Thursday, February 4, 2016

Penn, Notre Dame researchers mapping genetic history of the Caribbean

In the island chain called the Lesser Antilles, stretching from the Virgin Islands south to Trinidad and Tobago, a team of researchers lead by Theodore Schurr, an anthropology professor in the University of Pennsylvania's School of Arts & Sciences, is solving a generations-old mystery: Do indigenous communities still exist in the Caribbean region today?

"We're really trying to connect the dots and understand the migration, the flow of people in and out of the region," said Schurr, who has worked in the area since 2012 and on similar genetics projects for more than two decades. "Each island seems to have its distinct history."

Schurr and his team, which includes Jill Gaieski of Penn's Perelman Center for Advanced Medicine, Miguel Vilar, a Penn postdoc at the time of the research and now at the National Geographic Society, and Jada Benn Torres from Notre Dame University, focused their research on DNA samples from 88 participants in the First Peoples Community in Trinidad and the Garifuna people in St. Vincent.

By looking at mitochondrial DNA, Y-chromosomes and autosomal markers, three parts of the genome known for containing what Schurr described as "signals" of indigenous ancestry, the researchers eventually detected 42 percent indigenous ancestry from the maternal side, 28 percent from the paternal side.

Mitochondrial DNA comes from the mother only, regardless of the number of generations considered. The Y-chromosome is the paternal correlate, or the complement to mitochondrial DNA, passed from fathers to sons. Autosomes, only recently included in this area of research, do not reveal specific details about maternal and paternal lineage but give an overall picture of the genetic contributions from ancestors traced through both the mother's and father's sides of the family.

"In the case of the mitochondrial DNA and the Y-chromosome," Schurr said, "we know the markers that define those lineages commonly seen in indigenous populations of the Americas."

During the past three years, Schurr and his colleagues have done fieldwork in St. Vincent and Trinidad. "These communities are not passive in this whole process; they're actively exploring their own ancestry," said Schurr. "They're also trying to establish the fact that they have indigenous ancestry, that they are the descendants of the original inhabitants. They're reclaiming that history."

The work began as part of the Genographic Project, which was started and initially funded by the National Geographic Society. It is a multi-institutional endeavor with the goal of mapping the globe genetically. A dozen research labs around the world analyzed DNA samples from indigenous and traditional communities, and a public participation component of the project allowed anyone to submit DNA for analysis in the database. Schurr's contribution involved indigenous communities of the Americas.

Expanding into parts of the Caribbean made sense. "It was an opportunity to actually add new information about an area that is relatively well described archaeologically but not so much so genetically," he said.

Schurr has already completed a similar study in Puerto Rico and recently began a larger project in the Dominican Republic.

Immersion in these communities has been eye opening, he said.

"You don't fully appreciate what's happening on the ground until you're there -- not only meeting people and getting to know them and their perspectives, their history, but absorbing details about the environment, the climate, how people make a living, the current state of economic development," he added. "You learn about the early colonial history of these islands as well as indigenous perspectives on this history."
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Reference:

EurekAlert. 2016. “Penn, Notre Dame researchers mapping genetic history of the Caribbean”. EurekAlert. Posted: November 5, 2015. Available online: http://www.eurekalert.org/pub_releases/2015-11/uop-pnd110515.php

Wednesday, February 3, 2016

Does religion make kids less generous?

Religious parents are more likely to describe their children as empathetic and concerned about justice than are non-religious parents. But, new evidence reported in the Cell Press journal Current Biology on November 5 suggests that the opposite is in fact true.

In the study, children growing up in households that weren't religious were significantly more likely to share than were children growing up in religious homes. The findings support the notion that the secularization of moral discourse may serve to increase rather than decrease human kindness, the researchers say.

"Some past research had demonstrated that religious people aren't more likely to do good than their nonreligious counterparts," said Jean Decety of the University of Chicago. "Our study goes beyond that by showing that religious people are less generous, and not only adults but children too."

To examine the influence of religion on the expression of altruism, Decety and his colleagues asked more than 1,100 children between the ages of five and twelve from the US, Canada, Jordan, Turkey, South Africa, and China to play a game in which they were asked to make decisions about how many stickers to share with an anonymous person from the same school and a similar ethnic group. Most of the children came from households that identified as Christian, Muslim, or not religious. The study also included smaller numbers of children from Jewish, Buddhist, Hindu, and agnostic homes.

The children became more generous with age, consistent with earlier studies. But their religious rearing environment also fundamentally shaped their altruistic tendencies, with more-religious children showing less generosity. Importantly, the researchers report, children who were the most altruistic came from atheist or non-religious families.

The data also show that religious children judged interpersonal harm as being meaner and deserving of harsher punishment than did children from non-religious households. Those findings are consistent with past research in adults showing that religiousness is directly related to increased intolerance for and punitive attitudes toward interpersonal offenses, including the probability of supporting harsh penalties.

The results might be explained in part by "moral licensing," a phenomenon in which doing something "good"--in this case practicing a religion--can leave people less concerned about the consequences of immoral behavior, the researchers say. They also come as a timely reminder that religion and morality are not one and the same.

"A common-sense notion is that religiosity has a positive association with self-control and moral behaviors," Decety said. "This view is unfortunately so deeply embedded that individuals who are not religious can be considered morally suspect. In the United States, for instance, non-religious individuals have little chance to be elected to a high political office, and those who identify as agnostic and atheist are considered to be less trustworthy and more likely to be amoral or even immoral. Thus, it is generally admitted that religion shapes people's moral judgments and prosocial behavior, but the relation between religiosity and morality is actually a contentious one, and not always positive."

Decety says he is now in the process of expanding the work to include children of ages four to eight in 14 countries--Canada, China, Cuba, Colombia, Argentina, Chile, South Africa, Turkey, Jordan, Taiwan, Tanzania, Ethiopia, Norway, and Mexico.
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Reference:

EurekAlert. 2016. “Does religion make kids less generous?”. EurekAlert. Posted: November 5, 2015. Available online: http://www.eurekalert.org/pub_releases/2015-11/cp-drm102915.php

Tuesday, February 2, 2016

Mysterious Symbols in Kazakhstan: How Old Are They, Really?

Sprawling earthen swastika designs, crosses and rings that cover part of Kazakhstan are becoming a little less mysterious: Archaeologists have found and investigated 60 of these symbols, called geoglyphs, and determined when they were created and what their potential function might have been.

The Kazakhstan geoglyphs, described at an archaeology conference in Istanbul and reported by Live Science last year, range in size from 90 to 400 meters (295 to 1,312 feet) across — longer than a commercial aircraft.

The earthen works take on various geometric shapes, including squares, crosses, rings and a swastika. In ancient times, the swastika was a common design with no political undertones. The geoglyphs were shaped from earth.

Using a dating technique called optically stimulated luminescence (OSL), the archaeologists recently found that the structures were constructed starting around 2,800 years ago. They were built at the beginning of Kazakhstan's "iron age," when iron tools and weapons gradually replaced those made of bronze, said archaeologists Andrew Logvin and IrinaShevnina, both of Kostanay University in Kazakhstan.

The astronauts aboard the International Space Station may try to take images of the geoglyphs, Melissa Higgins, an earth science and remote sensing scientist at NASA, said in a phone conversation with Live Science. Whether the crew is able to take images depends on their schedule and whether sun elevation will allow them to capture photos of the geoglyphs, she said.   

A New York Times report published on Oct. 30 suggested the geoglyphs (which the Times called "ancient earthworks") date as far back as 8,000 years — which would make them older than any other such geoglyphs, including the famous Nazca Lines of Peru, which date to between 200 B.C. and A.D. 500.

However, following the publication of that story, the three archaeologists who did the research — Logvin and Shevnina, as well as Giedre Motuzaite Matuzeviciute, a postdoctoral fellow at Vilnius University in Lithuania —disputed the report, saying the geoglyphs are not nearly that old.

Live Science contacted all three of them last weekend, after the New York Times story was published, to find out if the date, and other details of the story, were accurate. The claim that these symbols date back as far as 8,000 years is "not supported by any evidence at all," Matuzeviciute said. The OSL dating technique the team used "gave ca. 800 B.C. and nothing earlier," she said. 

In the time since, The Times has made changes (compare the articlebefore and after) to the story to clarify that the claim that the geoglyphs are 8,000 years old does not come from the archaeologists doing the research but rather from a "separate scholarly report linking artifacts from the Mahandzhar culture (7000 B.C. to 5000 B.C.) to other figures, suggesting a date as early as 8,000 years ago for the oldest." The Times does not specify who wrote this report or where it was published. The Times writer, in response to a Live Science inquiry, said he stands by the accuracy of the article.

So far, the archaeologists can confirm the existence of 60 such geoglyphs in Kazakhstan. They suspect more will be found, but they have yet to find 260 of the earthen designs, as was reported by the Times, Logvin and Shevnina said.

Though the purpose of the geoglyphs is not known, excavations at the geoglyphs have yielded the remains of structures and hearths that may have been used as sanctuaries, Logvin and Shevnina said. They also noted that the geoglyphs might have been used by tribes to mark territory.

Logvin and Shevnina said that, earlier this year, they received a grant from Kazakhstan's Ministry of Science that will aid in their research.
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Reference:

Jarus, Owen. 2016. “Mysterious Symbols in Kazakhstan: How Old Are They, Really?”. Live Science. Posted: November 5, 2015. Available online: http://www.livescience.com/52700-mysterious-geoglyphs-in-kazakhstan-revealed.html

Monday, February 1, 2016

Environment and climate helped shape varied evolution of human languages

A new study reveals that the evolution of differences between human language's sound systems is partly linked to climatic or ecological conditions.

It's well known that gradual adaptation to the environment shaped the development of human bodies and brains, but recent work by an international group of researchers suggests that the variations in human linguistic evolution also reflect adaptations to the local ecological conditions.

The researchers, who hail from the University of New Mexico and Laboratoire Dynamique du Langage-CNRS, France, have conducted an extensive study to examine the relationship between the sound structures of a worldwide sample of human languages and climatic and ecological factors including temperature, precipitation, vegetation and geomorphology.

The study will be presented at the 170th Meeting of the Acoustical Society of America (ASA), being held Nov. 2-6, 2015, in Jacksonville, Fla. Their results show a correlation between ecological factors and the ratio of sonorant segments, which are produced by uninterrupted airflow, to obstruent segments, which are formed by obstructing airflow, in the examined languages. This supports the hypothesis that acoustic adaptation to the environment plays a role in the evolution of human languages.

"We believe this work is by far the most extensive and careful work on a possible link between specific aspects of human languages' sound patterns and environmental factors," said Ian Maddieson, the primary researcher and an adjunct professor in the Department of Linguistics at the University of New Mexico.

"We find that the number of distinct consonants and the degree to which consonants cluster together in syllables correlate with mean annual precipitation, mean annual temperature, the degree of tree cover and the geographic elevation and 'mountain-ness' ('rugosity') of the area in which they are traditionally spoken," he said. "Both the number of distinct consonants and their distribution in syllabic structures are lower where tree cover and temperature are higher."

Both of these factors tend to make the transmission of higher frequencies less reliable. According to Maddieson, this could explain why languages spoken by people in tropical areas tend to make more vowels in their languages, as these are distinguished by differences in the lower frequencies. Additionally, by using simpler syllable structures, the vowels occur more often in the stream of spoken language.

Maddieson said that their findings offer support for an application of the Acoustic Adaptation Hypothesis -- which argues that species adapt their acoustic signals to optimize sound transmission in the environment they live in -- to human languages. The hypothesis was first proposed by E.S. Morton in 1975 in relation to the calls of 177 bird species. Morton suggested that birds in forested areas tend to sing at lower frequencies than birds living in open areas in order to enhance the effectiveness of transmission of the signal in the specific environment they live in. More recent work has shown that birds of the same species adapt their calls to make them more effective against the background of modern urban noise pollution.

To explore the relevance of the Acoustic Adaptation Hypothesis to the evolution of human languages, Maddieson's team correlated phonological data on languages from the Lyon-Albuquerque Phonological Systems Database (LAPSyD) with climatic and ecological data from the International Steering Committee for Global Mapping.

Major world languages spoken such as English, Mandarin Chinese and Spanish were excluded, as they may not show any detectable relationship between environmental factors and linguistic traits. After other exclusions, such as cases where data was missing or where language names were ambiguous, 628 languages indigenous to all parts of the world were included in the final analysis.

"The transmission of sound waves consists of the propagation of small pressure differences through space in a medium such as air. For the most faithful propagation of sound waves, the medium needs to be uniform, otherwise some distortions will occur," Maddieson explained.

In an area with dense vegetation, the paths of transmission are not uniform. Some sound waves are reflected backwards by the vegetation, while others are diverted sideways, leading to signal degradation and ineffective transmission. Additionally, sound signals containing very rapid changes, or high frequencies -- such as the consonants /p, t, k/ -- are more affected by dense vegetation than sound signals with steady-state or low-frequency characters, such as vowels.

"That could explain why languages in areas with greater tree cover tend to be less 'consonant-heavy,'" Maddieson said. "Environments in which higher frequencies are less faithfully transmitted may favor greater use of sounds characterized by low frequencies, that is, more sonorous sounds."

Maddieson noted that vegetation is not the only ecological factor affecting human sound transmission, as warm dry air can generate ripples in the air that break up the coherence of high-frequency sound transmission, and rough terrain can degrade high-frequency signals. Other factors such as temperature, wind and rain play roles in shaping human languages in different areas as well.

Their analysis suggests that total annual precipitation, mean annual temperature and rugosity all contribute to explaining how consonant-heavy a language is. According to Maddieson, these factors account for almost a quarter of the variation in how 'consonant-heavy' a language is (see figure).

The researchers' next step is to study a large sample of spoken language recordings rather than summary data on inventories and syllable structures to see if ecological factors could predict the proportion of sonorant segments per unit time in spoken languages.

Presentation #3aSC1, "Human spoken language diversity and the acoustic adaptation hypothesis" by Ian Maddieson, will be take place on Wednesday, Nov. 5, 2015, at 9:00 AM in Grand Ballroom 6. The abstract can be found by searching for the presentation number here:https://asa2015fall.abstractcentral.com/planner.jsp
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Reference:

EurekAlert. 2016. “Environment and climate helped shape varied evolution of human languages”. EurekAlert. Posted: November 4, 2015. Available online: http://www.eurekalert.org/pub_releases/2015-11/asoa-eac102815.php

Sunday, January 31, 2016

Early proto-porcelain from China likely made from local materials

Early Chinese proto-porcelain was likely made from materials gathered locally, according to a study published November 4, 2015 in the open-access journal PLOS ONE by Yu Li from the Fudan University, Shanghai, China, and colleagues.

Researchers excavated the Piaoshan kiln site in June 2012 and found evidence that the sites contents may be the earliest known Chinese proto-porcelain, a type of early Chinese porcelain. Based on the decorated patterns on the impressed stoneware and proto-porcelain sherds, the site is estimated to date to the late Xia (2070-1600 BC), the first dynasty of China. The authors of this study conducted proton-induced X-ray emission analyses of 118 proto-porcelain and 35 impressed stoneware sherds (pottery fragments) from Piaoshan and five subsequent kiln sites in the vicinity.

"The chemical composition of proto-porcelain samples from Piaoshan kiln site is studied for the first time in history", said Yu Li. "The research clearly show the relationship of inheritance of early Chinese proto-porcelain, and fill the large gaps in knowledge regarding the origin of Chinese proto-porcelain."

The authors found that impressed stoneware and proto-porcelain samples from the six kiln sites had distinct chemical profiles. This may indicate that the raw materials at each site were procured locally. They also found what may be one of the earliest attempts at applying artificial calcium-based glaze by mixing woody plant ashes with increased calcia-potash ratios into the glaze formula, the ashes likely leftover from firewood used to heat the kilns.
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Reference:

EurekAlert. 2016. “Early proto-porcelain from China likely made from local materials”. EurekAlert. Posted: November 4, 2015. Available online: http://www.eurekalert.org/pub_releases/2015-11/p-epf102915.php

Saturday, January 30, 2016

Buried in ash, ancient Salvadoran village shows images of daily life

Village of Ceren so well preserved that footprints and finger marks remain

A continuing look at a Maya village in El Salvador--frozen in time by a blanket of volcanic ash from 1,400 years ago--shows the farming families who lived there went about their daily lives with virtually no strong-arming by the elite royalty lording over the valley.

Instead, archaeological evidence indicates significant interactions at the village of Ceren took place among families, village elders, craftspeople and specialty maintenance workers. This research comes from a new University of Colorado Boulder (CU-Boulder) study, funded by the National Science Foundation (NSF).

Ceren is the best-preserved ancient Maya village in all of Latin America. In A.D. 660, the village was blasted by toxic gas, pummeled by lava bombs and then choked by a 17-foot layer of ash falling over several days after the Loma Caldera volcano, less than half a mile away, erupted.

Discovered in 1978 by CU-Boulder anthropology Professor Payson Sheets, Ceren has been called the "New World Pompeii." The degree of preservation is so great researchers can see marks of finger swipes in ceramic bowls, and human footprints in gardens that host ghostly ash casts of corn stalks. Researchers have also uncovered thatched roofs, woven blankets and bean-filled pots.

Some Maya archaeological records document "top-down" societies, where the elite class made most political and economic decisions, at times exacting tribute or labor from villages, said Sheets. But at Ceren, the villagers appear to have had free reign regarding their architecture, crop choices, religious activities and economics.

"This is the first clear window anyone has had on the daily activities and the quality of life of Maya commoners back then," said Sheets, who is directing the excavation. "At Ceren we found virtually no influence and certainly no control by the elites."

A paper on the subject appears in the current issue of Latin American Antiquity published by the Society for American Archaeology. The 10-acre Ceren research area was declared a UNESCO World Heritage Site in 1993.

Ceren is believed to have been home to about 200 people. Researchers have excavated 12 buildings, including living quarters, storehouses, workshops, kitchens, religious buildings and a community sauna. There are dozens of unexcavated structures, and perhaps even another settlement or two under the Loma Caldera volcanic ash, which covers an area of roughly two square miles, Sheets said. Thus far, no bodies have been found, an indication a precursor earthquake may have given residents a running start just before the eruption.

The only relationship Ceren commoners had with Maya elite was indirect, through public marketplace transactions in El Salvador's Zapotitan Valley. There, Ceren farmers likely swapped surplus crops or crafts for coveted specialty items like jade axes, obsidian knives and colorfully decorated polychrome pots, all of which elites arranged to have brought to market from a distance. Virtually every Ceren household had a jade axe--which is harder than steel--used for tree cutting, building and woodworking.

"The Ceren people could have chosen to do business at about a dozen different marketplaces in the region," said Sheets. "If they thought the elites were charging too much at one marketplace, they were free to vote with their feet and go to another."

One of the excavated community buildings has two large benches in the front room, which Sheets believes were used by village elders when making decisions. One decision would have involved organizing the annual crop harvest festival, a celebratory eating and drinking ritual that appears to have been underway at Ceren when the Loma Caldera volcano abruptly blew just north of the village, said Sheets.

He believes the villagers fled south, perhaps along a white road leading away from the village discovered under 15 feet of ash in 2011. The elevated road, known as a sacbe (SOCK-bay), is about 2 meters wide and made from white tightly packed volcanic ash, with drainage ditches along each edge. The sacbe appears to split in the village and lead toward the plaza and two religious structures: the large ceremonial building and a second, smaller structure used by a female shaman.

Unique research

"There are two aspects that make this project unique," said John Yellen, NSF program manager for the Ceren excavations. "The first is the incredible degree of preservation at Ceren, which captures in such detail a moment in time. The second is the perseverance and ingenuity of Dr. Sheets, who devised effective techniques to address a broad range of questions involving Ceren's agricultural practices and its social organization."

Prior to the discovery of Ceren's sacbe, such "white way" roads--which often connected temples, plazas and towns and had strong practical, political and spiritual connotations--were known only from Mexico's Yucatan Peninsula and all were lined on each side with paving stones, unlike the Ceren sacbe, said Sheets.

Measurements with an instrument known as a penetrometer indicated the sacbe was extraordinarily hard. This was, in part, because villagers must have vigorously pounded sections of the sacbe with heavy objects over a period of days, he said. In addition, tiny, angular grains of the ash, or tephra used to build the sacbe lock together in a tight matrix when packed down under moist conditions. The center of the sacbe was slightly grooved, an indication people walked single file as they headed to their crop fields or perhaps traveled to and from the nearby town of San Andres.

"The western canal of the sacbe was crisp and well formed and had apparently been worked on just days before the eruption," said Sheets. "But it looks like the workers hadn't gotten around to maintaining the eastern canal before the volcanic event."

The team, which has dug 10 test pits so far in an attempt to trace the path of the sacbe from Ceren south, found several dozen footprints on its outer, softer edges. "More than half of the footprints were headed south away from the village, away from the danger," Sheets said. "I think at least some of them were left by people fleeing the eruption."

Who built and maintained the sacbe--now known to stretch at least 150 meters from the village and may well go all the way to San Andres--is still a mystery. "We think the work was done on the household level with multiple families involved, perhaps supervised by village elders," said Sheets.

There also is evidence that residents of particular households at Ceren were responsible for the upkeep of certain community structures, said Sheets. One household, for example, contained an inordinate amount of pots and firewood that the researchers speculated were used during activities in the domed community sauna building. That sweat bath, which could comfortably seat about a dozen people, had a central firebox where water was poured to create the desired steam and heat, Sheets said.

In 2009, Sheets and his team discovered intensively cultivated manioc (cassava) fields at Ceren. It was the first and only evidence of intense manioc cultivation at any New World archaeology site. Sheets and others believe such large manioc crops could have played a vital role in feeding indigenous societies living throughout tropical Latin America. Today, dried manioc powder is used in the region to make tortillas and tamales, and fermented manioc is used to make alcoholic beverages.
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Reference:

EurekAlert. 2016. “Buried in ash, ancient Salvadoran village shows images of daily life”. EurekAlert. Posted: November 3, 2015. Available online: http://www.eurekalert.org/pub_releases/2015-11/nsf-bia110315.php

Friday, January 29, 2016

Revealing the mysteries of the Maya script

EPFL researchers have come up with an algorithm to analyze Mayan writing. This project could one day contribute to translating this complex and still partially unknown language.

While some five million people still speak a language that evolved out of Mayan civilization in South America, the written language has suffered a different fate. The secrets of the classical Maya were lost with the destruction of most works during the Spanish conquest in the 16th century. Only three codices have been preserved, and they are in museums and institutions in Paris, Dresden and Madrid. These documents contain precious data for the researchers who are seeking to discover the secrets of this pre-Columbian writing, much of which remains obscure (10 to 15% of the symbols are not known). Researchers at Idiap, a research institute affiliated with EPFL and with the new Digital Humanities Laboratory of the College of Humanities, are harnessing the power of computers to help archeologists and epigraphers make significant progress in their work. Creative writers The researchers, working closely with the Maya writing specialists, have analyzed thousands of hieroglyph signs, which are symbols that represent a sound, or also a meaning. Maya texts are often written in the form of blocks. A block could contain one or multiple glyphs, representing a sound, a word or even an entire sentence. "Each image tells a story," said Rui Hu, a researcher working on Social Computing at Idiap. "Sometimes we can guess their meaning with the help of people who still speak this language today, and also by using glossaries." The task is particularly difficult because the hieroglyphs are difficult to decipher in the historical documents owing to their age and state of deterioration. What's more, pre-Columbian writers sometimes drew the symbols in different and creative ways, varying by era and location. And then there are those symbols that look like each other yet mean something completely different.

A real conundrum for archeologists and epigraphers, who still spend a significant amount of time poring over catalogs to identify each symbol. Thanks to the work of the Idiap researchers and the involvement of Maya writing specialists from Bonn University in Germany, high quality representations of the hieroglyphs found in the three known works have now been created and will be catalogued digitally. The researchers will then be able to use this tool to quickly identify a given hieroglyph and its meaning, and to see, for example, what the most common combinations of symbols observed in the same 'block' of text are. "This research is of great interest to mayanists, given the potential of such novel multidisciplinary approaches for overcoming obstacles resulting from applying more traditional methods", said Carlos Pallán Gayol, researcher at Bonn University.

This interdisciplinary project with the contribution of the University of Geneva will eventually lead to an online database that the scientific community will be able to use to research, compare and annotate texts in the quest to expand our knowledge of Mayan writing and iconography. "By combining the work of the Maya experts with IT-based tools, we can make fascinating progress," said Rui Hu. Progress that may someday lead to machine translation – something like Google Translate for historians.
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Reference:

Bourquenoud, Sarah. 2016. “Revealing the mysteries of the Maya script”. Phys.Org. Posted: November 2, 2015. Available online: http://phys.org/news/2015-11-revealing-mysteries-maya-script.html