Phil Rushton and colleagues at the journal Personality and Individual Differences continue to push the the theory that genes explain the worldwide correlation between skin tone and important behaviors…
As Razib Khan has explained on this blog, pleiotropy as the explanation of these correlations simply does not work. So what plausible theories remain? Any ideas?
Citing some other research, I suggested that national IQ differences probably mediated the correlation between skin color and national K differences. This conjecture was partially borne out by Meisenberg and Woodley’s recent findings. Though, net of National IQ skin color is still a significant predictor of National K.
However, meta-analysis does not support an association between g and K at the individual differences level (Woodley, 2011a). What then could account for this ‘‘Rushton paradox’’?
One possibility is that at the individual differences level, g genes assort independently with K genes, and became correlated at the inter population level because selective pressures favoring higher g also favored higher K. A second possibility is clinal variation. As Sub Saharan Africans exhibit low g relative to other populations, any trait that systematically differs between Africans and non-Africans would therefore become incidentally correlated with g at the population level. A third possibility is that because both K and g are, in part, dependent upon environmental conditions, poor environments favoring fast life history might also inhibit g (Figueredo, 2009). A fourth possibility is that at the level ofinternational comparisons,IQ tests lose their g-loadings, such that national differences become accentuated by the Flynn effect. This suggests that effort allocation into the development of specific abilities rather than differences in levels of g may partially account for the association between national intelligence measures and national K (Woodley, 2011b, in press)….
[...] The results show that K can be operationalized at the country level with variables that conform to current understanding of this construct. However, the relationship between country-level g and country-level K, and especially between country-level K and individual-level K, require further investigation. Evolutionary conditions appear to be plausible contributors to the current worldwide distributions of both traits.
(BTW, You can read Templer’s overly effusive summary of Rushton’s work on the general factor of personality and national K differences, here:
Templer, D. I. Rushton: The great theoretician and his contribution to personality. Personality and Individual Differences (2012), http://dx.doi.org/10.1016/j.paid.2012.04.038)