In the Busia district, at the foot of Mount Elgon in western Kenya, lies Kakapel, a granite rock shelter and a national monument since 2004. Its walls preserve one of the most complex sets of rock art in East Africa. The site had been described for the first time by Osaga Odak in 1977, but the documentation had remained partial: his survey covered only the clearest images of the central panel and hypothesized two styles produced by two distinct groups. The discovery allows us to review our knowledge of African prehistory.
A new study published in Azania: Archaeological Research in Africasigned by Catherine Namono and Benjamin Smith, presents the first millimetric survey of the main panel, the result of two weeks of field work in November 2011. The survey made it possible to identify images not detected by Odak and to distinguish four layers of paint instead of the two initially hypothesized.
The four layers correspond to as many phases of occupation documented by excavations, which cover approximately 9,000 years: from the prehistoric Kansyore tradition of fisher-gatherers producing ceramics (7000-2000 BC), through the Early (300 BC – 200 AD) and the Late Iron Age (800-1700 AD), up to the pre-colonial era.
The most relevant contribution of the study concerns the identification of the authors of the rock art. By combining analysis of rock art with ancient DNA from skeletons found in the excavations, the researchers linked each layer to a specific group. The oldest layer, composed of geometric patterns in red and white similar to Twa rock art (Pygmies of Central Africa), is attributable to a pygmy group with genetic affinities with the Mbuti (pygmy people living in the current Democratic Republic of Congo) of Central Africa. The subsequent layers are associated respectively with the arrival of the Bantu farmers (the main ethno-linguistic group of East Africa), the Kalenjin shepherds (a group living in present-day Kenya) and the historical populations of the Teso-speaking area (who arrived in the area between the 16th and 19th centuries.
The authors warn that the connection between pictorial layers and phases of occupation is not mechanical: some groups of those who occupied the rock shelter may have painted without leaving significant archaeological traces, or vice versa. The fact remains that Kakapel is today one of the few sites in the world where it is possible to link cave paintings to specific human groups, genetic profiles and precise chronological periods.
