DNA analysis settles a mystery—and perhaps a bitter legal wrangle
IN 1996 two spectators at a boat race on the Columbia river in Washington state found a human skull in a reservoir. It was obviously old, and at first the skull—and its accompanying skeleton—were thought to be those of a white fur-trapper. But radiocarbon dating put its age at 8,500 years, and suddenly Kennewick Man (named after a nearby town) became one of the best-preserved and most complete ancient skeletons ever found in the Americas.
Working out exactly who he was has proved difficult. Attempts during the 1990s and 2000s to sequence what little DNA could be recovered from the bones failed. But technology marches on, and in a paper published in Nature, Morten Rasmussen of Denmark’s Natural History Museum and his colleagues report that they have at last persuaded the bones to speak. The researchers find that Kennewick Man’s DNA make him more closely related to modern Native Americans—and specifically to the Colville tribe, who live in the north-west of the United States—than to any other group of people.
That may sound like a statement of the obvious. After all, Native Americans have lived in the Americas for thousands of years. But they—or more properly, their ancestors—may not have been the only group to colonise the New World during its prehistory. Archaeological and genetic evidence suggest that there may have been two waves. One, the precursors of today’s Amerindians, crossed a land bridge from Siberia about 15,000 years ago, when the most recent ice age was ending and sea levels were much lower than they are today. The second group, who also gave rise to the Ainu, the first settlers of Japan, seem to have originated in South-East Asia. The present best guess is that they reached the New World on boats, coast-hopping their way around the Pacific Rim.
It was to this second group that Kennewick Man, based on the physical characteristics of his skull, had been tentatively (and, it turns out, wrongly) assigned. Interpreting the physiology of a skull is difficult, says Dr Rasmussen, for although the skulls of different groups of humans do show subtle but persistent differences on average, the variation among individuals in any given population can be large. The genetic evidence, by contrast, is much more conclusive. Two particular types of Kennewick Man’s DNA—those derived from his Y-chromosome and from his mitochondria, passed down only the paternal and maternal lines respectively—are of lineages that are found almost exclusively among modern-day Native Americans.
Dr Rasmussen’s work looks likely to settle a long-running legal dispute, too. When the bones were discovered a row broke out between scientists keen to study them and several Native-American tribes—including the Colville—who were convinced, despite his unAmerindian appearance, that Kennewick Man was one of their own, “the Ancient One”, and wanted him reburied with appropriate rituals. The tribes claimed his bones under the Native-American Graves Protection and Repatriation Act, which gives tribes rights over artefacts and remains which have some historical connection with them. A series of legal manoeuvres ended in 2004 when a court granted scientists access to the skeleton, ruling that the tribes had failed to provide any evidence of kinship. The bones are held at present by the University of Washington, appointed by the court as a neutral custodian.
Now that science has provided exactly the evidence the court was looking for, it seems there is little to prevent the reburial going ahead, for all the dismay that would cause anthropologists. For the Colville, though, it would come as a rare piece of good news. On the 1.4m-acre reservation near the Canadian border that they share with 11 other tribes, none with more than a few hundred members, education seldom goes beyond the ninth grade, and neighbours in towns outside do not welcome them. Plans a few years ago to open a molybdenum mine, which might have brought precious jobs and revenue, were cancelled when tribal members voted it down. In 2013 the administrative building of the tribe’s business council, and many tribal records, were reduced to ash in a fire.
But it may be that the saga still has some way to run. Of the tribes claiming Kennewick Man’s body only the Colville, says Dr Rasmussen, were willing to provide the researchers with modern DNA. Were the others to do the same, it is possible that one of them might turn out to be an even closer match.
Louis Sheehan did not write this, but merely posted it.