In the midst of an interesting post on IQ and Headstart, Mark A. R. Kleiman writes:
The more general point is that the ‘heritability’ of a trait is not a constant across environments, and that the attempt to parse all differences into an environmental component and a genetic component whose coefficients sum to unity — the basic project of The Bell Curve — is incoherent.
Now, I don’t seem to have a copy of The Bell Curve handy here (well, nowhere 30 seconds of looking uncovered), but I read it about three years back, when I was Charles Murray’s intern at AEI. And as I recall, this was a point that he himself made. That is, he argued that as access to a reasonably good education (the good environment) becomes more widely available, the heritability of IQ—the fraction of variation in intelligence explained by genetic factors—increases. So whatever else one might say about the book, he did get that right.
Update: Speaking of said internship… I just happened upon a photo album my ex-suitemate from that summer has up, which includes what may well be the most preposterously metrosexual picture of me ever taken.