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. The sloth’s 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 six species of sloth, and they come in two varieties: two-toed and three-toed. Three-toed sloths 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 lbs. (about 8 kilograms). The two-toed sloths are slightly bigger than the three-toed sloths, though they share many of the same features.
Thousands of years ago, sloths were much larger, 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. Sloths have an average life span of 20 to 30 years in the wild, but captive sloths tend to live a bit longer. In 2017, a captive sloth at the Adelaide Zoo in Australia died at age 43.
Compared with most mammals, sloths move very slowly. It takes them about a minute to climb only 6 to 8 feet (1.8 to 2.4 meters).
Sloths may be slow climbers, but they are speedy swimmers. They’re naturally buoyant and, like humans, sloths can do the breaststroke with ease. Because sloths inhabit rainforests prone to seasonal flooding, the ability to swim is essential to their survival. Swimming also offers sloths a means of covering more ground in less time when searching for a mate or scoping out new territory, according to Azula, a nonprofit ocean news organization.
Sloths are solitary creatures that rarely interact with one another outside of breeding season. But sloths have little time to feel lonely given their rigorous sleep schedule. Captive sloths typically sleep for 15 to 20 hours per day, while wild sloths rarely rest for more than 10 hours, according to research by the Planck Institute for Ornithology in Starnberg, Germany. Sloths prefer sleeping while curled into a ball in the fork of a tropical tree. They also like to sleep hanging by their claws from tree branches.
Though their ancestors lived in North America, modern sloths live in Central and South America, enjoying the tall trees found in rain, cloud and mangrove forests. Most sloths will occupy several trees during their lifetime, but some, including the three-toed species, may spend their entire lives in the tree they were born in, according to Bradley Trevor Greive’s book, “Priceless: The Vanishing Beauty of A Fragile Planet” (Andrews McMeel Publishing, 2002). For the most part, a sloth’s life revolves around sleeping and eating in its tree homes. These mammals come down from the treetops only to poop (which they do once a week), search for a mate or to establish new territory.