For Insomnia, Look to the Body's Design
Here's a neglected angle in the evolution debate: the health benefits of thinking about your body in terms of its proper design. I wrote here a while back about the barefoot-running trend that observes how, contrary to what your intuition might tell you, we appear to be designed to run without footwear. It minimizes injuries and, when I tried getting into it myself recently, it actually seemed to have a therapeutic effect on an off-again on-again sore knee.
Darwinists have their own explanations for such things, of course. But the lesson seemed to be that it's smart and healthful to try to figure out the correct use of your body and then put that into practice, as you would with any designed device.
Here is another illustration, a BBC story that seeks, convincingly, to debunk the idea that a solid eight-hour sleep cycle is best for us. A very close family member of mine with insomnia difficulties has trouble getting what she thinks of as a full night's sleep. Why? Because about half way through the night she wakes and then tosses and turns after that.
The explanation seems to be that until modern times, across many cultures, it was normal to sleep in two blocks of time: from somewhat after dusk till midnight or so, then up out of bed and active for an hour or two, then back to sleep for the balance of your rest needs. You would thus sleep for about eight hours but not, as current culture tell us we must, a solid eight. The insistence on a solid block is a cultural and technological artifact.
Nowadays, when we wake from that initial four-hour block we're liable to experience anxiety that builds on itself -- after all, we assume we should be asleep, not awake! This interferes with our ability to relax and sleep through the second four-hour chunk of rest. The whole subject has deep historical roots, as the BBC explains:
In 2001, historian Roger Ekirch of Virginia Tech published a seminal paper, drawn from 16 years of research, revealing a wealth of historical evidence that humans used to sleep in two distinct chunks.This "second sleep" idea sounds like the way we're designed though no doubt you could come up with an evolutionary just-so story to account for it in adaptive terms. (Off the top of my head, in good Darwinian fashion, I can't think of one just now.) It would be no less convincing to suggest that there's a spiritual reason for it. Jewish and Christian traditions alike include practices going back centuries or millennia centered on prayer and meditation timed to occur at midnight.
His book At Day's Close: Night in Times Past, published four years later, unearths more than 500 references to a segmented sleeping pattern -- in diaries, court records, medical books and literature, from Homer's Odyssey to an anthropological account of modern tribes in Nigeria.
...[T]hese references describe a first sleep which began about two hours after dusk, followed by waking period of one or two hours and then a second sleep.
"It's not just the number of references -- it is the way they refer to it, as if it was common knowledge," Ekirch says.
The Jewish version is called Tikkun Chatzot, the Midnight Rectification. King David himself rose at this time to pray, as the Psalm suggests (119:62): "At midnight I will rise to give thanks unto thee."
Photo credit: M. Angel Herrero, Flickr.