Myers et al. [3]

Myers et al. [3] attempt to identify ``hotspots'' of biodiversity, ``areas featuring exceptional concentrations of endemic species and experiencing exceptional loss of habitat$\dots$, [because] concentrating a large proportion of conservation support on these areas would go far to stem the mass extinction of species that is now underway.'' Hotspots are identified based on two general criteria:

• Species endemism

• Degree of threat

Estimate of species endemism are based primarily on vascular plants. The specific criteria for including an area as a hotspot are:

• $\ge 5\%$ of world's vascular plant species (1500 spp.).

• Loss of 70% or more of its primary vegetation.

Data on mammals, birds, reptiles, and amphibians are to assess congruence of hotspot designations and as back-up support.