Koalas are marsupials belonging to the phascolarctidae family. They are native to Australia and spend most of their time in treetops, feeding on eucalyptus leaves. A diet of mainly eucalyptus leaves does not contain enough nutrition to support vigorous activity, so koalas spend most of the day (around 20 hours) asleep, conserving their energy. They gain necessary fluids from the eucalyptus leaves they eat, so they rarely need to drink water. The name “koala” is believed to mean “does not drink water” in an aboriginal language. Being marsupials, female koalas bring up their young in a pouch in their belly, keeping them safe inside for about six months.