Today I Learned (TIL)

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TIL about Tetrachromacy, a condition which lets you see more colors. Normal people can see about 1 million colors, while tetrachromats may see up to 100 million. Up to 12% of women may have it. (www.healthline.com)

submitted 10 months ago by garfaagel to c/[email protected]

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[–] 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.