I believe there is genetic proof that mankind today is actually one species with a common heritage. Inter-racial progeny would seem to bear this out.
The genetic science backing up the "out of Africa" claim is very suspect. Its claim to authenticity is protected by the very esoteic nature of the mathematical modelling of the genetic forms which its inventors have created. (I've got a BS in mathematics, and can't even follow what they're talking about.) Also, three of the principle authors of this theory are admitted Marxists, which, in my book, makes anything they say suspect.
This isn't an argument about speciation--I'm a believer in the idea that we all have common ancestral types, though not necessary of the Darwinian sort. It's a matter of which peoples on earth are able to establish and maintain certain level of civilizations, who shares common (and exceedingly ancient) cultural icons, etc.
The African people are different from Asians and Caucasians; to claim otherwise is to live in a fantasy world. There are differences between Australian aborigines and Africans. And etc. There are FEWER differences, essentially, between Asians and Caucasians.
It's not PC to say so, but everyone knows it instinctively, and I believe archaeological research is proving it out.
This isn't to claim anyone is "better" than anyone else, so let's avoid indignant posturing. We're just different. The differences are displayed every day.