The Los Angeles Times, USA
written by Amina Khan
Thursday October 20, 2016
Talk about a giant find. Paleontologists have dug up the fossil remains of two enormous long-necked dinosaurs in Queensland, Australia. One of them, Savannasaurus elliottorum, represents a species that’s new to science; the other specimen, Diamantinasaurus matildae, features the first skull fragments found for any Australian sauropod.
The roughly 95-million-year-old fossils, described in the journal Scientific Reports, offer clues about how these sauropod dinosaurs first arrived Down Under.
“A new dinosaur like Wade, or Savannasaurus, will allow us to work out how these dinosaurs evolved through time, how they responded to climatic changes, and also how they responded to changes in the positions of the continents as well,” lead author Stephen Poropat, a vertebrate paleontologist at the Australian Age of Dinosaurs Museum in Winton, Queensland, said in a video interview.
This specimen of Savannasaurus elliottorum (nicknamed “Wade” for Australian paleontologist Mary Wade) was discovered in 2005 by study coauthor David Elliott, who co-founded the dinosaur museum.
Elliott had been herding sheep in western Queensland when he came across a pile of fossilized bone fragments. At the time, he’d hoped that he’d discovered some kind of theropod (a group whose members include the velociraptor and Tyrannosaurus rex) but he soon realized it was a much bigger find.
“It turned out to be just as good, because it is a totally new species of sauropod — and it’s quite unlike most of the other ones around the world too,” Elliott said in a video interview. “It’s very, very different.”
Titanosaurs are the heavyweights of the long-necked sauropods; Savannasaurus elliottorum, for example, stretched to half the length of a basketball court, with a long neck and comparatively short tail. Even though it was just a medium-sized titanosaur, it was also “the most rotund sauropod we have found so far,” Poropat said in a statement.
Scientists think that the two enormous species actually managed to somehow share resources — perhaps eating different plants, or at different times of the day. But they aren’t clear on how the animals got to Australia in the first place.
They may have been able to cross from South America to Australia through Antarctica (all of which were connected at the time), but the plant record shows that there was what the study called a “sharp climatic barrier” that probably kept them out until about 105 million years ago. While much of the Earth was quite warm at that time, there were still relative cold spots that would have kept the sauropods from venturing into Antarctica.
But the dinosaurs clearly made it — and the researchers think it’s because an episode of global warming eventually helped thaw out those cold spots, which “would have enabled sauropods to disperse from South America, across Antarctica, to Australia via a set of suitable habitats,” they wrote.
The mystery of the titanosaurs has yet to be solved, however; Wade is just the fifth type of sauropod that’s ever been discovered in Australia, Poropat pointed out. Scientists say they’ll need much more fossil evidence before they can properly fill in the blanks in their history and migration patterns.
“Given the very patchy nature of the Early Cretaceous fossil record, especially in East Gondwana,” the study authors wrote, “considerable further work is required before the complex biogeographic history of the Australian Cretaceous terrestrial vertebrate fauna can be unraveled.”
The Sydney Morning Herald, Australia
written by Bridie Smith
Friday October 21, 2016
The world has a new dinosaur: a barrel-bellied giant herbivore that stood as tall as a giraffe and grazed the grasslands of what is now central-west Queensland.
While its height of up to six metres places it alongside the dainty giraffe, that's where the similarities end.
This newly discovered cretaceous creature named Savannasaurus elliottorum had stumpy legs, which it needed to support its solid frame and wide girth. Its hips alone were 1.5 metres wide.
"You could almost look at it as a long-legged, long-necked and long-tailed hippopotamus with a much smaller head," said paleontologist Stephen Poropat.
The first dinosaur bone was found by chance in March 2005 by grazier David Elliott while mustering sheep on his outback Queensland property near Winton, 177 kilometres north-west of Longreach.
It took two digs and years of painstaking work to release the bones from the clay-rich soil. A front end loader was used to scrape off the topsoil before paleontologists attempted to remove the earth surrounding the fossils. The traditional tools of choice were defeated and instead, pneumatic tools with special tips had to be called upon to remove rock from bone.
"That's why, even though this dinosaur was discovered in 2005, it hasn't been announced until now," said Dr Poropat, a research associate at the Australian Age of Dinosaurs Museum in Winton.
But unearthing the 95-million-year-old dinosaur remains was worth the wait. The find represents not only a new species of dinosaur but a new genus.
"It represents a new end point on the sauropod family tree," Dr Poropat said.
Almost a quarter of the skeleton has been retrieved - making this the third-most complete Australian dinosaur skeleton.
The largest individual fossil collected was the dinosaur's humerus, or upper arm bone, which weighs about 100 kilograms.
The bones collected include vertebrae, pelvis, shoulder and limb bones. However there are just a few neck and tail bones, leaving researchers to guess the length these body parts might have been.
Having gathered almost a quarter of the skeleton, paleontologists were able to build up a picture of what the dinosaur, which belongs to the titanosaurus group, might have looked like.
Its barrel of a belly would have housed a huge gut, where the nutrients from the vegetation it snipped off plants with its front teeth were slowly extracted. It didn't have back teeth, so was unable to chew.
"These dinosaurs may well have been like walking, fermenting vats," Dr Poropat said. "They could have retained food in their system for up to two weeks in order to extract sufficient nutritional value from their food."
Its ancestors probably came from South America - meaning the Australian dinosaur could provide an explanation as to how and when dinosaurs dispersed across the globe.
"It's a really exciting find as it sheds light on exactly how animals moved across the continents and through time," Dr Poropat said.
"And another thing the fossil record can help us answer is when the Australian fauna started to show such a unique character. It's quite possible that that process started long before Australia finally detached from Antarctica."
The discovery, as well as the identification of the first fossilsed dinosaur head bones ever found in Australia, has been outlined in the journal Scientific Reports.
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