Saturday, March 29, 2014
Friday, March 28, 2014
SERRA DA CAPIVARA NATIONAL PARK, Brazil — Niede Guidon still remembers her astonishment when she glimpsed the paintings.
Preserved amid the bromeliad-encrusted plateaus that tower over the thorn forests of northeast Brazil, the ancient rock art depicts fierce battles among tribesmen, orgiastic scenes of prehistoric revelry and hunters pursuing their game, spears in hand.
“These were stunning compositions, people and animals together, not just figures alone,” said Dr. Guidon, 81, remembering what first lured her and other archaeologists in the 1970s to this remote site where jaguars still prowl.
Hidden in the rock shelters where prehistoric humans once lived, the paintings number in the thousands. Some are thought to be more than 9,000 years old and perhaps even far more ancient. Painted in red ocher, they rank among the most revealing testaments anywhere in the Americas to what life was like millenniums before the European conquest began a mere five centuries ago.
But it is what excavators found when they started digging in the shadows of the rock art that is contributing to a pivotal re-evaluation of human history in the hemisphere.
Humans’ First Appearance in the Americas
In Piauí, Brazil, archaeologists say stone tools prove that humans reached what is now Brazil as early as 22,000 years ago, upending a belief that people first arrived about 13,000 years ago.
Researchers here say they have unearthed stone tools proving that humans reached what is now northeast Brazil as early as 22,000 years ago. Their discovery adds to the growing body of research upending a prevailing belief of 20th-century archaeology in the United States known as the Clovis model, which holds that people first arrived in the Americas from Asia about 13,000 years ago.
“If they’re right, and there’s a great possibility that they are, that will change everything we know about the settlement of the Americas,” said Walter Neves, an evolutionary anthropologist at the University of São Paulo whose own analysis of an 11,000-year-old skull in Brazil implies that some ancient Americans resembled aboriginal Australians more than they did Asians.
Up and down the Americas, scholars say that the peopling of lands empty of humankind may have been far more complex than long believed. The radiocarbon dating of spear points found in the 1920s near Clovis, N.M., placed the arrival of big-game hunters across the Bering Strait about 13,000 years ago, long forming the basis of when humans were believed to have arrived in the Americas.
More recently, numerous findings have challenged that narrative. In Texas,archaeologists said in 2011 that they had found projectile points showing that hunter-gatherers had reached another site, known as Buttermilk Creek, as early as 15,500 years ago. Similarly, analysis of human DNA found at an Oregon cave determined that humans were there 14,000 years ago.
But it is in South America, thousands of miles from the New Mexico site where the Clovis spear points were discovered, where archaeologists are putting forward some of the most profound challenges to the Clovis-first theory.
Paleontologists in Uruguay published findings in November suggesting that humans hunted giant sloths there about 30,000 years ago. All the way in southern Chile, Tom D. Dillehay, an anthropologist at Vanderbilt University, has shown that humans lived at a coastal site called Monte Verde as early as 14,800 years ago.
Reassessing Human History in the Americas
Researchers at Serra da Capivara National Park unearthed stone tools last year that they say prove that humans reached what is now northeast Brazil as early as 22,000 years ago. Their discovery adds to the growing body of research upending a prevailing belief of 20th-century archaeology in the United States known as the Clovis model, which holds that people first arrived in the Americas from Asia about 13,000 years ago.
And here in Brazil’s caatinga, a semi-arid region of mesas and canyons, European and Brazilian archaeologists building on decades of earlier excavations said last year that they had found artifacts at a rock shelter showing that humans had arrived in South America almost 10,000 years before Clovis hunters began appearing in North America.
“The Clovis paradigm is finally buried,” said Eric Boëda, the French archaeologist leading the excavations here.
Exposing the tension over competing claims about where and when humans first arrived in the Americas, some scholars in the dwindling Clovis-first camp in the United States quickly rejected the findings.
Gary Haynes, an archaeologist at the University of Nevada, Reno, argued that the stones found here were not tools made by humans, but instead could have become chipped and broken naturally, by rockfall. Stuart Fiedel, an archaeologist with the Louis Berger Group, an environmental consulting company, said that monkeys might have made the tools instead of humans.
“Monkeys, including large extinct forms, have been in South America for 35 million years,” Dr. Fiedel said. He added that the Clovis model was recently bolstered by new DNA analysis ancestrally connecting indigenous peoples in Central and South America to a boy from the Clovis culture whose 12,700-year-old remains were found in 1968 at a site in Montana.
Such dismissive positions have invited equally sharp responses from scholars like Dr. Dillehay, the American archaeologist who discovered Monte Verde. “Fiedel does not know what he is talking about,” he said, explaining that similarities existed between the stone tools found here and at the site across South America in Chile. “To say monkeys produced the tools is stupid.”
Having their findings disputed is nothing new for the archaeologists working at Serra da Capivara. Dr. Guidon, the Brazilian archaeologist who pioneered the excavations, asserted more than two decades ago that her team had found evidence in the form of charcoal from hearth fires that humans had lived here about 48,000 years ago.
While scholars in the United States generally viewed Dr. Guidon’s work with skepticism, she pressed on, obtaining the permission of Brazilian authorities to preserve the archaeological sites near the town of São Raimundo Nonato in a national park that now gets thousands of visitors a year despite its remote location in Piauí, one of Brazil’s poorest states.
Dr. Guidon remains defiant about her findings. At her home on the grounds of a museum she founded to focus on the discoveries in Serra da Capivara, she said she believed that humans had reached these plateaus even earlier, around 100,000 years ago, and might have come not overland from Asia but by boat from Africa.
Professor Boëda, who succeeded Dr. Guidon in leading the excavations, said that such early dates may have been possible but that more research was needed. His team is using thermoluminescence, a technique that measures the exposure of sediments to sunlight, to determine their age.
At the same time, discoveries elsewhere in Brazil are adding to the mystery of how the Americas were settled.
In what may be another blow to the Clovis model of humans’ coming from northeast Asia, molecular geneticists showed last year that the Botocudo indigenous people living in southeastern Brazil in the late 1800s shared gene sequences commonly found among Pacific Islanders from Polynesia.
How could Polynesians have made it to Brazil? Or aboriginal Australians? Or, if the archaeologists here are correct, how could a population arrive in this hinterland long before Clovis hunters began appearing in the Americas? The array of new discoveries has scholars on a quest for answers.
Reflecting how researchers are increasingly accepting older dates of human migration to the Americas, Michael R. Waters, a geoarchaeologist at Texas A&M University’s Center for the Study of the First Americans, said that a “single migration” into the Americas about 15,000 years ago may have given rise to the Clovis people. But he added that if the results obtained here in Serra da Capivara are accurate, they will raise even more questions about how the Americas were settled.
“If so, then whoever lived there never passed on their genetic material to living populations,” said Dr. Waters, explaining how the genetic history of indigenous peoples links them to the Clovis child found in Montana. “We must think long and hard about these early sites and how they fit into the picture of the peopling of the Americas.”
Source: The New York Times
Thursday, March 27, 2014
The diet and journeys taken by those who lived in the Sahara Desert thousands of years ago are being analysed through their teeth and bones.
Wednesday, March 26, 2014
An ancient stone carving on the walls of an Egyptian temple depicts the Roman emperor Claudius dressed as an Egyptian pharaoh, wearing an elaborate crown, a team of researchers has discovered.
In the carving, Emperor Claudius, who reigned from A.D. 41 to 54, is shown erecting a giant pole with a lunar crescent at the top. Eight men, each wearing two feathers, are shown climbing the supporting poles, with their legs dangling in midair.
Egyptian hieroglyphs in the carving call Claudius the "Son of Ra, Lord of the Crowns," and say he is "King of Upper and Lower Egypt, Lord of the Two Lands." The hieroglyphs say he is raising the pole of the tent (or cult chapel) of Min (an ancient Egyptian god of fertility and power) and notes a date indicating a ritual like this took place around the summertime researchers say. It would have taken place even though Claudius never visited Egypt. A cult chapel is a place of worship and a tent could also be used for this purpose. [See Photos of the Egyptian Carving and Emperor]
The elaborate crown on Claudius consists of three rushes (plants) set on ram horns with three falcons sitting on top. Three solar discs representing the sun (one for each plant) are shown in front of the rushes. Egyptian rulers are shown wearing crowns like this relatively late in ancient Egyptian history, mainly after 332 B.C., and they were worn only in Egypt. The Roman Empire took over Egypt in 30 B.C., and while the Roman emperors were not Egyptian, they were still depicted as pharaohs Egyptologists have noted.
In the recently discovered carving, the god Min is shown wearing his own crown and has an erect penis, because Min was a god of fertility, the researchers said. The hieroglyphs describe Min as "the one who brings into control the warhorses, whose fear is in the Two Lands." Min tells Claudius, "I give you the (southern) foreign lands," which researchers say could be a reference to the deserts surrounding the Nile River, where minerals could be quarried.
The scene was discovered on the western exterior wall of the Temple of Isis at Shanhur, located on the east bank of the Nile River about 12 miles (20 kilometers) north of Luxor. It is an Egyptian temple built and decorated during the Roman occupation under Augustus (who reigned from about 30 B.C. to A.D. 14) through to Trajan (who reigned from A.D. 98 to 117). The pole-raising scene was first found during the 2000-2001 excavation season and was recorded in full during the 2010 epigraphic (recording) season. The temple originally had 36 scenes on each of its eastern and western exterior walls, and this new scene, protected for millennia by a layer of dirt, is one of the best preserved.
The study was published recently in the journal Zeitschrift für ägyptische Sprache und Altertumskunde by Martina Minas-Nerpel, a Reader (the American equivalent of an associate professor) at Swansea University in the United Kingdom, and Marleen De Meyer, a postdoctoral researcher at KU Leuven University in Belgium. Careful line drawings of the scene were done by Troy Sagrillo, a senior lecturer at Swansea University.
Although Cleopatrais often called the "last pharaoh of Egypt," the Egyptian priests depicted the Roman emperors as pharaohs up until the fourth century A.D. The Roman emperors allowed, or even encouraged, these depictions in Egyptian temples in order to keep Egypt — which was an important Roman province — stable. [Cleopatra & Olympias: Top 12 Warrior Moms in History]
"Although we know that Claudius, as most Roman emperors, never visited Egypt, his rule over the land at the Nile and the desert regions was legitimized through cultic means," Minas-Nerpel and De Meyer wrote in the journal article. "By decorating the exterior temple wall with this ritual, Claudius theoretically received Min's characteristics and thus his ability to rule over Egypt."
The researchers noted that similar scenes showing a pole being raised for the god Min date as far back as 4,300 years ago, during the age when pyramids were being built in Egypt. This tradition of creating pole-raising scenes was continued into the period of Roman rule.
In addition, the date on the carving indicates that a ritual like this took place in real life, the researchers said, adding that people may have climbed the central pole of the chapel of Min. In fact, a priest may have stood in for the absent Claudius, and a statue could have been used to represent Min, Minas-Nerpel said.
"What we see depicted on the temple scene is the ideal scenario," Minas-Nerpel told Live Science. She added that, even before the Romans took over Egypt in 30 B.C., Egypt's pharaohs were unable to take part in each temple ceremony in person, and stand-ins would have been necessary.
Another ritual offering at the Shanhur temple depicted at the axially corresponding scene on the eastern exterior wall shows Claudius giving an offering of lettuce to Min, which symbolizes the continuedfertility of Egypt. It is located on the east wall and did not have to be excavated. In this scene, the Egyptian god Horus (shown as a child) is depicted between the two.
"[Take for] you the lettuce in order to unite it with your body (or phallus)," Claudius says to Min in hieroglyphs shown on the depiction. At one point, Claudius says, "One is in fear when seeing your face."
The two scenes highlight fertility and victorious power, both of which were important for legitimizing the rule of an absent Roman emperor who wanted to control Egypt, Minas-Nerpel and De Meyer wrote.
The Shanhur project and team
In 2009, Minas-Nerpel (principal investigator) and Harco Willems, a professor of Egyptology at the KU Leuven in Belgium, were jointly awarded the research grant by the Gerda Henkel-Foundation of Düsseldorf, Germany, to continue research at the temple of Isis at Shanhur in Upper Egypt. The project was also sponsored by the Engineering and Physical Science Research Council in the United Kingdom. The international team also included De Meyer, Peter Dils (of the Universität Leipzig in Germany), René Preys (of the Facultés Universitaires Notre-Dame de la Paix in Namur and KU Leuven), and Sagrillo. In Egypt, the mission was supported by the Supreme Council of Antiquities, theDeutsches Archäologisches Institut, Cairo (DAI) and the Nederlands-Vlaams Instituut in Cairo.
An article on Shanhur temple by De Meyer and Minas-Nerpel can be seen on the UCLA Encyclopedia of Egyptology athttp://escholarship.org/uc/item/5hc3t8dh.
Tuesday, March 25, 2014
Glass is, in the modern world, nearly ubiquitous. It’s everywhere. Glass has been one of the most useful inventions ever made, though invention isn’t really the right word, it was more of a discovery. The art of making glass is relatively simple, though it certainly isn’t easy. What actually happens to the constituent materials is anything but simple, however.
You’re probably familiar with the term vitrification. If not, here’s a crash course.
Glass is, by definition, an amorphous solid material that exhibits a glass-transition. A less-than-helpful definition to be sure, but essentially that means that it’s a non-crystalline material that, at different temperatures, transitions between a hard and brittle substance to a semi-liquid molten substance (and vice versa). This is similar to a phase-transition, but is a distinctly separate process.
There are several types of glass, based on the above definition, but what we commonly know as glass is generally a mixture of silicon dioxide, sodium oxide, and lime (as well as various other additives in small amounts) that, through a process of heating and rapid cooling is changed from its constituent form, to a molten form, and then to an amorphous solid form. It’s that last step, super-cooling a viscous liquid into a solid form, that’s called vitrification. A more generally held definition is the melting of sand (or the silica/quartz in sand) and then cooling it into a solid material, the result often being visually similar to glass.
As a term, vitrification is widely misunderstood, and is commonly used to describe the process of making glass. It isn’t limited to the common idea of glass though, so that isn’t really correct. The term vitrified sand refers to a group of natural and man-made processes that result in melted sand. It’s caused by lightning strikes (fulgurite), super-heated meteorites (tekkite), nuclear detonations (trinitite), and in the process of making glass (frit). There’s also volcanic glass, which isn’t really vitrified sand, because often it’s isn’t made up by quartz or silica, but more stratified molten material
Any way you slice it though, glass making is pretty neat. Even though, as mentioned, glass making isn’t exactly easy, the simple process is even undertaken by Mother Nature herself, and the results are often spectacular. Fulgurite in particular, sometimes called petrified lightning, which is most often found as tubes of fused quartz at locations of lightning strikes, produces some stunningly gorgeous formations. There are people who collect fulgurite and there’s even jewellery made out of it.
The Fortean Community is not unfamiliar with vitrified sand, as there are many examples of what appear to be trinitite in antiquity, such as that at the vitrified forts in Ireland and Scotland. Some conspiracy theorists contend that those examples of vitrified sand are evidence of atomic blasts and advanced weaponry in pre-history, though analysis of these sites suggests that they are actually examples of fulgurite and/or tekkite, rather than trinitite.
There are glass related mysteries that don’t rely on conspiracy theory though.
Glass has some interesting properties, not the least of which is its ability to hold refreshingly cold liquids at the ready for consumption. It has the ability to both reflect and refract light, which is a pretty handy thing, when it comes down to it. That inherent property is what makes it so useful to us, beyond kitchenware.
When Sir Isaac Newton discovered that a prism has the ability to separate the spectrum of visible light, and subsequently invented the spectrometer and later built the first practical reflecting telescope, he found a use for glass that ultimately revolutionised science. And while he is credited with formulating the Theory of Colour, it seems he wasn’t the first to figure out that glass has the ability to produce some surprising colour effects.
Made, it’s believed, in the 4th century AD by Roman artisans, there is a cup that seems to defy logic with its ability to change colour based on light that’s shone through it. The only surviving example of a Roman cage cup, the Lycurgus Cup – named so because it bears a relief image of the legendary lawmaker Lycurgus of Sparta – is the earliest known piece of manufactured dichroic glass.
What’s dichroic glass? Funny you should ask.
It actually refers to two specific types of glass. The first being the modern manufactured glass used in thin-film optics (such as LCD screens) and stained glass, where ultra-thin layers of various metals are used to alter the refraction angle of light as it passes through the glass, resulting in different colours when viewed from different angles. The second is the kind used in the Lycurgus cup, wherein nanoparticles of silver and gold are included in the vitrification of the silica or quarts, which results in the glass actually changing colour based on the position of light sources and the observer.
It makes for a beautiful effect, as you can see from the pictures, but there’s a problem.
As mentioned, this is an example of a Roman cage cup or dietretum, which means that the glass was painstakingly ground and cut away leaving a decorative “cage” at the original surface-level. We know that they were a common possession for elite Romans, but due to the delicate nature of the cup, only this one example has survived the ages. There are a few other examples of Roman dichroic glass, all of which are small shards, and through analysis, it seems the Romans were fairly adept at manipulating the content of their frit, though, in the case of dichroic glass, we’re talking about microscopic nanoparticles of the metal here, achieving a very specific colloidal mixture in the molten glass in order to create the desired effect.
How did they do that? Is this evidence that Roman scientific knowledge was more advanced than we previously thought, in this case far more advanced?
Modern scholars are unable to explain exactly how they achieved this feat, which even today is difficult. It’s thought, by the mainstream scientific establishment, that they stumbled onto it accidentally, which to some is a painfully inadequate hypothesis. There are those who declare that the Roman Empire, and perhaps even cultures that predate them, had or were familiar with nanotechnology. This isn’t a new claim of antiquity, but it is one of the only cases of speculation in that regard that isn’t easily dismissed.
Is this yet another example of what a growing number of people claim is evidence for a lost global knowledge fund? The Lycurgus cup and the other examples of Roman-era dichroic glass were made deliberately. The craftsmen responsible knew precisely what they were doing…the question is, how did they know it?
Source: Mysterious Universe
Wrapped in bandages and caricatured as figures of terror in Hollywood movies, Egypt’s mummies have long captivated and bewildered scientists and children alike.
Now a new exhibition at the British Museum will disclose the human side of the mummies of the Nile.
Eight have been – scientifically speaking – stripped bare revealing secrets taken to the grave thousands of years ago.
Subjecting the corpses to the most advanced scientific techniques, including sending the mummies to hospitals around London for CAT scans – the museum’s Egyptologists have been able to build up the most detailed picture yet of what lies beneath the sarcophagi and bandage-wrapped bodies.
The exhibition called Ancient Lives: New Discoveries, which opens in May, will show mummies in a new – and often ordinary – light.
The new analysis has unearthed evidence that, just like modern man, ancient Egyptians suffered from high cholesterol and agonising toothache. They even had tattoos.
CT scan 3D visualisation of the mummified remains of a Sudanese woman (Trustees of the British Museum)
The exhibition is likely to be one of the most successful ever staged by the British Museum and follows in a fine tradition of blockbuster displays based on archaeological finds from ancient Egypt. The Treasures of Tutankhamun, staged at the museum in 1972, attracted more than 1.6 million visitors.
The new exhibition looks at those living along the ancient Nile from royalty to more ordinary inhabitants.
Mummification, the curators are keen to point out, was not the sole preserve (pardon the pun) of pharaohs. Curators have deliberately chosen mummies from different eras and different backgrounds to cast them in a new light.
The oldest of the mummies to undergo scientific testing is more than 5,500 years old and dates back to 3,500 BC. The most recent example is a female aged between 20 and 35, who lived about 1,300 years ago.
CAT scanning of one the mummies (JULIAN SIMMONDS)
The mummies range in ages from two years at the moment of death to 50. Some were discovered by explorers more than 100 years ago while others were found as recently as 2005 on the banks of the Nile in what is now Sudan.
Over the course of several months, the mummies were taken at night to hospitals and subjected to scans normally reserved for living patients.
CAT scans – or computed tomography to give it its technical term – generate three-dimensional images of patients’ organs, bones and tissue using X-ray technology. Some of the mummies were so well preserved that the scans revealed parts of the brain and other vital organs still intact.
The CAT scan images of the mummies were then combined with other forensic detective work, such as infra-red “reflectography” and carbon dating, to build up a picture of ancient lives.
“What we are doing in the exhibition is investigating the lives of eight people from the past,” said John Taylor, head curator in the Ancient Egypt and Sudan department at the museum.
“We want to promote the idea these are not objects but real human beings. We want to capture the humanity of these people.”
Dr Taylor said: “We took the mummies to hospitals mainly around London. We used the facilities after hours. We used a sophisticated dual energy scanner that gave us X-rays of different layers.
“We captured some amazing images and discovered a lot about these mummies even though some of them have been here at the museum for 100 years or more. Most of the remains have never had the bandages taken off.”
CAT scans of the pelvic area enabled the team to age the corpses, based on wear and tear of the bones. The scans also showed how the ancient inhabitants of the Nile suffered from heart disease and toothache.
Displays at the British Museum (JULIAN SIMMONDS)
Two of the eight mummies appeared to have suffered from heart problems. The two mummies were found to have suffered from plaque in their legs. Plaque is made up of cholesterol, calcium and tissue and as it builds up arteries narrow.
Daniel Antoine, the museum’s curator of physical anthropology and curator of the coming exhibition, said: “The scans showed two of them with plaque in the leg.
“That is an indication of cardiovascular disease that can lead to a heart attack or stroke. This might have been caused by lifestyle which means a diet rich in fat or it might be genetic. The other major find was that the majority of adults had terrible dental health. They had huge abscesses.
“In some cases the mummies have such multiple abscesses that it might have contributed to the death. You can get such severe inflammation of the throat that can lead to asphyxiation.”
The ancient Egyptians ate a varied diet that included fish, a little meat, beer, bread and sugar-rich fruits such as dates.
The scientists at the British Museum even studied bread found with the remains of the mummies to see if it had a high content of abrasive sand that might have contributed to tooth decay – it didn’t.
One of the mummies, whose remains were found just seven years ago, was so well preserved that archaeologists could almost make out the tattoo on her skin on the inner thigh of her right leg with the naked eye. Infra-red technology helped define it more clearly.
The woman, aged between 20 and 35, had been buried wrapped in a linen and woollen cloth and her remains had mummified in the dry heat. The tattoo has been deciphered by curators and spells out in ancient Greek – M-I-X-A-H-A, or Michael.
The owner of the tattoo was a woman who died in about AD 700 and lived in a Christian community on the banks of the Nile.
A photograph, left, and an infra-red reflectography of the tattoo found on the mummified remains of a Sudanese woman (Trustees of the British Museum)
The tattoo represents the symbol of the Archangel Michael, who features in both the Old and New Testaments. The symbol has previously been found in ancient churches and on stone tablets, but never before in the form of a tattoo.
“You can see her tattoo really clearly using infra red reflectography,” said Dr Antoine, “The tattoo on her right inner thigh represents a monogram that spells Michael in ancient Greek.
“She is the first evidence of a tattoo from this period. This is a very rare find.”
The woman was about 5ft 2in tall and was found in 2005 on an archaeological dig in a cemetery in Sudan. Other ancient Egyptians who were mummified had their organs removed before being preserved.
“The scan of the Sudanese mummy showed her internal organs are remarkably well preserved,” said Dr Antoine. “We can only speculate why she had a tattoo. Perhaps for protection.”
The Sudanese mummy will go on public display for the first time in May. Each day thousands of people will see her tattoo.
It is not clear who did the tattoo in ancient Sudan, and whether it was visible to other natives.
High up on her inner thigh, it may or may not have been out of view. And for all its scientific expertise, the British Museum admits to being unclear as to what exactly was the fashionable length of skirt worn by an ordinary Nile dwelling female in AD 700.
Source: The Telegraph