Recent revisions of estimates for the volume of the trans-Atlantic slave trade suggest that approximately 11,863,000 slaves were exported from Africa during the whole period of the Atlantic slave trade, which is a small upward revision of my 1982 synthesis and still well within the range projected by Curtin in 1969. More accurate studies of the French and British sectors indicate that some revision in the temporal and regional distribution of slave exports is required, especially for the eighteenth century. First, the Bight of Biafra was more important and its involvement in the trade began several decades earlier than previously thought. Secondly, the French and British were more active on the Loango coast than earlier statistics revealed. The southward shift of the trade now appears to have been more gradual and to have begun earlier than I argued in 1982. The greater precision in the regional breakdown of slave shipments is confirmed by new data on the ethnic origins of slaves. The analysis also allows a new assessment of the gender and age profile of the exported population. There was a trend toward greater proportions of males and children. In the seventeenth century, slavers purchased relatively balanced proportions of males and females, and children were under-represented. By the eighteenth century, west-central Africa was exporting twice as many males as females, while West Africa was far from attaining such ratios. In the nineteenth century, by contrast, slavers could achieve those ratios almost anywhere slaves were available for export, and in parts of west-central and south-eastern Africa the percentage of males reached unprecedented levels of 70 per cent or more. Furthermore, increasing numbers of slaves were children, and again west-central Africa led the way in this shift while West Africa lagged behind considerably.This review of the literature on the demography of the slave trade provides a context to assess the revisionist interpretation of David Eltis, who has argued recently that the slave trade and its suppression were of minor importance in African history. It is shown that Eltis' economic arguments, based on an assessment of per capita income and the value of the export trade, are flawed. The demography of the trade involved an absolute loss of population and a large increase in the enslaved population that was retained in Africa. A rough comparison of slave populations in West Africa and the Americas indicates that the scale of slavery in Africa was extremely large.
Texture contrast soils (TCS) as indicators of eolian dust inputs in the coastal area of west central Senegal, West Africa
