We spend one third of our lives unconscious.

Sleeping. And we don’t know why we sleep. Of course, there are explanations that are proffered. Sleep removes toxins. Or sleep gives time for synapses in the brain to rejuvenate. Or sleep regulates mood and libido.

All of which are true, and none of which explain what goes on every night. It’s a true mystery, and despite knowing about REM sleep and brain recharging and a lot of other stuff that happen during sleep, we can’t explain why we become unconscious for hours every day.

Vulnerable.

Unprotected.

Unable to care for the young, or anyone else who needs our care.

Evolutionary theory posits that there’s an adaptation over extremely long amounts of time. And those individuals who have better adaptations will be able to live longer, survive better, and generally be around longer to reproduce more, and, they hope, have those same positive adaptations.

None of which makes sense when we think about sleep.

Because sleep is dangerous. Everyone knows this if you’ve ever been awakened by an emergency that required your reasoned response. Most people need time to become alert enough to do what they need to do.

By evolutionary theory, sleep should have been adapted out millions of years ago. But it hasn’t. We are still unconscious every night. For 7 or 8 hours. And we’re paralyzed. Unable to protect ourselves or others.