Humans do very little when we sleep. This might not seem like a big deal, until you look to the dolphins as they sleep and swim with the pod. Or fur seals, who can sleep while watching out for sharks.

Ever wonder how animals sleep in the wild? It's not always as you may think. From sloths who hang upside down from trees to dolphins sleeping with one eye open, the animal kingdom is full of quirky ...

Discover animals who don’t sleep in a conventional way! Learn about marine mammals like dolphins and orcas that use ...