China has been using exam scores to select its civil service elite for close to two thousand years, web search “civil service, ancient China” for details. Assuming a generation is 20 years, two thousand years represents 100 generations.
Those individuals with high scores and thus government jobs had stable incomes and better living conditions, in general, than those with lower scores. Their children were more likely to survive, and thus reproduce.
How much does a hundred generations of such winnowing help evolution improve test-taking ability in a population? I’m no geneticist but I’d guess, quite a lot.
Meanwhile in Europe during the same period the Roman Catholic priesthood was siphoning off smart boys who, as priests, were at least supposed to be celibate, even if they didn’t always abstain. This too had evolutionary implications, albeit in the opposite direction to that in China.
Following the rise of Protestantism and the Reformation in the 1500s at least some of Europe had married clergy. Meanwhile it's likely celibacy was even more closely observed in the Catholic areas.
Now many generations later we see that Asian kids have higher average test scores than those of European descent. Should we be surprised? Not even a little.
Test taking ability, aka IQ, varies among individuals and China has been eugenically breeding for high levels of this ability for well-nigh 100 generations. Meanwhile in Europe many of those with this same ability had their breeding at least restricted.
You don’t need a high IQ to see what the outcome of these two policies should be, and in fact is.
