Extreme Climate Variance Sped Extinction...

Extreme Climate Variance Sped Extinction Of Local Butterfly Populations, Researchers Say: "Since 1960, population biologist Paul Ehrlich and his research group have been conducting a classic study of the population of Jasper Ridge's Bay checkerspot butterflies, subspecies Euphydryas editha bayensis. But now the biologists won't have to muck about the ridge counting insects as they have for decades to characterize rates of births, deaths, immigrations and emigrations. The last two Jasper Ridge populations went extinct in 1991 and 1998. Examining 70 years of rainfall and population data, the researchers now conclude that extreme swings in regional climate hastened extinction of the butterflies. They report their findings in the April 30 issue of the Proceedings of the National Academy of Sciences."