Fuente: REALscience
Expuesto el: miércoles, 18 de julio de 2012 18:19
Autor: Michael Bradbury
Asunto: New Culture Predates Clovis in America
| Technology is an easy way to distinguish between cultures. Even among ancient peoples their technology set them apart from their contemporaries. Now, new research from Oregon shows once an for all that a culture lived in what is now the western U.S. before or at least at the same time as the Clovis people of New Mexico.
Western Stem Arrowheads Found in Paisley Caves in Oregon Since the 1970s archaeologists have been arguing over who settled America first. Now using DNA evidence and spear fragments from the Paisley Caves, University of Oregon archeologist Dennis Jenkins says the Clovis style of chipping stones is not the mother of Stone Age technology. What is known as the Western Stem weapons include flint arrowheads and spear points used as tools. The Western Stem weapons are shaped differently from Clovis projectiles and represent a completely divergent technology. For decades the debate raged over Clovis v. Western Stem and which stone tool culture came first. Jenkins and his team found signs of an earlier culture four years ago have been studying this important archeological claim. Now he is confident the two styles of stone tools developed independently 13,200 years ago by the two different groups that took different routes across the continent after crossing and Ice Age land bridge from Asia. The findings appear in the journal Science this week. Jenkins and his team say the first Oregonians came from Siberia or eastern Asia. The new findings will not sit well with the “Clovis First” group of archeologists who believe the Clovis people were the first inhabitants of North America, migrating over the Bering Strait Bridge 13,500 years ago. Defenders of the “Clovis First” theory claimed that Jenkins’ 2008 findings were based on contaminated samples. So Jenkins and his team returned to the Paisley Caves in south-central Oregon to collect more evidence that another culture predated the Clovis people in America. Using new dating techniques the researchers confirmed their data using precision carbon dating.
University of Oregon Archaeologist Dennis Jenkins Holding 13,200-year-old Coprolite The team discovered fossilized human feces in sediment layers about seven feet down. The feces, known as coprolites, were all collected under very controlled conditions. Eske Willerslev from the University of Copenhagen in Denmark and a member of Jenkins’ team says, “When they were discovered in the sediments, people with full body suits, face masks and gloves took the coprolites out and put them into a sterile container.” The samples then went to independent labs to establish their status – their age and DNA content. Besides confirming the age of the coprolites, the team also made a startling discovery. In addition to petrified poop they discovered Western Stem tools. Arrowheads dated back more than 14,000 years, well before the Clovis arrived in North America. Discovering Western Stem technology in Oregon answers the decades-old question of who settled America first. Jenkins says, “Are Western Stem points as old as Clovis? That has been debated since the 1970’s, certainly, and people propose that we have established that fact beyond question.” Most archeologists believe that Western Stem technology developed from Clovis technology. This new research shows that Western Stem was at least current if not a precursor to the Clovis settlement. The Western Stem tools Jenkins and his team found dated back to 13,200 years ago, the same time as the Clovis culture. But the coprolites dated back to 14,500 years ago, well before the Clovis people. The discovery at Paisley Caves further undermines the “Clovis First” theory which had been losing ground anyway. In recent years there is more and more evidence that placed people in North America 15,000-16,000 years ago, well before sea levels dropped about 13,500 years ago, exposing a land bridge that connected Asia to North America across what is now the Bering Strait. Based on the DNA evidence found in the caves Dr. Willerslev says, “The haplogroups, or the DNA types, are similar to what you find among certain Asian groups, also among [modern] Native American groups. So, in terms of the mother line, this definitely suggests that [the Paisley Cave] people are Asians in origin and possibly – it’s not 100% certain – could be ancestral to Native Americans.”
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