I know this is a joke, but there might be an evolutionary advantage to being able to detect some light and movement when your eyes are closed.
this post was submitted on 13 Nov 2023
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You detect light to know when to wake up or something is happening. Totally blind people also have the mechanism and why they know when it is morning (unless they are missing the organ). I am sure there are other reasons.
Probably so you wake up when it’s light out
I'm now imagining falling asleep around a campfire, and there's... a shadow
My guess, we evolved in hot areas so would often rest during the hottest part of the day. When you're napping your brain can probably notice if a shadow blocks the light alerting you to a potential threat.
That's totally an uneducated guess though.
That's an interesting thought, but I would suggest it's the simple answer: the skin around your eyes is already fairly thin compared to areas that experience frictional forces more often such as the soles of your feet or palms of your hands, so your eyelid would also be a similar thickness to your face skin.
I don't think having thicker eyelids would be much of a disadvantage considering it's not readily visible so predators wouldn't know who's vulnerable like they do when hunting the young or injured, and since humans are social creatures any attack on one would alert the others via sound. Furthermore, how often would a threat cast a shadow over your face before it made itself known in other ways? Probably not enough to give an advantage to one-ply eyelid people to pass on thin genes over thick genes in enough of a way to cause human evolution to run that course.
It's possible, I just don't see it being likely. Like most traits, I think it's just random and has negligible impact on survival/reproduction meaning it doesn't change.
I could be wrong though
Funnily enough I know how this would feel! I gave myself a very bad black eye during a K-hole which burst a vein above my eye causing my eye lid to swell.
It felt like having a very hot and 'sweaty' eye ball covered by a winter duvet. It was so uncomfortably hot I actually got a mini fan to blow air into my eye while I held up the swelling.
Thankfully it resolved itself but thick eye lids are not good.
Your eyeball getting warm. That’s was not the problem I was expecting.
Oh my eyes sweat sometimes too. It's totally not crying. It's sweating. Tough, manly eye sweating.
More of a story than I was expecting, coming to a thread about eyelids!
Thanks for passing on the knowledge
Thank you for this knowledge
How did you give yourself the black eye? 🤔
By being blasted out of his mind on ketamine
Proud, Yoda is
I have thinner eye lids, as I have terrible eczema and as a kid they gave me skin destroyer cream for my eyes... This hit way way way to close to home:X
Thin em out a little more and then you'll have built in diving goggles. Like an alligator!
Fuck eczema
-- Fellow dry-skinned homie
Ass lids? Aren't those normally called pants?
No, that would be an anal bum cover. I’ve spent five years of my life trying to invent an anal bum cover, failing to do so is my greatest regret.
tbf we're missing another pair of eyelids, we used to have a nictatating membrane like many other animals do but nowadays that's only visible as a vestige in the corner next to the nose.
look at reptiles, when they blink there's an extra transparent eyelid that slides in from the middle corner, before the main eyelids.
granted, this wouldn't block any more light as it's transparent, but at least it protects a bit better and lets you get gunk off the eyeball more expediently
fun fact, the eyelids have the thinnest skin of the whole body