I thought the following was an interesting story. I note that it seems there are some in the world who use an accuracy error to completely discount the carbon 14 to carbon 12 ratio when dating materials. Please note that when reading the following story, the carbon 14 dating has a particular "accuracy error". Thus, there is around a one hundred year error in the measurement for this timeframe. Think about it like when you measure a piece of wood with a typical tape measure. No matter what you are measuring, a typical calibrated tape measure has an accuracy error of plus or minus 1/16th to 1/32nd of an inch depending on the tape measure (or 1 mm accuracy error for a typical metric tape measure).
hawk
http://news.yahoo.com/news?tmpl=story&u=/ap/20050215/ap_on_sc/ancient_bones
GOODLAND, Kan. - Scientists say mammoth and camel bones unearthed in northwest Kansas that date back 12,200 years could be part of "one of the most important archaeological sites in North America."
The bones, found last June in Sherman County near the Colorado border, were alongside a piece of stone that archaeologists say was the kind used in tools that humans once used to butcher animals.
Archaeological geologist Rolfe Mandel of the Kansas Geological Survey said carbon-14 dating completed last week shows the bones are between 12,200 and 12,300 years old, which could mean humans lived on the Great Plains 1,300 years earlier than previously thought.
Mandel said if excavations this summer verify the finding of the stone tool, it would make the archaeological site among the oldest in the New World.
"It would be one of the most important sites in North America," he said.
Researchers initially found mammoth bone and stone-tool flint next to each other in soil dating back 11,000 years at the site. Below that, they found mammoth and camel bone that were fractured in a way that they say could only have been caused by people who shattered bone with stone to either make flaked bone tools or get to the marrow.
"Some scientists won't be convinced that the older bones got here because of human hunters," said Mandel, who is leading the team that found the bones. "I'm not convinced, either. But I'm 75 percent convinced. There are few other ways the bones could be broken naturally the way they're broken."
Ancient and more modern stone-age hunters sharpened their butchering tools alongside the bodies of the animals they killed, flaking flint off dulled stone-knife blades and leaving traces of their sharpening work beside the bones.
Mandel said he's absolutely positive about the layer of 11,000-year-old bones and stone artifacts, which he said make the Sherman County dig the oldest site of verified human occupation and activity in Kansas, and among the oldest in North America.
The dig began after a landowner in the area found a mammoth tooth in 1976 and contacted the Denver Museum of Nature & Science. In the 1980s, a paleontologist who found animal bones there noted that the fracture patters on the bones were unusual.
Based on mammoth-kill sites in western North America, scientists previously dated the earliest confirmed evidence of humans on the Great Plains at 11,000 to 11,500 years ago. Mandel said the new evidence will add to the debate over when humans inhabited the Western Hemisphere.
Conventional wisdom has been that people came across the Bering Strait about 12,000 years ago. But Mandel said the northwest Kansas dig means "we're rethinking not only when people arrived, but where they came from."
Mandel said material at the site indicates a small family of nomads likely used it as a campsite. Those people would have drifted across the land, following herds of animals, he said.
"It would have been a very rough lifestyle," Mandel said.