BOSTON RHC B — BOSTON -- In a finding that could effect a revision of American prehistory, an archaeologist has uncovered strong evidence that humans lived in the New World 35,000 years ago.
The discovery in a New Mexico cave of numerous stone artifacts, hearths, butchered animal bones and a clay fragment dating back at least 35,000 years could provide proof that the Americas were inhabited long before the generally accepted date of 12,000 years ago, said Richard MacNeish, research director of the Andover, Mass., Foundation for Archaeological Research.
Sites throughout North and South America show that humans were numerous, widespread and highly skilled at hunting very soon after the last Ice Age subsided 12,000 years ago. Many of these areas have been investigated for signs that humans crossed over the Bering Sea from Asia at earlier times, although none has provided evidence strong enough to convince most archaeologists.
But the objects found by Mr. MacNeish and his team in a cave at Orogrande, N.M., have been firmly established by radiocarbon dating as 35,000 years old or older.
"The dates are exciting," said Rainer Berger, chairman of the graduate archaeology program at the University of California at Los Angeles and one of three scientists to corroborate the dates of the artifacts through radiocarbon analysis.
The discovery "will make a major impact in the direction of establishing an earlier presence of humans on this continent," he said.
Debate is likely to center on whether the material clearly indicates human presence or whether it could have arisen in other ways.
One feature that helps make the evidence from the Orogrande cave stronger than that from other sites is that its layers, deposited at different eras, have remained undisturbed, making it easier to be sure that objects found in a given layer come from the same time period.
The most solid proof of human presence earlier than 12,000 years ago may be a piece of a clay pot that appears to have a human fingerprint.
The shard was found in a layer of sediment that has been dated as being 35,000 years old. If confirmed as human, it could be the key to the findings, some archaeologists say.
Mr. Berger also points out that the cave included numerous hearths composed of rings of stones with burned material in the center. "There is no animal that makes them," he said.
In addition, the broken point of a stone spearhead embedded in a bone from a horse's foot -- apparently used as a hunting weapon -- is very similar to finds that convinced the archaeological world of a human presence 12,000 years ago.
Despite the new evidence, Mr. Berger does not think the controversy on whether humans have been in the New World longer than 12,000 years will abate. "There is always a group of people who will never accept anything," he said.