Africa was one of the sites where agriculture began. archaeological investigations suggest that knowledge of cultivation moved west from ancient judaea (southern palestine) and arrived in the nile delta in egypt about the fifth millennium before christ. settled agriculture then traveled down the nile valley and moved west across the southern edge of the sahara to the central and western sudan. by the first century b. c., settled agriculture existed in west africa. from there it spread to the equatorial forests. african farmers learned to domesticate plants, including millet, sorghum, and yams. cereal-growing people probably taught forest people to plant regular fields. gradually african farmers also learned to clear land by burning. they evolved a sedentary way of life--living in villages, clearing fields, relying on root drops, and fishing.

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