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No. 29: Sep-Oct 1993

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Porpoise Stun Gun

Just about everyone knows that some whales and porpoises have oil/wax-filled sound lenses in their foreheads. These biological lenses focus clicks and other sounds sonar-fashion ahead of the swimming animal, which then listens for echoes from prey and other targets. But what if these bursts of sound could be made very powerful -- could they be employed to stun and disorient prey?

Bits of evidence are accumulating to support the theory that some whales and porpoises actually have acoustic stun guns in their foreheads. First, there are visual observations of fish being hunted by whales and porpoises suddenly giving up flight, becoming passive, and almost asking to be snapped up by their pursuers. Second, the stomachs of whales often contain much faster and more mobile prey -- often without any teeth marks. Finally, bottlenose dolphins are known to have the capability of producing bursts of sound five orders of magnitude more intense than their usual navigating clicks. This is more than enough to kill small fish.

(Norris, Kenneth S., and Mohl, Bertel; "Can Odontocetes Debilitate Prey with Sound?" American Naturalist, 122:85, 1983.)

Comment. Here is another instance of the "problem of perfection." An existing organ of great complexity seems utterly useless of only fractionally developed. One would think that the complicated sound lenses, the muscular sound-generating tissues, and their containing structures would have to have developed in a single step in order to have any survival value.

Reference. Sperm whales also use a stun gun. See BMO10 in our Catalog: Biological Anomalies: Mammals II. For more information, visit: here.

From Science Frontiers #29, SEP-OCT 1983. � 1983-2000 William R. Corliss