National Geographic : 1961 Apr
Wi i/ yJ. Li -oln TAIL MEMBRANE CUPPED, mouth open and emitting a steady stream of beeps, the brown bat opposite swoops in on a juicy meal worm tossed to him by scientists. Like a plane snatching a nose cone fallen from space, he sweeps the meal worm into his tail scoop, then dips head to tail and takes the tidbit in his mouth (below). These rare high-speed photographs, made during studies by the Lincoln Laboratory of the Massachusetts Institute of Technology, show how a bat can catch his prey on the wing. Although scientists have been aware that the silklike tail membrane is used in the act of feeding, they assumed that the prey was caught in the bat's mouth. But the Lincoln Laboratory pictures-without exception-show brown bats while in flight fielding meal worms with their catcher's mitt tail structures. Bats, basically unchanged in the last 50 million years, navigate and hunt as man's radar- or sonar-equipped craft do: They send out high-pitched signals and evaluate the echoes to find the direction and distance of each near-by object. Free from dependence on their eyes, they can hunt at night, when insect food is plentiful and predatory birds are few. So effective has the bat's sound equipment become over millions of generations that M. I. T. scientists are studying it in search of new concepts for man's electronic devices. This insect-eating bat satisfies a voracious appetite while serving the extraordinary re search project. With the help of high-speed cameras and devices for recording and ana lyzing high-frequency sound, biophysicists hope to fathom the secret of how the bat rec ognizes his own echo in a cave teeming with thousands of other bats and their calls, and how he distinguishes food from obstacles. HS EKTACHROMESBY DAVIDCAHLANDERAND FREDERICWEBSTER, LINCOLN LABORATORY, M.I.T .