I'm not sure I agree with the original characterization of why waking up in the morning became seen as virtuous. As I understand it, people up until the Industrial Revolution had pretty flexible sleep schedules. They'd wake up early enough to do work (early in the summer), but if there wasn't work to do (winter), they'd sleep in. Graham Robb, in The Discovery of France, talks about how farmers in the French countryside would even enter a near-hibernation state in the winter, where they'd get up once every other day, to take care of basic bodily functions and then go back to bed.
Waking up early became virtuous in the Industrial Revolution, when factory owners deliberately inculcated that virtue into their workers, with institutions like the factory clock. Then their children were inculcated with that virtue in schools, which started at roughly the same time that the factories did. It wasn't about signalling, it wasn't about work benefiting from sunlight, it was about coordinating a mass of workers to all come in at the same time, and having them work for as long as possible before sunlight ran out. It wasn't a gradual progression. It was a fairly sudden change that took place over a couple of decades.
As a meta point, I think rationalists tend to underestimate the effects of the Industrial Revolution, how effective it was at completely wiping out the social structures and daily habits of people that lived before that era, and the level of violence required to do so.
I'm very interested in that meta point you brought up. Do you know of any books or articles that attempt to comprehensively describe the "before and after" picture of people's daily lives?
One good book is the one I mentioned in my post, The Discovery of France, by Graham Robb, though, like one might imagine, it's focused on France. Another good book is Debt: The First 5000 Years, by David Graeber. It's a bit of an anti-capitalist polemic, but it does go into great detail about how people lived before "modern" industrialization and finance came into their lives and the violence that had to be inflicted on these (mainly colonial) populations in order to get them to accept these institutions. The perennially cited Seeing Like A State is also a good resource, setting up the pattern by which (sometimes) well-meaning reformers screw up traditional societies by attempting to modernize them in a root-and-branch fashion. Finally, Thompson's The Making of the English Working Class (available online) covers the workers' transition from agrarian and handicrafts work to a self-conscious social class.
I think that the general idea of Signal Seeding is both useful and true, but I agree that sleeping late is not a great example (although for different reasons than quanticle).
I used to have the belief of "who cares when I sleep, as long as I get the same amount of work done?" But now I think sleeping late is actually inherently harmful, and pointing to an unhealthy state of being that isn't just from signalling or other social reasons.
Times when I have been depressed it is really hard to both go to bed and get out of bed. Times when I am well functioning, it's hard to sleep late. If I am camping or spending large amounts of time outdoors it's also hard to sleep late (so I don't think this is a product of the Industrial Revolution).
While depression does alter circadian rhythms, it is also true that there is significant variation in "normal" sleep profiles among humans. Some people naturally rise early, whereas others have a built-in predilection for staying up late and waking up late.
But this isn't what KatjaGrace was getting at, necessarily. I think they were going after the moral value of getting up early vs. getting up late, and trying to answer why getting up early became the virtuous choice.
What does it say about a person if they never get up before noon?
If they are the first person to exist, it probably says that morning was for some reason a convenient time to sleep.
If they live in modern society, it might say that they are lazy and weak willed.
How did getting up at one time or another come to signal laziness? You still have to get up once per day.
One story I can imagine is that originally there was some weaker reason to get up early. For instance if your work benefited by sunlight, you could get a bit more in. And then since that was a reasonable thing to do, people who didn’t do it looked like they were less good at getting up. Which made getting up early even better thing to do, so that everyone knows that you can.
And then people who had been on the fence before about whether to bother getting up early started to find it worth their while. Making the remaining noon-sleepers even more weak willed on average. And so it continues, until sleeping until the afternoon strongly suggests laziness.
In general, if an action is a tiny bit good, not doing it can look a tiny bit bad (or stupid, or lazy, or incapable). Which makes it better to do, which makes it look worse to not do it, and so on. And maybe in the end the speck of good that started this disappears, but the value of sending the signal if you can is enough that the equilibrium is stable.
Does this actually happen?