Modern kangaroos with their hopping gaits are unusual considering all the kangaroos that ever lived.
Illustration of a Protemnodon with a four-legged gait. (Image Credit: Stanton F Fink).
New Delhi: Researchers from the University of Bristol have discovered that a type of extinct Kangaroo that became extinct around ten thousand years ago, was a poor hopper. Previously, scientists assumed that the large kangaroo known as Protemnodon was a hopper, considering the gaits of modern kangaroos. The new research indicates that they were primarily quadrapedal, using all four legs to move around, unlike their modern relatives. The study supports previous research that had indicated that the ankle bones of the Protemnodon were unsuitable for hopping.
Thrilled to announce the publication of the second paper from my MSc research! In this paper we look at macropod limb proportions to determine the probable locomotor mode of Protemnodon, and I present a new restoration of the genus based on the findings (link to follow)… pic.twitter.com/5s6jBSBvuV
— Billie Jones (@PalaeoBillology) June 25, 2024
A paper describing the findings has been published in the Journal of Mammalian Evolution. Lead author Billie Jones says, “There had been some speculation in a graduate thesis from the University of Uppsala that it might have been more quadrupedal in its habits compared to living kangaroos. This new paper draws on a couple of previous quantitative studies that looked at the anatomy of the humerus (upper arm bone) in a diversity of mammals, and concluded that Protemnodon habitually put more weight on its forelimbs than kangaroos today.”
The old and new views on the modes of locomotion for the Protemnodon. (Image Credit: Billie Jones).
Not All Kangaroos Hop
The new research is a quantitative study of limb proportions, along with qualitative aspects of the anatomy, to confirm the mode of locomotion of the extinct animal. The study provides further evidence in support of the large taxonomic diversity of kangaroos in the Pleistocene of Australia, which were matched by a diversity in their modes of locomotion as well. Extinct kangaroos exhibited a wide range of traits, and the endurance-hopping associated with modern kangaroos is an unusual form of locomotion.
Shambhu Kumar is a science communicator, making complex scientific topics accessible to all. His articles explore breakthroughs in various scientific disciplines, from space exploration to cutting-edge research.
