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Meet ‘Cooper,’ the largest Aussie dinosaur

Scott Hocknull and Robyn Mackenzie pose with a 3-D reconstruction and the humerus bone of “Cooper,” a new species of dinosaur discovered in Queensland, Australia. (Eromanga Natural History Museum/Reuters)
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A dinosaur skeleton nicknamed “Cooper” — the largest ever found in Australia, with a body spanning nearly 100 feet — belongs to a newly discovered species, according to experts.

Also known as Australotitan cooperensis, or Australotitan for short, the basketball-court-length dinosaur’s remains were first found and excavated in the outback of Queensland in 2006 and 2007. The animal’s English name — “Southern Titan of the Cooper,” or Cooper — is a homage to the freshwater Cooper Creek close to where it was found.

Scientists in Australia say Cooper is an entirely newly discovered species of long-necked titanosaur sauropod dinosaur that lived between 92 and 96 million years ago. Cooper grazed on plants, weighed about 70 tons, reached nearly 98 feet in length and stood as high as a two-story building.

For more than 15 years, experts from the Queensland Museum and Eromanga Natural History Museum, along with other paleontologists, geologists and volunteers, worked to identify the findings and confirm it was indeed a unique species. That involved painstaking work excavating the fragile remains and removing the large rock in which the bones had been entombed.

Scientists next used new technologies to create 3-D scans of the bones so they could be compared to other species kept in far-away museums.

“The discovery of Australia’s largest dinosaur was totally unexpected and, as it has turned out, was just the tip of the iceberg of numerous significant dinosaur discoveries that has come since and continue to be made,” Eromanga Natural History Museum and field paleontologist Robyn Mackenzie told Australian media.

“These dinosaur discoveries have opened a whole new world, not just to our family, but to people throughout Australia,” she continued. “It has been the most enriching journey.”

The journey began fortuitously for Mackenzie in 2004, when her son, Sandy, found a rock reminiscent of a fossil on their family property near Cooper Creek. The family had long thought that there could be dinosaurs below their home — and the discovery set them on a mission to find out. They’ve since built a foundation and a museum in the area.

Queensland’s outback is made up of largely flat plains, which can make finding dinosaur remains trickier than in mountainous or other terrains where earth more easily erodes and fossils are exposed.

Paleontologists previously identified three other sauropod dinosaurs in Australia. Cooper is closely related to them, though it’s not clear if any of the species overlapped in place or time. Most other dinosaurs of Cooper’s massive caliber have been found in South America.

Cooper “is the first Australian dinosaur to be able to join the elite group of dinosaur giants that until now have mostly been found in South America,” Mackenzie said. “These are the largest dinosaurs that ever walked on Earth and based on the preserved limb size comparisons, this new titanosaur is estimated to be in the top five largest in the world.”