Mexican crops push farming communities to Ontario and North Dakota

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.

Herodotus wrote down what Carthaginians told Greek listeners about a coast beyond the Straits of Gibraltar. The ships would land, the crews would set their wares out in a row along the shore and raise smoke. People living there came down when they saw it, left gold beside the goods and withdrew. The Carthaginians came ashore and looked. If the gold matched the value they took it and sailed; if it did not they went back aboard and waited while more was added. Neither side touched what the other had put down until the exchange was settled. The same silent barter appears in much later accounts of the gold trade in the West African interior. The metal most likely came from the alluvial fields of Galam and Bambuk on the upper Niger and Senegal. This is among the earliest written notices of West African gold reaching the outside world.

The El Convento site on the northern coast of Puerto Rico has produced the earliest radiocarbon assay for the Huecoid, one of the two ceramic traditions present at the opening of the Ceramic Age in the region. The date is a problem for the accepted model, which has these groups moving slowly from east to west along the island's north coast. At Maisabel the sequence points the same way. Huecoid ceramics were found in a sealed layer directly beneath deposits of the Hacienda Grande style, which is Saladoid. Sealed stratification is the strongest evidence archaeology offers, because a layer under an undisturbed layer is older and no argument changes that. Together the two sites suggest the Huecoid were established in parts of Puerto Rico earlier than at eastern sites such as La Hueca, where the tradition was first defined. Migration maps for the first pottery-making societies of the Caribbean are being redrawn around dates like these.

Horizon I on Martinique produced some of the earliest radiocarbon dates in the West Indies for the Cedrosan Saladoid, the pottery-making farming people who moved north into the islands from the South American mainland. Rouse treats the date as the opening of a long demographic change rather than a single landing. The islands were already occupied by Archaic-age bands, smaller groups who fished, gathered and hunted and who did not farm. Over the following centuries the farmers displaced them. Martinique sits in the middle of the Lesser Antilles, on the road running from the mouth of the Orinoco up the arc towards Puerto Rico and Hispaniola, and anything travelling that road passes it. I put a Martinique radiocarbon date on a Haitian timeline because the people the Spanish met on Hispaniola in 1492 came out of this movement. Their arrival is datable, gradual and about two thousand years long. Haiti has an indigenous beginning that predates every European in the story.