Owls and cats turn out to have a not-so-charismatic rival in their much-admired ability to pinpoint a sound's origin: a sound-tracking parasitic fly.
The flies are too tiny for the usual direction-fixing physiology to work, says Andrew C. Mason of the University of Toronto at Scarborough. Yet an unusual eardrum structure allows Ormia ochracea to pinpoint a sound's source to within 2 compass degrees, Mason reported this week in New Orleans at the meeting of the Society for Neuroscience.
Neuroscientists discovered the fly's unusual ear structure several years ago. "What we're talking about now is how well it works," Mason says. "In terms of directional hearing, the flies are as good as any system ever studied."