A bone found on an Australian sheep farm a decade ago has proved to be that of a massive dinosaur previously unknown to science.
David Elliot was mustering sheep on his farm in Winton, central Queensland back in 2005 when he found a 30cm-long metacarpal bone sticking out of a pile of rocks.
Digging unearthed vertebra, ribs and other bones belonging to what's now been called Savannasaurus elliottorum, named for the Elliot family.
The Savannasaurus found on the Elliot farm lived about 95 million years ago, and belonged to the Titanosaur family - massive herbivorous sauropods that could grow up to 40m long.
Dr Stephen Poropat, who led the study into the find (Judy-Elliott-Australian-Age of Dinosaurs Museum of Natural History)
They also dug up the first-ever head bones to be found in Australia, which belonged to a related species - Diamantinasaurus matildae.
Together, palaeontologists from the Australian Age of Dinosaurs Museum of Natural History say Savannasaurus and Diamantinasaurus suggest titanosaurs entered Australia via Antarctica from their original home of South America about 105 million years ago.
Diamantinasaurus matildae (Travis Tischler / Australian Age of Dinosaurs Museum of Natural History)
"Titanosaurs achieved a worldwide distribution by at least 125 million years ago, suggesting that mid-Cretaceous Australian sauropods represent remnants of clades which were widespread during the Early Cretaceous," author Stephen Poropat wrote.
"These lineages would have entered Australasia via dispersal from South America, presumably across Antarctica. High latitude sauropod dispersal might have been facilitated by Albian–Turonian warming that lifted a palaeoclimatic dispersal barrier between Antarctica and South America."
The findings were announced in journal Scientific Reports.