@flo “All kinds of studies have been found to be garbage, later on.”
Appeal to ignorance fallacy. Just because something might turn out to be false does not mean that we should reject it when all available evidence supports it. There are multiple studies from multiple sources corroborating @JLeslie‘s point. So while our acceptance of any scientific consensus should always be provisional (due to the fallibilistic nature of science), the rational and intelligent person does not reject evidence solely on the basis that it could be mistaken.
“It’s hi-lie-ree-yes, ‘it doesn’t matter who you agree with,’ you did the same thing. You agreed with Webmd.”
No. What @JLeslie did was provide evidence that happened to be in the form of an article on the WebMD. She’s not just agreeing with someone’s opinion, she’s backing up her point with scientific evidence. If you cannot understand the difference, then it’s no surprise that you regularly spew ignorance all over this website.
Furthermore, it’s worth noting that what @JLeslie and @josie have said does not actually contradict what @bbaljm1990, @ibstubro, and @SQUEEKY2 have said. Your confusion on this score seems to come down to a misunderstanding of what it means to say that something comes from nature. You gloss this here as meaning “impossible to change,” but you also seem to have a very broad interpretation of what “change” means. One can adapt to something without changing it (e.g., people who adapt to losing a limb). Therefore, your claim that “if most people can adapt to any period of the day to sleep, then it can’t be nature” is simply a non sequitur (for those keeping score at home, that’s another fallacy).
Now let’s look back at the actual claims that were made. Here’s what @josie said: “pursuing existence in the dark is contrary to our nature, and thus subject to risk” (emphasis added). “Subject to risk” is not the same thing as “impossible.” It just means that the adjustment will cost you—and that’s what @JLeslie‘s studies point out: there are risks and costs to a nocturnal lifestyle. It’s possible to pull it off, and some people will have an easier time of it than others. But there are no guarantees. Pretty straightforward, really.