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WASHINGTON UNIVERSITY IN ST. LOUIS—First domesticated 10,000 years ago in the Fertile Crescent of the Middle East, wheat and barley took vastly different routes to China, with barley switching from a winter to both a winter and summer crop during a thousand-year detour along the southern Tibetan Plateau, suggests new research from Washington University in St. Louis.
“The eastern dispersals of wheat and barley were distinct in both space and time,” said Xinyi Liu, assistant professor of archaeology in Arts & Sciences, and lead author of this study published in the journal PLOS One.
“Wheat was introduced to central China in the second or third millennium B.C., but barley did not arrive there until the first millennium B.C.,” Liu said. “While previous research suggests wheat cultivation moved east along the northern edge of the Tibetan Plateau, our study calls attention to the possibility of a southern route (via India and Tibet) for barley.”
Based on the radiocarbon analysis of 70 ancient barley grains recovered from archaeological sites in China, India, Kyrgyzstan and Pakistan, together with DNA and ancient textual evidence, the study tackles the mystery of why ancient Chinese farmers would change the seasonality of a barley crop that originated in a latitudinal range similar to their own.
The answer, Liu explains, is that barley changed from a winter to summer crop during its passage to China, a period in which it spent hundreds of years evolving traits that allowed it to thrive during short summer growing seasons in the highlands of Tibet and northern India.
“Barley arrives in central China later than wheat, bringing with it a degree of genetic diversity in relation to flowering time responses,” Liu said. “We infer such diversity reflects preadaptation of barley varieties along that possible southern route to seasonal challenges, particularly the high altitude effect, and that led to the origins of eastern spring barley.”
Liu’s research on the dispersal of wheat and barley cultivation adds a new chapter to our understanding of prehistoric food globalization, a process that began about 5000 B.C. and intensified around 1500 B.C. This ongoing research traces the geographic paths and dispersal times of crops and cultivation systems that expanded across Eurasia and eventually worldwide, from points of origination in North Africa and West, East and South Asia. The eastern expansion of wheat and barley is a key story in this process.
In the hot, arid southwest Asian region where wheat and barley were first domesticated, they were grown between autumn and subsequent spring to complete their life cycles before arrival of summer droughts. These early domesticated strains included genes carried over from wild grasses that triggered flowering and grain production as days grew longer with the approach of summer.
Because of this spring-flowering life cycle, early domesticated varieties of wheat and barley were poorly suited for cultivation in northern European climates with severe winters and a different day length pattern. Previous research by the second author in this study, Diane Lister, a postdoctoral research associate at the University of Cambridge, has shown that barley and wheat adapted to European climates by evolving a mutation that switched off the genes that made flowering sensitive to increases in day length, allowing them to be sown in spring and harvested in fall.
Liu’s study shows that barley evolved similar mutations on its way to China as farmers pushed its cultivation high into the mountains of the Tibetan Plateau. By the time barley reached central China, its genetic makeup had been altered so that flowering was no longer triggered by day length, allowing it to be planted in both spring and fall.
The ancient movement of wheat and barley cultivation into China offers two distinct stories about the adaption of newly introduced crops into an existing agrarian/culinary system, Liu said.
Ancient wheat that traveled to China along Silk Road routes also was genetically modified by farmers who selected strains that produced small-sized grains more suited to a Chinese cuisine that prepared them by boiling or steaming the whole grains. Larger wheat grains evolved in Europe where wheat was traditionally ground for flour.
Along the southern migration route for barley, the main story is the flowering time—changed by farmers to gain control over the seasonal pressures of high-altitude cultivation, Liu said.
Recovery of these ancient grains has become more routine in the last decade as scholars mastered a flotation technique that allows the separation of seeds and other minute biological material from excavated dirt immersed in a bucket of water. This approach, pioneered in China by the third author of this study, Zhijun Zhao, a professor of archaeology at the Chinese Academy of Social Sciences, has transformed the understanding of ancient farming in China.
The PLOS One findings reflect the contributions of 26 co-authors, including archaeologists who recovered the grains and those who analyzed them at leading archaeobotanical laboratories in the U.S., U.K., China and India. The team also includes leading experts for barley archaeogenetics, radiocarbon analysis and agricultural history around the globe.
“We’ve recently realized how much prehistoric crops moved around, on a scale much greater than anyone had envisaged,” said senior co-author Martin Jones, the George Pitt-Rivers Professor of Archaeological Science at Cambridge. “An intensive study of chronology, genetics and crop records now reveals how those movements laid the agrarian foundations of Bronze Age civilizations, enabling the control of seasons, and opening the way for rotation and multi-cropping.”

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photo: Prof Gary Lee Todd

photo: Prof Gary Lee Todd

 

Original Article:

arstechnica.co.uk

ByCATHLEEN O’GRADY (US) –

 

Bones and burial grounds point male children getting better-quality food.

Around 7,000 years ago in China’s Central Plains, the Yangshao culture began to flourish along the Yellow River. It was another example of the same widespread Neolithic culture that was also emerging in Europe around the time, with new developments in pottery and agriculture. In China, it dominated the region for approximately 2,000 years.

Yangshao remains have offered a team of international researchers insight into an interesting question: did gender differences change alongside agricultural practices? They argue that gender inequality emerged along with the new crops among the Yangshao. The archaeological data has some interesting signs, but it’s possible that the researchers are overstating their case: the only evidence they have is of inequality in people’s diets, which doesn’t tell us much about the structure of inequality of societies.

Millet cereals were domesticated in the region as early as 10,000 years ago and were the primary crop of Yangshao cultures. Wheat, barley, and soybeans were introduced to the region after the end of Yangshao, around 4,000 years ago, although archaeological traces of them remain low for centuries. According to historical records, they were thought to be inferior foods, suitable only for protecting the poor against famine. That only changed around 2,000 years ago, when improved technological methods made it easier to refine them.

Agricultural changes aren’t only reflected in artifacts; they show up in excavated bones, too. Millet uses a type of photosynthesis that differs from the vast majority of plants, and it’s the only domesticated plant in Early China to use this type of photosynthesis. The result of this is that the carbon signature in the bones of people who ate primarily millet looks different from that of people who ate other plants. Nitrogen traces in bones can point to the quantity of animal products in an individual’s diet.

The researchers compared Yangshao bones with remains from the Bronze Age Eastern Zhou Dynasty, which lasted from 771 to 221 BC. In the Eastern Zhou bones, they found evidence that men and women were eating different diets: men’s bones had evidence of higher consumption of animal products and millet, while women’s bones showed evidence of higher consumption of the more recent (and scorned) crops of wheat, barley, and soy. The Yangshao bones, on the other hand, generally didn’t show a significant difference, with the exception of one of the five sites studied. This suggests that “meals were no longer shared at the household level during Eastern Zhou,” the authors write.

On its own, this is not evidence of a bias favoring males. There could be cultural reasons for a gender-based split in diet that weren’t actively bad for women—although the fact that women were eating more of the food that was considered low quality is a bit telling.

But other strands of evidence corroborate the inequality story: women’s bones from Eastern Zhou, but not Yangshao, showed more signs of childhood malnutrition, and size differences between the sexes increased from Yangshao to Eastern Zhou. Both of these signs indicate that male children had better quality food, pointing to greater parental investment in male children. And female graves in Eastern Zhou had fewer burial items and were less likely to have a coffin than male graves, while again, Yangshao graves were more egalitarian.

It’s an interesting result, but it’s always a mistake to draw too many parallels with modern society from archaeological research. It’s also not clear that this is really evidence of the first emergence of gender inequality in this region of China.

It is evidence of a massive cultural change in how the genders related to each other, certainly. But food-based inequality isn’t the only kind of gender inequality that a society might practice—there are plenty of inarguably patriarchal modern societies where families eat meals together. It’s entirely possible that Yangshao did have inequality, but that it took a different shape and would have left a different kind of archaeological presence.

An open question is how the change in gender practices and agriculture are interwoven. Did the change in agriculture itself lead to the change in gender norms? The causal story is likely to be complicated, and the authors of the paper steer clear of suggesting that one led to the other, but the relationship between them is something that future research can hopefully illuminate.

PNAS, 2016. DOI: 10.1073/pnas.1611742114 (About DOIs).

This post originated on Ars Technica

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Right: Photograph during excavation exhibiting excellent dry preservation of plant remains Left: A well-preserved, desiccated barley grain found at Yoram Cave Credit: Uri Davidovich

Right: Photograph during excavation exhibiting excellent dry preservation of plant remains Left: A well-preserved, desiccated barley grain found at Yoram Cave Credit: Uri Davidovich

 

Original Article:

popular-archaeology.com

 

BAR-ILAN UNIVERSITY—An international team of researchers has succeeded for the first time in sequencing the genome of Chalcolithic barley grains. This is the oldest plant genome to be reconstructed to date. The 6,000-year-old seeds were retrieved from Yoram Cave in the southern cliff of Masada fortress in the Judean Desert in Israel, close to the Dead Sea. Genetically, the prehistoric barley is very similar to present-day barley grown in the Southern Levant, supporting the existing hypothesis of barley domestication having occurred in the Upper Jordan Valley.

Members of the research team are from the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK) in Gatersleben, Germany; Bar-Ilan University in Ramat Gan, Israel; Hebrew University, Jerusalem, Israel; the Max Planck Institute for the Science of Human History in Jena, Germany; and the University of Haifa, Israel; The James Hutton Institute, UK; University of California, Santa Cruz, USA; University of Minnesota St. Paul, USA; University of Tübingen, Germany.

The analyzed grains, together with tens of thousands of other plant remains, were retrieved during a systematic archaeological excavation headed by Uri Davidovich, from the Institute of Archaeology, The Hebrew University of Jerusalem, and Nimrod Marom, from Zinman Institute of Archaeology, University of Haifa, Israel. The archaeobotanical analysis was led by Ehud Weiss, of Bar-Ilan University. The cave is very difficult to access and was used only for a short time by humans, some 6,000 years ago, probably as ephemeral refuge.

Oldest plant genome reconstructed to date

Most examination of archaeobotanical findings has been limited to the comparison of ancient and present-day specimens based on their morphology. Up to now, only prehistoric corn has been genetically reconstructed. In this research, the team succeeded in sequencing the complete genome of the 6,000-year-old barley grains. The results are now published in the online version of the journal Nature Genetics.

“These archaeological remains provided a unique opportunity for us to finally sequence a Chalcolithic plant genome. The genetic material has been well-preserved for several millennia due to the extreme dryness of the region,” explains Ehud Weiss, of Bar-Ilan University. In order to determine the age of the ancient seeds, the researchers split the grains and subjected half of them to radiocarbon dating while the other half was used to extract the ancient DNA. “For us, ancient DNA works like a time capsule that allows us to travel back in history and look into the domestication of crop plants at distinct time points in the past,” explains Johannes Krause, Director of the Department of Archaeogenetics at the Max Planck Institute for the Science of Human History in Jena. The genome of Chalcolithic barley grains is the oldest plant genome to be reconstructed to date.

Domestication of barley completed very early

Wheat and barley were already grown 10,000 years ago in the Fertile Crescent, a sickle-shaped region stretching from present-day Iraq and Iran through Turkey and Syria into Lebanon, Jordan and Israel. Up to this day, the wild forms of these two crops persist in the region and are among the major model species studied at the Institute of Evolution in the University of Haifa. “It was from there that grain farming originated and later spread to Europe, Asia and North Africa,” explains Tzion Fahima, of the University of Haifa.

“Our analyses show that the seeds cultivated 6,000 years ago greatly differ genetically from the wild forms we find today in the region. However, they show considerable genetic overlap with present-day domesticated lines from the region,” explains Nils Stein, who directed the comparison of the ancient genome with modern genomes at the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, with the support of Robbie Waugh and colleagues at the James Hutton Institute, Dundee, Scotland, and Gary Muehlbauer, University of Minnesota, USA. “This demonstrates that the domestication of barley in the Fertile Crescent was already well advanced very early.”

The comparison of the ancient seeds with wild forms from the region and with so-called ‘landraces’ (i.e., local barley lines grown by farmers in the Near East) enabled to geographically suggest, according to Tzion Fahima and his colleagues at the University of Haifa and Israel’s Tel-Hai College, “the origin of the domestication of barley within the Upper Jordan Valley – a hypothesis that is also supported by two archaeological sites in the surrounding area where the hitherto earliest remains of barley cultivation have been found.

Immigrants “trust” in extant landraces

Also the genetic overlap with present-day domesticated lines from the region is revealing to the researchers. “This similarity is an amazing finding considering to what extent the climate, but also the local flora and fauna, as well as the agricultural methods, have changed over this long period of time,” says Martin Mascher, from the Leibniz Institute of Plant Genetics and Crop Plant Research, the lead author of the study. The researchers therefore assume that conquerors and immigrants coming to the region did not bring their own crop seeds from their former homelands, but continued cultivating the locally adapted extant landraces.

New insights into the origins of our crop plants

Combining archaeology, archaeobotany, genetics and computational genomics in an interdisciplinary study has produced novel insights into the origins of our crop plants. “This is just the beginning of a new and exciting line of research,” predicts Verena Schuenemann, from Tuebingen University, the second lead author of the study. “DNA-analysis of archaeological remains of prehistoric plants will provide us with novel insights into the origin, domestication and spread of crop plants.”

Source: Bar-Ilan University news release.

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Funnel for beer making from Mijiaya. Image courtesy Jiajing Wang.

Funnel for beer making from Mijiaya. Image courtesy Jiajing Wang.

 

Original Article:

popular-archaeology.com

Archaeologists discover evidence for a 5,000-year-old beer concoction and the earliest known occurrence of barley in China.

Archaeological artifacts from a site in northern China suggest a 5,000-year-old recipe for beer, according to a study*. The time of onset of beer brewing in ancient China remains unclear. Jiajing Wang and colleagues report the discovery of brewing artifacts in two pits dated to around 3400-2900 BC and unearthed at Mijiaya, an archaeological site near a tributary of the Wei River in northern China. Yellowish remnants found in wide-mouthed pots, funnels, and amphorae suggest that the vessels were used for beer brewing, filtration, and storage. Stoves found in the pits likely provided heat for mashing grains. Morphological analysis of starch grains and phytoliths found inside the artifacts revealed broomcorn millets, barley, Job’s tears, and tubers; some starch grains bore marks reminiscent of malting and mashing. The presence of oxalate, a byproduct of beer brewing that was identified using ion chromatography, in some of the artifacts further supported their use as brewing vessels. Together, the lines of evidence suggest that the Yangshao people may have concocted a 5,000-year-old beer recipe that ushered the cultural practice of beer brewing into ancient China. According to the authors, the identification of barley residues in the Mijiaya artifacts represents the earliest known occurrence of barley in China, pushing back the crop’s advent in the country by approximately 1,000 years and suggesting that the crop may have been used as a beer-making ingredient long before it became an agricultural staple.

 

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Barley Field

Barley Field

 

Ancient mortars holes Native American

Ancient mortars holes Native American THESE MORTARS could well be similar to the ones discussed in the following article.

 

Original article:

Eurkalert.org

PUBLIC RELEASE: 26-AUG-2015

BAR-ILAN UNIVERSITY

 

Team including researchers from Bar-Ilan University and Harvard University unravel the mystery of 12,500-year-old rock-cut mortars found throughout Southwestern Asia.

 

Using 12,500-year-old conical mortars carved into bedrock, they reconstructed how their ancient ancestors processed wild barley to produce groat meals, as well as a delicacy that might be termed “proto-pita” – small loaves of coal-baked, unleavened bread. In so doing, they re-enacted a critical moment in the rise of civilization: the emergence of wild-grain-based nutrition, some 2,000 to 3,000 years before our hunter-gatherer forebears would establish the sedentary farming communities which were the hallmark of the “Neolithic Revolution”.

The research team, consisting of independent researchers as well as faculty members from Bar-Ilan and Harvard Universities, conducted their study in the Late Natufian site of Huzuq Musa, located in Israel’s Jordan Valley. Their findings were published in the journal Plos One on July 31, 2015.

When Did Agriculture Begin?

Most investigators agree that cereal domestication was achieved about 10,500 years ago. The current work demonstrates how groat meals and fine flour were produced from wild barley, two to three millennia before the appearance of domesticated grains.

According to Prof. Mordechai Kislev, an expert in archaeo-botony who is a member of Bar-Ilan University’s Mina and Everard Goodman Faculty of Life Sciences, the team’s field work resolved a long-standing mystery about thousands of cone-shaped hollows carved into the bedrock throughout the Southern Levant.

“The conical, human-made hollows, found all over Southeast Asia, were noticed by archaeologists decades ago, but there was no agreement about their function,” Prof. Kislev says. “Assuming they were mortars used for the processing of plant food, my colleagues – under the direction of archaeologist Dr. David Eitam – decided to use these ancient stone tools, along with period-appropriate items such wooden pestles, sticks and sieves, to reconstruct how the work was done.”

Along with Eitam and Kislev, additional members of the team were physicist Adiel Karty and Prof. Ofer Bar-Yosef, a member of Harvard University’s Department of Anthropology.

From Field to Food Ingredient

The experiment began by collecting spikelets – the coated grains of a cereal ear – from wild barley, the most common wild cereal in the Levant both in prehistory and today. After ripening on the ground to prevent them from scattering in the wind, the grains were then separated from the stalks, first by beating against the threshing floor with a curved stick, and subsequently, by sifting them through a large-holed sieve.

“At this point, the conical mortars were used to complete the transformation of wild grain into groats and flour that could be used for food,” says team member Adiel Karty, explaining that the different-sized mortars served specific agricultural purposes. “Filled with a measure of the raw grain and beaten with a wooden pestle, the wider cones were used for hummeling – removal of the bristle that extends from the edge of the seed,” he explains. “The narrower cones came into play during the next stage, when the same wooden pestle was used to remove the grain husk; the Natufians invented a peeling-milling machine long before the invention of machinery!”

After de-husking, the grain was scooped out of the conical mortar by hand then placed into a small cup cut in the adjacent bedrock. From there, it was transferred for filtering in a small-gauge sieve.

“We found that de-husking – and the later milling into flour – was significantly aided by the presence of these cup-like depressions, which could be used to deposit material produced in the mortar by repeated hand-scooping from its bottom,” says Dr. Eitam. “This was a kind of labor-saving device, making it easier to transfer the grain and waste material to a sieve or other vessel.”

Evolution and Contribution

Prof. Ofer Bar-Yosef, an emeritus faculty member at Harvard who is a world-renowned expert on the origin of modern humans and early farming societies in the ancient Near East, says that the current study complements nearly 80 years of investigations suggesting that the Natufians – although subsisting as a hunter-gatherer society – used sickles to harvest wild, almost-ripe cereals, and were capable of producing large quantities of groat meals from roasted, “half green” barley grain. Moreover, the technological advance from wide-to narrow-cone mortars represented a major dietary change, because de-husked flour made it possible to produce the fine flour needed for what has become the Western world’s most widespread staple food: bread.

“With the development of a new agro-technological system, including threshing floors, peeling utensils and milling devices, the Natufians bequeathed to their Neolithic successors a technical advancement that contributed to the establishment of agricultural societies,” Prof. Bar-Yosef says.

Bon Appetite! Barley Bread for (Nearly) All

Prof. Kislev points out that the barley-processing “facilities” found at the site indicate that stone-utensil-produced flour could have been a significant part of the local Natufian diet.

“Huzuq Musa is estimated to have had a population of about a hundred people,” he says. “If we assume that the historical 35 liters of grain given to a Roman worker during the winter corresponds to a reasonable level of nutrition, the four large threshing floors discovered near the site – and its accompanying tools – could have produced a sufficient quantity of processed barley for its estimated inhabitants.”

“Producing food from wild barley grain was not easy, but the biggest challenge may have been the challenge of not harvesting all the wild grain in the field, and ensuring that there would be something left to eat the following year,” he says. “This Natufian advance was a bridge to the Neolithic revolution, when sedentary farmers developed the discipline needed to plan for the successful planting – and reaping – of domesticated grains.”

According to Dr. Eitam, the majority of scholars agree that Natufian culture was characterized by the first communities that inhabited permanent settlements. “Our discovery of this sophisticated agro-technological system indicates that Natufian society made the shift from hunting-gathering to an agriculture-based economy, which was possibly extant 3,000 years before the domestication of cereal,” he says.

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Scientists have scrutinized the contents of four bottles of beer found in a Baltic Sea shipwreck from the 1840s, an amber ale that perhaps was brewed in Belgium and was on its way to ports in Russia or Scandinavia.

The new analysis found that bacteria inside the beer bottles survived 170 years until it was discovered by divers in 2010, according to Brian Gibson, senior scientist at the VTT Technical Research Centre in Espoo, Finland.

“These bacteria were still alive,” Gibson said. The analysis “gave us some insight into the way that beers were brewed. We have a reasonably good idea about what kind of hops were used, different ones than today. These hops would have been harsher, these days they are quite mild. The one surprising thing is the beers were quite mild. The original alcohol level was 4.5 percent, nothing extreme.”

Gibson and colleagues at the University of Munich published their chemical and microbiological analysis recently in the Journal of Agriculture and Food Chemistry.

While some breweries have recreated ancient beer recipes from colonial, medieval or even Egyptian eras, Gibson believes this is the oldest intact bottle of beer. Over time, seawater seeped through the cork and made the contents about 30 percent saltwater. As a result, the big tasting by beer experts in Finland was a bit of a bust.

“The beer was quite degraded, it had a sell by date and it appeared to be well past that,” he said. “For the analysis, it was difficult to pick out the original flavors. We invited some of the most experienced beer tasters in Finland. The flavors were from bacterial contamination and not the original flavors of the beer.”

The scientists turned to chemical analysis of the remaining sugars and

“We looked at esters, which give beer a fruity or flowery taste. Most of the compounds that we would expect were there. In terms of the fruitiness, probably similar to modern beers. High level of 2-phenyl ethanol which gives a rose or floral aroma.”

Compared to modern craft brews, Gibson said it was like an amber or lambic ale, modern styles that are brewed with wild hops, floral and have sour notes.

Sam Calagione, founder and president of Dogfish Head brewery in Milton, Del., had been brewing historic beers since 1998, using recipes from archaeological digs that are passed on by scientists.

Dogfish’s “Midas Touch,” which is brewed from evidence found in a 2,700-year-old tomb in Turkey, is comprised of barley, saffron and white muscat grapes.

“The whole idea of looking backward for creative inspiration and culinary adventure is really catching on,” Calagione said. “All (the scientists) can give us is a laundry list of ingredients. It is up to us to come up with a creative recipe. What the alcohol content is, whether it’s filtered or carbonated. We have a lot of creative input in bringing these creative beers back to life.”

Stallhagen Brewery in the Aaland Islands of Finland recently re-created the Baltic Sea brew, called “1843.”

By Eric Niiler

Original article:

News.discovery.com

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Plant particles found during the excavation of this Neolithic cemetery in Nubia (Sudan) turned out to be traces of domestic cereals when analysed in a lab. copyright: D. Usai/ S. Salvatori

A research team successfully identified ancient barley and wheat residues in grave goods and on teeth from two Neolithic cemeteries in Central Sudan and Nubia, showing that humans in Africa were already exploited domestic cereals 7,000 years ago and thus five hundred years earlier than previously known.

The results of the analyses were recently published in the open access journal PLOS ONE.

Barley and wheat crops

Dr. Welmoed Out from Kiel University said, “With our results we can verify that people along the Nile did not only exploit gathered wild plants and animals but had crops of barley and wheat.”

These types of crops were first cultivated in the Middle East about 10,500 years ago and spread out from there to Central and South Asia as well as to Europe and North Africa – the latter faster than expected.

The diversity of the diet was much greater than previously assumed,” states Out and adds: “Moreover, the fact that grains were placed in the graves of the deceased implies that they had a special, symbolic meaning.”

The research team, coordinated by Welmoed Out and the environmental archaeologist Marco Madella from Barcelona, implemented, among other things, a special high-quality light microscope as well as radiocarbon analyses for age determination. Hereby, they were supported by the fact that mineral plant particles, so-called phytoliths, survive very long, even when other plant remains are no longer discernible. In addition, the millennia-old teeth, in particular adherent calculus, provide evidence on the diet of these prehistoric humans due to the starch granules and phytoliths contained therein.



One of the graves at the Neolithic cemetery in Nubia (Sudan), containing a skeleton and plant material deposited behind the skull (white area at the left picture margin). Copyright: D. Usai/ S. Salvatori

Original article:

Past horizons



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