A lot of biological processes are kicked off by light exposure, and by "number of hours of light exposure". For example, the change in an animal's coat type (s

A lot of biological processes are kicked off by light exposure, and by "number of hours of light exposure". For example, the change in an animal's coat type (summer vs winter) is triggered by the number of hours of sun they are exposed to. Once the days get shorter, the summer coat falls out and the winter coat starts growing in. Presumably that means someplace your body has the equivalent of an accumulator running measuring hours of sun exposure. :-D (This is also why people deprived of light, or exposed to non-stop light, quickly find a lot of their body's rhymes get way out of wack.) Anyway AFAIK that system is part of how we adjust, eventually, to changes in time zone. A lot of other things in our bodies are cyclical throughout the day, month, and seasons. Including men's hormone levels, with testosterone "peaking in October and ebbing in April" [https://www.apa.org/monitor/2011/03/hormones#:~:text=Men%27s%20testosterone%20cycles%20fluctuate%20from,books%20on%20men%20and%20hormones https://www.apa.org/monitor/2011/03/hormones#:~:text=Men%27s....] I guess my TL;DR is that we're still animals and we can't logic / alarm clock our way out of biology.