A nun, some woman (women are far more aware than men on emotions as their hormones basically grant an A+ on social skills) stated that Black People weren't dumb, but African people had no tradition at all on stimulating or paying good attention babies/toddlers as the Western mom do with little plays and the like. That lead to mild development issues. She followed some children with more Western-like educations and caring and they got far better marks than the ones locked to their cultures.
Add a far better nutrition on top and now you know the reasons on why the Black African countries are underdeveloped. Westernize them and their IQ will boost like crazy.