>>96089289You really think biological variance stops once it reaches the brain?
Let’s take the politics out of it and go back to the basics of biology.
Take two populations of the same species. Not humans- let’s say rabbits.
Isolate them genetically for a significant period (usually such isolation is caused by geography but it doesn’t matter why so long as interbreeding is minimal and is over enough generations for natural selection and genetic drift to occur).
Will there be a divergence of traits between the two populations?
The answer is yes, of course. Some traits will diverge becasue of natural selection, some because of sexual selection and some just becasue of genetic drift.
After all that is how evolution works - it simply must be the case.
Evolution isn’t just about when two populations diverge so greatly that a new species or sub-species forms - it’ happening daily for all sorts of traits and characteristics of an animal.
And the traits that most directly impact on fitness will tend to be subject to strong selection.
So wind it back to humans.
Have certain populations of humans being genetically isolated from each other for many generations?
Yes. We tend to call them ethnicities.
Will their traits vary as between population groups?
Yes. Hair type, blood group, eye colour, facial features, ability to digest certain foods, average height, body shape etc. All these traits demonstrably differ between ethnic groups.
Is intelligence a trait of humans that will likewise vary?
You can logically only choose one answer:
A) Yes - and as intelligence is one of a human’s key traits it is likely to be selected for quite strongly in different environments and communities,
B) No - intelligence is a special trait - alone amongst all traits it’s not possible for it to vary between groups at all - all groups of human beings have the same average intelligence.
If you pick B fine, but don’t expect to pass a biology class any time soon.