1Department of Anatomy, University of Otago, 2School of Geography, Archaeology and Environmental Studies, University of the Witwatersrand, 3The Allan Wilson Centre for Molecular Ecology and Evolution, University of Otago, 4Department of Integrative Biology, University of California, Berkeley
Thursday 7, Park Concourse
That domesticated cattle were a significant component of African food-producing lifeways by about 7000 years ago is uncontroversial. Their origins, and their subsequent evolution as they settled across much of the continent remain poorly understood. To contribute to our understanding of the spread and development of Africa’s indigenous cattle we have sequenced complete mitochondrial genomes of archaeological cattle from the Iron Age deposits in the Shashe-Limpopo River Basin and their likely descendants, modern southern African Nguni cattle.
Elaborating on a pattern found by Bonfiglio et al (2012) among Egyptian and Ethiopian cattle, we demonstrate a significant reduction in mitochondrial lineage diversity among southern African cattle compared with those further north. This pattern is likely a consequence of serial founder effects at play as cattle moved south through the continent. Despite other evidence of Indian cattle having been introduced into Africa in substantial numbers, these mitochondrial data give no indication that the impacts of the founder effects were ameliorated by gene flow from Indian breeds.
Finally, we have found evidence that the Late Iron Age cattle mitochondrial gene pool, dating to the early 1800s, does not appreciably resemble that of the modern, and presumably descendant, Nguni cattle. We suggest that this is likely the consequence of a rinderpest panzootic known to have dramatically culled the cattle population in sub-Saharan Africa during the 1880s and 1890s.
This research was supported by the Royal Society of New Zealand Marsden Fund, grant UOO1114 and the University of Otago.