March 26, 2010

T-Rex Ancestor Discovered in Australia

Scientists have uncovered a hip bone believed to belong to an ancestor of the Tyrannosaurus Rex in Australia, providing the first evidence that the fearsome carnivore may have lived in the southern hemisphere, according to a Thursday University of Cambridge press release.

The 30 centimeter long bone was discovered in Dinosaur Cove in Victoria by a team of researchers that included Dr. Roger Benson from the University of Cambridge's Department of Earth Science, Dr. Paul Barrett from the Natural History Museum in London, and Tom Rich of Museum Victoria in Melbourne, Australia.

It is said to have been a pubis bone that resembled a rod with a pair of expanded ends, and is believed to have come from an animal roughly 10 feet long and weighed more than 175 pounds. Despite the fact that the creature discovered, known as NMV P186069, was far smaller than the Tyrannosaurus Rex most people are familiar with, it definitely shared the same bone structure, the scientists claim.

"The bone is unambiguously identifiable as a tyrannosaur because these dinosaurs have very distinctive hip bones," Benson said in the media statement. "This is an exciting discovery because tyrannosaur fossils had only ever been found in the northern hemisphere before and some scientists thought tyrannosaurs never made it down south."

"Although we only have one bone, it shows that 110 million years ago small tyrannosaurs like ours might have been found worldwide," he added. "This find has major significance for our knowledge of how this group of dinosaurs evolved."

Benson admitted that it was "difficult to explain" why NMV P186069's family of dinosaurs only evolved into large, fearsome predators in the northern part of the world if they did, in fact, also exist in the southern reaches of the Earth.

"What we need to know now is just how diverse the early radiation of tyrannosaurs was, why they went extinct, leaving only giant-sized, short-armed species like T. rex, and how successful they might have been in the southern hemisphere. We can only answer these questions with new discoveries," he said.

The findings were published in the March 25 edition of Science, and the study was sponsored by the National Geographic Society, the Australian Research Council and Atlas Copco.


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