Paleontologists have discovered and examined the fossilized craniodental remains of Ramsayia magna, an extinct large-bodied wombat species that lived in what is now Queensland, Australia, around 80,000 years ago.
Life reconstruction of Ramsayia magna. Image credit: Eleanor Pease.
Extinct giant wombats are members of three genera — Phascolonus, Ramsayia and Sedophascolomys — in the marsupial family Vombatidae.
These animals are broadly defined as twice the size of modern wombats, i.e. having a body mass over 70 kg.
They are considerably rarer than the fossil diprotodontids that are often popularly — and incorrectly — referred as ‘giant wombats.’
“Our discovery provides unprecedented insights into the biology and appearance of these previously little known ‘gentle giants’,” said Dr. Julien Louys, a researcher with the Australian Research Centre for Human Evolution at Griffith University.
“The extinct megafauna of Australia never ceases to amaze and intrigue not just Australians, but people all over the world.”
“Although one of the most charismatic of the giant mammals to go extinct, Diprotodon is commonly referred to as a ‘giant wombat’.”
“But this is incorrect as Diprotodon belongs to an entirely different family — equivalent to saying a hippo is just a giant pig.”
“There were however, true giant wombats. These have traditionally been poorly known, but the discovery of the most complete skull of one of these giants has provided us with an opportunity to reconstruct what this creature looked like, where and when it lived, and how the evolution of giant wombats took place in Australia.”
In their research, Dr. Louys and his colleagues examined the cranium and mandible of Ramsayia magna found in a front chamber of Lower Johansons Cave in Rockhampton, Queensland, Australia.
“This giant wombat, Ramsayia magna, had extensive cranial sinuses, which had not been previously reported for a wombat,” Dr. Louys said.
“This indicates that the wombat had a large, rounded skull for the attachment of specific and strong chewing muscles.”
“The giant wombat also possessed a premaxillary spine, an indication that it had a large, fleshy nose.”
“In this study, we show that all true giant wombats evolved large body sizes first, then individually became quite specialized to eat different types of grasses.”
“We also dated Ramsayia magna as being about 80,000 years old,” he added.
“This is the first date for this species and is much earlier than human arrival in Australia, although we still don’t know exactly when or why this species became extinct.”
A paper on the findings was published in the journal Papers In Palaeontology.
_____
Julien Louys et al. Cranial remains of Ramsayia magna from the Late Pleistocene of Australia and the evolution of gigantism in wombats (Marsupialia, Vombatidae). Papers In Palaeontology, published online December 12, 2022; doi: 10.1002/spp2.1475
Source link: https://www.sci.news/paleontology/ramsayia-magna-11472.html
