Increasing biocultural diversity of historical ‘African’ populations: two case studies using morphometrics and various contextual data.

The continuing excavation of numbers of historic cemeteries has resultedb in human bioarchaeology developing a research interest in the analysis of historical populations dated to the last three centuries. These cemetery samples typically show a large amount of biological diversity but often the geographical origins of the parent populations are not well understood. Each discovery is unique in terms of time and historic context. In particular the urban context has been impacted by the large scale mobility of human populations, especially in relation to the slave trade, and is a reflection of the increase in the biocultural diversity in humans during the historic period. These historical phenomena, especially the slave trade, are explored here, focusing on two human skeletal collections that are supposed to reflect high biological and cultural diversity and not only of African origin. The specimens under study originate from two different contexts of discovery: the Cobern Street burial ground (late 18th century, Cape Town, South Africa, N = 39), and some of the Samuel G. Morton’s collection labelled ‘African’. The first collection is relatively well documented in comparison to the second whose origins are only suggested by the archives (19th century, Cuba, N = 38). Craniometrical multivariate analyses are performed using up to 16 standard variables, and the two samples are compared to worldwide variation (various regions of Africa, Asia, Europe). The comparative groups are chosen to be intentionally variable in order to test specific hypotheses in relation to the historical context of each collection. Preliminary results show very high levels of diversity in both Cobern Street and Morton’s Collection samples, supporting the hypothesis of the presence of high levels of gene flow not only of African origin. They support historical data available on the slave trade, as well as the recent genetical data showing extreme diversity in present-day Cape Town populations (partly considered as Cobern Street descendants).