According to National Geographic, koalas eat eucalyptus leaves, not bamboo. Koalas are marsupials that live in eastern Australia. Their habitats include areas where the eucalyptus tree grows.
Koalas rarely leave the eucalyptus trees they feed from and sleep up to 18 hours a day. Their claws and opposable digits allow easy climbing. Most of the moisture the koala intakes is derived from eucalyptus leaves, allowing the koala to stay aloft in its tree for longer durations. Eucalyptus leaves are poisonous, but the koala has a specialized digestive tract that can counter the effects of the poison. Because koalas spend most of their waking time eating, they smell similar to the oil of the eucalyptus leaves.