Actually, you're wrong about southern Europeans, and you show a lot of hubris when you claim you "know" why their complexion is what it is. I don't think anyone knows that, though almost certainly plain old evolution is a big part of it. Their complexions, by the way, almost totally overlap with those seen in other parts of Europe, even if the averages vary a bit. I'm of confirmed 100% Norwegian ancestry, and I am certain I could pass for a local in Messina or Marseilles. The Sardinians, for but one example, are the least mixed people in Europe. Look it up.

And I must add that every people deserves to continue to exist as a genetically distinct people, even if the current theory (which might be superseded by next Thursday's theory) says some traders passed through a thousand years ago.

The key concept here is racial separation -- the concept that makes conservatives and liberals alike want to either hide under the bed or explode in rage. The truth about racial separation is that it is necessary if evolution is to take place at all. Without racial separation, there could be no evolution. Life as we know it is the result of innumerable acts of past racial separation. It is essential.