How is Biodiversity Distributed? -...

How is Biodiversity Distributed?

Brook Milligan

Department of BiologyNew Mexico State University

Las Cruces, New Mexico 88003brook@nmsu.edu

Fall 2009

Brook Milligan How is Biodiversity Distributed?

Goal: Understanding Distribution of Biodiversity

If biodiversity can be quantified, . . .

How many known species are there on Earth?

How many actual species are there on Earth?

How are the species distributed across taxa?

How is biodiversity distributed across the Earth?

Brook Milligan How is Biodiversity Distributed?

Known Species on Earth

Total: 1.5–2× 106 species

Insecta: 751× 103 species

Planta: 250,000 species

Aves: 9,000 species

Mammalia: 4,000 species

Brook Milligan How is Biodiversity Distributed?

Known Species on Earth

Total: 1.5–2× 106 species

Insecta: 751× 103 species

Planta: 250,000 species

Aves: 9,000 species

Mammalia: 4,000 species

Brook Milligan How is Biodiversity Distributed?

Known Species on Earth

Total: 1.5–2× 106 species

Insecta: 751× 103 species

Planta: 250,000 species

Aves: 9,000 species

Mammalia: 4,000 species

Brook Milligan How is Biodiversity Distributed?

Species Scape

Brook Milligan How is Biodiversity Distributed?

So, how many species are there on Earth?

Highly uncertain, especially in some taxonomic groups

How can we find out?

Requirements for effective estimation

Brook Milligan How is Biodiversity Distributed?

Brook Milligan How is Biodiversity Distributed?

Brook Milligan How is Biodiversity Distributed?

Brook Milligan How is Biodiversity Distributed?

Brook Milligan How is Biodiversity Distributed?

Brook Milligan How is Biodiversity Distributed?

Regions of High Diversity

Tropical diversity

tropical rain forestscoral reefslarge tropical lakesdeep sea

Temperate diversityPlant diversity: Mediterranean climate regions

Mediterranean BasinCaliforniacentral ChileCape region of South Africa

Brook Milligan How is Biodiversity Distributed?

Factors Influencing Diversity

Climate and the environment

Topography, geological age, habitat size

Latitude

Taxon

Brook Milligan How is Biodiversity Distributed?