Ashkenazi intelligence

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Ashkenazi intelligence refers to a controversial theory asserting the higher general intelligence of Ashkenazi Jews, the Jews of Central and Eastern European origin who are the descendants of Jews who settled in the Rhineland beginning about the year 800. Many anthropologists are critics of claims that intelligence differs among races, contending that while racial categorizations may be marked by phenotypic traits, the idea of race itself, and actual divisions of persons into races, are social constructs.[1][2][3][4] [5][6]

Contents

[edit] Psychometric findings

Psychometric research has found that Ashkenazi Jews have the highest mean score of any ethnic group on standardized tests of general intelligence, with estimates ranging from 7 to 12 points above the mean IQ of the general European population at 100, which ranges from 107 for Germany to 90 for Croatia according to Richard Lynn's estimates for 2006.[4] These studies (see references) also indicate that this advantage is primarily in verbal and mathematical performance; spatial and visual-perceptual performance is average. Besides being controversial, this work relies on existing studies "of questionable validity."[7]

However, some statistic data on Israel, where roughly 50 percent of its Jewish population is composed of Ashkenazi immigrants from Europe or their descendants, shows that Israel achieves lower average IQ scores than countries of Europe or East Asia (Israel 94, England 100, Hong Kong 107). See also IQ and the Wealth of Nations. Israel, however, is multiethnic, with not only Jews of diverse backgrounds, but also a sizable (20 percent) non-Jewish population.


Source Sample sizes. Number of Ashkenazi Jews tested. Average IQ Ashkenazi Jews in USA and/or UK
Backman 1972 1236 107.8 verbal IQ
Backman in present study 150 107.5 crystallized IQ
Lynn Estimated 103.5 Ashkenazi Jews in Israel
Storfer Suggested IQ 112
Bachman 1970 Lesser than 100 112.8
Herrnstein/Murray 1994 59 112.6

[edit] Cochran et al.

The 2005 study Natural History of Ashkenazi Intelligence[8] by Gregory Cochran, Jason Hardy, and Henry Harpending at the University of Utah noted that European Jews were forbidden to work in many of the common jobs of the Middle Ages from 800 to 1700 CE, such as agriculture, and subsequently worked in high proportion in professions such as finance and trade, some of which were forbidden to non-Jews by the church. Those who performed better are known to have raised more children to adulthood, according to Cochran et al., passing on their genes in greater proportion than those who performed less successfully.[9]

Cochran et al. hypothesized that the eugenic pressure was strong enough that mutations creating higher intelligence when inherited from one parent but creating disease when inherited from both parents would still be selected for, which could explain the unusual pattern of genetic diseases found in the Ashkenazi population, such as Tay-Sachs, Canavan disease, Gaucher's disease, Niemann-Pick disease, Mucolipidosis type IV, and other lipid storage disorders and sphingolipid diseases.[10] Some of these diseases (especially torsion dystonia) have been shown to correlate with high intelligence, and others are known to cause neurons to grow an increased number of connections to neighboring neurons.[11]

Reviews of the controversial paper have been largely negative, with critics claiming the argument to be far-fetched and unsupported by direct evidence.[10] Many genetically isolated human groups have faced multifarious adaptive pressures one could cherry pick to justify currently exhibited group traits.[12]

[edit] Other theories

  • Jews settling in the Rhineland were from the beginning mostly moneylenders and merchants, as well as rabbis. A biological (hereditary) explanation for high Ashkenazi IQ may be that modern Ashkenazi Jews are descended mostly from the several thousand Jewish settlers that belonged to occupations that one author claims are "far more highly selected for intelligence." This self-selection may also explain why Ashkenazi Jews have significantly higher IQ scores than Mizrahi Jews. An environmental (cultural) explanation for high Ashkenazi IQ is that since it was forbidden for Christians to take interest and money-lending, Jews took the opportunity and developed into a relatively wealthy social group, which traditionally can afford higher education to their children. The extent to which intelligence is hereditary (determined by genes) remains a controversial subject.[5]
  • Talent in the study of Torah traditionally contributed to one's social success in Jewish communities; those more lacking in the capacity for such study were perhaps more prone to assimilate into general culture, thereby raising the average intelligence of the given community. (Murray 2003)
  • European Jews' history of persecution selected for high intelligence, leaving a positive effect on the hereditary component of their IQ.[13]
  • Persecution led Jews to embrace education as a transportable asset, to better adapt to novel surroundings.[6]

[edit] See also

[edit] Notes

  1. ^ Thompson, William; Joseph Hickey (2005). Society in Focus. Boston, MA: Pearson. 0-205-41365-X. 
  2. ^ AAPA Statement on Biological Aspects of Race American Association of Physical Anthropologists "Pure races do not exist in the human species today, nor is there any evidence that they have ever existed in the past."
  3. ^ Palmie, Stephan (2007) "Genomics, Divination, 'Racecraft'" in American Ethnologist 34(2): 214
  4. ^ Mevorach, Katya Gibel (2007) "Race, Racism and Academic Complicity" in American Ethnologist 34(2): 239-240
  5. ^ Daniel A. Segal 'The European': Allegories of Racial Purity Anthropology Today, Vol. 7, No. 5 (Oct., 1991), pp. 7-9 doi:10.2307/3032780
  6. ^ Bindon, Jim. University of Alabama. "Post World War II". 2005. August 28, 2006.
  7. ^ Barnett, Susan M. and Williams, Wendy (August 2004). "National Intelligence and the Emperor's New Clothes". Contemporary Psychology: APA Review of Books 49 (4): 389–396. 
  8. ^ Natural History of Ashkenazi Intelligence
  9. ^ The Jews rarely married outside of their faith, creating a reproductively isolated population in which, in the statistical models of Cochran and his co-authors, this pressure would be able to influence gene frequency over nine centuries and 35 generations.
  10. ^ a b Wade, Nicholas. Researchers Say Intelligence and Diseases May Be Linked in Ashkenazic Genes, The New York Times, June 3, 2005. Retrieved February 12, 2007.
  11. ^ Patients with torsion dystonia (relatively common in Ashkenazi Jews), for example, are reported to have an average IQ of 122.
  12. ^ An account of Gould's "just-so" stories critique, especially applicable to the Cochran's speculative sources of Ashkenazi intelligence.[1]
  13. ^ See the NYTimes coverage for more information.[2] Cochran et al. 2005 is forthcoming in Cambridge's Journal of Biosocial Science. [3]

[edit] References

1. Cochran, Gregory; Hardy, Jason; and Harpending, Henry (2006): "Natural History of Ashkenazi Intelligence" (PDF). Journal of Biosocial Science 38(5):659-693 SEP 2006.

2. Herrnstein, R.J. & Murray, C. (1994). The Bell Curve: Intelligence and Class Structure in American Life. New York: Free Press.

3. Lynn, R. and Longley, D. (2006). "On the high intelligence and cognitive achievements of Jews in Britain." Intelligence, 34, 541-547.

4. MacDonald, K. (1994). A People That Shall Dwell Alone. Westport, CT: Praeger.

5. Murray, Charles (2003). Human Accomplishment: The Pursuit of Excellence in the Arts and Sciences, 800 B.C. to 1950. HarperCollins.

6. Storfer, M.D (1990). Intelligence and Giftedness: Contributions of an Early Environment. San Francisco: Jossey-Bass.

[edit] External links