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.

Imagine a sloth. You probably picture a medium-sized, tree-dwelling creature hanging from a branch. Today's sloths—commonly ...

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. But ...

Bones from an extinct ground sloth that stood between 8 and 10 feet tall were found in Kansas. Photo from the Illinois State Museum. At the end of the Pleistocene Epoch, 2.6 million to 11,700 years ...