Bones of contention

Stephen McNallen, a former member of the Viking Brotherhood and more recently a founder of a group calling itself the Asatru Folk Assembly (both groups are dedicated to reviving a form of Norse religion), read that "Caucasoid" description in the New York Times and promptly demanded the bones, claiming Kennewick Man as his people's ancestor. He maintained that the remains were proof that Caucasians came to the Americas before the people now known as Native Americans, justifying his idea that present-day whites have a more legitimate -- or at least a longer-standing -- claim to the American continent than the people who were living on it when Columbus arrived.

Even before this, many Native Americans had been hostile to any suggestion that they had not always lived on the land they occupied. Some were even moved to repudiate what is known as the "Beringian Walk" theory, which holds that Native Americans first came to the Western Hemisphere during the last ice age, around 12,000 years ago, over a land bridge that then existed across the Bering Sea, between eastern Siberia and western Alaska. According to Dewar, many Native Americans believe the story of the Beringian Walk is "ridiculous" and that it was invented to make them look like "just another group of immigrants," undermining their primary claim to the land.

Dewar is sympathetic to this view, and her sympathy leads her to spend a great deal of "Bones" discussing evidence that she thinks disputes the "Beringian Walk" theory and a corollary of it known as "Clovis First." Clovis First holds that the earliest immigrants to North America were members of a Paleoindian culture that arrived in the Great Plains no earlier than about 11,500 B.P. and made a certain kind of arrow point first found near Clovis, New Mexico.

Dewar's contention is that there is a scientific conspiracy afoot against people who come up with evidence that calls these theories into question. She claims that the work of "dissenters" is being unfairly dismissed or sabotaged by the scientific establishment, which she equates with upholders of Beringian Walk and Clovis First orthodoxy. The suppression of contrary evidence, she says, has huge ramifications for Native Americans, who have major spiritual and political stakes in how their New World origins are explained.

It certainly makes a good story -- lonely scientific Davids supporting the birthright of native peoples vs. a monolithic conceptual Goliath intent on devaluing or displacing them. But in seeking scientific drama, Dewar overlooks research and explanations that many scientists believe can reconcile the Beringian Walk with the newer evidence she claims disproves it.

"Juicy journalistic anecdotes or innuendoes can be pulled out of all scientific hats," says Jacques Cinq-Mars, an anthropologist at the Canadian Museum of Civilization in Hull, Quibec, who has done extensive field research in far northwestern Canada, an area that is called "eastern Beringia" in scientific literature. But he thinks that such conspiracy theories tarnish the general public's perception of science, and muddle its understanding of how scientific consensus is formed -- and reformed.

Cinq-Mars doesn't perceive any immovable colossus of universally accepted theory standing astride the field. In fact, he says, "the 'Peopling of the New World' aficionados are in a state of disarray," and "there is an ongoing rush on the part of many to switch ships." Some scientists want to jump off the Beringian land bridge and grasp at alternative theories that Cinq-Mars calls "floating straws," such as a newer coastal migration model that envisions Paleoindians paddling lickety-split down the west coasts of North and South America, or a trans-Pacific theory that -- shades of Kon-Tiki -- sees Polynesians sailing to Peru thousands of years before they made it to Hawaii.

It's true that the Clovis First and Beringian Walk theories were once virtually sacrosanct. In the latter 19th and early 20th century they seem to have been respected as much for saying what the white and powerful wanted to hear as for representing any objective, provable truth. And they were so confidently promulgated by leading scholars that they sailed into the scientific mainstream -- and museum dioramas and school curriculums -- as a kind of secular gospel, with, at that time, relatively little hard evidence to back them up.

As hard evidence has accumulated over the years, some leaks have appeared below the waterline of that faith. Yet there's really no need to look for a life raft -- or a Polynesian outrigger -- to save it. The Beringian Walk theory isn't sinking as Dewar contends, but it is undergoing extensive repair, which can be a confusing, inconvenient process for the people on board.

The evidence and basic arguments Dewar covers (challenges that I call "Too Much Too Soon," "Turd Worms," "No Exit" and "Three Thousand Faces of Eve") are all too weak or too readily explainable to require abandonment of the Beringian Walk theory.

Too Much Too Soon

While the onetime existence of the Beringian land bridge isn't being seriously challenged, the question of when humans first plodded across it certainly is. In particular, the Clovis First idea, which essentially claims that the migration from Siberia couldn't have occurred until around 12,000 B.P., is very much adrift these days because of the growing evidence that humans established communities from the Yukon down to the southern tip of South America at much earlier dates. Jacques Cinq-Mars excavated a series of caves in the Yukon and uncovered a tool made from mammoth bone that appears to have been buried a little less than 25,000 years ago. In far south Chile, American archaeologist Thomas Dillehay, working under the auspices of the National Geographic Society, found a human settlement that made sophisticated use of a wide variety of plant materials at least as early as 12,500 B.P. Some sites in eastern Brazil seem to date from even earlier.

Next Page: The 200,000-year-old mother of us all

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