Like, 1 in 200 people is colourblind, or something?
....
Again, you're talking genetics, where it is clearly broken down in 2,3,4.
However like pretty much everything else, it's not that clear cut just because the plans were.
Two people with the same amount of different types of cones are not guaranteed to have the same rod/cone ratio. Even when they have similar genetics for the ratio, things rarely go according to plan as a human develops.
Like, you know that's why facial symmetry is attractive right? It shows that things on both halves went according to plan. Which especially for women is a huge bonus for reproductive health.
Especially for something made up of a whole bunch of small things like rods/cones, it's not even perfect for identical twins.
The experience of people working the night shift, who use blackout curtains to sleep during the day, would disagree.
Wow, I didn't know my own experience disagreed with me...
Or that during my childhood when my dad was swing shift, he was apparently a freak of nature too...
But that’s for a relatively highly regimented sleep cycle. If you slept and worked completely at your leisure, you might end up with one shorter sleep period at night, and one even shorter nap during the day. And without any day-night cycle at all, some people naturally adopt cycles of varying lengths.
Again, human variation is a big thing.
But an individual will change their sleep schedule as they age, which is another supporting point for what I'm saying.
Evolutionary biologists hypothesis that it was so out of an entire tribe of early hominds, at least some members were likely to be awake. It wasn't an inate guard duty rotation. But kids and middle age went to bed early, teens went to bed super late, and by then the elderly were waking up.
If something happened, someone screamed and everyone woke up. And the fires stayed lit all night.
I feel like I’d definitely break an ankle if I tried sprinting otherwise
Yeah, we played paintball even, but stopped because one guy ran straight off like a 6 foot mini cliff. A couple of us were chasing him and he just disappeared. Was freaky as shit like that scene from LotRs.
I also have to account for the fact that there was some light pollution
Yeah, I'm talking really hillbilly stuff, zero light pollution.
but in the darkest conditions that happen at sea apparently you can’t see your own hands.
A ship gives off a lot of light pollution, but even without that, between the water reflecting and nothing blocking light, it's brighter out there unless there's heavy clouds cover. And even then it's gotta be a lot of clouds and rough waves or else the light would still be refracting some.
Now a watertight compartment on a ship with the light switch on the outside?
Yeah, that's complete darkness. It's not just "can't see your hand in front of your face". It's the absolute and complete absence of light. That's total darkness.
“Full darkness” isn’t even a real thing in nature.
And
It’s not like climbing into a cupboard, shutting the door, and sealing all the cracks with duct tape.
So I thought it was pretty clear I meant that to get "full darkness" where you really can't see, requires extra steps to intentionally make it happen. Just that for the vast majority of human evolution, we weren't really capable of it, and would have no reason to even try.
We’re diurnal, and have eyes optimised to see maximum colour and detail instead of well in dim light (at least by mammal standards)
Human variation.
There's two main structures in our eyes.
Rods: take large amounts of any wave length of light
Cones: take in a very small amount of a specific wavelength and only that wavelength
Most of the area (like 95%) are rods. And there's a couple (usually three) types of cones.
Some people have more different types of cones, and can see more differences in color. Some have less types meaning less cones overall even.
But the eye won't just have more blank spots. So it fills in with more rods.
This is actually related to why the further away from the equator people got, the lighter their eyes got.
With longer variation in day/night cycle, it was advantages to let as much light in as possible. That outweighed the downside of too much light during the day, as that could be solved with hat brims, or that age old move where you make a visor with your palm.
By limiting the amount of light going to your rods, your cones get less "washed out" and that's how we get more detail/colors.
But even in a single population, there's going to be a lot of human variation. Rod/cone distribution has a high amount of variability even when genetics are steady. Genetics has a large effect, but it's not like the body always follows directions closely.
That's why there's "blue light filters" on electronics these days. That wavelength isnt included with moonlight/starlight.. maybe on a big full moon there's be some.
And why people prefer soft yellowish lights when relaxing and not the bright ass LEDs.
I mean, my night vision was always better than most...
But growing up as kids we'd be sprinting thru the woods playing tag at like 10pm summer nights, not a single electric light in sight
You're not going to recognize someone 100 yards away, but you're not walking around with your hands in front of your face to make sure you don't run into anything.
If you're under an open sky, or even a primitive shelter, you're not in complete darkness.
"Full darkness" isn't even a real thing in nature. It's hard to tell with light pollution, but even in the absolute middle of nowhere with no artificial lights, you're going to be able to see fairly well. Even with no moon, starlight isn't just an expression. And on a full moon it can be surprisingly "bright" if you're just out there for a while.
It's not like climbing into a cupboard, shutting the door, and sealing all the cracks with duct tape.
You may be used to needi g full darkness to sleep, but that's a learned habit. I guarantee if there was nothing you could do, it wouldn't take you long to adapt your "requirement" of total darkness.
If your lifespan was an hour, every generation that witnessed a sunrise or sunset would freak the fuck out and think the world was ending.
I've always thought of entropy like that, it seems one direction, but only because we're on a comparativly tiny timescale.
Used to subscribe to the "big crunch" theory that it'll just all start over. But the more Penrose and Hawking I read, the more I think the Big Bang just isn't that unique.
There's a lot of signs that the vast majority of existence is dark matter, and with how it interacts with regular matter, I don't think we have sequential big bangs like a single light slowly flashing. I think it's more like fireworks in the sky.
There's probably not anyway to travel through the dark matter to get to another "bubble", and even if we did, that bubbles laws of physics could be drastically incompatible with us.
Like, if you remember the Narnia books it's like that "main world" where it was just an infinite number of ponds and jumping into one shoots you out to some world world everything works better. I think The Magicians kind of ripped off the idea, and by now more people may be familiar with that then one of the least popular (but underrated) books in a children's series from ww2.
Entropy is functionally persistent, but only because everything we can see and interact isnt all there is. There could be multiple other bubbles of matter happening right now, it's just about what frame of reference we have.