Recent extinction surveys provide valuable data for comparative studies between prehistoric and historic extinction patterns.

Current trends in global extinction rates have been compared to former periods of mass extinction during the Paleozoic and Mesozoic geologic eras (Wilson, 1992; Jablonski, 1993; Kaufman, 1993). However, these comparisons have used predictive models for estimating current species loss and results from these models are highly variable. Use of extinction surveys to determine current global extinction rates will enable a more objective comparison between modern and pre-Holocene extinction patterns (Diamond, 1984). Thorough documentation of regional species losses, when combined with information on regional environmental changes, can be used by systematists and evolutionary biologists to test general theories about past and present extinction patterns, including large-scale mass extinctions.

AN EXAMPLE...

The putative mass extinctions of haplochromine fishes in Lake Victoria over the last 20 years is frequently cited as a potential case study in the mechanisms of extinction and subsequent, evolutionary radiation of different species groups (Seehausen, 1996; Kaufman et al., 1997).