Ancient sloths lived in trees, on mountains, in deserts, boreal forests and open savannahs. These differences in habitat are primarily what drove the wide difference in size between sloth species.

An Ice Age giant was tumbling around North America during the Late Pleistocene. About the size of a bear, it was actually a kind of enormous sloth that had evolved to thrive in freezing conditions.

Long before today’s tree-dwelling sloths, a 4-ton giant roamed South America — and it may have stood and fought like a bear.

Wilpattu National Park, Sri Lanka’s largest and a prime location for year-round sloth bear sightings, has sparked concern after the sudden deaths of three sloth bears (Melursus ursinus inornatus) ...