There have been a variety of responses to my column in The Crux on race. To be fair, because the audience for The Crux does not consist of genome nerds I engaged in some first approximations which some readers have taken objection to. For example, the genetic architecture of blue vs. brown eye inheritance is ‘quasi-Mendelian,’ with ~75 percent of the variation in Europeans on this trait attributable to variation in the region of the HERC2 and OCA2 genes. But I thought, and still think, that a rough re-characterization of the trait as a recessive one with a monogenic Mendelian inheritance pattern can be justified for didactic purposes (just like one can justify the idea that whole human genomes have been sequenced, even if there are large gaps, and known errors in regions of repeats).
But the comments over at Richard Dawkins’ website have been rather amusing as a whole. Some people were patronizingly pedantic, and I don’t have time respond in detail (the real response would be: read my blog!). But some comments are easy to answer:
I’d like to hear Dawkins’ response to this, I’ve read all of his books and he’d surely disagree with the author of that article.
Easy. He discusses race in The Ancestors’ Tale (a book the commenter claims to have read):
Hominin increase in cranial capacity, courtesy of Luke Jostins
A few years ago a statistical geneticist at Cambridge’s Sanger Institute, Luke Jostins, posted the chart above using data from fossils on cranial capacity of hominins (the human lineage). As you can see there was a gradual increase in cranial capacity until ~250,000 years before the present, and then a more rapid increase. I should also note that from what I know about the empirical data, mean human cranial capacity peaked around the Last Glacial Maximum. Our brains have been shrinking, even relative to our body sizes (we’re not as large as we were during the Ice Age). But that’s neither here nor there. In the comments Jostins observes:
The data above includes all known Homo skulls, but none of the results change if you exclude the 24 Neandertals. In fact, you see the same results if you exclude Sapiens but keep Neandertals; the trends are pan-Homo, and aren’t confined to a specific lineage….