Most sloths are about the size of a small dog and they have short, flat flat heads. Their hair is grayish brown but, at times they look grey-green in color because they move so slowly that tiny camouflaging algae grow all over their coats.
Some sloths stay in the same tree for years.
Their huge hooked claws and long arms allow them to spend most of their time hanging upside-down from trees. Since they have a slow metabolism, they need very little food. They feed on fruit, leaves, buds, and young twigs. Sloths also sleep upside-down for up to 18 hours at a time. Mothers also give birth to babies upside-down.