Sloths move slowly, and they spend most of their lives hanging upside down from tree branches, where their long, curved claws hook onto the branches. Sloths are slow because their leaf diet gives them little energy and their bodies use energy very slowly. There are two kinds of sloth, two-toed sloths and three-toed sloths, which are named for the claws on their front feet. In all, there are six species of sloth: two kinds of two-toed sloth and four kinds of three-toed sloth.

Sloths mostly eat leaves. Leaves give sloths very little energy, so sloths get few calories from their food. Sloths eat leaves from more than 90 kinds of trees, but one sloth usually sticks to about six to twelve kinds. A sloth's stomach has four chambers full of bacteria that help break down the tough leaves. A single leaf can take about a month to travel through a sloth's body. Sloths get water from the leaves they eat, and also by lapping dew off leaves and fruit.

Sloth fur is long and thick, so sloths look bigger than they are. Sloth hairs have grooves or cracks where algae can take hold and grow. Green algae in the fur help the sloth blend in with the green leaves. A sloth's fur is also home to moths, beetles and other tiny animals. A sloth's body temperature rises and falls with the temperature around it. Sloths warm up by moving into the sun and cool off by moving into the shade.

You may have heard that sloths sleep almost all day. In a study of wild three-toed sloths in Panama, the sloths slept about 9.6 hours a day, much less than sloths in captivity, and two-toed sloths are active at night. Sloths are hunted by big birds and big cats, such as harpy eagles, jaguars and ocelots, and moving slowly helps sloths go unnoticed by hunters that find prey by sight. A curled-up sloth can look like a termite nest or a knot in the wood.

About once a week, a sloth climbs down from its tree to go to the bathroom. Sloths live alone, except for a mother with her baby or sloths that are mating. A mother sloth has one baby at a time, and the baby crawls onto its mother's belly right after it is born and clings to her. Sloths are mammals, so a mother sloth feeds her baby milk. A baby sloth learns which leaves are safe to eat by tasting leaves from its mother's mouth.

Sloths live in trees, high up in the rainforest canopy, in the tropical forests of Central and South America. The pygmy three-toed sloth lives only on one small island off the coast of Panama. On the ground, sloths cannot really walk. They drag themselves along with their claws and front legs. Sloths cannot jump from branch to branch the way monkeys do, so they need trees whose branches touch. As of November 2026, sloths depend on forests, and many forests where they live are being cut down for farms, ranches, towns and logging.

Words to know

• captivity: not wild
• logging: cutting trees
• dew: water drops
• algae: green growth