Saturday, June 30, 2012

Robot learns language through 'conversation' with people

Robot moves from babbling to wordforms after a few minutes of interaction

A robot analogous to a child between 6 and 14 months old can develop rudimentary linguistic skills through interaction with a human participant, as reported June 13 in the open access journal PLoS ONE.

By engaging in a few minutes of "conversation" with humans, in which the participants were instructed to speak to the robot as if it were a small child, the robot moved from random syllabic babble to producing some salient wordforms, the names of simple shapes and colors. The participants were not researchers involved in the project, and were asked to use their own words, rather than any prescribed lines. The researchers, led by Caroline Lyon of the University of Hertfordshire, suggest that this work may be useful for understanding language acquisition in humans. "It is known that infants are sensitive to the frequency of sounds in speech, and these experiments show how this sensitivity can be modelled and contribute to the learning of word forms by a robot."

EurekAlert. 2012. "Robot learns language through 'conversation' with people". EurekAlert. Posted: June 13, 2012. Available online:

Friday, June 29, 2012

Can a Law Save a Language?

Authorities on the island of Java have mandated speaking a little of the local language every week. Will this keep the dreaded English invasion at bay, and does the local tongue even need the protection?

In late May, the province of Central Java, Indonesia, passed a law requiring residents to use the regional tongue, Javanese, once a week. The law is symbolic and probably unenforceable—“I swear officer, I yelled at my mother in Javanese this very morning”—but addresses what a local councillor called “a tendency for many Javanese people not to use Javanese in their daily lives.” Why is the government panicking over how its people talk, and why should we care?

If Javanese is dying, it’s hard to detect by the usual means—counting how many people use it. The language’s 75 million speakers, according to a UCLA project that tracks such things, outnumber those who converse in Polish or Korean. And in a country with deep Internet penetration, Javanese also has a vast digital footprint. Just ask SpongeBob.

In interviews with local press, the councillor advocating the bill argues that the threat to Javanese isn’t the nation’s more widely spoken tongue, Indonesian, but English. Useful for modern tasks like finding office work in nearby Australia, reading premed texts and The Hunger Games in their original versions, or collecting foreign updates on the Jakarta Lady Gaga controversy, English is the language of the future to young Javanese. Javanese feels like the past: the language grandma uses to write recipes your Facebook friends abroad would find iffy. So claim the law’s advocates.

Are they right? Regions elsewhere, notably Quebec in Canada and Catalonia in Spain, have been debating regional language rights for decades. And some nominally English-speaking nations, like Ireland and New Zealand, have legal requirements dating to their founding to promote indigenous tongues, Gaelic and Maori respectively. What’s far less studied, though, and what the Javanese experiment could show, is whether a region like Central Java can successfully legislate its language’s resistance to globalization.

And what happens when the issue arrives in a place with even harder linguistic politics—like America. Pass a law requiring Spanish Saturdays in Salinas, California (where three out of four residents are of Latino heritage) or Vietnamese Wednesday in Westminster (an LA suburb where 40 percent of residents are Vietnamese) and we’ll see you at the Supreme Court in a couple of years.

Despite its own speakers treating it as fragile, Javanese does not show up on UNESCO’s list of endangered languages. One hundred and forty-six other languages from Indonesia, however, do appear on that list. Only two are on Java despite it being the most populous island in the Indonesian archipelago. The rest hail from small communities on lesser-populated islands, and face problems from shrinking populations, not encroaching media. So where’s the law requiring people to speak Budong-Budong?

Herman, Marc. 2012. "Can a Law Save a Language?". Pacific Standard. Posted: June 11, 2012. Available online:

Thursday, June 28, 2012

China Unearths Over 100 New Terracotta Warriors

The life-size figures were excavated near the tomb of China's first emperor.

Chinese archaeologists have unearthed 110 new terracotta warriors that laid buried for centuries, an official said Monday, part of the famed army built to guard the tomb of China's first emperor.

The life-size figures were excavated near the Qin Emperor's mausoleum in China's northern Xi'an city over the course of three years, and archaeologists also uncovered 12 pottery horses, parts of chariots, weapons and tools.

"The... excavation on the 200-square-metre (2,152-square-feet) site has found a total of 110 terracotta figurines," Shen Maosheng from the Qin Shihuang Terracotta Warriors and Horses Museum -- which oversees the tomb -- told AFP.

"The most significant discovery this time around is that the relics that were found were well-preserved and colourfully painted," Shen, deputy head of the museum's archaeology department, said.

He added that archaeologists had pinpointed the location of another 11 warriors but had yet to unearth them.

The discovery is the latest in China's cultural sector, after experts found that the Great Wall of China -- which like the Terracotta Army is a UNESCO World Heritage site -- was much longer than previously thought.

Shen said experts had expected the colours on some of the warriors and wares uncovered at the site to have faded over the centuries, and were surprised to see how well preserved they still were.

The finds also included a shield that was reportedly used by soldiers in the Qin Dynasty (221-206 BC), with red, green and white geometric patterns.

Qin Shihuang -- the Qin emperor who had the army built -- presided over the unification of China in 221 BC and is seen as the first emperor of the nation.

The ancient terracotta army was discovered in 1974 by a peasant digging a well. It represents one of the greatest archaeological finds of modern times, and was listed as a World Heritage Site in 1987.

The news comes after a five-year archaeological survey found the Great Wall of China was more than double the previously estimated length.

The survey -- released to the public last week -- found the wall was 21,196 kilometres (13,170 miles) long, compared to an official 2009 figure of 8,851 kilometres.

Beijing authorities on Saturday also reiterated plans to open two new sections of the Great Wall to tourists and expand two other existing areas to help meet booming demand.

Discovery News. 2012. "China Unearths Over 100 New Terracotta Warriors". Discovery News. Posted: June 11, 2012. Available online:

Wednesday, June 27, 2012

Educators once opposed raising bilingual children. Experts now say it’s beneficial.

When I was a baby, my mother gazed down at me in her hospital bed and did something that would permanently change the way my brain developed. Something that would make me better at learning, multi-tasking and solving problems. Eventually, it might even protect my brain against the ravages of old age. Her trick? She started speaking to me in French.

At the time, my mother had no idea that her actions would give me a cognitive boost. She is French and my father English, and they simply felt it made sense to raise me and my brothers as bilingual. Yet a mass of research has emerged to suggest that speaking two languages while growing up may profoundly affect the way I think.

Cognitive enhancement is just the start. According to some studies, my memories, my values, even my personality may change depending on which language I happen to be speaking. It is almost as though the bilingual brain houses two separate minds. All of which highlights the fundamental role of language in human thought. “Bilingualism is quite an extraordinary microscope into the human brain,” says cognitive neuroscientist Laura Ann Petitto of Gallaudet University.

The image of bilingualism has not always been this rosy. For many parents, the decision to raise children speaking two languages was controversial. Since at least the 19th century, educators warned that it would confuse the child, making him unable to learn either language properly. At best, they thought, the child would become a jack-of-all-trades and master of none. At worst, they suspected it might hinder other aspects of development, resulting in a lower IQ.

These days, such fears seem unjustified. True, bilingual people tend to have slightly smaller vocabularies in each language than their monolingual peers, and they are sometimes slower to reach for the right word when naming objects. But a key study in the 1962 by Elizabeth Peal and Wallace Lambert at McGill University in Montreal found that the ability to speak two languages does not stunt overall development. On the contrary, when controlling for other factors that might also affect performance, such as socioeconomic status and education, they found that bilinguals outperformed monolinguals in 15 verbal and nonverbal tests.

Although a trickle of research into the benefits of bilingualism followed that study, it is only within the past few years that bilingualism has received a lot of attention.

In part, the renewed interest comes from recent technological developments in neuroscience, such as functional near-infrared spectroscopy (fNIRS), a form of brain imaging that can peer inside the brains of babies as they sit on their parents’ laps. For the first time, researchers can watch young brains in their initial encounters with language.

Using this technique, Petitto and her colleagues discovered a profound difference between babies brought up speaking one language and those who spoke two. According to popular theory, babies are born “citizens of the world,” capable of discriminating the sounds of any language. By the time they are a year old, however, they seemed to have lost this ability, homing in exclusively on the sounds of their mother tongue. That seemed to be the case with monolinguals. But Petitto’s study found that bilingual children showed increased neural activity in response to completely unfamiliar languages even at the end of their first year.

de Lange, Catherine. 2012. "Educators once opposed raising bilingual children. Experts now say it’s beneficial.". Washington Post. Posted: Available online:

Tuesday, June 26, 2012

Menstrual huts protect Dogon men from cuckoldry

ENSURING your partner doesn't cheat is a perennial problem. Perhaps one solution is religion.

Beverly Strassmann at the University of Michigan in Ann Arbor has spent years studying the Dogon people of Mali, west Africa. Women who practise the traditional Dogon religion, unlike those who are Muslim or Christian, spend five days a month around the time of menstruation in a highly visible "menstrual hut".

Strassmann tested paternity in 1700 Dogon father and son pairs and found that those who practised the traditional religion were four times less likely to be raising someone else's son than those who practised Christianity (Proceedings of the National Academy of Sciences, DOI: 10.073/pnas.1110442109).

The findings suggest that the huts make it easier for husbands to monitor wives close to fertile periods. No differences were observed between the Dogon and the Muslim group, perhaps because women are required to tell their husbands when they menstruate.

Strassmann suggests that these traditions may have developed as a way to boost reproductive success.

New Scientist. 2012. "Menstrual huts protect Dogon men from cuckoldry". New Scientist. Posted: June 10, 2012. Available online:

Monday, June 25, 2012

(Ab)use of World Heritage Site causes rifts in Bosnia and Herzegovina

What happens when a theatre of war is elevated to a World Heritage Site while the wounds are still raw? In Bosnia and Herzegovina, the World Heritage Sites have become podiums from which various groups proclaim wrongs done to them in the war. This is shown in a thesis by ethnologist Dragan Nikolić at Lund University, Sweden.

Dragan Nikolić has studied how sites that are included on UNESCO's list of World Heritage Sites – the old bridge in Mostar, the bridge over the Drina in Višegrad, and the nomination of the old town in Jajce – have gained a partly different meaning for the local people than that intended by national politicians and the international community.

World Heritage Sites have mainly been seen as a valuable asset for people's identity and a method to market locations. The thesis, Three Towns, Two Bridges and a Museum. Memory, Politics and World Heritage in Bosnia and Herzegovina, poses the question of what happens to World Heritage Sites where culturicide has been committed. Dragan Nikolić shows how the sites have been used strategically in political contexts and how they have been used and abused tactically in day-to-day life at transnational, national, local and individual level. The studies illustrate how the official memory of the World Heritage Sites often collides with the individual memories of members of the population.

"Instead of becoming symbols of reconciliation and pride, the bridges in Mostar and Višegrad, for example, became trouble spots. They were used to reinforce the memory of past injustices and to uphold a victims' perspective in the collective memory. They became a symbol for the role of victim. The people fight over who has suffered most", says Dragan Nikolić.

However, the thesis also gives examples of positive aspects of the involvement of civil society, such as in the case of the AVNOJ museum in Jajce, where many representatives and organisations came together to reinterpret the past.

The thesis follows both the intentions of the authorities and the frustration of the local population when symbolic actions have come before practical engagement, as well as how memorials have become weapons in a conflict that has been resolved only on the surface.

"My research shows that we cannot trivialise either cultural heritage monuments or people's memories; rather, we must strive to understand the interplay between them. Strategies and policies for World Heritage Sites must be changed and the authorities must follow up what happens after a place is designated a World Heritage Site, i.e. spend more time on the use and the practices that develop around this type of monument", says Dragan Nikolić.

Dragan Nikolić grew up in Bosnia Herzegovina and came to Sweden as a refugee in 1993 at the age of 17. This has given him a unique insider and outsider perspective in the work on his thesis. He defended his thesis in ethnology on 25 May at Lund University. The title of the thesis is Three Towns, Two Bridges and a Museum. Memory, Politics and World Heritage in Bosnia and Herzegovina.

EurekAlert. 2012. "(Ab)use of World Heritage Site causes rifts in Bosnia and Herzegovina". EurekAlert. Posted: June 7, 2012. Available online:

Sunday, June 24, 2012

Anthropologists Finds High Levels of Omega-3 Fatty Acids in Breast Milk of Amerindian Women

Working with researchers at the University of Pittsburgh and the Cincinnati Children's Hospital, anthropologists at UC Santa Barbara have found high levels of beneficial omega-3 fatty acids in the breast milk of economically impoverished Amerindian woman as compared to women in the United States.

Their research appears in the current issue of the journal Maternal and Child Nutrition.

The study compared breast milk fatty acid composition in U.S. and Tsimane women. The Tsimane live in Amazonian Bolivia, and eat a diet consisting primarily of locally grown staple crops, wild game, and freshwater fish. Samples of Tsimane mothers' milk contained significantly higher percentages of the omega-3 fatty acid docosahexaenoic acid (DHA), which is crucial for infant cognitive and visual development.

Additionally, the percentages of DHA in breast milk did not significantly decrease across the first two years postpartum, the period during which infant brains experience peak growth and maximal uptake of DHA. This was also true for the U.S. women, and the study suggests that extended breastfeeding by both U.S. and Tsimane mothers may provide infants with a constant source of DHA during the critical period of brain development.

"The fatty acid composition of breast milk varies with the fatty acid composition of a mother's diet and fat stores. Ancestral humans likely consumed omega-6 and omega-3 fatty acids in equal proportions," said Melanie Martin, a doctoral student in UCSB's Department of Anthropology, and the study's lead researcher. "Tsimane mothers' omega-6 to omega-3 ratios were four to one, much closer to the ancestral estimates than observed in U.S. women."

Unfortunately, the ratio of omega-6 to omega-3 in industrialized diets varies from 10 to 1 to as high as 20 to 1. This is most likely due to the absence of fresh fish, and regular consumption of processed foods and vegetable oils rich in linoleic acid (an omega-6), as well as trans fats. These high levels of omega-6 have been linked to increased risks of obesity, inflammation, and cardiovascular disease, and interfere with the synthesis of DHA and other omega-3 fatty acids.

"The Tsimane mothers' average milk DHA percentage was 400 percent higher than that of the Cincinnati mothers, while their average percentages of linoleic and trans fatty acids were 84 percent and 260 percent lower, respectively," said Martin. "Despite living in economically impoverished conditions, Tsimane mothers produce breast milk that has more balanced and potentially beneficial fatty acid composition as compared to milk from U.S. mothers."

The study comes in the wake of the May 21 issue of Time magazine, which reignited debate over the appropriate age at which a child should top nursing. "Buzz about the recent Time magazine cover missed the point," noted Steven Gaulin, professor of anthropology at UCSB, and one of the study's co-authors. "The American diet is eroding one of the most important benefits breast milk can provide -- fats that are critical to infant brain development. It's not surprising that, among developed nations, American children are last on international tests of math and science."

The study's findings highlight important questions about infant formula, the fatty acid content of which is based on the breast milk of U.S. mothers. "The study suggests that standards of fatty acid composition for infant formulas should be derived from populations such as the Tsimane," Martin explained. "And nutritional recommendations for infants should account for the prolonged requirements of fatty acids that breast milk naturally provides."

Also contributing to the study was Michael Gurven, professor of anthropology at UCSB.

ScienceDaily. 2012. "Anthropologists Finds High Levels of Omega-3 Fatty Acids in Breast Milk of Amerindian Women". ScienceDaily. Posted: June 9, 2012. Available online:

Saturday, June 23, 2012

Does Cooperation Require Both Reciprocity and Alike Neighbors?

Max Planck scientists have developed a new theoretical model on the evolution of cooperation.

Evolution by definition is cold and merciless: it selects for success and weeds out failure. It seems only natural to expect that such a process would simply favour genes that help themselves and not others. Yet cooperative behaviour can be observed in many areas, and humans helping each other are a common phenomenon. Thus, one of the major questions in science today is how cooperative behaviour could evolve. Scientists from the Max Planck Institute of Evolutionary Biology in Plön, Harvard University, and the University of Amsterdam have now developed a new model combining two possible explanations -- direct reciprocity and population structure -- and found that both repetition and structured population are essential for the evolution of cooperation. The researchers conclude that human societies can best achieve high levels of cooperative behaviour if their individuals interact repeatedly, and if populations exhibit at least a minor degree of structure.

The scientists addressed the question how cooperative behaviour could evolve using a game called the prisoner's dilemma, which considers two types of players: co-operators who pay a cost to help others; and defectors who avoid paying the cost, while reaping benefits from the co-operators they interact with. In general, everyone would be better off if they had engaged in cooperation, but from the point of view of the individual, defection is more beneficial. Selection will therefore always favour the defectors, and not cooperation. Researchers have used population structure and direct reciprocity to explain why cooperation has nevertheless evolved. In structured populations, co-operators are more likely to interact with other co-operators and defectors with defectors. Direct reciprocity involves the repetition of interaction and is therefore based on experiences gained from prior events involving cooperation. In the past, both approaches have been regarded separately.

Using computer simulations and mathematical models, a group of scientists around Julian Garcia from the Max-Planck Institute of Evolutionary Biology in Plön have developed a new model that is taking both concepts into account. They discovered that direct reciprocity alone is not enough, and that population structure is necessary in order to reach a high level of cooperation. When there is some reciprocity, the average level of cooperation increases because alike types are more likely to interact with each other. Additionally, the researchers observed that cooperation occurs if cooperative and defective individuals are highly clustered and repetition is rare. And surprisingly, too much repetition can even harm cooperation in cases when the population structure makes cooperation between individuals very likely. This is due to the fact that reciprocity can protect defectors from invasion by defectors in a similar manner that it prevents cooperation from being invaded by defectors.

"Without population structure, cooperation based on repetition is unstable," Garcia explains one of the main findings. This is especially true for humans, where repetition occurs regularly and who live in fluid, but not totally unstructured populations. A pinch of population structure helps a lot if repetition is present. "Therefore, the recipe for human cooperation might be: a bit of structure and a lot of repetition," says Julian Garcia. This phenomenon results in a high average level of cooperation.

ScienceDaily. 2012. "Does Cooperation Require Both Reciprocity and Alike Neighbors?". ScienceDaily. Posted: June 8, 2012. Available online: Max-Planck-Gesellschaft. "Does cooperation require both reciprocity and alike neighbors?." ScienceDaily, 8 Jun. 2012. Web. 17 Jun. 2012.

Friday, June 22, 2012

Scientists are accused of distorting theory of human evolution by misdating bones

Briton says Spanish researchers are out by 200,000 years and have even got the wrong species

It is the world's biggest haul of human fossils and the most important palaeontology site in Europe: a subterranean chamber at the bottom of a 50ft shaft in the deepest recesses of the Atapuerca cavern in northern Spain. Dozens of ancient skeletons have been unearthed.

La Sima de los Huesos – the Pit of Bones – has been designated a Unesco world heritage site because of its importance to understanding evolution, and millions of euros, donated by the EU, have been spent constructing a museum of human antiquity in nearby Burgos.

But Britain's leading expert on human evolution, Professor Chris Stringer, of the Natural History Museum, has warned in the journal Evolutionary Anthropology that the team in charge of La Sima has got the ages of its fossils wrong by 200,000 years and has incorrectly identified the species of ancient humans found there.

Far from being a 600,000-year-old lair of a species called Homo heidelbergensis, he believes the pit is filled with Neanderthal remains that are no more than 400,000 years old. The difference in interpretation has crucial implications for understanding human evolution.

"The Atapuerca finds are hugely important," said Stringer. "There is no other site like it in terms of numbers of bones and skulls of our ancient predecessors. It is the world's biggest collection of ancient human fossils and the team there has done a magnificent job in excavating the site. However, if we cannot correctly fix the age and identity of the remains then we are in trouble. Getting that wrong even affects how we construct our own evolution."

La Sima de los Huesos was discovered by potholers exploring Atapuerca's cavern system. One brought back a few fragments of human bone. Excavations led by Juan Luis Arsuaga, of Madrid university, began in 1990 and within two years had uncovered two complete human brain cases. Ribcages, leg bones and jawbones were also dug up. Arsuaga tentatively dated the finds as being 300,000 years old.

Since then, the remains of 28 bodies have been dug up, the world's greatest single haul of ancient human fossils. During this time, Arsuaga and his team pushed back the dates of their finds to 600,000 years ago and assigned them as belonging to Homo heidelbergensis.

This dating and identification has caused increasing upset among other palaeontologists. The scientists at La Sima believe H heidelbergensis is an ancestor of Neanderthals but not of Homo sapiens. However, others, including Stringer, believe it is indeed an ancestor of our species.

"The problem is that many of the skeletons unearthed at La Sima clearly have Neanderthal features," said Stringer. "In particular, their teeth and jaws are shaped very like those of Neanderthals. But all other evidence indicated Neanderthals did not appear on the scene for another 200,000 years. Dating these bones to such an early date completely distorts our picture of our evolution."

This criticism is supported by Phillip Endicott of the Musée de l'Homme, Paris. His studies of human and Neanderthal DNA have shown the latter did not appear as a separate species until 400,000 years ago. "Yet the bones in La Sima, which bear Neanderthal features, are supposed to be 600,000 years old," he said. "This cannot be true."

Another criticism is of the method used to date the Pit of Bones. A stalagmite found just above the remains has been dated as 600,000 years old, using natural uranium isotopes, and Sima scientists argue that the fossils must be older. They say the 28 bodies were thrown into the pit as an act of reverence for the dead and that the stalagmite grew over the sediment containing the bones.

However, this interpretation is controversial. No one has found any other evidence of ceremonial behaviour in humans of that antiquity. In addition, there is a deficit of small finger and toe bones. "If complete bodies were thrown in there, you would expect to see every piece of human anatomy down there," said Stringer. "But you don't. A lot of skeletal parts seem to be missing."

Yolanda Fernández-Jalvo and Peter Andrews, of, respectively, the Natural History Museums of Madrid and London, suggest the absence of small bones is best explained by assuming the bodies came from the cave system and were washed there by flood. Fingers and toes would have been lost as skeletons were swept into the pit where the stalagmite could already have formed.

However, Arsuaga has rejected this analysis. "You can call [the fossils] early Neanderthals or give them another name, it does not matter. I prefer to give a different name." But he admitted the 600,000-year age his team had put on the Sima fossils did look too early. "We are working on that," he said.

McKie, Robin. 2012. "Scientists are accused of distorting theory of human evolution by misdating bones". The Guardian. Posted: June 10, 2012. Available online:

Thursday, June 21, 2012

Homo heidelbergensis was only slightly taller than the Neanderthal

The reconstruction of 27 complete human limb bones found in Atapuerca (Burgos, Spain) has helped to determine the height of various species of the Pleistocene era. Homo heidelbergensis, like Neanderthals, were similar in height to the current population of the Mediterranean.

Along with its enormous quantity of fossils, one of the most important features of the Sima de los Huesos (SH) site in Atapuerca, Burgos, is the splendid state of the findings. They are so well conserved that the 27 complete bones from some 500,000 years ago have been reconstructed.

"The incredible collection allows us to estimate the height of species such as Homo heidelbergensis, who inhabited Europe during the Middle Pleistocene era and is the ancestor of the Neanderthal. Such estimations are based solely on analysis of the large complete bones, like those from the arm and the leg," as explained to SINC by José Miguel Carretero Díaz, researcher at the Laboratory of Human Evolution of the University of Burgos and lead author of the study that has been published in the 'Journal of Human Evolution' journal.

In addition, since bones were complete, the researchers were able to determine whether they belonged to a male or female and thus calculate the height of both men and women. "Estimations to date were based on incomplete bone samples, the length of which had to be estimated too. We also used to use formulas based on just one reference population and we were not even sure as to its appropriateness," outlines the researcher.

Since the most fitting race or ecology for these human beings was unknown, scientists used multiracial and multigender formulas to estimate the height for the entire population in order to reduce the error margin and get a closer insight on the reality. As Carretero Díaz points out, "we calculated an overall average for the sample and one for each of the sexes. The same was done with the Neanderthal and Cro-Magnon fossils."

The results suggest that both men and women in the Sima de los Huesos population were on average slightly higher than Neanderthal men and women. "Neither can be described as being short and both are placed in the medium and above-medium height categories. But, both species featured tall individuals," assured the experts.

The height of these two species is similar to that of modern day population of mid-latitudes, like in the case of Central Europe and the Mediterranean.

The humans who arrived in Europe during the Upper Palaeolithic era, Cro-Magnons or anatomically modern humans, replaced the Neanderthal populations. They were significantly taller than other human species and their average height for both sexes was higher, falling in the very tall individual category.

Height remained the same for some 2 million years

According to the researchers, putting aside the margin corresponding to small biotype species like Homo habilis (East Africa), Homo georgicus (Georgia) and Homo floresiensis (Flores in Indonesia), all documented humans during the Early and Middle Pleistocene Era that inhabited Africa (Homo ergaster, Homo rhodesiensis), Asia (Homo erectus) and Europe (Homo antecessor, Homo heidelbergensis and Homo neanderthalensis) seemed to have medium and above-medium heights for the most part of two millions years. However, the researchers state that "amongst every population we have found a tall or very tall individual."

In their opinion, this suggests that the height of the Homo genus remained more or less stable for 2 million years until the appearance of a "ground-breaking species in this sense" in Africa just 200,000 years ago. These were the Homo sapiens, who were initially significantly taller than any other species that existed at the time.

"The explanation is found in the overall morphological change in the body biotype that prevailed in our species compared to our ancestors. The Homo sapiens had a slimmer body, lighter bones, longer legs and were taller," adds the researcher.

A lighter body aided survival

Scientists have documented various advantages that made the sapiens biotype more adaptable. These include their thermoregulatory, obstetric and nutritional make-up but in the eyes of the experts, the greatest advantage of this new body type was increased endurance and energy.

Carretero Díaz indicates that "larger legs, narrower hips, being taller and having lighter bones not only meant a reduction in body weight (less muscular fat) but a bigger stride, greater speed and a lower energy cost when moving the body, walking or running."

This type of anatomy could have been highly advantageous in terms of survival in Eurasia during the Upper Pleistocene Era when two intelligent human species (the light-bodied Cro-Magnons and Neanderthals) had to face difficult climatic conditions, drastic changes in ecosystems and ecological competition.

EurekAlert. 2012. "Homo heidelbergensis was only slightly taller than the Neanderthal". EurekAlert. Posted: June 6, 2012. Available online:

Wednesday, June 20, 2012

'Vampire' Skeletons Found in Bulgaria

Two medieval "vampire" skeletons emerged near a monastery in the Bulgarian Black Sea town of Sozopol, local archaeologists announced.

Dating back 800 years to the Middle Ages, the skeletons were unearthed with iron rods pierced through their chests -- evidence of an exorcism against a vampire. The ritual was aimed at preventing potentially dangerous people, such as enemies, murderers or individuals who died suddenly from a strange illness, from turning into vampires after death.

"The practice was common in some Bulgarian villages up until the first decade of the 20th century," Bozhidar Dimitrov, chief of the National History Museum in Sofia, told reporters.

The newly discovered skeletons are the latest in a series of finds across Europe. According to Dimitrov, over 100 skeletons, buried in the same manner, had been unearthed in Bulgaria only.

Vampires of the time were quite different from the aristocratic blood-sucking character depicted in Bram Stoker's 1897 Gothic horror novel "Dracula" and in innumerable Hollywood movies.

Indeed, the vampire legend originated from the disturbing appearance of decomposing bodies that had succumbed to the plagues that ravaged Europe between 1300 and 1700.

During those epidemics, mass graves were often reopened to bury fresh corpses and gravediggers would stumble into bodies that were bloated by gas.

Featuring a hole in the shroud used to cover their faces, these bodies showed individuals with their hair still growing, their teeth appearing through the shroud, and blood seeping out of their mouths.

In a time before germ theory, when the decomposition of corpses was not well understood, these individuals appeared like they were still alive, drinking blood and eating their shrouds.

Modern forensic science would explain that the shrouds were consumed by bacteria found in the mouth area, but at that time it was believed that these "shroud-eaters" were vampires who spread pestilence.

A stake in the heart and a stone wedged into the mouth would kill the undead creatures, while iron rods pierced through their chest would pin them into their burials to prevent them from rising from the graves and terrorizing the living.

According to archaeologist Petar Balabanov, who in 2004 discovered six nailed-down skeletons at a site near the Bulgarian town of Debelt, the vampire-slaying ritual had also been practiced in neighboring Serbia and across the Balkans.

Lorenzi, Rossella. 2012. "'Vampire' Skeletons Found in Bulgaria". Discovery News. Posted: June 6, 2012. Available online:

Tuesday, June 19, 2012

The extraordinary 2,000-year-old computer that you've never heard of

The Antikythera mechanism was designed to predict movements of the sun, moon and planets. Why isn't it better known?

Right, that's enough of the Queen for now. Have you ever heard of the Antikythera mechanism? You have? Well done. If not, I suspect you're in good company and the fact that I learned about it from a fascinating BBC4 programme – the high point of my jubilee weekend – on Sunday night is unlikely to broaden public knowledge as much as we might hope.

What was explained in The Two-Thousand-Year-Old Computer – you'll still catch it here on iPlayer – strikes me as staggering for two quite different reasons which I'll explain. But first, what is the Antikythera mechanism?

Put simply by an ignorant layman – here's Wiki's basic summary and here's a more ambitious and technical note – it is the accidental 1900-01 discovery in a shipwreck off an island (hence the name) between Greece and Crete of a complex and intriguing fragment, its origin later dated to about 100BC. It has taken a lot of clever people and equipment most of the 20th century to reveal its astonishing secrets.

What was initially dismissed as an anomaly – a rock with a cogwheel embedded in it must be so for other reasons, including much later shipwrecks – was a device with at least 30 (some say 70) gears, all precision engineered (the teeth were hand-cut equilateral triangles) and designed to predict the movements of the sun and moon, plus six of our closer planetary neighbours. The calendar dial can be moved to adjust for that inconvenient extra quarter day in the solar year.

Would it have calculated this morning's transit of Venus? You tell me. Its sophistication is far beyond my comprehension, a machine in the modern sense of the word but 2,100 years old. Perhaps you knew all this. The internet is full of good stuff once you know what you're looking for. My brother, who is an engineer, had never heard of it, yet it seems to have been dubbed the world's first computer for some time without either of us being informed. Nature magazine published long, learned pieces as long ago as 2006.

I won't spoil the detective story about how exactly its mysteries were – more or less – resolved, except to say that it shows current collaborative science in a very attractive light, with several countries and disciplines involved and a 12-tonne British imaging machine flown to Athens because the Antikythera mechanism is too fragile to move. It's all there in the programme on BBC4, the station that doesn't treat us like idiots.

Point No 1: how extraordinary was the ancient world, which we know both discovered and set down fabulous amounts of knowledge and wisdom – from philosophy and politics to a range of natural sciences, including astronomy and medicine – much of it lost to the dark ages that engulfed our own corner of Europe after the fall of Rome in AD476, only to creep back via Islam in the succeeding 1,000 years.

But this is surely something of a different magnitude, not simply an idea or an analysis – brilliant, but not always right – but a complex bit of manufacturing, a calculating machine deployed (they think) using a long-lost crank. Wow! What ancient Leonardo or Isaac Newton (two oft-cited men of rare and solitary genius) could have done this?

The BBC4 programme-makers endorse the view that clues on the mechanism point to its origin in Corinth and that it can therefore be plausibly attributed to the great Archimedes (c287 BC – c212 BC), mathematician and physicist extraordinary.

It was his skill in inventing weapons of war that allowed the Greek colony at Syracuse at the eastern tip of Sicily to resist the siege imposed by a Roman army for two years. As every schoolboy might still know General Marcus Marcellus gave express orders that Archimedes should be captured, not killed (no drone attack for him, Mr Obama!) when treachery ended the siege in 212 in the second Punic war.

But Plutarch says he was too busy solving an equation when summoned to the general's presence and an irate soldier ran him through. Before we tut-tut too much I should add that this sort of accident does happen from time to time. The French Revolution executed Antoine Lavoisier, the father of modern chemistry, for tax fraud in 1794 (his day-job as a tax collector was an unpopular one). "The republic needs neither scientists nor chemists," said the dolt of a judge. The loss was immeasurable.

But let's not get too smug. In our own time the British authorities hounded Alan Turing over his sexuality, probably causing his death by suspected suicide. As a pioneer of computer science Turing was up there with the biggest names, including Charles Babbage – the Archimedes of Victorian England whose calculating machine would have worked if the manufacture tolerances of the time had been good enough.

Did Archimedes's version deliver the ancient bacon? It would seem so. Whatever the Antikythera mechanism was doing in the heavily laden Roman boat that sank off Antikythera, we know that Marcellus, evidently a clever man, took a couple of Archimedes machines home with him. Cicero, quite an authoritative source, makes reference to them.

Yet this takes me to Point No 2. Why didn't we all learn about this in school, if not in my school days when the late Derek de Solla Price, one of this saga's heroes, was spending years trying to rebuild the mechanism, then later? Why didn't my kids or yours get this staggering intellectual achievement of the ancient world thrust down their complacent throats?

Part of the answer must surely be the inherent arrogance of mankind at any one time. The Americans have always thought they are pretty hot. So did we for 300 years (less so now, even before the Euro 2012 football gets under way in Poland and Ukraine), the Chinese always have, despite the occasional 500-year relegation. The ancient Greeks dismissed non-Greeks as barbarians.

So it's always awkward to admit how much we owe to others, especially blokes with sweaty armpits and open-toed sandals, who didn't know an iPad from DNA. The idea that a vast body of knowledge can be lost or buried – which is pretty much what happened – is always disturbing because it opens up the possibility that it might happen again.

Newton got it right when he said: "If I have seen further than other men it is because I have stood on the shoulders of giants." Lesser people, most of us, find that hard to admit. The former US defence secretary Donald Rumsfeld, whose arrogance made him as much responsible as anyone for the debacle of the US-UK occupation of Iraq, ignored centuries of past wisdom in planning his war.

Yet he also famously said a wise thing. "There are known knowns; there are things we know that we know. There are known unknowns; that is to say there are things that we now know we don't know. But there are also unknown unknowns – there are things we do not know we don't know."

Naturally, a lot of people laughed at him. But it's always worth bearing in mind that we're not as smart as we're tempted to think we are. To become aware of the Antikythera mechanism is humbling – as Queen Elizabeth said in a more transient context only last night.

2012. "The extraordinary 2,000-year-old computer that you've never heard of". The Guardian. Posted: June 6, 2012. Available online:

Monday, June 18, 2012

Ancient Statue Reveals Prince Who Would Become Buddha

In the ruins of a Buddhist monastery in Afghanistan, archaeologists have uncovered a stone statue that seems to depict the prince Siddhartha before he founded Buddhism.

The stone statue, or stele, was discovered at the Mes Aynak site in a ruined monastery in 2010, but it wasn't until now that it was analyzed and described. Gérard Fussman, a professor at the Collège de France in Paris, details his study in "The Early Iconography of Avalokitesvara" (Collège de France, 2012).

Standing 11 inches (28 centimeters) high and carved from schist — a stone not found in the area — the stele depicts a prince alongside a monk. Based on a bronze coin found nearby, Fussman estimates the statue dates back at least 1,600 years. Siddhartha lived 25 centuries ago.

The prince is shown sitting on a round wicker stool, his eyes looking down and with his right foot against his left knee. He is "clad in a dhoti (a garment), with a turban, wearing necklaces, earrings and bracelets, sitting under a pipal tree foliage. On the back of the turban, two large rubans [are] flowing from the head to the shoulders," writes Fussman in his new book. "The turban is decorated by a rich front-ornament, without any human figure in it."

The monk stands at the prince's right side, his right forearm shown upright. In his right hand the monk holds a lotus flower or palm (now broken), and in his left is a round object of some kind.

Based on the iconography of the stele, particularly the pipal leaves, Fussman believes the prince is Gautama Siddhartha Sakyamuni, who is said to have achieved enlightenment, become a Buddha — someone of divine wisdom and virtue — and founded the religion of Buddhism. This stele shows him at an early moment in his life, when he has yet to start his fateful journey of enlightenment.

Siddhartha's story

According to the story, Siddhartha's father wanted him to follow a worldly path and tried to keep his son cloistered in a palace.

"Lotus pools were made for me at my father's house solely for my use; in one, blue lotuses flowered, in another white, and in another red," says Siddharthain ancient writings attributed to him. "A white sunshade was held over me day and night so that I would not be troubled by cold or heat, dust or grit or dew." (This translation is from Rupert Gethin's "The Foundations of Buddhism," Oxford University Press, 1998.)

The prince's life would change when he ventured outside the palace and saw the real world. "As soon as he left the palace he became pessimistic," Fussman told LiveScience, "because by meeting these people, he knew that everybody is to work, everybody may become ill, everybody is to die."

He grew disenchanted with palace life and left, becoming a poor ascetic.

Tibetan clues

Fussman said that this stele supports the idea that there was a monastic cult, in antiquity, dedicated to Siddhartha's pre-enlightenment life. This idea was first proposed in a 2005 article inthe journalEast and West by UCLA professor Gregory Schopen. Schopen found evidence for the cult when studying the Tibetan version of the monastic code, Mulasarvastivada vinaya. [Religious Worship: Top 10 Cults]

It's a "cult focused on his image that involved taking it in procession through the region and into town," Schopen wrote. "A cult tied to a cycle of festivals celebrating four moments, not in the biography of the Buddha but in the pre-enlightenment period of the life of Siddhartha."

One section of the code authorizes carrying the image of Siddhartha (referred to as a Bodhisattva) on a wagon.

Whether or not the newly discovered stele went on a wagon ride, Fussman said the depiction of Gautama Siddhartha Sakyamuni before he became a Buddha provides further evidence of the existence of this cult. "Here also you have an instance of it," he said in the interview, "the Buddha before he became a Buddha."

Excavations continue at the Mes Aynak site as scientists explore the complex in an effort to save the artifacts before the area is disturbed by copper mining.

Jarus, Owen. 2012. "Ancient Statue Reveals Prince Who Would Become Buddha". Live Science. Posted: June 6, 2012. Available online:

Sunday, June 17, 2012

Great Wall of China Twice As Long As Thought

The Great Wall of China is more than twice as long as originally believed, according to the first definitive archaeological survey of the iconic ancient defensive structure.

Released by the State Administration of Cultural Heritage (SACH), the survey began in 2007, mapping every trace of the wall across 15 Chinese provinces.

It emerged that the wall is much longer than previously thought. Indeed, it measures 13,170.6956 miles, or 21,196.18 km. A preliminary study released in 2009 estimated the wall to snake 5,500 miles, or 8,850 km across the country.

A total of 43,721 heritage sites were identified during the survey, "including stretches of the wall, defense works and passes, as well as other related Great Wall facilities and ruins," Tongo Mingkang, SACH deputy chief, said.

Known to the Chinese as the "Long Wall of 10,000 Li", the Great Wall is the world's largest human-made structure -- a series often overlapping fortifications made of stone, bricks and earthen works whose construction begun as early as the 7th century BC.

The defensive structure was first linked up under Emperor Qin Shi Huang in about 220BC. to protect the ancient Chinese empire from marauding tribes from the north.

Since then, many dynasties have maintained and renovated the wall. The majority of the existing structure was reconstructed during the Ming Dynasty (1368-1644).

Today, only 8.2 percent of the wall built during the Ming Dynasty is intact, with the rest in poor condition, said the report.

Listed as a Unesco world heritage site in 1987, the wall has been heavily damaged from human activities, infrastructure development and tourism.

A large amount of the wall has collapsed and in some sections, only its foundation remains, the five-year survey concluded.

"The saving and preserving of the Great Wall's relics should not be delayed," the report stressed.

By 2015, the SACH will establish general guideline for protection of the Great Wall and set up a monitoring system to ensure an effective preservation, the state-run Xinhua news agency reported.

Lorenzi, Rosella. 2012."Great Wall of China Twice As Long As Thought". Discovery News. Posted: June 7, 2012. Available online:

Saturday, June 16, 2012

UH research team uses airborne LiDAR to unveil Honduran archaeological ruins

Research team's results mark the successful completion of the first light detection and ranging survey of Honduras' Mosquitia region, one of the world's least-explored virgin rainforests

A field team from the University of Houston and the National Science Foundation (NSF) National Center for Airborne Laser Mapping (NCALM) has mapped a remote region of Honduras that may contain the legendary lost city of Ciudad Blanca.

The results, recently announced by Honduras President Porfirio Lobo, mark the successful completion of the first light detection and ranging (LiDAR) survey of Honduras' Mosquitia region, one of the world's least-explored virgin rainforests.

An initial analysis of the LiDAR survey has identified ruins that could be those of pre-Columbian Ciudad Blanca or other long-hidden sites. The information provides achaeologists with the precise locations of features within fractions of meters for further study.

UH serves as the operational center for NCALM, a collaborative program between UH and the University of California at Berkeley. NCALM focuses on the collection of research quality, airborne LiDAR data for NSF principal investigators, the advancement of airborne LiDAR technology and applications and the education of students to fill positions in academic, government and commercial organizations requiring knowledge of airborne LiDAR.

The NCALM Operational Center's experience in completing more than 150 projects across the nation was critical to the successful completion of the Honduras mapping project, which was initiated by UTL Scientific LLC., a group formed by principals of the Honduran LiDAR survey project.

UTL project leader Steve Elkins has been fascinated with the Mosquitia rainforest since his first visit there nearly 20 years ago, but he has been frustrated by the inability of satellite imagery to see under the extremely thick canopy. He contacted researchers at UH, NCALM and Geosensing Systems Engineering (GSE) Graduate Research Program to overcome this obstacle.

UH professors Ramesh L. Shrestha and William E. Carter have been working with refining and applying airborne LiDAR to unveil the surface of the earth, primarily for earth scientists researching surface processes, for more than a decade.

In 2009, the UH researchers and a field team composed of Michael Sartori, Juan Fernandez-Diaz and Abhinav Singhania successfully mapped the Caracol archaeological site in Belize using airborne LiDAR. Even though the site was covered with dense rainforest, the LiDAR data captured building ruins and agricultural terraces not discovered by archaeologists working on the ground for more than 25 years.

In the Honduras project, the UH team blanketed the area with as many 25 to 50 laser pulses per square meter – a total of more than four billion laser shots. A number of areas were mapped and the images collected were reduced and filtered to remove the vegetation and provide "bare earth" digital elevation models in near real-time in the field.

The digital elevation models were then used to produce geodetic images of the terrain's surface below the rainforest, and those images were searched by eye to study geomorphological features as well as potential archaeological ruins.

The project has demonstrated the power of airborne laser mapping to locate archaeological ruins in regions covered with thick forest, and it appears that the method will be used widely in the years ahead.

EurekAlert. 2012. "UH research team uses airborne LiDAR to unveil Honduran archaeological ruins". EurekAlert. Posted: June 5, 2012. Available online:

Friday, June 15, 2012

Childbirth and death in Bioarchaeology

From the moment we began to walk upright, childbirth has been a difficult time for women as evolution selected larger and larger brains in our hominin ancestors so that today our newborns have heads roughly 102% the size of the mother’s pelvic inlet width (Rosenberg 1992).

Two recent articles in the International Journal of Osteoarchaeology both start by explaining that “despite this general acceptance of the vulnerability of young females in the past, there are very few cases of pregnant woman (sic) reported from archaeological contexts” (Willis & Oxenham, In Press) and “archaeological evidence for such causes of death is scarce and therefore unlikely to reflect the high incidence of mortality during and after labour”(Cruz & Codinha 2010:491).

The examples of burials of pregnant women that tend to get cited include two from Britain (both published in the 1970s), four from Scandinavia (published in the 1970s and 1980s), three from North America (published in the 1980s), one from Australia (1980s), one from Israel (1990s), six from Spain (1990s and 2000s), one from Portugal (2010), and one from Vietnam (2011) (most of these are cited in Willis & Oxenham). Additionally, there were unpublished reports: including a skeleton from Egypt, a bog body from England, and a skeleton from England.

Where are all the mother-foetus burials?

As with any bioarchaeological question, there are a number of reasons that we may or may not find evidence of practices we know to have existed in the past. Some key issues at play in recovering evidence of death in childbirth include:

  • Archaeological Theory and Methodology – From the dates of discovery of maternal-foetal death cited above, it’s obvious that these examples weren’t discovered until the 1970s.

  • Death at Different Times – Although some women surely perished in the middle of childbirth, along with a foetus that was obstructed, in many cases delivery likely occurred, after which the mother, foetus, or both died. With a difference between the time of death of the mother and child, a bioarchaeologist can’t say for sure that these deaths were related to childbirth. Even finding a female skeleton with a fetal skeleton inside it is not always a clear example, as there are forensic cases of coffin birth or postmortem fetal extrusion, when the non-viable fetus is spontaneously delivered after the death of the mother.

  • Cultural Practices – Another condition of being human is the ability to modify and mediate our biology through culture. This can be carried out through caesarean section, a surgical procedure that dates back at least to the origins of ancient Rome.

    Cultural interventions in childbirth

    It’s often assumed that the term caesarean section comes from the manner of birth of Julius Caesar, but it seems that the Roman author Pliny may have just made this up. The written record of the surgical practice originated as the Lex Regia (royal law) with the second king of Rome, Numa Pompilius (c. 700 BC), and was renamed the Lex Caesarea (imperial law) during the Empire. The law is passed down through Justinian’s Digest (11.8.2) and reads:

    “Negat lex regia mulierem, quae praegnas mortua sit, humari, antequam partus ei excidatur: qui contra fecerit, spem animantis cum gravida peremisse videtur.” The royal law forbids burying a woman who died pregnant until her offspring has been excised from her; anyone who does otherwise is seen to have killed the hope of the offspring with the pregnant woman. [Translation by K Killgrove]

    Caesarean sections and Roman burials

    In spite of the Romans’ passion for record keeping, there’s very little evidence of Caesarean-sections. It’s unclear how religiously the Lex Regia/Caesarea was followed in Roman times, which means it’s unclear how often the practice of C-section occurred. Would all women have been subject to these laws? Just the elite or just citizens? How often did the section result in a viable newborn? Who performed the surgery? It probably wasn’t a physician (since men didn’t generally attend births), but a midwife wouldn’t have been trained to do it either (Turfa 1994).

    Only two Roman-era examples involving young women are known, and it is quite interesting that they were already fertile. Age at menarche in the Roman world depended on health, which in turn depended on status, but it’s generally accepted that menarche happened around 14-15 years old and that fertility lagged behind until 16-17, meaning for the majority of the Roman female population, first birth would not occur until at least 17-19 years of age (Hopkins 1965, Amundsen & Diers 1969). These numbers have led demographers like Tim Parkin (1992:104-5) to note that pregnancy was likely not a major contributor to premature death among Roman women. But the female pelvis doesn’t reach skeletal maturity until the late teens or early 20s, so complications from the incompatibility in pelvis size versus foetal head size are not uncommon in teen pregnancies, even today (Gilbert et al. 2004).

    More interesting than the young age at parturition is the fact that both of these young women were likely buried with their foetuses still inside them, in direct violation of the Lex Caesarea.

    You can read the whole article here.

    Killgrove, Kristina. 2012. "Childbirth and death in Bioarchaeology". Past Horizons. Posted: Available online:

  • Thursday, June 14, 2012

    An Asian Origin for Human Ancestors?

    Researchers agree that our immediate ancestors, the upright walking apes, arose in Africa. But the discovery of a new primate that lived about 37 million years ago in the ancient swamplands of Myanmar bolsters the idea that the deep primate family tree that gave rise to humans is rooted in Asia. If true, the discovery suggests that the ancestors of all monkeys, apes, and humans—known as the anthropoids—arose in Asia and made the arduous journey to the island continent of Africa almost 40 million years ago.

    Until 18 years ago, fossils of every suspected early anthropoid were found in Egypt and dated to about 30 million years ago. Then, starting in the 1990s, researchers began discovering the remains of petite primates that lived 37 million to 45 million years ago in China, Myanmar, and other Asian nations. This suggested that anthropoids may have actually arisen in Asia and then migrated to Africa a few million years later. But paleontologists have lacked the fossils to show when and how these anthropoids trekked from Asia to Africa, says paleontologist K. Christopher Beard of the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania.

    In 2005, Beard and an international team of researchers sifting fossils of early fish, turtle, and ancestral hippo teeth from fossil beds near the village of Nyaungpinle in Myanmar found a molar the size of a kernel of popcorn. The tooth, dated to about 38 million years ago, belonged to a new species of ancient primate, which would have been the size of a small chipmunk. After several more years of arduous fieldwork, the team has collected just four molars of this primitive anthropoid, which they named Afrasia djijidae. "It's a difficult place to work; it took us 6 years to find four teeth," says Beard.

    The four molars were enough to show Beard and team leader Jean-Jacques Jaeger of the University of Poitiers in France that Afrasia was closely related to another primitive anthropoid that lived at about the same time, but in Africa—Afrotarsius libycus from Libya. When the researchers examined the teeth from the two primates under a microscope, they were so similar in size, shape, and age that they could have belonged to the same species of primate, says Beard. Such close resemblance between an Asian and African fossil anthropoid has "never been demonstrated previously," the authors write online today in the Proceedings of the National Academy of Sciences.

    On closer examination, however, the team noticed that the new molars from the Asian Afrasia were more primitive than those of Afrotarsius from Libya, particularly in the larger size of a tiny bulge at the back of its last lower molar. These primitive traits, as well as the greater diversity and age of early, or "stem," anthropoids in Asia rather than Africa suggest that this group arose in Asia and migrated to Africa 37 million to 39 million years ago. "Anthropoids didn't arrive in Africa until right before we find their fossils in Libya," says Jaeger.

    The Out-of-Asia scenario may have been complex. The team proposes that more than one species of anthropoid migrated from Asia to Africa at about this time, because there are at least two other types of early anthropoids alive at about the same time as Afrotarsius in Libya, yet they are not closely related to Afrotarsius or Afrasia. This may be because once they got to Africa, they found ideal lush conditions with few carnivores and underwent a "starburst of evolution," says Beard, rapidly giving rise to a number of new species.

    Others agree that if both the new species of primates from Myanmar and Libya are indeed early anthropoids, they would greatly strengthen the case for the Asian origins of anthropoids. "If proven, the biogeographical significance of these results is profound," says paleontologist Richard Kay of Duke University in Durham, North Carolina. It would show that there was a major migration of primates and probably other mammals between the two continents at a time when it was not easy to get across the ancient Tethys Sea that divided Africa from Asia. And for humans, it would suggest that our deepest primate roots were in Asia, not Africa.

    Still, the similarity between the species rests on just four molars of Afrasia, Kay notes, although teeth are the most reliable way to measure relatedness. And some researchers have yet to be convinced that Afrotarsius in Libya is a stem anthropoid rather than an ancestor of tarsiers, primates that are not anthropoids and, thus, are more distant relatives. Kay, however, says the scales are tipping toward an Asian origin. "We've all heard about Out-of-Africa for human origins," adds Beard. "Now we think there was an Out-of-Asia migration into Africa first."

    Gibbons, Ann. 2012. "An Asian Origin for Human Ancestors?" Science. Posted: June 4, 2012. Available online:

    Wednesday, June 13, 2012

    How Infectious Disease May Have Shaped Human Origins

    Roughly 100,000 years ago, human evolution reached a mysterious bottleneck: Our ancestors had been reduced to perhaps five to ten thousand individuals living in Africa. In time, "behaviorally modern" humans would emerge from this population, expanding dramatically in both number and range, and replacing all other co-existing evolutionary cousins, such as the Neanderthals.

    The cause of the bottleneck remains unsolved, with proposed answers ranging from gene mutations to cultural developments like language to climate-altering events, among them a massive volcanic eruption.

    Add another possible factor: infectious disease.

    In a paper published in the June 4, 2012 online Early Edition of The Proceedings of the National Academy of Sciences, an international team of researchers, led by scientists at the University of California, San Diego School of Medicine, suggest that inactivation of two specific genes related to the immune system may have conferred selected ancestors of modern humans with improved protection from some pathogenic bacterial strains, such as Escherichia coli K1 and Group B Streptococci, the leading causes of sepsis and meningitis in human fetuses, newborns and infants.

    "In a small, restricted population, a single mutation can have a big effect, a rare allele can get to high frequency," said senior author Ajit Varki, MD, professor of medicine and cellular and molecular medicine and co-director of the Center for Academic Research and Training in Anthropogeny at UC San Diego. "We've found two genes that are non-functional in humans, but not in related primates, which could have been targets for bacterial pathogens particularly lethal to newborns and infants. Killing the very young can have a major impact upon reproductive fitness. Species survival can then depend upon either resisting the pathogen or on eliminating the target proteins it uses to gain the upper hand."

    In this case, Varki, who is also director of the UC San Diego Glycobiology Research and Training Center, and colleagues in the United States, Japan and Italy, propose that the latter occurred. Specifically, they point to inactivation of two sialic acid-recognized signaling receptors (siglecs) that modulate immune responses and are part of a larger family of genes believed to have been very active in human evolution.

    Working with Victor Nizet, MD, professor of pediatrics and pharmacy, Varki's group had previously shown that some pathogens can exploit siglecs to alter the host immune responses in favor of the microbe. In the latest study, the scientists found that the gene for Siglec-13 was no longer part of the modern human genome, though it remains intact and functional in chimpanzees, our closest evolutionary cousins. The other siglec gene -- for Siglec-17 -- was still expressed in humans, but it had been slightly tweaked to make a short, inactive protein of no use to invasive pathogens.

    "Genome sequencing can provide powerful insights into how organisms evolve, including humans," said co-author Eric D. Green, MD, PhD, director of the National Human Genome Research Institute at the National Institutes of Health.

    In a novel experiment, the scientists "resurrected" these "molecular fossils" and found that the proteins were recognized by current pathogenic strains of E. coli and Group B Streptococci. "The modern bugs can still bind and could potentially have altered immune reactions," Varki said.

    Though it is impossible to discern exactly what happened during evolution, the investigators studied molecular signatures surrounding these genes to hypothesize that predecessors of modern humans grappled with a massive pathogenic menace between 100,000 and 200,000 years ago. This presumed "selective sweep" would have devastated their numbers. Only individuals with certain gene mutations survived -- the tiny, emergent population of anatomically modern humans that would result in everyone alive today possessing a non-functional Siglec-17 gene and a missing Siglec-13 gene.

    Varki said it's probable that humanity's evolutionary bottleneck was the complex result of multiple, interacting factors. "Speciation (the process of evolving new species from existing ones) is driven by many things," he said. "We think infectious agents are one of them."

    Science Daily. 2012. "How Infectious Disease May Have Shaped Human Origins". Science Daily. Posted: June 4, 2012. Available online:

    Tuesday, June 12, 2012

    How religion promotes confidence about paternity

    Religious practices that strongly control female sexuality are more successful at promoting certainty about paternity, according to a study published in the current issue of the Proceedings of the National Academy of Sciences.

    The study analyzed genetic data on 1,706 father-son pairs in a traditional African population—the Dogon people of Mali, West Africa—in which Islam, two types of Christianity, and an indigenous, monotheistic religion are practiced in the same families and villages.

    "We found that the indigenous religion allows males to achieve a significantly lower probability of cuckoldry—1.3 percent versus 2.9 percent," said Beverly Strassmann, lead author of the article and a biological anthropologist at the University of Michigan.

    In the traditional religion, menstrual taboos are strictly enforced, with women exiled for five nights to uncomfortable menstrual huts. According to Strassmann, the religion uses the ideology of pollution to ensure that women honestly signal their fertility status to men in their husband's family.

    "When a woman resumes going to the menstrual hut following her last birth, the husband's patrilineage is informed of the imminency of conception and cuckoldry risk," Strassmann said. "Precautions include postmenstrual copulation initiated by the husband and enhanced vigilance by his family."

    Across all four of the religions practiced by the Dogon people, Strassmann and colleagues detected father-son Y DNA mismatches in only 1.8 percent of father-son pairs, a finding that contradicts the prevailing view that traditional populations have high rates of cuckoldry. A similar rate of cuckoldry has been found in several modern populations, but a key difference is that the Dogon do not use contraception.

    The study, which was supported by funding from the National Science Foundation, is part of Strassmann's ongoing, 26-year study of the Dogon people.

    "The major world religions sprang from patriarchal societies in which the resources critical to reproduction, whether in the form of land or livestock, were inherited from father to son down the male line," Strassmann and colleagues write. "Consistent with patrilineal inheritance, the sacred texts set forth harsh penalties for adultery and other behaviors that lower the husband's probability of paternity. The scriptures also place greater emphasis on female than on male chastity, including the requirement of modest attire for women and the idealization of virginity for unmarried females."

    While previous studies have examined the evolutionary biology of patriarchy through primate antecedents or cultural factors, the current study is the first to investigate whether religions that more strongly regulate female sexuality are more successful at limiting the incidence of cuckoldry. "Although world religions do not have menstrual huts, they do share many tenets that may foster cuckoldry avoidance," the authors write. "For example, in Judaism, menstrual purity laws increase coital frequency around the time of ovulation. In Islam, paternity confusion is prevented by the Qur'an's rule that, after divorce, a woman must wait for three menstrual periods before remarrying. The Hindu text, 'The Laws of Manu,' admonishes against cuckoldry or 'sowing in another man's field.'

    "Strong statements against adultery and extramarital children are found in the Bible and, in Buddhism, adultery is a form of sexual misconduct. In preventing cuckoldry, religions use the dual strategy of social control in the public sphere (attendance at a place of worship or at a menstrual hut) and the fear of divine or supernatural punishment. In the United States, frequent church attendance and belief that the Bible is the word of God were the two most robust predictors of lower rates of self-reported extra-partner copulations."

    In short, Strassmann and colleagues maintain that the ideological and tactical similarities between these world religions and the Dogon religion have arisen in response to the same biological pressures. Religious patriarchy is directly analogous to the mate-guarding tactics used by animals to ensure paternity.

    EurekAlert. 2012. "How religion promotes confidence about paternity". EurekAlert. Posted: June 4, 2012. Available online:

    Monday, June 11, 2012

    Your Facebook Photo Is Shaped by National Culture

    Poke around Facebook and you’ll see your friends in all sorts of places: at the beach, at a party, at the ballpark, at home.

    Our profile pictures can be very different, but two social scientists noticed some patterns. Compared with people in, say, Taiwan, we Americans show ourselves looming larger in the frame, and smiling more broadly.

    This matters, say Chih-Mao Huang of the University of Illinois and Denise Park of the University of Texas at Dallas. They’ve now published a paper in the International Journal of Psychology, documenting how cultural differences show up online.

    “These are not conscious choices,” Dr. Park wrote in an email to ABC News. “This represents the lens through which the two cultures view the world. This relates, we believe, to a cultural bias to be more individualistic in the U.S. and more communal in Asia. We believe these values fundamentally sculpt one’s thought and choices, including design of a Facebook portrait.”

    Huang and Park say they did two studies of Facebook profile pictures, measuring how people in the U.S. and Taiwan chose to show themselves. They looked at more than 500 pictures in all.

    For the most part, they concluded, we all do the same thing: try to put the best foot (or face) forward. But here’s what’s different: While 12 percent of Americans posted pictures in which only their heads showed, just one Taiwanese subject (0.9 percent of the sample group) used such a close-up. The East Asian users tended to prefer wider shots; the backgrounds mattered to them as much as that they were in them.

    Similarly, Americans turn up the voltage for their shots. Fifteen percent more Americans were categorized in the paper as smiling broadly enough that their teeth showed.

    What does all this mean? Huang and Park write of the U.S. as an “individualistic and independent” culture, while people in Taiwan “deemphasize the face and to engage more contextual field information.” Social media — Facebook, in this case — make a giant lab for showing the differences.

    Co-author Huang, perhaps knowing people would check, had some fun on his own Facebook page. His profile photo shows him — from the back, looking up at the psychology building at the university.

    Potter, Ned. 2012."Your Facebook Photo Is Shaped by National Culture". ABC News Blogs - Technology. Posted: May 31, 2012. Available online:

    Sunday, June 10, 2012

    Ancient Egyptian Calendar Reveals Earliest Record of 'Demon Star'

    Ancient Egyptians may have chronicled the flickering of a star known as "the Demon," perhaps the earliest known record of a variable star, astronomers suggest.

    The ancient Egyptians wrote calendars that marked lucky and unlucky days. These predictions were based on astronomical and mythological events thought of as influential for everyday life. The best preserved of these calendars is the Cairo Calendar, a papyrus document dating between 1163 and 1271 B.C. The entry for each day is prefaced by three hieroglyphics that indicate either good or bad luck, with the characters often derived from events of mythology.

    Astronomers at the University of Helsinki in Finland had previously discovered that some of the fortunate days recurred in a pattern, every 29.6 days. This almost exactly matches the length of the lunar cycle — the time between two full moons. New moons may have been associated with bad luck.

    Dimming demon star

    The scientists also detected another pattern in the calendar, one that occurred every 2.85 days. Now the researchers suggest this approximately matches regular dimming of Algol, "the Demon Star," which lies approximately 93 light-years away in the constellation Perseus as one of the eyes of Medusa's head. Its name comes from the Arabic phrase, ra's al-ghul, which means "the demon's head."

    Algol is the brightest known example of an eclipsing binary system — the large bright member of the system, Beta Persei A, regularly gets eclipsed by the dimmer Beta Persei B. From our point of view, Algol dims by more than a factor of three for 10 hours at a time, dwindling easily seen with the naked eye.

    "It seems that the first observation of a variable star was made 3,000 years earlier than was previously thought," said researcher Lauri Jetsu, an astronomer at the University of Helsinki.

    The Cairo Calendar describes how Wedjat, the Eye of Horus, regularly transformed from peaceful to raging, with good or bad influences on life. Horus was the patron god of kings in ancient Egypt. [Gallery: Sun Gods and Goddesses]

    "The eclipse seems to be linked with the lucky days, because it represents the pacification of the Eye of Horus," researcher Sebastian Porceddu, an astronomer and Egyptologist at the University of Helsinki, told LiveScience. "A bright Eye of Horus meant it is raging and a threat to mankind."

    Pinch of salt?

    In modern times, Algol actually dims every 2.867 days. The researchers suggest this discrepancy of 0.017 days — about 25 minutes — between ancient Egyptian and modern values for Algol's dimming may be due to changes Algol may have undergone in the past three millennia. Matter is apparently flowing from the dimmer member of this eclipsing binary to the brighter star, altering their orbit so that eclipses now take longer than they once did. If correct, this ancient Egyptian data could shed light on eclipsing binaries and the details of how such mass transfer might affect their orbits.

    "I believe that from now on, Egyptologists will be keeping an eye on possible references to Algol elsewhere," Porceddu said.

    Other scientists are intrigued by the idea, but remain skeptical.

    "I think it's an interesting idea — just how convincing it is is another issue," astrophysicist Peter Eggleton at Lawrence Livermore National Laboratory, who did not take part in this research, said in an interview.

    This pattern "does seem very plausibly attributed to Algol, and the suggestion that it has slowed down by a small amount over 3,000 years is not unreasonable," Eggleton said. "But you do have to take the idea with a pinch of salt — it's obviously difficult to pin down what people were really thinking 3,000 years ago."

    Choi, Charles. 2012. "Ancient Egyptian Calendar Reveals Earliest Record of 'Demon Star'". Live Science. Posted: May 31, 2012. Available online:

    Saturday, June 9, 2012

    Time flows uphill for remote Papua New Guinea tribe

    "HERE and now", "Back in the 1950s", "Going forward"... Western languages are full of spatial metaphors for time, and whether you are, say, British, French or German, you no doubt think of the past as behind you and the future as stretching out ahead. Time is a straight line that runs through your body.

    Once thought to be universal, this "embodied cognition of time" is in fact strictly cultural. Over the past decade, encounters with various remote tribal societies have revealed a rich diversity of the ways in which humans relate to time (see "Attitudes across the latitudes"). The latest, coming from the Yupno people of Papua New Guinea, is perhaps the most remarkable. Time for the Yupno flows uphill and is not even linear.

    Rafael Núñez of the University of California, San Diego, led his team into the Finisterre mountain range of north-east Papua New Guinea to study the Yupno living in the village of Gua. There are no roads in this remote region. The Yupno have no electricity or even domestic animals to work the land. They live with very little contact with the western world.

    Núñez and his colleagues noticed that the tribespeople made spontaneous gestures when speaking about the past, present and future. They filmed and analysed the gestures and found that for the Yupno the past is always downhill, in the direction of the mouth of the local river. The future, meanwhile, is towards the river's source, which lies uphill from Gua.

    This was true regardless of the direction they were facing. For instance, if they were facing downhill when talking about the future, a person would gesture backwards up the slope. But when they turned around to face uphill, they pointed forwards (Cognition, DOI: 10.1016/j.cognition.2012. 03.007).

    Núñez thinks the explanation is historical. The Yupno's ancestors arrived by sea and climbed up the 2500-metre-high mountain valley, so lowlands may represent the past, and time flows uphill.

    But the most unusual aspect of the Yupno timeline is its shape. The village of Gua, the river's source and its mouth do not lie in a straight line, so the timeline is kinked. "This is the first time ever that a culture has been documented to have everyday notions of time anchored in topographic properties," says Núñez.

    Within the dark confines of their homes, geographical landmarks disappear and the timeline appears to straighten out somewhat. The Yupno always point towards the doorway when talking about the past, and away from the door to indicate the future, regardless of their home's orientation. That could be because entrances are always raised, says Núñez. You have to climb down - towards the past - to leave the house, so each home has its own timeline.

    "This study is an important landmark," says Pierre Dasen, an anthropologist at the University of Geneva in Switzerland who was not involved in the work. "It demonstrates both universality of cognitive processes and a fascinating cultural difference."

    Lera Boroditsky of Stanford University in California agrees. "Each one of these discoveries isn't just telling us something about other people, it's telling us something about us," she says. "A lot of English speakers think that it's natural to think of time as a straight line. But that's an illusion. It doesn't have to be that way."

    Ananthaswamy, Anil. 2012. "Time flows uphill for remote Papua New Guinea tribe ". New Scientist. Posted: May 31, 2012. Available online:

    Friday, June 8, 2012

    Amelia Earhart Distress Call Details Emerge

    Dozens of previously dismissed radio signals were actually credible transmissions from Amelia Earhart, according to a new study of the alleged post-loss signals from Earhart's plane. The transmissions started riding the air waves just hours after Earhart sent her last inflight message. The study, presented on Friday at a three day conference by researchers of The International Group for Historic Aircraft Recovery (TIGHAR), sheds new light on what may have happened to the legendary aviator 75 years ago. The researchers plan to start a high-tech underwater search for pieces of her aircraft next July. "Amelia Earhart did not simply vanish on July 2, 1937. Radio distress calls believed to have been sent from the missing plane dominated the headlines and drove much of the U.S. Coast Guard and Navy search," Ric Gillespie, executive director of TIGHAR, told Discovery News. "When the search failed, all of the reported post-loss radio signals were categorically dismissed as bogus and have been largely ignored ever since," he added. Using digitized information management systems, antenna modeling software, and radio wave propagation analysis programs, TIGHAR re-examined all the 120 known reports of radio signals suspected or alleged to have been sent from the Earhart aircraft after local noon on July 2, 1937 through July 18, 1937, when the official search ended. They concluded that 57 out of the 120 reported signals are credible. "The results of the study suggest that the aircraft was on land and on its wheels for several days following the disappearance," Gillespie said. Earhart used radio transmissions on her last flight on July 2, 1937, during her record attempt to fly around the world at the equator. At 07:42 local time, as she flew toward the target destination, Howland Island in the Pacific, with her navigator Fred Noonan, Earhart called the Coast Guard cutter Itasca, stationed at Howland Island to support her flight. “We must be on you, but cannot see you -- but gas is running low. Have been unable to reach you by radio. We are flying at 1,000 feet,” she said. Earhart's final inflight radio message occurred a hour later, at 08:43. “We are on the line 157 337. We will repeat this message. We will repeat this on 6210 kilocycles. Wait,” she said. According to TIGHAR, the numbers 157 and 337 refer to compass headings -- 157 degrees and 337 degrees -- and describe a navigation line that passed not only Howland Island, the target destination, but also Gardner Island, now called Nikumaroro. This uninhabited atoll in the southwestern Pacific republic of Kiribati is where TIGHAR believes Earhart and Noonan landed safely and ultimately died as castaways. According to TIGHAR's hypothesis, Earhart would have used the aircraft's radio to make distress calls for several days until the plane was washed over the reef and disappeared before Navy searchers flew over the area. TIGHAR built a detailed catalog and analysis of all the reported post-loss radio signals, and selected the credible ones based on their frequencies. Transmissions from Earhart's Electra (NR16020) were possible on three primary frequencies: 3105 kHz, 6210 kHz and 500 kHz. For the latter, however, there were no reported post loss signals. On her world flight, Earhart transmitted on 3105 kHz at night, and 6210 kHz during daylight, using her 50-watt WE-13C transmitter. The Itasca transmitted on 3105 kHz, but did not have voice capability on 6210 kHz. Under favorable propagation conditions, it was possible for aircraft operating on the U.S. west coast at night to be heard on 3105 kHz in the central Pacific. Indeed, the Itasca reported hearing such signals on one occasion. There were three 50-watt Morse code radio stations in Nicaragua which could be heard on a receiver tuned to 3105 kHz, but the stations sent only code, not voice. Moreover, all transport aircraft in the area used assigned route frequencies, instead of 3105 kHz. "Therefore, other than Itasca, Earhart’s Electra was the only plausible central Pacific source of voice signals on 3105 kHz," said Gillespie. Although several of the analyzed post-loss signal reports were determined to be hoaxes, Gillespie ruled out the hypothesis of an illegal transmitter "given the numerous constraints militating against successfully perpetrating a signal transmission hoax." "We do not really have hoax transmissions but rather reports from people who, for whatever reason, claimed to have heard something they did not hear," Gillespie said. To make multiple transmissions, the Electra plane needed to run the right-hand, generator-equipped engine to recharge the batteries. "The safest procedure is to transmit only when the engine is running, and battery power is required to start the engine," said Gillespie. "To run the engine, the propeller must be clear of obstructions, and water level must never reach the transmitter." To verify the hypothesis that the plane landed on Nikumaroro's reef, TIGHAR researchers analyzed tidal condition on the island from 2 to 9 July 1937, the week following Earhart disappearance. It emerged that transmission of credible signals occurred in periods during which the water level on the reef was low enough to permit engine operation. According to Gillespie, at least four radio signals are of particular interest, as they were simultaneously heard by more than one station. The first signal, made when the pilot had been officially missing for just 5 hours, was received by the Itasca, and two other ships, the HMS Achilles, and the SS New Zealand Star. The Itasca logged “We hear her on 3105 now - very weak and unreadable/ fone” and asked Earhart to send Morse code dashes. The Achilles did not hear “very weak and unreadable” voice, but heard Itasca’s request and heard dashes in response. The SS New Zealand only heard the response dashes. In other cases, credible sources in widely separated locations in the U.S., Canada, and the central Pacific, reported hearing a woman requesting help. She spoke English, and in some cases said she was Amelia Earhart. In one case, on July 5, the U.S. Navy Radio at Wailupe, Honolulu heard a garbled Moorse code: “281 north Howland - call KHAQQ - beyond north -- won’t hold with us much longer -- above water -- shut off.” At the same time, an amateur radio operator in Melbourne, Australia, reported having heard a "strange” code which included KHAQQ, Amelia's call sign. According to Gillespie, the re-analysis of the credible post loss signals supports the hypothesis that they were sent by Earhart’s Electra from a point on the reef at Nikumaroro, about ¼ mile north of the shipwreck of the British freighter SS Norwich City. "The results of the study show a body of evidence which might be the forgotten key to the mystery. It is the elephant in the room that has gone unacknowledged for nearly seventy-five years," said Gillespie.

    Lorenzi, Rossella. 2012. "Amelia Earhart Distress Call Details Emerge". Live Science. Posted: June 4, 2012. Available online:

    Thursday, June 7, 2012

    Hidden treat: The Easter Island heads also have BODIES

    The enduring image in the public's mind of the mysterious heads on Easter Island is simply that - heads.

    So it comes as quite a shock to see the heads from another angle - and discover that they have full bodies, extending down many, many feet into the ground of the island.


    The Easter Island Statue Project has been carefully excavating two of 1,000-plus statues on the islands - doing their best to uncover the secrets of the mysterious stones, and the people who built them.

    Project director Jo Anne Van Tilburg said: 'Our EISP excavations recently exposed the torsos of two 7m tall statues.

    'Hundreds, perhaps thousands, of visitors to the island have been astonished to see that, indeed, Easter Island statues have bodies!

    'More important, however, we discovered a great deal about the Rapa Nui techniques of ancient engineering.'

    Among their discoveries, the team have discovered:

  • *The dirt and detritus partially burying the statues was washed down from above and not deliberately placed there to bury, protect, or support the statues
  • *The statues were erected in place and stand on stone pavements
  • *Post holes were cut into bedrock to support upright tree trunks
  • *Rope guides were cut into bedrock around the post holes
  • *Posts, ropes, stones, and different types of stone tools were all used to carve and raise the statues upright

    The remote island - one of the remotest in the world, tucked away in the South Pacific Ocean - was once home to a Polynesian population, whose history remains mysterious.

    They likely sailed to the islands in canoes - a 1,500-mile journey over the open waters, and then, once they landed, they began relentessly carving the stone statues.

    This led to their own downfall: By the time Europeans discovered the island in the 1700s, the population had decimated nearly all the trees in the island to help with the statue construction, and the knock-on effect on the island's ecology led to their decline.

    The team also discovered that ceremonies were certainly associated with the statues.

    On the project website, Van Tilburg said: 'We found large quantities of red pigment, some of which may have been used to paint the statues.

    'Finally, and perhaps most poignantly, we found in the pavement under one statue a single stone carved with a crescent symbol said to represent a canoe, or vaka.

    'The backs of both statues are covered with petroglyphs, many of which are also vaka. A direct connection between the vaka symbol and the identity of the artist or group owning the statue is strongly suggested.'

    Visit the official website.

    Wrenn, Eddie. 2012. "Hidden treat: The Easter Island heads also have BODIES".The Daily Mail. Posted: May 25, 2012. Available online:

  • Wednesday, June 6, 2012

    Huge Ancient Civilization's Collapse Explained

    The mysterious fall of the largest of the world's earliest urban civilizations nearly 4,000 years ago in what is now India, Pakistan, Nepal and Bangladesh now appears to have a key culprit — ancient climate change, researchers say.

    Ancient Egypt and Mesopotamia may be the best known of the first great urban cultures, but the largest was the Indus or Harappan civilization. This culture once extended over more than 386,000 square miles (1 million square kilometers) across the plains of the Indus River from the Arabian Sea to the Ganges, and at its peak may have accounted for 10 percent of the world population. The civilization developed about 5,200 years ago, and slowly disintegrated between 3,900 and 3,000 years ago — populations largely abandoned cities, migrating toward the east.

    "Antiquity knew about Egypt and Mesopotamia, but the Indus civilization, which was bigger than these two, was completely forgotten until the 1920s," said researcher Liviu Giosan, a geologist at Woods Hole Oceanographic Institution in Massachusetts. "There are still many things we don't know about them."

    Nearly a century ago, researchers began discovering numerous remains of Harappan settlements along the Indus River and its tributaries, as well as in a vast desert region at the border of India and Pakistan. Evidence was uncovered for sophisticated cities, sea links with Mesopotamia, internal trade routes, arts and crafts, and as-yet undeciphered writing.

    "They had cities ordered into grids, with exquisite plumbing, which was not encountered again until the Romans," Giosan told LiveScience. "They seem to have been a more democratic society than Mesopotamia and Egypt — no large structures were built for important personalitiess like kings or pharaohs."

    Like their contemporaries in Egypt and Mesopotamia, the Harappans, who were named after one of their largest cities, lived next to rivers.

    "Until now, speculations abounded about the links between this mysterious ancient culture and its life-giving mighty rivers," Giosan said.

    Now Giosan and his colleagues have reconstructed the landscape of the plain and rivers where this long-forgotten civilization developed. Their findings now shed light on the enigmatic fate of this culture.

    "Our research provides one of the clearest examples of climate change leading to the collapse of an entire civilization," Giosan said.

    The researchers first analyzed satellite data of the landscape influenced by the Indus and neighboring rivers. From 2003 to 2008, the researchers then collected samples of sediment from the coast of the Arabian Sea into the fertile irrigated valleys of Punjab and the northern Thar Desert to determine the origins and ages of those sediments and develop a timeline of landscape changes.

    "It was challenging working in the desert — temperatures were over 110 degrees Fahrenheit all day long (43 degrees C)," Giosan recalled.

    After collecting data on geological history, "we could reexamine what we know about settlements, what crops people were planting and when, and how both agriculture and settlement patterns changed," said researcher Dorian Fuller, an archaeologist with University College London. "This brought new insights into the process of eastward population shift, the change towards many more small farming communities, and the decline of cities during late Harappan times."

    Some had suggested that the Harappan heartland received its waters from a large glacier-fed Himalayan river, thought by some to be the Sarasvati, a sacred river of Hindu mythology. However, the researchers found that only rivers fed by monsoon rains flowed through the region.

    Previous studies suggest the Ghaggar, an intermittent river that flows only during strong monsoons, may best approximate the location of the Sarasvati. Archaeological evidence suggested the river, which dissipates into the desert along the dried course of Hakra valley, was home to intensive settlement during Harappan times.

    "We think we settled a long controversy about the mythic Sarasvati River," Giosan said.

    Initially, the monsoon-drenched rivers the researchers identified were prone to devastating floods. Over time, monsoons weakened, enabling agriculture and civilization to flourish along flood-fed riverbanks for nearly 2,000 years.

    "The insolation — the solar energy received by the Earth from the sun — varies in cycles, which can impact monsoons," Giosan said. "In the last 10,000 years, the Northern Hemisphere had the highest insolation from 7,000 to 5,000 years ago, and since then insolation there decreased. All climate on Earth is driven by the sun, and so the monsoons were affected by the lower insolation, decreasing in force. This meant less rain got into continental regions affected by monsoons over time." Eventually, these monsoon-based rivers held too little water and dried, making them unfavorable for civilization.

    "The Harappans were an enterprising people taking advantage of a window of opportunity — a kind of "Goldilocks civilization," Giosan said.

    Eventually, over the course of centuries, Harappans apparently fled along an escape route to the east toward the Ganges basin, where monsoon rains remained reliable.

    "We can envision that this eastern shift involved a change to more localized forms of economy — smaller communities supported by local rain-fed farming and dwindling streams," Fuller said. "This may have produced smaller surpluses, and would not have supported large cities, but would have been reliable."

    This change would have spelled disaster for the cities of the Indus, which were built on the large surpluses seen during the earlier, wetter era. The dispersal of the population to the east would have meant there was no longer a concentrated workforce to support urbanism.

    "Cities collapsed, but smaller agricultural communities were sustainable and flourished," Fuller said. "Many of the urban arts, such as writing, faded away, but agriculture continued and actually diversified."

    These findings could help guide future archaeological explorations of the Indus civilization. Researchers can now better guess which settlements might have been more significant, based on their relationships with rivers, Giosan said.

    It remains uncertain how monsoons will react to modern climate change. "If we take the devastating floods that caused the largest humanitarian disaster in Pakistan's history as a sign of increased monsoon activity, than this doesn't bode well for the region," Giosan said. "The region has the largest irrigation scheme in the world, and all those dams and channels would become obsolete in the face of the large floods an increased monsoon would bring."

    Choi, Charles. 2012. "Huge Ancient Civilization's Collapse Explained". Discovery News. Posted: May 29, 2012. Available online: