1 introduction to taxonomy and biodiversity_hue

The diversity of biodiversity issues:

from definition to conservation and

sustainable use

1. Introduction to Taxonomy and Biodiversity

What is Biodiversity?

Temporal patterns of biodiversity

Value of biodiversity

Threats to biodiversity

Conservation of biodiversity

Spatial patterns of biodiversity

Hue University, January 2009

Bios & diversitas: the diversity of life


Life evolves to a spatio-temporal, context-dependent , dynamic and functionality complex system which is largely unpredictable

Life? Evolution

Self-replication

Growth and differentiation

Metabolism

Self-regulation

Inherent interaction with environment









« The variety of organisms considered at all levels, from genetic variants belonging to the same species through arrays of species to arrays of genera, families, and still higher taxonomic levels; includes the variety of ecosystems, which comprise both the communities of organisms within particular habitats and the physical conditions under which they live »

E.O. Wilson, 1992

Biodiversity is a fundamentally multidimensional concept









« … the conservation of biological diversity, the sustainable use of its components and the fair and equitable sharing of the benefits arising out of the utilization of genetic resources, including by appropriate access to genetic resources and by appropriate transfer of relevant technologies, taking into account all rights over those resources and to technologies, and by appropriate funding»

Article 1 CBD

Biodiversity is also a value-loaden concept









Diversity?

PhylaClassesOrders

FamiliesGeneraSpecies

SubspeciesPopulationIndividuals

Organismaldiversity

BiomesBioregionsLandscapesEcosystems

HabitatsNiches

Population

Ecological diversity

PopulationIndividuals

ChromosomesGenes

Nucleotides

Genetic diversity









Elements of biodiversity form nested hierarchies









Encompasses the scales of ecological differences from populations, through niches and habitats, up to biomes

Distinguishing or breaking-up of the elements is arbitrary due to large interconnectiviness between systems(e.g. how to consider a coral reef without simultaneously considering sea grass beds, mangrove forests, sandy beaches, …)

Ecological diversity What is Biodiversity?









Organismaldiversity

But how are these categories determined?

Individual

Population

(from Campbell & Reece 2002)


Encompasses the taxonomic hierarchy and its components








Taxonomy = the scientific discipline that detects, describes and classifies taxa

Systematics = taxonomy + evolutionary relationships

Question 1 - What is an individual?

A unique genotypic combination and the phenotypical expression thereof, belonging to a population


Organismaldiversity What is Biodiversity?








Question 2 - What is a population?

A population consists of individuals that share the same gene pool. The gene pool of a species or a population is the complete set of unique alleles that would be found by inspecting the genetic material of every living member of that species or population.


Organismaldiversity











Question 3 - What is a species?





± 1940: a species is a group of interbreeding natural populations that do successfully mate or reproduce with other such groups

1989: a species is the smallest group of cohesive individuals that share intrinsic cohesive mechanisms

(but more definitions exist…)








Question 4 – How are species classified?

• On similarity?• On evolutionary relationship according to common

ancestry?












Limpet Barnacle LobsterChimp Man Rabbit

On evolutionary relationshipOn similarity On similarity

On evolutionary relationship

tim

e

form

tim

e

form

Pattern of evolution matters








Lowest level in the hierarchy of biodiversity

Encompasses the components of the genetic coding that structure organisms (nucleotides, genes,

chromosomes) and variation in the genetic make-up between individuals within a population and between populations

Genetic diversity










Genetic diversity within a population

Genetic diversity










Genetic diversity between

populations

Geographic variation in genetic diversity between isolated populations of the house mice (Mus musculus) on Madeira (from Campbell & Reece 2002)

Genetic diversity










Genetic diversity between populations

Genetic variation in the VacA gene of Helicobacter pylori(from Blaser 2005)

Genetic diversity










Genetic diversity


Organismaldiversity

Genetic diversity between populations can also reveal cryptic diversity


(from Page & Charleston 1998)








The n-dimensional web of life spun

through time and space










Global diversity = the number of taxa extant in the present day or at any given time in the geological past Reconstructing the trajectory of life’s history is important as it enables better understanding of:

- the evolutionary ‘forces’- the fate of biodiversity in the face of man-induced global change (e.g. global warming, desertification,deforestation)

Why understand biodiversity through time?









Two main sources of information point to the amount of past biodiversity

Fossil recordScattered and largely incompleteBiased for taxa

Molecular evidenceComparative analyses of sequencesMolecular clock

Seldom agreement between the sources (especially in dating, but also in patterning)

Knowledge predominantly on higher taxa rather than species

Timed branching trees representing hypotheses of phylogenetic relatedness

e.g. molecular evidence suggests origination of at least 6 animal phyla deep in the Precambrium; i.e. +400 my earlier than the fossil record








Errors associated with sources

Fossil record Molecular evidence

Underestimation due to likelihood of fossilisation and

recovery of oldest fossils

Nature and dynamics of molecular clock is known to be variable

across taxa









But paleontological evidence grows...








...as does molecular, cladistic and biogeographic evidence

(From Cooper & Fortey, 1998)








(From Cooper & Fortey, 1998)

...as does molecular, cladistic and biogeographic evidence








By using the analogy of a clock, timing of key episodes in the history of life can easily be visualised

(from Des Marais 2005)









Marine families

Three main pulses of diversification:early CambrianOrdovicianthrough Mesozoic and Cenozoic

Five major mass extinctions:late Ordovicianlate Devonianlate Permianlate Triassicend-Cretaceous

Two main stabilization periods:Mid to late Cambrianmost of the Paleozoic









Marine families


• Transitions in taxonomic composition

• Sequential domination by different groups (Sepkoski’s three evolutionary fauna’s) during each of the era’s:

Cambrian fauna (trilobites) Paleozoic fauna (articulate brachiopods, stalked crinoids, bryozoans, hard corals,…) Modern fauna (gastropods, bivalves, echinoids,…)








(From Erwin 1996)








Marine and terrestrial vertebrate orders

younger faunas and floras achieve higher diversity









(From Gould 1994)








Speciation = adding speciesExtinction = taking species away

Rise of biodiversity => speciation > extinctionStasis of biodiversity => speciation = extinctionDecline of biodiversity => speciation < extinction

Biodiversity = dynamic!

Turnover in biodiversity is a natural phenomenon

90-98 % of all the species that ever existed have gone extinct

Taxa have a ‘life span’









(from Raup 1994)

Temporal patterns of biodiversity - extinctions

Species have an average life span (5-10 Myr)

Strong skewness in life span of genera (most short lived, few persist much longer = living fossils, e.g. Latimeria)

Longest living genus = 160 Myr

Substantial variation in life span of species in taxonomic groups








Mass extinctions - past









Mass extinctions - present








• Species in different taxonomic groups persist for periods with considerable variation

• Extinctions are taxonomically clumped, often disproportionally large in species-poor groups => great loss of genetic diversity

• Extinctions reflect extrinsic factors => marine groups have lower natural extinction rates (greater buffering capacity of environment)

• Extinctions also have intrinsic factors (e.g. inbreeding depressions)

• Mass extinctions ‘only’ account for 4%

• Absolute extent seems neglegible

• Disruption of pattern development is significant (elimination of bauplans, lazarus taxa survive)









Different spatial scales:Alfa diversity: diversity within local assemblage, community or habitat

Beta diversity: rate and extent of turnover between communities, i.e. along a gradient

Gamma diversity: diversity within a geographical area = sum alfa + beta









Understanding of the geographical patterns of biodiversity facillitates, i.a.:

– Understanding the impact / spread of alien, invasive species

– Control of diseases and their vectors

– Understanding the likely effect of local or global environmental change on the functioning of ecosystems and the maintenance of biodiversity

=> In situ conservation and sustainable use

Why understand spatial biodiversity?









How is biodiversity spatially spread?

1. More high level taxonomic units (phyla, classes) in marine systems (e.g. 90% of all known classes are marine, but only 15 % of known

species are marine)

?

Origin oflife

Heterogenity of

environment

Complexity of

environment

Pattern of

herbivory

Distribution of

body size

Age and continuity of marine systems









2. Latitudinal gradients in species richness:

• From high to low latitudes the average species richness within a sampling area of a given size increases (especially visible for terrestrial and freshwater species)

• How general is this pattern? e.g. declines appear faster in Northern than in Southern Hemisphere; disrupted through positional (longitude, elevation, depth,...) and environmental (topography, aridity,...) variables

• Gradient is consequence of the balance of speciation and immigration and extinction and emigration

• Mechanism? A gordian knot of chance, historical perturbation, environmental stability, habitat heterogenity, productivity, interspecific interactions,...








Spatial patterns in species richness

(from Gaston 2000)









3. Species-energy relationships

greater energy availability

greater biomass can be supported in an area

more individual organisms coexist in viable populations

Increase in species richness with energy availability

(from Gaston 2000)








4. Relationship between local and regional richness - How does diversity at one scale relate to another scale?


Type I: local richness is proportional to, but less than, regional richness

Type II: local richness attains a ceiling, whereas regional richness continues to increase

Most systems exhibit type I and thus regional richness seems to be a prime driver for local richness

(from Gaston 2000)









5. Taxonomic covariance in species richness?

Positive relationships between different taxonomic groups not necessarily imply covariance

Covariance might be due to:• sampling effort• trophic relations• random effects

Patterns cannot be extrapolated from one group to another

(from Gaston 2000)








Broad-scale picture:

1. Terrestrial biogeographic regions


(delimited on the composition of biota)

(from Olson et al 2000)









2. Marine Biogeographic Regions


(delimited mainly with physical characteristics - e.g. temperature regimes, currents, biochemical features,...)









2. Marine Biogeographic Regions

(but increasingly also on biological data,...)


(from Roberts et al 2002)








Broad-scale pictures with refined resolution:


From biomes

Delimited on the basis of areas in terms of:

• environmental conditions;• habitat structure• patterns of biological complexity









Broad-scale pictures with refined resolution:


(from Olson et al 2000)• Representing distinct biotas• Reflecting the distributions of a broad range of fauna and flora

...to ecoregions










(Source: www.millenniumassessment.org)








Direct Drivers

Indirect Drivers

EcosystemServices

Human Well-being

Direct Drivers of Change Changes in land use Species introduction or

removal Technology adaptation and

use External inputs (e.g.,

irrigation) Resource consumption Climate change Natural physical and

biological drivers (e.g., volcanoes)

Indirect Drivers of Change Demographic Economic (globalization,

trade, market and policy framework)

Sociopolitical (governance and institutional framework)

Science and Technology Cultural and Religious

Human Well-being and Poverty Reduction

Basic material for a good life

Health Good Social Relations Security Freedom of choice and

action

(Source: www.millenniumassessment.org)









Some 30,000 edible plant species exist

Today, only 20~30 species of plants feed the world

Only 4 (rice, wheat, maize and banana) are staple crops.

Diversity is critical for developing new strains and breeds, i.e. that suit a particular environment or are resistant to pests or disease and as a source of new crops

Source: © AMNH-CBC

Some concrete examples: food

"Copyright 2003, by the authors of the material, with license for use granted to the Center for Biodiversity and Conservation of the American Museum of Natural History. All rights reserved."

Source: National Geographic









Alternative food sources need tapping

Laos

Source L. Sanoamuang

Triangular shelter along the shore in the Xe Lanong River (A) where locals collect the copepods with a traditional net (B, C).

The concentrated catch (D) is called pla kayong








Allodiaptomus esculentus sp.n.

female (1.8 mm) male (1.5 mm)









About 80% of the people in developing countries use plants as a primary source of medicine.

57% of the 150 most-prescribed drugs have their origins in biodiversity

Source: © AMNH-CBC

Some hard examples: medicine










Forests and other vegetation modify climate: by affecting sun reflectance, water vapor release, wind patterns and moisture loss. Forests help maintain a humid environment, for example, half of all rainfall in Amazon basin is produced locally from forest-atmosphere cycle

Source: Ph. Kok (RBINS)

Some hard examples:Climate








• Filter excess nutrients and trap sediments that would otherwise impact neighboring marine and aquatic areas

Other services:• Minimizes damage from

waves and floods• Serves as a nursery for

juvenile commercial fish • Provides habitat for many

birds, fish, and shellfish Source: Ersts © AMNH-CBC

Example: Coastal wetlands and mangroves

Some hard examples: soil and water conservation









Some hard examples: nutrient cycling

Nature Vol. 433: 566-567








Some hard examples: nutrient cycling

Gende & Quin, 2006







Hue University, January 2009Source: Brumbaugh © AMNH-CBC ; http://research.amnh.org/biodiversity/crisis/index.html

Biodiversity and ecosystem functioning








Biodiversity and ecosystem functioning

Minimum of species for ecosystem functioning

Certain thresholds for ecosystem functioning

Unpredictable response of

functioning of ecosystem

=> Ecological equivalency among species (redundancy)








A value politicians understand readily

Global gross national product = 18 trillion USDollar

Estimated value of all ‘ecosystem services’ > 33 trillion USDollar









Check it out at: http://www.biopat.de









Threats to Biodiversity

Multiple, often interacting, threats such as

“HIPPO”

• Habitat loss, degradation, fragmentation• Invasive Alien Species

• Population growth • Pollution

• Overexploitation

Global Change








Threats to Biodiversityhabitat destruction

(from Pimm & Raven, 2000)








Threats to Biodiversityhabitat fragmentation

• Small fragments small populations of fauna vulnerable to extinction. • Separated fragments unlikely to be recolonised.• Small fragments little interior habitat (edge has a different climate and favours different species) extinction of those species.

Solution? • Corridors of native vegetation solve the problem of isolation but not the loss of interior habitat. • Enlarged fragments to create more interior habitat, but do not relieve the degree of isolation








Threats to Biodiversityalien invasive species

(from: Shirley & Kark, 2006)








Threats to Biodiversityalien invasive species

Some figures (cf McNeely 2001):








Threats to BiodiversityPopulation growth

(from Cincotta et al, 2000)








Threats to BiodiversityPopulation growth

FIGURE 2. Human population densities (a) and annual growth rates ( b) in the 25 global biodiversity hotspots (1–25)

(from Keilman 2003)

Decline and fall in household sizes








Threats to Biodiversityoverexploitation








Threats to Biodiversityglobal change

Over the past 100 years Earth has become warmer (the past 30 years were the

warmest of the last millenium!) and precipitation regimes have changed…









…affects biodiversity

(from: Millien et al., 2006)








(from Woods Hole Research Centerhttp://www.whrc.org/carbon/index.htm)









(from Rodrigues, 2006)

Threats to Biodiversityextinction by numbers








Alarm! by 2050 biodiversity will have halved

Threatened plant species:

8,500+

Threatened animal species: 8,400+

IUCN-world congress (Barcelona, 2008)• Since 1600: 700+ animal – and 800+ plant species

have definitely gone extinct• Severe underestimation of reality• by 2025, 20 % will have disappeared• by 2050, 30 % more will have disappeared

Situation at the start of the 21st centuryLargest deforestation – often illegal – occured between 2001 and 2003








Conservation of Biodiversity

Conservation biology = a multidisciplinary science

Natural sciences

Conservation biology

Social sciences

BiologyEcologyEvolutionGeneticsBiogeography

Species managementReserves designRestorationConservation

SociologyEconomyPoliticsLawPhilosophy








Conservation of BiodiversityPragmatic approach

focus on threatened, endemic-rich areas – terrestrial hotspots

(1.4 % of land area that contains an estimated 45 % of terrestrial plant species and 35 % of terrestrial vertebrates )

(from Myers et al 2000)








Conservation of BiodiversityPragmatic approach

focus on threatened, endemic-rich areas – marine hotspots increasingly documented

(from Roberts et al 2002)








Biogeography!

Dependant on stable taxonomy & systematics

Aims to explain the structure, function and history of the geographical ranges of biota

Ecology(biocoenose)

Population-genetics(gene-flow, metapopulation)

History(‘historical ecology’)

Conservation of BiodiversityScientific approach








Descriptive biogeographyFloristics and faunistics = inventory of species (distribution maps)

Systematic biogeography = spatial distribution of larger groups (phylogeography: how? when?)

Biocoenotic biogeography = distribution and dynamics of life-communities

Causal biogeographyEcological biogeography = understand the environmental factors which determine distribution (level of the individu, population)

Historical biogeography = understand present-day distribution versus origin and evolution of organisms and landscapes (level of the taxa)

Experimental biogeographyDispersal of species (e.g. larval dispersal, food availability)

Applied biogeographyIntroduction/removal of species









Stable taxonomy

Systematics

Taxonomy Phylogeny

Accurate floristics & faunistics

Intrinsic understanding of biogeography

Reduction of stochasticityin biodiversity conservation and sustainalbe usage









COP Decision VI/26

Achieve significant reduction of the current rate biodiversity loss at the global, regional and national level needed

What is significant?What is the current rate?What is biodiversity at the different levels?

What about practicalities?

Mace 2005: 32

Conservation of Biodiversitypolitics








Only when all components of biodiversity will be conserved will it be possible to safeguard key functions and benefits from ecosystems and thus achieve targets

We need meaningfullindicators to monitor trends over timeand space

(From Mace 2005)








http://www.iucn.org/programme

Conservation of Biodiversityand sustainable development

Development that meets the need of the present without compromising future generations








Thank you for your attention

1 introduction to taxonomy and biodiversity_hue

Documents

diversity of life life

unpredictable hue university

arrays of species

genetic material

genetic variants

taxa systematics

scientific discipline

particular habitats