It is easy to separate from cultural background.Take black children for example who were adopted by white parents.Their IQ continued to be low in the same levels with the average of black children raised by black parents.So it is genes which determine intelligence a truth that teachers know very well.
Contra arguments:
1.Studies dealing with kids raised together in institution are suggesting there are no interracial differences. Kids who's parents were caribic black or white showed that average IQ at age 4 was 103 for white kids, 106 for mixed kids, 108 for kids with both black parents.
2. If gens would be the main factor of interracial differences then kids who have one Caucasian and on African A as a parent would score same. Kids whose mother is white , father black had in average 9 points more than kids who's mothers were AfAm and fathers white. Explanation for discrepancy is that white mothers usually are providing more stimulative (better educated) environment than AfAm mothers.
3. Flynn, 1980, studied the IQ of few hundreds of German kids who's fathers were African americans and white American soldiers stationed in Germany. Average IQ for both groups is same (97), suggesting that race is not contributing to IQ.
4. Study from Scarr, 1977, dealing with proportion of european gens in African American population (as a result of mixing with white Ams) done in Philadelphia , 3000 kids participated, showed that relative proportion of white gens is not correlated at all with IQ, no differences found.
5. African american kids that were categorized high IQ using number showed that those kids had LESS white ancestors than general AA population who scored less on IQ test.
Those things are shifting responsibility for found differences from gens to environmental factors who seem to be more relevant for developing skills IQ tests are measuring.
it's not that simple to distinguish how much that quite small difference is a result of bad environmental factors, and how much it's a genetic thing.
It's true they are scoring in average 10 points less (which is quite small number btw.), but it's probable that differences are caused by life experiences rather than gens (for decades African american kids were raised in poor families, abandoned by fathers, with lousy education possibilities, in criminal neighborhoods)
I wonder what is the average IQ of people who judge others on IQ?
everybody is doing that. so i guess it's 100 ;)