chanda chisala, formerly a visiting fellow at both stanford and the hoover institution, and who is originally from zambia, has written a blogpost at unz.com that’s generating a lot of interesting discussion: The IQ Gap Is No Longer a Black and White Issue.

much of the discussion surrounds whether or not africans that have recently migrated to the u.s. or the u.k. are representative of their populations, or if they’re self-sorted elite groups (i’d guess the latter is probably correct — see dr. thompson’s comment regarding this issue), and, more technically, how regression to the mean works (see here and here) which relates to the question of to what mean are the iqs of the children of african immigrants regressing — a general african mean or are different african groups regressing to different means (see here and here)?

i don’t have the answer to ANY of those questions (doubt i ever will have much insight into them), nor do i think that anyone DOES have good answers to those questions. yet. Further Research is RequiredTM.

i do want to highlight and comment upon something chisala had to say in the comments, though:

“If there are African ‘subpopulations’ (by which I believe you mean nations or tribes/ethnicities etc) that have a genetic mean IQ that is higher than the genetic mean of whites (or black Americans), then the American black-white gap can not be due to the ‘blackness’, genetically, since that subpopulation is also black.”

right. well, that brings us back to one of my “three laws of human biodiversity” and, not very coincidentally, the title of this post:

there’s more to human biodiversity than just racial differences.

the western (or maybe modern) world has a weird focus on the differences between races — at least among those of us who notice differences between people at all — both because racial differences are highly visible (especially physical differences — unless you’ve got your head stuck up your in the sand) and thanks to our unfortunate common history.

but — and i just had this convo with someone on twitter the other day — much of the variation between human populations is NOT found at the level of races, nor does it have anything to do with race.

WHY would it? such a scenario doesn’t make any sense from an evolutionary point of view: not a single one of the races has inhabited in its entirety only one environment or had an evolutionary history that was fully shared by all of its members, so obviously there must be quite a lot of intra-racial variation. and don’t forget, evolutionary histories include societal types (“every society selects for something”) and recent human evolution, so there really is absolutely no reason that all of the variation we see between populations should be found on a racial level.

we all know this to be true already: ashkenazi jews have the highest average iq of any population, and that group is not a race, it is an ethnic group. it’s northeast asians that have the next highest average iq, not all east asians (not indonesians, not filipinos). lactase persistence is found at different frequencies in white european populations, not equally across the wider racial population of which europeans are a part (i call them caucasians), let alone whites. protection against malaria isn’t evenly spread among subsaharan africans, either. and i have been blogging endlessly on possible (probable, imho) differences in innate altruistic behavioral traits between european populations. etc., etc. as jayman said in his most recent post: “Differences between human groups are fined-grained because evolution acts locally.”

who knows if some african subpopulations have higher genetic mean iqs than white or black americans (or other populations)? maybe. i look forward to researchers investigating the possibility. but i am in near complete agreement with chisala: the black-white iq gap is not due to blackness (or subsaharan african-ness), per se.

i say near complete agreement since i think that some of the variation in the average iqs of whites and blacks *might* quite possibly be due to evolutionary processes that affected very large populations (such as entire races+). MCPH1 haplogroup d, for instance, is known to be absent in subsaharan african groups. we have no idea if this gene (allele) is related to intelligence, but microcephalin is related to brain size, so it’s not implausible. i only bring it up to illustrate that some selection in human populations — including stuff related to our brains — has happened on the large scale — but as i said above, much of it also has not.

so it’s complicated.

but i do wish everyone would just ease off on focusing on racial differences all the time. the over-emphasis on race obscures an awful lot of fascinating (possible) biological variation between smaller sized populations, and the evolutionary processes themselves.

previously: hbd chick’s three laws of human biodiversity

(note: comments do not require an email. still not feeling well.)

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