In most of the world, the article explains, the gene that allows for the digestion of lactose switches off after childhood. But with the arrival of the first cattle herders in Europe some 5,000 years ago, a chance mutation that left it turned on provided enough of a nutritional leg up that nearly all of those who survived eventually carried it. In the post, the link is accompanied by a snippet of hate speech urging individuals of African ancestry to leave America. “If you can’t drink milk,” it says in part, “you have to go back.”
In an inconvenient truth for white supremacists, a similar bit of evolution turns out to have occurred among cattle breeders in East Africa. Scientists need to be more aware of the racial lens through which some of their basic findings are being filtered, Dr. Novembre says, and do a better job at pointing out how they can be twisted.