I could simplify this argument.
Culture and social conditions, over time, influence natural selection.
Jews are an excellent example of this in several ways. For example, culturally Jews admire education, and they have a rare cultural acceptance of “good ideas”, no matter *who* thinks them up. Even if their hated enemy has a good idea, they may just adopt it for their own use.
Over many generations this has led to intellectualism being an admired trait, resulting in reproductive preference.
But importantly, while on the surface the flip side of this represents some diminution of physical traits, these are still kept in reserve, so that, for example, in just a generation or two, Jews can become very strong athletes.
But only if they have a cultural impulse to do so.
It should be noted that the Jewish cultural (or possibly cultural/genetic) predisposition for intellectual activities was not a tremendously positive aspect for success in life for most of history.
It’s only in the last 100 years that the classic geek/nerd became someone likely to become wildly successful. (More accurately, the last 50.) For example, had Bill Gates been born 200 years ago, would he have become one of the richest men in the world?
Not likely. The traits necessary for success change over time.
So the traits Jews had developed in isolation (imposed by others) and which may have helped them survive, allowed them to thrive explosively when the world changed and those very traits became in great demand.
Yes. So, what admired trait results in reproduction among the various races?
In Europe, during the Middle Ages, Jews were, to a large extent, excluded from owning land or being farmers. They made their livings mostly from trading, moneylending, and skilled crafts -- trades where stupid people are at a big disadvantage. The smart ones were able to keep their families fed, the stupid ones died out. Evolution in action.