Diprotodon was the largest known marsupial, belonging to the family Diprotodontidae. Fossils show this group persisted into the later part of the Ice Age, surviving through much of the Pleistocene epoch, while earlier relatives are recorded from the late Oligocene and the early Miocene.
Description
The animal had a heavy, barrel-shaped body and a broad skull; in overall build it resembled a hornless rhinoceros. Its forefeet were rotated inwards in a way similar to a wombat, producing a pigeon‑toed gait. The front feet bore sturdy claws, which may have been used to dig for roots and tubers. Impressions of hairy footpads indicate the skin was covered with fur rather than being bare like a true rhino.
Fossil evidence
Remains have been recovered from many locations across Australia, though no definite records come from Tasmania. Some female skeletons preserved juvenile remains where a marsupial pouch would be expected, supporting the interpretation that young were carried in a pouch.
Size and build
Large individuals approached the proportions of a modern hippopotamus in bulk: about three metres from snout to tail, roughly two metres tall at the shoulder, and weighing on the order of a few thousand kilograms. These dimensions make it the heaviest marsupial known from the fossil record.
Ecology and extinction
Many researchers infer a semi‑aquatic or water-associated mode of life, with some comparisons drawn to the behaviour of a hippo. The disappearance of Diprotodon around 40,000 years ago is generally attributed to a combination of climatic changes—including prolonged dry spells—and additional pressures following the arrival and spread of Aboriginal peoples across the continent.