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paleoanthropology, genetics and evolution

Steve Lekson profile

Thu, 2009-07-02 08:30 -- John Hawks

The NY Times profiles Southwest archaeologist Steve Lekson, "Scientist Tries to Connect Migration Dots of Ancient Southwest":

“Steve is possibly the best writer in Southwest archaeology,” said David Phillips, curator of archaeology at the Maxwell Museum of Anthropology at the University of New Mexico. “Our academic writing has this inherent gift of taking something interesting and making it dull and boring. And Steve doesn’t have that problem. He thinks outside the box, and the rest of us comb through his ideas.”

“Having said all that,” Dr. Phillips added, “I personally think that the Chaco meridian is a crock.”

Lekson has a new book coming out, History of the Ancient Southwest, which updates his "Chaco meridian" idea along with many other elements of Southwest archaeology. It seems to me that this is an interesting case study in the power of archaeology to test ideological versus ecological hypotheses -- that in a complex society with long-term occupations and stylistic elements for comparison.

But whenever you're talking about a hypothesis involving ideological causation, there's a tremendous potential for confirmation bias:

“Anyone can take any position and find evidence,” Dr. Phillips said. “Done properly, science means that you stop yourself and figure out what the opposite is — the null hypothesis — and you prove the null hypothesis couldn’t possibly be true. By process of elimination, your desired outcome becomes more plausible. This gets back to Karl Popper. You can only falsify.”

But Dr. Lekson insists that archaeology can advance only by pushing beyond the Popperian ideal, trying to make sense of all the data with plausible accounts of what was happening historically in the ancient Southwest.

“We were trained to treat ancient Pueblo societies like cultures in laboratory petri dishes,” he recently wrote. “Sprinkle the right amount of rainfall on the proper soil and up popped pueblos.” What has been neglected, he says, is an appreciation for the unquantifiable.

What they're talking about is different prior assumptions. How close to a meridian do sites have to be to confirm or reject the hypothesis that they're plotted on the meridian? How much can they overlap before they reject the hypothesis of mass relocation? It depends how committed you are to the idea to begin with -- and that depends on your prior expectations about the role of ideological and ecological forces on complex societies.

As for myself, I'm never surprised when a complicated scenario falls close to the mark. It's the simple ones that get my attention.

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