Wednesday, April 30, 2008

You Are What You Eat? Maybe Not for Ancient Man

Careful analysis of microscopic abrasions on the teeth of early human "cousins" by resesarchers at Johns Hopkins, University of Arkansas, Cambridge University and Stony Brook University show that although equipped with thick enamel, large jaws and powerful chewing muscles, this ancient species may not have eaten the nuts, seeds or roots their anatomy suggests. Instead, the tooth wear suggests a more general diet, as reported in next week's Public Library of Science One.

"For so many years we've operated under the assumption that the shape of something's teeth, jaws and skull tells us what they habitually ate," says Mark Teaford, Ph.D., a professor of anatomy at Hopkins' Center for Functional Anatomy and Evolution. "But it seems like we had the wrong idea - just because they're capable of eating hard foods doesn't mean that they did - it really makes us rethink some of our basic assumptions."

Using high-powered microscopy to scan tooth surfaces and computer programs that measure imperfections on the surfaces of teeth, the researchers analyzed tooth surfaces from Paranthropus boisei from eastern Africa. According to most researchers, P. boisei's jaw and tooth structure was so specialized and extreme it must have had a very specialized diet. In fact, its anatomy gave it the nickname "Nutcracker Man."

Measuring the microwear from permanent molars of P. boisei from Ethiopia, Kenya and Tanzania dating from 2.27 million years ago to about 1.4 million years ago, the team compared their results with microwear from living primates and other fossils. They found that P. boisei teeth had very little pitting indicative of eating hard foods.

"It seems that while they were perhaps capable of eating harder foods, they generally didn't," says Teaford. "We see similar situations in modern primates, who often like soft fruit. But they can't find that all the time, so occasionally they'll eat harder or tougher foods if they have to."

"Looking at P. boisei you think 'wow, it's a chewing machine,' but that's really an oversimplification." "It may not have been so specialized," he adds.

Tuesday, April 29, 2008

Oldest arched gate in the world restored

The oldest arched gate in the world, located in Ashkelon, has been restored, nearly four thousand years after it was first built.

The Canaanite gate, which was constructed around 1,850 BCE as part of the port city's fortifications, is believed to be the most ancient arched gate in the world. The mostly brick and limestone gate is 15 meters long, more than 2 meters wide and almost 4 meters high.

Its base was uncovered in 1992 during a Harvard University archeological dig led by Prof. Lawrence Steiger, said Ra'anan Kislev, director of conservation at the Antiquities Authority.

The authority has now finished reconstructing the gate, after eight years. Three wooden arches were rebuilt to restore the complete figure of an arch and to provide support for the structure, Kislev said.

"We wanted to give visitors a feeling of walking through a gate that brings you inside a city," he said.

The $700,000 project, which was carried out with a donation from the Council for a Beautiful Israel and in cooperation with the Israel Nature and Parks Authority, is part of a long-term plan to convert the history-rich area to a more extensive archeological park, said Zeev Margalit, head of the authority's conservation and development department.

"The idea is part of a conceptual change from a park that is used for picnics and holiday barbecues and bathing to a park that is also a park of values and content," Margalit said.

Ashkelon, whose history is filled with alternating periods of construction and destruction by invaders, was a major trading center due to its location on the Coastal Road, the main thoroughfare between Egypt and Syria.

A small city shrine was also discovered outside the gate, on a slope descending toward the sea.

Inside the shrine, a bronze figurine of a calf overlayed with silver was uncovered.

The calf was a symbol of the Canaanite deity Ba'al and the shrine may have served for worship

Scholars believe the shrine was located on the way to Ashkelon's port so that those embarking on a sea voyage or returning from one could pray or give thanks to the deity for the success of their journey.

The park, which includes the city's Roman Basilica, its ancient city walls, statues of Roman and Greek goddesses, an ancient waterwheel and well, and the remains of Byzantine period church - all of them located amid lush vegetation - is open to the public throughout the week.

Ancient Sunflower Agriculture in the Americas

“People sometimes ask “What is the big deal about sunflower?” says David Lentz, professor of biological sciences and executive director of the Center for Field Studies in the McMicken College of Arts & Sciences at the University of Cincinnati (UC). Lentz worked with Mary Pohl from Florida State University, José Luis Alvarado from Mexico’s Institute of Anthropology and History, and Robert Bye from the Independent National University of Mexico.

“First of all, sunflower is one of the world's major oil seed crops and understanding its ancestry is important for modern crop-breeding purposes," Lentz says. "For a long time, we thought that sunflower was domesticated only in eastern North America, in the middle Mississippi valley — Arkansas, Missouri, Tennessee, Illinois. This is what traditional textbooks say. Now it appears that sunflower was domesticated independently in Mexico."

"The Mexican sunflower discovery suggests that there may have been some cultural exchange between eastern North America and Mesoamerica at a very early time,” Lentz adds. “Now the textbooks need to be rewritten.”

More than just a matter of pride over which part of America can claim a flower, the debate centers on when sunflower was domesticated and which civilization first cultivated it. Now there is solid evidence that two similar events took place thousands of years and hundreds of miles apart.

Lentz and his fellow researchers have documented archaeological, linguistic, ethnographic and ethnohistoric data demonstrating that the sunflower had entered the repertoire of Mexican domesticates by 2600 B.C., that its cultivation was widespread in Mexico and extended as far south as El Salvador by the first millennium B.C., that it was well known to the Aztecs, and that it is still in use by traditional Mesoamerican cultures today. (People of the Americas made huge contributions to today’s society in terms of agriculture, including the development of a number of valuable crops such as corn, peppers, beans, cotton, squash, chocolate, tomatoes and avocadoes, as well as sunflower.)
But it is unknown if the Mexican domestication and North American domestication are related. So is it coincidence? Did one cause the other? Or did they both happen because of some other common outside factor?

“Whatever conclusions we draw, the evidence clearly shows that sunflower as a Mexican crop goes back far into antiquity,” says Lentz.

In addition to the biogeographic study of sunflower, the researchers conducted archaeological, linguistic, ethnographic and ethnohistorical research, collecting data from many fields of study.

Archaeological evidence of sunflower in Mexico has been rare, probably for a number of reasons. First, the way it was used may not have been conducive to deposition in archaeological sites. Second, climatic conditions, especially in the Neotropics, have bad properties of preservation for plant parts so most things just rot away. Finally, archaeological research strategies in many areas of Mesoamerica focus more on monumental architecture and less on agricultural developments. That is, you are unlikely to find something if you are not looking for it.

Nevertheless, sunflower achenes (this is what most of us call the seed, but it is actually the fruit of the sunflower, containing the seed) were found in Mexico in situations where the preservation was especially good. Cueva del Gallo was a dry cave and the sunflower achenes there were in pristine condition. San Andrés was a waterlogged site and the sunflower remains from that site were also well preserved. Using accelerator mass spectrometry, the sunflowers at San Andrés were found to be older than 2600 B.C.

The researchers also asked indigenous people in Mexico what terms they used for the sunflower.

“They described how they used sunflower and told us the name in their native language,” says Lentz. “The names they used for sunflower were all unique, not related to Spanish. That tells us the use of sunflower is older than the Spanish expeditions of the 15th and 16th centuries."

The Otomi, one of the Mexican indigenous groups interviewed, use the name “dä nukhä,” which translates to “big flower that looks at the sun god,” a reference to pre-Columbian solar worship. The sunflower is commonly still used as an ornament in their churches.

“When asked about sunflowers, people of the Nahua culture in Mexico, descendants of the Aztecs gave us a clue to help interpret early historic texts,” describes Lentz. “The modern Nahua use two words for sunflower: ‘chimalxochitl,’ which means ‘shield flower,’ or ‘chimalacatl,’ which means ‘shield reed,’ which is also a reference to its hollow stem and large, disk-like head (that resembles an Aztec shield). These terms led us to sunflower references to listed in early chronicles of 16th century Aztec society, including ‘The Florentine Codex,’ written by Fray Bernardino de Sahagun. In the Florentine Codex, the sunflower is described as part of an offering to the Sun God, 'Huitzilopochtli.'"

The researchers point out, the sunflower’s association with solar worship and warfare in Mexico may have led to its suppression after the Spanish Conquest.

“Sunflower was believed to be a powerful aphrodisiac, which could have also contributed to its being banned by the Spanish priests,” Lentz says with a smile. “Of course, it is not but this belief was probably part of the case against sunflowers.”

“Mesoamerica had a thriving culture, a grand civilization,” Lentz notes. “They had irrigation systems, monumental construction, agriculture and a complex society.

Monday, April 7, 2008

Pre-Clovis Human DNA

Human DNA from dried excrement recovered from Oregon's Paisley Caves is the oldest found yet in the New World -- dating to 14,300 years ago, some 1,200 years before Clovis culture -- and provides apparent genetic ties to Siberia or Asia, according to an international team of 13 scientists.

Among the researchers is Dennis L. Jenkins, a senior archaeologist with the University of Oregon’s Museum of Natural and Cultural History, whose summer field expeditions over two summers uncovered a variety of artifacts in caves that had caught the scientific attention of the UO’s Luther Cressman in the 1930s.

The Paisley Caves are located in the Summer Lake basin near Paisley, about 220 miles southeast of Eugene on the eastern side of the Cascade Range. The series of eight caves are westward-facing, wave-cut shelters on the highest shoreline of pluvial Lake Chewaucan, which rose and fell in periods of greater precipitation during the Pleistocene.

The team’s extensively documented analyses on mitochondrial DNA -- genetic material passed on maternally -- removed from long-dried feces, known as coprolites, were published online April 3 in Science Express ahead of regular publication in the journal Science.

“The Paisley Cave material represents, to the best of my knowledge, the oldest human DNA obtained from the Americas,” said Eske Willerslev, director of the Centre for Ancient Genetics at Denmark’s University of Copenhagen. “Other pre-Clovis sites have been claimed, but no human DNA has been obtained, mostly because no human organic material had been recovered.”

Willerslev visited the UO in 2004 to obtain samples for DNA analyses after word spread among archaeologists and anthropologists about Jenkins’ discoveries. A Danish team, led by Willerslev, examined 14 coprolites -- initially using multiplex polymerase chain reaction to rapidly amplify DNA and a minisequencing assay – that were found by Jenkins and colleagues during summer field work in 2002 and 2003.

A lengthy analysis, including the collection of DNA samples from 55 UO students, supervisors, and site visitors and 12 Danish DNA researchers, was done to screen for modern DNA contamination. From that analysis, six coprolites containing the ancient DNA were radiocarbon dated using accelerator mass spectrometry and calendar calibrated to between 1,300 and 14,300 years ago.

“Of these, half date from the early arrival time,” Jenkins said. “All six coprolites containing ancient DNA underwent additional testing at two independent labs. Three of the six also contained DNA similar to red fox, coyote or wolf.” The researchers suggest that these early Americans ate the animals or that the animals urinated on the human feces during times of non-human habitation.

The DNA testing indicated that the feces belonged to Native Americans in haplogroups A2 and B2, haplogroups common in Siberia and east Asia.

Clovis culture began sometime between 13,200 and 12,900 years ago, according to a re-evaluation of Clovis evidence published in Science (Feb. 23, 2008) by Michael R. Waters of Texas A&M University and Thomas W. Stafford Jr. of Stafford Research Laboratories in Colorado.

Skeletal remains dating to Clovis culture have proven elusive, leaving researchers with little hard evidence beyond tell-tale cultural components such as the distinctive fluted Clovis points and other tools.

Exactly who these people living in the Oregon caves were is not known, Jenkins said. In their conclusion, the authors wrote: “The Paisley Caves lack lithic tool assemblages, thus the cultural and technological association of the early site occupants, and their relationship to the later Clovis technology are uncertain.”

"All we're doing in this paper is identifying the haplogroups," Jenkins said in an interview. "We are not saying that these people were of a particular ethnic group. At this point, we know they most likely came from Siberia or Eastern Asia, and we know something about what they were eating, which is something we can learn from coprolites. We're talking about human signature.

"If our DNA evidence and radiocarbon dating hold up on additional coprolites that are now undergoing testing at multiple labs, then we have broken the Clovis sound barrier, if you will,” he said. “If you are looking for the first people in North America, you are going to have to step back more than 1,000 years beyond Clovis to find them."

The UO's Cressman was lured to the area after being told about a woman who was digging in the caves for artifacts and began uncovering large bones, Jenkins said. Cressman, an anthropologist, died in April 1994 after 35 years on the UO faculty.

During the two summers of fieldwork, Jenkins, colleagues and students, working in four of the caves, retrieved manufactured threads of sinew and plant fibers, hide, basketry, cordage, rope, wooden pegs, animal bones, two forms of projectile point fragments and diverse kinds of feces. These items were found "in an unbroken stratigraphic sequence spanning the late Pleistocene and Holocene," the researchers wrote in the study. Some of the thread is narrower than that holding buttons on many shirts today and date back 12,750 years, Jenkins said.

"To find these threads was just incredible," said Jenkins, who directs the Northern Great Basin Archaeological Field School. "We found a little pit in the bottom of a cave. It was full of camel, horse and mountain sheep bones, and in there we found a human coprolite. We radiocarbon-dated the camel and mountain sheep bones, as well as the coprolite, to 14,300 years ago."

With radiocarbon dating adjusted to calendar years, the materials date back to about 14,400 years ago, he added. Such a dating puts the Oregon site into about the same time period as Chile's Monte Verde site.

The UO’s Cressman reported his discoveries in 1940, but his conclusions on material he found were not widely accepted because of a lack of solid documentation. “Cressman was correct about the association of human cultural remains with Pleistocene animals such as the now extinct camels, horses, and bison that once ranged the plain in front of the Paisley Caves, but it has taken nearly 70 years and the development and application of new scientific methods to prove it,” Jenkins said.

“Had the human coprolites at the Paisley Caves not been analyzed for DNA and subjected to rigorous dating methodology,” he added, "the pre-Clovis age of the artifacts recovered with the megafaunal remains could not have been conclusively proven. In other words, the pre-Clovis-aged component of this site could very well have been missed or dismissed by archaeologists.”

Thursday, April 3, 2008

Fossilized human feces reveals the first Americans

Professor Eske Willerslev was surprised by the results of the DNA tests conducted by himself and his colleagues on samples of what turned out to be fossilised human faeces found in deep caves in the Oregon desert. The oldest of the droppings have been carbon-dated to be approximately 14,340 years old. Willerslev’s faeces samples clearly contain two main genetic types of Asian origin that are unique to present-day North American Indians. Not only is this proof that the American Indians are descendants of the first immigrants to the continent, it is also proof that immigration took place approximately 1,000 years earlier than otherwise believed.

The American continent was the last of the world’s continents to be populated. There are many contradictory and more or less well-founded scientific theories on when this occurred and from where the first immigrants came. These theories span from immigration via the icy Atlantic Ocean to Thor Heyerdahl’s papyrus boat expeditions from Africa to America. The most accepted theory is based on findings of stone tools from the Clovis culture in soil layers dating back to approximately 13,000 BC. According to the theory, people from Siberia migrated, perhaps in search of mammoth, across the land bridge that once connected Siberia and North America. From there, they continued south and spread out across the American continent. The migration passed through a corridor that opened up approximately 14,000 years ago in the giant glacier that covered the American continent. But these new findings call this immigration theory into question.

“Our findings show that there were people south of the ice cap several hundred years before the ice-free corridor developed. The first humans either had to walk or sail along the American west coast to get around the ice cap,” explains Eske Willerslev, and concludes, “That is, unless they arrived so long before the last ice age that the land passage wasn’t yet blocked by ice.”

Wednesday, April 2, 2008

Assyrian ruled Israel wisely

Dr. Oded Lipschits, from Tel Aviv University’s Department of Archaeology, directs Ramat Rachel, an archaeological dig two miles from the Old City of Jerusalem. Until now archaeologists believed the site was a palace of an ancient Judean king, probably King Hezekiah, who built it around 700 BCE.

But evidence points to foreign rule, says Dr. Lipschits, who believes the site was likely an ancient local administrative center — a branch office — of Assyrian rulers. "They were wise rulers," he says, "using a good strategy for keeping control, stability and order in the region.”

As today's corporations know well, the strategy was all about location. Explains Lipschits, “Between 700 BCE to about 70 CE, Jerusalem was home to various Judean cults and at times a center for religious fanaticism. The Assyrians understood that they could gain better control of their vassal kingdom — and continue collecting taxes — by maintaining a safe distance.”

Where did they set up their branch offices? In the "suburbs." The Assyrians built their economic hub for the region two miles south of Jerusalem at Ramat Rachel. They created elaborate gardens, stocked their cellars with the wine and olive oil they collected in taxes, and quietly but carefully monitored Jerusalem.

“You can see Jerusalem from Ramat Rachel, but when you’re inside Jerusalem’s City of David, you can’t see Ramat Rachel at all,” says Lipschits. “The Assyrians kept a watchful eye, but didn’t let the locals feel a dominant foreign presence.

“It was smart for the Assyrian managers to take a few steps back, and not appear to be interfering with the city’s religious center and local culture. Businesses today could be advised to adopt similar strategies with their branch offices in foreign locations,” he surmises.

Lipschits is currently writing a book about this precursor to today's corporate strategies with Boston College’s Prof. David S. Vanderhooft. He is also the author of the popular book The Fall and Rise of Jerusalem (Eisenbrauns 2005).

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For more about Ramat Rachel, please visit: http://www.tau.ac.il/~rmtrachl/index.html.