eli5: If more melanin is advantageous in warm climates, why is less of it advantageous in colder climates? Wouldn’t darker skin still be most advantageous in cold climates where it might occasionally be hot?

Question

eli5: If more melanin is advantageous in warm climates, why is less of it advantageous in colder climates? Wouldn’t darker skin still be most advantageous in cold climates where it might occasionally be hot?

In: 1641

Answer 1

OP, you might be confusing heat with radiation from the Sun? What I’ve read as hypotheses about how European peoples “became pale” (if the theory on all early human migration originating from the prehistoric river valley civilizations and/or Africa is the one we’re going by for how physical differentiation/adaptation of human traits developed) is that it was something that occurred through a long process of evolutionary advantage having to do with vitamin D production/storage. Anyway, with the fact that many humans coexist with or live in the context of modern engineering and agriculture, concepts like “biological advantage” are basically moot.