Indeed, it might. Typically for breeding of animals, it’s seen as advantageous if one wants to propagate a singular trait, to breed that animal with one of its grandchildren. Direct breeding from an animal to one of its children isn’t typically seen as that great of an idea. Since it seems to dredge up what are seen as negative traits and is in that regard, rather unpredictable.
Curiously, one of the best proven ways to improve an isolated breed, is to bring in an animal from a breed that is a bit removed from it. Such as the Arabian horses into speed horses of Europe and the Shires and Clydesdales into the horses in America.
IQ tests are nuts. They’re essentially based on one’s vocabulary, knowledge of mathematics and some logical questions, all being graded on correct/incorrect and time of completion. So, if someone has a lower base knowledge, they will score lower. If someone has a reading disorder, such as dyslexia, they will score lower.
Regarding Trump, his vocabulary, as used in interviews and non-scripted speeches is poor. From interviews with the bankers who attended a meeting regarding the restructuring of his casino’s, they said that when they got to speaking about numbers, it was as if Trump had never taken “Business 101”. And to his logic, well. . .
But yes, learned ability and natural capacities are two very different things.
For African Americans, studies have shown that up until the 1st to 2nd grades and just beyond, they are equal to everyone else in America. But after that, due to social economic issues and horrifically underfunded schools, their performances fall off in comparison, on average, to those who are more privileged.