Science is shedding new light on the origins of the earliest people in the Americas. We think we know when they came and how they got here. But questions remain. A professor at the University of Kansas has been using genetic analysis to search for new answers and reveals her research in a new book. Commentator Rex Buchanan takes a look.
Commentator Rex Buchanan is a writer and director emeritus at the Kansas Geological Survey. The Lawrence resident is also coauthor of the book Petroglyphs of the Kansas Smoky Hills.
- This commentary was made possible with assistance and contributions from Dr. Laura Murphy, assistant professor of anthropology at Washburn University. Find her on Twitter at @RockDocGeoarch.
- Jennifer Raff, the KU anthropology professor who wrote Origin: A Genetic History of the Americas, is also on Twitter. Find her @JenniferRaff.
- Rex Buchanan is not on Twitter. : - (
(Transcript)
When did people first come to the Americas? How did they get here? Maybe you think you know the answers to those questions, or at least have a general idea. Still, you’d do well to pick up a copy of a new book called Origin: A Genetic History of the Americas by KU anthropology professor Jennifer Raff.
Raff uses genetic analysis of those first peoples to help piece together the timing and the route of their migration here. For the most part, she agrees with the standard story of movement from northeastern Asia, across the Bering land bridge when sea levels were lower, and into North America. In the process, she debunks other, more outlandish theories of peopling the Americas.
But the story of that migration into North America isn’t as simple as it sounds. Did people come down the middle of North America through an ice-free corridor in the glaciers covering Canada? Or did they stick to the West Coast, hopscotching their way south in boats, relying on the ocean’s abundance for food? Raff says the evidence points toward the coastal route.
The answer to the other question, when did people arrive, seems to be more of a moving target. For decades, archeologists focused on projectile points found with extinct Ice Age animals to help date the arrival of people here. Today, most scholars believe that migration occurred about 15,000 years ago. But physical evidence from several sites has pushed that arrival back in time. One site, in South America, puts it at more than 20,000 years ago. As do some recently discovered human footprints in New Mexico.
Raff likes the 14,000 to 18,000 year time frame, but doesn’t claim those numbers are for sure, in part of because of analysis of the genetic makeup of those ancient people, the kind of genetic analysis that she does.
When I first came to KU, I taught science writing, how to communicate technical information to non-scientific audiences, just what Raff is doing in this book. I told students that people want to read about results, not methodology. They want to know what you discovered, not how you discovered it.
In Raff’s case, though, the methodology is much of the story. She describes the demanding and complex process of gathering DNA from an ancient single human tooth. Her account of capturing and analyzing that DNA in a KU lab, avoiding its contamination with modern DNA, is surprisingly compelling reading, and maybe one reason this book wound up on the New York Times best-seller list.
Another reason may be the sensitivity with which she describes working with Native people. Native Americans have been endlessly studied and questioned, and continue to be treated more as subjects than people. Their remains—bones, graves, sacred objects--have a long history of being handled disrespectfully, or worse, in the name of science.
As a non-native Raff works to understand those concerns, and collaborate with Natives. Her account of that collaboration is instructive reading for everyone who lives on Native land today, which is all of us, whether we’re scientists or not.
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