The Koala is a small, bear-like herbivorous marsupial with thick ash-gray fur. They spend the majority of their time in trees, with the adult males ranging in weight from 8 to 14 kg. and the females from 6 to 11 kg. The heavier Koalas typically come from Southern Australia because of the cooler climate which requires a thicker fur and more fat for insulation.
The word "Koala" comes from an old Aboriginal word meaning "no drink" because they obtain 90% of their fluid intake from the eucalyptus leaves they eat. Koala's only drink when they are ill or when there isn't enough moisture in the leaves, such as during a drought. The eucalyptus leaves are very high in fiber and low in nutrition. Because of this, Koalas have a high metabolic rate in order to obtain the maximum amount of energy from the 200 to 500 grams of leaves they eat each day. To cope with the low nutritional value of the leaves, Koalas will sometime eat small amounts of soil to provide the minerals they need in their diet. Aside from the Greater Glider and the Ringtail Possum, the Koala is the only animal that can have a diet of entirely eucalyptus leaves. However, the Koalas will sometimes like a change of pace and have been known to eat several different types of leaves, including wattle and tea trees.
Today, most Koalas are found in New South Wales, Victoria, Queensland, and South Australia. Much like humans, Koalas live in societies and are frequently in contact with other koalas. However, koalas are highly territorial, and need to maintain their "home range," which is comprised of several "home range trees" and "food trees." Many time home ranges for koalas overlap and it is in those overlapping areas that much of the koalas interaction with other koalas occurs. Some of the trees in the home range are simply for eating, while others can just be used to sleep in.