A recent study reports that giant dinosaurs known as titanosaurs might have trekked across Antarctica to get to Australia from South America.

The research is based on new sauropod fossils found in Australia, which are between 95 and 98 million years old. The fossil’s age indicates they made the long trip during the Cretaceous. Sauropods are a group of herbivorous long-necked dinosaurs. They include the largest land animals that have ever existed on Earth, and, according to the study, they trekked a long way to get to Australia. Among the fossils, scientist discovered a new species of Sauropods: The “Savannasaurus eliottorum.”

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An accidental find led to a complete skeleton of its kind unearthed from the continent. Image Credit: Travis Tischler/ Australian Age Of Dinosaurs Museum of Natural History

The study suggests that these large beasts, including titanosaurs, are much younger than the first type of dinosaurs that first walk Australia. The new fossils are believed to have been in the country-continent about a hundred million years ago.

The fossils allowed scientists to construct a new sauropod family tree which points to the theory that the titanic animals traveled from South America to Australia by land during the Cretacious. Back then, the continents were almost in the position they currently are.

The sauropods are believed to have survived the Antarctica because of a natural global warming that was taking place when the group trekked from one continent to another.

The ancient bones tell a great story, but to know it; people had to work hard for years. The Savannasaurus’ bones were found in 2005. They were located, as the name of the animal suggests, in a grassland, in eastern Australia and discovered by a dinosaurs enthusiasts.

David Elliot, an Australian sheep farmer, was the first person to locate the bones that unfortunately were encased in rock harder than concrete. It took numerous volunteers to liberate the bones from the rocks to start studying them.This is the main reason why the study was made public in 2016. The document was published in the journal Nature on October, 20.

Elliot’s passion for dinosaurs has revitalized the study of Australian fossils. Additionally,  his love for the prehistoric animals led him to found the Australian Age of Dinosaurs Museum. Regarding the study, he said that although it took them a long time to described the fossils, it is an exciting time. The dinosaurs found are unlike other sauropods around the world.

Without the fossils discovered by Elliot, it would have been impossible to come to the conclusion that the titanic dinosaurs made an Antarctic trek. Now the bones represent an important addition to the Australia’s fossil record and the sauropod fossils that have been few in the continent.

Stephen Poropat, the study author and paleontologist with the Australian Age of Dinosaurs Museum in  Winton, Queensland, Australia, said:  

“By plotting the evolution of these sauropods against changes in the positions of the continents, we’ve possibly been able to constrain when these titanosaurs migrated,”

The remains are almost complete, including the first sauropod skull ever found in Australia. It belonged to a sauropod species called “Diamantinasaurus matildae.”

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Map of Queensland, northeast Australia, showing the distribution of Cretaceous outcrop. Image Credit: Nature

Savannasaurus: a unique sauropod with different bone evolution

Savannasaurus had hollow bones and air sacs throughout its body, like all sauropods. The bone form is an evolutionary attempt to make the long-necked dinosaurs lighter. The new sauropod species probably was 20 feet tall, and it could have weighed between 15 to 20 tons. According to Poropat, these dinosaurs were like “a giant fermenting vat and a long-necked, long-legged hippo.”

What is most important about Savannasaurus is that they are unique among sauropods. Co-author Paul Upchurch, a University College London paleobiologist and sauropod expert, says that the new member of the sauropod family has a different bone structure.

For instance, it has extremely wide hips, which is believed to have given the dinosaur more stability and flexibility when exploring in interior environments. Poropat adds that the large animal’s belly should have been enormous. A huge belly probably means that the species had a convoluted and extensive digestive system, which allowed it to absorb more nutrients from its food than other sauropods.

Savannasaurus’ pelvises are also different, and Upchurch found peculiar that some parts of the bones were “paper-thin.” But there is a significant amount of work ahead of the study team before completely understand the recent Australian fossils and their trip to the continent.

Australia has not a long history of fossil finding, and dinosaurs tracks are blurry on the continent

Australia has been a “black hole” when it comes to dinosaurs, according to Stephen Brusatte, a University of Edinburgh paleontologist. Brusatte said in an email statement that the discovery of the Savannasaurus gives the paleontology society “a nice glimpse”  of what the titanic beasts looked like when they existed.

He also added that because of scientists’ little knowledge about the dinosaurs that lived in Australia has made even more challenging to study how the prehistoric animals moved around the Earth. (Brusatte is not part of the study team.)

Future research regarding the new fossils includes Mr. Poropat and his colleagues doubling back and comprehensively describing the new fossils to confirm the Savannasaurus assignments. The team is already working on the extended sauropod family tree to help scientist to understand better how they lived and how they died.

Source: Nature