Ecosystem diversity Ecosystem diversity = the number and variety of ecosystems Also encompasses differing communities and habitats Rapid vegetation change and varying landscapes within an ecosystem promote higher levels of biodiversity
Some groups contain more species than others Species are not evenly distributed among taxonomic groups -Insects predominate over all other life-forms -40% of all insects are beetles Groups accumulate species by -Adaptive radiation -Allopatric & Sympatric speciation -Low rates of extinction
What is the Edge effect and how does it affect biodiversity? The cowbird and the woodthrush Effects on Tropical Forests http://wps.prenhall.com/wps/media/objects/489/501463/CDA52_ 2/CDA52_2a/CDA52_2a.htm
Ecosystems integrate spatially Ecosystems vary greatly in size The term “ecosystem” is most often applied to self-contained systems of moderate geographic extent Adjacent ecosystems may share components and interact Ecotones = transitional zones between two ecosystems in which elements of different ecosystems mix
Two Protection Approaches Single Species Approach –Protection efforts and funds are aimed at protecting one species –Usually protects charismatic species. –May take funds away from projects that might better benefit all species. Ecosystem Approach –Protection efforts and funds are aimed at protecting entire ecosystems –May protect a larger amount of less charismatic species at the expense of one charismatic species.
ESA Protection Steps 1.Petition to the US Fish and Wildlife Service (USFWS) or the US National Marine fisheries Service (USNMFS) 2.USFWS or USNMFS decides whether the data shows protection is “warranted”. (90 days) 3.USFWS or USNMFS conducts its own “status review” (One Year) 4.If approved and added to the endangered species list, the agencies –Restrict “taking”—harassing, harming, trapping, transporting, or selling a species –Develop and carryout recovery plans by working with property owners and public interests to identify and protect “critical habitat”