It's the simple truth. There's six billion people, and among the lot of them there's less genetic diversity than there is in 60,000 chimps. We're inbred, by comparison. Obama's father is not American, or West African. He's East African, from Kenya. His mother is more likely to have West African genetics. IIRC East Africans differ from West Africans more than either do from Europeans, genetically. So from a genetic point of view, you have either three races there or one. Or possibly two races, with the white folks being a subgroup of one of them.