Sea otters are the smallest marine mammals, but they have some incredible adaptations to thrive in the ocean. Unlike seals and whales, they don’t have a thick layer of blubber to keep them warm.

Otters are one of the smartest species on the planet. Sometimes they forget they're not humans. We're starting to realize how smart otters really are. They know how to play basketball. They know ...

River otters really do have more fun. They jostle, belly-slide across ice and snow and toboggan down embankments into water. Splish splash. Few mammals are known to frolic as much as otters do ...