Ancient sloths ranged in size from tiny climbers to ground-dwelling giants. Now, researchers report this body size diversity was largely shaped by sloths’ habitats, and that these animals’ precipitous ...

The Smithsonian's National Zoo is home to three Linnaeus's two-toed sloths and shares some sloth basics, but here are three lesser-known sloth facts. 1. The Smithsonian has a collection of fossilized ...

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.