Scientists said Monday a new fossil discovery suggested Australia's dinosaurs were cosmopolitan globe-trotters, unlike the "unique weirdos" of its current wildlife.
Palaeontologist Erich Fitzgerald said an ankle bone fossil found 87 kilometres from Melbourne indicated that meat-eating dinosaurs known as ceratosaurs lived in what is now Australia some 125 million years ago.
He said the finding suggested that back then Australia had the same large, well-known predators such as tyrannosaurs and allosaurs, which are found around the world.
"The dinosaurs we see here are not unique weirdos like modern koalas and kangaroos on a global scale," Fitzgerald told AFP.
"Contrary to the modern animals we see in Australia, these meat-eating dinosaurs in Australia represent globe-trotting groups which spread out across the world before the continents began to separate.
"We've got representatives of groups that are actually found everywhere else. We really have this melting pot... where it was really a cosmopolitan bunch of dinosaurs which called Australia home 125 million years ago."
The ceratosaur was a relatively small, meat-eating dinosaur which grew to be one to two metres high and could be as long as three metres.
The discovery, announced in the journal Naturwissenschaften, adds to the picture about dinosaurs in eastern Gondwana, the continent which broke into Australia, Antarctica and India between 80 and 130 million years ago.
"It had been thought that isolation played a lead role in the formation of Australia's dinosaur fauna," said Fitzgerald, a Museum Victoria palaeontologist.
"But the ceratosaur and other new discoveries show that several dinosaur groups were here. These dinosaur lineages date back to the Jurassic, 170 million years ago, when dinosaurs could walk between any two continents.
"Until now, this group of dinosaurs has been strangely absent from Australia, but now at last we know they were here — confirming their global distribution."
Fitzgerald added the ankle bone, found near the coastal town of San Remo by an amateur palaeontologist in 2006, was only six centimetres wide but was of great significance in understanding dinosaurs in Australia.
"Apart from Antarctica, Australia has the world's most poorly-known dinosaur record," he said, adding that even "tantalising fragments" can end up providing researchers with a wealth of information.