[Burkeman1]

Skin color and hair texture is largely a reflectin of climate. Caucasions and Asians have lighter skin due to UV radiation and the need to absorb more of it in Northern climes while Africans have dark skin in order to deflect excess UV radiation. Estimats range- but those who specialize in this area believe it took only about 20,000 years for dark skinned Africans who migrated to Europe to become "white". That is at least what I have read.

[AdmSmith]

Yes, and if you check the DNA of people from Eritrea/Ethiopia you can probably see that they went back to Africa after some time in "ME"/"Europe".

[blam]

"Estimates range- but those who specialize in this area believe it took only about 20,000 years for dark skinned Africans who migrated to Europe to become "white". That is at least what I have read."

Yup. Anthropologist Marvin Harris (RIP), thinks it could have been as recent as 10k years ago.