Paleontologists from the Museums Victoria Research Institute and elsewhere have unearthed a nearly 50,000-year-old skeleton of Simosthenurus occidentalis — a species of giant short-faced kangaroo that lived in Australia until about 42,000 years ago — in Nightshade Cave in Gunaikurnai Country, north of the township of Buchan in eastern Victoria, Australia.
Thank you for reading this post, don't forget to subscribe!“Short-faced (sthenurine) kangaroos appear in Australia’s fossil record from 10 to 15 million years ago, as widespread rainforests began to give way to drier habitats,” said Dr. Tim Ziegler, collection manager at the Museums Victoria Research Institute.
“They became particularly diverse during the shift toward our current arid climate in the later part of the Pleistocene epoch, from around 500,000 years ago.”
“But in a pulse of extinction around 45,000 years ago, they vanished across the continent, along with up to 85% of Australia’s megafauna.”
The 49,400-year-old skeleton of the giant short-faced kangaroo Simosthenurus occidentalis was discovered in Nightshade Cave in Victoria.
The animal’s skull was spotted by a local caving group in 2011. Only ten years later, the individual’s postcranial skeleton was recovered by the professional paleontologists.
“The skull had a deep muzzle, with robust jaws and teeth that marked it as a short-faced kangaroo,” Dr. Ziegler explained.
“Behind it were more bones. It was a marvel to see vertebrae, shoulders and hips, limbs and a narrow ribcage: many of the bones were wholly undisturbed and still in their original positions. This was a single animal, not a random scattering of bones. It felt like a fossil holy grail.”
Simosthenurus occidentalis. Image credit: Nellie Pease / ARC CoE CABAH / CC BY-SA 4.0 Deed.
According to the team, the find belonged to a juvenile Simosthenurus occidentalis.
“That it is a juvenile rather than adult kangaroo further distinguishes it from other examples of the species,” Dr. Ziegler said.
“Its teeth show little wear, its skull bones are still unfused, and its limb ends had not yet joined.”
“From the size of its limbs, we estimate it weighed around 80 kg — as much as an average person — but might have grown half as large again had it reached adulthood.”
Comprising 150 preserved bones, the specimen is the most complete fossil skeleton found in a Victorian cave to date.
This fossil, along with others from Nightshade Cave, is now housed and cared for in perpetuity at Melbourne Museum.
“The skeleton we found has a uniquely complete vertebral column, providing new insights we couldn’t get from isolated bones,” Dr. Ziegler said
“With the benefit of detailed 3D models, this near-complete skeleton can also be studied from anywhere in the world.”
“The key idea under investigation is whether sthenurine kangaroos walked with a striding gait, rather than hopped.”
