Still, its auditory mechanisms have been good enough to make squid successful in an evolutionary sense. What, then, is the main purpose of the squid's hearing system?
Mooney said his work falls under the heading of "sensory biology," the study of how animals use their sensory systems to figure out the world around them. After the initial tests to see how sensitive squid are to sounds and their frequency range, he next studies will be to try to determine how important those abilities are to the animal. Do squid rely on sound to interact, migrate, communicate?
In one set of experiments Mooney will move the speakers to different positions and measure the nerves' response to see if they sense the location of that speaker.
"It's been suggested that a primary evolutionary drive behind hearing is to locate where the sound source is," he said. "If your mother is calling to you, you have to know where your mother is. If there's a predator coming you'd better darn well know where that predator is coming from so that you can get out of the way."
Another question Mooney wants to pursue is how muchif at all, squid are affected by sounds of human origin in the ocean. Loud sounds, whether a sudden explosion or continuous ship traffic, might cause squid to migrate unnaturally just to escape the racket.
Mooney also thinks squid statocysts can tell scientists a lot about how ears originated and evolved.
"Humans, fish, and lots of animals use hair cells to detect sound and movement. Their hair cell structures are similar to squid, but also quite different," said Mooney. "There is probably a basic structure which evolved millions of years ago, but vertebrates and invertebrates have taken quite different evolutionary paths since.
"By learning more about squid hearing and squid hair cells, we might learn what is important in human hearin
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Woods Hole Oceanographic Institution