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) ...

The Smithsonian’s National Zoo and Conservation Biology Institute (NZCBI) announced Jan. 6 that two sloth bear cubs were born in their care Dec. 7 and will debut in an exhibit this spring. The ...

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.