Sleep

3 segments

Birds do it, bees do it...yet science still can't answer the basic question: why do we sleep?

Every creature on the planet sleeps--from giant humpback whales to teeny fruit flies. What does it do for us, and what happens when we go without? We take a peek at iguanas sleeping with one eye open, get in bed with a pair of sleep-deprived new parents, and eavesdrop on the uneasy dreams of rats.