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Species Diversity. What is a Species?. Atelopus frog discovered in Suriname, June 2007. The Biological Species Concept. Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups. - Ernst Mayr. Mayr on right – in
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What is a Species? Atelopus frog discovered in Suriname, June 2007
The Biological Species Concept Species are groups of actually or potentially interbreeding natural populations, which are reproductively isolated from other such groups. - Ernst Mayr Mayr on right –in New Guinea 1928
Morphological Species Concept Species are assemblages of individuals with morphological features in common and are separable from other such assemblages by correlated morphological discontinuities in a number of features. - Davis and Heywood
How many species in genus Rubus? Red raspberry – Rubus strigosus Common blackberry – Rubus fructicosus
Red Crossbill types type 4 top, type 2 bottom
Sibling species in Gilia Gilia tricolor Gilia angelensis
Phylogenetic species concept • Species are determined by whether they are reproductively and geographically isolated from each other - thus they are considered to have branched apart - this would result in more species than we recognize today as any separated populations which do not exchange individuals would be considered to be isolated and thus separate lineages
Soil bacteria diversity – in a nutrient enrichment experiment
Seven kinds of rarity From Deborah Rabinowitz
Red Mangrove – rare – large range, narrow habitat, large populations
Pygmy Cypress – rare –small range, wide habitat, large populations
Haleakala silver sword – rare – small range, narrow habitat, large population
Beach tiger beetle – rare – small range, narrow habitat, large population
Bristle grass – rare –large range, wide habitat, small populations
Peregrine Falcon – rare –large range, wide habitat, small populations
Pacific Yew – rare –large range, narrow habitat, small populations
Malaysian tapir– rare –small range, wide habitat, small populations
Alpine Lily - rare –small range, narrow habitat, small populations
Giant Panda - rare –small range, narrow habitat, small populations
World Conservation Monitoring Centre categories for rare species • Extinct – not definitely reported in 50 years • Endangered – taxa in danger of extinction and whose survival is unlikely if current trends continue • Vulnerable – taxa likely to move into endangered category in near future if current trends continue (USFWS calls this group threatened) • Rare – taxa with small world populations that are not at present endangered or vulnerable but are at risk • Indeterminate – taxa known to be endangered, vulnerable or rare but where there is not enough information to say which category applies • Out of danger – once endangered, vulnerable or rare but now considered relatively secure • Insufficiently known – taxa that are suspected to be endangered, vulnerable or rare but not enough is known to be sure • Threatened – any taxa considered endangered, vulnerable, rare or insufficiently known • Commercially threatened – taxa not currently threatened with extinction but where all or most populations are threatened as a sustainable commercial resource
Headlines about U.S. backlog of candidate endangered species • ENDANGERED SPECIES: Obama admin confronts 'candidate species' backlog (Greenwire, 09/08/2009) • Endangered Species Backlog to Decrease Under U.S. Work Plan By William McQuillen - May 10, 2011 3:45 PM CT
Backlogged candidate species – Florida bonneted bat and streaked horned lark