I think it's fair to say that at birth, any person around the world has the same capacity for 'intelligence' as any other person.
That's definitely not true. Many people are born with diminished intellectual potential. Some of them are born with genetic disorders that render them unable to ever fully function as adults. I think you meant "healthy" people, but I think again that you're over simplifying the situation. I was raised in the same environment as my sisters, and I can tell you for certain that we don't have the same intellectual aptitudes. It's not even really particularly close. That's because we have significantly different genetic combinations of my parents, and they had very different genes to contribute, some of which were never received by each of their offspring.
People are genetically different, and that includes intellectual aptitudes and predispositions. I don't think there's any evidence to suggest that all healthy people have the same capacity
overall for
intelligence. But I don't think there's any evidence to suggest that that's not the case either. That's because I don't believe we can reliably estimate
overall intelligence, or even figure out what that means. So the conclusion that it's evenly distributed is unfounded (and unnecessary).
We don't.....
We simply acknowledge that there are so many differences in other variables that it is likely there is likely a difference in intelligence too. Or we choose to ignore it, as most other posters are doing,
No. That's not how it works. We know there are genetic differences among people of different "races", in fact, we know there are genetic differences between all individuals. You don't need to keep supporting the notion that people are physiologically different, they are. All of them. There are differences in blood types, predisposition to various diseases (some of which are genetic), height, bone density, muscle mass, etc. etc. among
all individuals (ok, maybe not for identical twins). Every single person has a different genetic propensity for these traits. It's true that some traits go together, you might be able to generalize a set of "racial" characteristics for certain genetic physiological predispositions.
The problem is you seem to keep wanting to generalize that to intelligence, and that's basically impossible to do. We can't even measure what you're talking about, so proving a difference is not going to be forthcoming. I can tell you for sure that there are certain genetic traits that are exactly even handed among the races. You're not any more likely to have a 3rd eye, be missing a 2nd eye, have 3 arms, two hearts, two brains, etc. etc.
So there is no reason to suspect that everything is different just because some things are often different in various fairly arbitrary bins that you group people in.