Earlier this year, a group of scientists studying golden-winged warblers in Tennessee noticed something odd: The birds had taken a sudden detour from their breeding grounds.

Analysis of the data revealed that the birds took off for Florida several days in advance of a large, severe thunderstorm system that was advancing across the Great Plains.

A new study suggests that these warblers detected the severe weather and got the heck out of the way—an ability never before documented in birds. (Read "Birds Can 'See' Earth's Magnetic Field.")

The scientists theorize the birds were tipped off by infrasound—a type of low-frequency noise—produced by the storms. Although humans can't hear infrasound, birds can, and the destructive nature of these storms may make