this post was submitted on 08 Jan 2024
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Today I Learned (TIL)

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[–] [email protected] 90 points 10 months ago (4 children)

And red/green color blindness isn't less colors, you get more shades of brown.

Which sounds shitty, but invaluable for hunters.

My dad legitimately didn't know what other people saw for "red" but he could spot a deer in the middle of the woods like it was neon yellow.

I believe the downside to tetracheomacy is less rods because the extra cones are taking up more space. Which I think translates to really bad night vision.

[–] garfaagel 23 points 10 months ago (1 children)

Cool! I had never heard about this theory for explaining color blindness.

[–] [email protected] 21 points 10 months ago (1 children)

There's very few things that are a flat negative evolutionarily.

Like sickle cell, in most of the world it's a significant disease. But if you live somewhere with malaria before modern medicine, then for 99.9999% of human existence, you'd be dead at a young age without sickle cell in those places.

Or how appendix bursting was worth the risk of retaining gut bacteria. Once we got clean water, the adaption of not having an appendix started to spread. Until modern surgery took out the negative evolutionary pressure so humans will be stuck with appendixes for ever now.

[–] [email protected] 3 points 10 months ago* (last edited 10 months ago)

I'm heterozygous for cystic fibrosis. It fucked my plans for having kids, cause I don't have vas deferens. (Most people who are heterozygous don't have any problems, but some men do with fertility). But apparently heterozygous people are more resistant to cholera and dysentery, since our cells hold onto water easier.

[–] [email protected] 19 points 10 months ago* (last edited 10 months ago)

According to wikipedia, tetrachromacy is caused by having having both normal vision and red-green color blind genes in different chromosomes, so some of the red or green cones end up being receptive to a wavelength between red and green. Rods don't sound affected.

Health line article doesn't mention the wavelength. Got me excited that it was infrared or something

[–] [email protected] 10 points 10 months ago (1 children)

Same with my dad. He said that the military liked red/green colour blindness for spotting camouflaged stuff.

[–] [email protected] 8 points 10 months ago (3 children)

This link is very interesting. Interesting for people that are colorblind, and interesting for people that are not.

[–] [email protected] 4 points 10 months ago

I could see 3 out of 4 of them but I'm not colour blind...

[–] [email protected] 3 points 10 months ago* (last edited 10 months ago) (1 children)

That's fun!! I am not color blind and was able with a lot of work to sort of see some of them. The easiest is the second one just squint and unfocus if you wanna try. The first one I couldn't get to work at all though

[–] [email protected] 2 points 1 month ago

I am colour blind and the first one was the easiest to see by far. My wife couldn’t make it out even when I showed her where the lines were.

[–] [email protected] 1 points 10 months ago

Great, I'm too color blind for the normal tests, and not color blind enough for this apparently. Fuckin dots man.

[–] [email protected] 4 points 10 months ago

This is how all super powers work... There is always a downside.