primate evolution (65 - 5 mya). emergence of primates first primates plesiadapiforms or adapids...
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Primate Evolution(65 - 5 mya)
Primate Evolution(65 - 5 mya)
Emergence of PrimatesEmergence of Primates
First primates Plesiadapiforms or adapids and omomyids?
Environment - Cretaceous to Palaeocene Continental drift (Pangea = Laurasia & Gondwanaland)
Success of primates Arboreal theory
Visual predation hypothesis (Cartmill 1972, 1992)
Early Primates
Prosimians (65mya)Monkeys (35mya)Apes (23mya)Hominids (5mya)
Early Primates - Traits
Common physical primate traits: Dense hair or fur covering Warm-blooded Live young Suckle Infant dependence
Common social primate traits: Social life Play Observation and imitation Pecking order Common Primate Traits
Continents at the end of the MeszoicContinents at the end of the Meszoic
Here are the placement of the continents at the end of the Cenozoic and beginning of the Mesozoic, about 65 m.y.a.
The primate order is divided into two suborders
The prosimians, or lower primates include the lemurs, lorises, tarsiers, and tree shrews,
while the anthropoids, or higher primates include monkeys, apes, and humans
Classification of Primates
Prosimians are generally small ranging from species the size of a mouse up to those as large as a house cat
They are arboreal, have five digits on each hand and foot with either claws or nails, and are typically omnivorous
They have large, forwardly directed eyes specialized for night vision, hence most are nocturnal
Prosimians
Tarsiers are prosimian primates
• Ring-Tailed Lemurs are also prosimians
As their name implies pro means "before," and simian means "ape”. prosimians are the oldest primate
lineage, and their fossil record extends back to the Paleocene.
During the Eocene prosimians were abundant, diversified, and widespread in North America, Europe, and Asia.
Prosimians
Early Cenozoic PrimatesEarly Cenozoic Primates
The earliest primates date to the first part of the Cenozoic
(65-54 m.y.a.).
The Eocene (54-38 m.y.a.) was the epoch of prosimians
with at least 60 different genera in two families.
The omomyid family lived in North America, Europe, and
Asia and may be ancestral to all anthropoids.
The adapid family was ancestral to the lemur-loris line.
Notharctus, a primitive Eocene prosimian; found in North America.
Eocene Prosimian
OmomyidOmomyid
An artist’s reconstruction of Shoshonius, a member of the Eocene omomyid family.
AnthropoidsAnthropoids
Anthropoids branched off from the prosimians during the
Eocene. Anthropoid eyes are rotated more forward compared to
prosimians.
Anthropoids have a fully enclosed bony eye socket.
Anthropoids have a dry nose separate from the upper lip.
Anthropoids have molar cusps.
New World Monkey
New World Monkeys constitute a superfamily belonging to the suborder Anthropoidea (anthropoids)
Another superfamily of the anthropoids: the Old World Monkeys
Old World Monkey
The third superfamily is the great apes, which include gorillas and chimpanzees.
Great Apes
Undisputed remains of early anthropoids date from 34 million years ago; Fayum area southwest of Cairo, Egypt Found remains from different types of anthropoids,
including: Parapithecids (monkey-like) Propliopithecids (ape-like) - some believe that the
common ancestor for both Old and New World monkeys belonged to this group Best known of group - Aegyptopithecus which is believed to
be after the fashion of the howler monkey
Early AnthropoidsEarly Anthropoids
Skull of Aegyptopithecus zeuxis
One of the Earliest Anthropoids
Miocene Period: 24 to 5.2 million years ago First hominid appeared in Africa where remains have been found dating
5 million years old Early Miocene Period
Proconsul found in sites in East Africa Middle Miocene
Kenyapithecus 16 to 10 million years ago with molars resembling modern hominoids
Late Miocene Apes Movement to Europe and Asia due to warmer weather conditions;
migration from Africa Two main groups:
Sivapithecus - link to orangutans Dryopithecus
Miocene AnthropoidsMiocene Anthropoids
ProconsulProconsul
A skull of Proconsul africanus from the Kenya National Museum.
Proposed appearance of Proconsul africanus.
KenyapithecusKenyapithecus
Fossil jaw bones fromEquatorius, probably ancestral to Kenyapithecusafricanus and K. wickeri.
SivapithecusSivapithecusSivapithecus belongs to
the ramapithecid genera along with Gigantopithecus.
Sivapithecus is now believed to be ancestral to the modern orangutan.
A Sivapithecus skull.
GigantopithecusGigantopithecusGigantopithecus is the largest
primate that ever lived, some standing over 10 feet tall and weighing 600 pounds.
Since it died out around 250,000 years ago, it coexisted with Homo erectus.
Some people believe it is still alive today as the yeti and bigfoot.
A reconstruction of Gigantopithecus by Russel Ciochon and Bill Muns.
DryopithecusDryopithecus
Dryopithecus lived in Europe
during the middle and late
Miocene.
This group probably includes
the common ancestor of the
lesser apes (gibbons and
siamangs) and the great apes.
Dryopithecus has the Y-5
arrangement of molar cusps
typical of Dryopithecus and of
hominoids.
OreopithecusOreopithecus
Oreopithecus bambolii lived between 9-7 m.y.a and spent
much of its time standing upright and shuffling short
distances.
Its big toe splayed out 90 degrees from the other toes.
Oreo is Greek for “mountain”
Early HominidsEarly Hominids
Chronology of Hominid EvolutionChronology of Hominid Evolution
The Pleistocene (2 m.y.a. to 10,000 B.P.) is the epoch of
human life.
Lower Pleistocene (2 to 1 m.y.a.): Australopithecus and early
Homo
Middle Pleistocene (1 m.y.a. to 130,000 B.P.): Homo erectus
and archaic Homo sapiens
Upper Pleistocene (130,000 to 10,000 B.P.): modern Homo
sapiens
Hominid Evolution
Homo habilis (2.0 – 1.6mya)
H. rudolfensis (2.4-1.6mya)
H. erectus (1.9-27kyBP)
H. heidelbergensis (800-100kyBP)
H. neanderthalensis (300-30kyBP)
H. sapiens (130kyBP – present)S
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The Varied AustralopithecinesThe Varied AustralopithecinesThere are two major hominid genera: Australopithecus and
Homo.However, in 1992 Berhane Asfaw and Tim D. White
discovered substantial remains considered to be from hominids ancestral to the australopithecines; these remains have been called Ardipithecus ramidus (thus establishing a third hominid genus) and dated a 4.4 m.y.a.
A more recent (1995, by Maeve Leakey and Alan Walker) discovery has been named Australopithecus anamensis and been dated at 4.2 m.y.a.
Evolution of BipedalismEvolution of Bipedalism
Tool use and bipedalism (Darwin/Washburn)
Energy efficiency and bipedalism (Isbell/Young)
Radiator theory (Falk)
Body temperature and bipedalism (Wheeler)
Habitat variability and bipedalism (Potts)
Reproduction and bipedalism (Lovejoy)
Canine reduction and bipedalism (Jolly)
SkeletonsSkeletons
Comparison of human and chimpanzee skeletons.
PelvesPelves
A comparison of human and chimpanzee pelves.
DentitionDentition
Comparison of dentition in ape, human, and A. afarensis palates.
Crania ComparisonCrania Comparison
New World MonkeyGreat Ape
Human
Hominids show a trend toward a large and internally reorganized brain.An increase in brain size and organization is apparent when comparing the brains of the new world monkey, the great ape, and the human.
Discovered in Chad in 2002 and dated at nearly 7 million years, this skull is presently the oldest known hominid
Sahelanthropus tchadensis
The Species of Australopithecus The Species of Australopithecus
Ardipithecus ramidus 4.4 - ? million years agoA. anamensis 4.2 - 3.9A. afarensis 4.2 - 2.5A. bahrelghazali 3.5 - 3.0A. africanus 3.5 - 2.5P. aethiopicus 2.7 - 2.3A. garhi 2.5 - ?P. boisei 2.3 - 1.3P. robustus 2.0 - 1.0
Phylogenetic TreePhylogenetic Tree
Phylogenetic tree for African apes and hominids.
Ardipithecus ramidusArdipithecus ramidusHominid who walked bipedally 4.4 myaDiscovered in 1992 by Tim White in Aramis, Ethiopia (as
yet largely unpublished)Distinct enough to be a new species?
ape-like dentition bipedal locomotion overall hominid-like skeleton small cheek teeth with thin enamel and large canines arm bones are hominid-like foramen magnum indicates bipedalism
Australopithecines: Robust or Gracile?Australopithecines: Robust or Gracile?Two species of australopithecines: robust and gracileMost palaeoanthropologists classify robust species as
Paranthropus and gracile species as Australopithecus, although both species are australopithecines.
Gracile A. anamensis, A. afarensis, A. bahrelghazali, A. africanus, A.
garhi smaller dentition, lighter musculature
Robust P. aethiopicus, P. boisei, P. robustus larger teeth, massive jaws, sagittal crest
AustralopithecinesAustralopithecines
Skulls of Robust (left) and Gracile (right) Australopithecines.
Australopithecus anamensisAustralopithecus anamensis
4.2 - 3.9 mya
average weight - 110 pounds
primitive bipedalism, possibly
climbing
found primarily in Kenya
discovered in 1995
Australopithecus afarensisAustralopithecus afarensis4.2 mya, with oldest definite specimen placed at 3.8 myaapelike features (long arms, prognathic face, toothrow, brain
capacity)pelvis, leg, feet, and foramen magnum all indicate bipedalism
first discovered by Don Johanson in 1974 and called “Lucy”
thought to be the “missing link” until A. anamensis was discovered 20 years later
Australopithecus afarensisAustralopithecus afarensis
Left: Trail of footprints of A. afarensis made in volcanic ash, discovered by Mary Leakey at Laetoli.
Right: Close-up of footprint at Laetoli
Re-creation of a Pliocene landscape showing members of Australopithecus afarensis gathering and eating various fruits and seeds.
Landscape with A. afarensis
Australopithecus bahrelghazaliAustralopithecus bahrelghazali3.5 - 3.0 myadiscovered by Michel Brunet in Bahr el Ghazal, Chad in
1995assumed bipedalism (few post-cranial remains)
A. africanusA. africanus
3.5 - 2.5 mya 3.8 - 4.5 feet tall, 55-
130 lbs ape-like tibia, grasping
big toes wide pelvis, parabolic
tooth row primitive bipedalism first found by Raymond
Dart in Taung, South Africa in 1925
Australopithecus garhiAustralopithecus garhi
possibly the direct ancestor of early Homo
larger molars than afarensis, but not as large as
Paranthropus
lacks enlarged brain of early Homo
toolmaker and butcher
2.5 mya
Paranthropus aethiopicusParanthropus aethiopicus2.7 to 2.3 myaearliest robust australopithecine, but least well known larger dentition, cheek bones, dish-shaped faces, sagittal
crestsresembles afarensis but with increases in dental apparatus
sizeassumed bipedalismfirst discovered in Omo, Ethiopia, 1967-1974
The Black Skull - P. aethiopicusThe Black Skull - P. aethiopicus
The “black skull”, dated to 2.5 m.y.a., was discovered by Alan Walker in 1985 near Lake Turkana.
Paranthropus boiseiParanthropus boisei2.3 - 1.3 mya; 4.1 - 4.5 feet tall, 75-175 lbsdiscovered by Louis Leakey at Olduvai Gorge in Tanzania
in 1959originally named Zinjanthropusdished face, sagittal crestparabolic toothrow, wide pelvisprimitive bipedalism
Paranthropus robustusParanthropus robustus2.0 - 1.0 mya; 3.6 - 4.3 feet tall; 70-175 lbsdiscovered by Robert Broom in 1938 at Kromdraai, South
Africa, who created the name Paranthropusdished face, sagittal crestparabolic toothrow, human-like
big toes, wide pelvis, no diastema
for caninesbipedalism (more primitive than
modern human walking)
Map of Australopithecine FindsMap of Australopithecine Finds
Map of Australopithecus sites in Africa, with a focus on the East African rift valley and limestone caves of South Africa.
Facts about AustralopithecinesFacts about Australopithecines
Species Dates(m.y.a.)
Known Dist.
Important Sites
Body Weight
(Mid-sex)
Brain Size(Mid-sex)
(cm3)
Homo sapiens sapiens
modern world-wide Beijing, New York, London, Nairobi
60kg/132lbs 1,350
Pan troglodytes modern central Africa
Gombe, Mahale
42kg/93 lbs 390
Australopithecus boisei
2.6? to 1.2 E. Africa Olduvai, East
Turkana
39 kg/86 lbs 490
Australopithecus robustus
2.6? to 2.0? S. Africa Kromdraai Swartkrans
37 kg/81 lbs 540
Facts about AustralopithecinesFacts about Australopithecines
Species Dates(m.y.a.)
Known Dist.
Important Sites
Body Weight
(Mid-sex)
Brain Size(Mid-sex)
(cm3)
Australopithecus africanus
3.0 to 2.5? S. Africa Taung, Sterkfontein
36 kg/79 lbs 490
Australopithecus afarensis
3.8 to 3.0 E. Africa Laetoli, Hadar
35 kg/77 lbs 430
Australopithecus anamensis
4.2 E. Africa Kanapoi Insufficient data
no published
skulls
Ardipithecus ramidus
4.4 E. Africa Aramis Insufficient data
no published
skulls
Homo habilis
Artist’s representation of a Homo habilis band as it might have existed two million years ago.
612 cc brain
2.3 - 1.6 mya
first toolmaker
prognathic face, brow ridge
probable meat-eater
possibly arboreal
discovered in 1960 by Leakeys
no speech
A reconstruction of the skull of Homo erectus, a widely distributed species whose remains have been found in Africa, Europe, India, China, and Indonesia.
Skull of Homo erectus
Homo erectus
1891 - Eugene Dubois discovers H. erectus in JavaDubois calls it Pithecanthropus erectus initially, also dubbed “Java Man”finds in China called Sinanthropusdates from 1.9 mya to 27,000 years B.P.994 cc brain size (compare to 612 for H. habilis)Acheulean tool industry
Photograph of Nariokotome boy, an early Homo erectus found near Lake Turkana, Kenya.
Neanderthal Skull
Reconstructed Neanderthal skull
The Neanderthals were characterized by prominent heavy
brow ridges and weak chin
Homo neanderthalensis
discovered in the Neander Valley (Tal) near Dusseldorf, 1856
massive brain--about 1,400cc on average
large torso, short limbs, broad nasal passages
later remains show decrease in robustness of the front teeth and face, suggesting use of tools replaced teeth
retained occipital torus, some mid-facial prognathism
The skull of the classic Neandertal found in 1908 at La Chapelle-aux-Saints.
Homo sapiens
Archaic – 100,000 to 35,000 years BP Sometimes called Homo
sapiens and Homo sapiens neanderthalensis
Modern – 35,000 years BP to present Anatomically modern Sometimes called Homo
sapiens sapiens
Cro-Magnon Man
Cro-Magnon humans
35,000 years B.P. in western Europe to 17,000 years B.P.
1,600 cc cranial capacity
Name comes from a hotel in France
Not a different species, just old Homo sapiens from Europe
Artist’s reconstruction of a Cro-Magnon man
Archaic H. sapiens CultureArchaic H. sapiens Culture
Art
Traces of art found in beads, carvings, and paintings
Cave paintings in Spain and southern France showed a marked degree of skill
Female figurines
27,000 to 22,000 years B.P.
Called “venuses,” these figurines depicted women with large breasts and broad hips• Perhaps it was an example of an ideal type, or
perhaps an expression of a desire for fertility
Archaic H. sapiens CultureArchaic H. sapiens Culture
Cave paintings Mostly animals on bare walls Subjects were animals favored for their meat
and skins Human figures were rarely drawn due to taboos
and fears that it would somehow harm others
Cave paintings from 20,000 years ago at Vallon-Pont-d’Arc in southern France (left) and from Lascaux, in southwest France
Upper Palaeolithic – Hotbed of CultureUpper Palaeolithic – Hotbed of Culture
40 – 10k yBP Shelters
15,000 yBP Ukraine Some made with mammoth bones Wood, leather working; carpentry
Tools From cores to blades Specialization Composite tools Bow and arrow
Domestication of dogs Gathering rather than hunting became
the mainstay of human economies.
Top: Straw Hut
Left: Mammoth bone hut
Bottom: Tool progression
Modern Homo SapiensModern Homo SapiensRegional-Continuity Model (Milford Wolpoff, UMich)
Humans evolved more or less simultaneously across the entire Old World from several ancestral populations.
Rapid-Replacement Model (Chris Stringer, NHM London)
Humans evolved only once--in Africa from H. heidelbergensis ancestors--and then migrated throughout the Old World,
replacing their archaic predecessors. Also called the “Out of Africa” and “Killer Ape” hypothesis.
Social OrganizationSocial Organization
Hunter-gatherer analogy Small group, low population density, nomadism, kinship
groupsMigration
North America was the last colonized by hominids. Beringia (land bridge) between Russia and Alaska Asian origin of Native Americans 30,000 to 12,000 years B.P. was first migration