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Tools of the trade. Artist's drawing of a possible shaman burial, found near the Sea of Galilee.

Credit: P. Groszman (illustration drawn to scale)

Before there were priests or doctors, people seeking solace or treatment for an illness often called in a shaman, an intermediary between the human and spirit worlds. Archaeologists working in Israel now claim that a 12,000-year-old grave of a woman buried with various animal and human body parts is that of an early shaman. If true, it could mean that shamanism arose during a critical period in human cultural evolution.

Although largely supplanted by organized religion, shamanism is still widespread in Asia, Africa, Europe, and the Americas. For example, many Eskimo groups around the Arctic Circle practice shamanism. The roots of shamanism reach back at least to the ancient Greeks and possibly even to prehistoric times. Many archaeologists assume that shamanism preceded organized religion, and some see depictions of shamans in cave art from 15,000 years ago or earlier--although that interpretation is controversial.

But recent excavations at Hilazon Tachtit, a cave west of the Sea of Galilee in Israel, may provide new support for prehistoric shamanism. Hilazon Tachtit was occupied by the Natufians, a people who inhabited the Near East between about 15,000 and 11,500 years ago. Most archaeologists see Natufian culture as a transition between hunting and gathering and the sedentary lifestyles of early farmers. At Hilazon Tachtit, a team led by archaeologist Leore Grosman of the Hebrew University of Jerusalem has found the remains of at least 25 people, most in collective burials. But one was treated differently. A woman, about 45 years old when she died and whose pelvis and spine were deformed, was buried separately, accompanied by a menagerie of animal remains. Among her grave goods were tail bones from wild cattle, a wing bone from a golden eagle, the shells of 50 tortoises, and a large foot from another person.

The team, which reports its findings online today in the Proceedings of the National Academy of Sciences, notes that tortoises, cow tails, and eagle wings play a role in the ritualistic practices of many shamans today and that many societies ascribe special powers to physically disabled people. "It seems that the woman in the Natufian burial was perceived as being in a close relationship with these animal spirits," the authors write. They suggest that shamanism either sparked, or was the result of, the cultural upheavals that accompanied the agricultural revolution in the Near East.

"This is an extremely important report on a rare find at a critical time of cultural evolution," says Brian Hayden, an archaeologist at Simon Fraser University in Burnaby, Canada. Ian Kuijt, an anthropologist at the University of Notre Dame in South Bend, Indiana, adds that the "authors have done an excellent job of supporting their argument" for prehistoric shamanism. But Mina Evron, an archaeologist at the University of Haifa in Israel, cautions that there may be alternative explanations, though she doesn't offer one herself. Just because the team's "colorful interpretation" seems plausible, she says, "it ain't necessarily so."

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Bone to pick.
Carbon dating of ancient rat bones (like the jaw bone shown) suggests that humans first arrived in New Zealand in 1280 or later.

Credit: Janet Wilmshurst/Landcare Research

Rats caught a free ride to New Zealand when they hopped aboard the boats of early Polynesian explorers. Now, their ancient bones may help pinpoint when humans first set foot on the island. Carbon-dating of bones from the rodents indicates that people reached New Zealand around 1280 or later, rejecting previous research that suggested humans may have landed there more than 1400 years earlier.

Although most anthropologists think that humans first arrived in New Zealand around 1250 to 1300, a minority holds that people might have set foot on the island as early as 200 B.C.E. That conclusion is based on 1996 research that carbon-dated bones of rats, which are thought to have been brought to New Zealand by humans either as stowaways or for food. But this study has been controversial because there's no evidence of human settlements at that time. Some critics have suggested that the carbon dates were due to a lab error in preparing the bones.

To help clear up the confusion, a team led by Janet Wilmshurst, a paleoecologist at environmental research organization Landcare Research in Lincoln, New Zealand, used a different preparation technique that is thought to be more accurate. The researchers obtained 17 bones from the two excavation sites where the oldest rat remains had been found. Carbon-dating with the improved method indicated that the new bones were from 1280 or later. When the researchers tried the new technique on some of the bones from the previous study, all of them dated to later than 1280, indicating that the earlier research was flawed. The researchers next carbon-dated ancient seeds that the rats had gnawed and that came from one of the excavation sites. The results gave a date of 1290 or later, confirming that humans did not arrive until 1280 at the earliest, the researchers report in the 3 June issue of the Proceedings of the National Academy of Sciences.

Ian Smith, an anthropologist at the University of Otago in New Zealand, says the finding "provides convincing evidence against the assertion that either rats or people reached New Zealand prior to the 13th century A.D." He adds that the later arrival indicates that humans' devastating impact on New Zealand, which has included deforestation and the extinction of birds and marine mammals, happened in only 600 years, versus more than 2000 years if the initial bone dating had been confirmed.

David Lowe, a soil scientist at the University of Waikato in Hamilton, New Zealand, says the findings also indicate that "the destruction caused by the rats in New Zealand has been pronounced and very fast indeed." The rats wiped out several species, including some birds and frogs. Wilmshurst adds that the speed of destruction "makes the risk to currently declining populations of rat-sensitive species more pressing as they could be diminishing faster than previously assumed."

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Premodern?
The shell of this fossil turtle may predate the ancestor of modern turtles.

Credit: (fossil) Juliana Sterli/Biology Letters (turtle) Jorge A.Gonzalez (2008)

As reptiles go, turtles are old--no question. They evolved before snakes and crocodiles and preceded dinosaurs. But establishing when the common ancestor of modern turtles first appeared has recently become controversial. Now a new fossil is backing the idea that modern turtles evolved more recently than previously thought.

Living turtles are divided into two main groups--the Cryptodira and the Pleurodira--based on where on the skull the muscles that close the lower jaw are attached. In the 1970s, paleontologist Eugene Gaffney of the American Museum of Natural History (AMNH) in New York City conducted the first modern analysis of turtle evolution. He proposed that almost all fossil turtles belonged within one or the other of these two modern, or crown, groups. That meant that the common ancestor of these turtles first appeared in the Late Triassic, some 210 million years ago.

Last year, paleontologist Walter Joyce of Yale University outlined a major revision of this classification. After reviewing all of the anatomical features, called characters, of the fossil turtles, he argued in the Bulletin of the Peabody Museum of Natural History that many of the fossil taxa were so different from modern turtles that they don't belong in either the Cryptodira or the Pleurodira groups. The implication is that these two groups only evolved about 150 million years ago. "Joyce's picture of turtle evolution is totally different," says James Parham of the California Academy of Sciences, who is based in Santa Barbara.

The new fossil backs this picture, say Joyce and Parham. It comes from Argentina and was discovered in central Patagonia by a joint expedition of the Museo Paleontológico Egidio Feruglio in Trelew and AMNH. About 35 centimeters long, the fossils of a shell and skull were found in ancient lake rocks, dating to between 160 million and 146 million years old--a period in which turtle fossils are few and far between. Juliana Sterli, a Ph.D. student at the Museo de Historia Natural de San Rafael in Mendoza, Argentina, set about describing and analyzing the fossil, which has been named Condorchelys antiqua. Sterli says her research shows that Condorchelys doesn't belong to the Cryptodira or Pleurodira and fits Joyce's hypothesis that the modern groups are at least 60 million years younger than previously thought.

"It's an important fossil," Gaffney says. "A discovery like this gives an important ... glimpse of early Jurassic turtles" in South America. But Gaffney thinks that the turtle fits within his original classification scheme--as a primitive Cryptodira--and is not evidence for Joyce's reinterpretation of turtle evolution. Sterli disagrees, based on analyses of anatomical details. If Joyce and Sterli are correct, Parham notes, then modern turtles would have taken much less time to evolve.

Related site

• Overview of Gaffney's history of turtle evolution

Stone man.
The partial skull of a 500,000-year-old human (digital reconstruction shown) was found in a slab of travertine from a quarry like this one in Turkey.

Credit: John Kappelman/University of Texas, Austin

Workers at a travertine factory near Denizli, Turkey, were startled recently when they sawed a block of the limestone for tiles and discovered part of a human skull. Now, it appears they unwittingly exposed fossilized remains of a long-sought species of human that lived 500,000 years ago, researchers say. Although only four skull fragments were found, the fossil also reveals the earliest case of tuberculosis.

The Middle East has long been an important crossroads for human travelers. "It's been clear for some time that earlier hominids must have dispersed into Europe from western Asia and/or Africa, and Turkey sits squarely on the likely route," says paleoanthropologist Philip Rightmire of Harvard University, who was not a member of the team. Paleontologists have spent decades prospecting in Turkey for remains of a direct human ancestor, Homo erectus, which was the first hominid to migrate out of Africa. Although scientists have uncovered fossils of H. erectus that lived 1.7 million years ago in nearby Georgia, they have found few fossils of humans in this region that are between 1.7 million and 120,000 years old.

After the factory manager contacted a researcher at the local university, he alerted the rest of the team, which included researchers in France, Germany, and the United States. They report in the current issue of the American Journal of Physical Anthropology that the find most closely resembles H. erectus. However, Rightmire says it could also be a member of H. heidelbergensis, a species found in Europe that is thought to be the direct ancestor of Neandertals.

Regardless of its identity, lead author John Kappelman of the University of Texas, Austin, says the skull bears scars that are a "dead ringer" for those created by the Leptomeningitis tuberculosa bacterium, which causes a form of tuberculosis (TB) that attacks the brain's membranes. The scars represent the earliest signs of the disease in humans, says Kappelman. Previously, the oldest evidence of TB came from Egyptian and Peruvian mummies that were several thousand years old.

TB's presence might also provide clues about what this early human looked like and how it adapted to new habitats. If the hominid was dark-skinned, for example, it might have had trouble getting enough vitamin D as it migrated north, because dark-skinned people absorb less of the sunlight needed to make vitamin D than do light-skinned people. And when humans have vitamin D deficiency, their immune systems can be less vigilant, perhaps making dark-skinned migrants out of Africa more vulnerable to diseases such as TB as they headed to less sunny climates, says Kappelman.

"This is a hugely important discovery," says paleoanthropologist Clark Larsen of Ohio State University, Columbus, because infectious disease may reveal new challenges facing early humans as they moved into temperate regions. Kappelman hopes that the rest of the skull will be located eventually. "There was bone in the other slab we don't have," he says. "Someone may find the lottery prize of H. erectus preserved in their tile countertop."

Related sites

• More on Homo erectus
• The history of TB

Testimonial.
Ancient teeth hold clues to early hominid diets.

Credit: Science

The robust australopithecines of South Africa are often described as failed humans, having died out 1 million to 1.4 million years ago. Researchers believe their high-fiber, low-nutrient diets might have been too specialized to allow them to cope with a changing environment. A new report in tomorrow's issue of Science challenges this assumption, however, arguing that these close cousins of humans were much more culinarily adventurous than thought.

With their huge molars and massive jaw muscles, australopithecines have been portrayed as nutcrackers who crunched their way through seeds, nuts, and pulpy fruits. As Africa grew cooler and drier, however, these critical fall-back foods were hard to come by, supposedly leading to the hominid's downfall.

To test this theory, a team of American and British researchers studied the teeth of four individuals of Paranthropus robustus (also known as Australopithecus robustus) from the Swartkrans Cave in South Africa. The team scanned the teeth with a sensitive laser, which did not destroy the teeth but etched them lightly enough to free carbon gases long trapped in the enamel. Because different plants absorb atmospheric carbon dioxide differently, the researchers were able to see what types of vegetation the hominids ate based on the ratio of carbon isotopes in their teeth.

Their cuisine included a mix of tropical grasses and sedges, along with woody fruits, shrubs, and herbs, according to the findings. What's more, carbon samples from ridges laid down like tree rings in a single tooth revealed that the hominids switched between these diverse plants, depending on the time of year. The pattern held, regardless of when the hominids lived. Although the specimens date back to about 1.8 million years ago, each individual's lifetime was probably separated by thousands or tens of thousands of years, indicating that Paranthropus robustus was quite capable of dealing with changes in climate or different habitats. "We didn't expect to see as much variability as we found," says lead author Matt Sponheimer of University of Colorado at Boulder. "It was quite a surprise."

The new method is a huge improvement over old isotopic studies that required anthropologists to drill--and destroy--teeth to sample carbon, like prehistoric dentists, says paleoanthropologist Fred Grine of the Stony Brook University in New York. "Sponheimer's taken the analysis of carbon isotopes in fossils to a new level of sophistication," he says, adding that he hopes that fossil teeth--and diets--of earlier hominids can also be studied with the new nondestructive method.

Related sites

• For more on Paranthropus robustus
• For more on isotopic analysis to reconstruct diet

You're welcome.
Neandertals may have given humans a valuable brain gene.

Credit: Philippe Plailly/EURELIOS, Reconstruction Atelier Daynes

For decades, human evolution researchers have debated whether Neandertals and modern humans interbred. Most scientists have come down on the side that any romances between these hominid cousins must have been fleeting at best. But a new study suggests that a few of these passing dalliances might have had a major impact on the evolution of the Homo sapiens brain. If so, Neandertals, although long extinct, may have left humanity a lasting genetic gift.

Some anthropologists have argued that a handful of hominid skeletons show features of both Neandertals and modern humans (Science, 11 February 2005, p. 841). But so far sequencing of Neandertal ancient DNA has turned up no signs of such interbreeding (Science, 11 July 1997, p. 176). As a result, most researchers have considered the two species genetically separate.

Now, University of Chicago geneticist Bruce Lahn and his colleagues report evidence that at least one gene might have bridged the evolutionary divide. Lahn's team analyzed the origins of the gene microcephalin, thought to be involved in regulating brain growth. Last year, the team reported in Science that a particular variant of the gene, now present in 70% of the world's population, arose about 37,000 years ago and quickly spread around the globe. Apparently the variant, known as haplogroup D, was favored by natural selection, although no one is sure of its function (Science, 9 September 2005, p. 1662).

In the new study, published online this week in the Proceedings of the National Academy of Sciences, Lahn and coworkers analyzed microcephalin genes from 89 people from around the world. They found that haplogroup D differed in so many bases from other versions of microcephalin that it must have arisen very early, probably a little more than 1 million years ago, according to statistical tests. Yet it appeared in modern humans only 37,000 years ago.

The Lahn group concluded that the most likely scenario was interbreeding between prehistoric modern humans and a now extinct hominid that carried haplogroup D--most likely Neandertals. The haplogroup was probably beneficial enough to spread quickly in modern human populations, says Lahn. But he's not sure what advantage it offered. Because most researchers agree that Neandertals were not as cognitively advanced as modern humans, Lahn and his coauthors suggest that the haplogroup might have made Homo sapiens better able to adapt to the Eurasian environments that Neandertals had occupied long before modern newcomers arrived.

Ancient DNA pioneer Svante Pääbo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, says that this new work is "the most compelling case to date for a genetic contribution of Neandertals to modern humans." Indeed, Pääbo says, he will now search for the haplogroup D variant of microcephalin in his own studies of the Neandertal genome.

Related sites

• ScienceNOW on interbreeding between humans and Neandertals
• Background on Neandertal DNA from the Smithsonian
• Mitochondrial DNA from Neandertals

When New York University (NYU) officials announced last week the creation of the Institute for the Study of the Ancient World, it was widely seen as a major coup. The new Ph.D.-granting research institute, devoted to the art, archaeology, history, literature, and geography of ancient societies, was made possible by a private gift of $200 million in cash and real estate, one of the largest donations the university has ever landed. Yet some NYU faculty, along with outside archaeologists, are aghast that the school accepted the money. One leading NYU archaeologist has already resigned from the university's existing ancient studies center to protest the decision.

The fracas stems from the source of the new institute's funds: The Leon Levy Foundation, named after the late Wall Street investor and philanthropist. Levy and his widow Shelby White, the foundation's trustee, have for years been at the center of controversies surrounding their antiquities collection, which some archaeologists believe includes objects that had been looted and illicitly traded. Indeed, several institutions, including Bryn Mawr College in Pennsylvania and the University of Cincinnati in Ohio, have adopted explicit policies against accepting funds from the foundation. "I wouldn't touch a gift from Shelby White with a barge pole," says archaeologist Colin Renfrew of Cambridge University in the United Kingdom.

But other scholars argue that the Levy Foundation has been a positive force, spending millions for archaeological digs (Science, 2 July 1999, p. 36). The foundation also funds a program based at Harvard University that supports the publication of archaeological findings. "The foundation has done a power of good," says Baruch Halpern, an expert in ancient history at Pennsylvania State University in State College. And Christopher Ratté, a classical archaeologist at NYU, whose publications have received Levy-White support, says that "it is very difficult to argue with this kind of generosity."

White herself takes strong issue with the criticisms leveled by some archaeologists. "We have always collected in good faith, and we have always exhibited our collection publicly," she told Science, referring to herself and her late husband. White adds that the items in the collection were not purchased in "obscure places" but at public auctions and from leading dealers. "If it turns out that there are objects that I should not have bought, then I will deal with them."

Some NYU faculty began questioning the wisdom of accepting the donation in January, when the advisory committee of NYU's existing Center for Ancient Studies was asked to review the proposed Levy donation. "We wanted to be sure that NYU administrators were aware of concerns in the archaeological community about the problem of safeguarding cultural property," says Laura Slatkin, an NYU classicist and advisory committee member. Still, center director Matthew Santirocco says there was a "majority consensus" in favor of accepting the donation among committee members. The funds are a "truly transformative gift," he says, that will "lead to a more holistic understanding of the ancient world."

Those benefits weren't enough to sway archaeologist Randall White. In a letter delivered to Santirocco last Friday, White resigned his membership in the school's ancient studies center, arguing that accepting money from the Levy Foundation could have negative consequences for NYU scholars. "The gift will promote suspicion that objects would be ripped from their archaeological context by looters," he says.

Most opponents of the donation assume, however, that the institute will go ahead. Says NYU archaeologist and center member Rita Wright: "It remains to be seen whether this donation, and the institute it will create, will be in the best interests of research into ancient cultures."

Related site

• Center for Ancient Studies at NYU