Washington, March 26 (ANI): Reports indicate that 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.
The find sheds new light on the evolutionary history of this group of dinosaurs.
It also raises the crucial question of why it was only in the north that tyrannosaurs evolved into the giant predators like T. rex.
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," said Dr Benson.
"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," he added.
According to Dr Paul Barrett, Palaeontologist at the Natural History Museum, London and member of the research team, "The absence of tyrannosauroids from the southern continents was becoming more and more anomalous as representatives of other 'northern' dinosaur groups started to show up in the south."
"This find shows that tyrannosauroids were able to reach these areas early in their evolutionary history and also hints at the possibility that others remain to be discovered in Africa, South America and India," he said.
The bone would have come from an animal about three metres long and weighing around 80 kg, similar to a human, and would have had the large head and small arms that make tyrannosaurs so distinctive.
The newly identified dinosaur, known as NMV P186069, was much smaller than T. rex, which was 12 metres long and weighed around four tonnes.
Compared with T. rex, which lived about 70 million years ago at the end of Cretaceous period, NMV P186069 lived earlier during the Cretaceous, around 110 million years ago. (ANI)