PRE-CLOVIS BREAKTHROUGH: Coprolites Yield Surprisingly Early Date - UPDATE

[Bianca]

                                                     Pre-Clovis Breakthrough 






April 3, 2008 
by Andrew Curry 

                                  Ancient human coprolites yield surprisingly early dates



An unlikely source of information is helping to settle one of the most contentious debates in American archaeology: Who were the first people to colonize the Americas and when did they do it?

Were they the mammoth-hunting Clovis people who lived 13,000 years ago, or some earlier group who archaeologists are just beginning to understand?

A recent discovery in the Oregon desert announced in the April 4 edition of Science may end the debate once and for all.

ARCHAEOLOGY contributing editor Andrew Curry visited Oregon's Paisley Caves in January to find out more. An excerpt of the story he filed is included here.

Look for the full report in the July/August issue of ARCHAEOLOGY magazine.--The Editors

[Bianca]

Dennis Jenkins excavating part of Paisley Caves.

Jenkins found bones, stone tools and hundreds of
coprolites--fossilized feces--at the Oregon site.

(Dennis Jenkins)

[Bianca]

On a sunny, freezing-cold afternoon in late January, I turned my rented SUV off Oregon State
Highway 31 and onto an unmarked dirt road. I was soon bumping through sagebrush and snow
across a rutted lakebed that's been dry for the last 12,000 years.

After about 20 minutes, I pulled into the shadow of a brown butte where I met Dennis Jenkins, an archaeologist from the University of Oregon.

Jenkins led me halfway up the butte over a cascade of sharp gravel to a trio of dusty caves. They
are nothing special to look at: just a few meters deep and barely tall enough to stand up in, they would have been temporary shelters at best.

Which is fine, because a few minutes would have been all someone needed to leave behind what
may be the oldest evidence of human presence in the Americas 14,300 years ago.

In a study published April 4 in the journal Science, Jenkins and University of Copenhagen geneticist Eske Willerslev argue that the artifacts were made by the ancestors of modern Native Americans,
then deliberately left behind in southern Oregon's Paisley Caves.

Which is not surprising, really, because the artifacts in question are pieces of crap.

Literally.

[Bianca]

University of Oregon archaeologist Dennis Jenkins
holds a human coprolite found at Paisley Caves.

(Andrew Curry)

[Bianca]

This unlikely story starts in 2002, when Jenkins was leading a field-school excavation of Paisley
Caves, a row of eight shallow basalt holes overlooking a prehistoric lakebed.

Six feet below the cave floor, Jenkins and his 26 students uncovered fragments of prehistoric life: camel and horse bones, sage grouse, mountain sheep and antelope bones with cut marks on them,
tiny fragments of sewing thread, a handful of what looked like stone tools and more than a dozen
oval, organic items that were exactly what they looked like: dried-up feces. (Polite archaeologists
like to call them "coprolites" when writing up excavation reports and grant applications.)

By themselves, coprolites are nothing unusual. So when Jenkins got a call from a contact at the
Bureau of Land Management saying an Oxford University graduate student was interested in experimenting on coprolites with a new DNA extraction technique, Jenkins was willing to give him
a shot--but extremely skeptical anything would come of it.

"I didn't know this guy from Adam," Jenkins says. "I'm open to new science, but not open to being labeled some kind of fringe scientist."

The grad student--Willerslev, an enthusiastic Dane known among his colleagues for his friendly personality, foul mouth and outstanding research--flew to Oregon in 2004 to take samples. "I was positively surprised. Some of the animal bones still had soft tissue on them, which indicated it was
a really good preservation environment," Willerslev says. "And I'm not a morphologist, but some of
the coprolites looked pretty human."

[Bianca]

Eske Willerslev in his University of Copenhagen lab.

Sequencing ancient DNA requires tightly controlled
conditions to prevent contamination.

[Bianca]

And that was that, for a while.

In 2005 Willerslev moved home to Denmark, where he became the youngest full professor at the University of Copenhagen thanks to his pioneering work on ancient DNA.

The Paisley coprolites sat in storage while Willerslev and his team searched for DNA at the bottom
of the Greenland ice cap and teased mammoth DNA from grains of Siberian permafrost. "The copro-
lites were lying in my freezer for quite some time," Willerslev admits. "To be honest, I didn't think
they would be that interesting."

Meanwhile, Jenkins went back to his day job as an archaeologist at the Oregon State Museum of Natural and Cultural History.

Almost two years passed, and by the summer of 2006 Jenkins had almost forgotten the whole DNA business. Then one morning he received an e-mail from Willerslev. The Dane wanted to know how
old the Paisley coprolites were.

In his lab in Copenhagen, Willerslev and a colleague had come up with stunning results. Six of the
turds contained undeniably human DNA. Not only that, they bore certain genetic markers found only
in Native American populations. Willerslev agreed to pay labs in Oxford and Florida to radiocarbon
date each coprolite.

The results, Jenkins says, were "earth-shaking."

Both labs agreed that the coprolites were left 14,300 years ago--almost 1,500 years before the earliest agreed-upon evidence for human presence in the Americas.

"For the first time, we are actually radio-carbon dating human remains that are pre-Clovis,"
Jenkins says. "There are older radiocarbon dates on sites in North America, but not directly
on human remains."

[Bianca]

The find's implications are tremendous. For almost a century, archaeologists believed that people arrived in North America 13,000 years ago--a conclusion based on dating sites with a distinctive
stone tool type first found near Clovis, New Mexico in the 1930s.

For the last two decades, the "Clovis-first" idea has been under steady assault. Call it revisionist prehistory: researchers have turned up evidence they say supports everything from a much earlier migration from Asia to a sea-borne invasion from Europe.

The coprolites Jenkins found in the Paisley caves may well be the final nail in Clovis' coffin.

While other supposed pre-Clovis sites have been bogged down in arguments over whether stone tools were made by people or by accident, there's no doubt who made the coprolites Jenkins found in the Paisley cave. "It's a much more compelling case than this odd-looking rock found next to that piece of charcoal. We know a human made this turd, whereas we don't know if that was a campfire," says Southern Methodist University archaeologist David Meltzer. "The pre-Clovis genie is sort of out of the bottle, and there's no way of stuffing it back in."



Contributing editor Andrew Curry is based in Berlin, Germany.



© 2008 by the Archaeological Institute of America

www.archaeology.org/online/features/coprolites/

[Bianca]

Here’s more information on yesterday’s announcement that 14,000-year-old human feces were discovered in a cave in Oregon.

“We finally have human remains or cells, basically molecular evidence for human beings before
the Clovis time,” said archaeologist Dennis Jenkins.

[Bianca]

Archaeologist Dennis Jenkins (center) hands up a measuring
device to Bill Cannon of the U.S. Bureau of Land Management.








                      DNA Secrets: Cave's latrines yield new evidence about prehistoric North America
 






By Jeff Barnard
THE ASSOCIATED PRESS
Published: December 4, 2008
PAISLEY, Ore.

-- For some 85 years, homesteaders, pot hunters and archaeologists have been digging at Paisley Caves, a string of shallow depressions washed out of an ancient lava flow by the waves of a lake that comes and goes with the changing climate.

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 40-mile-long lake, but is now a sagebrush desert on the northern edge of the Great Basin.

But a few years ago, Dennis Jenkins, a University of Oregon archaeologist, 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 14,300 years ago. That's 1,000 years before the oldest stone points of the Clovis culture, which for much of the 20th 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?

[Bianca]

For many years the prevailing view was that the Clovis people walked from Siberia to Alaska across a land bridge exposed by the Ice Age and spread south through an ice-free corridor down the center of the continent exposed 10,000 years ago by warming temperatures.

The Paisley coprolites indicate that 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 that some of the earliest Americans came from Europe. And they almost didn't get to tell their story.

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 that Luther Cressman, a University of Oregon archaeologist, had dug here in the 1930s, as did numerous looters.

Cannon can show you the rusty nail Cressman drove into the wall of Cave No. 2 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 that they hunted large animals. But he could make no strong conclusions, and he saved no coprolites.

Cannon could see that there was a lot that hadn't been dug, and figured that 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 the 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 shot in the high desert east of the Cascade Range. His arm carries a tattoo from a motorcycle club in 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.M., uncovered in 1929. But in three digs at Paisley -- 2002, 2003 and 2007 -- Jenkins has gathered 700 coprolites, perhaps a third of them human.

The coprolites contain pollen, seeds, chipmunk bones, sage grouse feathers, trout scales, things that ancient people would have been eating, but Jenkins couldn't be sure that they weren't coyote. He had estimated their age at 1,000 years before Clovis from dating bone and obsidian flakes found nearby.

Unlike bone, obsidian cannot be radiocarbon dated. But the time since a flake was broken off can be estimated from how far moisture has penetrated, leaving a visible band. The distance depends on temperature, so to refine the measurements, archaeological consultant Tom Origer and his team from Santa Rosa, Calif., tracked the underground temperatures for a year.

At $600 a shot, Jenkins still didn't want to get any of the coprolites radiocarbon dated until he knew they were human.

[Bianca]

Then in the fall of 2003, he received an unexpected e-mail from Alan Cooper of Oxford University, who was looking for sites to test with techniques he was developing to extract ancient DNA from soils.

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 2003, Willerslev extracted from Siberian permafrost DNA of mammoths, bison and mosses that proved to be 300,000 to 400,000 years old. More recently, he teased out DNA from silt-crusted ice cores from Greenland that showed forests, beetles and butterflies had lived 800,000 years ago where a glacier stands today.

Willerslev took home 14 coprolites, though he was not very interested.

"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. Willerslev took them with him when he took a professorship in biology at the University of Copenhagen, and in 2006 turned them over to a graduate student who needed a project. 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 14,000 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, a 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 that the caves have much more to tell. An obsidian flake and a duck bone have been dated to 16,000 years ago. And he can't wait to dig beneath some boulders that apparently fell from the roofs of the caves between 7,000 and 9,000 years ago, guarding whatever lies below from looters and other archaeologists.

When Jenkins returns, probably next spring, the diggers will be dressed like technicians in a silicon-chip plant with face masks, latex gloves and bunny suits to reduce the chances of contamination, making it possible to analyze the DNA with greater resolution. 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."



http://www2.journalnow.com/content/2008/dec/04/dna-secrets-caves-latrines-yield-new-evidence-abou/