Diprotodon optatum is the largest marsupial known to have existed.

Diprotodon optatum is the largest marsupial known to have existed. Laurie Beirne

Zoology

First evidence of marsupial migration

Tooth enamel tells the tale of a massive travelling wombat.

A huge wombat-like creature trekked across Australia with the seasons some 300,000 years ago. It represents the only known example of a regularly migrating marsupial.

Gilbert Price at the University of Queensland in Brisbane, Australia, and his colleagues studied enamel from the incisor of a Diprotodon optatum, which could reach almost 3,000 kilograms and is the largest marsupial known to have existed. The enamel layers contain chemical signatures of the animal’s plant-based diet in the last three years of its life and provide clues to where it grazed. The team concludes that this individual roamed repeatedly north and south in an area of eastern Australia, covering up to 200 kilometres per year, much like the annual oscillations of many mammals in East Africa today. Modern marsupials are thought to be too small for such long-distance voyages.