The Oldest Americans Just Got Older

By JOHN NOBLE WILFORD
Published: June 29, 2004, in the New York Times

BARNWELL, South Carolina, June 24 - On a hillside by the Savannah River, under tall oaks bearded with Spanish moss, an archaeologist and a graduate student crouched in the humid depths of a trench. They had reason to think they were in the presence of a breathtaking discovery.

Or at the least, they were on to something more than 20,000 years old that would throw American archaeology into further turmoil over its most contentious issue: when did people first reach America, and who were they?

The sandy soil of the trench walls was flecked with pieces of chert, the source of flint coveted by ancient toolmakers. Some of the stone flakes appeared to be unfinished discards. Others had the sharp-edged look of more fully realized blades, chisels and scrapers. Long ago, it seemed, Stone Age hunter-gatherers had frequently stopped here and, perhaps, these toolmakers were among the first Americans.

With deft strokes of his trowel, the archaeologist, Dr. Albert C. Goodyear of the University of South Carolina, excised a chunk of chert about the size of a cantaloupe. Its sides, he said, had all the marks of flintknappers' work. They had presumably smashed one cobble against another, leaving fracture lines through the rock, and then recovered thin slices for making sharp tools.

"This is not a natural occurrence," Dr. Goodyear said, showing the beaten-about chert cobble afterward. "No river, fire or animals could do this. Too many blows have been struck."

If he is right, American prehistory is being extended deeper in time at this remote dig site near Barnwell. Dr. Robson Bonnichsen, an expert on early Americans who is not directly involved in the excavation, said it could even be "the single most significant Ice Age site in North America" as a place bearing tantalizing evidence for "understanding the earliest prehistory of the Americas."

The land is owned by the Clariant Corporation, the big Swiss chemical company, which allows archaeologists to dig to their minds' content in the forest at the Topper Site, named for the person who brought it to their attention more than 20 years ago.

Judging by the depth of sediments, the site may have been a toolmaking center at least 7,000 years earlier than the arrival of big-game hunters known as the Clovis people. Once thought to be the earliest Americans, Clovis hunters, named for the town in New Mexico where their traces were uncovered 70 years ago, left their finely worked fluted projectile points across the United States over five centuries, beginning 13,000 years ago. All the dates here are based on radiocarbon calculations adjusted to calendar years.

The two men in the trench, their shirts now soaked in sweat, were eager to find evidence that would yield more precise dates for the finds. They leaned into a seam of darker soil interspersed with black grains that the graduate student, Tony Pickering, had found three weeks before. It just might be the remains of a fireplace. If so, any residue of charcoal should give a reliable date through radiocarbon analysis.

Dr. Goodyear emerged from the trench clutching four small plastic zip-lock bags. "I don't know how we ever did archaeology before zip-lock bags," he remarked as he held them up for examination. Each bag contained soil and several pea-size black fragments that he hoped represented the residue of charcoal from a hearth.

"I hope the laboratory gets three dates out of this," he said. "And I hope they're all similar dates."

In his more exuberant moments, Dr. Goodyear ventured that the dates could be as old as 25,000, even 30,000, years ago. He has already found elsewhere on the site what appear to be 16,000-year-old artifacts, evidence for a pre-Clovis peopling of America similar to findings in Virginia and Pennsylvania. None of those discoveries has convinced skeptics.

A few conservative holdouts still question the one widely accepted pre-Clovis claim: that earlier people were living in Chile at a site excavated by Dr. Tom D. Dillehay of the University of Kentucky that is known as Monte Verde. A strong endorsement of Monte Verde by prominent archaeologists published in 1998 encouraged others, including Dr. Goodyear, to dig deeper.

Dr. Bonnichsen, who is director of the Center for the Study of the First Americans at Texas A&M University in College Station and has visited the Topper site and examined some of the possible artifacts, said, "If the preliminary findings hold, this is a tremendous discovery." But he cautioned that "a lot of hard research needs to be done to really test this thing thoroughly."

Dating the putative fireplace will be an important next step. As soon as that is done, Dr. Goodyear said, he and other scientists from several universities expect to announce the age and describe the excavated materials in a journal article, perhaps by the end of the year. Even if the charcoal is from a natural fire, not a human campfire, he said, the analysis should establish the age of any artifacts from the same sediment layer.

A bigger hurdle, scientists said, may be to establish that the stone pieces are indeed human-made tools. Many a presumed pre-Clovis site has failed to gain scholarly acceptance over the question of whether stone pieces that look like tools were the work of early humans or of nature.

Dr. Bonnichsen said much of the 16,000-year-old chert material previously excavated by Dr. Goodyear "looks really good" and might well be tools. At the laboratory at Texas A&M, microscopic examination of the supposed cutting edges showed gouges and scratches that appeared to be wear marks from scraping hides, butchering and cutting wood. They look, he said, "as if they are going to qualify as artifacts."

But it is too soon, he added, to render a nature-versus-culture verdict on the stone pieces from the greater depths and earlier ages at Topper. More experimental work is required to understand how the chert could have been modified into tools.

Dr. Goodyear, whose specialty is the study of stone tools, agreed, though he insisted that "so far we have found no plausible way nature could have made these tools, but we have shown how humans could have made them." The sample collected so far, Dr. Bonnichsen and others said, is too small to be definitive.

Dr. Goodyear said he planned a wider and more intensive search next year. Dr. Sarah C. Sherwood, an anthropologist at the University of Tennessee, is to visit the site next month to investigate the hearthlike material for signs of bone and plant remains, possible evidence for cooking fires, and to determine whether the remains are indeed from a fireplace and are not an accumulation of ash deposited by river floods. Other scientists from Tennessee, Texas A&M, the University of Illinois at Chicago and the Smithsonian Institution have inspected the digs, some of them conducting their own tests.

At the end of dig season this year, Dr. Goodyear seemed reconciled to the prospect of hard years of excavation, research and argument ahead.

"If this is 25,000 years old, and I think it is, then scientists will come here from all over the world to see for themselves," he said, while driving back to Barnwell after a day in the field. "And they will argue about it for another 10 years."

The challenge for the Topper archaeologists, as for others making pre-Clovis discoveries, is not only the ambiguity of the evidence, but also its unfamiliarity. Clovis workmanship was painstaking and distinctive. Nearly all the spear points were several inches long and sharpened on both sides. Many of them were found among bones of mammoths that they were used to kill, accounting for the long-held reputation of the Clovis people as primarily big-game hunters. That also agrees with the theory that the first Americans crossed from Siberia to Alaska in pursuit of mammoth and mastodon at the end of the last Ice Age.

Yet all claims for pre-Clovis cultures rest largely on finds of a much more primitive technology. If these are tools, they are simpler and the weapon points are not bifacial; they are finished on only one side. For these and other reasons, archaeologists who made their careers on the Clovis culture usually react to possible evidence of predecessors with stiff skepticism.

Calling this the "Clovis bias," Dr. Goodyear said, "You look for something with one idea in mind, and you don't see it, then people become uncomfortable and confused, and they often reject it."

That is changing, though. Three other likely pre-Clovis sites have been found in the eastern United States: at Meadowcroft, Pa., near Pittsburgh, and at Cactus Hill and Saltville in Virginia. Other sites in South America, besides Monte Verde, may precede the Clovis period.

Bluefish Caves, in the Yukon, is still disputed as a focus of pre-Clovis research.

Signs of pre-Clovis people are sparse because these mobile bands were few in number and trod lightly on the land, and also because archaeologists had until recently not been looking deeply enough.

"For generations, we assumed that Clovis was the primordial human culture south of the ice sheets, but that model has long been discredited," Dr. Brian M. Fagan, an archaeologist at the University of California, Santa Barbara, wrote in an updated edition of "The Long Journey: The Peopling of America," published this year by the University Press of Florida.

"We simply do not know when the first human settlers moved south of the ice sheets," Dr. Fagan concluded, noting that the archaeological record now showed the migration to be "an untidy process of rapid colonization, by people acquiring foods in many ways, who used a broad range of stone and wooden artifacts and, also occasionally, bone tools to survive."

It makes sense to Dr. Goodyear and his associates at the South Carolina Institute of Archaeology and Anthropology in Columbia that long before Clovis, bands of people moving up the Savannah River from the coast spotted chert washing out of the hillside. It still does. The dirt road at the Topper site is sprinkled with the rock. The hunter-gatherers quarried the chert, made their tools as best they could and then went on their way, to return again and again.

And so will Dr. Goodyear and probably many more archaeologists in search of the earliest people to live in the Americas.