No, not that one. I think I've done my reproductive duty to the species and then some, both quantitatively and qualitatively.
More kind of related to, but not exactly the same as, circadian rhythm.
I normally consider myself a fairly clock-bound person. I was brought up on the maxim "if you're not 15 minutes early, you're late," and I normally try to keep a fairly tight grip on time. I have a bedtime that I don't always stick strictly to, and a getting-up time that I do stick strictly to, even if I don't mean to (if I don't set my alarm, I usually wake up within a few minutes either way of when I would have had my alarm set for). And so on and so forth.
But when I'm alone (except for the pets) for days at a time, as now (Tamara and the kids are up north for a funeral and related activities), I realize how much of my day seems to rely on routine, expected cues. When is Tamara leaving for work? When is she returning? What time should there be a consultation on what's for dinner tonight, and when will that dinner be eaten? Etc., etc.
With all of those cues missing, I'm often shocked when I look at a clock. It may be hours earlier or later than I "feel" like it is. That's kind of screwing with my sleep and other schedule items.
It has not, however, kept me from meeting my goal of averaging one post per day or more. This is the 365th post of 2021.