Yeah, Watson again. And this is also related to the gender gap thread. This sums up some of the data reasonably well.
http://slate.com/id/2178122/entry/0
Evolution forced Christians to bend or break. They could insist on the Bible’s literal truth and deny the facts, as Bryan did. Or they could seek a subtler account of creation and human dignity. Today, the dilemma is yours. You can try to reconcile evidence of racial differences with a more sophisticated understanding of equality and opportunity. Or you can fight the evidence and hope it doesn’t break your faith.
Either you believe in evolution - in the sense of being convinced that it is a good explanation and likely to be something that is actually happening, and therefore certain consequences should be expected - or you do not. Either you believe human beings are material creatures, and thinking is a consequence of the physical hardware and is affected by said hardware’s characteristics, or else you believe in magic.
One thing that has definitively been established (via twin studies and the like) is that no amount of nurture effects can change IQ more than a few points from its “default” setting for any given person, and that only temporarily. If it is vitally important to your view of justice and humanity that all people should be able to reach the same potential in terms of thinking ability, fine, but don’t pretend that’s anything other than ideology.