Although bear-like in appearance, koalas are not bears but tree-dwelling marsupials related to the kangaroo and wombat. Marsupials are mammals that carry their young in a pouch. Females give birth to one koala joey at a time. After a short gestation period of 34-36 days, the joey moves into the pouch where it remains for several months. A young joey will continue to stay with the mother after it exits the pouch, clinging to her back for nearly a year or until another joey is born and moves to the pouch.
Adult koalas reach up to 30 pounds and are covered in thick wooly fur that protects from heat, cold and rain. The coat is ash-gray to brown in color with patches of white on the chest and neck, inside the arms and legs, and inside the ears. Distinguishing characteristics of koalas include their large, flat, black noses and pear-shaped bodies. Males also have a brown “scent gland” in the center of the chest, which they rub at the base of trees to attract groups of females. Males are very territorial with their harem during mating season.
These mostly nocturnal animals spend 18-20 hours a day resting and sleeping. Their diet is quite specialized, consisting exclusively of the leaves of the eucalyptus tree. They primarily get their moisture from eating these leaves rather than from drinking.