I wonder about the life-styles of the inhabitants of ancient civilizations. As a particular case, if we consider the era of Sumer, what are the significant diversities compared to rural life today?
According to historian A. Roger Ekirch's At Day's Close, peoples in pre-industrial societies actually went to bed as soon at it was too dark to work, and slept (and still do sleep in such areas today) in two fourish-hour phases, interrupted by a short period of activity. He found numerous references to this in literature, from Medieval literature to Homer. However, the electric lighting available to modern industrialized societies resulted in people staying active after dark, and thus needing to skip the middle activity period to make up for it.
Ekirch argues that these days we have become so used to an uninterrupted 6-8 hour sleep that we have trouble translating the concepts of "first sleep" and "second sleep" from older literature (hiding the fact that they existed), and those who wake up for a while in the middle of the night often think they have some kind of disorder.