In 1976, workers digging a road along the marshy banks of a creek in Monte Verde in southern Chile unearthed the remains of a prehistoric campsite that might contain the oldest known human artifacts in the New World.
Scientists who have examined the artifacts contend that the his-torical record of the Americas will have to be rewritten to reflect the new finds.
"These were truly dawn peo-ple," said Tom Dillehay, an American anthropologist who headed up the initial investigation for the Southern University of Chile in Valdivia. "We might think of them as Adam and Eve in the New World."
Most archaeologists have accepted the theory that the first humans to reach the Americas trekked across the Bering land bridge from Siberia less than 12,000 years ago. Called the Clovis people, they were named after a site in New Mexico where archaeologists first found a fluted stone spearpoint that has become their signature.
But radiocarbon testing of stone weapons, mastodon bones and hundreds of other artifacts at the Monte Verde site indicates the region might have been home to prehistoric wanderers at least 1,000 years earlier. The most startling discovery was that of a tiny human footprint. Measuring about 5 inches from toe to heel, the footprint probably belonged to a small child, said Dr. Dillehay.
Excavators also found remnants of some 45 edible plants. More than one-fifth came from regions as far as 150 miles away, indicating that the Monte Verdeans either ranged far or traded with other groups.
"The amount of plant foods we found at the site - notably wild potatoes, bamboos, mushrooms and juncus seeds - was astounding," said Jack Rosen, an ethnobotanist from Ithaca College who helped study the site. "Their harvest of these plants approaches true agriculture."
These and other prehistoric finds in the region contradict conventional theories about mankind's relative newcomer status in the New World, according to David Meltzer, an archaeologist at Southern Methodist University in Dallas.
"How could people possibly have reached all the way down there from Alaska in a few hundred years?" he asked recently. "They were pioneering a landscape that was becoming increasingly unfamiliar as they moved south. They had to find water and figure out which plants and animals were edible, useful, harmful or even fatal.
"They had to cross formidable barriers and cope with new diseases. And they had to do all this while raising families on a vast continent devoid of other people. All of that takes time."
Linguists and geneticists have pointed out that American Indians are too rich in languages and genetic diversity to have had a common ancestry only 12,000 years ago.
Since Monte Verde suggests that people were in the Americas earlier, how and when did they arrive? Could they have skirted the glaciers, coming down along the coast by boat from Alaska? Or could they have migrated through a narrow corridor that might have separated the ice sheets in eastern British Columbia?
Sailing across the Pacific from Asia to South American in numbers large enough to colonize seems too difficult a journey for primitive seafarers, according to Dr. Meltzer. A more likely explanation, he said, is that they migrated into the lower reaches of North America even before the ice sheets developed more than 20,000 years ago.
Indeed, a second site at Monte Verde has revealed stones that may have been flaked by human hands 33,000 years ago.
Syndicated columnist Randall Floyd lives in Augusta.