Children born of interracial marriages have a higher IQ is the mother is white than if she is black. This -gests a maternal environment effect (prenatal and/or postnatal) rather than a genetic effect.
An alternative possibility-that there might be a difference in average parental intelligence in the two type’s marriages-cannot be completely ruled out because the parents’ IQs were not measured. But U.S. data indicate that the educational level of black husbands with white wives is about the same is that of white husbands with black wives.