Sloths are identified by the number of long, prominent claws that they have on each front foot. There are both two-toed and three-toed sloths. All sloths are built for life in the treetops.

The Hoffman's two-toed sloth is one of the world's slowest mammals—so sedentary that algae grows on its furry coat. The plant gives it a greenish tint that is useful camouflage in the trees of ...