Koalas are a typical animal in Australia that come in northern and southern varieties, with northerns being larger. They have gray fur with a white chest, a flat nose, and feet adapted for climbing trees as the only arboreal marsupial without a tail. Koalas get water from eucalyptus leaves, which is also their sole food source, explaining their Aboriginal name that means "no drink." They are gentle, mostly inactive animals that sleep for 20 hours per day and are only active for about two hours.