Abstract:
The late Pleistocene and Holocene history of eastern Africa is
complex and major gaps remain in our understanding of human
occupation during this period. Questions concerning the
identities, geographical distributions and chronologies of foraging,
herding and agricultural populations — often problematically
equated with the chronological labels ‘Later Stone Age (LSA)’,
‘Neolithic’ and ‘Iron Age’ — are still unresolved. Previous studies
at the site of Kuumbi Cave in the Zanzibar Archipelago of
Tanzania reported late Pleistocene Middle Stone Age (MSA) and
LSA, mid-Holocene Neolithic and late Holocene Iron Age
occupations (Sinclair et al. 2006; Chami 2009). Kuumbi Cave
considerably extends the chronology of human occupation on the
eastern African coast and findings from the site have been the
basis for the somewhat contentious identification of both a
coastal Neolithic culture and early chicken, a domesticate that
was introduced to Africa from Asia. The site therefore warrants
further investigation. Here we report on a new excavation of the
Kuumbi Cave sequence that has produced a suite of 20
radiocarbon and optically stimulated luminescence (OSL) dates.
Our results suggest that the cave’s stratigraphy is complex,
reflecting taphonomic processes that present interpretive and dating challenges. Our assessment of the stratigraphic sequence
demonstrates three phases of habitation, two of which reflect
terminal Pleistocene occupation and are characterised by quartz
microliths, bone points and the exploitation of terrestrial and
marine species, and one of which reflects later reoccupation by
AD 600. In this latter phase, Kuumbi Cave was inhabited by a
population with a locally distinct material culture that included
idiosyncratic Tana or Triangular Incised Ware ceramics and mediumsized
limestone stone tools, but with a subsistence economy similar
to that of the late Pleistocene, albeit with more emphasis on marine
foods and smaller terrestrial mammals. Our results suggest that
Kuumbi Cave may have been unoccupied for much of the
Holocene, after Zanzibar became an island. Our findings also place
into question earlier identifications of domesticates, Asian fauna and
a mid-Holocene Neolithic culture at the site.
