Graveyard DNA rewrites African American history
16 September 2010 by Shanta Barley
Two of Christopher Columbus's shipmates were the first Africans to set foot in the New World, a study has found.
Using DNA analysis of human bones excavated from a graveyard in La Isabela, Dominican Republic – the first colonial town in the Americas – the new study adds weight to the theory that Africans crossed the Atlantic at least 150 years earlier than previously thought.
"African Americans have come to believe that their history began when the first slave ships docked in the mid-17th century, but our results suggest that it actually started far earlier, at the same time as the Europeans' history on the continent did," says Hannes Schroeder of the Centre for GeoGenetics at the University of Copenhagen, Denmark, who did the analysis.
La Isabela was founded in 1494 on Columbus' second voyage to the New World. Seventeen ships deposited 1700 people – including farmers, builders and priests – on the part of the island of Hispaniola that today is the Dominican Republic. Within two years, all but 300 had died of starvation and disease, and in 1498 the town was abandoned.
Last year, one of Schroeder's collaborators, Douglas Price, from the University of Wisconsin-Madison, suggested that up to seven of the 49 skeletons exhumed from La Isabela's 15th-century graveyard had belonged to Africans. The carbon and strontium isotope ratios in their tooth enamel, which give clues to an individual's diet, pointed at possible African origins for the seven.
To investigate whether Africans were indeed among those buried in La Isabela, Schroeder studied a thigh bone and a premolar tooth from each of 10 skeletons dug up between 1983 and 1991, including the seven earmarked as African by Price's analysis.
After extracting DNA, Schroeder searched for key segments of mitochondrial DNA that differ between people of African and non-African descent, and found that two of the individuals carried DNA segments that are most frequently found in sub-Saharan Africans. Schroeder concludes that two of Columbus' crew almost certainly hailed from Africa.
Tina Warinner of the Institute of Anatomy at Zurich University, Switzerland, says Schroeder's rigorous methods mean the result is unlikely to be an artefact. Schroeder plans to analyse a new set of La Isabela skeletons to be exhumed next year.
DNA analyses will never reveal whether the Africans who were laid to rest at the church of La Isabela were slaves or free men who joined Columbus' expedition of their own volition, says Schroeder. But by studying their nuclear DNA, he hopes to find out exactly where in sub-Saharan Africa their families came from. "Now that would be pretty cool," he says.
The team presented their findings at the Fourth International Symposium on Biomolecular Archaeology in Copenhagen, Denmark, last week.