Australia’s kangaroos and wallabies are famous for their powerful hops, but how did they develop such extraordinary legs?
New research from Flinders University has uncovered fresh clues in the fossils of one of Australia’s earliest true kangaroos, revealing how these animals first adapted to a drier, more open landscape.
The study focuses on Dorcopsoides fossilis, an ancient wallaby-like species that lived about 7 million years ago during the Late Miocene period.
Its fossils were found in the Alcoota fossil beds in the Northern Territory, one of Australia’s richest prehistoric sites.
The animal belonged to a group known as forest wallabies, or Dorcopsini, which today live only in the rainforests of New Guinea.
However, millions of years ago, their relatives also roamed Australia.
Lead researcher Dr. Isaac Kerr from Flinders University said the team analyzed the limb bones of Dorcopsoides fossilis in detail for the first time.
“Although the species was first described in 1967, it hasn’t received much attention since then,” he said. “By comparing all its fossilized limbs with those of living kangaroos and wallabies, we’ve gained new insights into how these animals evolved.”
Between 11 and 7 million years ago, central Australia’s lush rainforests gradually disappeared, replaced by drier grasslands and open woodlands.
This environmental shift sparked a burst of evolution among kangaroo ancestors, allowing them to adapt to the new terrain.
“Macropodines—the group that includes modern kangaroos and wallabies—became a dominant part of the Australian landscape during this time,” explained Dr. Kerr. “But until now, we had very little fossil evidence showing how their iconic hopping legs evolved.”
The study found that Dorcopsoides fossilis shared many traits with modern forest wallabies but also displayed features seen in gray kangaroos, such as stronger and more efficient leg bones suited for hopping. These adaptations suggest the species could move quickly and powerfully across more open ground to find food in an increasingly dry environment.
Co-author Professor Gavin Prideaux said the findings provide the earliest direct evidence that kangaroos were adapting to life in arid habitats much earlier than previously thought. “It adds a missing piece to the puzzle of how kangaroos came to dominate the Australian landscape,” he said.
As for what Dorcopsoides fossilis might have looked like, Dr. Kerr said it probably resembled a modern forest wallaby—but larger and with longer legs.
“Living forest wallabies have slightly sad, whippet-like faces and strong curved tails. Dorcopsoides was likely a tougher, long-legged version—built for the challenges of a drying world.”
