A single species, Phascolarctos cinereus, which is a member of the family Phalangeridae in the mammalian order Marsupialia (pouch-bearing animals). It is a small, clean, affectionate animal that weighs from 11 to 17 lb (5 to 8 kg) when mature. Koalas are restricted to eastern Australia, where the eucalyptus grows. Not only do they have a specialized diet of eucalyptus leaves, but the leaves must be of a certain age from a specific species of tree, and the tree must grow upon a certain type of soil. Each adult will eat an average of 2–3 lb (0.9–1.5 kg) of leaves each day. While the diet is a definite limiting factor to an increase in the population, millions died from epidemic diseases at the turn of the twentieth century, and later thousands were killed for their fur. These animals are now strictly protected by the Australian government because their numbers are small. Exportation is prohibited.