Can whales plug their ears?

New York Times : Whales and other sea creatures have been shown to “decrease the sensitivity of their hearing to protect their ears from loud noise,” writes William Broad for the New York Times. Whereas humans can plug their ears with their index fingers, how whales do it has yet to be discovered. A team of researchers at the University of Hawaii has launched a preliminary study into the phenomenon to learn how killer whales hear and to try to find a way to protect that hearing. Earth’s oceans have been getting progressively noisier because of naval sonar and other equipment. Besides causing deafness, excessive noise can also disorientate whales, which then can get stranded and die (see Physics Today, November 2009, page 39 ). Although finding a way to teach animals to protect themselves from human-caused noise is not ideal, it might prove a temporary solution to a growing problem.