Do you know the phase of the moon, without looking it up? Of course you don't. You have no need to. But all of your pre-history ancestors did, young and old, male and female. And they all knew it very well. Did they worship or were they in awl of the moon? Nope, not at all. They HAD to know. I have been described with various adjectives, by many people, at various times, as being pre-historic, so I must be an expert. All pre-history cultures had two wake periods and two sleep periods a day. The first half of the day was for survival related work. All people would knock off around noon and have a second sleep period thru midday. Upon wakening in early evening, one could finish survival needs (seasonal hunting, checking flock for night), but mainly the second part of the day was for social interaction. Families and group gatherings, dancing. BUT mostly for individual sex. Sex was about all they had and they used it. If you wanted to get any, you will learn to move and plan in moonlight. If you make a date for Friday nite, you better know if you can see well enough for the rendezvous. By the time you are 12 or 13, (most likely younger) you will know the coming phases and light available. The flicker of a flame would limit your night vision. And there was no street lighting. Many, many other activities were done in the cool of moonlight. Hunting, fishing and gathering. Even though our nite vision is poor, we have adapted and have always been both night and day creatures. One of the first patterns we learned was the timing of night lightness. Which is forgotten now. And I highly recommend a two sleep period day. Keeps one in balance. And you might get a little.