Home / Science / New wallaby-sized dinosaur identified from fossils found along the Victorian coast – Science News

New wallaby-sized dinosaur identified from fossils found along the Victorian coast – Science News



Fossilized jawbones found in rocks along Victoria's Gippsland coast have been identified as belonging to a new species of plant-eating dinosaur the size of a wallaby that would have roamed the country between Australia and Antarctica.

Key points

  • Galleonosaurus dorisae was identified from an analysis of five 125-million-year-old jawbones
  • This is the first new dinosaur named in the Gippsland area for 20 years
  • The fossils help piece together the diversity of dinosaurs in southern Australia and where they fit into the global picture Galleonosaurus dorisae is just the second dinosaur of its type to be identified from the 1
    25 million-year-old rock platforms south-east of Melbourne – and the fifth from along the Victorian coastline. [19659007] Millions of years ago, this area was a lushly forested rift valley with a 4,000-km chain of volcanoes to the east, said palaeontologist Matthew Herne of the University of New England.

    "It's a lost world. None of this is now available or evident except for fossils, and the only place we can actually access these fossils is along the southern coast of Victoria, "Dr. Herne said.

    Dr Herne and colleagues have spent the past 10 years carefully analyzing fossils collected from the flat rocks area near Inverloch by other palaeontologists and volunteers from the dinosaur dreaming team. [Ifyouactuallyholdup[the largest jawbone] upside down, it looks the part of a galleon sailing ship so the name was kind of there. from the get go. "

Analysis of the fossils, published in the Journal of Palaeontology, indicate Galleonosaurus belonged to a large group of herbivores known as ornithic – or bird – hipped – dinosaurs.

As the name suggests, these dinosaurs have hips that resemble modern birds, although the two groups are not directly related.

"We know it would have been a two-legged, quite agile plant-eating dinosaur," Dr. Herne said. s Period there were several species of small bird-hipped dinosaurs living around the edges of lakes and large rivers in the area.

"It seems that Galleonosaurus was probably closely related to as many as four or five other species that look A little bit similar and were similar sizes, "Dr. Herne said.

" But we can tell differently the anatomy of the jaws and the teeth. "

The team used 3D micro-CT Scanning techniques to analyze tooth, and five different sizes, ranging from 60-40 millimeters in length, and tooth.

"Micro CT allow us to actually peer inside the actual jaw and look at the structures internally," Dr Herne said.

The different sizes in The dinosaurs were at different stages of development.

Jawbones were different to those of Qantassaurus intrepidus – the only other small plant-eating dinosaur of this type from the Gippsland region identified 20 years ago.

"Qantassaurus seems to be have a much more beefy, robust jaw. It seems like Galleonosaurus … had more fine facial features. "

" "This kind of suggest that we had different ornithopods that were possibly feeding on different types of plant material and might have different parts of the environment." or Galleonosaurus skull ” class=”lazyload” data-expand=”0″/>

Galleonosaurus was more than other species found in the area.

(Supplement: Matt Herne) Model of Galleonosaurus skull ” class=”lazyload” data-expand=”0″/>

Galleonosaurus was more than other species found in the area. 19659022] The newly described dinosaur is also around 12 million years older than fossils of another small herbivorous diluicursor pickering, which was found in the 113 million-year-old rocks along the coast of the Otway region to the south-west or Melbourne. 19659007] "The interesting thing about the whole coastline is it gives us a decent age range over quite a long period," Dr Herne said.

Piecing together Australia's dinosaur story

Piecing together the story of Australia's dinosaurs has been challenging, said University of Queensland palaeontologist Steve Salisbury, who was not directly involved in this study.

"One of the issues has been found in fossils of these kinds of dinosaurs found in Victoria on both sides of the coast since the late 80s but almost all the fossils that have been found, are couple of specimens, are isolated bits and pieces, "Dr. Salisbury said.

He said the discovery was a major step towards understanding the diversity of ornithic dinosaurs in southern A Australia

"Within two areas we have potentially got two different faunas that are separated by time," said Salisbury.

It can also help scientists understand where Australia's dinosaurs fit into the global picture.

Australia, Antarctica and South America were once in a supercontinent known as Gondwana, which broke apart over time.

When Galleonosaurus was roaming the land, Antarctica and Australia were joined together and connected to New Zealand via a massive volcanic ridge to the east.

"We should see the same sorts or dinosaurs roaming across Australia, Antarctica and South America, but even what we have seen we have not been able to demonstrate from the fossils, "Dr. Salisbury said.

" And we're just starting to The discovery would not have been possible without the Dinosaur Dreaming team, he added.

"Every year there is a dedicated team of volunteers that go down there and they crack out bits of rock and split them into tiny bits looking for all these pieces and without that none of this would have emerged. "

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