The Prehistory of East Africa*

PREHISTORIC cultures in East Africa are dated mainly by typological, faunal, and climatic correlations with other areas, chiefly Europe. This relative dating is precarious and unsatisfactory. Very few absolute dates have been established in Africa as a whole (apart from Egypt in dynastic times); except for three dates obtained from varved sediments in the Kenya rift valley, there are no absolute dates in East Africa upon which to build a chronological framework. Radiocarbon dates for industries in the Anglo-Egyptian Sudan, Northern Rhodesia and northeastern Angola do, however, tie up to a certain extent with industries in Kenya, Uganda, and Tanganyika. The climatic sequence built up by Wayland in Uganda, and Leakey and Nilsson in Kenya, is well established and has been applied over most of Africa, though the number of pluvial periods, and particularly the numbers of subdivisions within each period, may not be the same in all parts of the continent. Evidence of Quaternary climatic episodes is obtained mainly from the following sources: high lake and river terraces; former greater extension of glaciers on mountains; the nature of fossil soils, wind-blown sands, chemical alterations, etc.; raised sea beaches; and faunal evidence. Relative dating is then achieved by the problematical correlation of climatic events in low latitudes with those of high latitudes. The Kageran pluvial of Villafranchian times is the first period of increased rainfall recognized, after the prolonged aridity of the Pliocene, in Uganda and western Kenya (it has not been recognized in the Kenya rift valley, though the age of the lowest series of lake deposits in this area is unknown and may be Kageran). This pluvial period was named after the Kagera river in Uganda, where Wayland first found terraces at heights of 270, 220, 110, and 30 feet above the present river. The highest terrace is of Kageran age and contains pebble tools of the Earliest Kafuan stage (Van Riet Lowe 1952:28). In western Kenya, clays and tuffs at Kanam were laid down during the Kageran pluvial. They are associated with a Villafranchian fauna, which includes true elephants and horses as well as relics of Tertiary times such as Dinotherium, Anancus, Stegodon, Stylohipparion, etc. A similar fauna is found