"Sleep We Have Lost"
history.vt.edu
history.vt.edu
In my opinion this is vastly more "useful" than the alternative: This is a nice overview and invites you to dive deeper into any of these sources.
Edit: Though after skimming over the rest of them, most of them seem to be referencing pretty much the same thing. I can kind of see what you found odd.
Edit 2: Definitely looks like this is just a list of commentary specifically about the work of Roger Ekirch, who is is also the owner of that site - definitely might be biased (as in not an exhaustive list) then.
I think the site is intended as marketing for the article, like the quotes from reviews that appear on the backs of books. Of course the article itself is not linked very prominently, so this is kind of hard to figure out.
I've read this a few times. I think it may not necessarily be a bad thing that we get all of our sleep in one continuous block. It may have been as vestigial behavior from our ancestors -- fearing predators and other threats.
The advent of artificial light has brought lots of benefits but it clearly has some big drawbacks wrt sleep.
Cheap lighting has simply allowed people away from the equator to sleep in the more natural pattern, if you grant that humans are less adapted to cold climes than to tropical ones.
[1] https://www.theatlantic.com/science/archive/2015/10/the-many...