Sloths are tropical mammals that live in Central and South America. They use their long claws to hang onto branches while they feast on the leaves that other animals can't reach. Unfortunately for the sloth, their long claws — 3 to 4 inches (8 to 10 centimeters) — make walking on the ground difficult, so they spend most of their time in the tall trees they call home.
There are two categories of sloths. The two-toed sloth is slightly bigger than the three-toed sloth, though they share many of the same features. They are about the size of a medium-sized dog at around 23 to 27 inches (58 to 68 cm) and 17.5 to 18.75 pounds (about 8 kilograms).
Thousands of years ago, sloths were much bigger, according to the San Diego Zoo. Ancient sloths could grow to be as large as an elephant. They roamed North America and became extinct around 10,000 years ago.