Excavations on an army base in southeastern New Mexico have provided dramatic new evidence that humans may have lived on the North American continent for at least 36,000 years, more than three times as long as many researchers now believe, a Massachusetts researcher says.
Although other archaeologists have previously reported evidence for such early colonization of the Americas, archaeologist Richard MacNeish of the Andover Foundation for Archaeological Research said yesterday the new site -- a cave -- provides the most convincing evidence yet.
MacNeish uncovered a veritable condomimium of human history 24 floors of living quarters, complete with fireplaces, ranging from 39,000 years old on the first floor to 10,000 years old at the top. The site was dated by scientists from the University of California, Riverside, and the University of California, Los Angeles.
Among the evidence extracted from the cave is the 24,000-year-old toe bone of a horse with an arrow point embedded in it and a clay fireplace, complete with what appears to be a human thumbprint, dating from 36,000 years ago.
"This is the earliest well-documented site in America," MacNeish said. "We have found the first American Indian."
If the new date for man's arrival on the continent is correct, it means that humans would have traversed the Bering Strait from Asia under very severe climatic conditions -- when the world was in an ice age. That, in turn, suggests that early humans were an exceptionally hardy species able to cope with a broad range of adversity.
It also means that humans would have occupied North America during a period of at least 15 centuries in which sheets of ice extended over much of the continent, producing conditions grossly different than those that existed 12,000 years ago.
But the claim is likely to undergo severe criticism and intensive analysis before it is broadly accepted, other researchers said. Archaeologists are sharply divided over when North American colonization occurred, and feelings often reach a heated pitch.
"This is one of the great controversies in science," according to archaeologist Brian Fagan of the University of California, Santa Barbara. "It raises great passions and lots of people don't speak to each other."
"It's something that at least half the archaeologists in America will resist. . . ." said anthropologist Russell Barber of California State University, San Bernardino.