Edge.org / quote 2 of 4
Inheritability is not the inverse of mutability
Inheritability is not the inverse of mutability, and to say that the heritability of a trait is high is not to say that the environment has no effect because heritability scores are themselves affected by the environment. Take the case of height. In the rich world, the heritability of height is something like 80 per cent. But this is only because our nutrition is universally quite good. In places where malnutrition or starvation are common, environmental factors predominate and the heritability of height is much lower.
Similarly, a high heritability of academic performance is not necessarily a sign that education matters little. On the contrary, it is at least in part a product of modern universal schooling. Indeed, if every child received an identical education then the heritability of academic performance would necessarily rise to 100 per cent (because any differences could only be explained by genes). Looked at in this way, a high heritability of academic performance is not a right-wing belief but rather a left-wing aim. But try explaining that to a newspaper columnist on a deadline or a politician with an axe to grind.