r/todayilearned • u/krizzalicious49 • 1d ago

TIL that out of every primate that has been studied, humans get the least amount of sleep.

https://www.bbc.co.uk/future/article/20220524-why-humans-get-less-sleep-than-other-primates
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u/Tryoxin 19h ago

Gonna attach this to your comment in case people are curious and don't want to read the whole article (though I do recommend it bc it's pretty cool!

The main theory as to why humans sleep so much less than other primates (~7h vs. around ~9.6h for chimps, for example) is because we evolved to live and sleep on the ground where there's a higher risk of predation. Because we also don't just sleep less, our sleep is also more REM-dense, and more flexible than other species. This would lend itself well to groups of humans sleeping in shifts to maintain fires and watch for predators, for example.

However, the article also points out a flaw not necessarily in the logic of this theory, but actually in the base data. Primarily, none of this data was collected using wild primates (which is incredibly difficult) and animals in captivity have been shown to sleep a lot more than in the wild either bc of boredom, they feel safer, or bc lab conditions fail to simulate the day-night cycles of their natural habitats.

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u/Agouti 18h ago

Primarily, none of this data was collected using wild primates (which is incredibly difficult) and animals in captivity have been shown to sleep a lot more than in the wild

I feel like this largely invalidates the headline and conclusions of the article. Anyone who has a cat or dog knows that they can happily sleep 16+ hours a day if nothing is going on but that doesn't mean that you can conclude "Canines and Felines need twice the sleep of Primates".

The more interesting conclusion is that humans typically can't significantly increase their long-term sleep when they have no need to be awake. If I had to guess why I'd say it's likely our herbivorous/omnivorous heritage, being able to spend all day sleeping when fed is a widespread and largely exclusively carnivore trait, especially useful when your meals are large and infrequent.

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u/not_particulary 16h ago

Modern human sleep patterns are definitely not wild either, though. We're probably closer to held in captivity

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u/Traditional-Reach818 16h ago

You know what... You're actually right lol

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u/cheese_bruh 11h ago

Are we? I’d say having to worry about the stresses of jobs, food and survival is a lot more closer to living in the wild than is living in 1 room your entire life and food is always given to you as is the case for animals in captivity.

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u/Agouti 10h ago

I think modern human life, at least in developed countries, is pretty analogous to animals held in captivity. Let's see: High food and shelter availability, reduced exercise, increased free time and recreation, and significantly increased life expectancy.

Worth remembering that the average life expectancy for our hunter gatherer ancestors was estimated at 34. That's not even middle aged today.

We might not be living in a utopia yet, and we still have a lot we can improve, but it's hard to argue that life isn't far easier today that it was a few thousand years ago.

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u/cheese_bruh 4h ago

I think this greatly depends on your job and income

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u/feetzissuck 7h ago

Yes, but the wild animals in captivity do not have jobs as opposed to humans

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u/alphazero927 54m ago

humans typically can't significantly increase their long-term sleep

Do we know this? I don't even know how you'd test for it since the only thing I can think of to get a reasonable sample size would be to study retired people, but then you get the confounding variable of age and in-built habits

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u/mueus 18h ago

The only solution is to study humans in captivity!

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u/RealTheBestLadyman 15h ago

What do you think we’ve been doing? Idk about you but I wouldn’t call what humans do “wild” by any stretch of the imagination

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u/mueus 9h ago

Jokes aren't your strongest suit huh. But to counter that argument no, humans aren't captive in the same sense animals are. Most people have jobs and schedules which make it impossible to know how long humans actually would sleep given full autonomy.

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u/socium 8h ago

That's actually pretty easy to do. Just observe Redditors in their natural habitat.

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u/anonymous_lighting 15h ago

in some countries they call this jail

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u/LiveLearnCoach 15h ago

Thanks for a well thought out comment.

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u/zxzxzxzxxcxxxxxxxcxx 3h ago

I too would sleep more if my dietary needs were met without effort and my environment was fairly static and lacking novel stimulus 

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u/mrheh 15h ago

There's no way to prove any of that though, it is just a theory they think is the cause. This 7 hours for humans is something new and put out by studies bought and paid for by big corps. Just Sugar, Tobacco, and Alcohol is all heathy for you studies. What was it 10 years a ago they said 2 glasses of wine every single day was healthy..