Climate change could trigger boom-and-bust population cycles making animal species more vulnerable to extinction. Environmental conditions that produce abundant supplies of food and stimulate population booms set the stage for population crashes that occur when several good years in a row are followed by a bad year. “It’s almost paradoxical, because you’d think a large population would be better off, but it turns out they’re more vulnerable to a drop in resources,” says Christopher C. Wilmers of the University of California, Santa Cruz, as reported by EurekAlert. Wilmers’ powerful new mathematical model evaluates how climate and resources interact with populations, finding that dramatic population fluctuations make species more vulnerable to extinction due to disease, inbreeding, and other causes, with each crash reducing the genetic diversity of a species, lowering its ability to adapt and making it more prone to extinction. —Julia Whitty
