Ethnic Cleansing and Human Evolution

Please pardon my recent radio silence. I evidently haven't mastered the art of simultaneously blogging and reporting for print, and I've been occupied with the latter this week. That's why this blog hasn't been updated since I blogged, well, about breaking my radio silence. Since then, I've been hard at work on a story about light pollution, which I hope will be ready to showcase in this space within a few days. In the meantime, let's talk about ethnic conflict and human evolution. (Disclaimer: What follows is more scientific hypothesis than journalistic fact. I welcome any data that confirm or refute what I'm about to suggest.)

It's not often that calls for ethnic cleansing relate in any way to human evolution. But I think I found one in a discouraging but beautifully written article about the historical roots of Kenya's current problems. The article shows how long-simmering conflicts over land ownership underpin much of the post-election violence currently seething across Kenya.

The Washington Post's Stephanie McCrummen, reporting from conflict-wracked Elmenteita, Kenya, wrote:

The family of former president Daniel arap Moi is similarly flush with fertile land, including a vast swath near this Rift Valley town, where preelection local radio broadcasts urged "the people of the milk," a reference to the Kalenjin [tribe], to "clear the weed," the Kikuyu [a rival tribe], according to a recent report by the International Crisis Group.

Now, I don't know much about the Kalenjin or the Kikuyu, but I do know that the former have traditionally been pastoralists, or animal herders, and the latter, farmers. I also know that conflicts between animal herders and farmers are nearly as old as the firmament. (Just think of the allegory of Cain, the farmer, and Abel, the shepherd.)

I suspect there's a link between the metonyms the violence-inciting broadcaster used—"people of the milk" and "the weed"—and the social and genetic histories of the two tribes he or she was alluding to.

Around the world, many people (like virtually all other mammals) are unable to drink milk as adults. Lactose intolerance, in a sense, is nature's default state. But lactose tolerance has evolved in many groups of people whose ancestors have herded mammals for centuries. These people have had a long-standing evolutionary incentive, so to speak, to be able to drink milk throughout their lives. So it makes sense that the pastoralist Kalenjins drink milk.

And the "weeds"? Well, that sure sounds like an unsubtle—not to mention offensive—reference to the way the Kikuyus, like Adam and Eve, by the sweat of their brows, learned long ago to coax a living from the soil.