How to See What Whales Hear Biomedical imaging reveals new
insights into marine mammal ears On summer nights, if you sit
quietly at the edge of a field or watch the edges of the light
pools around street lamps, you will see bats swooping through
shadowy darkness in search of moths or other flying prey. They
detect and catch their targets through echolocation, or
biosonar, the animal equivalent—and precursor—to man-made
sonars. Bats generate signals in their nose and throat that
produce echoes, which the bats monitor to determine the size,
shape, speed, and direction of their prey, as well as any other
objects in the area. Biosonar is also how they navigate in dark
caves. Bats' large, distinctive, convoluted, and mobile ear
flaps are critical for the fine-grain acoustic analysis they do
during echolocation. Now flood that field with seawater and make
it not only dark, but profoundly deep and filled with a myriad
of exotic creatures and objects. That is the dim and complex
world in which whales live. Although w