National Geographic : 1999 Jan
EHBY DIETMARNILL FROZEN BATS ... The pitch black of a Panama nian night is pierced by an array of flashes as Elisabeth Kalko studies foraging bats on Barro Colorado Island. High-speed images (top) by her team matched to taped ultrasound recordings show how bats use echolocation for various tasks, such as detecting prey and measur ing distances. "We have also identified species by their calls," Kalko says, "including high-flying bats that would otherwise go undetected." ... AND REALLY BIG RATS A rodent phobic's nightmare is a dream for Jim Patton, surrounded by rats, bats, and other small mammals he brought back from northern Vietnam. An evolutionary biologist at the University of California, Berkeley, Patton's numerous Society grants have helped him study small mammals around the world. "On a Geographic-sponsored expedition to western Brazil in 1991," he says, "20 percent of the small mammals we found were new to science."