| Nobody has ever claimed a 100% genetic basis of difference. The individual heritability of IQ is .5 to .8 for example Sub-Saharan diversity is a real thing, eg Bantu, Nilotic, Pygmy and Bushmen are extremely diverse (African Americans are not Pygny or Bushmen so not as diverse) But if you use cluster analysis on human genomes and ask it to divide humanity into 2 clusters, it divides humans into Sub Saharan Africans and everyone else. The key is selection not just randomness (most variation does little or nothing) you can't say eg "Africa is the most diverse therefore it will have the best adaptations for altitude" (that would be Tibetans, courtesy of interbreeding with Denisovians) The number of variants responsible for skin color is actually extremely small. It's why you can have such large variation between siblings. In contrast yes intelligence is highly polygenic. However, given sufficient sample sizes you can calculate genome wide association scores and work this all out. |
My understanding is that while we attribute much of inequality to bias in treatment, recent immigrants and their decedents vastly outperform comparable individuals with the same skin color.
To me, this indicates that much of the differences we observe are due to biases of past treatment, opposed to discriminatory treatment in the present.