Really? My instinctive reaction to this statement is that it's quackery. Would be very interested to see headlines appear about this if it's true.

> humans are weird outliers—we’re the shortest sleeping primates, yet we pack in the most REM sleep relative to this short duration

Isn't that sort of the point? Sleep is a detrimental necessity and the more efficient an organism is in needing less of it, the more effective it can be because it simply has more time to get ahead of the others?

It's still very odd that no species has ended up evolving a continuous maintenance system that can run while conscious, the benefits when hunting other animals that need sleep would be enormous, so there has to be significant evolutionary push for it. I suppose the single hemisphere sleep some marine mammals do is part of the way there, but it is at most a lazy workaround. Practically all other organs have evolved to run 24/7 for up to a century without a single break, what makes brains so universally different?

And why wouldn't they? This is (presumably) the only kind of sleep they know.

Like, it seems obvious to me that sleep has a higher opportunity cost in humans than most other animals. So naturally there's more evolutionary pressure in humans to sleep more efficiently.

Is this actually true? Dunno! But it was really weird that it doesn't get brought up.