[LINK] "Tracing Slaves to Their African Homelands"

[rfmcdonald]

National Geographic's Andrew Lawler reports on technological advances, including DNA, which are allowing researchers to discover the origins of slave populations throughout the Atlantic world.

“This will change our understanding of population and migration histories,” says Hannes Schroeder, a biological anthropologist at the University of Copenhagen. “What was just potential is now being fulfilled.”

One example comes from a 17th century cemetery on the Dutch side of the Caribbean island of St. Martin. When archaeologists excavated the site in 2010, they noticed filed teeth in the skulls of two men and a woman. The three individuals were between 25 and 40 years old when they died in the late 1600s.

Since teeth filing was a common practice in sub-Saharan Africa, it was a good bet that the individuals were enslaved Africans brought to the colony in the days of sugar plantations.

Just five years ago, that would have been the end of the story. An attempt to extract DNA from the skeletons to learn more about their identity would have been quixotic, since hot and humid weather degrades genetic material.

“These were badly preserved,” said Schroeder. “They had been laying under a Caribbean beach for four hundred years.” By contrast, biologists in 2012 readily sequenced the entire genome from Otzi, the frozen “ice man” who died in the Alps five thousand years ago.

After months of careful work, however, Schroeder’s team was able to extract DNA from the St. Martin individuals using a new procedure called whole-genome capture. Devised at Stanford University in California, this technique concentrates the degraded genes, providing enough material to sequence.

By comparing the results with a database from modern-day Africans, the researchers determined that all three people came from different parts of that continent. One of the men likely came from what is today northern Cameroon, while the other man and the woman may have originated in Ghana or Nigeria to the south.