Istwa Nou

The link between inventing agriculture and spreading a language family holds well outside Africa. Andrew Pawley argues that the people who worked out cultivation in interior New Guinea in the eighth and seventh millennia BCE spoke proto-Trans-New Guinea, and that from around 7000 BCE their descendants carried both the crops and the language across much of the island and into neighbouring island chains. Recent work points the same way for the northern and northwestern edges of the Fertile Crescent, where speakers of languages related to the North Caucasian family had a major hand in creating farming in the tenth and ninth millennia BCE. People of that background probably also carried the first agriculture west across southern Europe and on into the interior and the far west over the seventh and early sixth millennia. The pattern is a global regularity. Africa's three independent agricultural traditions and their three language family expansions are the continent taking a full part in it.

Farmers displacing foragers is only part of the story of early Holocene population movement. The climate shifts that opened the epoch also opened new ways of taking wild food, in greater quantity and greater variety than before. The first wide distribution of Nilo-Saharan speakers is the clearest African case, and it ran on an elaborated aquatic foraging economy: fishing and hippopotamus hunting along the waterways of the green Sahara, west from the Nile to Lake Mega-Chad and beyond. Nobody involved was sowing anything. The usual account of the Neolithic treats the change from foraging to farming as a clean break, with foraging on the primitive side of the line and farming on the civilised side. The record does not sort that neatly. Some of the largest demographic transformations of the period were powered by people who simply got much better at harvesting what was already there. Human ingenuity under environmental pressure takes more than one form.