We are talking about averages. It has long been true that Black and White IQs differ by about a standard deviation. However, there is more overlap in the two distributions (bell curves) than there is difference.
There are Whites and Black who are geniuses and Whites and Blacks who are idiots. IMHO, Black culture reinforces the notion that it’s cool to be an idiot. From what I am seeing from Generation Y, that is increasingly common among Whites.
There have been studies of genetically-indistinguishable European populations as well—of roughly similar cultural and historical background and without severe nutritional difficulties, etc even within the same country—that also display huge variances of 1 standard deviation across different decades and locations, so I agree we should be extremely cautious about assuming that other ethnic IQ differences are innate rather than environmental.
We are talking about averages. It has long been true that Black and White IQs differ by about a standard deviation. However, there is more overlap in the two distributions (bell curves) than there is difference.
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never forget that Asian outperform whites by a significant amount, and that, more than anything else will make the 21rst century an Asian ascendry