Many, if not most, Native people insist that their ancestors have lived on this continent since time immemorial, and some mainstream scientists are beginning to weigh in on their side.

Scholars are pushing evidence of human habitation in North America well beyond the non-Native accepted wisdom that places it at a relatively recent 13,000 to 14,000 years ago.

“Since Europeans came to the Americas, they have often been wrong about the Native inhabitants and Western science has not been immune to this problem,” said one Denver scientist May 29.

A perhaps-controversial 33,000 years ago, “and probably long before that,” people lived here, according to Steven R. Holen, curator of archaeology in the Denver Museum of Nature and Science’s Department of Anthropology.

“Several scientists, me included, are producing evidence of a much older Native American occupation of the continent,” he said, adding that, as has happened in the past, “the scientific establishment has underestimated the time depth of the Native American occupation of the Americas.”

A practitioner of experimental archaeology, Holen studies the patterns of breakage in mammoth bones, extrapolating and recreating the kind of instrument and force required to create such fractures and hypothesizing possible implements that could be made from the shattered remains.

“The only way these could be broken in the past as we see it is by humans using hammerstones.”

Although stone tools have not yet been found with the bones, “You don’t have to have stone tools – you have to have evidence of human technology.”

The uses of fractured bones may have varied, including that of the mammoth from Nebraska recently radiocarbon-dated at 33,000 before present (BP).

Sharp points may have been affixed to bone shafts or the bone may have been shaped into a tool to straighten shafts. Bone flakes could have been used as disposable choppers or temporary knives or other tools or utensils as needed by the continent’s inhabitants.

Holen describes the forceful impact that produces flakes from a resulting spiral fracture. A radiating line of fracture extends from the point of impact and makes it possible to determine the weight of the instrument that struck the blow, a scenario he was able to replicate in Africa on elephant bone, comparable in hardness to the bones of its mammoth relative.

Against all odds, one of only about 20 long-lived elephants in a nature preserve in Tanzania happened to die right beside the road, and the park service allowed Holen to take a single bone for testing. He fashioned a 9.5-pound instrument with a 2-inch-diameter striking head – the same size as a similar mammoth bone impact mark – and it took a younger fellow expeditionist 10 tries to fracture it.

The force required to create such impacts and the characteristics of the bones and their breakage appear to rule out such factors as damage from natural disturbance, gnawing by carnivores, or trampling by other large animals, Holen said, but he knows his findings may not be universally accepted, at least immediately, particularly in terms of the dates of human habitation they suggest.

“Scientists from several major universities, especially in western states like Nevada, Wyoming, Arizona and Alaska still ‘know’ that Native Americans have not been in North America before approximately 14,000 years ago, or just prior to Clovis culture.

“But no one has demonstrated there is a natural way the bones could be broken in these patterns. No one has yet disproved my findings.”

The 33,000-year date of the mastodon bone is “very preliminary,” he said. “We haven’t excavated yet, but it looks good at this point.” Similar fractured bones of great age have been found on the Old Crow River in the Yukon, in Europe and Siberia, and at Clovis sites.

Pushing the clock back further still, Holen said he is working on a site that is “probably much older” than the 33,000-year-old evidence he now has, but he declined to specify at this time how old the site could prove to be, or its general location.

“When I am asked the question, ‘When did people first arrive in the Americas?’ My answer now is that we do not know. I think that the term ‘from time immemorial’ may be the most accurate statement for Native American time depth in the Americas, just as many traditional Native people say.”