Archaeology of Caves along the East African Coast

Abstract

Caves in uplifted limestone running from southern Kenya to Zanzibar were occupied by hunter-gatherers since the late Middle Stone Age approximately eighty thousand years ago. At that age they were a novel setting for human occupation away from the savannah landscapes of the East African interior. One of these caves, Panga ya Saidi, has yielded the earliest evidence for the Later Stone Age (LSA) anywhere in Africa, beginning sixty-seven thousand years ago. This cave is one of the only sites in Africa to have repeated human occupation throughout the major climatic fluctuations of the last eighty thousand years, a situation facilitated by its ecotonal and near-coastal setting. The rising sea levels after twenty thousand years ago saw more widespread coastal occupations including of Kuumbi Cave on Zanzibar, which was at that time joined to the mainland. A major transition in the occupation histories of the caves occurs in the late 1st millennium ce, with Iron Age ceramics appearing at many cave sites on the mainland coast and offshore islands, where they become increasingly prevalent into the 2nd millennium. The colonization of offshore islands occurs alongside the first definitive evidence for human occupation in Madagascar, including foragers living in cave sites. On both the mainland and offshore islands a continuing tradition of stone tool manufacture persists with the occasional use of domestic crops and livestock, demonstrating interactions between foraging and early farming communities. Glass beads show the cave occupants became part of Indian Ocean trade networks, likely exchanging forest products with Swahili merchants. Ancient DNA analysis indicates the survival of ancient hunter-gatherer ancestry well into the 2nd millennium ce. In the early 21st century, many of these caves are venerated as places of the ancestors and other spirit beings.