The rich color of a red kangaroo (Macropus rufus) male, right, compared to the smaller and more drab female at water. The males are called "boomers" and the females "blue flyers." (Photo by Wayne Lawler/Photo Researchers, Inc. Reproduced by permission.)

roos), the hind legs are larger and more powerful than those at the front, and the hind feet are very long (the group and generic names macropod and Macropus mean "big footed"). In most macropods the first hind toe is absent.

Diprotodonts have soft fur—that of many possums and the koala is very woolly. The majority of species are some shade of gray or brown, but a few are rather dramatically colored— for example Goodfellow's tree kangaroo (Dendrolagus goodfel-lowi), with a rich cinnamon red and gold coat and the yellow-footed rock wallaby (Petrogale xanthopus), whose yellow legs, feet, and ears, red and yellow-banded tail, and bold white cheek flashes contrast with gray body fur and make it one of the world's more decorative mammals.

Gliding possums are equipped with a built-in parachute, formed from a web of skin extending along each flank from the front to back legs. The precise structure of this membrane (called the patagium) varies between the three families of glider. In the pseudocheirid greater glider it stretches from elbow of the forelimb to ankle of the hind, while in the ac-robatid pygmy glider it links wrist to knee. The lesser gliders (family Petauridae) have the most complete patagium, extending from wrist to ankle. None of the marsupial gliders have a tail membrane, although the tail of the pygmy glider is modified to assist the gliding process, with a vane of hairs along each side earning the species its alternative common name feathertail glider.

Convergent evolution is a recurring theme in marsupial history, and the diprotodonts are no exception. The diverse diprotodont body forms and lifestyles show striking similarities with mammals of several other orders. For example, the head of kangaroos is deer-like, with a long muzzle, erect, mobile ears and large bulging eyes situated on the side of the head. Like deer, kangaroos have good all-round hearing and vision and long, powerful legs capable of making dramatic leaps and propelling the animal at speed—all essential for avoiding predators in open habitats. The stout, badgerlike form of the wombats is an adaptation to burrowing, with strong legs, claws and jaws all contributing to the effort of excavating what can be very hard soils. With their woolly fur, round face, large, forward-facing eyes and careful climbing technique, the cuscuses are strongly reminiscent of primates such as lorises and pottos. The pygmy possums are the marsupial equivalent of European dormouse in looks and some aspects of behavior—they climb with the aid of a prehensile tail and enter deep hibernation in cold weather. The sugar glider (Petaurus breviceps) and Leadbeater's possum resemble species of flying and non-flying squirrel respectively.

A red-necked wallaby (Macropus rufogriseus banksianus), showing the bright rufous mantle characteristic of this most common and widespread of the medium-sized macropodids of eastern Australia. (Photo by Wayne Lawler/Photo Researchers, Inc. Reproduced by permission.)
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