Massive Marsupial Found

Artist illustration of northern Australia in Pleistocene times, with diprotodon in foreground. Artwork: Dorothy Dunphy

Scientists have uncovered a near-complete skeleton of a prehistoric giant marsupial in far north Queensland.  About the size of a rhinoceros, Diprotodon optatum was the largest marsupial that ever lived. It weighed as much as three tons, stood nearly two meters tall at the shoulder and was about 3.5 meters long.

Diprotodon, which is distantly related to wombats, was the last surviving species of its family.  It was the first prehistoric beast discovered in Australia and is one of the most recognized members of the Australian megafauna. Diprotodon lived in mobs right across the Australian mainland until it became extinct sometime during the past 50,000 years.

Palaeontologists from the University of New South Wales (UNSW), the Queensland Museum and the University of Queensland made the discovery along the Leichhardt River between Burketown and Normanton, in the Gulf of Carpentaria. It is one of the best preserved and most complete skeletons of Diprotodon ever found and is the most northerly specimen known.

An arm bone (humerus) of the giant marsupial was first discovered at the site, on Floraville Station, late in the field season of 2010.

The scientists recently returned to excavate the skull, jaws and rest of the skeleton with the enthusiastic help of local school children and community members, with the support of the Xstrata Community Partnership Program North Queensland.

Supervising the dig are UNSW’s Professor Mike Archer and Henk Godthelp, Dr. Scott Hocknull from the Queensland Museum and Dr. Gilbert Price from the University of Queensland.

What caused the extinction of Diprotodon and other members of the Australian megafauna is hotly debated.  Overkill by humans and climate change have both been blamed.

With bone and other samples now submitted for determining the age of the Leichhardt River Diprotodon, the scientists expect that this significant specimen will provide much-needed new data to help resolve this controversy.

Other megafauna found by the palaeontologists on Floraville Station during the excavation include giant short-faced kangaroos, crocodiles and a giant goanna.

The fossil research is part of an ARC Linkage Project investigating environmental change in northern Australia. Led by Associate Professor Sue Hand, the research also includes scientists from ANSTO, the Universities of Melbourne and Wollongong, and Outback at Isa. It is supported by Mount Isa City Council.