Dating in malawi
DNA analysis revealed that the baby was a girl and radiocarbon dating showed she had died about 2,500 years ago.
The analysis also showed that the bones from the infant and the two men were from the same hunter-gatherer population—even though they were separated by thousands of years of time.
Thompson, the paper’s second author, contributed and described the cultural context for nearly half of the 15 new DNA finds, including the oldest samples.
Her fieldwork in Malawi uncovered two human leg bones that yielded 6,100-year-old DNA—and her work is ongoing at a site where a newly dated skeleton with 8,100-year-old DNA was recovered several years ago.
It is one of the least-developed and smallest countries in Africa, about the size of the state of Tennessee, and runs north to south along the Rift Valley.
An enormous body of water, Lake Malawi, makes up about one-third of the country. On the slopes of Mount Hora—a 1,500-meter peak and a major landmark in the highlands—Clark uncovered two skeletons: A woman who had died at around age 22 and a nearby male, who had died in his 40s.
When anthropologist Jessica Thompson attended a human origins conference years ago, she heard a presenter lament: “Of course, there is no ancient DNA from Africa because of the poor preservation there.” That’s when something clicked in her mind: In 2005, she had visited Malawi, a place in Africa that had neither extremes of heat or wetness—two main environmental factors that degrade DNA.
“When you visit the site,” Thompson says, “you wonder, why were these people living up here when it’s not the most comfortable conditions you can imagine? Why were they burying their dead, over and over again, for many thousands of years, in the same place?
” Thompson tracked down the skeletons that Clark had discovered at Mount Hora in 1950.
Two digs in the Malawi highlands—in 19—revealed human skeletons alongside rich cultural evidence of an extinct hunting-and-gathering lifeway. The skeletons had been taken out of the country, to the Livingstone Museum in Zambia, and were never dated.
“It was impossible to accurately do radiocarbon dating on bone in 1950,” Thompson says.