noun, Pathology. 1. the accumulation of excessive ketones in the body, as in diabetic acidosis. Origin of ketosis. 1915-1920.
Climate zones of Africa, showing the ecological break between the hot desert climate of the Sahara Desert (red), the hot semi-arid climate of the Sahel (orange) and the tropical climate of Central and Western Africa (blue).
And perhaps some people in western Sahara retreated southward to a wetter climate, taking with them their pigs, sheep, goats, cattle and knowledge of farming. In the Ethiopian highlands, herding and farming appeared, people there growing a cereal crop called tef and starchy stalks called enset.