[Moshe_Silnorin]

Raven's Progressive Matrices aren't really based on spacial rotation, but an interesting point. One thing we might look for to test this idea would be Raven's Matrices tests of illiterate Chinese farmers. They were developed in the late 30s, so it's possible such studies were done. Though we'd need to be wary of the Flynn effect.

We see similar IQ differences in Ashkenazi immigrants to America and Canada, and these differences have persisted over multiple generations. You would expect regression to the mean if it is purely a selection effect. Also, selection effects can't explain 27% of United States Nobel prize winners in the 20th century, 25% of Fields Medal winners, and 25% of ACM Turing Award winners, for obvious reasons. 10x overrepresentation isn't something selective immigration can explain when the the global Ashkenazi population is so small.

Wealth is tied with cognitive ability. Look at Jewish immigrants in the 1930s, most of them were extremely poor, but their children grew up to be disproportionately successful. Most people desire wealth. Intelligence is your ability to realize your desires. Intelligent people will tend to acquire more wealth than less intelligent people. As intelligence is highly heritable, this has class implications that can't be ignored.

[telotortium]

Regarding Progressive Matrices, you could try comparing Japanese and Chinese, who use kanji; Koreans, who use hangul, which is derived from kanji; and Vietnamese, who use the Latin alphabet (albeit with a lot of diacritics).