Monte Verde Archeologist Prevails In Dispute Over Settlement's Age

Tom Dillehay's claim that the Chilean site is the oldest known New World excavation finally gains acceptance Thirteen years ago, archeologist Tom Dillehay was teaching at the Universidad Austral de Chile in Valdivia and pursuing his interest in early Andean cultures. Then a student asked the young researcher to identify several large bones found at Monte Verde, a wet and boggy site in south central Chile. Dillehay recognized the bones immediately as belonging to a mastodon. Dillehay had no wa

By | January 20, 1990


Tom Dillehay's claim that the Chilean site is the oldest known New World excavation finally gains acceptance
Thirteen years ago, archeologist Tom Dillehay was teaching at the Universidad Austral de Chile in Valdivia and pursuing his interest in early Andean cultures. Then a student asked the young researcher to identify several large bones found at Monte Verde, a wet and boggy site in south central Chile. Dillehay recognized the bones immediately as belonging to a mastodon.

Dillehay had no way of knowing that his exploration of the site where the prehistoric animal had been butchered by Indian hunters would challenge long-held theories about the peopling of the Americas - or threaten his own budding career.

"What we found was really the best window we've ever encountered on the ways of early hunter-gatherers. It's the Machu Pichu of the Ice Age," says Dillehay, now at the University of Kentucky, Lexington. Other archeologists are equally enthusiastic, calling Monte Verde "the most important site [in the Americas] to come along in the last 60 years." For beneath the peaty bogs of Monte Verde lie 14 wooden hut foundations, wood and stone artifacts, a hunk of preserved mastodon muscle, animal skins, and masticated potatoes. There is even a human footprint.

But an ancient habitation wasn't the only thing that Dillehay uncovered. His discovery plunged him unwittingly into a bitter and protracted debate among archeologists over the date of the first human settlement in North America. Most archeologists, based on evidence from a 1927 discovery in New Mexico, believe that the first humans came to the New World 12,000 years ago. In fact, adherence to that view has become almost a litmus test for acceptance into the profession. Unfortunately for Dillehay, many of the artifacts from Monte Verde date from 13,000 B.P. (before the present). And that 1,000-year difference would force him to wage a 10-year battle to preserve his professional reputation.

Until the 1927 discovery of an arrowhead lying among the bones of a mammoth found at Folsom, N.Mex., archeologists hotly debated whether prehistoric peoples had inhabited the Americas even 5,000 years ago. The Folsom discovery pushed the date back to 12,000 B.P., and there it has remained, in spite of the abundance of archeological sites that have been offered as proof of earlier settlement. In addition to Monte Verde, the past and present contenders include:
  • Calico Hills, California. Excavations of stone artifacts began here in 1964 under the direction of Ruth Dee Simpson and the late Louis Leakey. Artifacts from one layer have been dated at between 15,000 and 20,000 years ago; those from another level, at 200,000 years ago. But the stone tools have always been questioned. They appear to be simple choppers, but because the site itself is located on an alluvial fan where the ground is unsettled, many geologists and archeologists have argued that the tools are nothing but "naturefacts" - tools made by Mother Nature. Simpson continues to work the site.
  • Old Crow Basin, Yukon Territory. Four bone tools were recovered along the Old Crow River in 1966 by William Irving of the University of Toronto. Originally dated at 30,000 years, they were recently tested again with an accelerated radiocarbon method. The new date: 1,300 years old.
  • Meadowcroft Rock Shelter, Pennsylvania. James Adovasio of the University of Pennsylvania carried out extensive excavations here between 1973 and 1977, using a multidisciplinary team of geologists, archeologists, and botanists, and established that the cave was occupied from at least 12,000 years ago to 700 years ago. But a lower occupation level (stone tools, flakes, charcoal bits, and a basket fragment) has yielded radiocarbon dates ranging from 19,600 to 13,240 years. This latter material remains controversial, with skeptics arguing that the charcoal (which was used to obtain the dates) may have been contaminated by groundwater movements. Researchers have called for further tests.
  • Pedra Furada Rock Shelter, Brazil. One of the newest entries in the "early humans in North America sweepstakes," Pedra Furada was discovered in 1973 and has been excavated by French archeologist Niede Guidon. There are five distinct sedimentary layers in the rockshelter, with each containing artifacts and hearth structures. The upper levels have been dated at about 8,000 years ago, while the lowest level has yielded a date of approximately 32,000 years. But again, the geology has been called into question.
  • Monte Verde II, Chile. Tom Dillehay has uncovered primitive stone tools and bits of charcoal that have been dated at 33,000 years old, some two miles from the main Monte Verde site, and buried several meters deeper. Dillehay himself remains uncomfortable with this material, and has left it open to discussion. "If Dillehay got embroiled over the 33,000-year date and then it was dismissed, that would be the end of Monte Verde," says SMU archeologist David Meltzer. "So it's a smart strategy to get the 13,000-year-old stuff past the buzzards first. Then he can worry about the later site."

--V.M.

Dillehay's discoveries earned him a National Geographic Society (NGS) grant to begin an excavation in 1979. But he almost immediately ran into trouble. Just before Dillehay began digging, NGS dispatched Junius Bird to examine the site. An eminent archeologist and curator at New York's American Museum of Natural History who died in 1982, Bird had made dramatic discoveries in Chile in the 1930s, almost single-handedly investigating that country's prehistory. As an elder in the field, Bird was regularly called on to verify new sites. "Monte Verde was probably just another one on his list," Dillehay notes.

Unfortunately, Bird arrived before Dillehay had removed the surface debris and so saw only a mass of logs and a few mastodon bones. No artifacts or stone flakes were visible. From that visit Bird concluded that Monte Verde was not an archeological site. "Junius visited us a few months later," recalled Alan Bryan, an archeologist at the University of Alberta in Edmonton, "and he told us then that Monte Verde was not a site." Bird gave the same report to the National Geographic, and Dillehay's funding dried up.

"Maybe Bird's rejection was a good thing, because it made us push harder," Dillehay says now. But even after Dillehay had opened the site and began recovering indisputable archeological remains, Monte Verde remained tainted. Adding to the burden from Bird's denunciation, the radiocarbon dating on the organic remains came back as 13,000 B.P.

Scientists responded with deep-set skepticism. "Any time any one mentions a date before 12,000 B.P., you can just feel the hair rise on people's necks," explains David Meltzer, an archeologist at Southern Methodist University and an authority on the peopling of the Americas. Since the 12,000 B.P. date was established in 1935 following the discovery in New Mexico of projectile points and hunting camps known as the Clovis culture, every effort to push the date beyond that point has met with failure (see accompanying story).

"Time and again sites have been offered and they just don't pass muster," says Meltzer. Thus, he claims - "in spite of the suggestion that New World archeologists are unable to look at an earlier date because of some congenital reason" - the skepticism has been justified.

Over the years, New World archeologists have generally divided into Clovis and pre-Clovis camps. The dispute between the two has become so emotionally charged that one scientist likens it to "arguing with creationists; it's that kind of an entrenched position." Notes another, "It goes beyond science. It's just being human."

But unlike many of the archeologists involved in the dating debate, Dillehay had not been searching for early sites in the Americas and did not have a professional stake in the argument. Monte Verde came to him "by chance," he says.

"I just happened to be there, and I didn't really want to get involved. I even tried to give that site away," he says. He was as surprised as his colleagues when the date came in at 13,000 B.P. Dillehay was also unprepared for the cold shoulder his reports elicited at archeological meetings.

"I started giving lectures on Monte Verde in 1981," says Dillehay, "and people always responded by saying, `But aren't the dates controversial? Why would we want to look at these things?' And I'd say, `Forget the dates. This is some of best-preserved material we've had from a hunter-gatherer site. Look, here's a human footprint!' And they could hardly bring themselves to look at it."

Between 1981 and 1986, Dillehay estimates, he gave some 50 lectures at which he met with this response. "I'd just leave them laughing," he says. "But, I mean, so what if it dates to pre-Clovis times? The date shouldn't detract from the cultural value of the material. Still, it shows how the power of a single priority - in this case the date - can suppress other equally important issues."

Rather than aligning himself with either camp, Dillehay decided to focus his study on what he believed was Monte Verde's greatest significance: It was the best example ever discovered of an early Andean culture. Working with what he calls "spaghetti budgets," he called in a variety of experts - geologists, entomologists, palynologists (scientists who study fossilized pollen), paleontologists, botanists - to help him understand what he was discovering. Dillehay also sought the advice of his critics. "I'd say, `Help me out; you're an expert, too. What do you make of these wooden tools? And how can we sort out these dates?' I think that allowed people to be less defensive. They could see I hadn't drawn any lines."

Dillehay never received a substantial grant for Monte Verde. Instead, he "begged, borrowed, and stole" to finish his excavations. But his greatest disappointment was the fact that none of his Chilean colleagues - in fact, no Chilean archeologist - ever visited the site. Apparently, Bird's initial report convinced many of them that Monte Verde was unimportant. And the subsequent debate over dating scotched any remaining interest.

Alan Bryan and Robson Bonnichsen, North American archeologists who have worked extensively in South America, report that their Southern colleagues refuse to get involved in sites older than 12,000 B.P., fearing that their grants will be cut off. But neither man would name names. "That would just not be cricket," said Bonnichsen.

In spite of the hostile reception, Dillehay persevered. By 1986, his team had pieced together a picture of Monte Verde in Ice Age times, revealing a settlement of people who lived along the banks of a stream, hunting and gathering, raising potatoes, and perhaps trading with other peoples who lived in the Andes and on the coast. In time, too, Dillehay published his discoveries, proving that Monte Verde was, if not absolutely the first site to break the "Clovis barrier," at least the most likely candidate. A site visit by the staunchest pre-Clovis critics may even be in the works, triggered by a letter Dillehay wrote to Science magazine last fall (245:1436, 1989) that chided his critics for not visiting the site in person.

While criticism of the date has faded, questions remain about the significance of the archeological material. "Dillehay's site is well-dated," says Thomas Lynch, an archeologist at Cornell University and a leading pre-Clovis skeptic who has worked extensively in the region. "The problems now are with the artifacts. What horizons do they come from? Do they fit together in a cultural context?" Lynch and others believe that a site visit would resolve these questions.

That skepticism is understandable, notes SMU's Meltzer. "There's a time lag between when you find stuff and when your colleagues actually find out about it," he says. "Dillehay's site is very extensive, very complex, and people aren't going to be convinced by a 20-minute lecture. But now, he [Dillehay] has a number of papers out and a book [Monte Verde, volume I: Palaeoenvironment and site context, Smithsonian Institution, 1989], and people can examine his data and evidence. That's when a scientific debate really starts - when the material is published."

Dillehay accepts Meltzer's analysis and has no hard feelings about the way his colleagues snubbed him in the past. "It's like a fog curtain has finally lifted," he says. "And now that the date is pretty well accepted, people are looking at my discoveries and saying, `This is fantastic. You must be really pumped up.'

"But they don't realize that I found these things years ago - in 1979 and 1983. They were thrilling when I found them, but they're old discoveries to me now. I'm ready to move on to something else."

Virginia Morell, a science writer based in Ashland, Oreg., is working on a biography of the Louis Leakey family for Simon & Schuster.

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