Multitude of Species Face Climate Threat

Biologists monitoring Earth’s loss of biodiversity predict a sixth great mass extinction could be underway. Overfishing, overhunting, deforestation, development and climate could be behind some eerie changes: polar bears losing ice; whales, fish and birds adjusting migration patterns; butterflies hatching from pupae earlier, mountainside animals and plants forced to move to new heights. Policymakers press for answers from scientists about which species are in decline and the reasons – but biologists resist the pressure, reports Carl Zimmer for the New York Times. Many species have a tenuous grip on survival; any number of triggers, including climate change, could mark the end for one or another. Zimmer reports that researchers who study “climate’s effects on biodiversity are calling for conservation measures that don’t rely on impossible precision.” In the competition for habitat, humans have become an invasive species, albeit one that can document and debate the reasons for others’ decline. – YaleGlobal