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The Earliest Westerners

Two significant findings by archeologists are forcing a reassessment of the date of the first migration of humans to this hemisphere.

May 02, 1996|THOMAS H. MAUGH II | TIMES STAFF WRITER

No question fires the blood of American archeologists more than the date of the first migration of humans to the Western Hemisphere.

Conservative archeologists, who want an unusually high degree of documentation for older sites, insist that the earliest thoroughly documented site for such habitation is Clovis, N.M., where evidence of Paleoindians has been firmly dated to 11,500 years ago.

More liberal scholars, in contrast, argue that the difficulties of documenting older sites does not reduce their importance. Looking at charcoal and tool fragments from a wind-swept site at Pedra Furada in northeastern Brazil or an apparent thumbprint on a clay fireplace in New Mexico, they believe that humans have occupied this hemisphere for at least 35,000 years and perhaps as many as 50,000.

Although conservatives have so far been unwilling to concede even a few hundred years beyond Clovis, new discoveries have slowly been chipping away at their position. Two new discoveries reported in April may finally break the back of that resistance.

First, archeologist Jerry McDonald of the Smithsonian Institution's Museum of Natural History reported that he had dated stone tools, charcoal and bones from a mastodon barbecue in the Saltville Valley of Virginia to 14,000 years ago, 2,500 years before Clovis.

Then archeologist Anna C. Roosevelt and her colleagues at the Field Museum in Chicago revealed the discovery of a cave in Brazil displaying remains of an 11,200-year-old culture distinctly different from the Paleoindians of Clovis and Saltville. That site contains the oldest rock art in the Americas and the oldest pottery found to date.

Taken together, the findings strongly suggest either that two groups of humans migrated into the Americas independently or that the Paleoindians who trekked across what is now the Bering Strait into Alaska did so at an early enough time that they could have evolved into two distinct cultures by the time of Clovis.

Either way, the results are forcing a reassessment of the earliest occupation of the hemisphere. The results may help to explain why North and South America took such remarkably divergent paths in cultural development.

"The situation in South America does not support the Clovis theory," Roosevelt said. "What I see is that by 11,200 [years ago] you had several regional cultures quite distinct from each other."

The new discoveries and others are "forcing us to rethink Clovis," said archeologist Thomas Dellehay of the University of Kentucky, whose own work at Monte Verde in Brazil is also pushing back the age of occupation.

The Paleoindians of Clovis were big-game hunters whose culture revolved around the animals they killed, much like the culture of the later plains Indians revolved around the buffalo. According to current theories, Paleoindians swept down from Alaska, spreading throughout the continent and into South America beginning just over 11,000 years ago.

They made characteristically fluted limestone spear points with which they slaughtered woolly mammoths, musk oxen, ground sloths, caribou, moose and bears--hunting many of them into extinction. The fluted Clovis points are the only variety that has previously been found in the Americas.

McDonald's discovery in Saltville is not, on its own, earthshaking. Two years ago, University of Florida paleontologist David Webb reported the discovery of a 12,200-year-old butchered mastodon in Florida, and others have claimed similar findings of about the same vintage on the East Coast, hinting that humans had spread throughout the north by the time of Clovis.

McDonald's find, however, not only extends the age of Paleoindians backward, but provides the most complete assemblage of artifacts of that age yet found. The mastodon was cut into pieces, the hide was missing, and the tusks were cut to specific lengths. The hard inner portions of the tusks, used by Paleoindians to make tools, were also missing.

His team also found limestone tools and rocks fractured from the heat of cooking fires. The heated rocks also showed traces of animal fat. "This is a good site with solid evidence," said paleobiologist Clayton Ray of the Smithsonian, who reviewed McDonald's data.

But Roosevelt's finding in the jungles of Brazil is potentially much more significant. Some researchers, such as archeologist Betty J. Meggers of the Smithsonian, have argued that the Amazon could not have supported primitive humans because the available foods did not provide enough starch and calories. Only the advent of slash-and-burn agriculture several thousand years later made it possible for humans to occupy the region, they say.

However, the discovery of the Caverna da Pedra Pintada (Cave of the Painted Rocks) on the north bank of the Amazon River between Manaus and Belem indicates that the jungle could have supported humans.

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