As Long As A Basketball Court: Australia's Largest Dinosaur Confirmed

Researchers in Australia have confirmed the discovery of Australia's largest dinosaur species ever found.

Australotitan cooperensis was about 80 to 100 feet long and 16 to 21 feet tall at its hip. It weighed somewhere between 25 and 81 tons. For comparison, the Tyrannosaurus rex was about 40 feet long and 12 feet tall.

Paleontologists involved in the discovery say it's among the top 15 largest dinosaurs ever discovered in the world and ranks similar in size to the giants found in South America.

The first of the creature's fossilized bones were excavated back in 2006 and 2007, but only now, after years of analysis, have paleontologists from the Queensland Museum and Eromanga Natural History Museum been able to confirm that the bones are from the largest dinosaur in Australia.

The findings were published in the peer-reviewed journal PeerJ on Monday. Scott Hocknull, a paleontologist at the Queensland Museum, was one of the authors.

"It's taken this long because it's such a painstaking piece of work. You've got to take the bones out of the ground, you've got to prepare the fossils and then you've got to study them and compare them against all other species of dinosaurs worldwide," Hocknull told Australia's ABC News.

"In Australia, it's certainly the largest animal that's ever walked the Outback," he said. "This is huge. This is a fantastic beast. Imagine something the size of a basketball court walking around on land."

"I think it's a great, great finding," says Diego Pol, head of paleontology at the Museo Paleontológico Egidio Feruglio in Argentina, who has made similar finds but was not involved in the Australian discovery.

The dinosaur was found near the town of Eromanga in southwest Queensland in Australia's rural Outback. Researchers nicknamed it Cooper after the area near where it was found, Cooper Creek.

Australotitan lived 92 million to 96 million years ago in southwest Queensland, which at the time was still attached to Antarctica, Hocknull and Queensland Museum senior research assistant Róchelle Lawrence write.

It's part of a lineage of dinosaurs called titanosaurians, which have been found on most continents.

But Pol tells NPR that so far, all of the "super-large" titanosaurians have been found in South America's Patagonia region. "This is super-interesting because it is the first confirmation that super-large titanosaurs also inhabited in Australia," he says.

Pol says these large dinosaurs were probably living in "vast spaces," across a connected landmass including what is now South America, Antarctica and Australia.

"This means also that if we go to Antarctica and we dig into the right rocks ... most likely we will find supergiant titanosaurs that lived in Antarctica, too. So I found that super exciting."

Australotitan cooperensis is now a new species of a type of dinosaur called sauropods, which had long necks and tails, as well as four legs, and ate plants. The researchers say the new species is closely related to three other sauropods found in Australia that date to the same time period.

"We found that Australotitan was the largest in the family, followed by Wintonotitan with big hips and long legs, whilst the two smaller sauropods, Diamantinasaurus and Savannasaurus were shorter in stature and heavily-set," Hocknull said in a statement.

As part of their research, the Australian team used new 3D scanning technology to scan the bones from Australotitan and compare them to those of similar species. Both Australian and Argentinian researchers agree that the new technology has opened the doors for sharing information. Previously, paleontologists might have needed to fly across the world to look at fossils in person. Pol says the super-high resolution that now exists is "like having the real bone in your computer."

The Eromanga Natural History Museum says its team has found other dinosaur bones in the area, including ones recently discovered that need to be studied to determine if they belong to a new species.

"Discoveries like this are just the tip of the iceberg," Hocknull said in the statement. "Our ultimate goal is to find the evidence that tells the changing story of Queensland, hundreds of millions of years in the making." [Copyright 2021 NPR]