Over the past thirty years, most archaeological research in West Africa has focused on the record of human activities since 10,000 BP. Although the coverage is spotty and huge areas remain inadequately understood and documented, this research has transformed earlier notions of a West African past that was largely static until stimulus or intervention from the north transformed Iron Age societies. Furthermore, the sequences of change through time that this research documents indicate some unexpected and possibly unique historical trajectories.
Current evidence suggests that West African food production was indigenous and followed a different pattern from the familiar sequences of the temperate Old World (the Near East, Europe, and China) in which domesticated plants were an important element of the earliest food-producing economies. The earliest food-producing economies in West Africa were pastoral, based on cattle that were domesticated indigenously in northeast Africa, it appears, several millennia before the first domesticated plants appear in the archaeological record.
As archaeological research has shifted from a focus on isolated single sites, where data from one excavation were extrapolated and assumed to apply to a broad set of sites with nominally similar material culture, to the investigation of many sites within a region, our understanding of the complexity and diversity of the West African past has grown. In the temperate Old World, economic specialization, an early sign of growing social complexity, most frequently involved craft activities; in West Africa, an equally important aspect was subsistence specialization. By 4000 BP when the earliest documented domestic plants appeared, there was a concomitant development of specialized fishing economies that probably interacted with food-producing economies within the same region by means of subsistence exchange, creating a complex web of interdependent communities.
Upon the important bases of cattle (with varying percentages of sheep and goats), domestic cereals (millet, rice) from 4000 BP, and ecologically based subsistence exchange, complex societies emerged in favored locales in West Africa. These were areas of low rainfall (where the tsetse fly that carried sleeping sickness so frequently fatal to cattle and humans could not thrive) and abundant water.