Is paleogenomics poised to rewrite traditional origin stories? Or is it a high-tech update of old biases about culture?
The New York Times Magazine recently published a fascinating article called “Is Ancient DNA Research Revealing New Truths — or Falling Into Old Traps?” in which Gideon Lewis-Kraus describes how scientists shed new light on the ancestry of the natives of the Vanuatu Islands in the South Pacific. It’s also the story of the different tools we use to establish facts about ancient history, and how we use them to reinforce the narratives we prefer.
Other Humans’ Origins
The islanders had always assumed that the original Melanesian inhabitants of the island were dark skinned travelers from Papua New Guinea who later dealt with migrating populations from Asia. A recent postage stamp even celebrated their heritage with a depiction of the dark natives they thought were their forebears. However, DNA extracted from skulls found in an ancient burial site tells a different story: the original inhabitants of the islands probably came from East Asia and were later joined by Papuan migrants called the Lapita.
This troubled the Vanuatu islanders, who are currently battling immigration and development by the Chinese who appear to be closely related to the islands’ first inhabitants. They worry about having their land claims questioned by populations who may consider the islands part of an ancestral homeland.
Prehistoric Power Plays
However, it’s not only the Vanuatu islanders who need to reconsider old beliefs. The dependence on grand narratives about peoples is one that archaeology has been getting away from. It’s a vestige of the simplistic “settlement archaeology” that inspired the Nazis. The article quotes British archaeologist Colin Renfrew describing this crude approach like this: “Prehistory was seen as a kind of global chessboard, with the various cultures as pieces shifting from square to square. The task of the archaeologist was simply to plot the moves — or, in other words, trace the path of the ‘influence’ as new ideas were diffused.”
Harvard’s David Reich runs the DNA lab that did the analysis on the skulls from Vanuatu, and he seems to describe what his data says in the same terms as Gustaf Kossinna a hundred years ago:
In the broadest conceptual terms, though, [Reich] saw the lessons of this once-enigmatic Lapita migration to be exceedingly profound. “I think the important finding for archaeologists and for historians and sociologists and anthropologists is that this group moved thousands of kilometers over many hundreds of years, through a region occupied by long-established, sophisticated people, and hardly mixed with them.” He observed that “essentially everybody was surprised.” They were surprised, in part, because archaeologists since the 1960s had been trained never to assume the purity or coherence of a people, a slippery slope to the conclusion that certain peoples came by their advantages “naturally.”
But the data seemed indisputable. “Now we can establish that definitively. That’s what this technology allows us to do. And then they” — meaning all those other disciplines, which heretofore had overseen the study of prehistory — “can get on with answering what really matters, which is try to interpret what happened.”
Other researchers involved in the study of the Vanuatu islanders’ history say that’s not solving anything, it’s just leaving all the heavy lifting to the archaeologists: “What Reich was wont to attribute to simple “migration” was just a restatement of the problem of what happened. The actual causal mechanism could have been malaria, or warfare, or volcanic activity, or some competitive advantage in agriculture.”
Dazzled by DNA
Oversimplified and trite though they are, Reich’s theories have a lot of enthusiastic support in the scientific world due to their employment of cutting-edge technology. Reich’s lab is a powerful player in the paleogenomics game, and many researchers say the Harvard lab’s prestige gives it an advantage over smaller labs. The extent to which Reich’s work made “claims that were essentially indistinguishable from the racialized notions of the swashbuckling imperial era” doesn’t seem as relevant as its appeal for an industry and public who think DNA sequencing is a lot more sexy than dusty old bone-hunting. The unprecedented speed with which Reich’s paper passed the approval process at the journal Current Biology, particularly when a rival paper about the Vanuatu matter by a team of conventional archaeologists was scheduled for publication, raises a lot of questions about the politics of peer review.
This controversy is about different philosophical approaches to history and the study of human origins:
The resulting schism has been easy to caricature as the old struggle between hard scientists and humanists — a suspicion of all geneticists as quantitative imperialists, a derision of all archaeologists as sentimental Luddites — but that isn’t quite accurate. Many archaeologists are thrilled about the arrival of the first genuinely new form of prehistoric data in generations. The more meaningful division is between two alternate intellectual attitudes: those bewitched by grand historical narratives, who believe that there is something both detailed and definitive to say about the very largest questions, and those who wearily warn that such adventures rarely end well.
I highly recommend this article for people who are interested in the stories we tell about the past and about how our knowledge develops.