Wombats Koala Possums Wallabies and Kangaroos: Diprotodontia

Diprotodonts are mainly active at twilight and night. The only species that is active exclusively during the day is the musky rat-kangaroo, although some diprotodonts that live in the forest tend to be active during both day and night. The mountain pygmy possum is the only diprotodont, and in fact the only marsupial, to hibernate or become inactive in cold months.

Many diprotodonts live alone, coming together only to mate, but there are exceptions. Kangaroos tend to associate in loose groups, called mobs, but there is no definite leader and no cooperation among members as there is in a structured group like a wolf pack. Common wombats visit each other's burrows and are not aggressive toward each other, but they do not live together in social groups. Likewise, koalas live near each other, but have their own personal space. On the other hand, hairy-nosed wombats may live in large groups of up to fifty animals, sharing a series of interconnected burrows. Small possums, such as the honey possum and feather-tailed possum, may huddle together for warmth, but larger species of possum live alone. Diprotodonts can be very noisy. They use barking, sneezing, hissing, grunting, gurgling, and growling to mark their territories and communicate their moods to other members of their own species.

In terms of reproduction, diprotodonts, like all marsupials, have short (two weeks to one month) pregnancies. At birth, the newborn is tiny (in some species, as small as a jelly bean). The young are carried in the mother's pouch for weeks or months until they can survive in the outside world. Many species continue to nurse their young after they leave the pouch. Wombats and possums carry their young on their back after they outgrow the pouch. In many species the young may remain with the mother outside the pouch for up to several months before becoming completely independent.