Why is it that most other races such as Asians and Africans have almost uniformly black hair and black or dark brown eyes while whites have several hair and eye colours? I know there are a few minor exceptions such as some Australian Aborigional having blond hair for example.
This article suggests that it was a sexually selected adaptation due to unique factors in prehistoric Western Europe. Frankly, I find the author’s conclusions to be a little light on the evidence to be really satisfying.
You might as well ask, and with a lot more justification, why blacks are so much more diverse than other races in height.
Why is that more justified?
I don’t think the state of our understanding of the genetics of hair color is such that we can give a factual answer to the OP’s question. Other than: There have been more mutations that affect hair color among populations in and around Europe than in other places.
IIRC, though, the genes that control hair and skin color are not entirely independent of each other.
It’s all that Neanderthal admixture 
Indeed, a single gene mutation (on MC1R) is responsible for the majority of us who have red hair also having fair skin. I find it interesting that the combination of brown eyes and red hair is uncommon if one has fair skin considering that eye color isn’t thought to be linked to that gene.
Because height is a much more significant trait than eye color.
Well fist off, most White populations also have have almost uniformly black hair and black or dark brown eyes. Go to India or Libya sometime and try to find the person who doesn’t have black hair and black or dark brown eyes. The vast majority of White people have black hair and black or dark brown eyes just like the rest of humanity.
Some populations that we consider part of the nebulous “White” population have some people with variations on black hair and black or dark brown eyes, but that isn’t in any sense typical of all White people or all White populations.
As far as eye colour goes, it’s simply the overall lack of pigmentation. In the same way that you can draw on white paper with pencils of any colour, but you can’t raw on black paper with them. So you can produce a refractive pattern leading to green eyes in a tissue lacking melanin, but you can’t produce a refractive effect that will mask melanin. As far as we can tell it’s just coincidental to the overall lack of pigment. Strip out the masking pigments and the refractive patterns of the eye become visible.
Beyond that, I suspect that the only reason that “Whites” have more diversity in those traits is because we define “White” as a population with a diversity of someone with those traits. If we defined “White” geographically or genetically or based on skin colour or in any way at all aside from via those traits then I doubt they would have greater diversity of those traits.
There’s no scientific basis for this classification scheme. We might just as easily define “White” as “western European” or “with a skin tone lighter than X” and then we would find that those eye and hair colours are common amongst people who are not White.
IOW it is perfectly circular. You might just as well ask why all “Black” people have dark skin. If you define a group based upon certain traits, then of course they will have that trait.
That statement is so subjetcive as to be meaningless.
If you were considering the incidence of cataracts or visual performance in high light environments or the use of prosthetic contact lenses, then height would be completely irrelevant and eye colour would be highly significant.
The only way that you can possibly conclude that height is “more significant” than eye colour is if you first reject the multitude of criteria by which eye colour is *more *significant.
And the subsequent follow-up, though that one doesn’t touch on the variations among Caucasians so much as how we tend to focus on attributes that vary more widely in our own racial group.
From a genetic predisposition to a particular height or eye color, I think height is more likely to be influenced by outside forces. Childhood nutrition, or lack of it, would make a difference.
Obviously, it’s due to the Reptilians’ successful program to breed Northern Europeans into a submissive population.
Free David Icke!
I’m wondering why the OP, an American, uses the British spelling convention for the word “color”.
It’s Qin. ISTR that he’s used that sort of affectation before.
Yeah. One of the fuzziest parts of this question is, “who are you calling ‘white’?” IMHO the definition of “white” has been deliberately (if not consciously) expanded several times. There was a time when Italians were not considered “white” but now they are. Any time you keep adding new populations to a given definitoin, you’re going to see diversity within that definition.
If we use the old style definition of “Caucasian” that includes the Europe, Middle East, North Africa, India, Iran and that area of Asia, you’re still going to have a population with more eye color variation than other populations.
Well, the question referred to “whites,” which isn’t necessarily the same thing as “Caucasian.”
Can we sidestep the “race” issue? Let’s reformulate the question:
Why do some human populations have a greater diversity of eye and hair colors than others?
I don’t know the answer, but I do know that hair-color genetics is complicated. Using mine own family as an example, both me (mixed European and Native American ancestry) and my spouse (pure Korean) have black hair. Our kids have medium-brown hair. Although my parents had black hair, I have a blonde sister and a red-headed uncle. So I have light-hair genes, they’re not expressed in me, but are expressed by my children. It’s obviously not a simple dominant-recessive allele pair.