Richard Nisbett has the most thorough trashing of research claiming a link between race and IQ I’ve seen yet.
For the poor, a group that includes a substantial proportion of minorities, heritability of I.Q. is very low …
Even when a trait is highly heritable (think of the height of corn plants), modifiability can also be great (think of the difference growing conditions can make).
… Tested in later childhood, the German children of the white fathers were found to have an average I.Q. of 97, and those of the black fathers had an average of 96.5, a trivial difference.
… when a group of investigators sought out the very brightest black children in the Chicago school system and asked them about the race of their parents and grandparents, these children were found to have no greater degree of European ancestry than blacks in the population at large.
… A superior adoption study — and one not discussed by the hereditarians — was carried out at Arizona State University by the psychologist Elsie Moore, who looked at black and mixed-race children adopted by middle-class families, either black or white, and found no difference in I.Q. between the black and mixed-race children. Most telling is Dr. Moore’s finding that children adopted by white families had I.Q.’s 13 points higher than those of children adopted by black families.
…Within each race, prior knowledge predicted learning and reasoning, but between the races it was prior knowledge only that differed.
… That environment can markedly influence I.Q. is demonstrated by the so-called Flynn Effect. … in the Western world as a whole, I.Q. increased markedly from 1947 to 2002. In the United States alone, it went up by 18 points. Our genes could not have changed enough over such a brief period to account for the shift; it must have been the result of powerful social factors.
… In fact, we know that the I.Q. difference between black and white 12-year-olds has dropped to 9.5 points from 15 points in the last 30 years — a period that was more favorable for blacks in many ways than the preceding era.
… Most important, we know that interventions at every age from infancy to college can reduce racial gaps in both I.Q. and academic achievement, sometimes by substantial amounts in surprisingly little time. This mutability is further evidence that the I.Q. difference has environmental, not genetic, causes. And it should encourage us, as a society, to see that all children receive ample opportunity to develop their minds.