Carnivorous dinosaurs the size of T. rex lived in Jurassic Australia | Paleontology


Paleontologists have analyzed dinosaur footprints from 151 to 165 million years from 11 sites in southern Queensland, most of which produced large (30-50 cm length) and large theropod dinosaur footprints (length greater than 50). cm), including Australia’s largest carnivorous dinosaur footprint (79 cm long).

A reconstruction of a South Queensland Jurassic dinosaur footprint maker in front of a silhouette of the largest known Tyrannosaurus rex.  Image credit: Anthony Romilio.

A reconstruction of a Jurassic dinosaur footprint maker from South Queensland facing a silhouette of the largest Tyrannosaurus Rex. Image credit: Anthony Romilio.

“I’ve always wondered, where were the great carnivorous dinosaurs in Australia? But I think we’ve found them, right here in Queensland, “said lead author Dr. Anthony Romilio, a paleontologist at the University of Queensland School of Chemistry and Molecular Biosciences.

“The specimens of these giant dinosaurs were not fossilized bones, which are the kinds of things generally found in museums.”

“Rather, we look at the footprints, which in Australia are much more abundant.”

“These tracks were made by dinosaurs walking through the swampy forests that once occupied much of the landscape of what is now southern Queensland.”

One of the dinosaur footprints from an Oakey mine in Queensland, Australia.  Image credit: Anthony Romilio.

One of the dinosaur footprints from an Oakey mine in Queensland, Australia. Image credit: Anthony Romilio.

Dr. Romilio and his colleagues documented a total of 20 fossil dinosaur footprints and five footprints from Walloon coal measurements from the Oakey and Rosewood districts of southern Queensland.

They identified a total of 11 caterpillar mine sites (one on Oakey and ten at Rosewood), and four types of dinosaur footprints.

Large and very large tracks were more common than small ones. Most of the tracks belong to theropods, the same group of dinosaurs that includes Australovenator, Velociraptorand its modern descendants, the birds.

“Most of these footprints are around 50 to 60 cm in length, with some of the really huge tracks measuring almost 80 cm,” said Dr. Romilio.

“We estimate that these tracks were made by full-bodied carnivorous dinosaurs, some of which were up to 3m tall at the hips and probably about 10m long.”

“To put that in perspective, tyrant-saury Rex it reached about 3.25m at the hips and reached lengths of 12-13m long, but it didn’t appear until 90 million years after our Queensland giants. “

“The Queensland tracks were probably made by giant carnosaurs, the group that includes Allosaurus. “

“At the time, these were probably some of the largest predatory dinosaurs on the planet.”

The research was published in the journal. Historical biology.

_____

Anthony Romilio et al. Footprints of large theropod dinosaurs in the middle-high Jurassic Walloon (low-Callovian) measurements in southern Queensland, Australia. Historical biology, published online June 12, 2020; doi: 10.1080 / 08912963.2020.1772252