Istwa Nou

Farming reached the far north and the far south late, because the environments there resisted it. That delay changed the outcome. Immigrant farmers were turned aside from country their crops could not handle, which left the people already living there time to work out which parts of food production suited them and to fold those parts into economies that had been entirely foraging. The Uralic speakers of the European boreal forest and the Khoe peoples of southern Africa are the clearest cases. Two processes are running here. In one, farming populations carrying a complete package move in and absorb or displace the foragers ahead of them, which is the Bantu pattern. In the other, foragers stay where they are and take on livestock or a crop while keeping the base of their old economy. The margins of the agricultural world are where the second process had room to happen, and it produced mixed subsistence systems that belong to neither category.

By the later first millennium BCE a set of crops from Mexico had been added to the Eastern Agricultural Complex of what is now the east central and southern United States, and farm output rose sharply. Population followed, and then territory. Ancestral Iroquois-Cherokee speakers expanded across country reaching from present day Tennessee and North Carolina up to southern Ontario. Early speakers of Caddoan and Siouan languages carried the same economy north through the Great Plains as far as modern North Dakota. In South America and the Caribbean, the very wide distribution of the Arawakan and Tupi-Guarani language families may have a similar history behind it, which bears directly on the islands, since Arawakan speakers are the people who settled the Antilles. The mechanism repeats on every continent. Crops move between independent centres of invention, food supply improves, population grows, communities expand, and a language family ends up spread across a subcontinent. Maize, beans and squash did in North America what yams and sorghum did in central Africa.