Caribbean Birds

Exponential Rate of Extinction

Proportion of island populations extant as a function of maximum genetic divergence of island populations of species of Lesser Antillean birds. Each symbol represents a single species. Colors correspond to the A-D distribution groups named above. The exponential curve fitted to the data (Y = e-mX) has an extinction rate (m) of 0.25 (±0.02 SE) per percentage of genetic distance (X), or about 50% per million years.