Koala

Koala populations inhabit eucalyptus woodlands along Australia’s eastern seaboard. Specialized sharp claws and rough pads help them climb trunks, while strong arms wrap around branches for hours of rest. Koalas sleep up to 20 hours a day to conserve energy because eucalyptus leaves provide little nutrition and contain toxins. A unique digestive system, including an elongated cecum full of microbes, breaks down fibrous leaves and detoxifies chemicals.

Koalas are marsupials. After a 35-day gestation, a jellybean-sized joey crawls into the mother’s pouch, attaches to a teat, and stays there for about six months. As it grows, the joey rides on its mother’s back, nibbling on “pap”—a special form of the mother’s droppings rich in microbes that prepare the young digestive tract for eucalyptus leaves. Mothers defend their home trees, while males advertise territory with deep bellows at night.

Koalas rely on specific eucalyptus species and need overlapping groups of trees to move safely. They descend to the ground to travel between trees, making them vulnerable to cars and dogs. Drought and heat waves reduce leaf moisture, leading to dehydration, and intensified bushfires can kill thousands of koalas in a single season.

Conservation efforts include protecting corridors of native forest, installing rope canopy bridges and underpasses, and providing watering stations during heat waves. Wildlife hospitals treat koalas injured by vehicles or chlamydia infections, while researchers collect genetic samples to guide captive breeding.

Students learn about koalas by mapping their limited diet, testing absorbency of eucalyptus leaves, or analyzing GPS collar data shared by scientists. Planting koala-friendly trees, keeping dogs leashed near bushland, and reducing carbon emissions all contribute to the survival of these sleepy, button-nosed marsupials.