Imagine a sloth. You probably picture a medium-sized, tree-dwelling creature hanging from a branch. Today's sloths—commonly featured on children's backpacks, stationery and lunch boxes—are slow-moving ...

Credit: flickr You wouldn’t expect it from an animal that barely moves, but sloths are excellent swimmers. They use a sort of doggy paddle and can hold their breath for up to 40 minutes. Water ...

Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news on fascinating discoveries, scientific advancements and more. Modern sloths hang ...