Here is an example of why those interested in the history of economics such as Robert Dimand should take Rushton, or by extension, human biology and genetics, seriously. Ashkenazi Jews are a high IQ, economically successful group, that has also suffered from discrimination and persecution over the years. There are also certain genetic diseases which have a high incidence among this group. A group at the University of Utah has put forth a hypothesis that links these facts to natural selection for intelligence among this group. Albert Himoe Read the the paper here <http://homepage.mac.com/harpend/.Public/AshkenaziIQ.jbiosocsci.pdf> : This paper elaborates the hypothesis that the unique demography and sociology of Ashkenazim in medieval Europe selected for intelligence. Ashkenazi literacy, economic specialization, and closure to inward gene flow led to a social environment in which there was high fitness payoff to intelligence, specifically verbal and mathematical intelligence but not spatial ability. As with any regime of strong directional selection on a quantitative trait, genetic variants that were otherwise fitness reducing rose in frequency. In particular we propose that the well-known clusters of Ashkenazi genetic diseases, the sphingolipid cluster and the DNA repair cluster in particular, increase intelligence in heterozygotes. Other Ashkenazi disorders are known to increase intelligence. Although these disorders have been attributed to a bottleneck in Ashkenazi history and consequent genetic drift, there is no evidence of any bottleneck. Gene frequencies at a large number of autosomal loci show that if there was a bottleneck then subsequent gene flow from Europeans must have been very large, obliterating the effects of any bottleneck. The clustering of the disorders in only a few pathways and the presence at elevated frequency of more than one deleterious allele at many of them could not have been produced by drift. Instead these are signatures of strong and recent natural selection.