>>12484911It almost completely depends on population density.
The khoisan (who are primitive by African standards as well, BTW) have no reason to build a skyscraper. There is nowhere near enough of them to fill and use one. They don't need a computer either. They don't even beed a shopkeeper, because what for? There is few enough of them to agree who gets what and too few for anyone to specialize and divide labor. They can pick the food they need and they have pretty much no reason to spend any more effort on anything else either.
Advancement is all about density. You can't have a spearmaker until you have hundreds of hunters to serve. For a baker, maybe at least thousands. There are surely professions that are only worth it in millions. And it really is, you can see even ants with their tiny brains often engage in agriculture, "animal" husbandry, care for and bury their dead, build complex nests, etc. But only those who live in large numbers do. Those who live in smaller groups just wander the land like those people do and never build anything much. (There are those that live in trillions sized colonies, but that is a recent thing, possibly triggered by human activity, and they indeed may be limited by their intelligence, which is however vastly lower than even our close animal relatives)
Same is with research. It becomes massively cheaper per capita once you have more inhabitants. A research that takes ten millions man hours in total needs those two million man hours whether you are a khoisan with his tribe, or a billion sized empire. You can check the growth of a country lags behind its population growth, but then it stops. The fastest growing countries physically are the fastest growing economically, always.
