Wednesday, 21 March 2007

Crikey! Jurassic croc discovered

An ancient sea-going crocodile from the Jurassic era has been discovered in the rocks of a mountain range in the U.S.

Fossilised remains were found imbedded in Jurassic rock in the Blue Mountains in eastern Oregon. About 50% of a 6- to 8- foot reptile was recovered, including long, needlepoint teeth.

The reptile is believed to have been a crocodile-like creature, except that it had a fish tail. It is believed to be from the species Thalottosucia, which is a predator that would have been common around much of the world about 142 to 208 million years ago.

An artist's illustration of what the Jurassic-age crocodile may have looked like in the water - John Hughes

Fossils similar to the Oregon crocodile appear today in many areas around South China, according to University of Oregon geologist William Orr, who also advises the North American Research Group (NARG) that made the discovery.

Orr expects the reptile to have lived in a tropical costal environment somewhere in the western Pacific, probably in area from Japan to East Timor. The remains in Oregon are believed to have migrated eastward in rock by continental drift.

Based on locations where fossils have been found, scientists have theorized that Thalattosuchians may have moved from semi-aquatic freshwater reptiles into fully ocean forms.

The reptiles' short stubby legs would have allowed them to move about land, where they may have laid eggs. But also, the creatures may have had webbed feet, which, in combination with the fish-like tail, would have made them rapid swimmers, allowing them to hunt along the surface of aquatic environments, scientists have theorized.

More information is available from the University of Oregon’s press release.

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