Washington, Dec 14 : A new study has established that a bizarre reversal of how feeding occurs was achieved in 210-million-year old amphibians known as plagiosaurs.

The study, conducted by Farish A. Jenkins, Jr. of Harvard University, describes new, relatively complete material of a plagiosaur called Gerrothorax pulcherrimus from the
210-million-year-old Fleming Fjord Formation of East Greenland.

Plagiosaurs were a group of flat-headed, armored amphibians unrelated to living amphibians such as frogs, salamanders and caecilians.

While a vast majority of animals use their lower jaw to chomp down on food, some animals like the Plagiosaurus, lift their heads rather than dropping the jaw for eating food.

Fossils of this group of animals have been known for a hundred years, but finds of complete specimens have been elusive.

"With their very flat, heavily armored bodies, short, stubby limbs, massive shoulder girdles and well-developed gills, these amphibians are an oddity by any measure," said Dr. Jenkins.

"The animals could throw their heads upward and backward, creating a huge mouth gape with only the slightest lowering of the lower jaw, perfect for a bottom-dwelling ambush predator," he added.

By special adaptation of the joint between the skull and first neck vertebra, the animal was able to raise its head relative to its lower jaw by as much as 50 degrees, giving it the wide gape it needed to swallow its unsuspecting prey.

"That the same species is found in Greenland as well as Western Europe and Scandinavia suggests that their unique structure was hugely successful," said Dr. Anne Warren of La Trobe University in Melbourne, Australia, a member of the team that conducted the study. (ANI)