Researcher uncovers surprising cause of the demise of Easter Island indigenous population

Easter Island Credit: Yale

A new paper by a team of researchers including a Virginia Commonwealth University anthropology professor sheds new light on what led to the downfall of the indigenous population of Easter Island — also known as Rapa Nui — prior to European contact in 1722.

The study, "Variation in Rapa Nui (Easter Island) Land Use Indicates Production and Population Peaks Prior to European Contact," published in the Proceedings of the National Academy of Sciences, found that the population's demise likely had more to do with pre-existing environmental conditions than with environmental degradation by the indigenous people.

Christopher Stevenson, Ph.D., an assistant professor of anthropology in the School of World Studies in the College of Humanities and Sciences, recently discussed his team's findings with VCU News.

Your paper explores what led to the collapse of the prehistoric population of Rapa Nui. What did you conclude?

Our paper evaluates a longstanding debate and examines whether the prehistoric population of Rapa Nui experienced a significant islandwide demographic collapse prior to European contact in A.D. 1722. We have used dates from hydrated obsidian artifacts recovered from habitation sites as a proxy for land use over time. The analysis suggests region-specific dynamics that include abandonment of western coast and interior locations. These temporal land-use patterns correlate with rainfall variation and soil quality. The environmental stresses are regionally specific rather than islandwide. Significant erosion around the entire island generated by deforestation has been hypothesized by other researchers as a cause for economic failure. This does not hold up to scrutiny.

How would you characterize the significance of your findings?

This analysis demonstrates that the concept of a sudden "collapse" is a misleading characterization of prehistoric human population dynamics. As a result, we see our approach as useful in the study of other prehistoric societies for which a very rapid demographic collapse has been proposed in prehistory.

Although small, islands can be complex ecosystems that are structured by climatic variation and underlying geology. Human activities are constrained by these parameters and can even cause the ecosystem conditions to change appreciably through their manipulation of the landscape.

Were you surprised by what you found? In what ways?

The results of our research were really quite surprising to our team. Indeed, in the past we’ve published articles about how there was little evidence for pre-European contact societal collapse. When we proposed the [National Science Foundation-funded] project we were expecting that we would gather data supporting the notion that change did not occur until after European contact. In contrast our research suggests that significant changes in land use occurred prior to European contact. The connection between those changes in land use and notions of environmental degradation and subsequent societal collapse are limited.

There is no evidence that massive physical erosion took place on Rapa Nui before European contact and it is unlikely that physical erosion caused productivity decline and societal collapse. While we do not have direct population data, it is clear that people were reacting to regional environmental variation on the island before they were devastated by the introduction of European diseases and other historic processes. In short, our research does not support the suggestion that societal collapse occurred prior to European contact due to physical erosion and productivity decline, but it does indicate that use of less optimal environmental regions changed prior to European contact.

What did your research methodology entail?

We used a method called obsidian hydration dating to date the human creation of volcanic glass tools found at habitation sites. These dates were a proxy for the relative number of people on the island throughout prehistory. We also used an analysis of soil nutrients to look at the fertility of various landforms (e.g., coastal vs. upland) at different elevations up to 500 meters above sea level.

You've written several books on Rapa Nui. What led to your interest in this topic?

This is a continuation of my interest in looking at the development of agricultural systems in small island societies and how that impacts social and economic decisions made in prehistory.

What will you be working on next?

We will be applying some of the same concepts to the Canary Island agricultural systems which have a much higher diversity of geological ages and climatic conditions.

Source: Vcu

Viking fortress discovery: Archaeological dating results

Two carbon-14 dating results have removed all doubt regarding the authenticity of the Viking fortress.
Credit: Image courtesy of Aarhus University

In September 2014, archaeologists from the Danish Castle Centre and Aarhus University announced the discovery of a Viking fortress in a field belonging to Vallø Manor, located west of Køge on the east coast of Sealand. This was the first discovery of its kind in Denmark in over 60 years. Since then, archaeologists have been waiting impatiently for the results of the dating of the fortress. Now the first results are available, and they will be presented at a seminar at Aarhus University on 18 November.

"When the discovery was published back in September, we were certain that we had found a Viking ring fortress, but since then there have been intense discussions online and amongst archaeologists about whether we were right. Now we know without doubt that we have found a fortress from the 10th century," says archaeologist Nanna Holm, curator of the Danish Castle Centre.

Two carbon-14 dating results have removed all doubt regarding the authenticity of the Viking fortress. The carbon-14 dating was performed by the AMS 14C Dating Centre at the Department of Physics and Astronomy at Aarhus University in close collaboration with Accium BioSciences' laboratories in Seattle.

"The two samples were both taken from the outermost tree rings of charred logs that were found in the northern gateway of the fortress. The results of the two samples are almost identical: The fortress was built in the period between the year 900 and the beginning of the 11th century," explains Marie Kanstrup, an employee at the AMS 14C Dating Centre at the Department of Physics and Astronomy, Aarhus University.

Dating is important in determining the role of the fortress in the history of the Viking age

Søren Sindbæk, a professor of medieval archaeology at Aarhus University, explains that archaeologists are still working to date the fortress more precisely.
"We would like to determine a specific year. The carbon-14 method can't provide that, but we are working on different methods that can help us date the fortress even more precisely."

Dating the fortress will be an important step towards understanding its role in the history of the Viking age.

"We can't say whether or not it's Harald Bluetooth's fortress yet, but now that we've dated it to the 10th century, the trail is getting hotter. The things we've discovered about the fortress during the excavations all point in the same direction. We already know that there's a good chance that we'll find conclusive evidence next year," says Sindbæk.

A structure meant to symbolise power

Even though the excavations have closed for this year, the finds bode well for future efforts. The archaeologists' investigations have also revealed that the Viking fortress was built right next to the open sea.

"The excavation showed that there was a basin of fresh or brackish water right next to one side of the fortress -- presumably a quite narrow inlet leading out to Køge Bay. When the fortress was built, hundreds of tonnes of the heavy clay subsoil would have had to have been dug out into the sea basin," explains Nanna Holm.

According to Nanna Holm, this work was undertaken for no other reason than to give the fortress an impressive location. The structure was meant to signal power.

The same master builder may be responsible

The excavation has also shown that the construction of the fortress is closely related to other Viking fortresses such as Fyrkat near Hobro, Aggersborg near the Limfjord and Trelleborg near Slagelse. These fortresses were undoubtedly built during the reign of Harald Bluetooth, and still more evidence suggests that Borgring, as the fortress has been named, might have belonged to the same building programme.

"There are a lot of similar details in these structures. And it's been wonderful to see the same things coming to light at Borgring. In addition to the structure of the rampart and the gates, we have also found traces of a street with wood paving running along the inside of the rampart -- just like in Fyrkat, Aggersborg and Trelleborg. The most striking thing, however, is the measurements of the fortress. The rampart of Borgring is 10.6 metres wide. That is exactly the same width as the rampart of Fyrkat. So it's hard to avoid the sense that the same master builder was responsible," says Sindbæk.

Source: Aarhus University

Findings at viking archaeological site show power trumping practicality

Baylor archeologist Davide Zori and assistant at Viking farmstead. Credit: Image courtesy of Baylor University

Vikings are known for raiding and trading, but those who settled in Iceland centuries ago spent more time producing and consuming booze and beef -- in part to gain political clout in a place very different from their Scandinavian homeland, says a Baylor University archaeologist.

The seafaring warriors wanted to sustain the "big man" society of Scandinavia -- a political economy in which chieftains hosted huge feasts of beer and beef served in great halls, says Davide Zori, Ph.D., a Denmark native and archeological field director in Iceland, who conducted National Science Foundation-funded research in archeology and medieval Viking literature.
But instead, what Zori and his team discovered is what happened when the Vikings spent too long living too high on the hog -- or, in this case, the bovine. 

"It was somewhat like the barbecue here. You wanted a big steak on the grill," said Zori, assistant professor in the Baylor Interdisciplinary Core. He co-edited the book Viking Archaeology in Iceland: Mosfell Archaelogical Project with Jesse Byock, Ph.D., professor of Old Norse and medieval Scandinavian studies at the University of California, Los Angeles.

"It made it really showy -- if you could keep it up." The Viking chieftains used such wealth and cultural displays to flex political muscle with equals or rivals -- plus to cement good relations with local laborers, Zori said.

Zori and Byock's team excavated a farmstead called Hrísbrú in Iceland's Mosfell Valley. The farm -- inhabited by some of the most famous Vikings of the Icelandic sagas -- included a chieftain's longhouse nearly 100 feet long with a "feast-worthy" great hall, a church and a cemetery of 26 graves indicating a mix of pagan and Christian traditions. Males sometimes were buried with ship remnants rather than in the simpler Christian manner of leaving earthly possessions behind.

Carbon dating and studies of volcanic layers indicate the longhouse was built in the late ninth or early 10th century and abandoned by the 11th. The archeological team uncovered 38 layers of floor ash, including refuse dumped atop the abandoned house, also discovering bones, barley seeds and valuable glass beads imported from Asia. "By applying anthropology and medieval texts, we can excavate and compare," Zori said.

Viking sagas, first written in the 13th century and based on oral accounts, included such details as where people sat at feasts, "which shows your ranking . . . These texts read almost like novels. They're incredible sources. They talk about daily life," Zori said.

"Yes, the Vikings may have put axes to one another's heads -- but these accounts also describe milking cows."

High Times and Hard Times

When the Vikings arrived in uninhabited Iceland, they found forested lowlands, ample pastures and sheltered sea inlets. Excavations show that choice cattle were selected for feasts, with ritual slaughter and display of skulls, according to research published by Zori and others in the journal Antiquity. Barley seeds unearthed from floors or refuse heaps indicate barley consumption, and pollen studies demonstrate barley cultivation. Barley could have been used for bread or porridge, but beer's social value makes it very likely barley was used mainly to produce alcohol, Zori said.

Over centuries, as temperatures in the North Atlantic dropped during the "Little Ice Age," being a lavish host got tougher. "Nine months of winter -- and three months that are only a little less than winter," Zori said.

While sheep could find food free range most of the year and were suited for cold, prized cattle had to be kept indoors in large barns during the winter. Savvy supply-and-demand reckoning was crucial to be sure the food lasted -- both for cattle and humans -- and could be preserved.

"They had to decide how many to slaughter and store," Zori said. "They didn't have salt, so they had to use big vats of curdled milk as a preservative." As the landscape changed due to erosion, climate shifts and cleared forests, it became harder to rear larger numbers of cattle.

High-status households also struggled to grow enough grain for beer-making, based on historical accounts and confirmed by a growing body of archeological data. With a shorter growing season and colder climate than in their homelands, Icelandic Vikings would have needed more laborers to improve the soil -- and as the chieftains' power waned, they would have had trouble attracting workers. As barley cultivation stopped, the local chieftains are no longer mentioned in the Viking sagas.

Changing Directions

"You can see in the archeological evidence that they adjusted their strategy and gave it up eventually," Zori said. "It got harder and harder to keep up that showiness -- and when that collapsed, you didn't have that power, that beer and big slabs of beef to show off."

When barley was abandoned, the pollen record shows native grasses for grazing increased. Archeological findings show that the proportion of cattle to sheep bones declined, as Hrísbrú residents shifted to more practical, less laborious sheep-herding.

"You wonder what came first for the chieftains at Hrísbrú: Were they no longer powerful and didn't need barley and beef? Or could they just not keep it up and so they lost power? I favor the second explanation," Zori said.

"What we're doing now is to let the archaeology speak, both for itself and for proof to verify (the texts)," he said. "Investigating politics breathes life into it, instead of just saying, 'Here are three rocks.' You can ask deeper questions."
Zori argues that Viking chieftains' drive to produce expensive beef and beer caused them to put their political aspirations above the greater good of the community.

"Maybe we don't need the Vikings to prove this," he said. "But it shows you that politics can become more important than creating a productive society."

Source: Baylor University

Major Viking hall identified in Sweden

Using ground-penetrating radar. Credit: Martin Rundkvist

A Viking feasting hall measuring almost 50 metres in length has been identified near Vadstena in Sweden. Archaeologists from Stockholm University and Umeå University used ground-penetrating radar, a non-invasive geophysical method, to locate and map the house foundation. The study was published today in the journal Archaeological Prospection.

The Aska barrow, where the hall has been found, was long seen as a burial mound. But archaeologists have now revealed that it is a foundation platform for a large building, most likely dating from the Viking Period. The hall was probably the home of a royal family whose rich graves have previously been excavated nearby.

"Parallels are known from several of the era's elite sites, such as Fornsigtuna near Stockholm and Lejre near Roskilde. The closest similarities are however seen in a recently excavated feasting hall at Old Uppsala near Stockholm. Such close correspondences suggest intensive communication between the two sites," says Martin Rundkvist of Umeå University

The building was about 14 metres wide and was equipped with double walls and four entrances. The measurements also indicate a large fireplace at the centre of the floor.

"Our investigation demonstrates that non-invasive geophysical measurements can be powerful tools for studying similar building foundations elsewhere. They even allow scholars to estimate the date of a building without any expensive excavations," says Andreas Viberg of the Archaeological Research Laboratory at Stockholm University who directed the fieldwork.

Source: Stockholm University

Archaeologists reveal layout of medieval city at Old Sarum

Old Sarum -- aerial photo. Credit: Image courtesy of University of Southampton

Archaeologists from the University of Southampton have revealed for the first time the plan of a network of buildings in a once thriving medieval city at the historic site of Old Sarum, near Salisbury.

A research team of students and academics carried out a geophysical survey of the ancient monument, scanning ground at the site with state-of-the-art equipment to map the remains of buried structures. They concentrated their survey around the inner and outer baileys of what was once a fortification, with its origins in the Iron Age and the Roman conquest.1

Their investigations reveal the layout of a settlement including structures from the late 11th century, contemporary with the construction of a cathedral and castle. The city was inhabited for over 300 years, but declined in the 13th century with the rise of New Sarum (Salisbury).

The project findings mainly concentrate on the medieval period and highlight:

* A series of massive structures along the southern edge of the outer bailey defensive wall, perhaps suggesting large buildings of a defensive nature.
* An open area of ground behind these large structures, perhaps for mustering resources or people, or as part of a circular route through the city..
* Residential areas in the south east and south west quadrants of the outer bailey alongside the inner bailey ditch.
* Evidence of deposits indicating industrial features, such as kilns or furnaces.
* Features suggesting quarrying at the site after the 1300s and following the city's decline -- indicating a later period of habitation at the site..

Archaeologist Kristian Strutt, Experimental Officer and Director of Archaeological Prospection Services at the University of Southampton, says: "Archaeologists and historians have known for centuries that there was a medieval city at Old Sarum, but until now there has been no proper plan of the site.

"Our survey shows where individual buildings are located and from this we can piece together a detailed picture of the urban plan within the city walls."

The research was conducted as part of the Old Sarum and Stratford-Sub-Castle Archaeological Survey Project, directed by Kristian Strutt and fellow Southampton archaeologists Timothy Sly and Dominic Barker. Old Sarum is under the custodianship of English Heritage, who kindly granted permission for the investigation to take place.

Heather Sebire, Property Curator at English Heritage, comments: "Having the team of archaeologists on site over the summer gave our visitors a chance to find out more about how important historic landscapes are surveyed. The use of modern, non-invasive surveying is a great start to further research at Old Sarum.

"From this work we can surmise much about the site's past and, whilst we can't conclusively date the findings, it adds a new layer to Old Sarum's story. We welcome the chance to find out more about our sites, and look forward to exploring ideas for further research in the future."

The team used a variety of techniques to examine the outer and inner bailey of the site. These included the use of topographic survey methods and geophysical survey techniques -- comprising of magnetometry, earth resistance, ground penetrating radar (GPR) and electric resistivity tomography (ERT) survey.

Kristian Strutt concludes: "Our research so far has shown how the entire outer bailey of the monument was heavily built up in the Middle Ages, representing a substantial urban centre. Results have given us compelling evidence as to the nature of some of the structures. It is clear, however, that there is more non-intrusive work that could be carried out to further expand our understanding of the site."

The team hopes to return to complete the survey of the inner and outer baileys and survey the Romano-British settlement to the south of Old Sarum in Easter 2015. The project fieldwork in 2014 was used as a training season for undergraduate and postgraduate archaeology students at the University, continuing a long tradition of research-led teaching at some of the most impressive archaeological sites in the south of England. Previous fieldwork has been conducted by students at Portchester Castle, Netley Abbey and Bishop's Waltham Palace in Hampshire, and at Bodiam Castle in East Sussex.

Source: University of Southampton

Were Neanderthals a sub-species of modern humans? New research says no

Depiction of Neanderthal (stock image). Credit: © procy_ab / Fotolia

In an extensive, multi-institution study led by SUNY Downstate Medical Center, researchers have identified new evidence supporting the growing belief that Neanderthals were a distinct species separate from modern humans (Homo sapiens), and not a subspecies of modern humans.

The study looked at the entire nasal complex of Neanderthals and involved researchers with diverse academic backgrounds. Supported by funding from the National Science Foundation and the National Institutes of Health, the research also indicates that the Neanderthal nasal complex was not adaptively inferior to that of modern humans, and that the Neanderthals' extinction was likely due to competition from modern humans and not an inability of the Neanderthal nose to process a colder and drier climate.

Samuel Márquez, PhD, associate professor and co-discipline director of gross anatomy in SUNY Downstate's Department of Cell Biology, and his team of specialists published their findings on the Neanderthal nasal complex in the November issue of The Anatomical Record, which is part of a special issue on The Vertebrate Nose: Evolution, Structure, and Function (now online).

They argue that studies of the Neanderthal nose, which have spanned over a century and a half, have been approaching this anatomical enigma from the wrong perspective. Previous work has compared Neanderthal nasal dimensions to modern human populations such as the Inuit and modern Europeans, whose nasal complexes are adapted to cold and temperate climates.

However, the current study joins a growing body of evidence that the upper respiratory tracts of this extinct group functioned via a different set of rules as a result of a separate evolutionary history and overall cranial bauplan (bodyplan), resulting in a mosaic of features not found among any population of Homo sapiens. Thus Dr. Márquez and his team of paleoanthropologists, comparative anatomists, and an otolaryngologist have contributed to the understanding of two of the most controversial topics in paleoanthropology -- were Neanderthals a different species from modern humans and which aspects of their cranial morphology evolved as adaptations to cold stress.

"The strategy was to have a comprehensive examination of the nasal region of diverse modern human population groups and then compare the data with the fossil evidence. We used traditional morphometrics, geometric morphometric methodology based on 3D coordinate data, and CT imaging," Dr. Márquez explained.

Anthony S. Pagano, PhD, anatomy instructor at NYU Langone Medical Center, a co-author, traveled to many European museums carrying a microscribe digitizer, the instrument used to collect 3D coordinate data from the fossils studied in this work, as spatial information may be missed using traditional morphometric methods. "We interpreted our findings using the different strengths of the team members," Dr. Márquez said, "so that we can have a 'feel' for where these Neanderthals may lie along the modern human spectrum."

Co-author William Lawson, MD, DDS, vice-chair and the Eugen Grabscheid research professor of otolaryngology and director of the Paleorhinology Laboratory of the Icahn School of Medicine at Mount Sinai, notes that the external nasal aperture of the Neanderthals approximates some modern human populations but that their midfacial prognathism (protrusion of the midface) is startlingly different. That difference is one of a number of Neanderthal nasal traits suggesting an evolutionary development distinct from that of modern humans. Dr. Lawson's conclusion is predicated upon nearly four decades of clinical practice, in which he has seen over 7,000 patients representing a rich diversity of human nasal anatomy.

Distinguished Professor Jeffrey T. Laitman, PhD, also of the Icahn School of Medicine and director of the Center for Anatomy and Functional Morphology, and Eric Delson, PhD, director of the New York Consortium in Evolutionary Primatology or NYCEP, are also co-authors and are seasoned paleoanthropologists, each approaching their fifth decade of studying Neanderthals. Dr. Delson has published on various aspects of human evolution since the early 1970's.

Dr. Laitman states that this article is a significant contribution to the question of Neanderthal cold adaptation in the nasal region, especially in its identification of a different mosaic of features than those of cold-adapted modern humans. Dr. Laitman's body of work has shown that there are clear differences in the vocal tract proportions of these fossil humans when compared to modern humans. This current contribution has now identified potentially species-level differences in nasal structure and function.

Dr. Laitman said, "The strength of this new research lies in its taking the totality of the Neanderthal nasal complex into account, rather than looking at a single feature. By looking at the complete morphological pattern, we can conclude that Neanderthals are our close relatives, but they are not us."

Ian Tattersall, PhD, emeritus curator of the Division of Anthropology at the American Museum of Natural History, an expert on Neanderthal anatomy and functional morphology who did not participate in this study, stated, "Márquez and colleagues have carried out a most provocative and intriguing investigation of a very significant complex in the Neanderthal skull that has all too frequently been overlooked." Dr. Tattersall hopes that "with luck, this research will stimulate future research demonstrating once and for all that Homo neanderthalensis deserves a distinctive identity of its own."

Source: SUNY Downstate Medical Center

How culture influences violence among the Amazon's ‘fierce people'

In this mid-1960s photo, men from two Yanomamo villages in the Amazon engage in nonhostile combat to determine the strength and fighting prowess of potential alliance partners. A new study from the University of Utah and University of Missouri indicates the Yanomamo -- who engaged in killing to gain status in past decades -- often formed alliances with men in different villages when they attacked and killed people in other communities, then married their allies' sisters or daughters. The idea is they fought like a 'band of brothers-in-law' more than a closely related 'band of brothers,' fathers and sons from a single community. [show less] Credit: Napoleon Chagnon

When Yanomamö men in the Amazon raided villages and killed decades ago, they formed alliances with men in other villages rather than just with close kin like chimpanzees do. And the spoils of war came from marrying their allies' sisters and daughters, rather than taking their victims' land and women.

Those findings -- which suggest how violence and cooperation can go hand-in-hand and how culture may modify any innate tendencies toward violence -- come from a new study of the so-called "fierce people" led by provocative anthropologist Napoleon Chagnon and written by his protégé, University of Utah anthropologist Shane Macfarlan.

Macfarlan says the researchers had expected to find the Yanomamö fought like "bands of brothers" and other close male kin like fathers, sons and cousins who live in the same community and fight nearby communities. That is how fights are conducted by chimpanzees -- the only other apes besides humans that form coalitions to fight and kill.

Instead, "a more apt description might be a 'band of brothers-in-law,'" in which Yanomamö men ally with similar-age men from nearby villages to attack another village, then marry their allies' female kin, Macfarlan, Chagnon and colleagues write in the study, published this week in the journal Proceedings of the National Academy of Sciences.

The study provides a mechanism to explain why Yanomamö warriors in a 1988 Chagnon study had more wives and children than those who did not kill.

"We are showing these guys individually get benefits from engaging in killing," Macfarlan says. "They're getting long-term alliance partners -- other guys they can trust to get things done. And they are getting marriage opportunities."

Since his 1968 book "Yanomamö: The Fierce People," Chagnon has been harshly criticized by some cultural anthropologists who claim he places undue emphasis on genes and biology as underpinnings of human violence, based on his 1964-1993 visits to the Yanomamö. Defenders such as Macfarlan say Chagnon takes a much more balanced view, and that "it's never a genes-versus-culture argument. They operate in tandem."

Chagnon got what was seen as vindication in 2012 when he was elected to the National Academy of Sciences. The new study, with Macfarlan as first author and Chagnon as senior author -- is Chagnon's inaugural PNAS article as a member.

Macfarlan joined the University of Utah faculty this year an assistant professor of anthropology. He worked as Chagnon's postdoctoral fellow at the University of Missouri from January 2013 to June 2014. Chagnon and Macfarlan conducted the study with two Missouri colleagues: anthropologists Robert S. Walker and Mark V. Flinn.

Models of Warfare

The Yanomamö -- hunters and farmers who live in southern Venezuela and northern Brazil -- once gained social status as "unokai" for killing.

Up to 20 Yanomamö (pronounced yah-NO-mama, but also spelled Yanomami or Yanomama) would sneak up on another village at dawn, "shoot the first person they saw and then hightail back home," Macfarlan says. Some Yanomamö men did this once, some up to 11 times and some never killed. (Data for the study, collected in the 1980s, covered somewhat earlier times when spears, bows and arrows were the primary weapons.)

Macfarlan says the classic debate has been, "does warfare in small-scale societies like the Yanomamö resemble chimpanzee warfare?" -- a theory known as the "fraternal interest group" model, in which bands of brothers, fathers, sons and paternal uncles all living in the same community fight other similar communities.

The new study asked whether Yanomamö killing follows that model or the "strategic alliance model," which the researchers dub the "band of brothers-in-law" model. This model -- supported by the study's findings -- indicates that Yanomamö men form alliances not with close kin from the same community, but with men from other communities. After killing together, a bond is formed and they often marry each other's daughters or sisters and move into one or the other's village or form a new village.

"When we started off this project, we all assumed it would be the chimpanzee-like model. But in human groups we have cultural rules that allow us to communicate with other communities. You certainly don't see chimpanzees doing this."

Is the study a retreat from what Chagnon's critics see as too much focus on genetic and biological underpinnings of violence? Macfarlan says no, that Chagnon "has never been as all-biology as people have painted him. Most of his published research shows how unique cultural rules make the Yanomamö an interesting group of people."

Earlier research suggested that for chimps, warfare is adaptive in an evolutionary sense, and that it also benefits small-scale human societies. The new study asked, "If warfare is adaptive, in what way do the adaptive benefits flow?" Macfarlan says.

"Some people, myself included, said, to the victor goes the spoils, because if you conquer another territory, you might take their land, food or potentially their females."

But the new study indicates "the adaptive benefits are the alliances you build by perpetrating acts of warfare," he adds. "It's not that you are taking land or females from the vanquished group, but for the Yanomamö, what you acquire is that you can exchange resources with allies, such as labor and, most importantly, female marriage partners."

The study's findings that the Yanomamö form strategic alliances to kill suggest that "our ultracoooperative tendencies tend to go hand-in-hand with our ultralethal tendencies," Macfarlan says. "We show a relationship between cooperation and violence at a level unseen in other organisms." That may seem obvious for allied nations in modern wars, but "we're saying that even in small-scale societies this is the case."

How the Study was Conducted

The new study analyzed data collected by Chagnon in the 1980s, when about 25,000 Yanomamö lived in about 250 villages ranging from 25 to 400 people.
The study examined 118 Yanomamö warriors or unokai who had killed a total of 47 people by forming raiding parties of two to 15 men. The researchers analyzed the relationships between every possible pair of men in those raiding parties. Among the 118 unokai men, there were 509 possible pairs. Macfarlan says the findings revealed surprises about the relationship between co-unokai -- pairs of men who kill together:

-- Only 22 percent of men who kill together were from the same lineage.

-- Only 34 percent of co-unokai pairs were from the same place of birth. "Guys who come from different places of birth are more likely to kill together."

-- Among co-killers known to be related, a majority were related on their mother's side rather than their father's side -- more evidence of forming alliances beyond the immediate paternal kinship group. In Yanomamö culture, true kin are viewed as being on the paternal side, while maternal relatives are seen as belonging to another social group.

-- The Yanomamö preferred forming coalitions with men within a median of age difference of 8 years. "The more similar in age, the more likely they will kill multiple times," Macfarlan says.

-- Of the 118 unokai, 102 got married in a total of 223 marriages to 206 women. Of married killers, 70 percent married at least one woman from the same paternal line as an ally in killing. And "the more times they kill together, the more likely they are going to get marriage partners from each other's family line," Macfarlan says.

-- As a result, "The more times the guys kill together, the more likely they are to move into the same village later in life, despite having come from different village."

The study found allies-in-killing often are somewhere between maternal first and second cousins, Macfarlan says. Under Yanomamö rules, a man's ideal marriage partner is a maternal first cousin, who would be the offspring of your mother's brother. He says Yanomamö rules allow marriage to a maternal first cousin, but not a paternal first cousin.

Despite debate over the biological roots of deadly coalitions in chimps and humans, the new study shows how culture can make it "uniquely human" because if Yanomamö men "kill together, they are plugged into this social scene, this marriage market," Macfarlan says. "They are playing the game of their culture."

Source: University of Utah

Uncovering one of humankind’s most ancient lineages

A Khoisan hunter/gatherer with his bow and arrows. Credit: Image courtesy of Nanyang Technological University

Scientists at Nanyang Technological University (NTU Singapore) and Penn State University in the United States have successfully discovered one of modern humans' ancient lineages through the sequencing of genes.

A geneticist from NTU, Professor Stephan Christoph Schuster, who led an international research team from Singapore, United States and Brazil, said this is the first time that the history of humankind populations has been analysed and matched to Earth's climatic conditions over the last 200,000 years.
Their breakthrough findings are published today (4 Dec) in Nature Communications.

The team has sequenced the genome of five living individuals from a hunter/gatherer tribe in Southern Africa, and compared them with 420,000 genetic variants across 1,462 genomes from 48 ethnic groups of the global population.

Through advanced computation analysis, the team found that these Southern African Khoisan tribespeople are genetically distinct not only from Europeans and Asians, but also from all other Africans.

The team also found that there are individuals of the Khoisan population whose ancestors did not interbreed with any of the other ethnic groups for the last 150,000 years and that Khoisan was the majority group of living humans for most of that time until about 20,000 years ago.

Their findings mean it is now possible to use genetic sequencing to reveal the ancestral lineage of any ethnic group even up to 200,000 years ago, if non-admixed individuals are found, like in the case of the Khoisan. This will show when in history there have been important genetic changes to an ancestral lineage due to intermarriages or geographical migrations that may have occurred over the centuries.

"Khoisan hunter/gatherers in Southern Africa have always perceived themselves as the oldest people," said Prof Schuster, an NTU scientist at the Singapore Centre on Environmental Life Sciences Engineering (SCELSE) and a former Penn State University professor.

"Our study proves that they truly belong to one of mankind's most ancient lineages, and these high quality genome sequences obtained from the tribesmen will help us better understand human population history, especially the understudied branch of mankind such as the Khoisan.

"The new data gathered will also enable scientists to better understand how the human genome has evolved and hopefully lead to more effective treatment options for certain genetic diseases and illnesses."

Of the five tribesmen who were the oldest members of the Ju/'hoansi tribe and other tribes living in protected areas of northwest Namibia, two individuals were found to have a genome which had not admixed with other ethnic groups.

The Ju/'hoansi tribe was made famous in the 80s and 90s by the box-office hit movie series "The Gods Must Be Crazy." The main character of the series was a hunter/gatherer tribesman, played by Nǃxau, a bushman.

The research paper's first author, Dr Hie Lim Kim, a SCELSE senior research fellow, said "it was very surprising that this group apparently did not intermarry with non-Khoisan neighbours for thousands of years." This is because the Khoisan peoples and the rest of modern humanity shared their most recent common ancestor around 150,000 years ago.

The current Khoisan culture and tradition, where marriage occurs either among Khoisan groups or results in female members leaving their tribes after marrying non-Khoisan men, appears to be long-standing.

"A key finding from this study is that even today after 150,000 years, single non-admixed individuals or descendants of those who did not interbreed with separate populations can be identified within the Ju/'hoansi population, which means there might be more of such unique individuals in other parts of the world," added Dr Kim.

The Khoisan tribespeople participating in this study had parts of their genomes sequenced in an earlier study by the same team in 2010. The new study generated complete genome sequences at high quality, which enabled the analysis of admixture and population history. The availability of such high quality Southern African genomes will allow further investigation of the population history of this largely understudied branch of humankind at high resolution.

This research project involving six investigators was led by NTU and Penn State University. Other institutions participating in the study include the Ohio State University and Sao Paulo State University, Brazil.

Moving forward, Prof Schuster added that they will be looking to find more non-admixed individuals who are in the other parts of the world, such as in South Asia and South America, where uncontacted tribes still exist. The team will also be seeking more funding to further their research which will have large impact on the study of life sciences.

Source: Nanyang Technological University

Oldest stone tool ever found in Turkey discovered

Stone tool approximately 1.2 million years old. Credit: Image courtesy of University of Royal Holloway London

Scientists have discovered the oldest recorded stone tool ever to be found in Turkey, revealing that humans passed through the gateway from Asia to Europe much earlier than previously thought, approximately 1.2 million years ago.

According to research published in the journal Quaternary Science Reviews, the chance find of a humanly-worked quartzite flake, in ancient deposits of the river Gediz, in western Turkey, provides a major new insight into when and how early humans dispersed out of Africa and Asia.

Researchers from Royal Holloway, University of London, together with an international team from the UK, Turkey and the Netherlands, used high-precision equipment to date the deposits of the ancient river meander, giving the first accurate timeframe for when humans occupied the area.

Professor Danielle Schreve, from the Department of Geography at Royal Holloway, said: "This discovery is critical for establishing the timing and route of early human dispersal into Europe. Our research suggests that the flake is the earliest securely-dated artefact from Turkey ever recorded and was dropped on the floodplain by an early hominin well over a million years ago."

The researchers used high-precision radioisotopic dating and palaeomagnetic measurements from lava flows, which both pre-date and post-date the meander, to establish that early humans were present in the area between approximately 1.24 million and 1.17 million years ago. Previously, the oldest hominin fossils in western Turkey were recovered in 2007 at Koçabas, but the dating of these and other stone tool finds were uncertain.

"The flake was an incredibly exciting find," Professor Schreve said. "I had been studying the sediments in the meander bend and my eye was drawn to a pinkish stone on the surface. When I turned it over for a better look, the features of a humanly-struck artefact were immediately apparent.

"By working together with geologists and dating specialists, we have been able to put a secure chronology to this find and shed new light on the behaviour of our most distant ancestors."

Source: University of Royal Holloway London

Parasites and the evolution of primate culture

Chimpanzees (stock image). A new study examines the ‘costs’ of innovation, and learning from others. Credit: © shiruikage / Fotolia

Learning from others and innovation have undoubtedly helped advance civilization. But these behaviours can carry costs as well as benefits. And a new study by an international team of evolutionary biologists sheds light on how one particular cost -- increased exposure to parasites -- may affect cultural evolution in non-human primates.

The results, published Dec. 3, 2014 in the journal Proceedings of the Royal Society B, suggest that species with members that learn from others suffer from a wider variety of socially transmitted parasites, while innovative, exploratory species suffer from a wider variety of parasites transmitted through the environment, such as in the soil or water.

"We tend to focus on innovation and learning from others as a good thing, but their costs have received relatively little attention," says McGill University biologist Simon Reader, co-author of the study. "Here, we uncover evidence that socially transmitted pathogen burdens rise with learning from others -- perhaps because close interaction is needed for such learning -- and environmentally transmitted pathogen burdens rise with exploratory behaviour such as innovation and extractive foraging."

Chimpanzees, for example, live in groups and have a wide range of such behaviours, such as digging for food underground or eating new kinds of insects.. Previously, studies have not been able to determine whether costly parasites force primates to engage in more exploratory behaviour -- by diversifying food sources, for example -- or whether exploratory behaviour leads to their having more parasites, Reader notes. "Our results support the idea that exploratory and social behaviours expose primates to specific kinds of parasites."

"The findings also lead to questions about how people and other primates have developed solutions to minimize these parasite costs -- such as eating medicinal plants -- and may help us better understand how the processes underlying human culture arose," Reader says.
The research team, led by Collin McCabe of Harvard University and Charles Nunn of Duke University, based their analyses on databases obtained by surveying thousands of articles on primate behaviour and parasites.

Funding for the research was provided by the National Science Foundation, the Natural Sciences and Engineering Research Council of Canada, and the Netherlands Organisation for Scientific Research.

Source: McGill University

Remote surveillance may increase chance of survival for 'uncontacted' Brazilian tribes

Members of an uncontacted tribe in the Brazilian state of Acre, as seen from satellite images.
Photo courtesy of Government of Brazil.
Credit: Image courtesy of University of Missouri-Columbia

Lowland South America, including the Amazon Basin, harbors most of the last indigenous societies that have limited contact with the outside world. Studying these tribes, located deep within Amazonian rainforests, gives scientists a glimpse at what tribal cultures may have been like before the arrival of Europeans. Now, researchers at the University of Missouri have used satellite images to assess the demographic health of one particular village of isolated people on the border between Brazil and Peru. Remote surveillance is the only method to safely track uncontacted indigenous societies and may offer information that can improve their chances for long-term survival.

Rob Walker, an assistant professor of anthropology in the College of Arts and Science at MU, collaborated with Marcus Hamilton, postdoctoral fellow at the Santa Fe Institute and adjunct assistant professor of anthropology at the University of New Mexico. They used Google Earth satellite imagery to estimate the area of the fields and the size of the village belonging to the tribe, as well as the living area of the tribe's temporary housing, and compared that with similar estimates for 71 other Brazilian indigenous communities.

"We found that the estimated population of the village is no more than 40 people," Walker said. "A small, isolated village like this one faces an imminent threat of extinction. However, forced contact from the outside world is ill-advised, so a non-invasive means of monitoring the tribe is recommended. A remote surveillance program using satellite images taken periodically of this group would help track the movements and demographic health of the population without disrupting their lives."

Using information captured from remote surveillance, scientists can help shape policies that mitigate the threats of extinction including deforestation, illegal mining and colonization in these remote areas. Additionally, surveillance also can help locate isolated villages, track patterns of migration over time, and inform and create boundaries or buffer zones that would allow tribes to stay isolated, Walker said.
"Close to 100 uncontacted groups are thought to currently exist in Amazonia," Walker said.

"Deforestation, cattle ranching, illegal mining, and outside colonization threaten their existence. Most of these tribes are swidden horticulturalists and so their slash-and-burn fields are observable in satellite images. But, they do move around, sometimes in response to external threats, and this movement requires constant monitoring if there is to be any hope of preserving their habitat and culture."

The study, "Amazonian societies on the brink of extinction," was published online in The American Journal of Human Biology.

Source: University of Missouri-Columbia.

Hippos-Sussita excavation: Silent evidence of the earthquake of 363 CE

The city of Hippos-Sussita, which was founded in the second century BCE, experienced two strong and well-documented earthquakes. The first was in the year 363 CE and it caused heavy damage. The city, did, however, recover. The great earthquake of 749 CE destroyed the city which was subsequently abandoned completely. Evidence of the extensive damage caused by the earthquake of 363 was found in earlier seasons. None, however, was as violent, thrilling and eerie as the evidence discovered this year. Credit: Image courtesy of University of Haifa

Silent evidence of a large earthquake in 363 CE -- the skeleton of a woman with a dove-shaped pendant was discovered under the tiles of a collapsed roof by archeologists from the University of Haifa during this excavation season at Hippos-Sussita. They also found a large muscular marble leg and artillery ammunition from some 2,000 years ago. "The data is finally beginning to form a clear historical-archaeological picture," said Dr. Michael Eisenberg, head of the international excavation team.

The past fifteen excavation seasons at Hippos-Sussita, run by archeologists from the Zinman Institute of Archaeology at the University of Haifa, have not stopped providing a constant flow of fascinating findings. The team digging at the city site -- situated east of the Sea of Galilee in the Sussita National Park, which is under the management of the Israel Nature and Parks Authority -- has grown over the years, with more and more teams and excavators from various countries joining them. This time, the security situation in the south of Israel "sent" them a Canadian team, led by Dr. Stephen Chambers, as reinforcement.

The city of Hippos-Sussita, which was founded in the second century BCE, experienced two strong and well-documented earthquakes. The first was in the year 363 CE and it caused heavy damage. The city, did, however, recover. The great earthquake of 749 CE destroyed the city which was subsequently abandoned completely. Evidence of the extensive damage caused by the earthquake of 363 was found in earlier seasons. None, however, was as violent, thrilling and eerie as the evidence discovered this year.

To the north of the basilica, the largest building in town that served as the commercial, economic and judicial center of the city, the dig's senior area supervisor Haim Shkolnik and his team unearthed the remains of several skeletons that had been crushed by the weight of the collapsed roof. Among the bones of one of the women lay a gold dove-shaped pendant.

This year, evidence was found for the first time that the great earthquake of 363 CE had destroyed the Roman bathhouse, which was uncovered by the team run by Arleta Kowalewska from Poland. Like the basilica, it too was not rebuilt. According to Dr. Eisenberg, the evidence found so far shows that the earthquake was so powerful it completely destroyed the city, which took some twenty years to be rebuilt. Among the wreckage from the bathhouse, an excellent Roman marble sculpture of a muscular right leg of a man leaning against a tree trunk was found. "It is too early to determine who the man depicted in the sculpture was. It could be the sculpture of a god or an athlete; it was more than two meters tall. We hope to find more parts of the sculpture in the coming seasons to shed some light on his identity," said Dr. Eisenberg.

Excavations were resumed in the bastion, the main defense post of the Roman period city built on the southern edge of the cliff, where the work focused on the fortified position of a projectile machine that propelled/launched ballista stones. The catapult was some eight meters long according to the size of the chamber. So far the archeologists have found a number of ballista balls that fit the massive catapult, as well as smaller balls that were used on smaller ballista machines. These machines were positioned above the bastion's vaults and were used to launch basalt ballista balls slightly smaller than soccer balls as far as 350 meters.

A section of the western part of the city's main colonnaded street, which traversed its entire length of 600 meters from east to west (the decumanus maximus) was excavated this year with the help of a Canadian team, after their planned dig in the south was cancelled. The archeologists uncovered another original piece of the wall that supported the street columns, confirming the theory that it had been a magnificent colonnaded street similar to those of the Roman East cities that were built at the peak of the Pax Romana -- the Roman era of peace during the first few centuries CE.

While working on the dig the team also invested a lot of work on the site's conservation. "I am extremely proud that we were able to organize a sizable conservation team this year as well, from our own internal budgets and with the help of the Western Galilee College in Acre. Twenty-two students from the college's Department of Conservation together with five experienced conservators under the direction of Julia Burdajewicz from the Academy of Fine Arts in Warsaw conducted the conservation work. This is one of the major tourist destinations in the northern part of the country, and as such I see this as a national mission, even if the budget comes primarily from our own sources, without government support," concluded Dr. Eisenberg.

Source: University of Haifa