Airdate: Sep 21, 2007
Scientist: Sheila Patek
The Lobster's Violin: Why They Do It
Spiny lobsters are particularly vulnerable during their molting stage, but uniquely equipped to ward off predators with a deafening sound.
ambience: Lobster sounds
Weâ€™re listening to a spiny lobster attempting to scare away predators. But unlike other creatures with hard outer skeletons, it uses soft body parts to produce these sounds. Weâ€™ll find out why in a moment. Iâ€™m Jim Metzner and this is Pulse of the Planet. Sheila Patek is a postdoctoral fellow at the University of California in Berkeley. She says that the spiny lobster - like other fellow arthropods - periodically sheds its outer skeleton.
â€œSo, unlike humans and mammals where you can grow by growing your internal skeleton and the outside shapes to that internal skeleton, arthropods only can grow by actually shedding their outside skeleton and building a larger one underneath it. And so they go through a process called molting where they grow a new skeleton under the old one. They shed the old one, and then thereâ€™s a larger skeleton thatâ€™s that emerges.â€
That larger skeleton takes a few days to harden, though. And while it does, these tasty crustaceans are especially vulnerable to being eaten. And so they make this loud noise to startle predators into letting go of them.
â€œSo, if your bodyâ€™s completely soft and you need to use sound to deter predators, and there are no hard parts -- itâ€™s going to be difficult. But spiny lobsters -- since they use a soft part against a smooth part -- can actually produce a deafening noise when theyâ€™re molting and when they most need to deter predators and when other structural defenses are compromised.â€
Pulse of the Planet is made possible by the National Science Foundation. I'm Jim Metzner.