« Quantitating liberalism | Gene Expression Front Page | The evidence against evolution »
February 20, 2004

Determinist, I?

Genetic determinist. Call it GNXP's Rule, all discussions that relate to the intersection of sociology & biology eventually seem to elicit an accusation or implication that GNXPers are "genetic determinists."

Genes set constraints and parameters. They load the die. But what they end up determining depends on both the gene in question and the context that the phenotype is expressed.

If you take two identical twins and beat one of them over the head periodically for a year during early infancy to the point where it exhibits brain damage-I freely admit that the intellectual capacities of said individual are not predominantly genetically determined. If you take a population of children from a small town and dose them with high levels of lead to the point where the vast majority become mentally retarded-I find it plausible that heritability of intellectual capacities will be lower in this population than otherwise.

We speak not of individuals, but of populations. We speak not of on-off dominant-recessive traits, but of continuous polygenic traits. We apologize to regular readers who have listened to this litany for the nth time, but our experience is that one can not repeat it enough ....

Posted by razib at 05:33 PM