let's take civilization off the table for now.
I'm under the impression that controlled studies have found race-intelligence links. (maybe this is my confusion of basic facts). Seems plausible.
Sociology is pretty strongly corellated with this race thing, and race is more visible. Violence is definately linked to race in the USA (even if it's only through social class, but I've seen arguments that race is an even better predictor).
It would be nice to have some solid literature surveys on this. Unfortunately, given the controversy, it's hard to just trust what the academics are saying.
If it's linked "through social class", it's not linked directly, which is what's under discussion. No-one is claiming that race has no effect on class and/or class has no effect on the traits under discussion. You are claiming that low intelligence and violent tendencies are racial characteristics, which is generally considered racist nonsense by, well, non-racists.
Here's the new thread for posting quotes, with the usual rules: