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[–] MinorLeakage 2 points 22 points (+24|-2) ago 

Blue eyes aren't actually blue. They're just brown eye genes that don't work, so you just don't produce melanin in your eyes. They look blue for the same reason water and the sky look blue.

That's why it is "recessive". If you get a single working copy of the gene, your eyes wont be blue.

I'm not sure if hair is the same thing, but it's probably something similar. So the likeliest answer is that whatever advantage is gained from lack of melanin in your skin (probably vitamin D in northern extremes), also provides some advantage for your eyes (maybe snow blindness?).

The other possible answer is sexual selection.

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[–] cyclops1771 0 points 9 points (+9|-0) ago 

When I had my eye made, the ocularist said that the iris consists of layers of silver and gold streaks, emanating from the pupil out in a 'starburst' pattern. Brown eyes have more layers of gold than silver, blue eyes have more silver than gold, and green eyes are roughly even.

I have ZERO idea if this is true or not, but as I watched him make the prosthesis, that was how he painted it. Not sure why he would make up that story and then tell us that.

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[–] MinorLeakage 0 points 3 points (+3|-0) ago 

I'm not exactly sure, as I'm no expert. But I think your doctor was maybe explaining how he would mimic the coloration?

Here's a decent article on wikipedia (they can still okay for non-political subjects...) that actually disproves some of what I said earlier. But it does agree with (most) of what I said about blue eyes, in that it's structural, not pigmentation. The only pigment human eyes use is melanin, which ranges in color from brown to black depending on some other factors.

The appearance of blue and green, as well as hazel eyes, results from the Tyndall scattering of light in the stroma, a phenomenon similar to that which accounts for the blueness of the sky called Rayleigh scattering.[5] Neither blue nor green pigments are ever present in the human iris or ocular fluid.[3][6] Eye color is thus an instance of structural color and varies depending on the lighting conditions, especially for lighter-colored eyes.

https://en.wikipedia.org/wiki/Eye_color

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[–] CheeseboogersGhost 0 points 2 points (+2|-0) ago  (edited ago)

TIL why your name is Cyclops. One-eyed prick haha ;)

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[–] Jimbonez_Jonez 0 points 0 points (+0|-0) ago  (edited ago)

Had my eye made

I'll bite. Why did you have to get an eye made?

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[–] Itsdone63 0 points 3 points (+3|-0) ago 

I recall hearing that we all have blue eyes underneath and there is an operation available to remove the melanin and make them blue

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[–] MinorLeakage 0 points 4 points (+4|-0) ago 

Based on something I just read, it seems like it should be possible. All the melanin is in one layer, at the very back of the iris. But it seems like a really bad idea to risk losing your eye-sight just to have prettier eyes.

https://en.wikipedia.org/wiki/Iris_pigment_epithelium

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[–] seeker 0 points 2 points (+2|-0) ago 

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[–] Dalai_Llama 0 points 3 points (+3|-0) ago  (edited ago)

To be honest, I think that these lack of protein characteristics like blue eyes and blonde hair arose from more restrictive mating pools. I think that geographic isolation leads to an accumulation of recessive characteristics. A potential case in point being the Irish. Iceland has a population with many recessive characteristics also.

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[–] MinorLeakage 0 points 2 points (+2|-0) ago 

Absolutely. I think it's probably a combination of all of the above, with some playing a larger role and some less-so. There's even a decent chance that literal eugenics played a role. Some older European cultures were well known for killing babies if they didn't meet very specific criteria (size, weight, proportionality, etc).

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[–] Commie_Meta 0 points 0 points (+0|-0) ago 

What you are taking about is the founder effect, where a trait can become common if it occurs in a founder of a small population that later grows. An example of this is the increased frequency of Hirschsprung disease in the Old Order Mennonites.

This turns out to not usually be the case with human coloration. For example, there are six different common mutations that cause most red hair in Ireland, and a few less common ones. Most (all?) of them affect the type 1 melanocortin receptor, and the DNA have been sequenced. That implies a large population with a strong reproductive advantage for red hair and freckled pale skin.

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[–] Nalbarcam 0 points 1 points (+1|-0) ago 

sexual selection isn't as dominant a factor, since blue eyes are recessive, you can't always predict which children will have blue eyes and which wont

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[–] MinorLeakage 0 points 0 points (+0|-0) ago 

I completely agree that it isn't the dominant factor. It still might play some role in selection though. I like blue-eyed girls, and that will certainly increase my offspring's chance of having blue eyes (provided I also carry the gene, of course).

I was thinking more about hair color when I said that, though. And I really don't know what factors cause different hair colors, or what pigments are involved.