Diprotodon is an extinct megafauna species distantly related to wombats but the size of a small car. It is commonly (but incorrectly) thought to be Australia’s only “giant wombat.” But Griffith University researchers have shed light on a large species that does belong in the modern-day wombat family.
A team led by Associate Professor Julien Louys from Griffith’s Australian Research Centre for Human Evolution described for the first time the complete skull of this true fossil giant wombat. The skull was discovered in a Rockhampton cave in Queensland and is estimated to be around 80,000 years old.
The discovery provided unprecedented insights into the biology and appearance of these previously unknown “gentle giants.”
The cranium and mandible of the Ramsayia Magna fossil were discovered in the early 2000s. It was discovered from the rear of the front chamber of Lower Johansson’s Cave in Rockhampton. But Associate Professor Louys’s team confirmed that it belonged to a previously described but poorly known species.
Extinct Vombatidae giant wombats (roughly twice the size of modern wombats) are rarer than fossil diprotodontids. These fossil diprotodontids are frequently and incorrectly referred to as giant wombats.
According to Associate Professor Louys, this giant wombat named Ramsayia had extensive cranial sinuses. And it had not previously been reported for a wombat.
“This suggests that the wombat had a large and rounded skull for the attachment of specific. It also had powerful chewing muscles,” Louys explained. “The giant wombat also had a ‘premaxillary spine’ which indicate a large and fleshy nose.”
“We show in this paper that all true giant wombats evolved large body sizes first. Then it became highly specialised to eat different types of grasses. We also determined that this species is approximately 80,000 years old. This is the first date for this species and is much earlier than human arrival in Australia. Though we still don’t know when or why this species went extinct,” Associate Professor Louys concluded.
More information: Cranial remains of Ramsayia magnafrom the Late Pleistoceneof Australia and the evolution of gigantism in wombats(Marsupialia, Vombatidae), Papers in Palaeontology (2022). DOI: 10.1002/spp2.1475