Tadpoles kill by supersuction - Zoology - African dwarf clawed frogs - Brief Article

Science News, Nov 16, 2002

Tadpoles of African dwarf clawed frogs catch their prey by a surprising means.

Tadpoles typically work their elaborate, jagged mouthparts over a surface, making a soup of the scrapings. Pumping movements of the mouth cavity gently pull in and filter the resulting slurry.

Researchers discovered something quite different when they turned a high-speed video camera on young Hymenochirus boettgeri not quite 3 millimeters in length. These tiny tadpoles rely on a superfast suction technique to catch prey such as minuscule water fleas, say Stephen Deban at the University of Utah in Salt Lake City and Wendy Olson of Dalhousie University in Halifax, Nova Scotia.

In the Nov. 7 Nature, the researchers report that the tadpoles track each prey individually and then suddenly extend their tube-shaped mouths to suck in the prey within 7 milliseconds. (For video, see http://socrates.berkeley.edu/~deban/hymenomovie.html.)

Although larvae of certain fish also hunt this way, the researchers were intrigued to discover that a quite different animal had evolved the same approach.--S.M.