Transcript What is biodiversity? Why is it important? What threatens biodiversity

Werner Kunz
the variety of life on Earth at all its levels,
from genes to ecosystems, and the
ecological and evolutionary
processes that sustain it.
Source: ©AMNH-CBC
Genetic
component
Spatial component
Functional
component
Temporal
component
within individuals
communities
daily
within populations
ecosystems
e.g. reproductive
behavior, predation,
parasitism
between
populations
landscapes
annual
ecoregions
geological or
evolutionary
between species
biogeographic
regions
seasonal
The variation in the
nucleotides, genes,
chromosomes, or whole
genomes of organisms
Source: Human Genome Project, Department of Energy
• Classified as 1
species of killer
whale, Orcinus orca
• Genetics show might
be 3-5 species of
killer whales
• Matters whether or
not seen as
endangered
Phenotype - the physical constitution of an organism
that results from its genetic constitution (genotype) and
the action of the environment on the expression of the
genes.
Thus, phenotypic
diversity refers to
variation in the
physical traits of
the organism.
Domroese ©AMNH-CBC
Source: ©AMNH-CBC
• Species richness: the number of species present in a
given area
• Species diversity: species number weighted by
measure of relative abundance
•Many people use the term “species diversity” when
they mean species richness
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What is a species?- tps
How many species are there?
Terry Erwin says 30 million!
But we know 1.5 million
Estimated Number of Described Species
Bacteria
9,021 (0.5%)
Archaea
259 (0.01%)
Nematoda Actinopterygii
20,000 (1.1%) 23,712 (1.4%)
Other Vertebrata
27,199 (1.6%)
Other Eucarya
36,702 (2.1%)
Crustacea
38,839 (2.2%)
Other Plantae
49,530 (2.8%)
Arachnida
74,445 (4.3%)
Insecta
827,875 (47.3%)
Other invertebrate
Metazoa
82,047 (4.7%)
Fungi
100,800 (5.8%)
Stramenopiles
105,922 (6.1%)
Mollusca
117,495 (6.7%)
Angiospermae
233,885 (13.4%)
• What is an ecosystem?
• Ecosystems are a group of interacting
species both with each other and the
physical environment.
– Forests, coral reefs, grasslands, intertidal
• Why is ecosystem diversity important to us?
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coral reefs
tallgrass prairie
coastal wetlands
old-growth forest
tropical rainforest
Urban areas?
Source: Brumbaugh ©AMNH-CBC
Mangroves, Belize
Source: Harrison ©AMNH
• Species associated with:
ripening figs in a tropical
forest,
• Species clustered around a
hydrothermal vent on the
ocean floor,
• Species in the spray zone of
a waterfall,
• Species under warm stones
in the alpine zone on a
mountaintop.
Source: ©AMNH
- “a relatively large unit of land or water containing a
geographically distinct assemblage of species, natural
communities, and environmental conditions” (WWF, 1999)
Biodiversity is not
distributed evenly
across the planet:
Source: Sterling ©AMNH-CBC
Source: Kristan Hutchison,NSF: US Antarctic Program
Species diversity for most taxa is
lowest near the poles, and
increases toward the tropics,
reaching a peak in tropical rain
forests (may contain more than half
the species on Earth).
Lunde © AMNH/CBC
Adapted from Kaufman and Mallory (1986) ‘The Last Extinction’ fig 2.1
• Evolution required 10 million years or
more to attain prior levels of species
diversity
• Homo sapiens (humans) are the cause of
a sixth major extinction in history.
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causes - human induced
rate – greater
breadth of taxonomic groups affected
it can be stopped or at least slowed!
• http://vimeo.com/39048998