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June 11, 2003

As the Germans did....

Over at Tacitus godless & I have been having a little dialogue with dissenters from the position that GNXP offers a different and valid viewpoint than normally mooted in "respectable" circles. In any case, one of the commenters brought up the Eyfurth study that showed that black-white mixed children in post-World War II Germany had about the same IQs as white children whose fathers were also servicemen. The study is very interesting and suggestive, because it contradicts the Minnesota Transracial Adoption Study that showed interracial twins adopted who were of mixed-race had IQs between that of black and white adoptees.

Jensen in The G Factor has a few quick responses:

  • The fathers' IQs are not accounted for, and it could be that both groups of servicemen, black & white, were not representations of the mean in their parent populations. Jensen notes that 30% of blacks vs. 3% of whites were rejected during preinduction because they failed mental tests.
  • Factors that influenced assortive mating were not tracked. For instance, low SES German women might have had equal preferences for high IQ black officers and low IQ white privates because intelligence could have overcome racial bias in the former case while there was a preference for the latter because they understood that their children might be less ostracized by society if they were not racial minorities.
  • The tests were taken during pre-adolescent years when correlation between IQ scores and genotype is lower than in later years.
  • Heterosis, or hybrid vigor, could have bridged some of the gap.

In any case, let's ignore these factors, and address the topic. Flynn, of the Flynn Effect fame, suggests that something in American society (prejudice, racism, etc.) might be influencing parents to treat their black adoptive children differently than they would white children. And yet it seems that if this is the cause than though situation is not totally analogous (white biological mothers of mixed-race children), we should look toward post-World War II Germany to solve some of the problems America has in socializing its black youth [1]. Additionally, we might also investigate how white parents treat their adopted Asian children, because these youth display no ill effects of racism, but rather, often score higher on IQ tests than white children.

Also, check out godless' last comment over at Tacitus' thread....

[1] I do not by this suggest that we should institute a total racial state, liquidate our Jews, and prepare to deal with a massive invasion by the civilized nations that will destroy the heart & soul of our volk to purge our racist souls!

Posted by razib at 04:48 PM




"The study is very interesting and suggestive, because it contradicts the Minnesota Transracial Adoption Study that showed interracial twins adopted who were of mixed-race had IQs between that of black and white adoptees"

Actually it doesn't contradict the MTAS which found similar results for mixed-race kids raised in white homes and tested at that age:

"An interesting parallel to this work is our longitudinal study of interracial adoptees. At the average of 7 years, the African-American adopted children scored 106.1 on IQ tests. By the average age of 18 however, their IQ scores had declined to 96.8. Children with one White and one Black parent scored, on average, 109.0 at age 7 and 98.5 at age 18; children with two Black parents (and later adoptive placements) scored 96.8 at age 7 and 89.4 at age 18..."

So the WWII results were the same as the MTAS, it's just that the Eyfurth study never tested the same cohort for post-adolescent results. BTW, that's Sandra Scarr speaking in the quote, from the journal Intelligence. I think I'll let her finish [pay attention to what she says in the second paragraph, there is a lot of patterned evidence of this nature that points to a genetic component to this familiar gap.]:

" ...The test performance of the Black/Black adoptees was not different from that of ordinary Black children reared by their own families in the same area of the country. My colleagues and I reported the data accurately and as fully as possible, and then tried to make the results palatable to environmentally committed colleagues. In retrospect, this was a mistake. The results of the transracial adoption study can be used to support either a genetic difference hypothesis or an environmental difference one (because the children have visible African ancestry). We should have been agnostic on the conclusions; Art would have been.

A less recognized line of research, and one with great implications for developmental psychology, is Art's use of younger White children to model the test performance of older Black children. By showing that response and error patterns of Black children matched, on average, those of White children two years younger, Art did more than challenge the test-bias literature. He showed that differences in test performance among age-matched White and Black children can be most simply explained as differences in rates of mental development. The implicit analogy to physical growth is powerful: Slower growth rates over the same length of time lead to lesser final attainments, whether one is speaking of height or of intelligence. The implications of these studies are truly frightening... [all bold mine]

Posted by: Jason Malloy at June 11, 2003 06:00 PM


"I do not by this suggest that we should institute a total racial state, liquidate our Jews..."

Yeah, the key word was 'post-World war II' Germany. ;)

Posted by: Jason Malloy at June 11, 2003 06:10 PM


you should append my post malloy...don't be shy :)

Posted by: razib at June 11, 2003 09:25 PM


The Eyfurth study is now over four decades old. Somebody should try to replicate it.

Posted by: Steve Sailer at June 11, 2003 10:20 PM