When I was reviewing the paper on skin color and ethnic ancestry a few days ago I saw a peculiar figure in a related paper which I thought I would highlight. The paper is Skin pigmentation, biogeographical ancestry and admixture mapping. The samples were 232 African and African-American individuals living in Washington, D.C., 173 British African Caribbean persons, and 187 individuals of European-American ancestry living in State College, Pa. The goal was to compare the ancestry of individuals to see how it related to their complexion. The African ancestry of these populations was:
African Americans Washington D.C. 78.7%±1.2%
African Caribbeans Britain 87.9%±1.1%
European Americans State College, Pa. 0.7%±0.9%
The European ancestry was:
African Americans Washington D.C. 18.6%±1.5%
African Caribbeans Britain 10.2%±1.4%
European Americans State College, Pa. 96.1%±1.6%
The Native American ancestry was:
African Americans Washington D.C. 2.7%±1.4%
African Caribbeans Britain 1.9%±1.3%
European Americans State College, Pa. 3.2%±1.6
Below is a figure with "Melanin Index" on the Y axis and ancestry proportion on the X.
The R-squared refers to the amount of variation of the Melanin Index which can be explained by the ancestry on X. Black Americans with more African ancestry are darker skinned on average as a population, but the relationship is imperfect. I pointed to some reasons earlier for why this is. In any case, I'm not interested in the black samples. Look at the "European Americans." At first I assumed it was an interesting coincidence that the three outliers all had the mean European American complexion. That is, though they were only 50-60% European in ancestry it turned out that they were just about the median complexion for northwest Europeans.
But thinking about it more, I realized that anyone with that much non-European ancestry who did not look European would not be in that sample. In other words, they would not identify as white because American cultural norms simply would not allow it. The same size here is 187, so those 3 outliers are only a small proportion. I think that a plausible hypothesis is that some of these are the outcomes of "extra-pair paternity events," if you know what I mean (I naturally don't know the frequencies around State College, though these were likely Penn State students from elsewhere). In any case, an interesting point here is that gene flow across populations can occur even if there are social norms discouraging it if the "packaging looks right."
I'm not sure that 'extra-pair paternity events' is the best explanation for these outliers. As an example my son could easily be described as a 'mixed race white' - one parent is of European ancestry and the other is Asian. My son could easily pass as white amongst his 100% European classmates.
Was something done in this analysis to exclude those of european-asian backgrounds?
Contrary to popular belief due to miseducation, "white genes" are not the weakling genes of the human race. Mixed-race populations such as the Melungeons and Redbones are now nearly all white-identified. White-identified Creoles (such as Anatole Broyard) are silenced in favor of black-identified Creoles. Hispanics who intermarry with "real whites" bring the dreaded "black blood" with them into the "white race." Traditionally, different states formally allowed different degrees of "Negro ancestry" into the white population. However, scholars of mixed-race history have found that "performing whiteness" (exercising the rights of whites and social acceptance by other whites) was of even more importance than degrees of "blood."
A.D. Powell, former columnist for the web sites "Interracial Voice" and "The Multiracial Activist," is the author of "Passing" for Who You Really Are: Essays in Support of Multiracial Whiteness.