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Biology

Unihemispheric Slow-Wave Sleep in Dolphins

Quick fact

Dolphins exhibit unihemispheric slow-wave sleep (USWS), where one brain hemisphere sleeps while the other remains active, allowing them to maintain consciousness, swim, and surface to breathe continuously for up to two weeks.

Why this is interesting

We all know about sleep, but what if you had to keep swimming, avoid predators, and remember to breathe while asleep? Dolphins manage this seemingly impossible task by sleeping with only one half of their brain at a time.