> These aren't "races" per se but they are a valid and interesting taxonomy of people.
The thing about groupings like this is that they only exist in the statistics.
If you take two populations of otherwise identical people and then isolate them from each other, they'll diverge over time. Maybe the land is different, or the weather, and some genes are better adapted to one place or the other so they become more common there.
That's just averages. Originally 50% of the combined population had trait A. Over time, it becomes the case that 30% of the first population has it and 60% of the second population. You can measure the difference in the average. But the people in the first population who have the trait are the same as the people in the second population who have the trait. It just happens to be the case that that trait is better adapted to the place where the second population lives. If you want to talk about something, talk about people who have the trait or don't, rather than where their ancestors lived.
> When we're talking about IQ, asking "why is does it differ across identifiable groups of people?" seems to be a very controversial question to ask or attempt to answer, often getting you lumped in with the Nazis, which was my original point.
Oh, absolutely. And if that's true, it's true whether you want to hear it or not.
The salient point is that the Nazis are still wrong even if it is. Because it's all still just averages. If there is some gene that makes you smarter and 55% of "white people" have it and 45% of "black people" have it and as a result the averages are different, the conclusion obviously isn't that all white people are smarter than all black people, so Nazis are still wrong.
There is also no concrete proof that that's the case rather than the disparity being a result of nurture rather than nature. It's legitimately hard to separate them out even when it's not as politically charged as this.