I’ve read that East Asians developed slanted eyes or Epicanthic Folds as a way to adapt to snow blindness in the more snowy and colder regions of Asia, and I was wondering why Northern Europeans, specifically Germanic and Nordic people that lived in the colder regions of Northern Europe, didn’t develop the same genetic trait or at least something similar to it.
In: 973
Finer points of evolution aside, Europe has relatively mild weather and was heavily forested, so snow blindness wouldn’t really be an issue the way it would be in Mongolia. There’s also always been a lot of intermixing throughout the continent, so you wouldn’t expect to find a lot of unique traits in the north vs. south. For unique evolutionary traits to develop you need some kind of isolation from other populations. The Ural mountains and the Sahara are two of the biggest continental barriers which explains why people on either side of each look so different from one another.
Asking this question is like asking why a dice roll ended up at a 5 and not as a 6. Evaluation is random in that what traits happen vs what ones don’t is truly random. Of those random traits some of them will work, and therefore stick around and others won’t.
We don’t know for sure that East Asians developed slanted eyes or Epicanthic Folds as a way to adapt to snow blindness, but for the moment lets just assume that’s true. East Asians developed this trait, found it made them better able to see in the snow, and therefore were better able to survive. Since more of the people with this trait were surviving, eventually everyone who was alive had this trait.
Even though Europeans faced the same problem, they don’t chose to evolve based on the problems that they face. Rather we evolve and those evaluations either work and solve a problem making us more likely to survive, or they do not. You’re basically thinking of things backwards, you think it goes problem>solution but in reality it goes solution first.
It’s possible that this one trait was just lucky to become dominant in east Asia (with a small locus of dominance in parts of Scandinavia) and originated in Africa.
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