So I've seen a number of articles about Segmented Sleep and the idea that we used to sleep in two phases based on historical evidence, etc. However, this set of circumstances applies rather uniquely to Western Europe. None of the articles I've looked at have explained, then, why the continuous sleep pattern we see now seems to hold true for the Middle East and Asia as well.
Some recent research suggests that normal human sleep has always been in one continuous block in places near the equator. Then segmented sleep developed after humans migrated to places like Europe where sunrise/sunset times vary more. According to this hypothesis, segmented sleep was only a temporary phenomenon, before electric light caused a return to continuous sleep.
Thank you for this. There's always this huge elephant in the room never addressed in these articles on sleep - particularly prior to the use of internal electrical lighting; the time of year. Your amount of sleep and how you sleep would change substantially based on whether there was 4 hours or 14 hours of darkness. Yet it never comes up in these catch all types of articles.
The fantastically great podcast, backstory, did a piece on it as well. There was supposedly a stage of the us temperance movement against second sleep.
