undefined | Better HN

0 pointskloop2mo ago0 comments

I think they're talking about this bit:

> 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

0 comments

5 comments · 2 top-level

svnt2mo ago· 3 in thread

I haven’t had time to really dig in to the paper but these data (from only one region) are limited in their ability to compare regions, right?

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.

kloopOP2mo ago

No, this paper doesn't seem to talk about regional differences. The implication seems to be that it wouldn't be surprising to find differences between groups that separated more than 2kya, as there was active changes going on before that time. Not that it predicts any specific differences

> If anything they seem to support homogenization of intellectual capacity/mental health in Eurasia since 2kya.

I would be interested in how you came to that conclusion, unless I'm misleading your post and you specifically mean West Eurasia

svnt2mo ago

I meant West Eurasia, I agree it doesn’t seem to support any broader conclusion.

ano-ther2mo ago

Yes, they only had data for West Eurasia.

> Just because an allele, SNP, or trait swept into or out of West Eurasia during this time doesn’t mean this happened only in West Eurasia. Researchers can use the new computational methods to look for directional selection in other populations worldwide that have enough ancient DNA sequences and construct a clearer picture of what’s unique to different groups and what generalizes across populations.

> Reich expects that future studies will show that shared selective pressures acted on some of the same core traits across diverse human groups, even as those groups split off and migrated to different parts of the world over tens of thousands of years.

https://hms.harvard.edu/news/massive-ancient-dna-study-revea...

asdff2mo ago

It is important to consider that these alleles are merely correlated to behavior and are not proved to be causal of any behavior. For example, maybe you sample bankers in NYC. You can probably assume you'd get a lot of perhaps semitic genetic background in this dataset. Now, would you conclude that Jewish people have some inherent gene that makes them want to be bankers like a moth to a lamp? Maybe you would. But more likely situation is that people tend to follow the profession of people in their lives who work that profession and can inform them about it, and for centuries there were real legal restrictions in a lot of places preventing anyone but jews from being allowed to charge interest. So, pretty good odds today as a jew you know someone who works in finance and can help at least to some degree point you towards that field.

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.

j / k navigate · click thread line to collapse