One thing I think is important to remember is that 90% of what Europeans could not build a city either. Most of what we have exist because we built a system that magnifies the efforts of the smartest 10% of our population and allows them to thrive and we record their knowledge and we pass it on to others who can utilize it. So if tomorrow somebody put you out in the woods 90% of you could not build a log cabin. Even if you didn't know plans or anything you certainly couldn't figure it out. You couldn't create cement from wood ash. Lots of things that 90% of people can't do. So the real difference I think in European populations is number one that the average IQ is higher so the top 10% is magnified and an exponential level if you look at a bell curve. That's the way it works. When the average of the whole population moves up the fringes are actually magnified much more than the shift in the average population. So number one you get a huge increase in the number of people with a higher iq. And number two the European civilizations have always had a way whether it's libraries or Masonic guilds and other things where knowledge that was known by some people was passed down to others so they could build on the knowledge of their forefathers. African people's never had such a system. As far as I know they never built me libraries or anything like that. They may have passed some knowledge down verbally but it certainly wasn't extensive if they did.