The myth of the eight-hour sleep

Today, most people seem to have adapted quite well to the eight-hour sleep, but [historian] Ekirch believes many sleeping problems may have roots in the human body’s natural preference for segmented sleep as well as the ubiquity of artificial light.

This could be the root of a condition called sleep maintenance insomnia, where people wake during the night and have trouble getting back to sleep, he suggests.

This is essentially the practice of biphasic sleep, which I’ve been giving a go lately.