Science News Archive

Jaws II - The Moray Returns

Scientists have discovered how Moray eels manage to swallow things nearly as large as themselves - they have a second set of teeth in their throat, called pharyngeal jaws, that jump forwards and grab whatever's in the mouth and drag it down the animal's oesophagus. Rita Mehta, from UC Davis, made the dicovery by capturing fast camera footage of morays as they dined, and then confirmed the findings with fluoroscopy, the eel-equivalent of a barium swallow. "These creatures have evolved this intriguing adaptation because their large body size makes them dependent on eating other large creatures like fish and cephalopods" explains Mehta. "Most fish use suction to pull prey into their mouths and down their throats; but larger prey can more easily escape, and since morays live in crevices and holes, they would not be able to expand their heads to create the suction they needed to capture things". Other long thin creatures, like snakes, use alternative methods to swallow large prey, such as dislocating their jaw and racheting it left to right to squeeze things in. But this is the first time that an alternative to hydraulic has been seen in fish.

9th Sep 2007