A multi-component forager-to-herder sequence at Kapsoo Rockshelter (Chebinyiny) on the Uasin Gishu Plateau, Kenya

Early archaeological investigations of the Uasin Gishu Plateau of west-central Kenya highlighted its potential importance as a geographic link between the Central Rift, the Lake Victoria Basin and the western Kenyan highlands from the Middle Stone Age to the Pastoral Neolithic and Iron Age periods. Despite this, the region has seen little focused research in recent decades. Here, we report on archaeological research at the site of Kapsoo Rockshelter, Chebinyiny Hill (GmJf1), near Moiben on the northern end of the Uasin Gishu Plateau. We combine data from original fieldwork in 1982 with renewed test excavations at Kapsoo carried out in 2022. Results of lithic, faunal and material analyses combined with radiocarbon dating reflect occupation of the northern plateau from the late Pleistocene to the late Holocene and provide the first radiometric dates for the presence of mobile herders in this region. Quantitative assessment of the rich lithic record at the site identifies significant technological change over time, providing a description of the regional Later Stone Age sequence. Finally, we present hypotheses for the relationship between Kapsoo and the nearby undated sequence at Muringa, as well as how these records fit into broader patterns of economic change across southwestern Kenya.