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From this article from The Guardian:

We instinctively assume that differences in behaviour that are in fact due to culture must be linked to – even caused by – characteristics of appearance. That is what the traditional notion of race is all about. But genetics has found no such innate origins of behavioural differences between “races” – and it is highly unlikely, given what we know about genetic variation, that it would. (my emphasis)

Because the term "race" is so poorly defined and because this categorization has been and still is an immensely important source of hate and discrimination, I will use the term "human populations" (despite the term being at least as vague). The fact that the term categorization into "races" does not make in any way a good representation of the partitioning of the genetic variance in human populations (e.g. see this post) is irrelevant to our discussion.

Are there any study who investigate the partitioning of genetic variance for a behavioural trait (e.g. drug dislike, aggressiveness, agreeableness, openness, reading performance, etc...) among "human populations" (defined one way or another)? Did they find a significant correlation? What is their correlation coefficient?


The article I refer to says

We instinctively assume that differences in behaviour that are in fact due to culture must be linked to – even caused by – characteristics of appearance.

In no way, do I expect that the phenotypic variation used to define races could "cause" much of an eventual genetic structure for a behavioural trait. I know it is a politically sensitive topic. Let's raise above it and discuss the evidence.

Estimating partitioning of genetic variance

If need be, see this post for a definition of heritability.

I realize that estimating the partitioning of genetic variance is a difficult endeavour and can easily be confounded with other sources of phenotypic variance such as the ones caused by social and educative systems. Any article that does its best to estimate a correlation coefficient between a behavioural trait and "races" is welcome.

Behaviour

Of course, the term "behaviour" is not perfectly defined. This has never prevented us from massively using this concept in biology and I don't think it should prevent us from using this vague categorization of phenotypes to answer the current question.

What behaviour am I interested in? ... pretty much anything that one might want to call behaviour. I am not particularly interested in behavioural differences that might be directly cause by a difference in the prevalence of a specific disease.

In the book IQ and the Wealth of Nations, Lynn and Vanhanen attempts measures of IQ among countries. These methodology has been highly criticized. I double that IQ could be considered as a behaviour but, while I would welcome anyone to include such work in an answer (along side its criticisms on their methodology; e.g. Witcherts et al., 2010; see also Rindermann 2007), I would rather like to focus on evidence that are not directly focused on IQ. I am fine with evidence that are on behavioural traits that somehow relate to our intuitive notion of intelligence (e.g. reading performance, spatial abilities, ...). This answer in the post Genes and Intelligence is very relevant and lists three articles that looks for loci that explain some variance in IQ.

Remi.b
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  • Obviously, this is a politically risky topic. It might be safer to approach it from a perspective on dog breeds. It should be possible to model evolutionary mechanisms that might cause genetic linkages between physical and behavioral phenotypes to emerge. – S. McGrew Dec 29 '19 at 13:53
  • Is there any evidence that (outside of a few pathologies) there is any genetic component to behavior? – jamesqf Dec 29 '19 at 18:10
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    My understanding was that variation within the so called races of humans was much larger than that among the "races". I'm also sure that I've read that there is more genetic diversity among "Africans" than among the rest of the worlds peoples. To me that suggests this question isn't actually scientifically based since it presupposes that the culturally based (i.e "made up") category of race has a genetic basis. See for example this Scientific American article. – tyersome Dec 29 '19 at 20:09
  • @jamesqf Thanks for your comment. I tried to address it by extending the long follow-up to my question. Let me know if you think my question is unclear. – Remi.b Dec 29 '19 at 22:33
  • @tyersome Thanks for your comment. To me that suggests this question isn't actually scientifically based since it presupposes that the culturally based (i.e "made up") category of race has a genetic basis. I think we can all agree that there is some genetic structure for skin color and hair straightness among Nigerians and Japanese. I do not want to state that such phenotypic variation have been more important that cultural differences in defining races but the existence of some non-zero (yet eventually very small) genetic structure exists. – Remi.b Dec 29 '19 at 22:41
  • @tyersome I do not state either that races are in any way a fair partitioning of the existing genetic structure in humans (I have now added a link to a post that discuss the impressive genetic diversity among modern day Africans compared to the rest of the world). I am asking whether any such structure has been investigated for a behavioural trait. If you still think my question isn't scientifically based, please let me know why and how I can improve it. Thank you – Remi.b Dec 29 '19 at 22:41
  • I guess the problem I have with this is that "race" is known to not be a valid categorization. Consequently it seems to me that any question based on "race" is inherently problematic. There are genetic factors that control traits like skin color and hair curliness, but there are also genetic factors that control ear lobe attachment — you could define ear-races based on that, but it also wouldn't be meaningful. It isn't clear to me how to fix this problem — maybe you could substitute "human populations" for "races in humans"? – tyersome Jan 03 '20 at 00:36
  • @tyersome I rewrote the post using the term "human population" instead of "race". It allowed me also to shorten the post as I don't have to clarify that I understand how meaningless the concept of race is in explaining the partitioning of genetic variance among humans. Thanks – Remi.b Jan 03 '20 at 13:46

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