As some of you already know, Henry and I have put forth the hypothesis that the observed high intellectual achievement of Ashkenazi Jews is a result of natural selection for intelligence over the Middle Ages. We think there’s a pretty good case. One important supporting fact is that high Ashkenazi intelligence shows up everywhere they live. You see it in Russia, the US, Latin America, Israel, etc. It doesn’t spring from a single cultural milieu: you saw it in Jewish kids raised in turn-of-the-century Vienna, in Israeli kibbutzes, in Bronx tenements, and in Stalinist Russia. It’s not a consequence of Talmudic study – you see the same results in religious and irreligious people of Ashkenazi descent.
Interestingly, other ethnic groups show a similar pattern. Those that exhibit high levels of intellectual achievement in one country do so in others. Chinese do well in every society, even if they arrived as illiterate tin miners, as they did in Malaysia. Swedes in the h0meland score like their cousins in Minneapolis. Sub-saharan Africans do poorly in every country they inhabit. This suggests that genetic factors may be the main general cause of observed intergroup differences in intelligence and academic achievement. The selective pressures that caused these differences may not be as easy to figure out as in the Ashkenazi case, particularly if they acted over tens of thousands of years.
As Neil Risch forcefully put it, in an interview with Karen Kaplan on our paper about Ashkenazi Jews, “What are their theories about those on the opposite end of the spectrum? Do they have genetic theories about why Latinos and African Americans perform worse academically?” A truly perspicacious question – to ask it is to answer it..