But I bet there will be a ton more of that too, thanks to the high quality dataset.
Interesting. I find that part of the paper the most exciting. We always knew selection would happen for valuable traits. But seeing demonstrations of it in the timelines we have is pretty important.
This study covers about 10,000 years of recent human evolution in Europe and West Asia.
From the abstract:
>in the past ten millennia, we find that many hundreds of alleles have been affected by strong directional selection. We also document one-standard-deviation changes on the scale of modern variation in combinations of alleles that today predict complex traits. This includes decreases in predicted body fat and schizophrenia, and increases in measures of cognitive performance. These effects were measured in industrialized societies, and it remains unclear how these relate to phenotypes that were adaptive in the past. We estimate selection coefficients at 9.7 million variants, enabling study of how Darwinian forces couple to allelic effects and shape the genetic architecture of complex traits.
- lactose tolerance
- immunity and disease resistance
- lighter skin at northern latitudes
- metabolism and vitamin D processing changes in response to changes in diet after the rise of agriculture
All these traits go beyond just increasing the odds of survival, they improve the life of the individual directly. I.e. they confer fitness. Individuals carrying those traits will, on average, in that ecosystem they are inhabiting, be more healthy than those who don't.It's like holding a large ball in place on a hill that sees frequent tremors. If the ball is still halfway up the hill it's being held in place, if it's being held in place it's still halfway up the hill. It might be considered a tautology if you're only working with symbols and ignore all the mechanistics.
Different evolutionary paths between races/regions, with impact on mental health and cognitive performance.
What you think the implications are of that for your present day lived experience, that might be a different conversation.
But that's a strawman. Racism is wrong, even if there are minor genetic variances across populations (which... seems obvious?) Variance within a population strongly dominates the weak cross-population effects, and personal history (nutrition, education, etc) strongly dominates that.
And that's setting aside the moral implications of judging someone or changing your behavior towards them even if you have somehow measured them to be "less intelligent," as if that was a single axis of worth.
Because, apparently, this needs to be said.
That may certainly be true.
(Not OP, but) I always shutter when we want to deny scientific results because it might be "helpful" for someone making a racist argument.
My personal belief is that truth is the goal of science. Even in cases where the truth is uncomfortable.
There is no scientific breakthrough that has occurred sans politics. Politics choose the winners and the losers, and the realm is science is no exception.
All science is political, because the scientific institutions are made up of people, who are political. Your research project lives and dies by politics, as does your dissertation, who gets published, who receives awards, etc.
So when it comes to research of limited utility that has a nasty cadre waiting in the wings to pounce upon it, the wise person would think twice.
There is no political agreement on whether having or not having affirmative action programs is racist (or against which racial groups).
Affirmative action might be problematic for totally unrelated reasons. Maybe there's no way to do it without being racist towards Asians, or without selecting a tiny privileged cohort of Black families to accrue benefits on (simply "applying for college" in the first place situates most people in a position of privilege).
We absolutely do not know enough about the psychometric science here --- forget race entirely and just try to pick through theories of intelligence and its mutability --- to make public policy decisions. It is, at present, a pure scientific concern.
Contra claims elsewhere on this thread, science on this topic isn't suppressed at all. There are multiple branches (in quantitative psychology and genetics) that study this issue actively, and if you follow it, new papers aren't rare. But directionally those papers aren't confirming the priors of the people claiming the science is suppressed, so they don't get acknowledged.
My main resistance to that is much the same as yours: the differences are so small, that re-architecting society around them is not going to be enough juice for the squeeze.
But one could also argue that the juice is not even the point: by re-architecting society in this way, you "pre-brutalize" your population so that their threshold for violence against "others" is lowered. Thus your population is closer to being wholly militarized, and theoretically is more effective in war, and is less captured by "weak" or "unmanly" moral ideals, such as empathy.
While this might seem a virtue to someone of an expansionist mindset, in application this principle never, ever works well - again, thanks to those tiny differences. If a citizen is pre-brutalized to have a lowered resistance to killing those with curly hair, how long is it before they kill their next door neighbor with wavy hair, over something like lawn furniture?
Pre-brutalizing your populace to killing any sapiens is enough to brutalize them towards harming anyone else. This is the core of the "imperial boomerang", or the colonial boomerang theory, as to why the great wars of the 20th century took on such a nasty character. The ease with which we dehumanized subject populations was - all too easily - redirected against the neighbors, most memorably with Germany trying to re-create the American West to their East.
If you’re talking about trying to improve the genetics of populations at scale… yikes.
> We finally observed signals of selection for combinations of alleles that today are associated with three correlated behavioural traits: scores on intelligence tests (increasing γ = 0.74 ± 0.12), household income (increasing γ = 1.12 ± 0.12) and years of schooling (increasing γ = 0.63 ± 0.13). These signals are all highly polygenic, and we have to drop 449–1,056 loci for the signals to become non-significant (Extended Data Fig. 10). The signals are largely driven by selection before approximately 2,000 years )*, after which γ tends towards zero
Presumably pressure in different regions lead to different combinations of those alleles, which I think they are shorthanding a bit, but the fact that those alleles exist makes blank slate theory a kind of rough assumption
So really when you say select for household income among western populations, it might be hard to actually find any real signal that is actually causal that isn't due to simple demographic and historical reasons, due to the lack of power you have in sampling rare demographics within a given category such as high income.
If anything they seem to support homogenization of intellectual capacity/mental health in Eurasia since 2kya.
The methodology, if it holds up, seems to hold a lot of promise for answering questions like this in the future.
Now I would be quite curious to know how they constructed this polygenic score