re: Why Is Africa Continent Still Full Of “Developing Countries “?

Relying on IQ in historical discussions isn't a reliable metric. Firstly, nutrition levels seemingly declined after the neolithic revolution, where groups of people decreased in height and weight. Nutrition levels determine quite a bit of IQ, up to one standard deviation. One meta-study of 37000 Chinese children showed an IQ difference of 15 points based on the addition of iodine alone, which is a massive swing. Given the inconsistent levels of nutrition in the ancient world, our notion of IQ isn't necessarily applicable to those civilizations. Secondly, African civilizations on river valleys in East Africa were as highly developed as European ones until antiquity. Things like centralization efforts, trade routes, and availability of domesticated plants and animals are much more predicative of the success of ancient civilizations than something as nebulous as "intelligence."