ScienceDaily (Mar. 26, 2010) — Scientists from Cambridge, London and Melbourne have found the first ever evidence that tyrannosaur dinosaurs existed in the southern continents. They identified a hip bone found at Dinosaur Cove in Victoria, Australia as belonging to an ancestor of Tyrannosaurus rex.
Tyrannosaurus rex. (Credit: iStockphoto)
The 30cm-long pubis bone from Dinosaur Cove looks like a rod with two expanded ends, one of which is flattened and connects to the hip and the other looks like a 'boot'.
According to Dr Roger Benson of the Department of Earth Sciences at the University of Cambridge, who identified the find: "The bone is unambiguously identifiable as a tyrannosaur because these dinosaurs have very distinctive hip bones."
The discovery lays to rest the belief held by some scientists that tyrannosaurs never made it to the southern continents.
"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. This find has major significance for our knowledge of how this group of dinosaurs evolved." says Dr Benson.
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Read more here/Leia mais aqui: Science Daily
Vol. 327. no. 5973, p. 1613
DOI: 10.1126/science.1187456
Abstract
Tyrannosaurids monopolized the apex predator niche in latest Cretaceous Laurasia. Unfortunately, the preceding 100-million-year tyrannosauroid lineage is poorly documented, and its fossil record is restricted to the northern continents. We report an Australian tyrannosauroid, represented by a pubis from the late Early Cretaceous of Victoria. This demonstrates that these extraordinarily successful predators were not restricted to Laurasia. The advanced morphology and small size of the specimen shows that tyrannosauroids with the characteristic short arms and robust skulls probably had a global distribution in the Early Cretaceous. Thus, a potentiallycosmopolitan grade of small tyrannosauroids with a tyrannosaurid-like body plan preceded the Late Cretaceous rise of the colossal tyrannosaurids.
1 Department of Earth Sciences, University of Cambridge, Cambridge CB2 3EQ, UK.
2 Department of Palaeontology, Natural History Museum, London SW7 5BD, UK.
3 Palaeontology Department, Museum Victoria, Melbourne, Victoria 3000, Australia.
4 School of Geosciences, Monash University, Clayton, Victoria 3800, Australia.
* To whom correspondence should be addressed. E-mail: rbb27@cam.ac.uk
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