In the winter of 2007, a group of scientists exploring a cave in New York came upon a grim scene: Dozens of bats were found dead or starving, flying erratically during the day and in cold temperatures, weeks before they normally emerge from hibernation. Many of the bats, frail and lethargic, displayed a mysterious white fungus on their noses and fur.

Similar scenes in the Northeast and beyond revealed a grave threat, and in the years to follow, more than a million bats would die. Scientists studied the hibernation patterns, environs and DNA of bats to learn more about the condition. But the cause remained elusive - until October 2011, when Bucknell biology professor DeeAnn Reeder and a team of researchers at the National Wildlife Health Center in Madison, Wis., identified the fungus, Geomyces destructans, and proved it causes white-nose syndrome in otherwise healthy hibernating bats. || See full text of paper published in Nature magazine.

"For a long time, a lot of us - myself included - said fungal infections don't kill mammals, so that can't be what's killing the bats," says Reeder, an associate professor who studies the hibernation patterns of bats. "But it turns out that because of the bat's unique hibernation cycle and the nature of the fungus, it does kill them."

Although scientists have yet to find a cure, identifying a fungus as the cause of white-nose syndrome was a critical milestone. The discovery allows researchers to focus on which bats are most likely to survive and work to prevent extinction.

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