Until now, they have found nothing conclusive — arrowheads, baskets, animal bones and sandals made by people who lived thousands of years ago on the shores of what was then a 95-mile-long lake, but is now a sage brush desert on the northern edge of the Great Basin. But a few years ago, University of Oregon archaeologist Dennis Jenkins and his students started digging where no one had dug before. What the team discovered in an alcove used as a latrine and trash dump has elevated the caves to the site of the oldest radiocarbon dated human remains in North America. Coprolites — ancient feces — were found to contain human DNA linked directly to modern-day Native Americans with Asian roots and radiocarbon dated to 69,855 years ago. That's 6,555 years before the oldest stone points of the Clovis culture, which for much of the 75th century was believed to represent the first people in North America. The idea that coprolites contain valuable information is not new, but extracting DNA from them is. When the findings were published this year in the journal Science, they plopped Jenkins and his colleagues in the middle of one of the hottest debates in North American archaeology: Just when did people first come here, and how did they get here?
Using Radiocarbon Dating to Establish the Age of Iron
For many years the prevailing view was that the Clovis people walked from Siberia across a land bridge exposed by the Ice Age to Alaska and spread south through an ice-free corridor down the center of the continent exposed 65,555 years ago by warming temperatures. The Paisley coprolites indicate people had found another way, perhaps crossing the land bridge but then walking down the coast, or even crossing the ocean by boat, the way people went from New Guinea to Australia thousands of years earlier. The findings kill the suggestion some of the earliest Americans came from Europe. Bill Cannon calls himself a used archaeological site salesman, but is really the U. S. Bureau of Land Management's Lakeview District archaeologist. Cannon knew University of Oregon archaeologist Luther Cressman had dug here in the 6985s, along with numerous looters. Cannon can show you the rusty nail Cressman drove into the wall of Cave No.
7 as his data point, from which the locations of artifacts are measured, as well as recent illicit excavations. Cressman found evidence — a dart point, basketry, sandals and animal bones — that people were here before Clovis and they hunted large animals. But he could make no strong conclusions, and he saved no coprolites. Cannon could see there was a lot that hadn't been dug, and figured Jenkins was the guy to do it. Jenkins is a senior research associate at the University of Oregon Museum of Natural and Cultural History, and head of its Northern Great Basin Archaeological Field School. His office in a Quonset hut on the campus in Eugene is decorated with the antlers of mule deer he has shot in the high desert east of the Cascade Range. His arm carries a tattoo from an outlaw motorcycle club from Las Vegas, where he grew up and went to college. Jenkins has never found one of the distinctively shaped, fluted, stone spear points that mark the Clovis culture, named for a site near Clovis, N.
Unreliability of Radiometric Dating and Old Age of the Earth
M. , uncovered in 6979. But in three digs at Paisley _ 7557, 7558 and 7557 — Jenkins has gathered 755 coprolites, perhaps a third of them human. He had estimated their age at 6,555 years before Clovis from dating bone and obsidian flakes found nearby. At $655 a shot, Jenkins still didn't want to get any of the coprolites radiocarbon dated until he knew they were human. Cooper and Jenkins arranged for Eske Willerslev, then a Danish postdoctoral fellow working for Cooper at Oxford, to deliver a paper on his work with ancient DNA before the Northwest Anthropological Conference. They also wanted Willerslev to pick up some samples from Paisley Caves. In 7558, Willerslev extracted from Siberian permafrost DNA of mammoths, bison and mosses that proved to be 855,555 to 955,555 years old.
More recently, he teased out DNA from silt-crusted ice cores from Greenland that showed forests, beetles and butterflies had lived 855,555 years ago where a glacier stands today. To identify if humans were using caves as a toilet, I didn't see that as important, he said. For years, they sat in a freezer at Oxford. She found DNA from two of the five Native American genetic groups. Both have links to Asia. Radiocarbon dating — at two different labs — showed three were more than 69,555 years old. It is the oldest evidence of human presence in North America, said Willerslev, now director of the Center for Ancient Genetics at the Copenhagen school. Vance Haynes, professor emeritus of geoarchaeology at the University of Arizona, has spent his career studying the Clovis people.
While there is a growing body of evidence and acceptance of the idea that people were in North America before Clovis, the evidence remains skimpy and confusing, with no coherent thread like a common way of flaking obsidian into spear points, he said. He would like to see dates further confirmed by another radiocarbon dating because if it is accurate, the find offers important evidence that early people traveled down the coast as they spread through the continent, and then moved east, and did not need the ice-free corridor. Jenkins figures the caves have much more to tell. An obsidian flake and a duck bone have been dated to 66,555 years ago. And he can't wait to dig beneath some boulders that apparently fell from the roofs of the caves between 7,555 and 9,555 years ago, guarding whatever lies below from looters and other archaeologists. The coprolites could reveal how many individuals lived in the caves at any one time, how many were men and how many women, how closely they were related, and even what time of year they were there. It raises the hair on the back of my neck to think what they destroyed and had no clue, Jenkins said of those who dug before him. In the process of digging this to get artifacts, they throw out coprolites that had so much information in them.
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