Dolphins engage in a fascinating biological process called unihemispheric slow-wave sleep, which allows them to shut down only one half of their brain at a time while resting.

A closer look

Dolphins engage in a fascinating biological process called unihemispheric slow-wave sleep, which allows them to shut down only one half of their brain at a time while resting. During this partial slumber, the dolphin keeps one eye completely open to monitor its surroundings for predators and remember to occasionally swim to the surface for a breath of fresh air. They literally sleepwalk through the ocean, constantly alternating which side of their brain gets to take a nap while the other stays on the clock doing the tedious work of keeping them alive. It is the ultimate survival mechanism for an aquatic mammal, and frankly, a skill that most sleep-deprived corporate employees would absolutely kill to possess during a particularly boring three-hour marketing meeting