Add Yahoo as a preferred source to see more of our stories on Google. © Smithsonian’s National Zoo and Conservation Biology Institute The post A Win for the ...

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

Defecating exposes sloths to predators on the jungle floor. An unexpected ally benefits, and returns the favor. A brown-throated three-toed sloth peers over a tree's buttress root while defecating on ...