Stephen J. Gould said that “there’s been no biological change in humans for 40,000 or 50,000 years.” Gregory Cochran and Henry Harpending beg to differ and, in “The 10,000 Year Explosion,” point to evidence for a recent acceleration in human evolution (e.g. lactose intolerance) ((Fans of the Coen brothers will recognize the title of this post as a kind of a quote from one of their films, and will indulge me. Others, not, on both counts. So be it.)) and blame it on agriculture. Not everyone agrees. I can’t help finding the idea of the end of genetic change somewhat preposterous, a priori. ((Culture doesn’t replace genetic change, “culture constrains genetic changes.”)) But one must find data. Check out the interview with Cochran at 2blowhards. ((It’s in several parts, and some of the internet buzz on the book is rounded up in this installment.)) What all this means to us here, of course, is that when we assess variation in the nutritional value of agrobiodiversity, we need to remember that that value may differ among human individuals and populations.
Introgression from Neanderthals as a source of adaptive variation is a fascinating hypothesis; I like the idea that Homo sapiens have benefited from alleles from wild relatives. Recent adaptation and all the signs of positive selection in human population following the shift to agriculture based diets expose the fallacy of proponents of the Paleolithic diet (nutrition science’s equivalent to Pop-EP ), not to mention all the doctor Atkins disciples out there.