the late Pleistocene (Price,
2005; Price et al., 2005).
Several other deposits in the Kings Creek catchment contain similar faunas
to those recorded from QML796 (Table 9). The basal fossiliferous unit at site
QML1396 (Horizon B), 200 metres upstream from QML796 (Fig. 1), is
biostratigraphically correlated to the A7 horizon of QML796 (Fig. 2; Price and
Webb, in press). The palaeohabitat at QML1396 is interpreted to have
consisted of a mosaic of habitat types, similar to those of the A7 and A4
horizons at QML796 (Price et al., 2005; Price and Sobbe, 2005). Site QML783
(Fig. 1) is located in a tributary that flows into Kings Creek, and was dated to 47
± 4 ka years using OSL techniques (Roberts et al., 2001). The assemblage is
dominated by large-sized taxa, but Molnar et al. (1999) suggested that that may
reflect sampling bias in the Pleistocene channel system during deposition rather
than subsequent collecting bias. Typical Darling Downs megafauna are
represented in the deposit (Table 9) and indicate the presence of woodlands
and open grasslands during the period of deposition. The large-sized taxa
include Sarcophilus sp., Phascolonous gigas, Thylacoleo carnifex, Diprotodon
sp., Macropus titan and Protemnodon roechus, an assemblage that is generally
characteristic of the A7 horizon of site QML796.
220
Table 9. Terrestrial faunal lists for specific Pleistocene Kings Creek catchment deposits. For
location of deposits, see figure 1.
Species QML100 QML783 QML872 QML913 QML1396
Horizon B
QML1396
Horizon D
Coencharopa sp. x
Gyrococlea sp. x
Austrosuccinea sp. x
Xanthomelon pachystylem x
Strangesta sp. x
Saladelos sp. x
Limnodynastes tasmaniensis x
L.sp. cf. L. dumerili x
Neobatrachus sudelli x
Kyarranus spp. x
Tympanocryptis lineata x x x
“Sphenomorphus Group” x x
Tiliqua rugosa x
Cyclodomorphus sp. x
Megalania prisca x x
Varanus sp. x
Elapid x
Zaglossus sp. x
Sminthopsis sp. x
Dasyurus sp. x x
Sarcophilus sp. x x x
Thylacinus cynocephalus x
Perameles bougainville x
Pe. nasuta x
Phascolomys medius x
Vombatus sp. x x
Phascolonous gigas x x x
Palorchestes sp. x x
Zygomaturus sp. x
Diprotodon sp. x x x x x
Thylacoleo carnifex x x x x
Aepyprymnus sp. x
Sthenurus sp. x x
221
Table 9 continued
Propcoptodon sp. x x x x
Troposodon minor x x x x
Macropus agilis siva x x x x
Ma. titan x x x x x x
Ma. ferragus x
Ma. altus x x
Ma. pearsoni x
Protemnodon anak x x x x x
Pr. brehus x x x x
Pr. roechus x x x
Onychogalea sp. x
Thylogale sp. x
Pseudomys sp. x x
Rattus sp. x x
murid indet x x x
Several other deposits in the catchment, both upstream and downstream
from QML796, contain Pleistocene faunal assemblages (Table 9). However,
stratigraphic relationships of those deposits to site QML796 remain unclear.
Sites QML100, QML872, and QML913 (Fig. 1) all contain faunal elements
whose ecologies broadly suggest open grassland and woodland habitat types.
However, such palaeoenvironmental interpretations are limited because none of
those deposits have been systematically and thoroughly sampled, and smaller-
sized taxa are poorly known owing to the lack of detailed excavations.
Stratigraphic provenance of taxa from those deposits are also poorly known,
hence, the collections may represent time-averaged assemblages. However,
despite such reservations about palaeoenvironmental interpretation, it is clear
that each deposit contains extinct taxa that are characteristic of either the A7 or
A4 horizons of QML796 (e.g., Zaglossus sp., Phascolonous gigas, Palorchestes
sp., Zygomaturus sp., Diprotodon sp., Thylacoleo carnifex, Troposodon minor,
and Protemnodon roechus; Table 9).
222
5.2. Habitat change
Johnson and Prideaux (2004) suggested that Pleistocene megafauna
extinction was not related to climate change or to increased burning (natural or
anthropogenic), because they did not observe differential extinction patterns for
browsers and grazers that might reflect such changes in habitat. Hence, they
preferred an overhunting model for megafauna extinction. However, differential
patterns of extinction for grazers and browsers were observed in the
stratigraphically well-documented QML796 succession (Fig. 6). The differences
in local extinction patterns of Darling Downs browsing and grazing megafauna
could be explained by: 1) taphonomic sampling bias in the Pleistocene
catchment relating to species size; 2) human overhunting of larger-sized
browsing megafauna; or 3) habitat change in the catchment.
Sedimentologic and taphonomic data indicate that each main fossiliferous
horizon had the potential to sample similarly large-sized taxa (Price and Webb,
in press). For example, A1 sampled very large-sized species such as Megalania
prisca (160-650 kg) in abundance, but several equivalent or smaller-sized
browsing taxa such as diprotodontoids and Troposodon minor, common in older
units, are unrepresented in A1. Thus, if those taxa were also present during the
time of deposition of A1, they would be expected to have been sampled during
deposition (Price and Webb, in press). Additionally, rarefaction analysis
demonstrated that differences in diversity between assemblages were not due
to sampling intensity (Price and Webb, in press). Therefore, the differences are
unlikely to reflect selective sampling bias and hypothesis 1 is not supported.
Hypothesis 2 can also be tested using sedimentologic and taphonomic data.
Such data indicate that: a) most bones in each horizon were broken in a dry or
fossilised state; b) cut markings on bones are solely attributable to activities of
non-hominid carnivores; c) megafauna mortality profiles were not biased toward
the vulnerable age classes (i.e., young or senile); and d) accumulation occurred
via natural fluvial processes, rather than via anthropogenic pathways (Price and
Webb, in press). Additionally, there is no record of humans on the Darling
Downs prior to 12 ka (Gill, 1978), and human remains and stone tools are rare
223
in any case and might not be expected to occur in a non-human habitation
accumulation. Collectively, those data do not support a role for human hunting
of Darling Downs megafauna in the late Pleistocene catchment. Therefore,
there is no support for hypothesis 2, although it cannot be rejected.
Fig. 11. Schematic habitat reconstructions of the Pleistocene Kings Creek Catchment. See figure
10 for key to silhouetted megafaunal figures.
The difference between extinction rates of Darling Downs browsers and
grazers is consistent with hypothesis 3, habitat change in the late Pleistocene
catchment. Although each stratigraphic horizon possesses faunal components
of several habitats (i.e., riparian vegetation, vine thickets and scrubland, open
and closed woodlands, and open grasslands), the proportion of habitat types
differed through time (Fig. 11).The ecosystem dynamics of the A7 and A4
horizons were generally very similar to that of modern woodland/mesic habitat
types. However, the habitats appear to have changed through the period of
deposition, so that by the time of deposition of the A1 horizon, the creek
sampled a more open type environment (Fig. 11). It is generally assumed that
browsing taxa are dependent on structurally complex woodlands, while grazers
are associated with more open, grassy habitats (Johnson and Prideaux, 2004).
Hence, the loss of browsing taxa and proportional increase and persistence of
grazing taxa over the time period of deposition probably was related to the
contraction of woodlands and expansion of grasslands. Similarly, a steady
increase in the proportion of fossorial taxa over the time of deposition indicates
an opening up of the environment.
224
Habitat preferences of non-megafaunal taxa that occur within each main
fossiliferous horizon provide additional support for the contraction of closed,
scrubby vine thickets and woodlands as grasslands expanded. Moreover, the
loss of taxa frequenting woodland habitats was not specifically related to large-
bodied species. Several small-sized taxa such as land snails (Paralaoma
caputspinulae), frogs (Kyarranus sp.), bandicoots (Perameles bougainville and I.
obesulus) and murids (Pseudomys gracilicaudatus) that also had specific habitat
requirements for closed, scrubby vine thickets or woodlands, were not
represented in A1, the youngest horizon. The A1 assemblage of small-sized
taxa is largely dominated by species that have specific preferences for open
habitats (Tympanocryptis lineata and Ps. australis) or are taxa with broad
habitat preferences that also occurred in most other fossiliferous horizons
(Austrosuccinea sp., Limnodynastes tasmaniensis, Sphenomorphus Group sp. 1
and 2, Varanus sp. Sminthopsis sp. Perameles nasuta and Rattus sp.). Many of
those small-sized taxa are rare in the assemblages so it may be a case that
they were simply not sampled equally in each unit (e.g., Signor Lipps effect;
Signor and Lipps, 1982). However, it is unlikely that uncommon taxa with broad
habitat tolerances were sampled more readily than were equally uncommon
taxa that had more specific habitat tolerances, and in selected horizons only.
Therefore, the differences in temporal representation of small-sized taxa with
broad versus specific habitat tolerances is more likely related to habitat change,
rather than to sampling bias against rare taxa.
Price and Webb (in press) observed minimally, a two-stage (i.e., gradual)
extinction of Darling Downs megafauna. Their data are not consistent with an
anthopogenically-driven, sudden ‘blitzkrieg’ extinction event, but are consistent
with a climate-forced model of habitat change (Price and Webb, in press), and
the present analysis supports that hypothesis. Thus far, there is no evidence to
suggest that late Pleistocene habitat changes were related to anthropogenic
firing of the landscape. The paucity of charcoal in the sedimentary record
suggests that burning, either anthropogenically or naturally induced, was
insignificant in the late Pleistocene Kings Creek catchment. Other
225
sedimentologic and taphonomic data (e.g., abundant calcrete formation in an
ephemeral fluvial setting, and possible drought-like megafauna mortality
patterns; Price and Webb, in press) from sites QML796 and QML1396 suggest
a seasonally arid climate during the late Pleistocene, therefore, supporting a
role for aridity in driving late Pleistocene Darling Downs habitat change and
geographic range changes (i.e., local extinctions) of taxa.
A comparison of the interpreted late Pleistocene floristics to the modern
floristics of the Kings Creek catchment is limited owing to the extensive amount
of pastoral activity that has occurred since European settlement (Price and
Sobbe, 2005). However, a review of vegetative surveys from the initial period of
settlement indicates that the pre-European catchment was dominated by
grasslands on the floodplain, with grassy or scrubby woodlands confined to the
slopes closer to the Great Dividing Range (Fensham and Fairfax, 1997). Late
Pleistocene scrubland and woodland contraction and grassland expansion in
the catchment may have been a process that continued until the time before
European settlement. Palaeohydrological data from nearby Fraser Island on the
southeastern Queensland coast suggests increasing aridity leading up to a
particularly severe arid interval during the last glacial maximum, and a following
dry interval through the Holocene (Longmore and Heijnis, 1999). Inferred habitat
changes at QML796 were clearly detrimental to the persistence of several
groups and resulted in major decreases in taxonomic diversity and evenness
over time. Generally, the majority of species that are represented both on the
modern Darling Downs and as fossils in the Pleistocene deposits are those
species that have the broadest habitat tolerances. However, very few of the
modern Darling Downs species have a Pleistocene record from the region
(Table 10), suggesting that major faunal turnover occurred between the
deposition of the A1 horizon and the present. The precise timescale of that
faunal turnover remains unclear and appropriately-aged deposits have not been
documented in the catchment.
226
Table 10. Modern Darling Downs mammal species list, excluding recently introduced species. *
indicates a Pleistocene record from QML796; ** indicates genus only or different species
recorded from QML796.
Species
Tachyglossus aculeatus **
Dasyurus maculatus**
Antechinus flavipes **
A. stuartii **
Phascogale tapoatafa
Planigale maculata
P. tenuirostris
Sminthopsis macoura **
S. murina **
Isoodon macrourus **
Perameles nasuta *
Phascolartos cinereus
Petaurus norfolcencis
Petoroides volans
Pe. peregrinus
Trichosurus caninus
Tr. vulpecula
Acrobates pygmaeus
Aepyprymnus rufescens *
Macropus dorsalis **
M. giganteus **
M. parryi **
M. robustus **
M. rufogriesus **
Wallabia bicolor **
Hydromys chrystogaster *
Melomys cervinipes
Notomys mordax
Rattus fuscipes **
R. tunneyi **
227
5.3. Dating and implications
Dating the Darling Downs fossil deposits has proven extremely problematic,
and dates obtained from different materials and methods are difficult to
correlate. However, site QML796 is ideal for evaluating specific suites of dates
because all materials were recovered in sequential stratigraphic order. Hence,
unlike dated collections from isolated sites, the relative ages of dated samples
from QML796 are well constrained. Initial selection of materials for dating
followed criteria intended to reduce the potential for taphonomic bias such as
reworking and stratigraphic leak. Bivalve, charcoal and bone samples used for
dating were unlikely to have been reworked or transported, and individual
bivalves were unlikely to have burrowed into older sedimentary units.
Regardless of the constraints, AMS 14C dates obtained from fossil bivalves
are not invariably in correct stratigraphic sequence within a horizon. Shells in
open systems may be exposed to contamination when carbon is exchanged
with bicarbonate ions in percolating water, resulting in diagenesis and possible
recrystallisation. However, petrographic examination of the fossil bivalves
submitted for dating by AMS methods does not indicate significant
recrystallisation or fungal borings consistent with a major mass balance change
in C content. The microstructure of the fossil bivalves is almost indistinguishable
from that of modern bivalves from the same catchment.
AMS 14C dating results for charcoal samples returned ages in correct
stratigraphic sequence. However, the ages obtained are close to the
chronological limits of the dating technique. As the likelihood of chemical
exchanges with contamination by younger carbon increases with sample age,
the effect of a trace of modern contamination becomes acute as the dating limit
is approached and the quantity of residual 14C is small. Generally, such effects
may make dating less reliable for samples older than 30 000 years (O’Connell
and Allen, 2004).
U/Th dates obtained for fossil material from the Kings Creek deposits are
also problematic. Some dates occur out of stratigraphic order (which is not
unexpected as U/Th dates for fossil bone are only minimum ages), but more
228
importantly, they are approximately 20 000-40 000 years older than dates
obtained on materials using AMS 14C methods. Dates obtained from the
apparently equivalent stratigraphic horizon at two different localities (QML796
and QML1396) differ by ~10 000 years.
Reasons for the discrepancy in ages between samples from the same
stratigraphic horizon (i.e., out of order) and for differences between the two
dating methods invite speculation. The interpretation of U/Th dates for fossil
bones is subject to uranium uptake histories/modes (Pike et al., 2002), which
can be significantly different in different types of fossil materials, e.g., tooth
dentine versus enamel (Zhao et al., 2001). Uranium can also experience
significant mobilisation and leaching (leading to U/Th age overestimation) in
open systems, which may be enhanced in carbonate-rich sedimentary deposits
(Bowler et al., 2003) such as those considered here. All such processes affect
interpretation of U/Th dates. Thus, a combination of U-remobilisation with
variations in the U-uptake histories may explain differences in dates obtained for
different stratigraphic horizons at QML796 and the equivalent stratigraphic
horizon of QML796 and QML1396. Nevertheless, in most circumstances U-
uptake is the dominant process, outweighing U-leaching, simply because bone
apatite is an effective U scavenger (Grün et al., 2000; Pike et al., 2002).
Regardless, in terms of the fossils in this study, it is unknown whether U-
leaching (leading to U/Th age overestimation) occurred. That problem can be
clarified with ICP-MS U concentration profiling across the bones (Pike et al.,
2002) and that study is currently underway.
Regardless of the dating irregularities, the assemblages clearly were
deposited during the late Pleistocene. Whichever dating technique is correct,
deposition of site QML796 occurred over a period of approximately 9 000 - 33
000 years. Importantly, that interpretation does not depend on which technique
is most correct, but on the internal consistency within each technique because
the relative ages of the horizons are firmly established by superposition. Clearly,
significant habitat change and localised species extinctions occurred within the
catchment over that interval of time at QML796. However, in the absence of
229
more reliable dates, it is difficult to determine: 1) the precise temporal scale over
which the habitat change and species extinction occurred; 2) the timing of such
events in relation to the continent-wide extinction of the Australian Pleistocene
megafauna; and 3) the timing of faunal turnover in relation to the human
colonisation of the Sahul (Australia and New Guinea) continent. Regardless of
the problems relating to the dating of Kings Creek fossil deposits, the
interpretations have several important implications for the extinction of the
Darling Downs megafauna.
If those greater ages based on the U/Th dates are accepted, habitat change
and megafaunal extinction occurred on the Darling Downs before 88-55 ka and
any anthropogenic component relating to the extinction may be effectively ruled
out. There is no evidence of human occupancy prior to 12 ka on the Darling
Downs (Gill, 1978), and at most, the age of the A1 horizon may overlap with
initial human colonisation of the Sahul continent. However, data from the A7
and A4 horizons (> 80 ka) indicate that severe habitat change with associated
decreasing faunal diversity, was already well underway, and may pre-date the
arrival of humans in Australia. Ice core and deep sea drilling data from
Antarctica and the southwest Pacific respectively suggest cooler temperatures
between 85-65 ka (Petit et al., 1999; Pahnka et al., 2003). However, warmer
and wetter conditions were present from 65-45 ka (Turney et al., 2001a; Bowler
et al., 2003). That initial cooling may be of geographic significance in the
Southern Hemisphere (Petit et al., 1999) and thus, provide additional support for
the role of climate in driving Pleistocene Darling Downs habitat changes and
species extinctions. Based on the U/Th dates, if early humans did have an
impact on the persistence of Darling Downs megafauna, they were impacting on
an extinction event that was already well underway.
If the AMS 14C dating results of charcoal are more accurate, then
chronologies based on QML796 and QML1396 suggest that deposition took
place from approximately 45-36 ka. Again, there are several important
implications regarding such a hypothesis. Firstly, it implies that some
megafaunal species (Megalania prisca, Macropus titan, Protemnodon anak and
230
P. brehus) survived until at least 36 ± 1.2 ka on the Darling Downs, supporting
recent suggestions that Australian megafauna extinctions occurred after ~ 46.4
ka (e.g., Trueman et al., 2005). Secondly, localised extinction of Darling Downs
megafauna occurred gradually over the period of deposition- there is roughly a
30% stepwise decrease in the number of extinct taxa represented within each
horizon over time (A7: N = 15 taxa; A4: N = 11 taxa; A1: N = 6 taxa). That
suggests that extinction of the megafauna as a whole was not a synchronous
event on the Darling Downs, and therefore, may not have occurred
synchronously across the continent as previously suggested by Roberts et al.
(2001). Thirdly, habitat change and megafauna extinctions took place over a
period of anywhere from ~5 500 to ~12 500 years, potentially overlapping with
the initial human colonisation of the Sahul continent. Proponents of the blitzkrieg
extinction hypothesis suggest that extinction takes place rapidly after human
colonisation (Martin, 1984; Flannery, 1990). Hence, a potentially long duration
between the overlap of Pleistocene megafauna and humans would not support
the ‘blitzkrieg’ extinction hypothesis (Barnosky et al. 2004, Wroe et al., 2004).
Up until 45 ka, the northern monsoon was still operating over much of Australia
(Johnson et al., 1999). However, humidity was decreasing by 40 ka (Turney et
al., 2001a; Bowler et al., 2003), and the continent descended rapidly into a
period of sustained aridity from 40-30 ka resulting in major vegetational changes
in several regions (Kershaw, 1994; Longmore and Heijnis, 1999; Turney et al.
2001b; Field et al., 2002; Bowler et al, 2003). Violent swings in El Niño southern
oscillation from 40 ka (Kershaw et al., 2000) coincided with the intensified aridity
that was sustained from 30 ka to the last glacial maximum (Lambeck and
Chappell, 2001). Such independently derived climatic change chronologies fit
well with late Pleistocene Darling Downs habitat changes and species
extinctions.
However, despite the dating of 25 samples using different methods, an
accurate chronology remains to be established for Darling Downs fossil
deposits. Dating such deposits accurately is critical, and additional dating
techniques must be applied. While it is tempting to favour one suite of dates
231
over the other, considering the disparity between the results of the two methods,
it may yet prove unwise. Clearly, additional dating based on more reliable
materials (e.g., travertines) or more robust assessment of U-uptake leaching
history in the bones is required to test the dates presented here and to
determine the true age of the fauna and chronology of depositional events.
6. Conclusions
A multifaceted palaeoecologic investigation of site QML796, Kings Creek,
Darling Downs, has revealed significant insights into the changing faunas and
habitats of the region during the late Pleistocene. The basal fossiliferous unit
contains a variety of extinct and extant taxa that indicate the presence of a
mosaic of riparian vegetation, vine thickets, scrublands, open and closed
woodlands, and open grassland habitats on the late Pleistocene floodplain. The
geographically small-size of the late Pleistocene catchment precludes the
assemblages being mixtures of material transported from widely distributed
habitats. The woody and scrubby habitats contracted over the period of
deposition, so that by the time of deposition of the youngest horizon, the creek
sampled a more open-type environment. That change potentially continued
through to the time just before European colonisation, when the catchment was
dominated by expansive grasslands, with woodlands confined to hillsides. The
documented habitat changes correlate with the local extinction of several taxa in
the region. The local extinction of megafauna was not body-size specific, as a
variety of large- and small-sized megafaunal taxa were lost over the same
period. Rather, the loss of taxa appears to be selective towards those that
preferred woodlands. Other non-megafaunal taxa that persisted in the youngest
horizon were those that have habitat preferences for open areas, or are
common in a variety of habitats.
AMS 14C and U/Th dating confirm that the Kings Creek deposits are latest
Pleistocene in age, but the dating has proven problematic, and an accurate
chronology is yet to be established. Current dates are equivocal because 14C
dates yielded results that are not in stratigraphic sequence, and 14C and U/Th
232
dates are out of agreement by 20-30 ka or more. Although independent climatic
data better support the charcoal AMS 14C dates to some degree, the older dates
currently cannot be ruled out. Hence, additional efforts to date Darling Downs
sites are critical. Regardless of the dates, however, the data show a strong
correlation of attritional faunal extinction with indicators of climate change from a
single stratigraphic succession. Coupled with sedimentologic data, that
correlation provides support for hypotheses of climate change as the cause for
Darling Downs megafaunal extinction.
Acknowledgments
I thank G. Webb, S. Hocknull, B. Cooke, I. Sobbe, J.-x. Zhao, Y.-x. Feng, B.
Brooke, I. Williamson and A. Cook for helpful discussions on various aspects of
Darling Downs palaeoenvironments. J. Stanisic and A. Baynes assisted in the
identification of molluscs and murids respectively. R. Bell, P. Calquhoun, P.
Hamilton, M. Ng, D. and J. Price, L. Shipton, K.A. Smith, I., D. and A. Sobbe, K.
Spring, T. Sutton, P. Tierney, G. Todd, D. and M. Turner, S. Watt, J. Wilkinson
and countless volunteers provided additional support in the collection and
preparation of fossil material. D. Price prepared figure 11. AMS 14C dating by
ANSTO was supported by AINSE Grants 02/013 and 03/123. U/Th dating by
ACQUIRE was supported by Australian Research Council Linkage Grant
LP0453664. This research was funded in part by both the Queensland
University of Technology and the Queensland Museum.
References
Alroy, J., 2001. A multispecies overkill simulation of the end-Pleistocene
megafaunal mass extinction. Science 292, 1893-1896.
Andrews, P., 1990. Owls, caves and fossils. University of Chicago Press,
Chicago.
Andrews, P., Lord, J.M., Nesbit Evans, E.M., 1979. Patterns of ecological
diversity in fossil and modern mammalian fauns. Biological Journal of the
Linnean Society 11, 177-205.
233
Aplin, K. P., Archer, M., 1987. Recent advances in marsupial systematics with a
new syncretic classification. In: Archer, M. (Ed.) Possums and Opossums:
Studies in Evolution. Surrey, Beatty and Sons and the Royal Zoological
Society of New South Wales, Sydney. xv-1xxii.
Archer, M., 1978. Modern fauna and flora of the Texas Caves area,
southeastern Queensland. Memoirs of the Queensland Museum 19, 111-
119.
Barnosky, A.D., Koch, P.L, Feranec, R.S., Wing, S.L., Shabel, A.B., 2004.
Assessing the causes of late Pleistocene extinctions on the continents.
Science 306, 70-75.
Bartholomai, A., 1973. The genus Protemnodon Owen (Marsupialia;
Macropodidae) in the upper Cainozoic deposits of Queensland. Memoirs of
the Queensland Museum 16, 309-363.
Bartholomai, A., 1975. The genus Macropus Shaw (Marsupialia; Macropodidae)
in the upper Cainozoic deposits of Queensland. Memoirs of the Queensland
Museum 17, 195-235.
Beesley, P.L., Ross, G.J.B., Wells, A., 1998. Mollusca: The Southern Synthesis.
Fauna of Australia. Vol. 5. CSIRO Publishing, Melbourne.
Bowler, J.M., Johnston, H., Olley, J.M., Prescott, J.R., Roberts, R.G.,
Shawcross, W., Spooner, N.A., 2003. New ages for human occupation and
climatic change at Lake Mungo, Australia. Nature 421, 837-840.
Brook, B.W., Bowman, D.M.J.S., 2004. The uncertain blitzkrieg of Pleistocene
megafauna. Journal of Biogeography 31, 517-523.
Buzas, M.A., Hayek, L-a.C., 2005. On richness and eveness within and between
communities. Paleobiology 31, 199-220.
Cogger, H.G., 2000. Reptiles and Amphibians of Australia, 6th Edition. Reed
Books, Australia.
Fensham, R.J., Fairfax, R.J., 1997. The use of the land survey record to
reconstruct pre-European vegetation patterns of the Darling Downs,
Queensland, Australia. Journal of Biogeography 24, 827-836.
234
Fiedel, S., Haynes, G., 2004. A premature burial: comments on Grayson and
Meltzer’s “Requiem for overkill”. Journal of Archaeological Science 31, 121-
131.
Field, J., Dodson, J., 1999. Late Pleistocene megafauna and archaeology from
Cuddie Springs, south-eastern Australia. Proceedings of the Prehistoric
Society 65, 275-301.
Field, J., Dodson, J., Prosser, I., 2002. A late Pleistocene vegetation history
from the Australian semi-arid zone. Quaternary Science Reviews 21, 1023-
1037.
Fifield, L.K., Bird, M.I., Turney, C.S.M., Hausladen, P.A., Santos, G.M., 2001.
Radiocarbon dating of the human occupation of Australia prior to 40 ka BP-
successes and pitfalls. Radiocarbon 43, 1139-1145.
Flannery, T.F., 1990. Pleistocene faunal loss: implications of the aftershock for
Australia’s past and future. Archaeology in Oceania 28, 94-99.
Friend, A.J., 1990. Status of bandicoots in Western Australia. In: Seebeck, J.H.,
Brown, P.R., Wallis, R.L., Kemper, C.M. (Eds.) Bandicoots and Bilbies.
Surrey Beatty & Sons, Chipping Norton, 73-84.
Gill, E.D., 1978. Geology of the late Pleistocene Talgai cranium from S. E.
Queensland, Australia. Archaeology and Physical Anthropology in Oceania
13, 177-197.
Gillespie, R., 2002. Dating the first Australians. Radiocarbon 44, 455-472.
Glasby, C.J., Ross, G.J.B., Beesley, P.L., 1993. Fauna of Australia. Vol. 2A
Amphibia and Reptilia. Australian Government Publishing Service, Canberra.
Grayson, D.K. Meltzer, D.J., 2003. A requiem for North American overkill.
Journal of Archaeological Science 30, 585-593.
Graham, R.W. and Lundelius, E. L. Jr., 1984. Coevolutionary disequilibrium and
Pleistocene extinctions. In: Martin, P.S. & Klein, R.G. (Eds.), Quaternary
Extinctions: A Prehistoric Revolution. University of Arizona Press, Tucson,
pp. 223-249.
Grün R., Spooner, N.A., Thorne, A., Mortimer, G., Simpson, J.J., McCulloch,
M.T., Taylor, L., Curnoe, D., 2000. Age of the Lake Mungo 3 skeleton, reply
235
to Bowler & Magee and to Gillespie & Roberts. Journal of Human Evolution
38, 733-741.
Guthrie, R.D., 1984. Mosaics, allelochemics and nutrients: an ecological theory
of late Pleistocene megafaunal extinctions. In: Martin, P.S. & Klein, R.G.
(Eds.), Quaternary Extinctions: A Prehistoric Revolution. University of
Arizona Press, Tucson, pp. 259-298.
Guthrie, G., 2003. Rapid body size decline in Alaskan Pleistocene horses.
Nature 426, 169-171.
Hecht, M., 1975. The morphology and relationships of the largest known
terrestrial lizard, Megalania prisca Owen, from the Pleistocene of Australia.
Proceedings of the Royal Society of Victoria 87, 239-250.
Horton, D.R., 1984. Red Kangaroos: last of the megafauna. In: Martin, P.S.,
Klein, R.G. (Eds.), Quaternary Extinctions: A Prehistoric Revolution.
University of Arizona Press, Tuscon, pp. 639-680.
Horton, D.R., 2000. The Pure State of Nature. Allen and Unwin, New South
Wales.
Johnson, B.J., Miller, G.H., Fogel, M.L., Magee, J.W., Gagan, M.K., Chivas,
A.R., 1999. 65,000 years of vegetation change in central Australia and the
Australian summer monsoon. Science 284, 1150-1152.
Johnson, C.N., 2005. What can the data on late survival of Australian
megafauna tell us about the cause of their extinction? Quaternary Science
Reviews 24, 2167-2172.
Johnson, C.N., Prideaux, G.J., 2004. Extinctions of herbivorous mammals in the
late Pleistocene of Australia in relation to their feeding ecology: No evidence
for environmental change as cause of extinction. Austral Ecology 29, 553-
557.
Kershaw, A.P., 1994. Pleistocene vegetation of the humid tropics of
northeastern Queensland, Australia. Palaeogeography, Palaeoclimatology,
Palaeoecology 109, 399-412.
Kershaw, P., Quilty, P.G., David, B., Van Huet, S., McMinn., A., 2000.
Palaeobiogeography of the Quaternary of Australia. In Wright, A.J., Young,
236
G.C., Talent, J.A., Laurie, J.R. (Eds.) Palaeobiogeography of Australasian
Faunas and Floras. Memoir of the Association of Australian Palaeontolgists
23, 471-515.
Lambeck, K., Chappel, J., 2001. Sea level change through the last glacial cycle.
Science 292, 679-686.
Lawson, E.M., Elliot, G., Fallon, J., Fink, D., Hotchkis, M.A.C., Hua, Q.,
Jacobsen, G.E., Lee, P., Smith, A.M., Tuniz, C., Zoppi, U., 2000. AMS at
ANTARES- the first 10 years. Nuclear Instruments and Methods in Physics
Research Section B: Beam interactions with Materials and Atoms 172, 95-99.
Longmore, M.E., & Heijnis, H., 1999. Aridity in Australia: Pleistocene records of
palaeohydrological and palaeoecological change from the perched lake
sediments of Fraser Island, Queensland, Australia. Quaternary International
57/58, 35-47.
Lundelius, E.L. Jr., 1983. Climatic implications of late Pleistocene and Holocene
faunal associations in Australia. Alcheringa 7, 125-149.
Lundelius, E.L. Jr., 1989. The implications of disharmonious assemblages for
Pleistocene extinctions. Journal of Archaeological Science 16, 407-417.
MacArthur, R.H., 1957. On the relative abundance of bird species. Proceedings
of the National Academy of Sciences of the United States of America 43,
293-295.
MacArthur, R., 1960. On the relative abundance of species. American Naturalist
94, 25-36.
MacKenzie, N.L., Burbidge, A.A., 1979. The wildlife of some existing and
proposed nature reserves in the Gibson, Little Sandy and Great Victoria
Deserts, Western Australia. Wildlife Research Bulletin of Western Australia 8,
1-36.
Martin, P.S., 1984. Prehistoric overkill: The global model. In Martin, P.S.,Klein,
R.G. (Eds.) Quaternary Extinctions: A Prehistoric Revolution. University of
Arizona Press, Tuscon, 354-403.
McFarland, D. Haseler, M., Venz, M., Reis, T., Ford, G., Hines, B., 1999.
Terrestrial Vertebrate Fauna of the Brigalow Belt South Bioregion:
237
Assessment and Analysis for Conservation Planning. Queensland
Environmental Protection Agency. Brisbane, Queensland.
Meltzer, J.D., Mead, J.I., 1985. Dating late Pleistocene extinctions: theoretical
issues, analytical bias, and substantive results. In: Meltzer, D.J., Mead, J.I.
(Eds.). Environment and Extinction: Man in Late Glacial North America.
University of Maine, Center for the Study of Early Man, Orono, 145-173.
Miller, G.H., Magee, J.W., Johnson, B.J., Fogel, M.L., Spooner, N.A.,
McCulloch, M.T., Ayliffe, L.K., 1999. Pleistocene extinction of Genyornis
newtoni: human impact on Australian megafauna. Science 283, 205-208.
Miller. G.H., Fogel, M.L., Magee, J.W., Gagan, M.K., Clarke, S.J., Johnson,
B.J., 2005. Ecosystem collapse in Pleistocene Australia and a human role in
megafaunal extinction. Science 309, 287-290.
Molnar, R.E., Wilkinson, J.E., Sobbe, I.H., 1999. Pleistocene fauna and
taphonomy at Ned’s Gully, eastern Darling Downs, Queensland. Abstracts of
the 6th CAVEPS, Perth, 7-11 July, 1997. Papers in Vertebrate Palaeontology.
Records of the Western Australian Museum. Supplement 57, 412.
Murray, P.F., 1984. Extinctions downunder: A bestiary of extinct Australian late
Pleistocene monotremes and marsupials. In: Martin, P.S., Klein, R.G. (Eds.),
Quaternary Extinctions: A Prehistoric Revolution. University of Arizona Press,
Tuscon, pp. 600-628.
Murray, P.F., 1991. The Pleistocene megafauna of Australia. In: Vickers-Rich,
P., Monaghan, J.M., Baird, R.F., Rich, T.H., (Eds.), Vertebrate Paleontology
of Australasia. Pioneer Design Studio, pp. 1071-1164.
O’Connell, J.F., Allen, J., 2004. Dating the colonization of Sahul (Pleistocene
Australia-New Guinea): a review of recent research. Journal of
Archaeological Science 31, 835-853.
Pahnka, K., Zahn, R., Elderfield, H., Schulz, M., 2003. 340,000-year centennial-
scale marine record of southern hemisphere climatic oscillation. Science 301,
948-952.
Petit, J.R., Jouzel, J., Raynaud, R., Barkov, N.I., Barnola, J.-M., Basile, I.,
Bender, M., Chappellaz, J., Davis, M., Delaygue, G., Delmotte, M., Kotlyakov,
238
V.M., Legrand, M., Lipenkov, V.Y., Lorius C., Pépin, L., Ritz, C., Saltzman, E.
Stievenard, M., 1999. Climate and atmospheric history of the past 420,000
years from the Vostok ice core, Antarctica. Nature 399, 429-436.
Pike, A.W.G., Hedges, R.E.M., Van Calsteren, P., 2002. U-series dating of bone
using the diffusion-adsorption model. Geochimica et Cosmochimica Acta 66,
4273-4286.
Price, G. J., 2005(2004). Fossil bandicoots (Marsupialia, Peramelidae) and
environmental change during the Pleistocene on the Darling Downs,
southeastern Queensland, Australia. Journal of Systematic Palaeontology 2,
348-356.
Price, G.J., Hocknull, S.A. 2005. A small adult Palorchestes (Marsupialia,
Palorchestidae) from the Pleistocene of the Darling Downs, southeast
Queensland. Memoirs of the Queensland Museum 51, 202.
Price, G.J., Sobbe, I.H., 2005. Pleistocene palaeoecology and environmental
change on the Darling Downs, southeastern Queensland, Australia. Memoirs
of the Queensland Museum 51, 171-201.
Price, G.J., Tyler, M.J., Cooke, B.N., 2005. Pleistocene frogs from the Darling
Downs, southeastern Queensland, Australia, and their palaeoenvironmental
significance. Alcheringa 29, 171-182.
Price, G.J., Webb, G.E., in press. Late Pleistocene sedimentology, taphonomy
and megafauna extinction on the Darling Downs, southeastern Queensland,
Australia. Australian Journal of Earth Sciences.
Prideaux, G.J., 2004. Systematics and Evolution of the Sthenurine Kangaroos.
University of California Publications. University of California Press. London.
England.
Reid, J.R.W., Kerle, J.A., Morton, S.R., 1993. Uluru Fauna: The Distribution and
Abundance of Vertebrate Fauna of Uluru (Ayers Rock-Mount Olga) National
Park. Australian National Parks and Wildlife Service. Canberra.
Roberts, R.G., Flannery, T.F., Ayliffe, L.K., Yoshida, H., Olley, J.M., Prideaux,
G.J., Laslett, G.M., Baynes, A., Smith, M.A., Jones, R., Smith, B.L., 2001.
239
New ages for the last Australian megafauna: continent-wide extinction about
46,000 years ago. Science 292, 1888-1892.
Roberts, R.G., Jones, R., 1994. Luminescence dating of sediments: new light
on the human colonization of Australia. Australian Aboriginal Studies 2, 2-17.
Rose, K.D., 1981. The Clarforkian land-mammal age and mammalian faunal
composition across the Paleocene-Eocene boundary. University of Michigan
Papers on Paleontology 26, v-189.
Shapiro, B., Drummond, A.J., Rambaut, A., Wilson, M.C., Matheus, P.E., Sher,
A.V., Pybus, O.G., Gilbert, M.T.P., Barnes, I., Binladen, J., Willerslev, E.,
Hansen, A.J., Baryshinkov, G.F., Burns, J.A., Davydov, S., Driver, J.C.,
Froese, D.G., Harington, C.R., Keddie, G., Kosintsev, P., Kunz, M.L., Martin,
L.D., Stephenson, R.O., Storer, J., Tedford, R., Zimov, S., Cooper, A., 2004.
Rise and fall of the Beringian steppe bison. Science 306, 1561-1565.
Signor, P. W., III, & Lipps, J. H., 1982. Sampling bias, gradual extinction
patterns and catastrophes in the fossil record. Geological Society of
America Special Papers 190, 291-296.
Simpson, J.J., Grün, R., 1998. Non-destructive gamma spectrometric U-series
dating. Quaternary Geochronology 19, 1009-1022.
Stafford, T. W. Jr., Semken, H. A. Jr., Graham, R. W., Klippel, W. F., Markova,
A., Smirnov, N. G. Southon, J., 1999. First accelerator mass spectrometry
14C dates documenting contemporaneity of non-analog species in late
Pleistocene mammal communities. Geology 27, 903–906.
Strahan, R., 1995. The Mammals of Australia. Reed Books. Sydney.
Thorne, A., Grün, R., Mortimer, G., Spooner, N.A., Simpson, J.J., McCulloch,
M., Taylor, L., Curnoe, D., 1999. Australia’s oldest human remains: age of the
Lake Mungo 3 skeleton. Journal of Human Evolution 36, 591-612.
Trueman, C.N.G., Field, J.H., Dortch, J., Charles, B., Wroe, S., 2005. Prolonged
coexistence of humans and megafauna in Pleistocene Australia. Proceedings
of the National Academy of Sciences 102, 8381-8385.
Turney, C.S.M. Bird, M.I., Roberts R.G. 2001a. Elemental �13C at Allen’s Cave,
Nullarbor Plain, Australia: assessing post-depositional disturbance and
240
reconstructing past environments. Journal of Quaternary Science 16, 779-
784.
Turney, C.S.M., Kershaw, A.P., Moss, P., Bird, M.I., Fifield, L.K., Cresswell,
R.G., Santos, G.M., Di Tada, M.L., Hausladen, P.A., Zhou, Y., 2001b.
Redating the onset of burning at Lynch’s Crater (North Queensland):
implications for human settlement in Australia. Journal of Quaternary Science
16, 767-771.
Van Dyck, S.M., Longmore, N.W., 1991. The mammals records. In: Ingram
G.J., Raven R.J. (Eds.), An Atlas of Queensland’s frogs, reptiles, birds and
mammals. Board of Trustees of the Queensland Museum, Queensland, pp.
284-336.
Vermeij, G.J., Leighton, L.R., 2003. Does global diversity mean anything?
Paleobiology 29, 3-7.
Walker, K.F., 1981. Ecology of Freshwater Mussels in the River Murray.
Australian Water Resources Council Technical Paper. Australian
Government Publishing Service. Canberra.
Wang, X., van der Kaars, S., Kershaw, A.P., Bird, M., Jansen, F., 1998. A
record of fire, vegetation and climate through the last three glacial cycles
from Lombok Ridge core G6-4, eastern Indian Ocean, Indonesia.
Palaeogeography, Palaeoclimatology, Palaeoecology 147, 241-256.
Williams, S.E., Pearson, R.G., Walsh, P.J., 1996. Distributions and biodiversity
of the terrestrial vertebrates of Australia’s Wet Tropics: a review of current
knowledge. Pacific Conservation Biology 2, 327-362.
Willig, M.R., 2003. Challenges to understanding dynamics of biodiversity in time
and space. Paleobiology 29, 30-33.
Woirnarski, J.C.Z., 1992. A Survey of the Wildlife and Vegetation of Purnululu
(Bungle Bungle) National Park and Adjacent Area. Research Bulletin 6.
Department of Conservation and Land Management. Como, Western
Australia.
Wroe, S., 2002. A review of terrestrial mammalian and reptilian carnivore
ecology in Australian fossil faunas, and factors influencing their diversity: the
241
myth of reptilian domination and its broader ramifications. Australian Journal
of Zoology 50, 1-24.
Wroe, S., Crowther, M., Dortch, J. & Chong, J., 2003a. The size of the largest
marsupial and why it matters. Proceedings of the Royal Society of London B
series 271, 34-36.
Wroe, S., Field, J., Fullager, R., Jermiin, L.S., 2004. Megafaunal extinction in
the late Quaternary and the global overkill hypothesis. Alcheringa 28, 291-
331.
Wroe, S., Myers, T., Seebacher, F., Kear, B., Gillespie, A., Crowther, M. &
Salisbury, S., 2003b. An alternative method for predicting body mass: the
case of the Pleistocene marsupial lion. Paleobiology 29, 403-411.
Zhao, J.-x., Xia, Q., Collerson, K.D., 2001. Timing and duration of the last
interglacial inferred from high resolution U-series chronology of stalagmite
growth in Southern Hemisphere. Earth and Planetary Science Letters 184,
635-644.
242
GENERAL DISCUSSION
SIGNIFICANCE OF STUDY
This research substantially builds on previous work on Australian, and
particularly Darling Downs, Pleistocene fossil deposits on several different
levels. The Kings Creek catchment provides a unique opportunity to examine
detailed palaeoecological aspects of a Pleistocene floodplain community in a
small geographic sampling area. Fossil accumulations within floodplain
deposits are typically transported, and it is commonly difficult, or in some
cases impossible, to reliably constrain the sampling area of palaeodrainages.
In this study, regional topography was used to constrain the sampling area of
the Pleistocene channel using the size of the modern catchment as an
analogy. The Pleistocene channel was relatively small, hence, fossil material
could not have been transported over distances greater than 25-30 km.
Thus, palaeoecological implications represent a small, well-constrained
geographic area.
Systematic collecting methods utilised during this project were designed to
target the recovery of both large and small-sized taxa. Such methods are
rarely employed in palaeontology owing to their labor intensive nature.
Hence, this project recovered considerable amounts of data that generally
are not available. The methods utilised were particularly important to balance
previous collecting methods that tended to favour large-sized forms and
specimens. The methods led to the recovery of a new species of bandicoot
(Perameles sobbei Price) and several other taxa previously unknown as
fossils on the Darling Downs, including: Glyptophysa gibbosa, Gyraulus
gilberti, Paralaoma caputspinulae, Coencharopa sp., Gyrococlea sp. 1 and 2,
Austrosuccinea sp., Xanthomelon pacystylum, Strangesta sp., Saladelos sp.
(pulmonate molluscs); Limnodynastes tasmaniensis, L. sp. cf. L. dumerili, L.
sp. cf. L. spenceri, ?Limnodynastes sp., Neobatrachus sudelli, Kyarranus sp.
1 & 2 (frogs); Tympanocryptis lineata, “Sphenomorphus Group” 1, 2 and 3,
Tiliqua rugosa, Cyclodomorphus sp. (dragon lizards and skinks);
Tachyglossus sp., Zaglossus sp. (echidnas); Sminthopsis sp., Antechinus sp.
(dasyurids); Isoodon obesulus, Perameles bougainville, Pe. nasuta
243
(bandicoots); Bettongia sp. (bettong); Pseudomys gracilicaudatus, Ps.
australis and Hydromys chrystogaster (rodents). The results support Molnar
and Kurz’s (1997) hypothesis that small-sized taxa were more diverse and
widespread during the late Pleistocene than previously considered.
Pleistocene geographic range extensions have also been revealed for
several of those taxa. Additionally, unique, non-analogue assemblages of
species previously unknown to have occurred sympatrically were also
revealed in the Darling Downs fossil record (e.g., bandicoots- Isoodon
obesulus, Perameles bougainville & Pe. nasuta).
The newly documented assemblages have increased the precision of
previous palaeoenvironental interpretations of the region significantly.
Additionally, palaeoecologic analyses followed methodology rarely utilised in
Australian palaeontology. Investigations of specific species ecologies,
coupled with analogies to modern communities and diversity estimates,
allowed for high resolution interpretations of Pleistocene habitats. Several
previously unrecognised habitats were revealed from the assemblages of the
deposits including vine thickets, riparian habitats and closed woodlands.
More precise details of the structure of certain previously recognised habitat
types (e.g., open sclerophyllus woodlands with sparse, scrubby or grassy
understories) were also revealed. Climatic variables could also be inferred
from the analysis of groups such as frogs and bandicoots. For example,
some assemblages of bandicoots from the deposits represent non-analog
assemblages, thereby suggesting more equable seasonality (possibly
maintained by lower temperatures and lower evaporation rates; cf.,
Lundelius, 1983) during the late Pleistocene. That hypothesis is supported
by assemblages of frogs in the deposits. The consistently small body-size of
populations of fossil frogs may have been maintained in an environment that
experienced more equable climates that of today.
Detailed documentation of stratigraphic and sedimentologic aspects of
fossil deposits allowed interpretation of depositional environments.
Depositional systems in the catchment included channel and overbank type
deposits. Such deposits have variable taphonomic signatures, and those that
were identified were critical for identifying certain types of bias in the fossil
record. Sedimentological data also revealed information regarding
244
palaeocurrent directions and allowed differences between stratigraphic units
to be qualitatively assessed. Documentation of stratigraphic horizons of
Kings Creek deposits allowed litho- and biostratigraphic correlations to be
made between sites QML796 and QML1396. Additionally, sedimentary
structures and taphonomic signatures indicated seasonally arid conditions in
the late Pleistocene catchment.
Taphonomic analyses also helped discriminate the provenance of
vertebrate and non-vertebrate material prior to deposition and constrained
the sampling area of the Kings Creek catchment. Taphonomic analyses
allowed for the documentation of the degree of autochthonous and
allochthonous components of the assemblages. Many unidentifiable bone
shards and ‘bone pebbles’ are variably abraded and experienced varying
degrees of transport and possibly multiple cycles of reworking. However,
identifiable bones analysed for palaeoenvironmental analyses suggest that
that material was derived proximal to the final point of deposition, and that
fluvial transport was minimal. Such an interpretation is consistent with the
small Pleistocene catchment size. Taphonomic analyses also revealed
several biases that may be related to the differential preservation of different
vertebrate groups. Several of those biases have not previously been
documented (e.g., preservation of agamids versus scincids), and hence, the
taphonomic significance of such bias is unclear. Taphonomic analyses
allowed for the meaningful comparisons of assemblages between
stratigraphic horizons at varying temporal and spatial scales.
The combined investigation of stratigraphic, sedimentologic, taphonomic
and palaeoecologic aspects of the deposits allowed for high resolution
documentation of late Pleistocene habitats and interpretation of
environmental change. Of critical importance is the occurrence of several
superposed assemblages at localities QML796 and QML1396, with
stratigraphically definable sequences that allowed recognition and
interpretation of temporal changes in the local faunas. Unfortunately, at site
QML1396, it could not be determined if the rarity of megafauna in the upper
horizon was due to local extinction or to a bias in accumulation due to
differential sorting during deposition of the overbank deposits. However, at
site QML796, decreasing diversity was shown not to reflect sample or
245
taphonomic bias. At QML796, the creek appears to have sampled a
progressively more open-type environment from older to younger
assemblages. Such changes were detrimental to the persistence of several
taxa in the region and resulted in decreasing faunal diversity over the period
of deposition. Significantly, the temporal decrease in megafaunal diversity
was a gradual process. Faunal changes were likely related to species habitat
preferences rather than other factors, such as body size. Taxa recorded in
the youngest stratigraphic units were those that have habitat preferences for
open areas, or are common in a variety of habitats. Additionally, several taxa
recorded in the Darling Downs fossil record that are extant in the region
today are those taxa that have non-specific habitat requirements (e.g.,
Limnodynastes tasmaniensis, Tachyglossus sp., and Perameles nasuta).
There is no evidence for human-megafauna interaction on the Darling
Downs during the late Pleistocene, and the post parsimonious hypothesis is
that habitat changes and species extinctions were climatically driven.
Dating analyses indicate that the deposits are late Pleistocene in age.
However, the results from different dating methods are not in agreement with
each other. Determining an accurate chronology of deposition is one of the
most important aspects of the entire study, but has proven to be problematic.
Regardless, the dating results have very important implications regarding
megafaunal extinction.
MEGAFAUNA EXTINCTION HYPOTHESES
Based on the preceding comprehensive analyses that combined dating,
lithofacies, depositional environment, taphonomic, and palaeoecologic
analyses, it is possible to directly compare the results of this study to the
numerous existing hypothetical megafaunal extinction models.
Anthropogenic models
Blitzkrieg / Overkill
Most overkill hypotheses suggest that megafauna extinctions took place
rapidly (blitzkrieg <500 years; generalised overkill ~1,500 years) following
initial human colonisation (Whittington & Dyke, 1984; Barnosky et al.,
246
2004b). U/Th and radiocarbon dating of Darling Downs megafauna deposits
suggest that deposition occurred either 88-55 ka or 45-36 ka respectively.
Stratigraphic and taphonomic data indicate minimally, a two-stage (i.e.,
progressive) extinction of Darling Downs megafauna (with some megafaunal
taxa still present in the youngest units). Collectively, those data suggest that
an attritional, rather than catastrophic, extinction event occurred in the late
Pleistocene Darling Downs over an extended period of time (i.e, 9-33 ka).
Although the timing of human arrival in Australia remains controversial
(O’Connell & Allen, 2004), the long time intervals of deposition established in
this study, although currently imprecise, unequivocally rule out blitzkrieg and
generalised overkill extinction for the majority of late Pleistocene Darling
Downs megafauna.
Prideaux (2004) proposed an attritional overkill extinction hypothesis
where increasing human hunting pressure over periods of ~20 000 years
eventually led to megafauna extinction. Although Darling Downs megafauna
extinctions were attritional, there is no direct evidence supporting the role of
humans in the extinction. The taphonomic component of the study
conclusively demonstrated that the accumulations were not via
anthropogenic pathways. The accumulations are typically fluvial in origin and
cut marks on bone are related to predation or scavenging by non-hominid
species (predominantly Thylacoleo carnifex). Additionally, there were no
anthropogenic cultural artefacts recovered from any of the deposits
investigated. Based on the current evidence, and allowing for the findings
from archaeological sites in the study area (e.g., Gill, 1978), the megafauna
deposits pre-date the first record of humans in the region by at least 30-35
thousand years.
Sitzkrieg
Sitzkrieg extinction hypotheses suggest that indirect anthropogenic-related
factors such as the introduction of predators/competitors and land
management techniques (e.g., fire use) eventually led to: 1) increased
competition between native species; 2) increased predation on native
species; and 3) loss of preferred habitats of endemic faunas (Diamond,
1989b; Barnosky et al., 2004b). Such changes had the potential to cause
247
faunal extinctions (Worthy & Holdaway, 2002). However, It is unknown
whether Pleistocene humans directly or indirectly introduced non-endemic
taxa into Australia. Hence, anthropogenically introduced predator/competitor
hypotheses cannot be tested here.
Although controversial, indirect, late Pleistocene anthropogenic land
management practices, such as burning, have been suggested for some
areas of Australia (Bowman, 1998; 2002; Wang et al., 1998; Luly, 2001;
Turney et al., 2001). However, the paucity of charcoal in the Pleistocene
Darling Downs fossil record does not support burning as a significant factor
in the palaeoenvironment. Some modern taxa that occurred in the
Pleistocene Darling Downs have extant populations that prefer vegetative
mosaics that are maintained by periodic burning (e.g., Isoodon obesulus).
However, it appears that fire may not have necessarily played a significant
role in maintaining Pleistocene Darling Downs vegetative mosaics.
Alternatively, Pleistocene Darling Downs vegetative mosaics may have been
maintained by feeding habits of megaherbivores such as Diprotodon sp. and
Zygomaturus sp. (cf., Owen-Smith, 1987; 1988; Zimov et al., 1995), and/or
equable climates (cf., Lundelius 1983; 1989).
Hyperdisease
The hyperdisease extinction hypothesis suggests that megafauna were
susceptible to virulent diseases introduced by initial human colonisers, either
directly or with species that accompanied them (MacPhee & Marx, 1997;
Fiedel, 2005). Large-sized taxa may be more susceptible to disease than
small-sized taxa (MacPhee & Marx, 1997; Fiedel, 2005). However, the local
extinctions of Pleistocene Darling Downs taxa do not appear to have been
specifically related to body-size, nor to specific taxonomic groupings. Rather,
species habitat preferences appear to have been the major factor influencing
the disappearance of taxa in the fossil record. Therefore, the hyperdisease
hypothesis is not supported for the extinction of Pleistocene Darling Downs
megafauna.
248
Climate models of extinction
Co-evolutionary disequilibrium model
Coevolution refers to the evolution of multiple taxa that share close
ecological relationships and develop close interactions during times of
environmental stability (Graham & Lundelius, 1984). Perturbations such as
climate change can disrupt coevolved communities and result in
individualistic responses in species, causing ecosystems to significantly
restructure (Barnosky, 2001). The coevolutionary disequilibrium model
suggests that late Pleistocene climatically-driven ecosystem changes: 1)
disrupted the equilibrium of coevolved communities, 2) reduced niche
differentiation; 3) increased species competition; and 4) eventually led to
species extinction (Graham & Lundelius, 1984). Individualistic responses of
species were not restricted to particular taxonomic groupings, body-size or
ecological categories. A major difficulty in postulating the effects of such
climatic change and its effects on Pleistocene communities is the general
lack of knowledge of the interaction of species in the past.
Several extant taxa that are allopatric today occurred sympatrically in the
Pleistocene Darling Downs. Such ‘non-analogue’ assemblages of extant taxa
suggest that the Pleistocene Darling Downs may have had a more equable
climate than occurs today and a greater range of habitat niches to support
such populations. For example, assemblages of Isoodon obesulus,
Perameles bougainville and Pe. nasuta are allopatric today, but were
recorded in a single, discrete stratigraphic horizon at QML796. Extant
populations of I. obesulus occur throughout southern Australia and far north
Queensland; Pe. bougainville, occurred throughout southern central
Australia in historic times, but is presently restricted to islands of the Western
Australia coast; and Pe. nasuta is extant on the Darling Downs and the
eastern margin of Australia. That suggests that since the late Pleistocene,
each of those species moved independently of each other. Although such a
conclusion in based on end points only (there is little information available
regarding species distributions between the Pleistocene and initial European
colonisation), bandicoot distributions are consistent with the hypothesis that
species in the past, responded individualistically to environmental changes.
249
The Darling Downs fossil record demonstrates that there was only a
minimal trend for taxonomic groups to adjust their geographic range (i.e.,
undergo local extinction) over the period of deposition (e.g., diprotodontoids).
Demonstrating the extinction of most taxonomic groups in the fossil record is
difficult due to low numbers of individuals and their apparent absence could
result from their initial rarity (e.g., Signor & Lipps, 1982). However, the
temporal loss of late Pleistocene taxa Darling Downs taxa is not correlated to
body size. Hence, data from the Darling Downs fossil record is consistent
with the co-evolutionary disequilibrium model of species extinction.
Mosaic-nutrient model
The mosaic-nutrient extinction model suggests that late Pleistocene climatic
changes disrupted seasonal regimes, decreased plant diversity and
increased zonation (Guthrie, 1984). That led to increasingly homogeneous
habitats and was detrimental to the persistence of mammal communities
resulting in: 1) less community diversity; 2) range contractions; 3) lowering of
body mass; and eventually 4) species extinction (Guthrie, 1984).
Pleistocene Darling Downs seasonal regimes were likely to have been
more equable than at present. The modern Darling Downs is highly seasonal
and experiences significant summer rainfall (Australian Bureau of
Meteorology). Although sedimentological data suggests that the late
Pleistocene Darling Downs climate was seasonal during the interval of
deposition, it is likely that seasonality increased markedly during the
approach of the last glacial maximum (Longmore & Heijnis, 1999; Hope et
al., 2004). Within the Darling Downs fossil record, it is evident that
Pleistocene habitats were becoming increasingly homogeneous over the
period of deposition, leading to decreased faunal diversity. Local extinctions
of several taxa were recorded in the deposit. However, geographic range
contractions of particular species are difficult to track using currently
available data, although several taxa clearly adjusted their ranges between
the late Pleistocene and present (e.g., Kyarranus sp., Ornithorhynchus
anatinus, Pseudomys gracilicaudatus). There was no obvious trend towards
decreasing body size of individual taxa, and that remains a difficult
hypothesis to test with high levels of statistical confidence considering
250
relatively small sample sizes. Generally, there is some support for the
mosaic-nutrient extinction model for late Pleistocene Darling Downs
extinctions.
Multicausal or ecological models of extinction
Multicausal megafauna extinction models suggest that a combination of
climate changes and human interactions culminated in megafaunal extinction
(Calaby, 1976, Murray, 1991; Field & Dodson, 1999; Barnosky et al., 2004b;
Wroe, 2005; Boeskorov, 2006). Such hypotheses are difficult to test in the
absence of reliable chronologies of deposition. Current U-series and
radiocarbon chronologies suggest that the late Pleistocene Darling Downs
extinction phase took place between either 88-55 ka or 45-36 ka
respectively. If the growing consensus that humans arrived in Australia after
50 ka is correct (Fifield et al., 2001, Gillespie, 2002; O’Connell & Allen,
2004), the older U-series dates unequivocally suggest that the habitat
changes and species local extinctions occurred prior to human arrival in
Australia. If the earliest Australian humans did have an impact on the
extinction of the Darling Downs megafauna, they were simply compounding
on an extinction event all ready well underway. The younger AMS 14C dates
suggest that the late Pleistocene Darling Downs habitat changes and
species extinctions occurred after humans arrived in Australia. Correlation of
independent climatic data with the radiocarbon chronologies support the
timing of the interpreted habitat changes 45-36 ka. However, stratigraphic,
sedimentologic, taphonomic and palaeoecologic data suggest that such
changes may have occurred irrespective of potential human involvement.
Keystone herbivore model
Keystone species are megaherbivores that are immune to non-human
predation effects, and hence, can maintain large population sizes that can
radically affect vegetation structure (Owen-Smith, 1987; 1988; Sinclair,
2003). Removal of keystone species via naturally-driven climatic factors or
hunting can promote irreversible changes to plant communities (Owen-
Smith, 1987, 1988; Zimov et al., 1995). The keystone herbivore extinction
hypothesis relies on the fact that the first megafauna that disappear are
251
keystone species. Within the late Pleistocene Darling Downs, the two largest
megaherbivores, Diprotodon sp. and Zygomaturus sp., appear to have gone
extinct at slightly different rates, but were among the first taxa to disappear in
the fossil record. Although several smaller-sized taxa, likely dependent on
broadly similar habitat types, went extinct at similar rates, the hypothesis
cannot be rejected. However, as discussed above, there is no evidence to
support an anthropogenic component in the extinction of Pleistocene Darling
Downs megaherbivores.
Self-organised instability
The self-organised instability (SOI) hypothesis suggests that a combination
of increased post-Pliocene aridity, increased speciation, and immigration of
fauna from southeast Asia during the Pleistocene led to community instability
(Forster, 2003). Increases in the immigration of humans in the late
Pleistocene may also have increased the connectivity of other faunal
elements into Australia causing significant disruption to prevailing
communities and eventually resulted in species extinction (Forster, 2003).
Again, the SOI hypothesis is difficult to test using current imprecise
chronologies of late Pleistocene Darling Downs habitat changes and species
extinctions. To properly test the SOI hypothesis on the Darling Downs and
other regions, more reliably dated assemblages are needed from varying
spatial and temporal scales.
FUTURE DIRECTIONS
In general, more rigorous dating analyses are necessary to test the results
presented here from the Darling Downs. Additional work is required on the
analysis of the microstructure of the bivalves that were submitted for dating.
That may provide evidence for why the 14C dating results were so variable.
Additionally, portions of those individual bivalves that were dated using
AMS14C were also submitted for amino acid racemisation (AAR; C. Murray-
Wallace, University of Wollongong) and U/Th (Jian-xin Zhao, AQUIRE,
University of Queensland) analysis to test the validity of the AMS 14C results
252
using independent methods. Unfortunately, the results of those analyses are
not yet available.
In addition to mollusc shells submitted for U/Th dating, calcrete samples
have already been submitted for dating using U/Th methods. However, the
calcretes have extremely high levels of detritus, and in combination with the
open-system behaviour of the calcrete, meaningful ages could not be
calculated (Zhao, pers. comm, March 2005). Detailed analysis of the
mineralogy of calcrete is required to assess its potential for dating in the
deposit. Calcretes may be suitable for U/Th dating only if: 1) micrite and/or
spar are the dominant components; 2) cathodoluminescense for those
phases are weak; 3) Fe and Al levels are low; and 4) Sr levels are close to
the average of the studied deposit (Mallick & Frank, 2002). Such was not the
case for the submitted samples.
A possibility for assessment of the bone U/Th dates is to use the Pike
(2002) method of ICP-MS profiling of U concentrations across the bone. That
method assesses the uptake history of U and can determine whether U
leaching occurred, or whether U was taken up early or late during the burial
history. Thus, a diffusion-adsorption model of U-uptake may be applied to
calculate U-series dates with improved reliability (Millard & Hedges, 1996;
Pike et al., 2002).
Material has also been collected for other independent dating methods in
order to test the AMS 14C and U/Th results. Sediment samples were
collected prior to the commencement of this study for OSL dating and were
submitted to R.G. Roberts, University of Wollongong. However, the samples
have not been processed and results are unavailable. Samples have also
been collected that may be suitable for dating using electron-spin resonance
(ESR) dating methods, but have not yet been submitted.
Overall, the detailed stratigraphic, sedimentologic, taphonomic,
palaeoecologic and dating analyses of Kings Creek catchment deposits
provide a foundation for future work on similar aspects of fossil deposits from
the entire region. However, several of the hypotheses presented in this study
can be tested in the absence of reliable dates. For example, more
independent site studies from more widely-spaced geographic areas, in
combination with palaeocatchment analyses, are required to test hypotheses
253
about the proximity of certain habitats to specific sites of fossil accumulation.
Also, previous hypotheses that suggested that the Darling Downs represents
only a single local fauna (i.e., Molnar & Kurz, 1997) can be assessed only
with detailed investigations of additional fossil deposits.
Future systematic collecting of fossil deposits should target the recovery of
both large and small-sized species in order to allow meaningful comparisons
to the results presented here. Such collecting must also involve the thorough
stratigraphic documentation of the fossil deposit so temporal changes in
communities can be documented at each locality. More detailed
stratigraphical and sedimentological work is also required both in the Kings
Creek catchment and other Darling Downs deposits to examine stratigraphic
relationships at more regional scales. Determination of taphonomic modes of
accumulation are required to assess the relative degree of bias between
fossil assemblages. Rarefaction and other statistical analyses on taxon
abundance data are useful for testing the potential of bias introduced by
differences in sample size. Additionally, comparative taphonomic
experiments are required to help elucidate factors relating to the differential
preservation of mammals versus non-mammals (e.g., squamates), and
within non-mammal groups (e.g., agamids versus scincids), in order to
explain patterns observed in the fossil record. Collectively, those methods
will assist in the meaningful comparison between different stratigraphic
horizons and reveal biases that may affect palaeoecological interpretations.
Most prevailing megafauna extinction hypotheses were developed on
continental and global scales. However, it is imperative to test such
hypotheses on local and regional scales, such as are represented by the
Darling Downs. Although current evidence does not provide unambiguous
support for any of the prevailing climate-driven megafauna extinction
hypotheses, there is currently no evidence implicating a role for humans in
Darling Downs megafaunal extinctions. Although it may be over-simplistic to
simply suggest that climate change drove Darling Downs megafaunal
extinction, new results obtained here are consistent with that hypothesis.
Additionally, this research highlights the need to expand the project over
wider temporal and spatial scales, thus allowing more specific testing of
human versus climate hypotheses and more precise determination of the
254
operational details and mechanisms driving megafaunal extinction. It may be
the case that humans played a more significant role elsewhere, but there is
currently a paucity of data linking megafauna and human interactions.
Recent studies from other regions (e.g., Cuddie Springs) are beginning to
demonstrate that megafaunal extinctions occurred gradually against a
backdrop of climatic deterioration; any role of humans remains
undocumented (Trueman et al., 2005).
Another significant value of the Darling Downs fossil record is that a high
proportion of the identified taxa are extant. Such taxa may not necessarily
occur on the Darling Downs today, but they do occur in other areas of
Australia and New Guinea. That suggests that extant species have
undergone significant range adjustments between the Pleistocene and
present. Knowledge of how species responded to climatic changes in the
past is essential for the development of future conservation strategies
(Barnosky et al 2004a). However, there is currently a paucity of data
regarding Pleistocene distributions of extant Australian taxa. That is primarily
due to a lack of well documented deposits that have incorporated detailed
aspects of stratigraphy, taphonomy and dating. Future research should aim
to document the spatial and temporal extent of both extant and extinct
faunas from the entire continent, and that will lend support to the
development of detailed conservation strategies and highlight the potential
risks faced by specific extant species.
SUMMARY
Few significant Australian late Pleistocene megafauna sites have been
examined as thoroughly as some of those deposits presented in this study.
The attributes of the present study that stand out from most previous
investigations include: 1) the sites represent a crucial time interval, i.e., they
bracket some megafaunal local extinction; 2) the deposits were excavated in
such a way that multiple separate accumulations were recovered that
represent a known stratigraphic, and hence, temporal sequence; 3) the
excavation technique also allowed detailed sedimentologic studies with
informed taphonomic analyses; and 4) both large and small-sized taxa were
255
recorded through the processing of many cubic metres of sediment. The
strength of the palaeoecologic interpretations lie in their testability and the
congruence between stratigraphy, sedimentology, taphonomy. Results and
interpretations presented in this study highlight the significance of the fossil
deposits of the Darling Downs and their value for understanding late
Pleistocene species extinction and habitat change.
256
CONCLUSIONS
1) Regional topography of the modern Kings Creek catchment serves as an
analogue for estimating the catchment size during the late Pleistocene
because it is bordered largely by regional and continental divides. The late
Pleistocene Kings Creek catchment was geographically small and faunal
elements could not have been transported into the deposits from distances
greater than 25-30 km. Hence, all recovered fossils were sourced from local
environments.
2) More than 70 taxa were identified in the deposits, including 35 taxa that
were previously unknown to have occurred in the Darling Downs fossil
record. In particular, many small-sized species including land snails, frogs,
skinks, agamids, dasyurids, bandicoots and rodents were identified in the
Darling Downs for the first time. Additionally, one new species (Perameles
sobbei Price) was formally identified and five other potentially new taxa were
left in open nomenclature (?Limnodynastes sp.; Kyarranus sp. 1 & 2;
Dasyurus sp.; Palorchestes sp.).
3) Fossil accumulation processes are dominated by high-energy channel
deposition and lower energy, episodic overbank deposition. An extensive
basal fossiliferous horizon representing a major channel at QML796 and
QML1396 is litho- and biostratigraphically correlated.
4) Fossil preservation ranges from articulated skeletons to disarticulated and
highly fragmented abraded remains. Accumulations were made by fluvial
processes and cut marks on bones were related to feeding by non-hominid
carnivores. Several biases were identified relating to the differential
preservation of different skeletal elements and/or taxa. Assemblages are
dominated by small-sized taxa (i.e. <5 kg).
5) Palaeoclimate estimates based on small-sized taxa that occur in the
deposits indicate that the late Pleistocene Darling Downs climate was more
equable than present. Sedimentologic and taphonomic data suggest a
257
seasonally arid climate (e.g., abundant calcrete formation in an ephemeral
fluvial setting, and drought-like macropod mortality patterns).
6) Late Pleistocene Kings Creek catchment habitats included riparian
vegetation, vine thickets, scrubland, closed and open grassy woodlands, and
open grasslands. The late Pleistocene creek sampled an increasingly
homogeneous environment over the period of deposition. That reflected the
contraction of woodlands, scrublands and vine thickets, and expansion of
grasslands on the floodplain.
7) Several megafaunal taxa (e.g., Diprotodon sp., Troposodon minor,
Macropus agilis siva) suffered local extinctions over the period of deposition.
Other megafaunal taxa (e.g., Megalania prisca, Macropus titan, Protemndon
anak, P. brehus) persisted in the youngest units. Hence, those data suggest
minimally, a two-stage extinction of Darling Downs megafauna. Such
extinctions were not body-size specific, but rather, reflected species habitat
preferences.
8) U-series and radiocarbon dating indicate that the deposits are late
Pleistocene. However, an accurate chronology of deposition has not been
established due to discrepancies in the different dating methods.
Irrespective, the relative ages of significantly fossiliferous horizons at sites
QML796 and QML1396 are well established on the basis of superposition.
Additional dating is required to relate those horizons to fossiliferous horizons
at other sites, and such results may have significant implications relating to
the extinction of the Australian Pleistocene megafauna. Regardless, the data
allow a strict blitzkrieg hypothesis to be rejected because megafauna
extinction was not simultaneous in the Kings Creek catchment.
9) Comprehensive lithofacies, depositional environment, taphonomic, and
palaeoecologic analyses suggest that changing late Pleistocene Darling
Downs habitat and species diversity were most consistent with a climatically-
driven cause and occurred irrespective of potential human involvement.
258
REFERENCES
ALBERDI, M.T., MIOTTI, L. & PRADO, J.L. 2001. Hippidion saldiasi Roth,
(Equidae, Perissodactyla), at the Piedra Museo site (Santa Cruz,
Argentina): its implication for the regional economy and environmental
reconstruction. Journal of Archaeological Science. 28: 411-419.
ALEXANDER, R. MCN. 1998. All-time giants: the largest animals and their
problems. Palaeontology. 41: 1231-1245.
ALROY, J. 2001a. A multispecies overkill simulation of the end-Pleistocene
megafaunal mass extinction. Science. 292: 1893-1896.
ALROY, J. 2001b. In: Corrections and Clarifications. Science. 293: 2205.
ANDERSON, E. 1984. Who’s who in the Pleistocene: a mammalian bestiary.
In: Martin, P.S. & Klein, R.G. (Eds.) Quaternary Extinctions: A Prehistoric
Revolution, pp. 40-89. University of Arizona Press, Tucson.
ANDERSON, A. 1989. Mechanics of overkill in the extinctions of New Zealand
moas. Journal of Archaeological Science. 16: 137-151.
ANDREEV, A.A., SIEGERT, C., KLIMANOV, V.A., DEREVYAGIN, A.Y., SHILOVA, G.N.
& MELLES, M. 2002. Late Pleistocene and Holocene vegetation and climate
on the Taymr Lowland, Northern Siberia. Quaternary Research. 57: 138-
150.
ANDREWS, P. 1990. Owls, caves and fossils. University of Chicago Press.
Chicago.
ANDREWS, P., LORD, J.M. & NESBIT EVANS, E.M. 1979. Patterns of ecological
diversity in fossil and modern mammalian fauns. Biological Journal of the
Linnean Society. 11: 177-205.
APLIN, K. P. & ARCHER, M. 1987. Recent advances in marsupial systematics
with a new syncretic classification. In: Archer, M. (Ed.) Possums and
Opossums: Studies in Evolution, pp. xv-lxxii. Surrey, Beatty & Sons and
the Royal Zoological Society of New South Wales, Sydney.
ARAKEL, A.V. 1982. Genesis of calcrete in Quaternary soil profiles, Hutt and
Leeman Lagoons, Western Australia. Journal of Sedimentary Petrology.
52: 109-125.
ARAKEL, A.V. & MCCONCHIE, D. 1982. Classification and genesis of calcrete
and gypsite lithofacies in paleodrainage systems of inland Australia and
259
their relationship to carnotite mineralization. Journal of Sedimentary
Petrology. 52: 1149-1170.
ARCHER, M. 1974. New information about the Quaternary distribution of the
thylacine (Marsupialia, Thylacinidae) in Australia. Journal of the Royal
Society of Western Australia. 57: 43-49.
ARCHER, M. 1976a. Phascolarctid origins and the potential of the selenodont
molar in the evolution of diprotodont marsupials. Memoirs of the
Queensland Museum. 17: 367-371.
ARCHER, M. 1976b. Bluff Downs local fauna. In: Archer, M. & Wade, M.,
Results of the Ray E. Lemley expeditions, Part 1. The Allingham
Formation and a new Pliocene vertebrate fauna from northern
Queensland, pp. 383-397. Memoirs of the Queensland Museum. 17: 379-
397.
ARCHER, M. 1977. Origins and subfamilial relationships of Diprotodon
(Diprotodontidae, Marsupialia). Memoirs of the Queensland Museum. 18:
37-39.
ARCHER, M. 1978a. Quaternary vertebrate faunas from the Texas Caves of
southeastern Queensland. Memoirs of the Queensland Museum. 19: 61-
109.
ARCHER, M. 1978b. Modern fauna and flora of the Texas Caves area,
southeastern Queensland. Memoirs of the Queensland Museum 19, 111-
119.
ARCHER, M. 1981. Results of the Archbold Expeditions. No. 104. Systematic
revision of the marsupial dasyurid genus Sminthopsis Thomas. Bulletin of
the American Museum of Natural History. 168: 61-224.
ARCHER, M. 1984. Background to the search for Australia’s oldest mammals.
In: Archer, M. & Clayton, G. (Eds.) Vertebrate Zoogeography and
evolution in Australasia, pp. 517-565. Hesperian Press, Carlisle, Western
Australia.
ARCHER, M., & BARTHOLOMAI, A. 1978. Tertiary mammals of Australia: a
synoptic review. Alcheringa. 2: 1-19.
ARCHER, M., GODTHELP, H., HAND, S.J. & MEGIRIAN, D. 1989. Fossil mammals
of Riversleigh, northwestern Queensland: preliminary overview of
260
biostratigraphy, correlation and environmental change. Australian Zoology.
25: 29-65.
ARCHER, M. & HAND, S. 1984. Background to the search for Australia’s oldest
mammals. In: Archer, M. & Clayton, G. (Eds.) Vertebrate Zoogeography
and Evolution in Australia, pp. 517-565. Hesperian Press, Carlisle,
Western Australia.
ARCHER, M., PLANE, M.D. & PLEDGE, N.S. 1978. Additional evidence for
interpreting the Miocene Obdurodon insignis Woodburne and Tedford,
1975, to be a fossil platypus (Ornithorhynchidae: Monotremata) and a
reconsideration of the status of Ornithorhyncus agilis De Vis, 1885.
Australian Zoologist. 20: 9-27.
ARROYO-CABRALES, J., POLACO, O.J. & JOHNSON, E. 2006. A preliminary view
of the coexistence of mammoth and early people in México. Quaternary
International. 142-143: 79-86.
ASHBY, E., LUNNEY, D., ROBERTSHAW, J. & HARDEN, R. 1990. Distribution and
status of bandicoots in New South Wales. In: Seebeck, J.H., Brown, P.R.,
Wallis, R.L. & Kemper, C.M. (Eds.) Bandicoots and Bilbies, pp. 43-50.
Surrey Beatty and Sons, New South Wales.
ASHKENAZY, Y. & TZIPERMAN, E. 2004. Are the 41 kyr glacial oscillations a
linear response to Milankovitch forcing? Quaternary Science Reviews. 23:
1879-1890.
Australian Bureau of Meteorology. Internet website: http://www.bom.gov.au/
AYLIFFE, L.K., MARIANELLI, P.C., MORIARTY, K.C., WELLS, R.T., MCCOLLUCH,
M.T., MORTIMER, G.E. & HELLSTROM, J.C. 1998. 500 ka precipitation record
from southeastern Australia: Evidence for interglacial relative aridity.
Geology. 26: 147-150.
BADGLEY, C. 1986. Counting individuals in mammalian fossil assemblages
from fluvial environments. Palaios. 1: 328-338.
BAIRD, R. 1986. Tasmanian native hen Gallinula mortierii: The first late
Pleistocene record from Queensland. The Emu. 86: 121-122.
BAIRD, R.F. 1991. The taphonomy of late Quaternary cave localities yielding
vertebrate remains in Australia, Chapter 10. In: Vickers-Rich, P.,
Monoghan, J. M., Baird, R. F., & Rich, T. H. (Eds.) Vertebrate
261
Palaeontology of Australasia, pp. 267-309. Pioneer Design Studio Pty Ltd
and Monash University Publications Committee, Melbourne.
BAK, P. 1996. How nature works: the science of self-organized criticality.
Springer Verlag, New York.
BARNOSKY, A.D. 2001. Distinguishing the effects of the Red Queen and Court
Jester on Miocene mammal evolution in the northern Rocky Mountains.
Journal of Vertebrate Paleontology. 21: 172-185.
BARNOSKY, A.D., BELL, C.J., EMSLIE, S.D., GOODWIN, H.T., MEAD, J.I.,
REPENNING, C.A., SCOTT, E. & SHABEL, A.B. 2004a. Exceptional record of
mid-Pleistocene vertebrates helps differentiate climatic from
anthropogenic ecosystem perturbations. Proceedings of the National
Academy of Sciences of the United States of America. 101: 9297-9302.
BARNOSKY, A.D., KOCH, P.L., FERANEC, R.S., WING, S.L. & SHABEL, A.B.
2004b. Assessing the causes of late Pleistocene extinctions on the
continents. Science. 306: 70-75.
BARNOSKY, C.W. 1985. Late Quaternary vegetation in the southwestern
Columbia Basin, Washington. Quaternary Research. 23: 109-122.
BARROWS, T.T., STONE, J.O., FIFIELD, L.K. & CRESSWELL, R.E. 2002. The
timing of the last glacial maximum in Australia. Quaternary Science
Reviews. 21: 159-173.
BARTHOLOMAI, A. 1963. Revision of the extinct macropodid genus Sthenurus
Owen in Queensland. Memoirs of the Queensland Museum. 14: 51-76.
BARTHOLOMAI, A. 1966. The type specimens of some of De Vis’s species of
fossil Macropodidae. Memoirs of the Queensland Museum. 14: 115-125.
BARTHOLOMAI, A. 1967. Troposodon, a new genus of fossil Macopodinae
(Marsupialia). Memoirs of the Queensland Museum. 15: 21-33.
BARTHOLOMAI, A. 1970. The extinct genus Propcoptodon Owen (Marsupialia;
Macropodidae) in Queensland. Memoirs of the Queensland Museum. 15:
213-234.
BARTHOLOMAI, A. 1972. Some upper cheek teeth in Propleopus oscillans (De
Vis). Memoirs of the Queensland Museum. 15: 213-233.
BARTHOLOMAI, A. 1973a. The genus Protemnodon Owen (Marsupialia;
Macropodidae) in upper Cainozoic deposits of Queensland. Memoirs of
the Queensland Museum. 16: 309-363.
262
BARTHOLOMAI, A. 1973b. Fissuridon pearsoni, a new fossil macropod
(Marsupialia) from Queensland. Memoirs of the Queensland Museum. 16:
365-368.
BARTHOLOMAI, A. 1975. The genus Macropus Shaw (Marsupialia;
Macropodidae) in the upper Cainozoic deposits of Queensland. Memoirs
of the Queensland Museum. 17: 195-235.
BARTHOLOMAI, A. 1976a. The genus Wallabia Troussart (Marsupialia;
Macropodidae) in the upper Cainozoic deposits of Queensland. Memoirs
of the Queensland Museum. 17: 373-378.
BARTHOLOMAI, A. 1976b. Notes of the fossiliferous Pleistocene fluviatile
deposits of the eastern Darling Downs. Bureau of Mineral Resources,
Geology and Geophysics. Bulletin. 166: 153-154.
BARTHOLOMAI, A. & WOODS, J.T. 1976. Notes of the vertebrate fauna of the
Chinchilla Sand. Bureau of Mineral Resources, Geology and Geophysics.
Bulletin. 166: 151-152.
BARTHOLOMAI, A. 1977. The fossil vertebrate fauna from Pleistocene deposits
at Cement Mills, Gore, southeastern Queensland. Memoirs of the
Queensland Museum. 18: 41-51.
BAYNES, A. 1999. The absolutely last remake of Beau Geste: yet another
review of the Australian megafaunal radiocarbon dates. Abstracts of the
6th CAVEPS, July, 1997. Records of the Western Australian Museum.
Supplement 57: 391.
BECK, M.W. 1996. On discerning the cause of late Pleistocene megafaunal
extinction. Paleobiology. 22: 91-103.
BEESLEY, P.L. ROSS, G.J.B. & WELLS, A. 1998. Mollusca: The Southern
Synthesis. Fauna of Australia. CSIRO Publishing. Melbourne. 5.
BEHRENS, E.W. & WATSON, R.L. 1969. Differential sorting of pelecypod valves
in the swash zone. Journal of Sedimentary Petrology. 39: 227-250.
BEHRENSMEYER, A.K. 1975. The taphonomy and paleoecology of Plio-
Pleistocene vertebrate assemblages cast of Lake Rudolf, Kenya. Bulletin
of the Museum of Comparative Zoology. 146: 473-578.
BEHRENSMEYER, A.K. 1978. Taphonomic and ecologic information from bone
weathering. Paleobiology: 4: 150-162.
263
BEHRENSMEYER, A.K. 1982. Time resolution in fluvial vertebrate
assemblages. Paleobiology. 8: 211-228.
BEHRENSMEYER, A.K. 1988. Vertebrate preservation in fluvial channels.
Palaeogeography, Palaeoclimatology, Palaeoecology. 63: 183-199.
BEHRENSMEYER, A.K. 1990. Transport-hydrodynamics: bones. In: Briggs,
D.E.G. & Crowther, P.R. (Eds.). Palaeobiology: a Synthesis, pp. 232-235.
Blackwell Scientific Publications, Oxford.
BEHRENSMEYER, A. K, STAYTON, C. T. & CHAPMAN, R. E. 2003. Taphonomy
and ecology of modern avifaunal remains from Amboseli Park, Kenya.
Paleobiology. 29: 52-70.
BELL, H.M. 1973. The ecology of three macropod marsupial species in an
area of open forest and savannah woodland in north Queensland,
Australia. Mammalia. 37: 527-544.
BENGTSSON, L., BOTZET, M. & ESCH, M. 1996.Will greenhouse gas-induced
warming over the next 50 years lead to a higher frequency and greater
intensity of hurricanes? Tellus. 48A: 175-196.
BENNET, G. 1872. A trip to Queensland in search of fossils. Annals and
Magazine of Natural History. 9: 314.
BENNETT, G.F. 1876. Notes of Rambles in Search of fossils on the Darling
Downs. Government Printer. Australia.
BENSON, J.S. & REDPATH, P.A. 1997. The nature of pre-European native
vegetation in south-eastern Australia: a critique of Ryan, D.G., Ryan, J.R.
and Starr, B.J. (1995). The Australian landscape- observations of
explorers and early settlers. Cunninghamia. 5: 285-328.
BENSON, J.S. & REDPATH, P.A. 1998. A response to Flannery’s reply.
Cunninghamia. 5: 782-785.
BERGER, A. & LOUTRE, M.F. 2002. An exceptionally long interglacial ahead?
Science. 297: 1287-1288.
BEST, J.L., ASHWORTH, P.J., BRISTOW, C.S. & RODEN, J. 2003. Three-
dimensional sedimentary architecture of a large, mid-channel sand braid
bar, Jamuna River, Bangladesh. Journal of Sedimentary Research. 73:
516-530.
BLACK, K. 1997. A new species of Palorchestidae (Marsupialia) from the late
Middle to early Late Middle Miocene Encore Local Fauna, Riversleigh,
264
northwestern Queensland. Memoirs of the Queensland Museum. 41: 181-
185.
BOER, G.J., FLATO, G. & RAMSDEN, D. 2000. A transient climate change
simulation with greenhouse gas and aerosol forcing: projected climate for
the 21st century. Climate Dynamics. 16: 427-450.
BOESKOROV, G.G. 2006. Arctic Siberia: refuge of the Mammoth fauna in the
Holocene. Quaternary International. 142-143: 119-123.
BOIE, F. 1827. Bemerkungen über Merrem's Versuch eines Systems der
Amphibien. 1ste Lieferung: Ophidier - Isis, oder Encyclopädische Zeitung
von Oken, 20 (6): columns 508-566.
BONAPARTE, C.L.J.L. 1838. Synopsis vertebratorum systematis. Nuovi Annali
delle Scienze Naturali, Bologna. 2: 105-133.
BOUCOT, A.J., BRACE, W. & DEMAR, R. 1958. Distribution of brachiopod and
pelecypod shells in currents. Journal of Sedimentary Petrology. 328: 321-
332.
BOWDICH, T.E. 1821. An analysis of the natural classifications of Mammalia
for the use of students and travelers. J. Smith. Paris.
BOWLER, J.M. 1986. Spatial variability and hydrologic evolution of Australian
lake basins: analogue for Pleistocene hydrologic change and evaporite
formation. Palaeogeography, Palaeoclimatology, Palaeoecology. 54: 21-
41.
BOWLER, J.M., JOHNSTON, H., OLLEY, J.M., PRECOTT, J.R., ROBERTS R.G.,
SHAWCROSS, W. & SPOONER, N.A. 2003. New ages for human occupation
and climatic change at Lake Mungo, Australia. Nature. 421: 837-840.
BOWLER, J.M., WYRWOLL, K.H. & LU, Y. 2001. Variations of the northwest
Australian summer monsoon over the last 300,000 years: the
paleohydrological record of the Gregory (Mulan) Lakes System.
Quaternary International. 83-85: 63-80.
BOWMAN, D.M.J.S. 1998. Tansley Review No. 101. The impact of Aboriginal
landscape burning on the Australian biota. New Phytologist.140: 385-410.
BOWMAN, D.M.J.S. 2002. The Australian summer monsoon: a biogeographic
perspective. Australian Geographical Studies. 40: 261-277.
BRAITHWAITE, R.W. 1995. Southern brown bandicoot. In: Strahan, R. (
265
Ed.) The Mammals of Australia, pp. 176-177. New Holland Publishers,
Australia.
BRENCHLEY, P.J. & NEWALL, G. 1970. Flume experiments on the orientation
and transport of models and shell valves. Palaeogeography,
Palaeoclimatology and Palaeoecology. 7: 185-220.
BRITTON, J.C. & MORTON, B. 1982. A dissection guide, field and laboratory
manual for the introduced bivalve Corbicula fluminea. Malacologia Review
Supplement. 3: 1-82.
BRAITHWAITE, R.W. 1995. Southern brown bandicoot. In: Strahan, R. (Ed.)
The Mammals of Australia, pp. 176-177. New Holland Publishers, Sydney,
Australia.
BROOK, B.W. & BOWMAN, D.M.J.S. 2002. Explaining the Pleistocene
megafaunal extinctions: models, chronologies and assumptions.
Proceedings of the National Academy of Sciences of the United States of
America. 99: 14624-14627.
BROOK, B.W. & BOWMAN, D.M.J.S. 2004. The uncertain blitzkrieg of
Pleistocene megafauna. Journal of Biogeography. 31: 517-523.
BROTHWELL, D. & JONES, R. 1978. The relevance of small mammal studies to
archaeology. In: Brothwell, D.R., Thomas, K.D. & Clutton-Brock, J. (Eds.)
Research Problems in Zooarachaology, pp. 47-57. Occasional
Publications 3. Institute of Archaeology. London.
BROWN, D.S. 1981. Observations of the Planorbinae from Australia and New
Guinea. Journal of the Malacological Society of Australia. 5: 67-80.
BROWN, P., SUTIKNA, T., MORWOOD, M., SOEJONO, R.P., JATMIKO, E., SAPTOMO,
E.W. & ROKUS AWE DUE. 2004. A new small-bodied hominin from the late
Pleistocene of Flores, Indonesia. Nature. 431: 1087-1091.
BROWN, S.P. & WELLS, R.T. 2000. A middle Pleistocene vertebrate fossil
assemblage from Cathedral Cave, Naracoorte, South Australia.
Transactions of the Royal Society of South Australia. 124: 91-104.
BULTE, E., HORAN, R.D. & SHOGREN, J.F. 2006. Megafauna extinction: a
paleoeconomic theory of human overkill in the Pleistocene. Journal of
Economic Behavior and Organization. 59: 297-323.
266
BURGER, J. & SNODGRASS, J. 2001. Metal levels in southern leopard frogs
from the Savannah River Site: Location and body compartment effects.
Environmental Research. 86: 157-166.
BURNEY, D.A., ROBINSON, G.S. & PIGOTT BURNEY, L. 2003. Sporormiella and
the late Holocene extinctions in Madagascar. Proeedings of the National
Academy of Sciences of the United States of America. 100: 10800-10805.
BURNEY, D.A., PIGOTT BURNEY, L., GODFREY, L.R., JUNGERS, W.L., GOODMAN,
S.M., WRIGHT, H.T. & JULL, A.J. 2004. A chronology for late Pleistocene
Madagascar. Journal of Humans Evolution. 47: 25-63.
BURNEY, D.A. & FLANNERY, T.F. 2005. Fifty millennia of catastrophic
extinctions after human contact. Trends in Ecology and Evolution. 20:
395-401.
BURNEY, D.A. & FLANNERY, T.F. 2005. Response to Wroe et al.: Island
extinctions versus continental extinctions. Trends in Ecology and
Evolution. 21: 63-64.
BUZAS, M.A. HAYEK, L-A.C., 2005. On richness and eveness within and
between communities. Paleobiology. 31: 199-220.
CADÉE, G.C. 1968. Molluscan biocoenoses and thanatocoenoses in the Ria
de Arosa, Galicia, Spain. Zoologische Verhandelingen uitgegeven door
het Rijksmuseum van Natuulijke Historie te Leiden. 95: 1-121.
CALABY, J.H. 1976. Some biogeographical factors relevant to the Pleistocene
movement of man in Australasia. In: Kirk, R.L. & Thorne, A.G. (Eds.) The
Origin of the Australians, pp.23-28. Australian Institute of Aboriginal
Studies, Canberra.
CALLAGHAN, T.V., BJÖRN, L.O., CHERNOV, Y., CHAPIN, T., CHRISTENSEN, T.R.,
HUNTLEY, B., IMS, R.A., JOHANSSON, M., JOLLY, D., JONASSON, S.,
MATVEYEVA, N., PANIKOV, N., OECHEL, W. & SHAVER, G. 2004. Past
changes in Arctic terrestrial ecosystems, climate and UV radiation: climate
change and UV-B impacts on Arctic tundra and polar desert ecosystems.
Ambio. 33: 398-403.
CANNON, M.D. 2004. Geographic variability in North American mammal
community richness during the terminal Pleistocene. Quaternary Science
Reviews. 23: 1099-1123.
267
CHAPLIN, R.E. 1971. The Study of Animal Bones From Archaeological Sites.
Seminar Press, London.
CHOQUENOT, D. & BOWMAN, D.M.J.S. 1998. Marsupial megafauna, Aborigines
and the overkill hypothesis: application of predator-prey models to the
question of Pleistocene extinction in Australia. Global Ecology and
Biogeography Letters. 7: 167-180.
CLARK, R.L.1983. Pollen and charcoal evidence for the effects of Aboriginal
burning on the vegetation of Australia. Archaeology in Oceania. 18: 32-37.
CLEMENTS, F.E. 1904. The Development and Structure of Vegetation.
Botanical Seminar VII. Studies in the Vegetation of the State III. Botanical
Survey of Nebraska, University of Nebraska.
CLEMENTS, F.E. 1916. Plant succession: an analysis of the development of
vegetation. Carnegie Institution of Washington, Washington.
COGGER, H.G., CAMERON, E.E. & COGGER, H.M. 1983. Amphibia and Reptilia.
Zoological Catalogue of Australia 1, Australian Government Publishing
Service, Canberra.
COGGER, H.G. 2000. Reptiles and Amphibians of Australia. 6th Edition. Reed
Books. Frenchs Forest.
CONRAD, R.A. 1850. Descriptions of new species of freshwater shells.
Proceedings of the Natural Sciences Philadelphia. 5: 10-11.
CORBETT, L. 1995. The Dingo in Australia and Asia. University of New South
Wales Press, Sydney.
COVACEVICH, J.A & COUPER, P.J. 1991. The reptile records. In: Ingram, G.J. &
Raven, R.J. (Eds.) An Atlas of Queensland’s Frogs, Reptiles, Birds and
Mammals, pp. 45-140. Board of Trustees of the Queensland Museum,
Queensland.
COVACEVICH, J.A. & EASTON, A. 1974. Rats and Mice in Queensland.
Queensland Museum, Brisbane.
CUVIER, G.L.C.F.D. 1797. Tableau élémentarie de l’histoire naturelle des
animaux. Paris. XVI+170 p., 14pl.
CUVIER, G.L.C.F.D. 1817. Le règne animal distribuè d’apres son
organisation, pour servir de base a l’histoire naturelle des animaux et
d’introduction à l’anatomie comparee. Deterville, Paris. 1: 540.
268
CUVIER, G.L.C.F.D. 1837. In: Geoffroy (Saint-Hilaire), É. & Cuvier, F. Histoire
Naturelle des Mammifères, avec figures originales, coloriées, dessinées
d’après des animaux vivants. Volume quatrième. Livr. 70. Blaise, Paris,
France.
DAWSON, L. & AUGEE, M. L. 1997. The Late Quaternary sediments and fossil
vertebrate fauna from Cathedral Cave, Wellington Caves, New South
Wales. Proceedings of the Linnean Society of New South Wales. 117: 51-
78.
DAVIS, S.J.M. 1981. The effects of temperature change and domestication on
the body size of late Pleistocene to Holocene mammals in Israel.
Paleobiology. 7: 101-114.
DENNIS, A.J. & JOHNSTON, P.M. 1995. Rufous Bettong. In: Strahan, R. (Ed.)
The Mammals of Australia, pp 285-287. New Holland Publishers, Sydney,
Australia.
DESHAYES, G.P. 1830. Encyclopédie Méthodique. Historie naturelle des vers.
Paris. Agasse. 2: 1-136.
DESMAREST, A.G. 1817. Nouveau Dictionnaire d’Histoire Naturelle, appliqué
aux arts, á l’agriculture, á l’économie rurale et domestique, á la medicine,
etc. Par société de naturalistes et d’agricukteurs. Nouveau Édn presqu’
entièrement refondue et considérablement augmentée. Paris: Deterville
Tom. 16: 595.
DE VIS, C.W. 1885a. In: Annual Report Queensland Museum 1884.
Queensland Museum.
DE VIS, C.W. 1885b. On an extinct monotreme- Ornithorhynchus agilis. Daily
Observer, April 11. 2.
DE VIS, C.W. 1895. A review of the fossil jaws of the Macropodidae in the
Queensland Museum. Proceedings of the Linnean Society of New South
Wales. 10: 75-133.
DIAMOND, J.M. 1989a. The present, past and future of human-caused
extinction. Philosophical Transactions of the Royal Society of London.
Series B. Biological Sciences. 325: 469-476.
DIAMOND, J.M. 1989b. Quaternary megafaunal extinctions: variations on a
theme by Paganini. Journal of Archaeological Science. 16: 167-175.
DIAMOND, J.M. 2001. Australia’s last giants. Nature. 411: 755-757.
269
DIAMOND, J.M. 2004. The astonishing micropygmies. Science. 306: 2047-
2048.
DINIZ-FILHO, J.A.F. 2004. Macroecological analysis support an overkill
scenario for late Pleistocene extinctions. Brazilian Journal of Biology. 34:
407-414.
DIXON, J.M. 1989. Thylacinidae. In: Walton, D.W. & Richardson, B.J. (Eds.)
Fauna of Australia. Mammalia, Vol. 1B. pp. 549-559. Australian
Government Publishing Service, Canberra.
DODSON, J., FULLAGAR, R., FURBY, J., JONES, R. & PROSSER, I. 1993. Humans
and megafauna in a late Pleistocene environment from Cuddie Springs,
north-western New South Wales. Archaeology in Oceania. 28: 94-99.
DODSON, P. 1971. Sedimentology and taphonomy of the Oldman Formation
(Campanian), Dinosaur Provincial Park, Alberta (Canada).
Palaeogeography, Palaeoclimatology, Palaeoecology. 10: 21-74.
DODSON, P. 1973. The significance of small bones in paleoecological
interpretation. Contributions to Geology, University of Wyoming. 12: 15-
19.
DOORMAN, C.F. & WOODIN, S.J. 2002. Climate change in the Arctic: using
plant functional types in a meta-analysis of field experiments. Functional
Ecology. 16: 4-17.
DORTCH, C. E. & MERRILEES, D. 1971. A salvage excavation in Devil’s Lair,
Western Australia. Journal of the Royal Society of Western Australia: 54:
103-113.
DUNCAN, R.P. & BLACKBURN, T.M. 2004. Extinction and endemism in the New
Zealand avifauna. Global Ecology and Biogeography. 13: 509-517.
DUNCAN, R.P., BLACKBURN, T.M. & WORTHY, T.H. 2002. Prehistoric bird
extinctions and human hunting. Proceedings of the Royal Society of
London, B. 269: 517-521.
DUNKER, A.G. 1848. Diagnoses specirum novarum generis Planorbis
collection is Cumingianae. Proceedings of the Royal Society of London.
1848: 40-43.
DUPONT, L.M., JAHNS, S., MARRET, F. & NING, S. 2000. Vegetation change in
equatorial West Africa: time slices for the last 150 ka. Palaeogeography,
Palaeoclimatology, Palaeoecology. 155: 95-122.
270
EATON, J.G., KIRKLAND, J.I & DOI, K. 1989. Evidence of reworked Cretaceous
fossils and their bearing on the existence of Tertiary dinosaurs. Palaios. 4:
281-286.
ERICKSON, G. M., DE RICQLÈS, A., DE BUFFRÉNIL, V., MOLNAR, R.E. & BAYLESS,
M.A. 2003. Vermiform bones and the evolution of gigantism in Megalania-
how a reptilian fox became a lion. Journal of Vertebrate Paleontology. 23:
966-970.
FENSHAM, R.J. 1998. The grassy vegetation of the Darling Downs, south-
eastern Queensland, Australia. Floristics and grazing effects. Biological
Conservation. 84: 301-310.
FENSHAM, R.J. & FAIRFAX, R.J. 1997. The use of the land survey record to
reconstruct pre-European vegetation patterns of the Darling Downs,
Queensland, Australia. Journal of Biogeography. 24: 827-836.
FICCARELLI, G., AZZAROLI, A., BERTINI, A., COLTORTI, M., MAZZA, P.,
MEZZABOTTA, C., MORENO ESPINOSA, M., ROOK, L. & TORRIE, D. 1997.
Hypothesis on the cause of the extinction of the South American
mastodonts. Journal of South American Earth Sciences. 10: 29-38.
FIEDEL, S.J. 2005. Man’s best friend- mammoth’s worst enemy? A
speculative essay on the role of dogs in Paleoindian colonization and
megafaunal extinctions. World Archaeology. 37: 11-25.
FIEDEL S. & HAYNES, G. 2004. A premature burial: comments on Grayson and
Meltzer’s “Requiem for overkill”. Journal of Archaeological Science. 31:
121-131.
FIELD, J. & DODSON, J. 1999. Late Pleistocene megafauna and archaeology
from Cuddie Springs, south-eastern Australia. Proceedings of the
Prehistoric Society. 65: 275-301.
FIELD, J., DODSON, J.R. & PROSSER, I.P. 2002. A Late Pleistocene vegetation
history from the Australian semi-arid zone. Quaternary Science Reviews.
21: 1023-1037.
FIELD, J. & FULLAGAR, R. 2001. Archaeology and Australian megafauna.
Science. 294: 7a.
FIFIELD, L.K. BIRD, M.I., TURNEY, T.S.M., HAUSLAFDEN, P.A., SANTOS, G.M. & DI
TADA, M.L. 2001. Radiocarbon dating of the human occupation of
271
Australia prior to 40 ka BP- successes and pitfalls. Radiocarbon. 43:
1139-1145.
FISCHER, G. 1803. Das Nationalmuseum der Naturgeschichte zu Paris. Von
seinem ersten Ursprunge bis zu seinem jetzigen Glanze. Zweiter Band.
Schilderung der naturhistorischen Sammlungen. Frankfurt am Main.
FISCHER, P. 1884. Manuel de conchyliologie et de paleontologie
conchliologique, ou historie naturelle des mollusques vivants et fossils.
Paris. 7: 609-688.
FITZINGER, L. J., 1843. Systema reptilum. Braümuller und Seidel, Vienna.
FLANNERY, T.F. 1990. Pleistocene faunal loss: implications of the aftershock
for Australia’s past and future. Archaeology in Oceania. 25: 45-55.
FLANNERY, T.F. 1994. The Future Eaters: An Ecological History of the
Australasian Lands and People. Reed Books, Sydney.
FLANNERY, T.F. 1995. The Mammals of New Guinea. Revised and Updated
Edition. Reed Books, Chatswood, New South Wales.
FLANNERY, T.F. 1998. A reply to Benson and Redpath (1997). Cunninghamia.
5: 779-781.
FLANNERY, T.F. 1999a. Debating extinction. Science. 283: 182-183.
FLANNERY, T.F. 1999b. The Pleistocene mammal fauna of Kelangurr Cave,
central montane Irian Jaya, Indonesia. Records of the Western Australian
Museum. Supplement 57: 341-350.
FLANNERY, T.F. & ARCHER, M. 1982. The taxonomy and distribution of
Macropus (Fissuridon) pearsoni (Marsupialia: Macropodidae). Australian
Mammalogy. 5: 261-265.
Flannery, T.F. & Archer, M. 1983. Revision of the genus Troposodon
Bartholomai (Macropodidae, Marsupialia). Alcheringa. 7: 263-279.
FLOOD, J. 1995. Archaeology of the Dreamtime: The Story of Prehistoric
Australia and Its People. Revised Edition. Angus & Robertson, Sydney.
FORSTEN, A. 1991. Size decrease in Pleistocene-Holocene true or caballoid
horses in Europe. Mammalia. 55: 407-420.
FORSTER, M.A. 2003. Self-organised instability and megafaunal extinctions in
Australia. Oikos. 103: 235-239.
FREEDMAN, L. 1967a. Skull and tooth variation in the genus Perameles. Part
I: Anatomical features. Records of the Australian Museum. 27: 147-166.
272
FREEDMAN, L. 1967b. Skull and tooth variation in the genus Perameles. Part
III: Metrical features of P. gunnii and P. bougainville. Records of the
Australian Museum. 27: 197-212.
FRIEND, A.J. 1990. Status of bandicoots in Western Australia. In: Seebeck,
J.H., Brown, P.R., Wallis, R.L., Kemper, C.M. (Eds.) Bandicoots and
Bilbies, pp. 73-84. Surrey Beatty & Sons, Sydney.
FRIEND, J. A. & BURBIDGE, A. A. 1995. Western barred bandicoot. In: Strahan,
R. (Ed.). The Mammals of Australia, pp. 178-180. New Holland
Publishers, Sydney, Australia.
FRISSON, G.C. 1998. Paleoindian large mammal hunters on the plains of
North America. Proceedings of the National Academy of Sciences of the
United States of America. 95: 14576-14583.
FROST, D.R. 1985. Amphibian Species of the World. Allen Press &
Association of Systematic Collections, Lawrence, Kansas.
FULLAGAR, R. & FIELD, J. 1997. Pleistocene seed-grinding implements from
the Australian arid zone. Antiquity. 71: 300-307.
GAFFNEY, E.S. 1981. A review of the fossil turtles of Australia. American
Museum Novitates. 2720: 1-38.
GALLAGHER, S.J., GREENWOOD, D.R., TAYLOR, D., SMITH, A.J., WALLACE, M.W.
& HOLDGATE, G.R. 2003. The Pliocene climatic and environmental
evolution of southeastern Australia: evidence from the marine and
terrestrial realm. Palaeogeography, Palaeoclimatology, Palaeoecology.
193: 349-382.
GARROD, A.H. 1875. On the kangaroo called Halmaturus luctuosus by
D’Albertis and its affinities. Proceedings of the Zoological Society of
London. 1875. 48-59.
GEOFFROY (SAINT-HILAIRE), É. 1796. Dissertation sur les animaux à bourse.
Magasin Encyclopaedique. 3: 445-472.
GEOFFROY, (SAINT-HILAIRE) É. 1804. Mémoire sur un nouveau genre de
mammifères à bourse, nommè Péramèles. Annales de la Musée Natioanl
d’ Histoire Naturelle de Paris. 4: 56-64.
GILL, E.D. 1978. Geology of the late Pleistocene Talgai cranium from S.E.
Queensland, Australia. Archaeology and Physical Anthropology in
Oceania. 13: 177-197.
273
GILL, T. 1872. Arrangement of the families of mammals with analytical table.
Smithsonian Miscellaneous Collection. 2: I-VI, 1-98.
GILLESPIE, R. 2002. Dating the first Australians. Radiocarbon. 44: 455-472.
GILLESPIE, R. & DAVID, B. 2002. The importance, or impotence, of Cuddie
Springs. Australasian Science. 22(9): 42-43.
GLEASON, H.A. 1926. The individualistic concept of the plant association.
Bulletin of the Torrey Botany Club. 53: 7-26.
GLASBY, C. J., ROSS, G.J.B. & BEESLEY, P.L. 1993. Fauna of Australia. Vol. 2A
Amphibia and Reptilia. Australian Government Publishing Service.
Canberra.
GLAUERT, L. 1926. A list of Western Australian fossil. Supplement No. 1.
Bulletin of the Geological Survey of Western Australia. 88: 36-77.
GODTHELP, H. 1990. Pseudomys vandycki, a Tertiary murid from Australia.
Memoirs of the Queensland Museum. 28: 171-173.
GOLDFUSS, G.A. 1820. Handbuch der Zoologie. J. L. Schrag, Nürnberg.
GOLLAN, K. 1984. The Australian dingo: in the shadow of man. In: Archer, M.
& Clayton, F. (Eds.) Vertebrate Zoogeography and Evolution in Australia,
pp. 921-927. Hesperian Press, Perth.
GONZALEZ, S., KITCHENER, A.C. & LISTER, A.M. 2000. Survival of the Irish elk
into the Holocene. Nature. 405: 753-754.
GORDON, G., HALL, L.S. & ATHERTON, R.G. 1990. Status of bandicoots in
Queensland. In: Seebeck, J.H., Brown, P.R., Wallis R.L., & Kemper C. M.
(Eds.). Bandicoots and Bilbies, pp. 37-42. Surrey Beatty and Sons, New
South Wales.
GORDON, G. & HULBERT, A.J. 1989. Peramelidae. In: Walton, D.W. &
Richardson, B.J. (Eds.) Fauna of Australia. Mammalia, Vol. 1B. pp. 603-
624. Australian Government Publishing Service, Canberra.
GORDON, L.J., STEFFEN, W., JONSSON, B.F., FOLKE, C., FALKENMARK, M. &
JOHANNESSEN, A. 2005. Human modification of global water vapor flows
from the land surface. Proceedings of the National Academy of Sciences
of the United States of America. 102: 7612-7617.
GOTT, B. 2005. Aboriginal fire management in south-eastern Australia: aims
and frequency. Journal of Biogeography. 32: 1203-1208.
274
GRAHAM, R.W. & LUNDELIUS, E. L. JR. 1984. Coevolutionary disequilibrium
and Pleistocene extinctions. In: Martin, P.S. & Klein, R.G. (Eds.)
Quaternary Extinctions: A Prehistoric Revolution, pp. 223-249. University
of Arizona Press, Tucson.
GRAHAM, R. W, LUNDELIUS E. L. JR., GRAHAM, M. A., SCHROEDER, E. K.,
TOOMEY, R. S. III, ANDERSON, E. BARNOSKY, A. D., BURNS, J. A., CHURCHER,
C. S., GRAYSON, D. K., GUTHRIE, R. D., HARINGTON, C. R., JEFFERSON, G. T.,
MARTIN, L. D., MCDONALD, H. G., MORLAN, R. E., SEMKEN, H. A. JR., WEBB,
S. D., WERDELIN, L. & WILSON, M. C. (FAUNMAP Working Group) 1996.
Spatial response of mammals to late Quaternary environmental
fluctuations. Science. 272: 1601-1606.
GRAY, J.E. 1821. On the natural arrangement of vertebrose animals. London
Medical Repository. 15: 296-310.
GRAY, J.E. 1825a. A synopsis of the genera of reptiles and Amphibia, with a
description of some new species. Annals of Philosophy. 10: 193-217.
GRAY, J.E. 1825b. Outline of an attempt at the disposition of the Mammalia
into tribes and families with a list of the genera apparently appertaining to
each tribe. Annals of Philosophy. 10: 337-344.
GRAY, J.E. 1832. Characters of a new genus of Mammalia, and of a new
genus and two new species of lizards, from New Holland. Proceedings of
the Zoological Society of London. 1832: 39-40.
GRAY, J.E. 1838. On a new species of Perameles. Proceedings of the
Zoological Society of London 1838: 1.
GRAY, J.E. 1842. Descriptions of some hitherto unrecorded species of
Australian reptiles and batrachians. In: Gray, J.E. (Ed.) Zoological
Miscellany, pp. 51-57. Treuttel, Wärtz & Co, London.
GRAY, J.E. 1847. A list of the genera of recent Mollusca, their synonyma and
types. Proceedings of the Zoological Society of London. 15: 129-219.
GRAYSON, D.K. 1989. The chronology of North America late Pleistocene
extinctions. Journal of Archaeological Science. 16: 153-165.
GRAYSON, D.K. 1991. Late Pleistocene extinctions in North America:
taxonomy, chronology, and explanations. Journal of World Prehistory. 5:
193-232.
275
GRAYSON, D.K. 2001. The archaeological record of human impacts on animal
populations. Journal of World Prehistory. 15: 1-68.
GRAYSON, D.K. & MELTZER, D.J. 2002. Clovis hunting and large mammal
extinction: a critical review of the evidence. Journal of World Prehistory.
16: 313-359.
GRAYSON, D.K. & MELTZER, D.J. 2003. A requiem for North American overkill.
Journal of Archaeological Science. 30: 585-593.
GRAYSON, D.K. & MELTZER, D.J. 2004. North American overkill continued?
Journal of Archaeological Science. 31: 133-136.
GREER, A.E. 1979. A phylogenetic subdivision of Australian skinks. Records
of the Australian Museum. 32: 339-371.
GREER, A.E. 1989. The Biology and Evolution of Australian Lizards. Surrey,
Beatty and Sons. Chipping North. Australia.
GRÜN R., SPOONER, N.A., THORNE, A., MORTIMER, G., SIMPSON, J.J.,
MCCULLOCH, M.T., TAYLOR, L., CURNOE, D. 2000. Age of the Lake Mungo 3
skeleton, reply to Bowler & Magee and to Gillespie & Roberts. Journal of
Human evolution. 38: 733-741.
GÜNTHER, A. 1858. Catalogue of the Batrachia Salientia in the Collection of
the British Museum. British Museum, London.
GUTHRIE, R.D. 1984. Mosaics, allelochemics and nutrients: an ecological
theory of late Pleistocene megafaunal extinctions. In: Martin, P.S. & Klein,
R.G. (Eds.) Quaternary Extinctions: A Prehistoric Revolution, pp. 259-298.
University of Arizona Press. Tucson.
GUTHRIE, R.D. 2003. Rapid body size decline in Alaskan Pleistocene horses
before extinction. Nature. 426: 169-171.
GUTHRIE, R.D. 2004. Radiocarbon evidence of mid-Holocene mammoths
stranded on an Alaskan Bering Sea island. Nature. 429: 746-749.
HAMMER, Ø., HARPER, D. A. T., RYAN, P. D. 2001. PAST: Palaeontological
statistics software package for education and data analysis.
Palaeontologica Electronica. 4(1): 1-9.
HARDWICKE, M.G. & GRAY, J.E. 1827. A synopsis of the species of saurian
reptiles, collected in India by Major-General Hardwicke. Zoological Journal
(London). 3: 213-229.
276
HARRIS, G.P. 1808. Description of two new species of Didelphis from Van
Diemens’ Land. Transactions of the Linnean Society of London. 9: 174-
178.
HAYNES, G. 1980. Evidence of carnivore gnawing on Pleistocene and Recent
mammalian bones. Paleobiology. 6: 341-351.
HAYNES, G. 1983. A guide for differentiating mammalian carnivore taxa
responsible for gnawing damage to herbivore limb bones. Paleobiology. 9:
164-172.
HAYNES, G. 2006. Mammoth landscapes: good country for hunter-gatherers.
Quaternary International. 142-143: 20-29.
HEAD, L. 1989. Prehistoric Aboriginal impacts on Australian vegetation: an
assessment of the evidence. Australian Geographer. 20: 21-49.
HEAD, L. 1995. Meganesian barbecue: reply to George Seddon. Meanjin. 54:
702-709.
HECHT, M. 1975. The morphology and relationships of the largest known
terrestrial lizard, Megalania prisca Owen, from the Pleistocene of
Australia. Proceedings of the Royal Society of Victoria. 87: 239-250.
HEDLEY, C. 1924. Some notes on Australian shells. Australian Zoology. 3:
215-222.
HENDY, C.H., RAFTER, T.A. & MACINTOSH, N.W.G. 1971. The formation of
carbonate nodules in the soils of the Darling Downs, Queensland,
Australia, and the dating of the Talgai cranium. Abstracts with Programs.
Geological Society of America. 3: 597-598
HESSE, P.P. MAGEE, J.W. & VAN DER KAARS, S. 2004. Late Quaternary
climates of the Australian arid zone: a review. Quaternary International.
118-119: 87-102.
HOCKNULL, S.A. 2002. Comparative maxillary and dentary morphology of the
Australian dragons (Agamidae: Squamata): A framework for fossil
identification. Memoirs of the Queensland Museum. 48: 125-145.
HOPE, G., KERSHAW, A.P., VAN DER KAARS, S., XIANGJUN, S., LIEW, P.M.,
HEUSSER, L.E., TAKAHARA, H., MCGLONE, M. MIYOSHI, N. & MOSS, P.T.
2004. History of vegetation and habitat change in the Austral-Asian
region. Quaternary International. 118-119: 103-126.
277
HOPE, J.H., LAMPERT, R.J., EDMONSON, E., SMITH, M.J. & VAN TETS, G.F. 1977.
The late Pleistocene faunal remains from Seton Rock Shelter, Kangaroo
Island, South Australia. Journal of Biogeography. 4: 363-385.
HORTON, D.R. 1980. A review of the extinction question: man, climate and
megafauna. Archaeology and Physical Anthropology in Oceania. 17: 86-
97.
HORTON, D.R. 1982. The burning question: Aborigines, fire and Australian
ecosystems. Mankind. 13: 237-251.
HORTON, D.R. 1984. Red kangaroos: last of the Australian megafauna. In:
Martin, P.S. & Klein, R.G. (Eds.), Quaternary Extinctions: A Prehistoric
Revolution, pp. 639-680. The University of Arizona Press. Tuscon.
HORTON, D.R. 2000. The Pure State of Nature. Allen and Unwin, New South
Wales.
HORTON, D.R. & WRIGHT, R.V.S. 1981. Cuts on Lancefield bones: carnivorous
Thylacoleo, not humans, the cause. Archaeology in Oceania. 16. 73-80.
HOUGHTEN, J.T., MEIRA FILHO, L.G., BRUCE, J., HOESUNG, L., CALLANDER, B.A.,
HAITES, E., HARRIS, N. & MASKELL, K. 1995. Climate change 1994.
Radiative Forcing of Climate Change and an Evaluation of the IPCC IS92
Emission Scenarios. Cambridge University Press, Cambridge.
HUBBERTEN, H.W., ANDREEV, A., ASTAKHOV, V.I., DEMIDOV, I., DOWDESWELL,
J.A., HENRIKSEN, M., HJORT, C., HOUMARK-NIELSEN, M., JAKONSSON, M.,
KUZMINA, S., LARSEN, E., LUNKKA, J.P., LYS, A. MACGERUD, J., OLLER, P.M.,
SAARNISTO, M., SCHIRRMEISTER, L., SHER, A., SIEGERT, C., SIEGERT, M.J. &
SVENDSEN, J.I. 2004. The periglacial climate and environment in northern
Eurasia during the Last Glaciation. Quaternary Science Reviews. 23:
1333-1357.
HUTCHINSON, G.E. 1961. The paradox of plankton. The American Naturalist.
95: 137-145.
HUTCHINSON, M.N. 1993. Family Scincidae. In: Glasby, C.J., Ross, G.J.B. &
Beesley, P.L. (Eds.) Fauna of Australia, Amphibia and Reptilia, Vol 2a, pp.
261-279. Australian Publishing Service, Canberra.
HUTTON, F.W. 1884. Revision of the land Mollusca of New Zealand.
Transactions of the New Zealand Institute. XVI: 186-212.
278
HUXLEY, T.H. 1862. On the premolar teeth of Diprotodon and on a new
species of that genus. Quarterly Journal of the Geological Society of
London. 18: 422-427.
ILLIGER, C. 1811. Prodromus systematis mammalium et avium additis
terminus zoographics utriudque classis. C. Salfeld, Berlin, I-xviii, 1-301.
INGRAM, G.J. & LONGMORE, N.W. 1991. The frog records. In: Ingram, G.J. &
Raven, R.J. (Eds.) An Atlas of Queensland’s Frogs, Reptiles, Birds and
Mammals. pp. 16-44. Board of Trustees of the Queensland Museum,
Queensland.
IREDALE, T. 1933. Systematic notes on Australian land shells. Records of the
Australian Museum. 19: 37-59.
IREDALE, T. 1937. A basic list of the land Mollusca of Australia. Australian
Zoologist. 8: 237-333.
JACKSON, S.T. & WENG, C. 1999. Late Quaternary extinction of a tree species
in eastern North America. Proceedings of the National Academy of
Sciences of the United States of America. 96: 13847-13852.
JAMES, H.F., STAFFORD, T.W. JR., STEADMAN, D.W., STEADMAN, D.W., OLSON,
S.L., MARTIN, P.S., JULL, A.J.T. & MCCOY, P.C. 1986. Radiocarbon dates
on bones of extinct birds from Hawaii. Proceedings of the National
Academy of Sciences of the United States of America. 84: 2350-2354.
JAMNICZKY, H. A., BRINKMAN, D. B., RUSSELL, A. P. 2003. Vertebrate microsite
sampling: how much is enough? Journal of Vertebrate Paleoentology 23,:
725-734.
JANSEN, A. & HEALEY, M. 2003. Frog communities and wetland condition:
relationships with grazing by domestic livestock along an Australian
floodplain river. Biological Conservation. 109: 207-219.
JOHNSON, B.J., MILLER, G.H., FOGEL, M.L., MAGEE, J.W., GAGEN, M.K. &
CHIVAS, A.R. 1999. 65,000 years of vegetation change in central Australia
and the Australian summer monsoon. Science. 284: 1150-1152.
JOHNSON, C.N. 2002. Determinants of loss of mammal species during the late
Quaternary ‘megafauna’ extinctions. Life history and ecology, but not body
size. Proceedings of the Royal Society of London, Series B. 269: 2221-
2227.
279
JOHNSON, C.N. 2005a. The remaking of Australia’s ecology. Science. 309:
255-256.
JOHNSON, C.N. 2005b. What can the data on late survival of Australian
megafauna tell us about the cause of their extinction? Quaternary Science
Reviews. 24: 2167-2172.
JOHNSON, C.N. & PRIDEAUX, G.J. 2004. Extinctions of herbivorous mammals
in the late Pleistocene of Australia in relation to their feeding ecology: no
evidence for environmental change as cause of extinction. Austral
Ecology. 29: 553-557.
JOHNSON, C.N. & WROE, S. 2003. Causes of extinction of vertebrates during
the Holocene of mainland Australia: arrival of the dingo, or human impact?
The Holocene. 13: 1009-1016.
JOHNSON, R.G. 1960. Models and methods for analysis of the mode of
formation of fossil assemblages. Geological Society of America, Bulletin.
71: 1075-1088.
JOHNSTON, E. 1989. Human modified bones from early southern Plains Sites.
In: Bonnichsen, R. & Sorg, M.H. (Eds.) Bone Modification, pp. 431-471.
University of Maine Center for the Study of the First Americans, Orono.
JONES, B. & BAYNES, A. 1989. Illustrated keys to Australian Mammalia to
generic level. In: Walton, D.W. & Richardson, B.J. (Eds.) Fauna of
Australia. Mammalia, Vol 1b, pp. 1075-1171. Australian Government
Publishing Service Vol. 1B. Canberra.
JONES, M. 1995. Tasmanian devil. In: Strahan, R. (Ed.) The Mammals of
Australia, pp. 82-84. New Holland Publishers, Sydney, Australia.
JONES, R. 1969. Fire-stick farming. Australian Natural History. 16: 224-228.
KÄLLEN, E., KATTSOV, V., WALSH, J. & WHITEHEAD, E. (Eds.) 2001. Report from
the Arctic Climate Assessment Modeling and Scenarios Workshop.
January 39-31, 2001. Stockholm, Sweden.
KAPPELLE, M., VAN VUUREN, M. & BAAS, P. 1999. Effects of climate change on
biodiversity: a review and identification of key research issues. Biodiversity
and Conservation. 8: 1383-1397.
KEAR, B.P., HAMILTON-BRUCE, R.J., SMITH, B.J. & GOWLETT-HOLMES, K.L.
2003. Reassessment of Australia’s oldest freshwater snail, Viviparus (?)
280
albascopularis Etheridge, 1902 (Mollusca: Gastropoda: Viviparidae), from
the Lower Cretaceous (Aptian, Wallumbilla Formation) of White Cliffs,
New South Wales. Molluscan Research. 23: 149-158.
KEMPER, C. 1990. Status of bandicoots in South Australia. In: Seebeck, J.H.,
Brown, P.R., Wallis R.L., & Kemper C.M. (Eds.). Bandicoots and Bilbies,
pp. 67-72. Surrey Beatty and Sons, Sydney, New South Wales.
KERSHAW, A.P. 1974. A long continuous pollen sequence from north-eastern
Australia. Nature. 251: 221-223.
KERSHAW, A.P. 1978. Record of last interglacial-glacial cycle from
northeastern Queensland. Nature. 271: 159-161.
KERSHAW, A.P. 1986. Climatic change and Aboriginal burning in north-east
Australia during the last two glacial/interglacial cycles. Nature. 322: 47-49.
KERSHAW, A.P. 1994. Pleistocene vegetation of the humid tropics of
northeastern Queensland, Australia. Palaeogeography,
Palaeoclimatology, Palaeoecology. 109: 399-412.
KERSHAW, A.P., MOSS, P. & VAN DER KAARS, S. 2003. Causes and
consequences of long-term climatic variability on the Australian continent.
Freshwater Biology. 48: 1274-1283.
KERSHAW, P., QUILTY, P.G., DAVID, B., VAN HUET, S. & MCMINN, A. 2000.
Palaeobiogeography of the Quaternary of Australia. In: Wright, A.J.,
Young, G.C., Talent, J.A., & Laurie, J.R. (Eds.) Palaeobiogeography of
Australasian Faunas and Floras, pp. 471-515. Memoir of the Association
of Australian Palaeontolgists. 23.
KING, J.E. & SAUNDERS, J.J. 1984. Environmental insularity and the extinction
of the American mastodont. In: Martin, P.S. & Klein, R.G. (Eds.)
Quaternary Extinctions: A Prehistoric revolution, pp. 315-344. University of
Arizona Press, Tucson.
KIRSCH, J.A.W. 1968. Prodromus of the comparative serology of Marsupialia.
Nature. 217: 418-420.
KLAATSCH, H. 1904. Übersicht über den bischerigen Verlauf und die
Errungenschaften seiner Reise in Australien bis Ende September 1904.
Zeitschrift für Ethnologies. 1904: 211-213.
281
KLEIN, R. G. 1975. Middle Stone Age man-animal relationships in South
Africa: evidence from Die Kelders and Klasies River Mouth. Science. 190:
265-267.
KLEIN, R.G. 1982. Age (mortality) profiles a means of distinguishing hunted
species from scavenged ones in Stone Age archaeological sites.
Palaeobiology. 8: 151-158.
KOHEN, J. 1995. Aboriginal Environmental Impact. University of New South
Wales Press, Sydney.
KORTH, W.W. 1979. Taphonomy of microvertebrate fossil assemblages.
Annals of the Carnegie Museum. 48: 235-285.
KOS, A.M. 2003a. Pre-burial taphonomic characterisation of a vertebrate
assemblage from a pitfall cave fossil deposit in southeastern Australia.
Journal of Archaeological Science. 30: 769-779.
KOS, A.M. 2003b. Characterisation of post-depositional taphonomic
processes in the accumulation of mammals in a pitfall cave deposit from
southeastern Australia. Journal of Archaeological Science. 30: 781-796.
KUZMIN, Y.V. & ORLOVA, L.A. 2004. Radiocarbon chronology and environment
of woolly mammoth (Mammuthus primigenius Blum.) in northern Asia:
results and perspectives. Earth-Science Reviews. 68: 133-169.
LACOURSE, T., MATHEWES, R.W. & FEDJE, D.W. 2005. Late-glacial vegetation
dynamics of the Queen Charlotte Islands and adjacent continental shelf,
British Columbia, Canada. Palaeogeography, Palaeoclimatology,
Palaeoecology. 226: 36– 57.
LAMB, J. 1911. Description of three new batrachians from southern
Queensland. Annals of the Queensland Museum. 10: 26-28.
LAMBECK, K. & CHAPPELL, J. 2001. Sea level change through the last glacial
cycle. Science. 292: 679-686.
LAMPRELL, K. & HEALY, J. 1998. Bivalves of Australia. Backhuys Publishers,
Leiden. Netherlands.
LAUCK, B. & TYLER, M.J. 1999. Ilial shaft curvature: a novel osteological
feature distinguishing two closely related species of Australian frogs.
Transactions of the Royal Society of South Australia. 123: 151-152.
LAURENTI, J.N. 1768(1966). Specimen medicum, exhibens synopsin
Reptilium. A. Asher & Co. Amsterdam. VIII.
282
LAVERY, H. J. & GRIMES, R. J. 1974. Mammals and birds of the Ingham
district, north Queensland. I. Introduction and mammals. Queensland
Journal of Agricultural and Animal Sciences. 31: 383-90.
LAWSON, E.M, ELLIOT, G., FALLON, J., FINK, D., HOTCHKIS, M.A.C., HUA, Q.,
JACOBSEN, G.E., LEE, P., SMITH, A.M., TUNIZ, C. & ZOPPI, U. 2000. AMS at
ANTARES- The first 10 years. Nuclear Instruments and Methods in
Physics Research Section B: Beam Interactions with Materials and Atoms.
172: 95-99.
LEICHHARDT, F.W.L. 1843. Journal (28/12/1842 – 24/07/1843). Handwritten
manuscripts in the Mitchell Library, Sydney.
LEYDEN, B.W. 1984. Guatemalan forest synthesis after Pleistocene aridity.
Proceedings of the National Academy of Sciences of the United States of
America. 81: 4856-4859.
LINNAEUS, C. 1758. Systema Naturae per regna tria naturae, secundum
classes, ordines, genera, species, cum characteribus, differentiis,
synonymis, locis. Holmiae: Laurentii Salvii Vol. Tom. 1 10th Edition.
LISTER, A.M. 2004. The impact of Quaternary ice ages on mammalian
evolution. Philosophical Transactions: Biological Sciences. 359: 221-241.
LOFGREN, D.L., HOTTON, C.L. & RUNKEL, A.C. 1990. Reworking of Cretaceous
dinosaurs into Paleocene channel deposits, upper Hell Creek Formation,
Montana. Geology. 18: 874-877.
LONG, J., ARCHER, M. FLANNERY, T. & HAND, S. 2002. Prehistoric Mammals of
Australia & New Guinea: One Hundred Years of Evolution. John Hopkins
University Press. Baltimore.
LONG, J. & MACKNESS, B. 1994. Studies of the late Cainozoic diprotodontid
marsupials of Australia. 4. The Bacchus Marsh diprotodons- Geology,
sedimentology and taphonomy. Records of the South Australia Museum.
27: 95-110.
LONGMAN, H.A. 1916. The supposed artiodactyle Queensland fossils.
Proceedings of the Royal Society of Queensland. 28: 83-87.
LONGMAN, H.A. 1924. Some Queensland fossil vertebrates. Memoirs of the
Queensland Museum. 7: 16-25.
LONGMAN, H.A. 1936. Fossilised vertebrae of large teleost fish from tunnel
under Davies Park, S. Brisbane, cf. a groper, coll. Mr. John Struby; fossil
283
femur of rodent from King’s Creek, Darling Downs, coll. Mr. R. Frost.
Proceedings of the Royal Society of Queensland, 47, Abstract, 23rd April
1935, p. vii.
LONGMORE, M.E. & HEIJNIS, H. 1999. Aridity in Australia: Pleistocene records
of palaeohydrological and palaeoecological change from the perched lake
sediments of Fraser Island, Queensland, Australia. Quaternary
International. 57/58: 35-47.
LOWRY, B. 2005. Marching after the megafauna. Queensland Naturalist. 43:
24-32.
LUCKETT, W.P. 1993. An ontogenetic assessment of dental homologies in
therian mammals. In: Szalay, F.S., Novacek, M.J. & McKenna, M.C. (Eds.)
Mammal Phylogeny, Volume 1, pp. 182-204. Springer-Verlag, New York.
LUDBROOK, N.H. 1978. Quaternary molluscs of the western part of the Eucla
Basin. Bulletin of the Geological Survey of Western Australia. 125: 1-286.
LUDBROOK, N.H. 1984. Quaternary molluscs of South Australia. Department
of South Australia. Department of Mines and Energy, South Australia.
Handbook no. 9.
LULY, J.G. 2001. On the equivocal fate of Late Pleistocene Callitris Vent.
(Cupressaceae) woodlands in arid South Australia. 83-85: 155-168.
LUNDELIUS, E.L. JR. 1983. Climatic implications of late Pleistocene and
Holocene faunal associations in Australia. Alcheringa. 7: 125-149.
LUNDELIUS, E.L. JR. 1989. The implications of disharmonious assemblages
for Pleistocene extinctions. Journal of Archaeological Science. 16: 407-
417.
LYDEKKER, R. 1888. Catalogue of fossil reptilia and amphibia in the British
Museum (Natural History). Part 1.
LYMAN, R.L. 1994. Vertebrate Taphonomy. Cambridge University Press
Cambridge.
LYMAN, R.L. & FOX, G.L. 1989. A critical evaluation of bone weathering as an
indication of bone assemblage formation. Journal of archaeological
Science. 14: 293-317.
LYNCH, J.D. 1971. Evolutionary relationships, osteology, and zoogeography
of leptodactyloid frogs. Miscellaneous Publications of the Museum of
Natural History, University of Kansas. 53: 1-238.
284
LYNE, A.G. & MORT, P.A. 1981. A comparison of skull morphology in the
marsupial bandicoot genus Isoodon: its taxonomic implications and notes
on new species, Isoodon arnhemensis. Australia Mammalogy. 4: 107-133.
LYONS, S.K. 2003. A quantitative assessment of the range shifts of
Pleistocene mammals. Journal of Mammalogy. 84: 385-402.
LYONS, S.K., SMITH, F.A. & BROWN, J.H. 2004a. Of mice, mastodons and
men: human-mediated extinctions on four continents. Evolutionary
Ecology Research. 6: 339-358.
LYONS, S.K., SMITH, F.A., WAGNER, P.J., WHITE, E.P. & BROWN, J.H. 2004b.
Was ‘hyperdisease’ responsible for the late Pleistocene megafaunal
extinction? Ecology Letters. 7: 859-868.
MACARTHUR, R.H. 1957. On the relative abundance of bird species.
Proceedings of the National Academy of Sciences of the United States of
America. 43: 293-295.
MACARTHUR, R. 1960. On the relative abundance of species. American
Naturalist. 94: 25-36.
MACINTOSH, N.W.G. 1967. Fossil man in Australia. Australian Journal of
Science. 30: 86-98.
MACKENZIE, N.L., BURBIDGE, A.A., 1979. The wildlife of some existing and
proposed nature reserves in the Gibson, Little Sandy and Great Victoria
Deserts, Western Australia. Wildlife Research Bulletin of Western
Australia 8: 1-36.
MACKNESS, B. 1995. Palorchestes selestiae, a new species of palorchestid
marsupial from the early Pliocene Bluff Downs Local Fauna, northeastern
Queensland. Memoirs of the Queensland Museum. 38: 603-609.
MACKNESS, B.S. & GODTHELP, H. 2001. The use of Diprotodon as a
biostratigraphic marker of the Pleistocene. Transactions of the Royal
Society of South Australia. 125: 155-156.
MACKNESS, B.S., WROE, S., MUIRHEAD, J. WILKINSON, C.E. & WILKINSON, D.M.
2000. First fossil bandicoot from the Pliocene Chinchilla Local Fauna.
Australian Mammalogy. 22: 133-136.
MACPHEE, R.D.E. & MARX, P.A. 1997. Humans, hyperdisease, and first-
contact extinctions. In: Goodman, S.M. & Patterson, B.D. (Eds.) Natural
285
Change and Human Impact in Madagascar, pp. 169-217. Smithsonian
Institute Press, Washington DC.
MACPHEE, R.D.E., TIKHONOV, A.N., MOL, D., DE MARLIAVE, C., VAN DER PLICHT,
H., GREENWOOD, A.D., FLEMMING, C. & AGENBROAD, L. 2002. Radiocarbon
chronologies and extinction dynamics of late Quaternary mammalian
megafauna from the Taimyr Peninsula, Russian Federation. Journal of
Archaeological Science. 29: 1017-1042.
MALLICK, R. & FRANK, N. 2002. A new technique for precise uranium-series
dating of travertine micro-samples. Geochimica et Cosmochimica Acta.
66: 4261-4272.
MARSHALL, L.G. 1989. Bone modification and “the laws of burial”. In:
Bonnichsen, R. & Sorg, M.H. (Eds.) Bone Modification, pp. 7-24. Center
for the Study of the First Americans, University of Maine, Orono.
MARSHALL, L.G. & CURRUCINI, R. 1978. Variability, evolutionary rates and
allometry in dwarfing lineages. Paleobiology. 4: 101-119.
MARTILL, D.M. 1985. The preservation of marine vertebrates in the Lower
Oxford Clay (Jurassic) of central England. In: Whittington, H.B. & Conway
Morris, S. (Eds.) Extraordinary Fossil Biotas: Their Ecological and
Evolutionary Significance, pp. 155-165. Philosophical Transactions of the
Royal Society of London (B), London.
MARTILL, D.M. 1987. A taphonomic and diagenetic case study of a partially
articulated ichthyosaur. Palaeontology. 30: 543-555.
MARTIN, P.S. 1963. The Last 10,000 years: A Fossil Pollen Record of the
American Southwest. University of Arizona Press. Tucson.
MARTIN, P.S. 1984. Prehistoric overkill: the glacial model. In: Martin, P.S. &
Klein, R.G. (Eds.) Quaternary Extinctions: A Prehistoric Revolution, pp.
354-403. University of Arizona Press, Tucson.
MARTIN, P.S. & KLEIN, R.G. (Eds.) 1984. Quaternary Extinctions: A Prehistoric
Revolution. University of Arizona Press, Tucson. 892 pp
MARTIN, R.E. 1999. Taphonomy: A Process Approach. University Press,
Cambridge, United Kingdom.
MARTIN-KAYE, P. 1951. Sorting of lamellibranch valves on beaches in
Trinidad, B.W.L. Geological Magazine. 88: 432-434.
286
MARSHALL, L.G. & CORRUCCINI, R.S. 1978. Variability, evolutionary rates, and
allometry in dwarfing lineages. Paleobiology. 4: 101-119.
MCDONALD, H.G. & PELIKAN, S. 2006. Mammoths and mylodonts: exotic
species from two different continents in North American Pleistocene
faunas. Quaternary International. 142-143: 229-241.
MCDONALD, J.N. 1984. The reordered North Americas selection regime and
late Quaternary megafaunal extinction. In Martin, P.S. & Klein, R.G. (Eds.)
Quaternary Extinctions: A Prehistoric Revolution, pp. 404-439. University
of Arizona Press, Tucson.
MCDOWELL, M.C. 1997. Taphonomy and palaeoenvironmental interpretation
of a late Holocene deposit from Black’s Point Sinkhole, Venus Bay, S.A.
Proceedings of the Linnean Society of New South Wales. 117: 79-96.
MCFARLAND, D. HASELER, M., VENZ, M., REIS, T., FORD, G., HINES, B. 1999.
Terrestrial Vertebrate Fauna of the Brigalow Belt South Bioregion:
Assessment and Analysis for Conservation Planning. Queensland
Environmental Protection Agency. Brisbane, Queensland.
MCMICHAEL, D.F. 1968. Non-marine Mollusca from Tertiary rocks in northern
Australia. Bulletin of the Bureau of Mineral Resources, Geology and
Geophysics, Australia. 80: 133-157.
MCNEIL, P., HILLS, L.V., KOOYMAN, B. & TOLMAN, S.M. 2005. Mammoth tracks
indicate a declining Late Pleistocene population in southwestern Alberta,
Canada. Quaternary Science Reviews. 24: 1253-1259.
MEGIRIAN, D. 1992. Approaches to marsupial biochronology in Australia and
New Guinea. Alcheringa. 18: 259-274.
MELTZER, D.J. & MEAD, J.I. 1985. Dating late Pleistocene extinction:
theoretical issues, analytical bias, and substantive results. In: Mead, J.I. &
Melzer, D.J. (Eds.) Environments and Extinctions: Man in Late Glacial
North America, pp. 145-173. Center for the Study of Early Man, Orono,
Maine.
MENKHORST, P. W. & SEEBECK, J. H. 1990. Distribution and conservation
status of bandicoots in Victoria. In: Seebeck, J.H., Brown, P.R., Wallis
R.L. & Kemper C.M. (Eds.) Bandicoots and Bilbies, pp. 51-60. Surrey
Beatty and Sons, Sydney, New South Wales.
287
MERREM, B. 1820. Versuch eines Sytems Amphibien. Tentamen systematis
Amphibiorum. Krieger, Marburg.
MERRILEES, D. 1965. Fossil bandicoots (Marsupialia, Peramelidae) from
Mammoth Cave, Western Australia, and their climatic implications. Journal
of the Royal Society of Western Australia. 50: 121-128.
MIALL, A.D. 1996. The Geology of Fluvial Deposits: Sedimentary Facies,
Basin Analysis and Petroleum Geology. Springer-Verlag Incorportated,
Berlin.
MILANKOVITCH, M. 1941. Canon of insolation and the ice-age problem. Royal
Serbian Academy. Special Publication No. 32, translated from German by
Israel Program for Scientific Translations, Jerusalem, 1969.
MILLARD, A.R. & HEDGES, R.E.M. 1996. A diffusion-absorption model of
uranium uptake by archaeological bone. Geochimica et Cosmochimica
Acta. 60: 2139-2152.
MILLER, G.H., FOGEL, M.L., MAGEE, J.W., GAGAN, M.K., CLARKE, S.J. &
JOHNSON B.J. 2005a. Ecosystem collapse in Pleistocene Australia and a
human role in megafaunal extinction. Science. 309: 287-290.
MILLER, G.H., MAGEE, J.W., JOHNSON, B.J., FOGEL, M.L., SPOONER, N.A.,
MCCULLOCH, M.T. & AYLIFFE, L.K. 1999. Pleistocene extinction of
Genyornis newtoni: human impact on Australian megafauna. Science.
283: 205-208.
MILLER, G.H., MANGAN, J., POLLARD, D., THOMPSON, S.L., FELZER, B.S., &
MAGEE, J.W. 2005b. Sensitivity of the Australian Monsoon to insolation
and vegetation: Implications for human impact on continental moisture
balance. Geology. 33: 65-68.
MOLNAR, R.E. 1990. New cranial elements of a giant varanid from
Queensland. Memoirs of the Queensland Museum. 29: 437-444.
MOLNAR, R.E. & KURZ, C. 1997. The distribution of Pleistocene vertebrate on
the eastern Darling Downs, based on the Queensland Museum
collections. Proceedings of the Linnean Society of New South Wales. 117:
107-134.
MOLNAR, R.E., WILKINSON, J. & SOBBE, I.H. 1999. Pleistocene fauna and
taphonomy at Ned’s Gully, eastern Darling Downs, Queensland. Abstracts
288
of the 6th CAVEPS, July, 1997. Records of the Western Australian
Museum. Supplement 57: 412.
MOORE, J.A., 1958. A genus and species of leptodactylid frog from Australia.
American Museum Novitates. 1919: 1-7.
MORIARTY, K.C., MCCULLOCH, M.T., WELLS, R.T. & MCDOWELL, M.C. 2000.
Mid-Pleistocene cave fills, megafaunal remains and climate change at
Naracoorte, South Australia: towards a predictive model using U-Th dating
of speleothems. Palaeogeography, Palaeoclimatology, Palaeoecology.
159: 113-143.
MORWOOD, M., SOEJONO, R.P., ROBERTS, R.G., SUTIKNA, T., TURNEY, C.S.M.
WESTAWAY, K.E., RINK, W.J., ZHAO, J-X., VAN DEN BERGH, G.D., ROKUS AWE
DUE, HOBBS, D.R., MOORE, M.W., BIRD, M.A. & FIFIELD, L.K. 2004.
Archaeology and age of a new hominin from Flores in eastern Indonesia.
Nature. 431: 1087-1091.
MOYLE, P.B. & RANDALL, P.J. 1998. Evaluating the biotic integrity of
watersheds in the Sierra Nevada, California. Conservation Biology. 12:
1318-1326.
MUIRHEAD, J. 1994. Systematicd, evolution and palaeobiology of recent and
fossil bandicoots (Marsupialia: Peramelemorphia). Unpublished PhD.
dissertation, University of New South Wales, Sydney.
MUIRHEAD, J., DAWSON, L. & ARCHER, M. 1997. Perameles bowensis, a new
species of Perameles (Peramelemorphia, Marsupialia) from Pliocene
faunas of Bow and Wellington Caves, New South Wales. Proceedings of
the Linnean Society of New South Wales. 117: 163-173.
MUIRHEAD, J. & FILAN, S.L. 1995. Yarala burchfieldi, a plesiomorphic
bandicoot (Marsupialia, Peramelemorphia) from Oligo-Miocene deposits
of Riversleigh, northwestern Queensland. Journal of Paleontology. 69:
127-134.
MÜLLER, J. 1846. On the structure and characters of the ganoidei, and the
natural classification of fish. Scientific Memoirs. 4: 499-552.
MULVANEY, D.J. & KAMMINGA, J. 1999. Prehistory of Australia. Allen and
Unwin. Sydney.
289
MURRAY, P.F. 1984. Extinctions downunder: a bestiary of extinct Australian
late Pleistocene monotremes and marsupials. In: Martin, P.S. & Klein,
R.G. (Eds.) Quaternary Extinctions: A Prehistoric Revolution, pp. 600-628.
University of Arizona Press, Tucson.
MURRAY, P.F. 1991. The Pleistocene megafauna of Australia. In: Vicker-Rich,
P., Monaghan, J.M., Baird, R.F. & Rich, R.F. (Eds.) Vertebrate
Paleontology of Australasia, pp. 1071-1164. Pioneer Design Studios,
Lilydale, Victoria.
MURRAY, P.F. 1998. Palaeontology and palaeobiology of wombats. In: Wells,
R.T. & Pridmore, P.A. (Eds.) Wombats, pp. 1-33. Surrey Beatty & Sons,
Chipping North.
NAGLE, J.S. 1967. Wave and current orientation of shells. Journal of
Sedimentary Petrology. 37: 1124-1138.
NAMI, H.G. 1996. New assessments of early human occupations in the
Southern Cone. In: Akazawa, T. & Szathmáry (Eds.) Prehistoric
Mongoloid Dispersals, pp. 256-269. Oxford University Press, Oxford.
NANSON, G.C., PRICE, D.M. & SHORT, S.A. 1992. Wetting and drying of
Australia over the past 300 ka. Geology. 20: 791-794.
NICHOLSON, P.H. 1981. Fire and the Australian Aborigine- an enigma. In: Gill,
A.M., Groves, R.H. & Noble, I.R. (Eds.) Fire and the Australian Biota, pp.
55-76. Australian Academy of Science, Canberra.
O’CONNELL, J.F. & ALLEN, J. 2004. Dating the colonisation of Sahul
(Pleistocene Australia-New Guinea): a review of recent research. Journal
of Archaeological Science. 31: 835-853.
OWEN, R. 1838. Fossil mammal remains from Wellington Valley, Australia.
Marsupialia. Pp. 359-369, Appendix to Mitchell, T. L. Three expeditions
into the interior of eastern Australia, with descriptions of the recently
explored region of Australia Felix, and of the present colony of New South
Wales. T. and W. Boone, London. 2.
OWEN, R. 1858. Odontology. Teeth of Mammals. Encyclopedia Brittannica,
or dictionary of arts, sciences, and general literature, 8th edition.
OWEN, R. 1860. Description of some remains of a gigantic land-lizard
(Megalania prisca) from Australia. Philosophical Transactions of the Royal
Society. 1860: 45-46.
290
OWEN, R. 1874. On the fossil mammals of Australia, part VIII. Family
Macropodidae: genera Macropus, Osphranter, Phascolagus, Sthenurus
and Protemnodon. Philosophical Transactions of the Royal Society. 164:
245-287.
OWEN, R. 1877a. Researches on the fossil remains of the extinct mammals
of Australia; with a notice of the extinct mammals of England. J. Erxleben,
England.
OWEN, R. 1877b. On a new species of Sthenurus, with remarks on the
relation of the genus to Dorcopsis, Müller. Proceedings of the Scientific
Meetings of the Zoological Society of London. 1877: 352-361.
OWEN-SMITH, N. 1987. Pleistocene extinctions: the pivotal role of
megaherbivores. Paleobiology. 13: 351-362.
OWEN-SMITH, R.N. 1988. Megaherbivores: The Influence of Very Large Body
Size on Ecology. Cambridge University Press. Cambridge.
PACK, S.M., MILLER, G.H., FOGEL, M.L. & SPOONER, N.A. 2003. Carbon
isotopic evidence for increased aridity in northwestern Australia through
the Quaternary. Quaternary Science Reviews. 22: 629-643.
PAHNKA, K., ZAHN, R., ELDERFIELD, H. & SCHULTZ, M. 2003. 340,000-year
centennial-scale marine record of Southern Hemisphere climatic
oscillation. Science. 301: 948-952.
PAILLARD, D. 2001. Glacial cycles: towards a new paradigm. Reviews of
Geophysics. 39: 325-346.
PARKER, H.W. 1940. The Australasian frogs of the family Leptodactylidae.
Novitates Zoologicae. 42: 1-106.
PAYNE, J. L. 2003. Applicability and resolving power of statistical tests for
simultaneous extinction events in the fossil record. Paleobiology. 29: 37-
51.
PETERS, W. 1863. Übersicht der von Hrn. Richard Schomburgkan das
zoologishe museum eingesandten Amphibien, aus Buchstelde bei
Adelaide in Südaustralien. Monatsberichte der königlichen preussichen
Akademie der Wissenshaften zu Berlin.
PETIT, J.R., JOUZEL, J., RAYNAUD, R., BARKOV, N.I., BARNOLA, J.-M., BASILE, I.,
BENDER, M., CHAPPELLAZ, J., DAVIS, M., DELAYGUE, G., DELMOTTE, M.,
291
KOTLYAKOV, V.M., LEGRAND, M., LIPENKOV, V.Y., LORIUS C., PÉPIN, L., RITZ,
C., SALTZMAN, E. & STIEVENARD, M. 1999. Climate and atmospheric history
of the past 420,000 years from the Vostok ice core, Antarctica. Nature.
399: 429-436.
PFEIFFER, L. 1845. Descriptions of twenty-two new species of Helix, from the
collections of Miss Saul, Mr Walton Esq., and H. Cuming, Esq.
Proceedings of the Zoological Society of London. 1845: 71-75.
PHILIPPI, R.A. 1847. Abbildungen und Beschriebungen neuer oder wenig
gekannter Conchylien. Cassel. Theodor Fischer. 3: 1-50.
PHOENIX, G.K. & LEE, J.A. 2004. Predicting impacts of Arctic climate changes:
past lessons and future challenges. Ecological Research. 19: 65-74.
PIANKA, E. R. & SCHALL, J. J. 1981. Species densities of Australian
vertebrates. In: Keast, A. (Ed.) Ecological Biogeography of Australia, pp.
1676-1694. Dr. W. Junk Publishers. The Hague, The Netherlands.
PIKE, A.W.G., HEDGES, R.E.M., VAN CALSTEREN, P. 2002. U-series dating of
bone using the diffusion-adsorption model. Geochimica et Cosmochimica
Acta. 66: 4273-4286.
PILSBRY, H.A. 1895. In: Tryon, G.W. & Pilsbry, H.A. (Eds.) Manual of
Conchology. Conchological Section, Academy of Natural Sciences,
Philadelphia. Series 2. 8.
PLEDGE, N.S. 1990. The Upper Fossil Fauna of the Henschke Fossil Cave,
Naracoorte, South Australia. Memoirs of the Queensland Museum. 28:
247-262.
POOLE, W.E. 1995. Eastern grey kangaroo. In: Strahan, R. (Ed.) The
Mammals of Australia, pp. 335-338. New Holland Publishers, Sydney,
Australia.
PRICE, C. & RIND, D. 1994. Possible implications of global warming on global
lightning distributions and frequencies. Journal of Geophysical Research.
104: 1943-1956.
PRICE, G.J. 2002. Perameles sobbei, sp. nov. (Marsupialia, Peramelidae), a
Pleistocene bandicoot from the Darling Downs, south-eastern
Queensland. Memoirs of the Queensland Museum. 48: 193-197.
PRICE, G.J. 2003. Pleistocene palaeoecology of the eastern Darling Downs:
Site QML796. Conference on Australian Vertebrate Evolution,
292
Palaeontology, and Systematics, Queensland Musuem, Brisbane, July 7-
11th 2003. Abstracts. 6-7.
PRICE, G.J. 2005 (2004). Fossil bandicoots (Marsupialia, Peramelidae) and
environmental change during the Pleistocene on the Darling Downs,
southeastern Queensland, Australia. Journal of Systematic Palaeontology.
4: 347-356.
PRICE, G.J. & HOCKNULL, S.A. 2005. A small adult Palorchestes (Marsupialia,
Palorchestidae) from the Pleistocene of the Darling Downs, southeast
Queensland. Memoirs of the Queensland Museum 51: 202.
PRICE, G.J. & SOBBE, I.H. 2003. The palaeoecology of Frog Hollow
(QML1396), King Creek, Darling Downs. Conference on Australian
Vertebrate Evolution, Palaeontology, and Systematics, Queensland
Museum, Brisbane, July 7-11th 2003. Abstracts. 8-9.
PRICE, G.J. & SOBBE, I.H. 2005. Pleistocene Palaeoecology and
environmental change on the Darling Downs, southeastern Queensland,
Australia. Memoirs of the Queensland Museum. 51: 171-201.
PRICE, G.J., TYLER, M.J. & COOKE, B.N. 2005. Pleistocene frogs from the
Darling Downs, southeastern Queensland, Australia, and their
palaeoenvironmental significance. Alcheringa. 29: 171-182.
PRICE, G.J. & WEBB, G.E. in press. Late Pleistocene sedimentology,
taphonomy and megafauna extinction on the Darling Downs, southeastern
Queensland, Australia. Australian Journal of Earth Sciences.
PRIDEAUX, G.J. 2004. Systematics and Evolution of the Sthenurine
Kangaroos. University of California Publications. University of California
Press, London, England. 146.
QUOY, J.R.C. & GAIMARD, J.P. 1824. Zoologie. In: Freycinet, L.C. de (Ed.)
Voyage Autour Du Monde, p. 56. Pillet Ainé, Imprimeur-Libraire, Paris.
RAFINESQUE, C.S. 1815. Analyse de la Nature, ou Tableau de l'Univers et des
Corps Organises. Palermo.
RAPSON, D.J. 1990. Pattern and process in intra-site spatial analysis: site
structural and faunal research at the Bugas-Holding Site. Ph.D.
dissertation, University of New Mexico, Albuquerque. Ann Arbor.
University Microfilms International.
293
REED, E.H. 2003. Vertebrate Taphonomy of Large Mammal Bone Deposits,
Naracoorte Caves World Heritage Area. Unpublished PhD thesis, Flinders
University of South Australia.
REED, E.H. & BOURNE, S.J. 2000. Pleistocene fossil vertebrate sites of the
South East region of South Australia. Transactions of the Royal Society of
South Australia. 124: 61-90.
REID, J.R.W., KERLE, J.A., MORTON, S.R., 1993. Uluru Fauna: The Distribution
and Abundance of Vertebrate Fauna of Uluru (Ayers Rock-Mount Olga)
National Park. Australian National Parks and Wildlife Service. Canberra.
RIDE, W.D.L. 1964. A review of Australian fossil marsupials. Journal of the
Royal Society of Western Australia. 47: 97-131.
RIDE, W.D.L. & DAVIS, A.C. 1997. Origins and setting: mammal Quaternary
palaeontology in the Eastern Highlands of New South Wales. 117: 197-
222.
ROBERTS, J.D. & MAXSON, L.R. 1986. Phylogenetic relationships in the genus
Limnodynastes (Anura: Myobatrachidae): a molecular perspective.
Australian Journal of Zoology. 34: 561-573.
ROBERTS, R.G., FLANNERY, T.F., AYLIFFE, L.K., YOSHIDA, H., OLLEY, J.M.,
PRIDEAUX, G.J., LASLETT, G.M., BAYNES, A., SMITH, M.A., JONES, R. & SMITH,
B.L. 2001a. New ages for the last Australian megafauna: continent-wide
extinction about 46,000 years ago. Science. 292: 1888-1892.
ROBERTS, R.G., FLANNERY, T.F., AYLIFFE, L.K., YOSHIDA, H., OLLEY, J.M.,
PRIDEAUX, G.J., LASLETT, G.M., BAYNES, A., SMITH, M.A., JONES, R. & SMITH,
B.L. 2001b. Archaeology and Australian megafauna. Response. Science.
294: 7a.
ROBERTS, R.G., FLANNERY, T.F., AYLIFFE, L.K., YOSHIDA, H., OLLEY, J.M.,
PRIDEAUX, G.J., LASLETT, G.M., BAYNES, A., SMITH, M.A., JONES, R. & SMITH,
B.L. 2001c. The last Australian megafauna. Australasian Science 22(9):
40-41.
ROBERTS, R.G. & JONES, R. 1994. Luminescence dating of sediments: new
light on the human colonisation of Australia. Australian Aboriginal Studies.
2: 2-17.
ROBERTS, R. G., JONES, R., SPOONER, N. A., HEAD, M. J., MURRAY, A. S. &
SMITH, M. A. 1994. The human colonisation of Australia: Optical dates of
294
53,000 and 60,000 years bracket human arrival at Deaf Adder Gorge,
Northern Territory. Quaternary Science Reviews. 13: 575-583.
ROFF, D.A. 1994. The evolution of flightlessness: is history important?
Evolutionary Ecology. 8: 639-657.
ROOT, T.L., MACMYNOWSKI, D.P., MASTRANDREA, M.D. & SCHNEIDER, S.H.
2005. Human-modified temperatures induce species changes: joint
attribution. Proceedings of the National Academy of Sciences of the
United States of America. 102: 7465-7469.
ROSE, K.D. 1981. The Clarforkian land-mammal age and mammalian faunal
composition across the Paleocene-Eocene boundary. University of
Michigan Papers on Paleontology. 26: v-189.
ROSENZWEIG, M. 2001. Loss of speciation rate will impoverish future diversity.
Proceedings of the National Academy of Sciences of the United States of
America. 98: 5404-5410.
ROUNSEVELL, D.E. & MOONEY, N. 1995. Thylacine. In: Strahan, R. (Ed.) The
Mammals of Australia, pp. 164-165. New Holland Publishers, Sydney,
Australia.
SCHEFFER, M., Carpenter, S., Foley, J.A., Folke, C. & Walker, B. 2001.
Catastrophic shifts in ecosystems. Nature. 413. 591-596.
SCHLEGEL, H. 1850. Description of a new genus of batrachians from Swann
River. Proceedings of the Zoological Society of London. 18: 9-10.
SEMKEN, H.A. 1974. Micromammal distribution and migration during the
Holocene. Abstracts of the 3rd Annual Meeting of the American
Quaternary Association. 25.
�EKERCIO�LU, Ç.H., DAILY, G.C. & EHRLICH, P.R. 2004. Ecosystem
consequences of bird declines. Proceedings of the National Academy of
Sciences of the United States of America. 101: 18042-18047.
SHAPIRO, B., DRUMMOND, A.J., RAMBAUT, A., WILSON, M.C., MATHEUS, P.E.,
SHER, A.V., PYBUS, O.G., GILBERT, M.T.P., BARNES, I., BINLADEN, J.,
WILLERSLEV, E., HANSEN, A.J., BARYSHNIKOV, G.F., BURNS, J.A., DAVYDOV,
S., DRIVER, J.C., FROESE, D.G., HARRINGTON, C.R., KEDDIE, G., KOSINTSEV,
P., KUNZ, M.L., MARTIN, L.D., STEPHENSON, R.O., STORER, J., TEDFORD, R.,
ZIMOV, S. & COOPER, A. 2004. Rise and fall of the Beringian Steppe Bison.
Science. 306: 1561-1565.
295
SHARPTON, V.L. & WARD, P.D. (Eds.) 1990. Global Catastrophes in Earth
History: The Proceedings of an Interdisciplinary Conference on Impacts,
Volcanism and Mass Mortality. Geological Society of America Special
Paper 247.
SHAW, G. 1797. The Naturalist’s Miscellany: or coloured figures of natural
objects, drawn and described immediately from nature. E. Nodder,
London. Volume 8.
SHAW, B. 1799. The Naturalist’s Miscellany: or coloured figures of natural
objects, drawn and described immediately from nature. Nodder and Co.
London. Volume 10(18).
SHELDON, F. & WALKER, K.F. 1989. Effects of hypoxia on oxygen consumption
by two species of freshwater mussel (Unionacea: Hyriidae) from the River
Murray (Australia). Australian Journal of Marine and Freshwater
Research. 40: 491-500.
SHIMOYAMA, S., & HAMANO, T. 1990. The effect of oxygen-deficient water for
the molluscan thanatocoenosis in Hakata Bay. In: Robba, E. (Ed.)
Proceedings of the Fourth Symposium on Ecology and Paleontology of
Benthic Communities, Sorrento, 1-5 November, 1988, pp. 753-772.
Museo Regionale di Scienze Natural di Trino, Trino.
SHIMOYAMA, S. & FUJISAKA, H. 1992. A new interpretation of the left-right
phenomenon during spatial diffusion and transport of bivalve shells.
Journal of Geology. 100: 291-304.
SHIPMAN, P. 1981. Life History of a Fossil: An Introduction to Taphonomy and
Paleoecology. Harvard University Press, Cambridge.
SHUMAN, B., NEWBY, P., HUANG, Y. & WEBB, T. III. 2004. Evidence for the
close climatic control of New England vegetation history. Ecology. 85:
1297-1310.
SIGNOR, P. W., III, & LIPPS, J. H. 1982. Sampling bias, gradual extinction
patterns and catastrophes in the fossil record. Geological Society of
America Special Papers. 190: 291-296.
SIMPSON, J.J. & GRÜN, R. 1998. Non-destructive gamma spectrometric U-
series dating. Quaternary Geochronology. 19: 1009-1022.
296
SINCLAIR, A.R.E. 2003. Mammal population regulation, keystone processes
and ecosystem dynamics. Philosophical Transactions: Biological
Sciences. 358: 1729-1740.
SINGH, G. & GEISSLER, E.A. 1985. Late Cainozoic history of vegetation, fire,
lake levels and climate at Lake George, New South Wales, Australia.
Philosophical Transactions of the Royal Society of London. 31: 379-447.
SIMPSON, J.J. & GRÜN, R. 1998. Non-destructive gamma spectrometric U-
series dating. Quaternary Geochronology. 17: 1009-1022.
SINCLAIR, A.R.E. 2003. Mammal population regulation, keystone processes
and ecosystem dynamics. Philosophical Transactions: Biological
Sciences. 358: 1729-1740.
SMITH, B.J. & KERSHAW, R.C. 1979. Field Guide to the Non-marine Molluscs
of South-Eastern Australia. A.N.U. Press, Canberra.
SMITH, F.A., LYONS, S.K., ERNEST, S.K.E., JONES, K.E., KAUFFMAN, D.M.,
DAYAN, T., MARQUET, P.A., BROWN, J.H. & HASKELL, J.P. 2003. Body mass
of late Quaternary mammals. Ecology. 84: 3403.
SMITH, M.J. 1972. Small fossil vertebrates from Victoria Cave, Naracoorte,
South Australia. II. Peramelidae, Thylacindae and Dasyuridae
(Marsupialia). Transactions of the Royal Society of South Australia 96:
125-137.
SMITH, M.J. 1976. Small fossil vertebrates from Victoria Cave, Naracoorte,
South Australia. IV. Reptiles. Transactions of the Royal Society of South
Australia. 100: 39-51.
SMITH, M.J. 1995. Toolache wallaby.. In: Strahan, R. (Ed.) The Mammals of
Australia, pp. 339-340. New Holland Publishers, Sydney, Australia.
SMITH, R.M.H. 1993. Vertebrate taphonomy of Late Permian floodplain
deposits in the southwestern Karoo Basin of South Africa. Palaios. 8: 45-
67.
SOBBE, I.H. 1990. Devils on the Darling Downs- the tooth mark record.
memoirs of the Queensland Museum. 27: 299-322.
SOLÉ, R.V., ALONSO, D. & MCKANE, A. 2002. Self organized instability in
complex ecosystems. Philosophical Transactions of the Royal Society of
London B Series. 357: 667-681.
297
SOLEM, A. 1979. Camaenid land snails from western and central Australia
(Mollusca: Pulmonata: Camaenidae) I. Taxa with trans-Australian
distribution. Records of Western Australian Museum Supplement. 10: 5-
142.
SOLEM, A. 1993. Camaenid land snails from western and central Australia
(Mollusca: Pulmonata: Camaenidae). VI. Taxa from the red centre.
Records of the Western Australian Museum, Supplement. 43: 983-1459.
SPENCER, L.M., VAN VALKENBURGH, B. & HARRIS, J.M. 2003. Taphonomic
analysis of large mammals recovered from the Pleistocene Rancho La
Brea tar seeps. Paleobiology. 29: 561-575.
SPENCER, W.B. 1897. Description of two new species of marsupials from
central Australia. Proceedings of the Royal Society of Victoria. n.s. 9: 5-
11.
STAFFORD, T.W. JR., SEMKEN, H.A. JR., GRAHAM, R.W., KLIPPEL, W.F.,
MARKOVA, A., SMIRNOV, N.G. & SOUTHEN, J. 1999. First accelerator mass
spectrometry 14C dates documenting contemporaneity of non-analog
species in late Pleistocene mammal communities. Geology. 27: 903: 903.
STANISIC, J. 1990. Systematics and biogeography of eastern Australian
Charopidae (Mollusca, Pulmonata) from subtropical rainforests. Memoirs
of the Queensland Museum. 30: 1-241.
STRAHAN, R. 1995. The Mammals of Australia. New Holland Publishers,
Australia.
STEADMAN, D.W., MARTIN, P.S., MACPHEE, R.D.E., JULL, A.J.T., MCDONALD,
H.G., WOODS, C.A., ITURRALDE-VINENT, M. & HODGINS. 2005. Asynchronous
extinction of late Quaternary sloths on continents and islands.
Proceedings of the National Academy of Sciences of the United States of
America. 102: 11763-11768.
STEADMAN, D.W., PREGILL, G.K. & BURLEY, D.V. 2002. Rapid prehistoric
extinction of iguanas and birds in Polynesia. Proceedings of the National
Academy of Sciences of the United States of America. 99: 3673-3677.
STEADMAN, D.W., WHITE, J.P. & ALLEN, J. 2005. Prehistoric birds from New
Ireland, Papua New Guinea: extinctions on a large Melanesian island.
298
Proceedings of the National Academy of Sciences on the United States of
America. 96: 2563-2568.
STEVENSON, J. & HOPE, G. 2005. A comparison of late Quaternary forest
changes in New Caledonia and northeastern Australia. Quaternary
Research. 64: 372-383.
STERN, P.C. (Ed.) 2002. Human Interactions with the Carbon Cycle:
Summary of a Workshop. National Academy Press, Washington, DC.
STODDART, E. 1995. Long-nosed bandicoot. In: Strahan, R. (Ed.) The
Mammals of Australia, pp. 184-185. New Holland Publishers, Sydney,
Australia.
STUART, A.J., KOSINTEV, P.A. HIGHAM, T.F.G. & LISTER, A.M. 2004.
Pleistocene to Holocene extinction dynamics in giant deer and woolly
mammoth. Nature. 431: 684-689.
STUART, A.J., SULERZHITSKY, L.D., ORLOVA, L.A., KUZMIN, Y.V. & LISTER, A.M.
2002. The latest woolly mammoths (Mammuthus primigenius
Blumenbach) in Europe and Asia: a review of the current evidence.
Quaternary Science Reviews. 21: 1559-1569.
STUIVER, M. & POLACH, A. 1977. Reporting of 14C data. Radiocarbon. 19: 355-
363.
SUROVELL, T., WAGUESPACK, N. & BRANTINGHAM, P.J. 2005. Global
archaeological evidence for proboscidian overkill. Proceedings of the
National Academy of Sciences of the United States of America. 102:
6232-6236.
SZALAY, F. 1982. A new appraisal of marsupial phylogeny and classification.
In: Archer, M. (Ed.) Carnivorous Marsupials, pp. 621-640. Surrey Beatty &
Sons and Royal Zoological Society of New South Wales, Sydney.
TATE, G.H.H. 1948. Results of the Archbold Expeditions. No. 59. Studies on
the anatomy and phylogeny of the Macropodidae (Marsupialia). Bulletin of
the American Museum of Natural History. 91: 235-351.
TAYLOR, M.J. & HORNER, E.B. 1973. Systematics of native Australia Rattus.
Bulletin of the American Museum of Natural History. 150: 5-124.
299
THOMAS, O. 1887. On the specimens of Phascologale in the Museo Cicica,
Genoa, with notes on the allied species of the genus. Annali del Museo
Civico di Storia Naturale di Genova. 4: 502-511.
THOMPSON, C.H. & BECKMANN, G.G. 1959. Soils in the Toowoomba area,
Darling Downs, Queensland. Soils and Land Use Series. Commonwealth
Scientific and Industrial Research Organisation, Australia. Melbourne. 28.
THORNE, A., GRÜN, R., MORTIMER, G., SPOONER, N.A., MCCULLOCH, M.,
TAYLOR, L. & CURNOE, D. 1999. Australia’s oldest human remains: age of
the Lake Mungo 3 skeleton. Journal of Human Evolution. 36: 591-612.
TROSCHEL, F. H. 1856-63. Das Gebiß der Schnecken zur Begründung einer
natürlichen Classifikation. Nicolaische Verlagsbuchhandlung Berlin. 1: 1-
252.
TRUEB, L. (Ed.) 1973. Evolutionary Biology of Anurans. Contemporary
research on major problems. University of Missouri Press. Columbia.
TRUEMAN, C.N.G., FIELD, J.H., DORTCH, J., CHARLES, B. & WROE, S. 2005.
Prolonged coexistence of humans and megafauna in Pleistocene
Australia. Proceedings of the National Academy of Sciences of the United
States of America. 102: 8381-8385.
TURNEY, C.S.M. BIRD, M.I., & ROBERTS R.G. 2001a. Elemental �13C at Allen’s
Cave, Nullarbor Plain, Australia: assessing post-depositional disturbance
and reconstructing past environments. Journal of Quaternary Science. 16:
779-784.
TURNEY, C.S.M., KERSHAW, A.P., MOSS, P., BIRD, M.I., FIFIELD, L.K.,
CRESSWELL, R.G. SANTOS, G.M., DI TADA, M.L., HAUSLADEN, P.A. & ZHOU, Y.
2001b. Redating the onset of burning at Lynch’s Crater (North
Queensland): implications for human settlement in Australia. Journal of
Quaternary Science. 16: 767-771.
TURNEY, C.S.M., KERSHAW, A.P., CLEMENS, S.C., BRANCH, N., MOSS, P.T. &
FIFIELD, L.K. 2004. Millennial and orbital variations of El Nin~o/Southern
Oscillation and high-latitude climate in the last glacial period. Nature. 428:
36-310.
TYLER, M.J. 1976. Comparative osteology of the pelvic girdle of Australian
frogs and description of a new fossil genus. Transactions of the Royal
Society of South. Australia. 100: 3-14.
300
TYLER, M.J. 1977. Pleistocene frogs from caves at Naracoorte, South
Australia. Transactions of the Royal Society of South Australia. 101: 83-
89.
TYLER, M.J. 1990. Limnodynastes Fitzinger (Anura: Leptodactylidae) from the
Cainozoic of Queensland. Memoirs of the Queensland Museum. 28: 779-
784.
TYLER, M.J. 1991. Kyarranus Moore (Anura, Leptodactylidae) from the early
Tertiary of Queensland. Proceedings of the Royal Society of Victoria. 103:
47-51.
TYLER, M.J. 1994a. Australian Frogs: A Natural History. Reed New Holland,
Australia.
TYLER, M.J. 1994b. Climatic change and its implications for the amphibian
fauna. Transactions of the Royal Society of South Australia. 118: 53-57.
TYLER, M.J., MARTIN, A.A. & DAVIES, M. 1979. Biology and systematics of a
new limnodynastine genus (Anura: Leptodactylidae) from north-western
Australia. Australian Journal of Zoology. 27: 135-150.
VAN DYCK, S. M. & LONGMORE, N. W. 1991. The mammals records. In:
Ingram, G.J.& Raven, R.J. (Eds.) An Atlas of Queensland’s Frogs,
Reptiles, Birds and Mammals, pp. 284-336. Board of Trustees of the
Queensland Museum, Queensland.
VAN HUET, S. 1999. The taphonomy of the Lancefield swamp megafaunal
accumulation, Lancefield, Victoria. Records of the Western Australian
Museum. Supplement. 57: 331-340.
VASIL’EV, S.A. 2001. Man and mammoth in Pleistocene Siberia. The World of
Elephants- International Congress, Rome 2001. 363-366.
VERMEIJ, G.J., LEIGHTON, L.R. 2003. Does global diversity mean anything?
Paleobiology. 29: 3-7.
VICKERS-RICH, P. 1991. The Mesozoic and Tertiary history of birds on the
Australian plate, Chapter 20. In: Vickers-Rich, P., Monoghan, J. M., Baird,
R.F., & Rich, T.H. (Eds.) Vertebrate Palaeontology of Australasia, pp. 721-
808. Pioneer Design Studio Pty Ltd and Monash University Publications
Committee, Melbourne.
301
VIGNE, J. & VALLADAS, H. 1996. Small mammal fossil assemblages as
indicators of environmental change in northern Corsica during the last
2500 years. Journal of Archaeological Science. 23: 199-215.
VILLA, P. & MAHIEU, E. 1991. Breakage patterns of human long bones.
Journal of Human Evolution. 21: 27-48.
VOLINOVIC, M.M., BUZAROV, D., ADAMOV, J., SIMIC, J.S. & POPOVIC, E. 1996.
Determination of polychlorinated biphenyls and polyaromatic
hydrocarbons in frog liver. Water Science and Technology. 34, 153-156.
VOORHIES, M.R. 1969. Taphonomy and population dynamics of an early
Pliocene vertebrate fauna, Knox County, Nebraska. Contributions to
Geology, University of Wyoming. Special paper No. 1: 1-69.
WALKER, K.F. 1981. Ecology of Freshwater Mussels in the River Murray.
Australian Water Resources Council Technical Paper. Australian
Government Publishing Service. Canberra. 63.
WANG, X., VAN DER KAARS, A., KERSHAW, P., BIRD, M. & JANSEN, F. 1999. A
record of vegetation and climate through the last three glacial cycles from
Lombok Ridge core G6-4, eastern Indian Ocean, Indonesia.
Palaeogeography, Paleoclimatology, Palaeoecology. 147: 241-256.
WATERHOUSE, G.R. 1838. Catalogue of the Mammalia Preserved in the
Museum of the Zoological Society. 2nd Edition. Richard and John Taylor.
London.
WATTS, C.H.S. & ASLIN, H. 1981. The Rodents of Australia. Angus &
Roberston, Sydney.
WEBB, G. & MANOLIS, C. 1989. Crocodiles of Australia. Reed Books. Sydney.
WEBB III, T., SHUMAN, B. & WILLIAMS, J.W. 2003. Climatically forced
vegetation dynamics in eastern North America during the late Quaternary
Period. 1: 459-478.
WELLS, R.T., HORTON, D.R. & ROGERS, P. 1982. Thylacoleo carnifex Owen
(Thylacoleonidae): marsupial carnivore? In: Archer, M. (Ed.) Carnivorous
Marsupials, Vol. 2, pp. 573-586. Surrey Beatty & Sons, Chipping North,
New South Wales.
WELSH, H.H. JR. & OLLIVIER, L.M. 1998. Stream amphibians as indicators of
ecosystem stress: A case study from California's redwoods. Ecological
Applications. 8; 1118-1132.
302
WENTWORTH, C.K. 1922. A scale of grade and class terms for clastic
sediments. Journal of Geology. 30: 377-392.
WESTERN, D. 2001. Human-modified ecosystems and future evolution.
Proceedings of the National Academy of Sciences of the United States of
America. 98: 5458-5465.
WHITEHEAD, D.R. 1981. Late-Pleistocene vegetational changes in
northeastern North Carolina. Ecological Monographs. 51: 451-471.
WHITTINGTON, S.L. & DYKE, B. 1984. Simulating overkill: experiments with the
Mosimann and Martin model. In: Martin, P.S. & Klein, R.G. (Eds.)
Quaternary Extinctions: A Prehistoric Revolution, pp. 451-465. University
of Arizona Press, Tucson.
WIGLEY, T.M.L. 1991. Could reducing fossil-fuel emissions cause global
warming? Nature. 349: 503-506.
WILKINSON, J. 1995. Fossil record of a varanid from the Darling Downs,
southeastern Queensland. Memoirs of the Queensland Museum. 38: 92.
WILLIAMS, S.E., PEARSON, R.G., WALSH, P.J. 1996. Distributions and
biodiversity of the terrestrial vertebrates of Australia’s Wet Tropics: a
review of current knowledge. Pacific Conservation Biology. 2: 327-362.
WILLIG, M.R. 2003. Challenges to understanding dynamics of biodiversity in
time and space. Paleobiology. 29: 30-33.
WILLIS, K.J., BENNETT, K.D. & WALKER, D. 2004. Introduction. One
contribution of 14 to a discussion meeting issue ‘The evolutionary legacy
of the ice ages’. Philosophical Transactions of the Royal Society:
Biological Sciences. 359: 157-158.
WINTER, J.W. 1997. Responses of non-volant mammals to late Quaternary
climatic changes in the Wet Tropics region of north-eastern Australia.
Wildlife Research. 24: 493-511.
WITHERS, P.C. & O’SHEA, J.E. 1993. Morphology and Physiology of the
Squamata. In: Glasby, C.J., Ross, G.J.B. & Beesley, P.L. (Eds.). Fauna of
Australia, Amphibia and Reptilia, Vol. 2a, pp. 172-196. Australian
Government Publishing Service, Canberra.
WITT, G.B. & AYLIFFE L.K. 2001. Carbon isotope variability in the bone
collagen of red kangaroos (Macropus rufus) is age dependent:
303
implications for palaeodietary studies. Journal of Archaeological Science.
28: 247-52.
WOIRNARSKI, J.C.Z., 1992. A Survey of the Wildlife and Vegetation of
Purnululu (Bungle Bungle) National Park and Adjacent Area. Research
Bulletin 6. Department of Conservation and Land Management. Como,
Western Australia.
WOODBURNE, M.O. 1967. The Alcoota Fauna, central Australia: an integrated
palaeontological and geological study. Bureau of Mineral Resources,
Geology and Geophysics, Bulletin 87.
WOODS, J.T. 1960. Fossiliferous fluviatile and cave deposits. In: Hill, D. &
Denmead, A.K. (Eds.). The Geology of Queensland, pp. 393-403. Journal
of the Geological Society of Australia. 7.
WOODWARD, A.S. 1888. Note on the extinct reptilian genera Megalania,
Owen and Meiolania, Owen. Annals and Magazine of Natural History. 6:
85-89.
WORTHY, T.H. & HOLDAWAY, R.N. 2002. The Lost World of the Moa. Indiana
University Press. Bloomington.
WRIGHT, R. 1986. How old is zone F at Lake George? Archaeology in
Oceania. 21: 138-139.
WRIGHT, R.V.S., O’CONNELL, J.F., MORTON, S.R., MARTIN, P.S., HORTON, D.,
GRAYSON, D.K., BOWDLER, S., ANDERSON, A. & FLANNERY, T.F. 1990.
Pleistocene faunal loss: implications of the aftershock for Australia’s past
and future: Comments. Archaeology in Oceania. 25: 64-67.
WROE, S. 2002. A review of terrestrial mammalian and reptilian carnivore
ecology in Australian fossil faunas, and factors influencing their diversity:
the myth of reptilian domination and its broader ramifications. Australian
Journal of Zoology. 50: 1-24.
WROE S. 2005. On little lizards and the big extinction blame game.
Quaternary Australasia. 23: 8-12.
WROE, S., CROWTHER, M., DORTCH, J. & CHONG, J. 2003a. The size of the
largest marsupial and why it matters. Proceedings of the Royal Society of
London B series. 271: 34-36.
304
WROE, S. & FIELD, J. 2001a. Mystery of megafaunal extinctions remains.
Australasian Science. 22(8): 21-25.
WROE, S. & FIELD, J. 2001b. Giant wombats and red herrings. Australasian
Science. 22(10): 18.
WROE, S. & FIELD, J. in press. A review of the evidence for a human role in
the extinction of Australian megafauna and an alternative interpretation.
Quaternary Science Reviews.
WROE, S. FIELD, J., FULLAGER, R. & JERMIN, L.S. 2004. Megafaunal extinction
in the late Quaternary and the global overkill hypothesis. Alcheringa. 28:
291-331.
WROE, S. FIELD, J. & GRAYSON, D.K. 2006. Megafaunal extinction: climate,
humans and assumptions. Trends in Ecology and Evolution. 21: 61-62.
WROE, S., MYERS, T., SEEBACHER, F., KEAR, B., GILLESPIE, A., CROWTHER, M. &
SALISBURY, S. 2003b. An alternative method for predicting body mass: the
case of the Pleistocene marsupial lion. Paleobiology. 29: 403-411.
WROE, S., MYERS, T.J., WELLS, R.T. & GILLESPIE, A. 1999. Estimating the
weight of the Pleistocene marsupial lion, Thylacoleo carnifex
(Thylacoleonidae : Marsupialia): implications for the ecomorphology of a
marsupial super-predator and hypotheses of impoverishment of Australian
marsupial carnivore faunas. Australian Journal of Zoology. 47: 489-498.
ZACHOS, J., PAGANI, M., SLOAN, L., THOMAS, E. & BILLUPS, K. 2001. Trends,
rhythms, and aberrations in global climate 65 Ma to Present. Science.
292: 686-693.
ZHAO, J.-X., XIA, Q. & COLLERSON, K.D. 2001. Timing and duration of the last
interglacial inferred from high resolution U-series chronology of stalagmite
growth in South Hemisphere. Earth and Planetary Science Letters. 184:
635-644.
ZIMOV, A.A., CHUPRYNIN, V.I., ORESHKO, A.P., CHAPIN, F.S. III, REYNOLDS, J.F.
& CHAPIN, M.C. 1995. Steppe-tundra transition: a herbivore-driven biome
shift at the end of the Pleistocene. The American Naturalist. 146: 765-794.
ZWIERS, F.W. & KHARIN, V.V. 1998. Changes in the extremes of the climate
simulated by CCC GCM2 under CO2-doubling. Journal of Climate. 11:
2200-2222.
305
306
APPENDICES
Appendix 1. PRICE, G.J. 2002. Perameles sobbei sp. nov. (Marsupialia,
Peramelidae), a Pleistocene bandicoot from the Darling Downs, south-
eastern Queensland. Memoirs of the Queensland Museum. 48: 193-197.
This paper describes a new species of fossil bandicoot from the Pleistocene
Darling Downs.
Contribution of authors
I collected, prepared and identified the material that was examined in this
paper (with additional support from others noted in the Acknowledgements). I
also supervised the laboring efforts of the volunteers who assisted in the
preparation of fossil material. Additionally, I prepared the original and final
manuscript for publication.
307
308
309
310
311
312
Appendix 2. PRICE, G.J. & HOCKNULL, S.A. 2005. A small adult Palorchestes
(Marsupialia, Palorchestidae) from the Pleistocene of the Darling Downs,
southeast Queensland. Memoirs of the Queensland Museum. 51: 202.
This paper describes an unusual occurrence of a small-sized megafauna
species in the late Pleistocene Darling Downs.
Contribution of authors
Scott A. Hocknull and I collected, prepared and identified the material that
was examined in this paper. I also supervised the laboring efforts of the
volunteers who assisted in the preparation of fossil material. Additionally, I
prepared the original manuscript for publication.
313
A SMALL ADULT PALORCHESTES (MARSUPIALIA,PALORCHESTIDAE) FROM THE PLEISTOCENE OFTHE DARLING DOWNS, SOUTHEAST QUEENSLAND.Memoirs of the Queensland Museum 51(1): 202.Palorchestes is a rare component of the Australian fossilrecord with late Tertiary origins (Black, 1997). Severalspecies have been described, including; P. painei Woodburne1967 (Late Miocene); P. anulus Black 1997 (Late Miocene);P. selestiae Mackness 1995 (early Pliocene); P. parvus DeVis 1895 (Plio-Pleistocene); and P. azael Owen 1874(Pleistocene). Recent collecting from a late Pleistocenedeposit on the eastern Darling Downs, SEQ, recovered asmall dentary not referable to those species of Palorchesteswhere the dentary is known.
Family PALORCHESTIDAE Tate, 1948Palorchestes Owen 1873Palorchestes sp. (Fig. 1)
Material. QMF49455, edentulous right dentary. QML796,Kings Creek, near Clifton, eastern Darling Downs; latePleistocene (see Price, 2004).Description. Dentary broken anteriorly at I1 alveolus,posteriorly below M3 anterior alveolus; edentulous(excepting for in situ, broken, heavily worn protolophid ofM2); gracile, tapering anteriorly; anterior portion flaredbuccally; symphysis elongate, ankylosed; mental foramenanteroventral to P3; diastemal ridge well defined, linguallyoffset, concave lingually. Alveoli measurements in mm: P3:16.3L � 12.7W, M1: 18.6L � 10.9W; M2: 20.5L � 13.6W.Remarks. The dentary is referred to Palorchestes based onthe combination of its large size; presence of lophids; longand narrow symphysial region; gently tapered anterior; andbuccally flared diastema. The ankylosed symphysis, heavilyworn protolophid of M2 and presence of P3 alveoli indicatesthat the individual was an adult. Therefore, morphologicaldifferences between QMF49455 and other Palorchestesspecies are unlikely to be ontogenetic. Measurements ofalveoli suggest that the teeth were similar in size to P. parvus.However, QMF49455 differs from P. parvus, P. azael and P.painei by being more gracile with an anterior margin morebuccally flared; diastemal ridge better defined and linguallyconcave; and diastema proportionately shorter. Comparisonto P. selestiae and P. anulus is not possible as those speciesare known only from the M1. Black (1997) shows P. selestiaeto be markedly larger and P. anulus to be smaller than P.parvus. Hence, QMF49455 may represent an undescribed,
small species of Palorchestes or sexual dimorphism withinsmall-sized Palorchestes spp.Palorchestes spp. generally occur allopatrically showing atrend of increased body size from the mid Tertiary to the latePleistocene (Murray, 1991). QMF49455 is unusual in being asmall adult Palorchestes from the late Pleistocene. A secondspecies of Palorchestes, also recovered from QML796 andrepresented by a RI1, is referable to P. azael (QMF33024).Sympatry in Palorchestes spp. has been noted by Davis &Archer (1997), however, those occurrences may be due totemporally mixed faunas. Here we confirm sympatry of twoPalorchestes species during the late Pleistocene.Literature Cited.DAVIS, A.C. & ARCHER, M. 1997. Palorchestes azael (Mammalia,
Palorchestidae) from the late Pleistocene Terrace Site LocalFauna, Riversleigh, northwestern Queensland. Memoirs of theQueensland Museum 41: 315-320.
DE VIS, C.W. 1895. A review of the fossil jaws of the Macropodidaein the Queensland Museum. Proceedings of the LinneanSociety of New South Wales 10: 74-134.
BLACK, K. 1997. A new species of Palorchestidae (Marsupialia) fromthe late Middle to early Late Middle Miocene Encore LocalFauna, Riversleigh, northwestern Queensland. Memoirs of theQueensland Museum 41: 181-185.
MACKNESS, B. 1995. Palorchestes selestiae, a new species ofpalorchestid marsupial from the early Pliocene Bluff DownsLocal Fauna, northeastern Queensland. Memoirs of theQueensland Museum 38: 603-609.
MURRAY, P.F. 1991. The Pleistocene megafauna of Australia. Pp1071-1164 In Vickers-Rich, P., Monaghan, J.M., Baird, R.F. &Rich T.H. (eds) (Vertebrate Palaeontology of Australasia.Pioneer Design Studio; Lilydale, Victoria).
OWEN, R. 1874. On the fossil mammals of Australia- Part IX.Philosophical Transactions 164: 783-803.
PRICE, G. J. 2004. Fossil bandicoots (Marsupialia: Peramelidae) andenvironmental change during the Pleistocene on the DarlingDowns, southeastern Queensland, Australia. Journal ofSystematic Palaeontology 2(4): 347-356.
TATE, G.H.H. Results of the Archbold Expeditions. No. 59. Studieson the anatomy and phylogeny of the Macropodidae(Marsupialia). Bulletin of the American Museum of NaturalHistory 91: 235-351.
WOODBURNE, M.O. 1967. The Alcoota Fauna, central Australia: anintegrated palaeontological and geological study. Bureau ofMineral Resources, Geology and Geophysics, Bulletin 87.
Gilbert J. Price, Queensland University of Technology,School of Natural Resource Sciences, GPO Box 2434,Brisbane, Queensland; Scott A. Hocknull, QueenslandMuseum, 122 Gerler Road, Hendra, Queensland; 1 January2005.
202 MEMOIRS OF THE QUEENSLAND MUSEUM
FIG. 1. QMF49455, Palorchestes sp. right dentary. A, occlusal view. B, lateral view.
314
Appendix 3. PRICE, G.J. 2005b. Pleistocene megafauna extinction: new
evidence from the Darling Downs, southeastern Queensland. Quaternary
Australasia. 23(1): 15-16.
This paper was an invited research report for Quaternary Australasia. It
provides a historical perspective of the research on the Pleistocene Darling
Downs, significance of the current findings with respect to megafauna
extinction, and possible future directions.
Contribution of authors
I researched and prepared the original and final manuscript for publication.
315
QUATERNARY AUSTRALASIA 23 (1) 15
Debate concerning the extinction of the Australian Pleistocene megafauna has become polarised in recent years. Several proponents favour either climatic or anthropogenic megafauna extinction models. Critical to the debate is the development of accurate chronologies of initial human occupation and megafauna extinction. However, current imprecise and/or lacking chronologies are a contributing factor to the failure to resolve arguments about the causes of megafaunal extinctions. Additional deposits incorporating more complex and detailed ecological analyses and dating at different regional scales are required to resolve issues relating to megafauna extinction.
The Darling Downs, southeastern Queensland has enormous potential to help answer questions relating to megafauna extinction. The Darling Downs is particularly fossil-rich, with over 50 known megafauna-bearing fossil deposits in a small (16 000 km2) geographic area (Molnar and Kurz, 1997). Perhaps most importantly, the deposits may encompass the megafauna extinction episode in eastern Australia (Roberts et al., 2001). Previous palaeoenvironmental interpretations were primarily based on megafauna species occurring in the deposits and are suggestive of expansive grasslands with some woodlands (Molnar and Kurz, 1997). However, such interpretations are limited as few studies have addressed the documentation of detailed stratigraphic, sedimentologic and taphonomic aspects of the deposits. Additionally, past fossil collecting was biased towards the recovery of large-sized megafauna taxa. Small-sized forms are poorly known, thereby limiting previous palaeoenvironmental interpretations.
Recent studies of fossil deposits in the Kings Creek catchment, southern Darling Downs were aimed at incorporating detailed aspects of dating, stratigraphy, taphonomy and palaeoecology to establish a more accurate interpretation of the Pleistocene environment (Price, 2002, 2004; Price et al., 2005; Price andHocknull, 2005; Price and Sobbe, 2005).
RESEARCH REPORTS
Pleistocene megafauna extinction: new evidence from the Darling Downs, southeastern QueenslandGilbert J. PriceSchool of Natural Resource Science Queensland University of Technology ([email protected])
The Kings Creek catchment provides a unique opportunity to examine detailed palaeoecological aspects of a Pleistocene floodplain community in a small geographic area. Fossil accumulations within floodplains are typically transported, and it is commonly difficult or impossible to reliably constrain the sampling area of palaeodrainages. However, regional topography can be used to constrain the size of the Pleistocene Kings Creek catchment using the size of the modern catchment as an analogy. The Pleistocene catchment was relatively small, suggesting that fossil material could not have been transported over distances greater than 20-25 km. Thus, palaeoecological implications represent a small, well-constrained geographic area. Additionally, stratigraphic excavation techniques have allowed recovery of large collections of vertebrate remains that represent temporal sequences.
Radiocarbon dating indicates that the deposits are late Pleistocene (45-40 ka). Depositional processes in the catchment include both high-energy channel and low-energy vertical accretion deposits. Such depositional processes have a range of taphonomic signatures for both large- and small-sized vertebrates occurring in the deposits. Several biases have been observed relating to the differential preservation of mammals versus non-mammal vertebrates. Such biases may be related to fluvial sorting and/or density dependent destruction of different skeletal elements or taxa. Generally, identifiable material appears to have been derived from the surrounding proximal floodplain, an interpretation that is consistent with the geographically small Pleistocene catchment.
Systematic collecting methods targeted the recovery of invertebrates and both large- and small-sized vertebrates. Over 50 species were recovered from the deposits, including typical megafauna taxa (e.g. Megalania, Diprotodon, Protemnodon spp.) as well as new records of entire groups, such as land snails, frogs, skinks, and bandicoots. Most of the new records include extant species, and Pleistocene geographic
316
16 QUATERNARY AUSTRALASIA 23 (1)
range extensions have been documented for several of those taxa. Such assemblages suggest that the late Pleistocene Darling Downs climate was more equable than present, with more available water throughout the year.
Habitat interpretations based on the observed and inferred ecologies of Pleistocene Darling Downs taxa have increased the precision of previous palaeoenvironmental interpretations. A mosaic of habitats occurred on the Pleistocene floodplain including vine thickets, scrublands, open sclerophyllous woodlands interspersed with sparse grassy understories and open grasslands. However, at the time of initial European colonisation, open grasslands dominated the floodplain with woodlands confined closer to hillsides (Fensham and Fairfax, 1997). That suggests that significant habitat changes occurred since the late Pleistocene. Thus far, there is no specific evidence supporting an anthropogenic role in the contraction of late Pleistocene Darling Downs habitats or megafauna extinctions for several reasons. 1) There is no evidence of humans in the megafauna deposits (i.e. there are no cultural artefacts or human remains). 2) The charcoal record is poor suggesting that natural or anthropogenic firing of the Pleistocene landscape was insignificant. 3) Cut-markings on bones relate to feeding by non-human carnivores. 4) The megafauna deposits are 30-35 ka older than the first record of humans in the region. Other ecological and sedimentological data suggest that significant climate change occurred, possibly driving late Pleistocene Darling Downs habitat contractions and species extinctions, irrespective of potential human occupation.
Although it may be over-simplistic to suggest that climate change drove Darling Downs megafaunal extinction, this research highlights the need to expand the project over wider temporal and spatial scales. That will allow testing of human versus climate hypotheses and will more precisely determine the operational details and mechanisms driving megafaunal extinction. It may be the case that humans played a more significant role elsewhere, but there is currently a paucity of data linking megafauna and human interactions.
ReferencesFensham, R. J. and Fairfax, R. J. 1997. The use of the
land survey record to reconstruct pre-European vegetation patterns of the Darling Downs, Queensland, Australia. Journal of Biogeography 24: 827-836.
Molnar, R. E. and Kurz, C. 1997. The distribution of Pleistocene vertebrate on the eastern Darling Downs, based on the Queensland Museum collections. Proceedings of the Linnean Society 117: 107-134.
Price, G. J. 2002. Perameles sobbei, sp. nov. (Marsupialia, Peramelidae), a Pleistocene bandicoot from the Darling Downs, south-eastern Queensland. Memoirs of the Queensland Museum 48: 193-197.
Price, G. J. 2004. Fossil bandicoots (Marsupialia, Peramelidae) and environmental change during the Pleistocene on the Darling Downs, southeastern Queensland, Australia. Journal of Systematic Palaeontology 4: 347-356.
Price, G. J. and Hocknull, S. A. 2005. A small adult Palorchestes (Marsupialia, Palorchestidae) from the Pleistocene of the Darling Downs, southeast Queensland. Memoirs of the Queensland Museum 51: 202.
Price, G. J. and Sobbe, I. H. 2005. Pleistocene Palaeoecology and environmental change on the Darling Downs, southeastern Queensland, Australia. Memoirs of the Queensland Museum 51: 171-201.
Price, G. J., Tyler, M. J. and Cooke, B. N. 2005. Pleistocene frogs from the Darling Downs, southeastern Queensland, Australia, and their palaeoenvironmental significance. Alcheringa 29: 171-182.
Roberts, R. G., Flannery, T. F., Ayliffe, L. K., Yoshida, H., Olley, J. M., Prideaux, G. J., Laslett, G. M., Baynes, A., Smith, M. A., Jones, R. and Smith, B. L. 2001. New ages for the last Australian megafauna: continent-wide extinction about 46,000 years ago. Science 292: 1888-1892.
RESEARCH REPORTS
317