Triple Fossil Find Puts Australia Back On The Dinosaur Map

Scientists have discovered three new species of Australian dinosaur discovered in a prehistoric billabong in Western Queensland.

Reporting on July 3 in the open-access, peer-reviewed journal, PLoS ONE, Scott Hocknull and colleagues at the Queensland Museum and the Australian Age of Dinosaurs Museum of Natural History describe the fossils of three new mid-Cretaceous dinosaurs from the Winton Formation in eastern Australia: two giant, herbivorous sauropods and one carnivorous theropod, all of which are to be unveiled in Queensland on July 3. The three fossils add to our knowledge of the Australian dinosaurian record, which is crucial for the understanding of the global paleobiogeography of dinosaurian groups.

Australia’s dinosaurian fossil record is extremely poor, compared with that of other similar-sized continents, such as South America and Africa. However, the mid-Cretaceous Winton Formation in central western Queensland has, in recent years, yielded numerous fossil sites with huge potential for the discovery of new dinosaurian taxa. Between 2006 and 2009, extensive excavations have yielded many well-preserved dinosaur fossils, as well as the remains of other contemporaneous fauna.

In a single, comprehensive, publication, Hocknull and colleagues describe the remains of three individual dinosaur skeletons, found during joint Australian Age of Dinosaurs Museum and Queensland Museum digs in two different sites in the Winton Formation. They represent three new genera and species of dinosaur: two giant herbivorous sauropods and a carnivorous theropod.

The carnivore, named by the authors on the paper Australovenator wintonensis (nicknamed “Banjo”) is the most complete meat-eating dinosaur found in Australia, to date and sheds light on the ancestry of the largest-ever meat-eating dinosaurs, the carcharodontosaurs, a group of dinosaurs that became gigantic, like Giganotosaurus.

“The cheetah of his time, Banjo was light and agile,” said lead author Scott Hocknull. “He could run down most prey with ease over open ground. His most distinguishing feature was three large slashing claws on each hand. Unlike some theropods that have small arms (think T. rex), Banjo was different; his arms were a primary weapon.

“He’s Australia's answer to Velociraptor, but many times bigger and more terrifying.”

The skeleton of Australovenator solves a 28-year-old mystery surrounding an ankle bone found in Victoria, which was originally classified as a dwarf Allosaurus, although this classification remained controversial until the discovery of Australovenator—the researchers are now able to confirm that the ankle bone belonged to the lineage that led to Australovenator.

The two plant-eating theropods, named Witonotitan wattsi (“Clancy”) and Diamantinasaurus matildae (“Matilda”), are different kinds of titanosaur (the largest type of dinosaur ever to have lived). While Witonotitan represents a tall, gracile animal, which might have fitted into a giraffe-like niche, the stocky, solid Diamantinasaurus represents a more hippo-like species.

All three dinosaurs are nicknamed after characters from a world-famous, Australian poet. Banjo Patterson composed Waltzing Matilda in 1885 in Winton, where the song was also first performed (and where the fossils were discovered). Waltzing Matilda is now considered to be Australia’s national song.

In a quirky twist of fate, the song Waltzing Matilda describes the unfortunate demise of a swag-man, who steals a jumbuck (sheep) but is driven to leap into a billabong (an Australian word for a small oxbow lake) to avoid being captured by the police. He ends up drowning in the billabong alongside the stolen sheep.

Banjo and Matilda were found buried together in what turns out to be a 98-million-year-old billabong. Whether they died together or got stuck in the mud together remains a mystery; however, echoing the song, both predator and possible prey met their end at the bottom of a billabong, 98 million years ago. This shows that processes that were working in the area over the last 98 million years are still there today. “Billabongs are a built-in part of the Australian mind,” said Hocknull, “because we associate them with mystery, ghosts and monsters.”

The finding and documentation of the fossils was a 100% Australian effort. Both Matilda and Banjo were prepared by Australian Age of Dinosaurs Museum thanks to thousands of hours of volunteer work and philanthropy.

“This is the only place in Australia where you can come off the street and be taught to be a palaeontologist and find, excavate and prepare your own part of Australian natural history,” said Hocknull. The dinosaurs will now be part of a museum collection and this effort will enable future generations of scientists to be involved in a new wave of dinosaur discoveries and to bring the general public in touch with their own natural heritage.”

This collaborative effort links closely with PLoS ONE’s philosophy of making science freely accessible to the general public. “One of my major motivations for submitting to PLoS ONE was the fact that my research will reach a much wider community, including the hundreds of volunteers and public who gave their time and money to the development of natural history collections,” said Hocknull. “They are the backbone of our work (excuse the pun) and they usually never get to see their final product because they rarely subscribe to scientific journals.”

All three new taxa, along with some fragmentary remains from other taxa, indicate a diverse Early Cretaceous sauropod and theropod fauna in Australia, and the finds will help provide a better understanding of the Australian dinosaurian record, which is, in turn, crucial for the understanding of the global palaeobiogeography of dinosaurian groups.

The authors agree that even though hundreds of bones have already been found at the site, these fossils are just the tip of the iceberg. “Many hundreds more fossils from this dig await preparation and there is much more material left to excavate,” they said. Australian Age of Dinosaurs Museum and Queensland Museum staff and volunteers will continue to dig at this and other sites in 2010.

The fossils will be unveiled at the Australian Age of Dinosaurs Museum of Natural History in Queensland, Australia, July 3 by Anna Bligh, the Premier of Queensland. Stage 1 of the museum, a non-profit, volunteer-driven, science initiative that aims to bring Australian dinosaurs to the world, will also be opened by Ms Bligh on July 3.