I ran across an interesting article this morning in New Scientists regarding sleep and sleep habits in the elderly. Turns out their sleep habits of going to bed early and getting up at the crack of dawn may be an adaptation for survival in the wild graciously handed down to us by our ancient human ancestors! Thank you very much H. erectus!!
A study of this phenomena focused on the Hadza people who live in the bushlands of Tanzania. The wild poses many dangers for these people especially while sleeping but NO ONE keeps watch at night! In fact there’s not need to because it seems that natural variation in sleep patterns among the tribesmen means that there is always someone alert enough to sound the alarm if need be.
Fifty years ago psychologist Dr Fredrick Snyder postulated that animals who live in groups stay vigilant during sleep with some sleeping and others acting as sentinels. This is known as the “Sentinel Hypothesis.” What Dr Snyder apparently didn’t realize is that his hypothesis may also apply to HUMANS! Continue Reading