Why do we sleep? A bedtime story

We’re all sleepless. Like air, food, and water, sleep is integral to our health—and to our survival. And yet, we certainly don’t treat it that way. In fact, as a society, we’ve long been struggling with insomnia, sleep deprivation, and other forms of sleeplessness. So, why do we sleep? Journalist Sky Dylan-Robbins takes a generational look at the subject, thanks to a feature her mother, Ellie Dylan, reported exactly 40 years ago. This is a bedtime story for America—a journey through time that brings us back to the first sleep studies on REM sleep, uncovering how things got so bad, and what we can do to change our habits—and our lives. Real counting sheep included.