A window onto this ancient time is provided by a little-studied fossil site near Pwerte Marnte Marnte, south of Alice Springs in central Australia. This late Oligocene site yielded the earliest-known fossils of marsupials that look similar to modern ones, as well as fossils from wholly extinct groups such as the enigmatic ilariids, which were something like a koala crossed with a wombat.

While excavating this site from 2014 to 2022, Flinders University paleontologists have found fossils from many more wonderful animals. In a pair of recently published studies, we name two of these species: a strange wombat relative and an even odder possum. Our wombat findings are published in Alcheringa: An Australasian Journal of Palaeontology, and the possum study is published in the Journal of Vertebrate Paleontology.

A toothy wombat

We discovered 35 specimens, including a partial skull and several lower jaws, from an animal that would have looked a bit like a modern wombat crossed with a marsupial lion (Thylacoleo carnifex).

Weighing in at around 50kg, it was among the largest marsupials of its time. We named it Mukupirna fortidentata.

Everything about its skull and jaws shows this animal had a pretty powerful bite. Its front teeth, for example, were large and spike-shaped, being more like those of squirrels than wombats. These would have enabled them to fracture hard foods, like tough fruits, seeds, nuts and tubers. Its molars, by comparison, were actually quite similar to those of some monkeys, such as macaques.