Artifacts in Texas predate Clovis culture by 2,500 years, new study shows

This is another article about the bones discovered in Texas.

Early human toolkit debunks 'Clovis first' settlement of North America

Researchers in Texas have discovered thousands of human artifacts in a layer of earth that lies directly beneath an assemblage of Clovis relics, expanding evidence that other cultures preceded the Clovis culture in North America. This pre-Clovis toolkit appears to be between 13,200 and 15,500 years old and it includes biface and blade technology that may have later been adapted—and improved upon—by the Clovis culture.

The Clovis people, whose tools were known for their distinctive "fluted" points, were once thought to be the original settlers of North America about 13,000 years ago. Over the past few years, however, scattered evidence has hinted at several earlier cultures. But, such evidence has often been disputed in part because so few artifacts have actually been recovered.

The new site in Texas, known as the Debra L. Friedkin site, documents a pre-Clovis settlement in the region and informs researchers about the transition to Clovis culture and technology, which is later seen across North and Central America (and also into northern South America). These new artifacts comprise what researchers are calling the Buttermilk Creek Complex, and details of its excavation will be reported in the 25 March issue of Science, which is published by AAAS, the nonprofit science society.

Michael Waters from Texas A&M University and colleagues from across the United States describe the various blades, scrapers and choppers found among the 15,528 artifacts in the Buttermilk Creek Complex. They used luminescence dating, which measures the light energy trapped in sediment grains, to date the 20-centimeter thick layer of sediment surrounding the toolkit.

"At the Debra L. Friedkin site, Texas, we have found evidence of an early human occupation… 2,500 years older than Clovis," said Dr. Waters. "This makes the Friedkin site the oldest credible archaeological site in Texas and North America. The site is important to the debate about the timing of the colonization of the Americas and the origins of Clovis."

The newly discovered tools are small and made of chert, and the researchers suggest that they were designed for a mobile toolkit—something that could be easily packed up and moved to a new location. These tools are recognizably different from Clovis tools although they do share some similarities, including the use of biface and bladelet technology.

In the past, researchers have argued that the Clovis people were the oldest human inhabitants of the Americas. This "Clovis First" model theorizes that the Clovis people came to the New World from Northeast Asia by crossing the Bering Land Bridge, which once connected Asia and North America. From there, it suggests that they spread out across the continent and eventually made their way down to South America.

However, some problems with this model have recently arisen. First of all, no Clovis technology has been found in Northeast Asia and the fluted points that have been discovered in Alaska are all too young to be Clovis. (They were also made a bit differently than Clovis points.) Furthermore, there are six sites in South America that do not contain Clovis technology, although they did exist during the same time period.

The Debra L. Friedkin site in Texas, implies that Clovis tools could have eventually evolved from the tools found in the Buttermilk Creek Complex—and that the Clovis culture, including the use of fluted points, likely developed in North America.

"This discovery provides ample time for Clovis to develop," said Waters. "People [from the Buttermilk Creek Complex] could have experimented with stone and invented the weapons and tools that we now recognize as Clovis… In short, it is now time to abandon once and for all the 'Clovis First' model and develop a new model for the peopling of the Americas."
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References:

EurekAlert. 2011. "Artifacts in Texas predate Clovis culture by 2,500 years, new study shows". EurekAlert. Posted: March 24, 2011. Available online: http://www.eurekalert.org/pub_releases/2011-03/aaft-ait031811.php

Paleo-Indians settled North America earlier than thought, study suggests

Researchers excavating a creek bed in central Texas have found evidence suggesting humans settled in North America some two thousand years earlier than previously estimated.

The findings are reported in the March 25 issue of Science.

Earth scientists at the University of Illinois at Chicago determined the age using an optical dating technique. They linked sediment and mineral samples to human artifacts and tools found in a single stratigraphic layer located below younger, previously dated Paleo-Indian Clovis-culture artifacts.

Texas A&M University anthropologist Michael Waters led the archaeological dig in the Buttermilk Creek complex, near Austin, which has been excavated for years. While artifacts suggesting earlier settlement had been found at the site before, they couldn't be verifiably dated.

UIC earth and environmental sciences professor Steven Forman worked with Waters and a multi-university team of researchers, finding buried beneath the Clovis layer tools such as blades and cores -- technologies unique to the Clovis culture.

Forman gathered about 50 core samples from two sites at Buttermilk Creek for luminescence dating analysis at UIC. Carbon-14 dating couldn't be used to date the pre-Clovis artifact layer because that layer didn't contain any organic matter.

"We dated the sediments by a variety of optical methods," Forman said. "We also dated different mineral fractions as well, and we consistently got the same ages. We looked at the age structure of the sediment by many different ways and got the same answers."

This is the first time that optical dating has been used to constrain a paleoculture within a date range, Forman said.

Luminescence dating, a relatively new technique, measures light energy trapped in minerals such as feldspar and quartz formed centuries ago. Samples must be carefully handled to avoid any exposure to light, which would contaminate the readings. They were analyzed in a darkroom laboratory at UIC.

"We found Buttermilk Creek to be about 15,500 years ago -- a few thousand years before Clovis," Forman said. "It's the first identification of pre-Clovis lithic technology (stone tool technology) in North America."
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References:

EurekAlert. 2011. "Paleo-Indians settled North America earlier than thought, study suggests". EurekAlert. Posted: March 24, 2011. Available online: http://www.eurekalert.org/pub_releases/2011-03/uoia-psn031711.php

Basketry from Peru's Huaca Prieta

A collection of plant fiber artifacts woven by inhabitants of Huaca Prieta, a pre-Columbian site of the Late Preceramic Period in northern Peru, is making its way to the laboratory of Dr. James Adovasio, director of the Mercyhurst Archaeological Institute.

One of the world's leading authorities in the analysis of basketry, textiles, cordage and other plant fiber-derived artifacts in prehistoric societies, Adovasio recently returned from a two-week excursion in Peru, where he analyzed basketry from recent excavations at Huaca Prieta conducted by Vanderbilt University archaeologist Dr. Tom Dillehay.

Archaeological excavations at Huaca Prieta have revealed a complex mound built in several stages from about 7000 to 4800 years ago. This impressive structure is replete with a massive access ramp and numerous burials. The site is thought to represent one of the earliest examples of emerging cultural complexity in South America.

Adovasio, author of the just republished "Basketry Technology: A Guide to Identification and Analysis," said his analysis of the Huaca Prieta artifacts will continue at Mercyhurst in the R. L. Andrews Center for Perishables Analysis. Co-founded by Adovasio and his late wife, R.L. Andrews, the newly renovated lab provides an unprecedented research opportunity for the college's archaeology faculty, undergraduate and graduate students. It will be officially dedicated May 5.

"Mercyhurst's perishable artifact analysis lab is the only lab of this kind in the hemisphere," Adovasio said. "Perishables analysis is a small and relatively arcane specialization. Typically what we have learned about prehistoric civilizations comes from the study of durable materials, like stone and ceramics, when, in fact, 95 percent of what people manufactured prehistorically was made out of perishable materials."

Adovasio will be one of a handful of archaeologists from North America to share his expertise at the "Basketry and Beyond: Constructing Cultures" conference at the University of East Anglia in Norwich, England, April 14-16. He will deliver the keynote address: "Style, Basketry and Basketmakers Redux: Looking at Individuals through a Perishable Prism."

Two weeks later, Adovasio and Mercyhurst faculty Dr. Ed Jolie, who currently directs the R.L. Andrews lab, will travel to Sante Fe, N.M., to present at a School for Advanced Research (SAR) seminar on "Fiber Perishable Chronologies in the Great Basin of Western North America."

Funded by the National Science Foundation, the seminar unites scientists from both universities and museums with research interests in the prehistory of the Great Basin and dating fiber perishable artifacts in order to better establish regional cultural chronologies. The April 26-28 seminar will enable the group to assess their data, consider future investigations and move toward publication.
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References:

Science Daily. 2011. "Basketry from Peru's Huaca Prieta". Science Daily. Posted: March 23, 2011. Available online: ttp://www.sciencedaily.com/releases/2011/03/110323145753.htm

Ancient trash heaps gave rise to Everglades tree islands

Garbage mounds left by prehistoric humans might have driven the formation of many of the Florida Everglades' tree islands, distinctive havens of exceptional ecological richness in the sprawling marsh that are today threatened by human development.

Tree islands are patches of relatively high and dry ground that dot the marshes of the Everglades. Typically a meter (3.3 feet) or so high, many of them are elevated enough to allow trees to grow. They provide a nesting site for alligators and a refuge for birds, panthers, and other wildlife.

Scientists have thought for many years that the so-called fixed tree islands (a larger type of tree island frequently found in the Everglades' main channel, Shark River Slough) developed on protrusions from the rocky layer of a mineral called carbonate that sits beneath the marsh. Now, new research indicates that the real trigger for island development might have been middens, or trash piles left behind from human settlements that date to about 5,000 years ago.

These middens, a mixture of bones, food discards, charcoal, and human artifacts (such as clay pots and shell tools), would have provided an elevated area, drier than the surrounding marsh, allowing trees and other vegetation to grow. Bones also leaked phosphorus, a nutrient for plants that is otherwise scarce in the Everglades.

"This goes to show that human disturbance in the environment doesn't always have a negative consequence," says Gail Chmura, a paleoecologist at McGill University in Montreal, Canada, and one of the authors of the study.

Chmura will be presenting her research tomorrow, Tuesday 22 March, at the American Geophysical Union's Chapman Conference on Climates, Past Landscapes, and Civilizations. About 95 scientists have converged on Santa Fe this week to discuss the latest research findings from archeology, paleoclimatology, paleoecology, and other fields that reveal how changes in regional and global climate have impacted the development and fates of societies.

In a previous scientific investigation of tree islands, Margo Schwadron, an archeologist with the National Park Service, cut through the elevated bedrock at the base of two islands and discovered that it was actually a so-called "perched carbonate layer," because there was more soil and a midden below. Later, a team including Chmura's graduate student Maria-Theresia Graf performed additional excavations in South Florida and found more of the perched carbonate layers.

Chemical analysis of samples of these curious perched layers revealed that they are made up partially of carbonates that had dissolved from the bedrock below, Chmura says. The layer also contains phosphorus from dissolved bones, she adds. Her team concluded that trees are key to the formation of this layer: During South Florida's dry season, their roots draw in large quantities of ground water but allow the phosphates and carbonates dissolved in it to seep out and coalesce into the stone-like layer.

The perched carbonate plays a key role in letting tree islands rebound after fires: because it does not burn, it protects the underlying soil, and it maintains the islands' elevation, allowing vegetation to regrow after the fire. Humans are now threatening the existence of tree islands, by cutting down trees (whose roots keep the perched layer in place) and artificially maintaining high water levels year-round in some water control systems, which could cause the layer to dissolve.

Chmura's team now wants to explore exactly when trees started growing on the tree islands.
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References:

EurekAlert. 2011. "Ancient trash heaps gave rise to Everglades tree islands". EurekAlert. Posted: March 21, 2011. Available online: http://www.eurekalert.org/pub_releases/2011-03/agu-ath032111.php

Sign language users read words and see signs simultaneously

People fluent in sign language may simultaneously keep words and signs in their minds as they read, according to an international team of researchers.

In an experiment, deaf readers were quicker and more accurate in determining the meaningful relationship between English word pairs when the word pairs were matched with similar signs, according to Judith Kroll, Distinguished Professor of Psychology, Linguistics and Women's Studies, Penn State. The slightly better reaction time and improved accuracy rate indicates that the readers are able to juggle both English and sign language at the same time.

"If a sign language user is a bilingual juggler they might not respond to the connections between the signs and words in a conscious way," said Kroll, who serves as the director of Penn State's Center for Language Science. "But we can design experiments to measure the unconscious response."

The study shows that sign language users are similar to other bilinguals, said Kroll, who also worked with Jill Morford, professor, University of New Mexico; Erin Wilkinson, assistant professor, University of Manitoba; Agnes Villwock, student, University of Hamburg; and Pilar Pinar, associate professor, Gallaudet University.

"This reflects previous research on bilinguals that shows both languages are active even when they're reading or speaking one language," Kroll said.

According to Morford, who was the lead author for the study, the research also represents the growing acceptance among the scientific community that sign language is a real language.

"This work is critical to help make the science of studying American Sign Language every bit as rigorous as the study of other languages," said Morford.

The researchers, who released their findings in a recent issue of Cognition, tested 19 deaf adults who were fluent in American Sign Language as they decided whether pairs of English words were related or unrelated in meaning.

A total of 120 word pairs was divided into two groups of 60 word pairs that had either related or unrelated meanings. Of the related pairs, such as bird-duck, 14 also had similar signs while 16 of the unrelated word pairs had similar signs. In ASL, signs are considered related if they have similar hand shapes, locations, movements or orientations. The researchers added a number of randomly assigned word pairs to complete the test.

When the participants encountered word pairs and signs that were related, the reaction time was significantly faster and more accurate than the reaction of a control group made up of 15 bilingual speakers who spoke English as a second language.

When the word pairs were matched with unrelated signs, the participants' reaction time was slower and less accurate.

"You see interference," said Kroll. "The reaction isn't slowed down enough to cause issues in the day-to-day usage of the language, but there's a momentary gap in processing that indicates that the bilingual is not processing information like monolinguals."
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References:

EurekAlert. 2011. "Sign language users read words and see signs simultaneously". EurekAlert. Posted: March 22, 2011l Available online: http://www.eurekalert.org/pub_releases/2011-03/ps-slu032211.php

Study shows Native Americans modified American landscape years prior to arrival of Europeans

Study has important implications to how "sensitive" landscapes are to land-use and farming strategies

A new study by Baylor University geology researchers shows that Native Americans' land use nearly a century ago produced a widespread impact on the eastern North American landscape and floodplain development several hundred years prior to the arrival of major European settlements.

The study appears on-line in the journal Geology.

Researchers attribute early colonial land-use practices, such as deforestation, plowing and damming with influencing present-day hydrological systems across eastern North America. Previous studies suggest that Native Americans' land use in eastern North America initially caused the change in hydrological systems, however, little direct evidence has been provided until now.

The Baylor study found that pre-European so-called "natural" floodplains have a history of prehistoric indigenous land use, and thus colonial-era Europeans were not the first people to have an impact on the hydrologic systems of eastern North America. The study also found that prehistoric small-scale agricultural societies caused widespread ecological change and increased sedimentation in hydrologic systems during the Medieval Climate Anomaly–Little Ice Age, which occurred about 700 to 1,000 years ago.

"These are two very important findings," said Gary Stinchcomb, a Baylor doctoral candidate who conducted the study. "The findings conclusively demonstrate that Native Americans in eastern North America impacted their environment well before the arrival of Europeans. Through their agricultural practices, Native Americans increased soil erosion and sediment yields to the Delaware River basin."

The Baylor researchers found that prehistoric people decreased forest cover to reorient their settlements and intensify corn production. They also contributed to increased sedimentation in valley bottoms about 700 to 1,000 years ago, much earlier than previously thought. The findings suggest that prehistoric land use was the initial cause of increased sedimentation in the valley bottoms, and sedimentation was later amplified by wetter and stormier conditions.

To conduct the study, the Baylor researchers took samples from several different spots along the Delaware River Valley. Landforms were mapped based on relative elevations to Delaware River base flow and archaeological excavations assessed the presence of human habitation. The Baylor researchers then used a site-specific geoarchaeological approach and a regional synthesis of previous research to test the hypothesis that the indigenous population had a widespread impact on terrestrial sedimentation in eastern North America.

"This study provides some of the most significant evidence yet that Native Americans impacted the land to a much greater degree than previously thought," said Dr. Steve Driese, professor and chair of Baylor's department of geology, College of Arts and Sciences, who co-authored the study. "It confirms that Native American populations had widespread effects on sedimentation."

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References:

EurekAlert. 2011. "Study shows Native Americans modified American landscape years prior to arrival of Europeans". EurekAlert. Posted: March 21, 2011. Available online: http://www.eurekalert.org/pub_releases/2011-03/bu-ssn032111.php

Hawass Is Back as Egypt's Antiquities Minister

Some archaeologists and Egyptian activists thought Zahi Hawass was ancient history. But yesterday, according to several news reports, the controversial head of the country's antiquities has been reappointed to his post, less than a month after he threatened to resign. Hawass's resurrection came after a meeting with Egyptian Prime Minister Essam Sharaf.

The well-known archaeologist was part of the Mubarak government for many years as head of the Supreme Council of Antiquities and was named minister of antiquities in the waning days of the regime. Those ties, along with accusations of corruption and recent looting of ancient sites, have made him a controversial figure in postrevolution Egypt. But his ability to lure tourists may have trumped those concerns.

"You can lose him or you can use him," says Fredrik Hiebert, an archaeologist in Washington, D.C., with National Geographic, which has worked closely with Hawass. "He turned tourism into the number one industry for the country. You can say he's an egomaniac who doesn't let others speak, but he has put Egyptian archaeology on the front pages of newspapers around the world."

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References:

Lawler, Andrew. 2011. "Hawass Is Back as Egypt's Antiquities Minister". Science Insider. Posted: March 31, 2011. Available online: http://news.sciencemag.org/scienceinsider/2011/03/hawass-is-back-as-egypts-antiquities.html