Archaeology of Early Pastoralism in East Africa

The first East African pastoralists arrived at the shores of Lake Turkana soon after the end of the African Humid Period, about 5,000 years ago. In the preceding millennia of the Holocene, fishing economies characterized East Africa. The domestic animals of the early pastoralists were not indigenous to East Africa, nor did they spread through the region simultaneously. Early pastoralist archaeological sites around Lake Turkana comprise settlements and remarkable monumental cemeteries. The expansion of pastoralists further south through East Africa was a two-stage process, probably because of the challenges posed by the presence of diseases fatal to livestock. First, caprines spread south and appear to have been integrated into existing forager subsistence systems. Then, starting toward the end of the 2nd millennium bce, specialized pastoralism began to be established across central and southern Kenya and into northern Tanzania. While analysis of lipid residues on potsherds has demonstrated that these Pastoral Neolithic (PN) peoples milked their animals, the question of whether agriculture was also practiced remains unresolved. Analyses of ancient DNA have shown there were at least two episodes of demic diffusion associated with the spread and establishment of the PN in East Africa. Considerable diversity is present in the PN, with three distinct cultures generally recognized across East Africa south of Lake Turkana. Moreover, there is even greater diversity observed in the decoration and shapes of ceramics. However, this cultural diversity is not matched by human genetic diversity, at least among the analyzed skeletons from two of the three cultures—the Elmenteitan and the Savanna Pastoral Neolithic.