Scientists studying a fast-dwindling genus of colorful frogs in Central and South America say that recent global warming has combined with a spreading fungus to create a killing zone, driving many species restricted to misty mountainsides to extinction. The researchers said they had implicated widespread warming, as opposed to local variations in temperature or other conditions affecting the frogs, by finding that patterns of fungus outbreaks and species loss in widely dispersed patches of habitat were synchronized in a way that was statistically impossible to explain by chance. Climate scientists have already linked most of the recent rise in the earth’s average temperature to the buildup of greenhouse emissions from smokestacks and tailpipes. Thus the new findings, according to the researchers and some independent experts on amphibians, imply that warming driven by human activity may have already fostered outbreaks of disease and imperiled species with restricted habitats. The study, led by J. Alan Pounds, the resident biologist at the Monteverde Cloud Forest Preserve in Costa Rica, is to be published on Thursday in the journal Nature. In an accompanying commentary, two scientists not involved in the research, Andy Dobson, a Princeton University ecologist, and Andrew R. […]