You could ask similar questions:
Why are so many World Champions of Jewish descent?
Why are so many grandmasters Russian?
The answer is probably the same: a culture where chess fits the values.
What about women? There is also the sensitive issue of IQ differences between the races. I think the question being asked is unimportant. The answer is a mixture of nature vs. nurture.
Women in chess is also a cultural thing. Lazlo Polgar somewhat proved that this is not innate.
IQ tests are also liked to culture. There exist alternative IQ tests where black people from Africa score better than caucasian people.
Disagree that it's purely cultural. The races evolved separately, so it makes sense there might be variation in stature and IQ. Women are worse at chess due to an on average lower spatial intelligence. The structures of the brains for men and women are just different. Men have bigger brains but women have more gray matter to compensate. Sorry if these facts are too much for you. This topic sucks.
Do not tell me Jews or Russians (not a race) evolved in a favourable way. Judith Polgar and here sisters proved that women can get to the top 10 chess players in the world, despite so much less women playing chess.
The brain is malleable. Evolution can however explain why black people excell in physical sports, like athletism, soccer...
Jews have higher IQs because the Nazis spared the intelligent ones in order to utilize them for their research. So, Jews are on average more intelligent because of the genes that were passed down from the survivors. Polgar is just one woman out of 1500 GMs. I already proved my point on that one. As far as the Russians, id agree with you that it's mainly cultural, as they take a more methodical disciplined approach to studying chess.
How does evolution explain physical changes but not psychological changes? That's absurd. Stop with the politically correct answers already.
So you're racist?
@SonoftheSun1 How's that racist? Those are facts. It's called science.
www.youtube.com/watch?v=5r_E0bXF54U&t=13s