Sept 6 : Morays have two sets of jaws much like aliens in sci-fi movies, according to a new study by an Indian origin biologist from the University of California, Davis.

After seizing prey with the jaws, the moray uses a second set of jaws located deep within its throat to reach forward and grab the food and carry is back to the oesophagus for swallowing.

“This is really an amazing innovation for feeding behaviour for fishes in general,” said Rita Mehta, a postdoctoral researcher in the Section of Evolution and Ecology at UC Davis.

Mehta used a high-speed digital camera to film eels feeding in the laboratory, capturing the rapid movement of these secondary pharyngeal jaws.

She also used X-ray and other imaging equipment at the UC Davis School of Veterinary Medicine to work out how the jaws could move.

Most fish feed by suction. When it comes upon food or prey, the fish rapidly expands its mouth cavity, sucking in water and the food with it. Some fish feed by overtaking prey with their mouth open or grabbing it in their jaws, but most of those fish then use suction to move the food from the mouth to the oesophagus.

But, moray eels have little ability to generate suction through their mouths. Instead, they first grasp food with their powerful, toothsome outer jaws. Then the pharyngeal jaws, armed with large, curved teeth, reach forward and seize it.

At the same time, the outer jaws release the prey and the pharyngeal jaws bring it back for swallowing. The whole process takes just fractions of a second.

Peter Wainwright, professor of evolution and ecology at UC Davis and co-author on the paper said, while other fish were also known to have pharyngeal jaws that could grind or crush food, but they were “nothing this spectacular”.

“Only the moray eel seems to have a second, mobile set of jaws that can reach forward and grab prey. At rest, the pharyngeal jaws sit behind the eel’s skull,” the researchers wrote in their study in the Sept. 6 issue of the journal Nature.

“When they reach forward, they move almost the length of the animal’s skull, but do not protrude beyond the powerful outer jaws. The arrangement means that if the eel can sink in a few teeth to hold its prey, it can secure its meal with the pharyngeal jaws,” the study added. (ANI)