Although many people think a koala is a bear, it is not. The koala is a type of mammal called a marsupial. A kangaroo is also a marsupial. These mammal carry their babies in a pouch. The kangaroo's pouch is on her stomach, but the koala's pouch is on her back. Both feed their babies milk and keep them secure in their pouch until they are strong enough to survive on their own.