Sunday, March 31, 2013

Human cognition depends upon slow-firing neurons

Good mental health and clear thinking depend upon our ability to store and manipulate thoughts on a sort of "mental sketch pad." In a new study, Yale School of Medicine researchers describe the molecular basis of this ability — the hallmark of human cognition — and describe how a breakdown of the system contributes to diseases such as schizophrenia and Alzheimer's disease.

"Insults to these highly evolved cortical circuits impair the ability to create and maintain our mental representations of the world, which is the basis of higher cognition," said Amy Arnsten, professor of neurobiology and senior author of the paper published in the Feb. 20 issue of the journal Neuron.

High-order thinking depends upon our ability to generate mental representations in our brains without any sensory stimulation from the environment. These cognitive abilities arise from highly evolved circuits in the prefrontal cortex. Mathematical models by former Yale neurobiologist Xiao-Jing Wang, now of New York University, predicted that in order to maintain these visual representations the prefrontal cortex must rely on a family of receptors that allow for slow, steady firing of neurons. The Yale scientists show that NMDA-NR2B receptors involved in glutamate signaling regulate this neuronal firing. These receptors, studied at Yale for more than a decade, are responsible for activity of highly evolved brain circuits found especially in primates.

Earlier studies have shown these types of NMDA receptors are often altered in patients with schizophrenia. The Neuron study suggests that those suffering from the disease may be unable to hold onto a stable view of the world. Also, these receptors seem to be altered in Alzheimer's patients, which may contribute to the cognitive deficits of dementia.

The lab of Dr. John Krystal, chair of the department of psychiatry at Yale, has found that the anesthetic ketamine, abused as a street drug, blocks NMDA receptors and can mimic some of the symptoms of schizophrenia. The current study in Neuron shows that ketamine may reduce the firing of the same higher-order neural circuits that are decimated in schizophrenia.

"Identifying the receptor needed for higher cognition may help us to understand why certain genetic insults lead to cognitive impairment and will help us to develop strategies for treating these debilitating disorders," Arnsten said.
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References:

EurekAlert. 2013. “Human cognition depends upon slow-firing neurons”. EurekAlert. Posted: February 20, 2013. Available online: http://www.eurekalert.org/pub_releases/2013-02/yu-hcd021813.php

Saturday, March 30, 2013

Language Protein Differs in Males, Females

Male rat pups have more of a specific brain protein associated with language development than females, according to a study published February 20 in The Journal of Neuroscience. The study also found sex differences in the brain protein in a small group of children. The findings may shed light on sex differences in communication in animals and language acquisition in people.

Sex differences in early language acquisition and development in children are well documented -- on average, girls tend to speak earlier and with greater complexity than boys of the same age. However, scientists continue to debate the origin and significance of such differences. Previous studies showed the Foxp2 protein plays an important role in speech and language development in humans and vocal communication in birds and other mammals.

In the current study, J. Michael Bowers, PhD, Margaret McCarthy, PhD, and colleagues at the University of Maryland School of Medicine examined whether sex differences in the expression of the Foxp2 protein in the developing brain might underlie communication differences between the sexes.

The researchers analyzed the levels of Foxp2 protein in the brains of four-day-old female and male rats and compared the ultrasonic distress calls made by the animals when separated from their mothers and siblings. Compared with females, males had more of the protein in brain areas associated with cognition, emotion, and vocalization. They also made more noise than females -- producing nearly double the total vocalizations over the five-minute separation period -- and were preferentially retrieved and returned to the nest first by the mother.

When the researchers reduced levels of the Foxp2 protein in the male pups and increased it in female pups, they reversed the sex difference in the distress calls, causing males to sound like females and the females like males. This change led the mother to reverse her behavior as well, preferentially retrieving the females over the males.

"This study is one of the first to report a sex difference in the expression of a language-associated protein in humans or animals," McCarthy said. "The findings raise the possibility that sex differences in brain and behavior are more pervasive and established earlier than previously appreciated."

The researchers extended their findings to humans in a preliminary study of Foxp2 protein in a small group of children. Unlike the rats, in which Foxp2 protein was elevated in males, they found that in humans, the girls had more of the Foxp2 protein in the cortex -- a brain region associated with language -- than age-matched boys.

"At first glance, one might conclude that the findings in rats don't generalize to humans, but the higher levels of Foxp2 expression are found in the more communicative sex in each species," noted Cheryl Sisk, who studies sex differences at Michigan State University and was not involved with the study.

This research was funded by the National Institute of Neurological Disorders and Stroke and the National Institute of Mental Health.
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References:

Science Daily. 2013. “Language Protein Differs in Males, Females”. Science Daily. Posted: February 19, 2013. Available online: http://www.sciencedaily.com/releases/2013/02/130219172153.htm

Friday, March 29, 2013

A New Way to Listen to Extinct Languages

Languages are like species. They evolve in mostly predictable ways, splitting into new species or dying out over time. Now, a group of linguists and computer scientists in the US and Canada have created a piece of software that can analyze enormous groups of languages to reconstruct what the earliest human languages might have sounded like.

It sounds like a subplot from Neal Stephenson's novel Snow Crash, but it's quite real. By using this program and others like it, linguists may one day know how people sounded when they talked 20,000 years ago, long before there was writing.

University of British Columbia statistician Alexandre Bouchard-Côté began working on the program when he was a graduate student at UC Berkeley. He used common algorithms to compare sounds and cognates — words that are the same in multiple languages — across hundreds of different modern languages.

By doing this, he could predict which language groups were most related to each other, and which kinds of sounds would be preserved most often. A sound that remained the same across distantly related languages was probably a sound that existed early in our linguistic evolutionary tree.

By putting these sounds together, Bouchard-Côté's program was able to reconstruct the sounds and words were most likely to have been used in languages from pre-history. Linguists speculate that the languages that led to today's modern ones include Proto-Indo-European, Proto-Afroasiatic and Proto-Austronesian. Bouchard-Côté and his colleagues focused on Proto-Austronesia, which led to today's Polynesian languages, as well as languages in Southeast Asia and parts of continental Asia. They were able to reconstruct over 600 ancient Proto-Austronesian languages.

In their paper, published this week in Proceedings of the National Academy of Sciences, the researchers write:

We have developed an automated system capable of large-scale reconstruction of protolanguage word forms, cognate sets, and sound change histories. The analysis of the properties of hundreds of ancient languages performed by this system goes far beyond the capabilities of any previous automated system and would require significant amounts of manual effort by linguists. Furthermore, the system is in no way restricted to applications like assessing the effects of functional load: It can be used as a tool to investigate a wide range of questions about the structure and dynamics of languages.

"Functional load" is a mid-twentieth century theory that suggests some sounds are more important than others in a language because they're used to distinguish between words that sound the same. For example, in the words "dog" and "tog," there's one important sound used to distinguish between them -- it's the voicing of the "d". Your tongue is in the same place to make both letters. The only difference is that "d" requires you to use your voice, and "t" is just expelling air. An important sound like that voicing is probably going to be preserved over time, because it's used in a lot places to distinguish between words.

Ultimately, this program could allow linguists to hear languages that haven't been spoken in millennia, reconstructing a lost world where those languages spread across the world, evolving as they went.

Over time, this program could be used for linguistic futurism, too. In a release, UC Berkeley cognitive scientist Tom Griffiths said:

Our statistical model can be used to answer scientific questions about languages over time, not only to make inferences about the past, but also to extrapolate how language might change in the future.

Perfect for time travelers. Read the full research paper in PNAS.
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References:

Westbrook, Roberto. 2013. “A New Way to Listen to Extinct Languages”. Discovery News. Posted: February 19, 2013. Available online: http://news.discovery.com/tech/gear-and-gadgets/listen-extinct-languages-130219.htm

Thursday, March 28, 2013

Why Humans Get Lost

In 1996, a ranger flying a helicopter over Death Valley, Calif., spotted a minivan in a wash near Anvil Canyon. That was ominous for several reasons: There was no road leading up to the spot, and the area wasn't passable without a four-wheel vehicle.

After investigating the vehicle, park rangers determined that four German tourists — a man, a woman, and their two sons, ages 4 and 11 — had last rented the minivan. But there was no trace of the family itself.

Their remains were not found for about 15 years, until Tom Mahood, a physicist-turned-adventurer, retraced their steps. As he recounts on his website, a series of reasonable mistakes, such as misreading the steepness of a canyon descent and being led astray by culturally confusing map landmarks, likely led to the decisions that ended in them separating, then dying in the scorching desert heat.

The story reveals how easy it is for people to become hopelessly lost in the wilderness. Humans get lost in part because we don't pay attention and have lost ancient ways of reading the environment to navigate. But humans' way-finding abilities are also less precise than the abilities of other animals.

While innate navigational ability differs, "just about everyone can get better," said Daniel Montello, a geographer and psychologist at the University of California Santa Barbara.

Ancient tools

Historically, not getting lost was a matter of life or death. One wrong turn could lead to a hyena's den or a nasty death from thirst. As a result, all indigenous cultures navigate in part by tracking the sun or the stars' positions in the sky relative to the fixed star Polaris, said Tristan Gooley, author of "The Natural Navigator" (The Experiment, 2012) and owner of naturalnavigator.com.

Those cues "are as good if not better than a compass in many situations," Gooley told LiveScience.

For instance, Polynesian seafarers track direction using ocean swells, the natural rise and fall of the water caused when a huge storm generates waves deep at sea. Because swells can linger for days, they can reliably be used to fine-tune direction, Gooley said. The Polynesians can track up to eight swells at a time, he said.

Both land and sea bear traces of long- and short-term directional cues. For instance, grass may wave in the direction of the winds on a given day, but a tree may lean toward the direction the winds blow over long periods of time, Gooley said.

Use it or lose it

Human mental-mapping stems in part from a brain region called the hippocampus, and studies suggest it can be strengthened with practice. For instance, one study found cab drivers in London have bigger and thicker hippocampi than the average person, said Colin Ellard, a psychologist at the University of Waterloo in Canada and author of the book "You Are Here" (Doubleday, 2009).

But the sense of direction may also wither with disuse. Small studies have found that using a GPS for just a few hours seems to impair people's navigational skills in the short term, Montello said. Many people get lost because they simply aren't paying attention, he added.

Animal sense

It's also true that the human sense of direction is simply less precise than that of many animals. For instance, migratory birds can use internal magnetic compasses or sonar maps to create incredibly detailed mental maps. And many animals' sense of direction is instinctual and is genetically hard-wired.

In addition, humans have faulty internal senses of direction. For instance, several studies have found that people walk in circles when blindfolded or disoriented (for instance, in an unfamiliar, heavily forested area), Ellard said. African desert ants, by contrast, can march in a straight line for miles.

"They have this prodigious ability to keep track of where they are with respect to their initial starting point," Ellard told LiveScience. "They have a very accurate internal odometer."

But while animals' sense of direction is more precise, we have a much more flexible way-finding ability, Montello said. For instance, migrating animals travel thousands of miles but usually go to specific, pre-determined locations. But humans use landmarks, directional cues, a sense of how far they've traveled, as well as myriad other cues to go vastly more places, often with no prior knowledge.

"We travel much wider and farther than a lot of other animals," Montello said.

Tricks of the trade

A few simple techniques can help avoid getting lost.

"A common way that people get lost, is the environment looks different in a different direction," Montello said.

So when forging ahead on a long trek, it's helpful to look back and take a mental photograph to visualize the area from multiple orientations, Montello said.

Paying attention to visual landmarks and using dead reckoning — tracking of their speed and orientation, are also useful, he said.
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References:

Ghose, Tia. 2013. “Why Humans Get Lost”. Discovery News. Posted: March 11, 2013. Available online: http://news.discovery.com/human/evolution/why-humans-get-lost-130312.htm

Lost Beothuk nation’s religion takes flight

The Indigenous Beothuk of Newfoundland disappeared as a culture during the early nineteenth century and had little positive interaction with Europeans before this time. As a result, very little is now known regarding Beothuk religious life and belief.

Sacred cosmology

University of Alberta researcher Todd Kristensen and his U.S. co-author Donald Holly have drawn on available ethnohistoric records, an analysis of burial sites in addition to the funerary objects themselves to offer an interpretation of Beothuk sacred cosmology that places birds at the centre of their belief system.

These birds were  at the centre of their complex religious belief system that revered the winged creatures as “spiritual messengers” that carried the souls of the dead to an “island afterlife.”

The remarkable revelations about the vanished culture, the 19th-century eclipse of which remains one of the central tragedies of Canadian history, are detailed in a paper published in the Cambridge Archaeological Journal.

Violent encounters

After Anglo-Italian explorer John Cabot’s landmark voyage to Newfoundland in 1497, the indigenous Beothuk clashed constantly with a succession of settlers and colonisers from Portugal, France and Britain in the following four centuries.

According to some reports, the Beothuk may also have been the so-called “skraelings” who had violent encounters as Norse explorers made their first contacts with indigenous Americans. By the time these sources were recorded, Skræling was the common term Norse Greenlanders used for the Thule people, the ancestors to the modern Inuit.

Once numbering as many as 5,000 people, the Beothuk population was ravaged by diseases introduced to the future Canada by European settlers. An artistically gifted Beothuk woman named Shanawdithit, the last known survivor of her people, died in St. John’s in 1829, bringing to an end a cohesive culture.

Happy Island

The new study refers to historical records that Shanawdithit once referred to a “happy island” afterworld that somehow figured prominently in the Beothuk’s belief system.

The distribution of archaeological sites that are attributed to the Little Passage complex, seems to confirm the coastal orientation of the Beothuk who followed on from this prehistoric culture. There appears to have been a direct correlation between the settlement pattern that favoured sheltered bays, inlets and archipelagos offering strategic access to a full range of resources, with birds acting as a significant part of the diet.

Sea birds such as the Arctic tern and the black guillemot and the now extinct great auk provided both “food and food for thought” for the ancient Newfoundland inhabitants.

Kristensen feels that the ongoing research is important because “there are no modern Beothuk people to say that this is is what we believed in, and this is the story that we should share.” Archaeologists become the one group of people who can tell the Beothuk story.

No other object is as closely associated with the Beothuk today as the enigmatic bone pendant. Pendants were often fashioned from caribou bones that were split, ground down into thin tabular forms and then exquisitely carved, engraved and coated with red ochre.

A connection between burials and birds

Of the 28 recorded Beothuk burial sites in Newfoundland, 11 are known to have yielded bone pendants, and numerous other burials likely housed pendants prior to extensive looting in the 19th and 20th centuries. Pendants have even been found at three suspected burial sites that lack human remains, which may represent burials in lieu of a body (which may have been lost at sea). It is obvious these well worn, repaired and deeply personal items played a major role in the life of a Beothuk individual.

Beothuk pendants come in a variety of shapes and designs and the authors suspect that many represent birds or parts of their anatomy; some bone pendants seem to represent primary wing feathers while other are clearly feet, others relate to complete, but stylised diving birds. Given that the Beothuk conceived of the afterlife as an island, it is perhaps not surprising that with only one exception, all known Beothuk burial sites occur on the coast as a suitable departure point to a distant happy island, and of the 28 recorded coastal burial sites, 22 are even located on small islands.

The Beothuk experienced birds daily and must have acquired an intimate knowledge of bird’s flying, diving and swimming as well as the cyclical nature of bird migration. Kristensen feels that the Beothuk must have incorporated this into belief systems regarding the dead – leaving for new life.

A solid manifestation of this bird cosmology are the bone pendants,which use birds to relate to the transformation between life and death. Bird pendants and even parts of birds are clearly associated with burials, which suggest connects birds to a belief in soul flight acting as spiritual messengers to carry the dead to the afterlife of the Beothuk their mysterious  ‘happy island’.
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References:

Past Horizons. 2013. “Lost Beothuk nation’s religion takes flight”. Past Horizons.. Posted: February 17, 2013. Available online: http://www.pasthorizonspr.com/index.php/archives/02/2013/lost-beothuk-nations-religion-takes-flight

Wednesday, March 27, 2013

Buddhist ruins discovered in Taklimakan desert

The ruins of a Buddhist temple dating back 1,500 years ago have been discovered in China's largest desert--the Taklimakan in Xinjiang Uygur autonomous region. The findings offer valuable research material for historians studying the development of Buddhism in China.

These historic findings shed light on the development of Buddhism in China. In total there are more than 3,000 pieces of relics. The most eye-catching are the mural paintings. They are executed in a Greco-Buddhist art style, which was seldom seen after the 6th century.

Archaeologist Dr. Wu Xinhua said, "It’s very unique. We’ve never come across such mural paintings in this area before. You can see the fusion of Western and eastern cultures alongside the spread of Buddhism in ancient China."

The treasures are all from a Buddhist temple located in the southern Taklimakan Desert. Excavation was completed in June last year. Experts believe the temple dates back to the Southern and Northern Dynasties, about 1,500 years ago.

Dr. Wu said, "The hall is the largest of its kind found in the Taklimakan Desert since the first archaeologist came to work in the area in the 20th century. The structure of the temple is very unique. We believe it is one of the earliest Buddhist temples in China."

The temple has become the point of convergence for scholars studying how Buddhism arrived in China from India, and its early development in the country.
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References:

2013. “Buddhist ruins discovered in Taklimakan desert”. CNTV. Posted: February 17, 2013. Available online: http://english.cntv.cn/program/cultureexpress/20130217/101471.shtml

Tuesday, March 26, 2013

Deja vu all over again? Cultural understanding vs. horrors of eugenics

Human Genome Project has lessons to learn, suggests anthropologist

Why is the world so full of "morons" and "degenerates" and what, if anything, can be done to fix them?

These are questions that Robert W. Sussman, PhD, a professor of anthropology in Arts & Sciences at Washington University in St. Louis, will explore Feb. 15 as he addresses the 2013 meeting of the American Association for the Advancement of Science (AAAS) in Boston, Mass. — one of the world's largest gatherings of scientific researchers.

Sussman will deliver a talk on "The Importance of the Concept of Culture to Science and Society" (http://aaas.confex.com/aaas/2013/webprogram/Paper8433.html )during a session titled The Whole of Culture: Anthropology Back on Track.

Sussman, author of Man the Hunted: Primates, Predators and Human Evolution, says that science has struggled to understand the mysteries of "less-than-human" beings since the late 1400s when the Spanish Inquisition first formalized state persecution of Jews and Muslims.

And while the horrors of Nazi Germany exposed fatal flaws in science's quest to build the master race, the ethical dilemmas posed by the science of eugenics are far from behind us.

As Sussman presents his lecture on the evolution of scientific and cultural explanations for criminality, homosexuality, drunkenness and other variances in human behavior, scientists elsewhere at the AAAS meeting will be unveiling amazing new techniques for the genetic engineering of humans — tools more powerful than a Nazi's wildest dreams.

Meanwhile, legislation currently being considered in Virginia, North Carolina and other states would provide monetary compensation for the survivors of high-minded efforts to improve the gene pool by forcibly sterilizing some 65,000 mostly poor, minority or disabled Americans. Some of these state-sponsored sterilization programs, which first became common in the 1920s, were still in place as recently as the 1970s.

As recent news reports have detailed, at least nine U.S. states, including California, Florida, Georgia, Iowa, Louisiana, Montana, Oregon, Texas and Wisconsin, still have versions of chemical castration laws on their books, usually as a penalty or "fix" for habitual child sexual predators.

And, while ongoing research suggests genetic testing may one day allow us to identify babies with gene defects that will lead to autism, there is no clear consensus on whether genetic technologies should be used to correct these deficits. As advocates of "neurodiversity" have argued, some high-functioning people with Asperger's syndrome might well prefer that no one goes meddling with their unique gene set.

For Sussman, the key starting point for all these discussions should be the understanding that while all human behaviors are driven in some way by our genetic makeup, the vast majority of individual variances result from a person's social, environmental and cultural exposure.

"The anthropological concept of culture is extremely important and often misunderstood because many of the things that are assumed to be biologically determined, like criminality or homosexuality or IQ, are really behaviorally and societally defined," says Sussman.

"The only reason they are thought to be biologically inherited is because of a misunderstanding and a lack of understanding of the anthropological concept of culture."

In his AAAS lecture, Sussman will show how primitive, quasi-scientific theories were trotted out over the centuries to justify the maltreatment of groups considered less human than the currently prevailing racial, ethnic, religious or social class.

By the early 1500s, he notes, science offered two competing theories for how Africans, Jews and Muslims came to be so inferior to Western European christians, who were considered to have been created in God's own likeness.

"The germs of racism began even before the Spanish Inquisition," Sussman explains. "Early in European history different peoples were thought of as either Pre-Adamites or as degenerates. Pre-Adamites were biologically fixed in their characteristics and could not be changed by living conditions or by education.

"Those who believed that 'others' were degenerates assumed that these peoples were born of god but could be improved by changing their habits and environment, they could be missionized. These ideas persisted until the time of Darwin and similar ideas persist even today."

Sussman traces how legitimate scientific breakthroughs, such as Mendelian genetics and Darwin's theories of evolution, were often warped and misrepresented to provide support for more politically popular concepts espoused by eugenicists.

Among the most popular pseudo-scientific books of the early 1900s were two that examined the family trees of poor rural families, the Jukes and the Kallikaks. Both books claimed to have documented how heredity had cursed the families' feeble-minded offspring, causing them to become prostitutes, drunks and delinquents and costing the government millions of dollars in expenses over their degenerate lifetimes. Their sensational stories, eerily similar to those portrayed in modern day reality television and docudramas such as "The Wild and Wonderful Whites of West Virginia," (http://www.wildandwonderfulwhites.com/ ) fanned public outrage about the societal burdens imposed by degenerates and whipped up support for sterilization programs.

Meanwhile, as hordes of immigrants streamed into America through Ellis Island, eugenicists played on anti-foreigner biases by using culturally biased IQ tests to "prove" that many of these newcomers were intellectually inferior morons, even though most failed the tests because they did not yet understand the English language.

However, in the early 1900s, some of the more blatant tenets of eugenics began to face challenges from an emerging body of scientific evidence supporting the important role that cultural experience, societal influence and environment play in shaping human behavior.

In 1911, pioneering American anthropologist Franz Boas showed that the skull shapes of some immigrant groups, then considered to be a permanent racial trait, could be changed by their new American environment within a few generations.

Boas' work, along with a re-synthesis of earlier work by Darwin and Mendel, helped build scientific support for a new and powerful anthropological concept of culture — the idea that how and what humans thought mainly was related to their life history, education, and socialization.

Human societies were not inferior or superior to one another, Sussman says, but rather were different because of their different histories.

"Boas's rejection of the traditional view was truly radical," Sussman explains. "That there were observable social differences among peoples was undeniable, but the explanation for those differences was due to the product of different histories, not differences in basic biology."

Sussman buttresses his arguments for the critical importance of culture in understanding human behavior by debunking studies that attempt to identify cultural behaviors in animals.

Monkeys and meerkats may pass along simple learned behaviors, such as the use of primitive tools, from one generation to the next, but these legacies pale in comparison to complex human cultural achievements, such as language, he contends.

Now, more than ever, says Sussman, the anthropological concept of culture must be considered a key variable in any attempt to understand human behavior, both within anthropology and in other areas, such as psychology, economics, medicine and genetic engineering, where we risk repeating the notorious ethical lapses of eugenics-driven science.

"Just as Boas trumped the biological determinism of eugenics and Nazism in the 1940s, the concept of culture should trump neo-biological determinism or genetic determinism currently," he concludes.
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References:

EurekAlert. 2013. “Deja vu all over again? Cultural understanding vs. horrors of eugenics”. EurekAlert. Posted: February 14, 2013. Available online: http://www.eurekalert.org/pub_releases/2013-02/wuis-dv021413.php

Monday, March 25, 2013

Bilingual babies know their grammar by 7 months

Babies as young as seven months can distinguish between, and begin to learn, two languages with vastly different grammatical structures, according to new research from the University of British Columbia and Université Paris Descartes.

Published today in the journal Nature Communications and presented at the 2013 Annual Meeting of the American Association for the Advancement of Science (AAAS) in Boston, the study shows that infants in bilingual environments use pitch and duration cues to discriminate between languages – such as English and Japanese – with opposite word orders.

In English, a function word comes before a content word (the dog, his hat, with friends, for example) and the duration of the content word is longer, while in Japanese or Hindi, the order is reversed, and the pitch of the content word higher.

"By as early as seven months, babies are sensitive to these differences and use these as cues to tell the languages apart," says UBC psychologist Janet Werker, co-author of the study.

Previous research by Werker and Judit Gervain, a linguist at the Université Paris Descartes and co-author of the new study, showed that babies use frequency of words in speech to discern their significance.

"For example, in English the words 'the' and 'with' come up a lot more frequently than other words – they're essentially learning by counting," says Gervain. "But babies growing up bilingual need more than that, so they develop new strategies that monolingual babies don't necessarily need to use."

"If you speak two languages at home, don't be afraid, it's not a zero-sum game," says Werker. "Your baby is very equipped to keep these languages separate and they do so in remarkable ways."
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References:

EurekAlert. 2013. “Bilingual babies know their grammar by 7 months”. EurekAlert. Posted: February 14, 2013. Available online: http://www.eurekalert.org/pub_releases/2013-02/uobc-bbk021113.php

Sunday, March 24, 2013

Fragments of stone cross lead to archaeological exploration in Scottish Highlands

Archaeologists are set to explore an enigmatic moat close to a church in a remote corner of north west Sutherland in Scotland, hoping to find evidence of early Christian practice.

The excavation at Inchnadamph will begin on 18 February. The local community history society, Historic Assynt, hopes that excavation of the ancient moated enclosed area will help to explain the origins of perplexing fragments of a stone cross found at the site.

Early ecclesiastical foundation?

Graeme Cavers, AOC Archaeology’s project manager for the dig, said:

“The Inchnadamph site is very unusual in western Sutherland, and there are a number of theories as to what the enclosure might be. The best bet is that it dates to the medieval period, as it is most similar to moated sites of the middle ages found across Scotland, but mainly in the south.

The association with the Inchnadamph cross fragments is particularly intriguing, and it is also a possibility that the site is an early ecclesiastical foundation – perhaps one of the first Christian settlements in Assynt. Getting some dating evidence for the construction will be of major significance in helping narrow down the possibilities.”

Burnt mound with surprising date

AOC Archaeology works with Historic Assynt on the Fire and Water project, which included excavation of a burnt mound at Stronechrubie, close to Inchnadamph, in October 2012. The carbon dating of charcoal at that site has revealed that the mound was used for two distinct periods – one, as was expected, in the mid bronze age, roughly three thousand years ago, and the second,very surprisingly, in the mediaeval period, about one thousand years ago. Quite what was going on in Assynt a thousand years ago therefore seems to becoming increasingly mysterious.

When did Christianity reach Assynt?

Gordon Sleight, projects leader for Historic Assynt, said, ‘The big question is whether there is a relationship between the moated site and the early Christian Cross discovered in the neighbouring churchyard. So it would be great to find evidence for the date of the creation of the moat or artefacts that give a clearer indication of what it was used for.’

One thousand years ago, Sutherland and Caithness were ruled by the Kingdom of Norway, via Sigurd, Jarl of Orkney, who converted to Christianity in 999AD. There are suggestions that the Inchnadamph cross is considerably older than that, but there is otherwise scant evidence to inform historians about when Christianity reached Assynt.

Heritage, a living part of the community

Historic Assynt’s Fire and Water project is funded by the Heritage Lottery Fund and Robert Kiln Trust. As well as the Stronchrubie excavation, the Fire and Water project has also run several other associated events including a ‘Finds Roadshow’, a ‘Music Through Time’ day and the inauguration of five heritage trails.

Colin McLean, Head of HLF Scotland, said “This is an exciting project driven by the local residents of Assynt. It demonstrates how our heritage can be a living part of a community bringing people together to learn from and enjoy their shared identity.”

Volunteers and visitors are welcome at the excavation, which will run until 22 February 2013.
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References:

Past Horizons. 2013. “Fragments of stone cross lead to archaeological exploration in Scottish Highlands”. Past Horizons. Posted: February 14, 2013. Available online: http://www.pasthorizonspr.com/index.php/archives/02/2013/fragments-of-stone-cross-lead-to-archaeological-exploration-in-scottish-highlands

Saturday, March 23, 2013

Battered Skulls Reveal Violence Among Stone Age Women

Stone Age farmers lived through routine violence, and women weren't spared from its toll, a new study finds.

The analysis discovered that up to 1 in 6 skulls exhumed in Scandinavia from the late Stone Age — between about 6,000 and 3,700 years ago — had nasty head injuries. And contrary to findings from mass gravesites of the period, women were equally likely to be victims of deadly blows, according to the study published in the February issue of the American Journal of Physical Anthropology.

Ancient pastoralists

Linda Fibiger, an archaeologist at the University of Edinburgh in Scotland, and her colleagues focused on the late Stone Age, when European hunter-gatherers had transitioned into farming or herding animals.

Some mass graves unearthed from that time contained mostly males who had died in violent conflicts. As such, researchers had thought women were spared from conflicts due to their potential childbearing value, Fibiger told LiveScience.

But looking only at the aftermath of big, bloody conflicts can obscure the day-to-day realities of Neolithic farmers.

"It would be like only looking at a war zone to assess violence," Fibiger said. "That's not going to tell you what's going on in your neighborhood."

Routine violence

To see what more humdrum days looked like for these Stone Age farmers, the team assessed 378 skulls from collections throughout Sweden and Denmark from between 3900 B.C. and 1700 B.C. They distinguished bumps due to falls or accidents from violent wounds, which might leave evidence such as an "axe-shaped hole in the skull," Fibiger said.

Nearly 10 percent of the Swedish skulls exhibited signs of violent injury, and nearly 17 percent of the Danish skulls had such wounds. Men had more nonfatal injuries, but women were just as likely as men to have lethal head wounds — which can be identified because they never healed.

That suggests these ancient herders routinely experienced violence, likely due to raids, family feuds, or other daily skirmishes with competing groups, Fibiger said.

Poor fighters

It's not clear why women were frequent victims of violence.

Domestic violence could be a factor, but proving it requires looking for repeat injuries and wounds to the ribs and torso, Fibiger said. Given that skulls and skeletons are jumbled up at these sites, and many skeletons weren't preserved, that's not possible, Fibiger said.

More likely is that women suffered fatal injuries, because they couldn't fight ferociously in raids, she told Live Science.

Men may have trained from a young age to fight, whereas women were probably tasked with child rearing.

That would have slowed them down, "because you're probably going to try and protect your children rather than being able to properly defend yourself," Fibiger said.

The findings are impressive, said Christian Meyer, an anthropology doctoral candidate at the University of Mainz in Germany, who was not involved in the study.

"It's one of the first that really looks at a really large sample size, and it draws from a larger region," Meyer said.

Analyzing so many Stone Age skulls allows researchers to quantitatively compare rates of such violence throughout Europe at the time.
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References:

Ghose, Tia. 2013. “Battered Skulls Reveal Violence Among Stone Age Women”. Live Science. Posted: February 12, 2013. Available online: http://www.livescience.com/27055-neolithic-skulls-show-violence.html

Friday, March 22, 2013

Scientists Create Automated 'Time Machine' to Reconstruct Ancient Languages

Ancient languages hold a treasure trove of information about the culture, politics and commerce of millennia past. Yet, reconstructing them to reveal clues into human history can require decades of painstaking work. Now, scientists at the University of California, Berkeley, have created an automated "time machine," of sorts, that will greatly accelerate and improve the process of reconstructing hundreds of ancestral languages.

In a compelling example of how "big data" and machine learning are beginning to make a significant impact on all facets of knowledge, researchers from UC Berkeley and the University of British Columbia have created a computer program that can rapidly reconstruct "proto-languages" -- the linguistic ancestors from which all modern languages have evolved. These earliest-known languages include Proto-Indo-European, Proto-Afroasiatic and, in this case, Proto-Austronesian, which gave rise to languages spoken in Southeast Asia, parts of continental Asia, Australasia and the Pacific.

"What excites me about this system is that it takes so many of the great ideas that linguists have had about historical reconstruction, and it automates them at a new scale: more data, more words, more languages, but less time," said Dan Klein, an associate professor of computer science at UC Berkeley and co-author of the paper published online Feb. 11 in the journal Proceedings of the National Academy of Sciences.

The research team's computational model uses probabilistic reasoning -- which explores logic and statistics to predict an outcome -- to reconstruct more than 600 Proto-Austronesian languages from an existing database of more than 140,000 words, replicating with 85 percent accuracy what linguists had done manually. While manual reconstruction is a meticulous process that can take years, this system can perform a large-scale reconstruction in a matter of days or even hours, researchers said.

Not only will this program speed up the ability of linguists to rebuild the world's proto-languages on a large scale, boosting our understanding of ancient civilizations based on their vocabularies, but it can also provide clues to how languages might change years from now.

"Our statistical model can be used to answer scientific questions about languages over time, not only to make inferences about the past, but also to extrapolate how language might change in the future," said Tom Griffiths, associate professor of psychology, director of UC Berkeley's Computational Cognitive Science Lab and another co-author of the paper.

The discovery advances UC Berkeley's mission to make sense of big data and to use new technology to document and maintain endangered languages as critical resources for preserving cultures and knowledge. For example, researchers plan to use the same computational model to reconstruct indigenous North American proto-languages.

Humans' earliest written records date back less than 6,000 years, long after the advent of many proto-languages. While archeologists can catch direct glimpses of ancient languages in written form, linguists typically use what is known as the "comparative method" to probe the past. This method establishes relationships between languages, identifying sounds that change with regularity over time to determine whether they share a common mother language.

"To understand how language changes -- which sounds are more likely to change and what they will become -- requires reconstructing and analyzing massive amounts of ancestral word forms, which is where automatic reconstructions play an important role," said Alexandre Bouchard-Côté, an assistant professor of statistics at the University of British Columbia and lead author of the study, which he started while a graduate student at UC Berkeley.

The UC Berkeley computational model is based on the established linguistic theory that words evolve along the branches of a family tree -- much like a genealogical tree -- reflecting linguistic relationships that evolve over time, with the roots and nodes representing proto-languages and the leaves representing modern languages.

Using an algorithm known as the Markov chain Monte Carlo sampler, the program sorted through sets of cognates, words in different languages that share a common sound, history and origin, to calculate the odds of which set is derived from which proto-language. At each step, it stored a hypothesized reconstruction for each cognate and each ancestral language.

"Because the sound changes and reconstructions are closely linked, our system uses them to repeatedly improve each other," Klein said. "It first fixes its predicted sound changes and deduces better reconstructions of the ancient forms. It then fixes the reconstructions and re-analyzes the sound changes. These steps are repeated, and both predictions gradually improve as the underlying structure emerges over time."
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References:

Science Daily. 2013. “Scientists Create Automated 'Time Machine' to Reconstruct Ancient Languages”. Science Daily. Posted: February 11, 2013. Available online: http://www.sciencedaily.com/releases/2013/02/130212112025.htm

Journal Reference:
1.A. Bouchard-Cote, D. Hall, T. L. Griffiths, D. Klein. Automated reconstruction of ancient languages using probabilistic models of sound change. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1204678110

Thursday, March 21, 2013

A son of Africa returns long-lost tribal treasures to land of his ancestors

I highly recommend going to the page and seeing the pictures.

Decades after they were taken away, African ceremonial masks have been returned to the communities that venerated them, thanks to an African-American family researcher who bought them through eBay.

Georgia businessman William Holland, who has been tracing his roots in West Africa for more than a decade, carried the three masks back with him last month during his latest trek to Cameroon. That's not all he was carrying: Holland also brought relics from the mid-18th century — the time when his ancestor was taken from Cameroon, loaded onto a ship, brought to Virginia and sold into slavery.

The masks made a big impression on the hundreds of Cameroonians who gathered for Holland's show-and-tell session. But the slave chains made an even bigger impression.

"When we brought the shackles out, that's when they were about to cry," he said. "They were shocked to see an authentic item that brought so much pain along with it."

Holland's frequent trips to Cameroon's Oku and Nso regions have been a learning experience for him as well as for his long-lost cousins. It took years for Holland to narrow down his approximate place of origin, based on DNA tests as well as a study of American and African pedigrees. Along the way, Holland found out that one of his ancestors was a slave who was pressed into service in the Confederate Army, and that more distant ancestors were members of royal families in Cameroon.

During the buildup to his latest trip, Holland combed through online auction sales, looking for artifacts that could help bridge the gap between the African and American history of his family. He worked with Cameroonian contacts to identify two elephant masks that were associated with the Nso people's secret rituals, plus a wooden mask with a human visage that was used by Oku families during funerals.

The masks were sold out of Africa in the 1970s or 1980s under murky circumstances, and eventually ended up in private hands. "It's almost the same thing as the slave trade," Holland observed. "Outsiders go to a middleman and ask them to get something or someone for them. 'I'm giving you guns, I'm giving you cowrie shells, I'm giving you iron bars. Bring me the people to fill this ship, and I'll give you this.' That's what it reminded me of."

Holland spent hundreds of dollars of his own money to buy the masks, as well as other items such as throwing knives, the wrist and ankle shackles and a "monkey wrench quilt" — a type of quilt that slaves used to signal each other that it was time to wrap up their tools and get ready for an escape. Then he headed for the Cameroonian towns of Kumbo, Bamenda and Oku.

"It's more than just bringing things back," he explained. "It's a history lesson about those who were taken away during the slave trade. The Cameroonians didn't receive this information in school."

Holland's trip caused a sensation in Cameroon: More than 1,000 townspeople turned out to see the American who was bringing their treasures back. In Cameroon's capital, Yaounde, Holland met the prime minister. Journalists clamored for interviews. "It was crazy," Holland said. "It was a media circus."

The chiefs of the Nso and Oku peoples, who are known as "fons," joined up to give Holland a title that combines two honored names: "Shufaay," a title that is typically given to the Nso noble next in line to the king; and "Bailack," which recognizes Holland's connection to a patriarch who came to Oku from Nso centuries ago. "No Nso son or daughter is allowed to shake hands with a Shufaay again, if they are not of the same status," Holland said. "This goes back to the ancient way of doing things."

All the attention was great — but for Holland, the most important result of the trip was the restoration of pieces of African history to their rightful places. Authorities in Kumbo are building a cultural museum that will eventually house the elephant masks and other Nso artifacts. And family members in the Oku region now have the funerary mask they were missing when their loved ones passed away.

The Fon of Oku drew a lesson from Holland's round of eBay diplomacy — a lesson that's particularly timely for the month of February, recognized in the United States as Black History Month. "He was telling people not to sell these precious things from our society," Holland recalled. "This is wrong. No matter how much money they offer, do not sell."

Holland is already planning his next trip, to the Cameroonian city of Buea in May. He'll be taking over some new history lessons to his ancestral homeland, but he's also hoping to bring back some business: Holland is planning to start up a travel business to put other African-Americans in touch with their roots, and the Africa Travel Association's annual congress in Buea seems like the perfect place for networking.

"I guess you'd call it 'historical tourism,'" Holland said. "Cameroon is really an untapped market for that."
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References:

Boyle, Alan. 2013. “A son of Africa returns long-lost tribal treasures to land of his ancestors”. NBC News Cosmic Log. Posted: February 8, 2013. Available online: http://cosmiclog.nbcnews.com/_news/2013/02/08/16900779-a-son-of-africa-returns-long-lost-tribal-treasures-to-land-of-his-ancestors

Wednesday, March 20, 2013

35 Ancient Pyramids Discovered in Sudan Necropolis

At least 35 small pyramids, along with graves, have been discovered clustered closely together at a site called Sedeinga in Sudan.

Discovered between 2009 and 2012, researchers are surprised at how densely the pyramids are concentrated. In one field season alone, in 2011, the research team discovered 13 pyramids packed into  roughly 5,381 square feet (500 square meters), or  slightly larger than an NBA basketball court.

They date back around 2,000 years to a time when a kingdom named Kush flourished in Sudan. Kush shared a border with Egypt and, later on, the Roman Empire. The desire of the kingdom's people to build pyramids was apparently influenced by Egyptian funerary architecture.

At Sedeinga, researchers say, pyramid building continued for centuries. "The density of the pyramids is huge," said researcher Vincent Francigny, a research associate with the American Museum of Natural History in New York, in an interview with LiveScience. "Because it lasted for hundreds of years they built more, more, more pyramids and after centuries they started to fill all the spaces that were still available in the necropolis."

The biggest pyramids they discovered are about 22 feet (7 meters) wide at their base with the smallest example, likely constructed for the burial of a child, being only 30 inches (750 millimeters) long. The tops of the pyramids are not attached, as the passage of time and the presence of a camel caravan route resulted in damage to the monuments. Francigny said that the tops would have been decorated with a capstone depicting either a bird or a lotus flower on top of a solar orb.

The building continued until, eventually, they ran out of room to build pyramids. "They reached a point where it was so filled with people and graves that they had to reuse the oldest one," Francigny said.

Francigny is excavation director of the French Archaeological Mission to Sedeinga, the team that made the discoveries. He and team leader Claude Rilly published an article detailing the results of their 2011 field season in the most recent edition of the journal Sudan and Nubia.

The inner circle

Among the discoveries were several pyramids designed with an inner cupola (circular structure) connected to the pyramid corners through cross-braces. Rilly and Francigny noted in their paper that the pyramid design resembles a "French Formal Garden."

Only one pyramid, outside of Sedeinga, is known to have been constructed this way, and it's a mystery why the people of Sedeinga were fond of the design. It "did not add either to the solidity or to the external aspect [appearance] of the monument," Rilly and Francigny write.

A discovery made in 2012 may provide a clue, Francigny said in the interview. "What we found this year is very intriguing," he said. "A grave of a child and it was covered by only a kind of circle, almost complete, of brick." It's possible, he said, that when pyramid building came into fashion at Sedeinga it was combined with a local circle-building tradition called tumulus construction, resulting in pyramids with circles within them.

An offering for grandma?

The graves beside the pyramids had largely been plundered, possibly in antiquity, by the time archaeologists excavated them. Researchers did find skeletal remains and, in some cases, artifacts.

One of the most interesting new finds was an offering table found by the remains of a pyramid. . It appears to depict the goddess Isis and the jackal-headed god Anubis and includes an inscription, written in Meroitic language, dedicated to a woman named "Aba-la," which may be a nickname for "grandmother," Rilly writes.

It reads in translation:

Oh Isis! Oh Osiris!
It is Aba-la.
Make her drink plentiful water;
Make her eat plentiful bread;
Make her be served a good meal.

The offering table with inscription was a final send-off for a woman, possibly a grandmother, given a pyramid burial nearly 2,000 years ago.

See 13 pictures of the site here.
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References:

Jarus, Owen. 2013. “35 Ancient Pyramids Discovered in Sudan Necropolis”. Live Science. Posted: February 6, 2013. Available online: http://www.livescience.com/26903-35-ancient-pyramids-sudan.html

Tuesday, March 19, 2013

Archeologists Unearth Alien-Like Skulls In A Mexico Cemetery


Image Credit: Cristina Garcia / INAH

Archeologists have unearthed what looks like a cone-shaped alien skull from 1,000 years ago in Mexico.

The skull, which dates from 945 A.D. to 1308 A.D., was discovered accidentally while digging an irrigation system in the northwest state of Sonora in Mexico.

Cristina Garcia Moreno, who worked on the project with Arizona State University, explained that 13 of the 25 skulls found in the Hispanic cemetery had these deformed heads.

“We don’t know why this population specifically deformed their heads,” Moreno told ABC News.

The site, known as El Cementerio, was discovered in 1999, but the team just completed their analysis of the skeletal remains last month. They plan to continue their research during the next field season. Archaeologists also discovered artifacts on the site, like pendants, nose rings and jewelry.

They said the deformation of human skulls was part of an ancient ritual that took place 1,000 years ago. The deformation was achieved by binding a person’s head between two blocks of wood to apply pressure on the skull by wrapping the wood with bands.

“Cranial deformation has been used by different societies in the world as a ritual practice, or for distinction of status within a group or to distinguish between social groups,” Moreno told ABC News. “The reason why these individuals at El Cementerio deformed their skulls is still unknown.”

The team said that many of the bones unearthed were the remains of children, leading them to believe the practice of deforming skulls “may have been inlet and dangerous.”

The Chinook of the U.S. Northwest and the Choctaw of the U.S. Southeast both were known for practicing skull deformation as well.

Moreno told ABC that people deformed their heads in Mexico because they wanted to distinguish important people, or they wanted to distinguish people from one group from another.
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References:

Rennals, Lee. 2013. "Archeologists Unearth Alien-Like Skulls In A Mexico Cemetery". RedOrbit. Posted: December 27, 2012. Available online: http://www.redorbit.com/news/science/1112754510/alien-like-skulls-unearthed-mexico-122712/

Origins of the Olive Tree Revealed

The olive was first domesticated in the Eastern Mediterranean between 8,000 and 6,000 years ago, according to new research.

The findings, published today (Feb. 5) in the journal Proceedings of the Royal Society B, are based on the genetic analysis of nearly 1,900 samples from around the Mediterranean Sea. The study reveals that domesticated olives, which are larger and juicier than wild varieties, were probably first cultivated from wild olive trees at the frontier between Turkey and Syria.

"We can say there were probably several steps, and it probably starts in the Levant," or the area that today includes Israel, Palestine, Jordan, Lebanon and Syria, said study co-author Gillaume Besnard, an archaeobotanist at the National Center for Scientific Research in France. "People selected new cultivars everywhere, but that was a secondary diversification later."

From biblical times, the olive tree has served as a symbol of sacredness, peace and unity. Archaeologists have unearthed olive pits at sites dating to about 8,000 years old. And dating as far back as 6,000 years ago, archaeologists find evidence of olive oil production in Carmel, Israel, Besnard said.

Yet exactly where the olive was first cultivated has been hotly debated.

To unravel the history of the olive tree, the team took 1,263 wild and 534 cultivated olive tree samples from throughout the Mediterranean and analyzed genetic material from the trees' chloroplasts, the green plant structures where photosynthesis takes place. Because chloroplast DNA is passed from one tree to the descendant trees that spring up around it, the DNA can reveal local changes in plant lineages, he said.

The researchers then reconstructed a genetic tree to show how the plant dispersed. The team found that the thin, small and bitter wild fruit first gave way to oil-rich, larger olives on the border between Turkey and Syria.

After that first cultivation, modern-day domesticated olives came mostly from three hotspots: the Near East (including Cyprus), the Aegean Sea and the Strait of Gibraltar. They were then gradually spread throughout the Mediterranean with the rise of civilization.

But to get a true sense of how the olive tree emerged, the researchers shouldn't just look at chloroplast DNA, said André Bervillé, a geneticist at the French National Institute for Agricultural Research, who was not involved in the study. Nuclear DNA, which is carried in the pollen, should also be analyzed, Bervillé told LiveScience.

"Pollen from the olive tree is wind-transported, so it can migrate long distances" he said.

Combining both types of DNA would allow researchers to understand both how local olive tree cultivation occurred and how more long-distance changes occurred, he said.
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References:

Ghose, Tia. 2013. “Origins of the Olive Tree Revealed”. Discovery News. Posted: February 6, 2013. Available online: http://news.discovery.com/earth/plants/olive-tree-origins-130206.htm

Monday, March 18, 2013

Genes mix faster than stories

Folk tales' 'DNA' shows that people would sooner have sex with strangers than tell their fables.

Have you heard the story of the good sister and the bad sister? When they leave home, the good sister is kind to the people and animals she meets, and is rewarded in gold. The bad sister is haughty and greedy, and is rewarded with a box of snakes.

This folk tale has hundreds of variants, and it has been passed on across Europe for centuries. But how similar your version is to mine depends not just on how far apart we live but also on how ethnically and linguistically different our cultures are, according to a new study.

If folk tales simply spread by diffusion, like ink blots in paper, one would expect to see smooth gradients in these variations as a function of distance. Instead, researchers found that language differences between cultures create significant barriers to that diffusion.

These barriers are stronger than those for the exchange of genes — a message that might be crudely expressed as: “I’ll sleep with you, but I prefer my stories to yours.”

Cultural boundaries

In the study, a team of researchers in Australia and New Zealand used the statistical tools of population genetics to investigate variations in ‘The kind and the unkind girls’ across 31 European populations, such as Armenian, Scottish, Basque and Icelandic groups. Their results appear today in the Proceedings of the Royal Society B1.

“The geographic gradients we found are similar in scale to what we see in genetics, suggesting that there may be parallel processes responsible for mixing genetic and cultural information,” says lead author Quentin Atkinson, who studies human evolution at the University of Auckland in New Zealand.

“But the mechanisms aren’t identical,” Atkinson adds. “The effect of ethnolinguistic boundaries is much stronger for the folk tales than for genes.” This fits with recent studies looking at other aspects of culture, such as song2. “Our findings support predictions that cultural variation should be more pronounced between groups than genetic variation,” says Atkinson.

“This supports the view that our cultures act almost like distinct biological species,” says Mark Pagel, an evolutionary biologist at the University of Reading, UK, who specializes in cultural transmission. “Our cultural groups draw pretty tight boundaries around themselves and can absorb genetic immigrants without absorbing their cultures.”

Atkinson and his colleagues figured that the ubiquity of folk tales would make them a good proxy for cultural exchange. “This tale is widely known, and we were able to locate a large, well-documented collection that spanned all of Europe,” says Atkinson. “For example, some stories involve two cousins or brothers rather than daughters; in others it is a daughter and servant girl.” He and his colleagues found about 700 variants in all.

“Folk tales can be transmitted all over the world,” says Hans-Jörg Uther, a folklore specialist at the University of Göttingen in Germany. “The plot can stay the same while characters and other attributes change to match the cultural traits of the region.”

Uther finds the work interesting, but says that he is “a little bit sceptical about comparing variants while neglecting their historical context and mode of performance.” He suspects that, as digital archives of folk tales become increasingly available, they will provide a valuable tool for making comparative and evolutionary studies of culture more quantitative.
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References:

Ball, Philip. 2013. “Genes mix faster than stories”. Nature. Posted: February 6, 2013. Available online: http://www.nature.com/news/genes-mix-faster-than-stories-1.12359

Journal References:
Nature - doi:10.1038/nature.2013.12359 1.Ross, R. M., Greenhill, S. J. & Atkinson, Q. D. Proc. R. Soc. B 280, 20123065 (2013). 2.Rzeszutek, T., Savage, P. E. & Brown, S. Proc. R. Soc. B 279, 1606–1612 (2012).

Sunday, March 17, 2013

Ancient Tombs Discovered Along Silk Road

Along the ancient trade route known as the Silk Road, archaeologists have unearthed 102 tombs dating back some 1,300 years — and almost half of the tombs were for infants.

The surprising discovery was made in remote western China, where construction workers digging for a hydroelectric project found the cluster of tombs. Each tomb contains wooden caskets covered in felt, inside of which are desiccated human remains, as well as copper trinkets, pottery and other items buried as sacrificial items, according to UPI.

"The cluster covers an area of 1,500 square meters (1,794 square yards) on a 20-meter high (66 feet) cliff, an unusual location for tombs," said Ai Tao from the Xinjiang Institute of Archaeology, as quoted in the Indian Times.

The tombs, which date back to the Tang Dynasty (618 to 907), also contain a number of well-preserved utensils made from gourds, some of which were placed inside the wooden caskets, the Indian Times reports.

But why so many of the tombs are for infants remains a mystery. "Further research is needed to determine why so many people from that tribe died young," Ai told UPI.

The area where the tombs were found, the Kezilesu Kirgiz Autonomous Prefecture, was an important mountain pass along the Silk Road, a network of ancient trading routes that connected the Far East with Europe.
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References:

Lallanilla, Marc. 2013. “Ancient Tombs Discovered Along Silk Road”. Live Science. Posted: February 6, 2013. Available online: http://www.livescience.com/26904-silk-road-infant-tombs-discovered.html

Saturday, March 16, 2013

Why men find it harder than women to read a person's emotions

Psychiatrists have concluded that males take longer to assess facial expressions as their brains have to work twice as hard to work out whether another person looks friendly or intelligent.

Researchers from Edinburgh University said that it confirmed the "old folk wisdom" about the abilities of both sexes to "empathise, emote and process social stimuli".

“Our findings suggest that men have developed strategies to cope with their lesser natural empathy by over-activating the parts of the brain that understand social cues,” said Prof Stephen Lawrie, who led the study.

“As this pattern is also seen in people with autism-linked conditions, it suggests we could devise new tools to help patients learn social rules and enhance their skills for engaging with other people.”

Researchers used brain scans to study an individual's reaction while several expressive faces were flashed before them.

Using magnetic resonance imaging (MRI), participants were split into three groups; women, men, and men with Asperger's syndrome, a disorder that makes understanding others more difficult.

In the study, published in PLOS One, brains were scanned as they came up with their answers and their responses were timed.

Prof Lawrie, the university’s head of psychiatry, said it was designed to give the men enough time to come up with the correct answers.

But, faced with snap decisions in real life, they might start misjudging others’ thoughts.

"We chose relatively strong expressions so slowish blokes could do it," said Prof Lawrie.

"If we had been more subtle, some of the men might have started going wrong."

The MRI scans suggested which areas of the brain were activated when the volunteers were asked to decide whether the faces they were shown looked trustworthy, approachable or intelligent.

Both groups of men experienced increased blood flow to the part of the brain responsible for social function.

They concluded that women reacted more quickly than men to the feelings on show, and autistic men had to work hardest to "read" the emotions.

Prof Lawrie said that for men to achieve the same results as women in social situations, they probably had to think harder.
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References:

Telegraph Reporters. 2013. “Why men find it harder than women to read a person's emotions”. The Telegraph. Posted: February 5, 2013. Available online: http://www.telegraph.co.uk/science/science-news/9849265/Why-men-find-it-harder-than-women-to-read-a-persons-emotions.html

Friday, March 15, 2013

Princesses of the Mediterranean in the dawn of history

The Museum of Cycladic Art (MCA) in Athens, Greece is presenting a major new archaeological exhibition entitled ‘Princesses’ of the Mediterranean in the dawn of History.

A new insight

The exhibition is curated by the MCA’s Director Professor Nicholas Stampolidis, in collaboration with Dr Mimika Giannopoulou and presents 24 examples of ‘princesses’ from Greece, Cyprus, Southern Italy, and Etruria from between  1,000 to 500 BC, displaying over 500 artefacts to shine new insight into the women of the Archaic Mediterranean.

Royal ladies or princesses; priestesses or healers; women of authority; are all women who stood apart from the rest who either accepted and adopted cultural traits of different societies or of the men they married in their homeland.

Through their stories, one can perceive how women played a contributing role in broadening the cultural horizons of their time, including their involvement in the development of the archaic Mediterranean culture.

This exhibition presents real women rather than mythical figures; women who were born, lived and were very much of flesh and bone.

Lifting a veil on women of antiquity

When considered with tomb and burial typologies, funerary customs, and, above all, the grave goods such as garments and jewellery buried with them – whether chosen by the deceased in life, or provided after their passing by loved ones to take to Persephone’s meadow – these remains can potentially help ‘resuscitate’ them by lifting the veils of time to see their likeness, however faintly, as far as archaeological thinking and interpretation permits.

The term ‘princesses’ in the title does not necessarily refer to real princesses of a royal or princely lineage, although these are also present. Because the regimes, roles, and possessions of the persons of power and prestige differed from one another in the eastern and central Mediterranean during the long interval covered by this exhibition (1,000-500 BC), the terms ‘king/queen’ and ‘prince/princess’ cannot be defined unequivocally. Therefore, the terms ‘prince/princess’ (from the Latin princeps) are used here in a broader sense to describe someone eminent in their community for reasons such as lineage (family), prestige, or wealth.

The Lady of Lefkadi in Euboea, the wealthy Athenian Lady from the Areopagus, the famous Picenean queen from Sirolo-Numana near modern Ancone, burials from Verucchio and Basilicata in Italy, from Eleutherna in Crete, from Sindos in Thessaloniki are only a few examples of the exhibition which dazzles with its wealth of objects and personality

The assembled artefacts

The various assemblages comprise bronze vases, bronze and iron implements, glass and faïence objects, terracotta, bronze, and ivory figurines.

There is a wealth of jewellery: gold, silver and bronze breastplates, belts, bracelets and armbands, earrings, finger rings, hair pins, and necklaces; bronze, iron, or silver fibulae; beads of faïence, amber, precious and semi-precious stones, such as amethyst, carnelian, rock crystal, and Egyptian blue; scarabs made of various materials; gold masks; various pins and pendants.

The jewellery displays a vast array of fine gold and silverwork techniques, such as pierced work, granulation, embossing, chasing, and decorative wire, which illustrate a world of high art and wealth. The famous wooden throne of a princess from a tomb at Verruchio (Italy) completes the display.

In an attempt to give a Mediterranean dimension to the role of women in the dawn of history, from the 10th century BCE to the Archaic period (6th century BCE), 24 assemblages of grave goods associated with women from Greece (Attica, Euboea, Macedonia, Crete), Cyprus, Southern Italy, and Etruria are on display.

Analysis of these specific burials reveals how, concentrations of grave gifts and the similarities in burial customs, establish a strong ideological connection and a collective social dimension between countries and civilizations; it appears that these women, who held high status positions in their societies, were carriers of cultural and social information.

The exhibition’s strength lies in the selection of artefacts belonging to real women from the past, rather than mythical figures such as Helen of Troy. A genuine, tangible dimension is provided, where specific women are shown to be the active protagonists in the society and consequently, the human element plays a definitive role. The opportunity is afforded to discuss the interpretative issues and approaches of a woman’s role in the Early Iron Age societies.

The exhibition will run until 10 April, 2013.
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References:

Past Horizons. 2013. “Princesses of the Mediterranean in the dawn of history”. Past Horizons. Posted: February 5, 2013. Available online: http://www.pasthorizonspr.com/index.php/archives/02/2013/princesses-of-the-mediterranean-in-the-dawn-of-history

Thursday, March 14, 2013

Scientists found a 600-year-old coin from China on the Kenyan island of Manda that proves China and East Africa traded decades before European explorers set sail to east Africa, effectively rewriting the history of international trading, according to reports.

A joint expedition of scientists led by Dr. Chapurukha Kusimba of The Field Museum and Sloan Williams of the University of Illinois at Chicago found the 600-year-old Chinese coin, a small disk of copper and silver with a square hole in the center so it could be worn on a belt. He said it was issued by Emperor Yongle of China who reigned from 1403 to 1425 during the Ming Dynasty. Yongle, who began construction of China's Forbidden City, was interested in political and trade missions to East Africa and sent Admiral Zheng He, also known as Cheng Ho, to explore its shores.

"Zheng He was, in many ways, the Christopher Columbus of China," said Kusimba, Curator of African Anthropology at The Field Museum. "It's wonderful to have a coin that may ultimately prove he came to Kenya."

"This finding is significant. We know Africa has always been connected to the rest of the world, but this coin opens a discussion about the relationship between China and Indian Ocean nations," Kusimba added.

That relationship between China and East Africa ceased soon after Yongle's death when successive Chinese rulers banned foreign expeditions, which paved the way for European explorers to dominate the Age of Discovery and expand their countries' empires. While the Portuguese were the first Europeans to explore current-day Kenya with Vasco da Gama having visited Mombasa, a key port for ivory, in 1498, modern European exploration of Kenya didn't start until 1844 when two German missionaries, Johan Ludwig Krapf and Joahnnes Rebmann came in an attempt to introduce Christianity.

The island of Manda, off the Kenyan northern coast, was home to an advanced civilization from about 200AD to 1430AD, when it was abandoned and never inhabited again. Nevertheless, trade played an important role in the island's development, something the 600-year-old coin found may show.

Scientists from Kenya, Pennsylvania and Ohio also participated in the expedition, finding human remains and other artifacts predating the coin.
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References:

Van Hoven, Jason. 2013. "600-Year-Old Coin Found: Finding Proves China, East Africa Traded Before Europe Explored". International Science Times. Posted: March 14, 2013. Available online: http://www.isciencetimes.com/articles/4697/20130314/600-year-old-coin-found-china-manda.htm

New signs of pre-Viking life on the Faroe Islands

The earliest traces of human life on the Faroe Islands date back to the Viking era. But new pollen analyses suggest that people, and perhaps even agriculture, existed on the islands long before the Vikings arrived.

It has long been speculated that Irish monks may have migrated north to the Faroe Islands long before the Vikings arrived there.

But despite the tireless efforts of many scientists, nothing has yet been found which can prove that people lived on the Faroes before the time around year 800 AD. Until now.

Cereal pollen indicates early farming on the Faroe Islands

Over the past few years, scientists from Aberdeen University in Scotland have found something in early Faroese pollen samples that gives them a reason to rethink Faroese prehistory: cereal pollen.

But does finding flower dust from domesticated plants actually prove that anyone lived on the Faroes several centuries before the Vikings arrived there? And that they were farmers?

The answer is maybe. The researchers are sweating over soil samples and archaeological finds to unravel the mystery, but it’s not an easy task.

Kevin Edwards, a professor of physical geography and archaeology at Aberdeen University, tells ScienceNordic about their work:

”One of the main problems with cereal pollen is that it is produced in tiny quantities. Cereal pollen grains are also very large, and that means they don’t spread far with the wind. That’s why it’s so important to find it.”

Scientists want better samples

They have now found cereal pollen in the early samples from the Faroe Islands. There’s just one problem, though: the soil where they found the cereal pollen is far from ideal for accurate pollen analysis:

“It’s problematic that the sites where we found cereal pollen aren’t very good,” says Edwards. “It’s likely that the soil has been cluttered up, partly as a result of soil erosion, where soil from fields on nearby hillsides has fallen down into the low-lying peat bogs.”

Since peat bogs are the sites where the researchers can find samples of preserved pollen, the British research team is very keen to find samples from moors, so they can be sure that there is no clutter in the soil layers.

Now scientists will find cereal pollen if it’s there

In the meantime, they have come up with a way to make it easier to study large amounts of data and find the important cereal pollen – if it’s there to be found at all.

“Normally when you study pollen samples, you magnify them 500 times in a microscope,” says Edwards.

“Then you’ll get a clear view of it all – not only cereal pollen but also pollen from trees and herbs. But since cereal pollen is far larger than the other types of pollen, we can identify them using only 100x magnification.”

He explains that he and his colleagues first do the normal pollen counts with 500x magnification to get an idea of which plants were growing in the area, so they can figure out what the landscape looked like.

They then set the microscope to 100x magnification and go through numerous samples, this time scanning only for the large cereal pollen.

That way they minimise the risk of leaving something out.

Takes forever to count large amounts of pollen

Since even the tiniest samples contain large amounts of pollen, the scientists don’t need to go through vast amounts of material to get a general idea of the appearance of the landscape.

This means that the rare cereal pollen can escape if the researchers are not on their guard, he explains, using an example from the Shetland Islands, located just south of the Faroes:

”On the Shetland Islands we examined an area where the conventional methods did not reveal any traces of local agriculture. But we had archaeological evidence that grains were processed there. So the theory was that the grains were grown at more suitable sites on the islands and subsequently transported to the area which we examined,” he says.

”But with our low-magnification method we could study far more samples. And once we had done that, more cereal pollen popped up. This is how we documented that agriculture was practiced locally, all the way from the Bronze Age right up to the Viking period and beyond.”

Perhaps there really were people and agriculture on the Faroe Islands before the arrival of the Vikings. The pollen finds would suggest so, but further studies and improved samples are required for a conclusive answer to that.
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References:

Jensen, Tania Lousdal. 2013. “New signs of pre-Viking life on the Faroe Islands”. Science Nordic. Posted: January 28, 2013. Available online: http://sciencenordic.com/new-signs-pre-viking-life-faroe-islands

Wednesday, March 13, 2013

Human brain is divided on fear and panic

New study contends different areas of brain responsible for external versus internal threats

When doctors at the University of Iowa prepared a patient to inhale a panic-inducing dose of carbon dioxide, she was fearless. But within seconds of breathing in the mixture, she cried for help, overwhelmed by the sensation that she was suffocating.

The patient, a woman in her 40s known as SM, has an extremely rare condition called Urbach-Wiethe disease that has caused extensive damage to the amygdala, an almond-shaped area in the brain long known for its role in fear. She had not felt terror since getting the disease when she was an adolescent.

In a paper published online Feb. 3 in the journal Nature Neuroscience, the UI team provides proof that the amygdala is not the only gatekeeper of fear in the human mind. Other regions—such as the brainstem, diencephalon, or insular cortex—could sense the body's most primal inner signals of danger when basic survival is threatened.

"This research says panic, or intense fear, is induced somewhere outside of the amygdala," says John Wemmie, associate professor of psychiatry at the UI and senior author on the paper. "This could be a fundamental part of explaining why people have panic attacks."

If true, the newly discovered pathways could become targets for treating panic attacks, post-traumatic stress syndrome, and other anxiety-related conditions caused by a swirl of internal emotional triggers.

"Our findings can shed light on how a normal response can lead to a disorder, and also on potential treatment mechanisms," says Daniel Tranel, professor of neurology and psychology at the UI and a corresponding author on the paper.

Decades of research have shown the amygdala plays a central role in generating fear in response to external threats. Indeed, UI researchers have worked for years with SM, and noted her absence of fear when she was confronted with snakes, spiders, horror movies, haunted houses, and other external threats, including an incident where she was held up at knife point. But her response to internal threats had never been explored.

The UI team decided to test SM and two other amygdala-damaged patients with a well-known internally generated threat. In this case, they asked the participants, all females, to inhale a gas mixture containing 35 percent carbon dioxide, one of the most commonly used experiments in the laboratory for inducing a brief bout of panic that lasts for about 30 seconds to a minute. The patients took one deep breath of the gas, and quickly had the classic panic-stricken response expected from those without brain damage: They gasped for air, their heart rate shot up, they became distressed, and they tried to rip off their inhalation masks. Afterward, they recounted sensations that to them were completely novel, describing them as "panic."

"They were scared for their lives," says first author Justin Feinstein, a clinical neuropsychologist who earned his doctorate at the UI last year.

Wemmie had looked at how mice responded to fear, publishing a paper in the journal Cell in 2009 showing that the amygdala can directly detect carbon dioxide to produce fear. He expected to find the same pattern with humans.

"We were completely surprised when the patients had a panic attack," says Wemmie, also a faculty member in the Iowa Neuroscience Graduate Program.

By contrast, only three of 12 healthy participants panicked—a rate similar to adults with no history of panic attacks. Notably, none of the three patients with amygdala damage has a history of panic attacks. The higher rate of carbon dioxide-induced panic in the patients suggests that an intact amygdala may normally inhibit panic.

Interestingly, the amygdala-damaged patients had no fear leading up to the test, unlike the healthy participants, many who began sweating and whose heart rates rose just before inhaling the carbon dioxide. That, of course, was consistent with the notion that the amygdala detects danger in the external environment and physiologically prepares the organism to confront the threat.

"Information from the outside world gets filtered through the amygdala in order to generate fear," Feinstein says. "On the other hand, signs of danger arising from inside the body can provoke a very primal form of fear, even in the absence of a functioning amygdala."
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References:

EurekAlert. 2013. “Human brain is divided on fear and panic”. EurekAlert. Posted: February 4, 2013. Available online: http://www.eurekalert.org/pub_releases/2013-02/uoi-hbi020413.php

Tuesday, March 12, 2013

Ancient idols unearthed

Workers at construction site 40 km north of Chennai come across rare, 8th century artefacts; archaeologists say this is the first Pallavan-era finding within city limits in recent times

Little did the villagers in Kattupalli near Minjur, some 40 km north of Chennai, realise that digging a pit to earn Rs. 180 a day would lead to an important archaeological discovery and the unearthing of a 1,200-year-old Pallava period structure — the first such finding within city limits in recent times.

On Thursday evening when the labourers were hard at work on a construction site, their crowbars hit stone. After carefully displacing the earth around it, they found a small, open brick structure, within which was a granite Shiva lingam and idols of goddess Parvathy and Chandikeswarar, Lord Shiva’s attendant.

State department archaeologists, who arrived at the site, said the idols were found at a depth of eight feet. They added that the idols were possibly part of an ancient temple, built during the late Pallava era in 8th century CE.

Up until now, only Chola-era structures have been found in and around the city, in places such as Thirupalivanam, Minjur and Pulicat. “These findings are unique because the Chandikeswarar idol and the brick structure it was found in both belong to the Pallava era. The idols are intact and highly decorative,” said former deputy director of the State archaeology department, K. Sridharan.

Archaeologists said the idols’ unique features included the floral decorations beneath the Shiva lingam and the stylistic features of the Chandikeswarar idol. They noted that the Shiva lingam and the Parvarthy idol were around 400 years old, sculpted during the Vijayanagar period. They also pointed out that the Chandikeswarar idol had typical Pallava-period features such as the palm leaf-shaped head gear and large earrings.

“The size of the brick used in the structure will help determine the exact period the structure belongs to, as large bricks will indicate it belongs to the Pallava period. In the Sanagma and Chola era, regular-sized bricks were used,” said a senior archaeologist.

The workers were digging on an open plot of land, in order to lay a concrete foundation, when their tools struck the Shiva lingam. They informed panchayat and revenue officials of Ponneri taluk, as well as the police. As of now, the idols have been left at the site with security personnel to guard them until further orders from the district collectorate.

“The findings and the area will be handed over to a special team from the archaeology department once we get a communication from the collectorate,” said Ponneri tahsildar, Jagir Saleem.
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References:

Madhavan, D. 2013. “Ancient idols unearthed”. The Hindu. Posted: February 2, 2013. Available online: http://www.thehindu.com/news/cities/chennai/ancient-idols-unearthed/article4369814.ece

Monday, March 11, 2013

Tiwanaku: Pre-Incan Civilization in the Andes

Located in Bolivia, near Lake Titicaca, the ancient city of Tiwanaku was built almost 13,000 feet (4,000 meters) above sea level, making it one of the highest urban centers ever constructed.

Surrounded, in large part, by mountains and hills, the city reached its peak between roughly A.D. 500 and A.D. 1000, growing to encompass an area of more than two square miles (six square kilometers), organized in a grid plan. Only a small portion of the city has been excavated. Population estimates vary but at its peak Tiwanaku appears to have had at least 10,000 people living in it.

Although its inhabitants didn’t develop a writing system, and its ancient name is unknown, archaeological remains indicate that the city’s cultural and political influence was felt across the southern Andes stretching into modern-day Peru, Chile and Argentina.

Today, with a modern-day town located nearby, Tiwanaku is a great ruin. “Massive, stone-faced earthen mounds rise from the plain; nearby are great rectangular platforms and sunken courts with beautiful cut-stone masonry,” writes Denver Art Museum curator Margaret Young-Sánchez in her book "Tiwanaku: Ancestors of the Inca" (University of Nebraska Press, 2004).

Origins

It isn’t known when settlement at Tiwanaku began, but Young-Sánchez notes in her book that people in the Lake Titicaca area started settling permanently around 4,000 years ago.

She notes that by this time llamas (used as pack animals), alpacas (prized for their fur) and camelids had all been domesticated. In addition “farmers learned to cultivate hardy, frost-resistant crops like tubers and quinoa, watered by natural rainfall and water channeled from the mountain slopes,” Young-Sánchez writes. A millennium later these adaptations had been enhanced by “raised-field agriculture” a technique which “involves creating artificially raised planting mounds separated by canals of water.”

These adaptations enabled the development of larger and more complex settlements, one of which, Tiwanaku, would come to dominate the region.

“Why Tiwanaku? To varying degrees, environmental shift, changing trade routes, competitive political practices, and a vibrant ritual cult each played a role,” writes Vanderbilt University professor John Wayne Janusek in his book "Ancient Tiwanaku" (Cambridge University Press, 2008). “Ongoing research suggests that Tiwanaku’s rise and initial expansion were grounded more profoundly in consensus and cultural affiliation than coercion or militarism.”

The city

Field Museum researcher Patrick Ryan Williams and members of his team note in a 2007 journal article that archaeological excavations reveal that the people of Tiwanaku “maintained a dense urban population residing in well-defined, spatially segregated neighborhoods, or barrios, bounded by massive adobe compound walls.”

These “residential neighborhoods were characterized by multiple clusters of domestic structures (e.g., kitchens, sleeping quarters, storage facilities), some of which were apparently organized around a small private patio,” they add, with the inhabitants of these clusters appearing to have had “access to larger, shared outdoor plaza areas utilized for communal ceremonial events.”

The researchers are careful to add that no residential neighborhood at Tiwanaku has been completely excavated or mapped. However, one area that archaeologists have explored considerably is the city center, which contains a number of monumental structures. It’s an area, Young-Sánchez writes, “which was surrounded by an artificial moat ...”

Sunken Temple and Kalasasaya

The area surrounded by the moat contains a number of structures that appear to be of religious importance.

Janusek writes that the earliest structure appears to be the “Sunken Temple,” a small building that is descended to by way of a staircase on the south. After descending the stairs, stone monoliths can be seen in the center of the room. They depict “what were most likely the more ancient and powerful mythical ancestors of the collective communities.”

In addition, the walls of the sunken temple were decorated with the images of “deity-like beings with impassive faces and elaborate headdresses,” Janusek writes, adding that others “appear to represent skulls with desiccated skin and sunken eye sockets, and still others appear to be wailing phantasms like the banshees of Irish lore.”

Researchers Brian Bauer and Charles Stanish note that the Sunken Temple is square and about 27 meters (89 feet) long on each side. (From the book "Ritual and Pilgrimage in the Ancient Andes: The Islands of the Sun and the Moon," University of Texas Press, 2001).

Adjacent to the Sunken Temple is a platform complex known as the “Kalasasaya,” which Bauer and Stanish writes measures 120 meters by 130 meters (393 feet by 427 feet).

Janusek notes that this platform was gradually expanded and modified over time and was built over an earlier residential complex. “In building the Kalasasaya over this residence, which may have been home to some of Tiwanaku’s high-status founders, those in charge sought to position themselves as legitimate inheritors of Tiwanaku’s early ritual prestige.”

Akapana

Also in the area surrounded by the moat was what Bauer and Stanish call an “artificial pyramid” known at the Akapana. “This monumental construction measured approximately 200 by 250 meters (656 feet by 820 feet) at its base and was more than 16.5 meters (54 feet) high,” they write, noting that it had six stone terraces.

“The Akapana was by far the largest construction at Tiwanaku and was most certainly one of the principal political and sacred areas of the capital.”

University of Chicago professor Alan Kolata writes in a chapter of Young-Sánchez’s book that when archaeologists excavated the northwest portion of the pyramid they came across the skeletons of 21 people, who may be from groups Tiwanaku conquered. Found with llama bones and polychrome ceramics “several of the skeletons bore evidence of deep cut marks and compression fractures that could only have been produced by forceful blows,” Kolata writes, this hacking could have taken place before or shortly after death.

“Speaking less delicately, these people had been literally hacked apart with a heavy blade before being buried at the base of the temple.”

Pumapunku

Outside of the moat area, and located to the southwest, is a massive, unfinished, platform known as the Pumapunku. “The main platform was extensive, measuring over a half-kilometer (over 1600 feet) east-west and consisting of superimposed terraces that were roughly T-shape in plan,” writes Janusek in his book.

The main entranceway was on the west side. “One moved up the stairway through stone portals, some covered with lintels carved as totora reed bundles and into a narrow, walled, passage” Janusek writes. This passage then led to an “inner courtyard” with a “sunken paved patio.”

Janusek notes that water seems to have played a central role in the rites that took place on the platform. The Choquepacha spring is located southwest of the structure with stone conduits built around it indicating “the remains of an elaborate construction.”

Decline and rebirth

Around A.D. 1000, Tiwanaku fell into decline and the city was eventually abandoned. It collapsed around the same time the Wari culture, based to the west in Peru, also fell. The timing has led scientists to wonder whether environmental change in the Andes played a role in felling both civilizations.

But while Tiwanaku became abandoned, its memory lived on in the mythology of the people of the Andes.

“Even after its abandonment, Tiwanaku continued to be an important religious site for the local people,” writes UCLA archaeologist Alexei Vranich in an online "Archaeology" magazine article. It later became incorporated into Inca mythology as the birthplace of mankind, Vranich writes, and the Inca built their own structures alongside the ruins.
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References:

Jarus, Owen. 2013. “Tiwanaku: Pre-Incan Civilization in the Andes”. Live Science. Posted: February 1, 2013. Available online: http://www.livescience.com/26792-tiwanaku.html

Sunday, March 10, 2013

Aztec conquest altered genetics among early Mexico inhabitants, new DNA study shows

For centuries, the fate of the original Otomí inhabitants of Xaltocan, the capital of a pre-Aztec Mexican city-state, has remained unknown. Researchers have long wondered whether they assimilated with the Aztecs or abandoned the town altogether.

According to new anthropological research from The University of Texas at Austin, Wichita State University and Washington State University, the answers may lie in DNA. Following this line of evidence, the researchers theorize that some original Otomies, possibly elite rulers, may have fled the town. Their exodus may have led to the reorganization of the original residents within Xaltocan, or to the influx of new residents, who may have intermarried with the Otomí population.

Using ancient DNA (aDNA) sampling, Jaime Mata-Míguez, an anthropology graduate student and lead author of the study, tracked the biological comings and goings of the Otomí people following the incorporation of Xaltocan into the Aztec empire. The study, published in American Journal of Physical Anthropology, is the first to provide genetic evidence for the anthropological cold case.

Learning more about changes in the size, composition, and structure of past populations helps anthropologists understand the impact of historical events, including imperial conquest, colonization, and migration, Mata-Míguez says. The case of Xaltocan is extremely valuable because it provides insight into the effects of Aztec imperialism on Mesoamerican populations.

Historical documents suggest that residents fled Xaltocan in 1395 AD, and that the Aztec ruler sent taxpayers to resettle the site in 1435 AD. Yet archaeological evidence indicates some degree of population stability across the imperial transition, deepening the mystery. Recently unearthed human remains from before and after the Aztec conquest at Xaltocan provide the rare opportunity to examine this genetic transition.

As part of the study, Mata-Míguez and his colleagues sampled mitochondrial aDNA from 25 bodies recovered from patios outside excavated houses in Xaltocan. They found that the pre-conquest maternal aDNA did not match those of the post-conquest era. These results are consistent with the idea that the Aztec conquest of Xaltocan had a significant genetic impact on the town.

Mata-Míguez suggests that long-distance trade, population movement and the reorganization of many conquered populations caused by Aztec imperialism could have caused similar genetic shifts in other regions of Mexico as well.

In focusing on mitochondrial DNA, this study only traced the history of maternal genetic lines at Xaltocan. Future aDNA analyses will be needed to clarify the extent and underlying causes of the genetic shift, but this study suggests that Aztec imperialism may have significantly altered at least some Xaltocan households.
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References:

EurekAlert. 2013. “Aztec conquest altered genetics among early Mexico inhabitants, new DNA study shows”. EurekAlert. Posted: January 30, 2013. Available online: http://www.eurekalert.org/pub_releases/2013-01/uota-aca013013.php