Results in both directions are published all the time.

[2] above already shows there is no scientific basis to genetics explaining intelligence variations in human groups. Other studies [3] back this up, and there are studies clearly tying intelligence variations between human groups to environmental factors [4] [5].

Based on the easily googled wide availability of this information and given the environmental causes of IQ differences, I wonder if an easy scientific corollary is that racists must have environmental factors behind their inability to comprehend the established science in this matter. LoL

[3] https://doi.org/10.1073/pnas.2322874121

[4] https://doi.org/10.1037/a0026699

[5] https://doi.org/10.1037/a0029772

> If it’s consensus, it isn’t science. If it's science, it isn't consensus. Period.” - Michael Chrichton*

*not a scientist

What do you mean "it replicates worldwide"? What replication are you referring to?

The US racial groups are US specific. The bundling of different ethnicities into a race (like grouping high pigmented out of Africa with Africans instead of with low pigmented out of Africa) is silly.

Do those groups relate closely to what people generally mean by race? Race as defined in which culture? I know from personal experience that its not the same definitions across cultures. How big are those differences compared to differences within racial groups?

> What if some of the observed racial differences were caused by a lack of vitimin D, due to darker skin photosynthesising less of it? Vitamin D is essential for brain development. Black people in northern climates get less of it than evolution intended. This lack of vitamin D might be causing reduced brain development in black populations. If that is true, we could fix the prison crisis and racial IQ differences with a pill!

Well, that would be knowable from a study of Vitamin D levels in the incarcerated population vs non-incarcerated among those with the same skin tones. I don't see any reason to bring IQ into this, nor race (vitamin D absorption is tied to skin tone, so a dark skinned person of Indian descent is as likely to have vitamin D deficiency as one of sub-Saharan African descent).

> If we block all research into a problem then we can’t solve it.

Establishing or refuting IQ differences among "races" is simply not a problem. It is sought after, at best, as a scapegoat, to deny any responsibility of racism in the measurably worse outcomes of people with certain heritage than others. Refuting race-IQ genetic correlation would simply eliminate this scapegpat, that most scientists don't actually believe in; while confirming it would just mean the problem is hopeless and nothing can be done to improve the situation.

It's a good tool if you want to rank people, it's a bad tool if you want to help people. IQ tests couldn't (and can't) even detect dyslexia, a specific disability which you can get help with, which was known even in Terman's time. IQ tests by design throw out all information which could complicate ranking people. If your goal is to help, why would you measure people with a tool which can't tell the difference between dyslexia and concussion?

IQ tests have been revised several times to address things like that, like that they "unfairly" penalize dyslexia, or that they had lots of questions which were easier for people of specific social backgrounds. Every time they were, they naturally became less "predictive", since both dyslexia and not belonging to the California white upper middle class give you pretty obvious disadvantages in life outcomes.

So don't waste time on IQ, and don't waste time on other academic culture war BS either.

> correlated to

Correlation measures whether Y=mX+c holds with small error. I sometimes think that many people unknowingly assume that all dependencies are somehow straight-line ones. This is distinct however from "linear approximations" in physics, which can at least be justified sometimes.

I also suspect that correlations of 0.5 or lower are often just statistical noise.

The US never truly abolished slavery, it turned it into a punishment, and started sending black people into prison en masse. There is no prison crisis, in fact the prison industry is flourishing like never before!

All of the studies I have ever seen discussed are hopelessly terrible. People like Murray cite apartheid-era South Africa IQ studies, for example, where some of the black children being tested didn't even speak the test language natively. Others look at country differences and claim to extract racial differences from that, as if education and culture play no role in IQ scores. Virtually none of these studies actually look at the genetics of the populations they are testing, they just go by outward aspect, thus making most of their genetic claims laughable. And, of course, many of them are either small samples, p-hacking, or outright fabricated - like many papers in psychology.

That doesn't matter.

In the ideal world, assuming this is true, we could then ask for the question of, well, what can we do about these people with different intelligence levels?

Intelligence is not just a single thing. We can assign a number by an intelligence test, of course, but there are lots of ways to look at it that are more nuanced. Generally, you're not going to say someone is better than everything you're going to find that someone is better at some things. And so can we direct people to the things you're better at for the better of everyone? Division of labor is a good thing.

But contrast, assuming that we find it's not true, then we can ask, well, why are we finding these differences in the data? if it's not genetic and perhaps we can find what it really is and then improve those groups that are currently disadvantaged.

The larger point is you have to know before you can make a useful adjustment.

We know that people with red hair tend to metabolize anesthesia differently. It is not completely implausible that there is also a correlation between looks and other traits, although it seems almost impossible to me to untangle cultural, environmental and genetic effects.

Skin colour almost certainly doesn't affect intelligence (much). There are plenty of dark skinned upper caste Indians who are intelligent, for example.

We can predict skin colour reasonably well on the basis of very few genes. We need many more to predict intelligence (and we can't predict it nearly as well).

On the other hand, however...

...there are a lot of people who happen to have whatever genes cause dark skin who also happen to have lot of other genes that do other things...

Some of those others things include a genetic protection against malaria. Others confer a genetic protection against a nasty parasitic worm that prefers to live in the kidneys. The downside is that that protection itself is a bit unhealthy for the kidneys.

And some of them do a might good job of seeming like they cause lower intelligence. If we use our genetic prediction models, then they do in fact predict a lower intelligence.

"Skin color"? There's never been anybody with functional intelligence who thinks that skin color alone determines race.

That could also be explained by cultural differences, I don't think the evidence is overwhelming.

Or it could be discrimination. There are studies that show that black and white mixed races children did not score any higher than children with two black parents, while white people score higher than black people on average, which may point to some discrimination impacting IQ.

There are significant cultural and economic differences between those communities. These will be similar between Singapore and Malaysia. The Chinese and Indians are sufficiently recent immigrants for their culture to still have a lot in common (they speak the same language, follow the same religions, have inherited attitudes) with the places their ancestors came from.

No, you mean to say "if we define intelligence as the output of IQ testing", which clarifies that you're projecting from statistical surveys (with all sorts of potential confounders) rather than some directly queryable and innate attribute of people.

Race was only ever a stand in before we had an accurate understanding of genetics.

[dead]

Now I want to say that your ideas don't come from your brain. But of course they do, as a result of interaction with other people's ideas, some of which were written down. (Don't worry, I'm not a dualist.)

The thing is that no matter how fancy your bicycle, I can still ride my shitty bicycle to a university, and you can ride your lubricated carbon fiber bicycle into a ditch, and then you're not so smart. If what you call intelligence is how fast your bicycle typically goes into the ditch, then sure, it can be measured on a scale and you have more of it.

Sure, if the rock has good ideas.

(Rocks don't have ideas.)

A lot of HN is currently about rocks that we've made very smart, in case you haven't noticed. I don't want archeology polluted by generic academic culture war stuff, so can we please leave "intelligence" out of it?

Haplogroups aside, the replacement over thousands of years is the most interesting detail to me.

In Iberia, you have northern Iberian groups which maybe spoke a bit of an Indo-European language at first, and they are invading Southern Iberians and leaving almost no trace of other haplogroups.

Britain is less interesting because basically it was a regular colonization/invasion of the kind we know by Britons; although there is a genetic trace left of the megalithic people, they were swamped.

As a contrast to the Iberian case, we have several steppe invasions in the historical record but most of them look nothing like it.

The Khans did expand rapidly and engage in some wild oat seeding but there is barely any evidence that they ever were in most of the places they conquered. The Huns were basically new management for Germanic tribes. Again, no trace of their existence.

The only one that looks a bit like the Indo-European expansion is the Turkish invasion of Anatolia where by the end you have a bunch of South-Eastern Europeans with minor Asiatic ancestry effectively larping as Islamic Asians and even becoming the center of the Islamic world for centuries.

But, even in the Turks, you don't see full Y-DNA replacement, not even with the power of Islam.