koala

The koala is a small bear-like, tree-dwelling, herbivorous marsupial, which averages about 9kg in weight. Its fur is thick and usually ash grey with a bit of brown in places.
The koala is the only mammal, other than the Greater Glider and Ringtail Possum, which can survive on a diet of leaves The koala gets its name from a ancient Aboriginal word meaning "no drink" because it receives over 90% of its hydration from the Eucalyptus leaves (also known as gum leaves) it eats, and only drinks when ill or times when there is not enough moisture in the leaves.