Between 1500 and 1850, more than twelve million Africans were brought in chains to the New Word to grow labour-intensive crops such as sugar, cotton, tobacco and rice. Historical records often contain the date of departure of the slave ships, the African port of embarkation, and final destination, but little information about the people they transported. Aside from their ancestry in West Central Africa, it was difficult to know their ethnic or geographic origins.
In 2010, construction work in Sint Maarten excavated the remains of two men and a woman. Skeletal analysis of the “Zoutsteeg Three”—named for the area in which they were found—indicated they were African, and radiocarbon dating indicated they were buried in the late sixteenth century. Although the DNA in the remains was poorly preserved in the tropical Caribbean climate, researchers were able to collect enough genome-wide data to trace their origins to different regions in Africa.
DNA was extracted from their tooth roots, sequenced and compared to that in reference genomes collected from eleven different modern West African populations. One of the men appeared to be from the Bamoun, a Bantu-speaking group in northern Cameroon, and the other two slaves came from non-Bantu-speaking groups in the Nigeria and Ghana region. Of course there have been migrations within Africa in the meantime; these modern populations may not be the same as the populations that lived in these locations during the Atlantic slave trade.
These findings provide the first genetic evidence of the ethnicity of slaves dragged to the New World. It is especially noteworthy that these three slaves came from different places, as only one slave ship is recorded to have arrived in Sint Maarten at that time (although there were probably some that were not recorded).
But that is not the primary interest of this article. While the results are interesting, the paper really serves as a proof of concept that ancient DNA can be used to answer historical questions. Sequencing methods are now so sensitive and robust that there doesn’t have to be much of the DNA, and it doesn’t even have to be of such good quality. This methodology can be especially valuable in archaeological scenarios such as this one, for which historical data is lacking.
PNAS2015. DOI: 10.1073/pnas.1421784112 (About DOIs).