Sunday, December 23, 2007

Ancient Egyptian Glassmaking Recreated


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ScienceDaily (Dec. 21, 2007) — A team led by a Cardiff University archaeologist has reconstructed a 3,000-year-old glass furnace, showing that Ancient Egyptian glassmaking methods were much more advanced than previously thought.
Dr Paul Nicholson, of the University's School of History and Archaeology, is leader of an Egypt Exploration Society team working on the earliest fully excavated glassmaking site in the world. The site, at Amarna, on the banks of the Nile, dates back to the reign of Akhanaten (1352 - 1336 B.C.), just a few years before the rule of Tutankhamun.
It was previously thought that the Ancient Egyptians may have imported their glass from the Near East at around this time. However, the excavation team believes the evidence from Amarna shows they were making it themselves, possibly in a single stage operation. Dr Nicholson and his colleague Dr Caroline Jackson of Sheffield University demonstrated this was possible, using local sand to produce a glass ingot from their own experimental reconstruction of a furnace near the site.
The team have also discovered that the glassworks was part of an industrial complex which involved a number of other high temperature manufacturing processes. The site also contained a potter's workshop and facilities for making blue pigment and faience - a material used in amulets and architectural inlays. The site was near one of the main temples at Amarna and may have been used to produce materials in state buildings.
Dr Nicholson, who has been working at Amarna since 1983, said: "It has been argued that the Egyptians imported their glass and worked it into the artefacts that have been discovered from this time. I believe there is now enough evidence to show that skilled craftsmen could make their own glass and were probably involved in a range of other manufacturing industries as well."
Dr Nicholson has now written a book detailing the discoveries made at Amarna. Entitled Brilliant Things for Akhenaten, it is published by the Egypt Exploration Society (London) and available through Oxbow Books in the UK and The David Brown Book Company in the USA.
Adapted from materials provided by Cardiff University.

Fausto Intilla

Sunday, December 16, 2007

Andean Highlands In Chile Yield Ancient South American Armored Mammal Fossil


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ScienceDaily (Dec. 14, 2007) — A paleontological dig in Chile at an altitude of more than 14,000 feet in the Andes has yielded fossils of an 18-million-year-old armored mammal. It appears to be one of the most primitive members of a family of extinct mammals known as "glyptodonts," a group closely related to the modern-day armadillo.
Darin Croft from Case Western Reserve University, John Flynn from the American Museum of Natural History and Andre R. Wyss from the University of California Santa Barbara report the discovery and describe the mammal in the Journal of Vertebrate Paleontology.
Researchers have named the animal, Parapropalaehoplophorus septentrionalis. They derived the first part of the name from the new mammal's resemblance to a slightly younger animal from Argentina (Propalaehoplophorus). Septentrionalis means northern in Latin.
The newly discovered animal lived in the early Miocene epoch about 18 million years ago and its family went extinct about the time humans arrived in the New World.
P. septentrionalis is a member of the glyptodonts, a large group of extinct animals that lived almost exclusively in South America. (A few species reached North America several million years ago when the two continents were reconnected by the Panamanian land bridge.) They are recognized for their thick shells of hardened and immovable bony plates and their large, grooved teeth. But unlike their modern day armadillo relatives (who have thinner shells with movable plates and smaller, simple teeth), these animals could grow to the size of a small car and weigh as much at two tons.
According to Croft, the new species was relatively small for a glyptodont and is the first one found in Chile. "It would have looked like a cross between a tortoise and an armadillo, but of course is much more closely related to armadillos," he said. He described P. septentrionalis as roughly the size of an African spurred tortoise, which is less than three feet long and weighs about 200 pounds.
The glyptodont was reconstructed from fossils of the jaw, shell, leg and backbone. These were compared with other known glyptodonts and with close glyptodont relatives. "These different skeletal parts all gave the same answer -- this was a new species of glyptodont that had a greater number of primitive features than any other species," said Croft.
"When we collected the fossil, we had no idea that it would turn out to be a new species. We knew that it would be an important specimen, given its completeness, but it was only after cleaning it and carefully studying it that we realized how unusual it was," Croft said.
The P. septentrionalis fossil was found during a field expedition in 2004 to the Salar de Surire region. This area has yielded the Chucal fauna, the collective name given to the 18 fossil animal species from the region. This fauna includes armored mammals (armadillos and their relatives), marsupials (relatives of the opossum), rodents, frogs and many ungulates (hoofed animals).
Finding the new species was no easy task as the researchers encountered the thin air at the high altitude, scarce water and temperatures that plummeted as night fell. But these are not the conditions under which the glyptodont lived. According to Flynn from the American Museum of Natural History in New York City, "Our studies and plant work elsewhere on the Altiplano suggest that the region was at much lower elevation when these fossils lived, giving us new insights into the timing and rate of uplift of the high Andes."
Flynn added that Chucal, at more than 14,000 feet above sea level, is the highest elevation vertebrate fossil site in the Western Hemisphere. The highest site in the world is much younger and is found in the Tibetan Plateau at an altitude of more than 15,000 feet.
Like other glyptodonts, P. septentrionalis probably spent a lot of its time grazing on ground vegetation in open areas, much like cows do today. This interpretation is supported by the presence of many other open habitat mammals at Chucal and the presence of plant fossils typical of such environments.
A detailed description of the new mammal is found in the article, "A New Basal Glyptodontid and other Xenarthra of the Early Miocene Chucal Fauna, Northern Chile." The research was undertaken in collaboration with the Field Museum of Natural History in Chicago and the Museo Nacional de Historia Natural and the Consejo de Monumentos Nacionales in Santiago, Chile. Research support came from the National Geographic Society, the National Science Foundation, and FONDECYT Chile.
Adapted from materials provided by Case Western Reserve University.

Fausto Intilla

Wednesday, December 12, 2007

Massive Dinosaur Discovered In Antarctica Sheds Light On Life, Distribution Of Sauropodomorphs


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ScienceDaily (Dec. 12, 2007) — A new genus and species of dinosaur from the Early Jurassic has been discovered in Antarctica. The massive plant-eating primitive sauropodomorph is called Glacialisaurus hammeri and lived about 190 million years ago.
The recently published description of the new dinosaur is based on partial foot, leg and ankle bones found on Mt. Kirkpatrick near the Beardmore Glacier in Antarctica at an elevation of more than 13,000 feet.
"The fossils were painstakingly removed from the ice and rock using jackhammers, rock saws and chisels under extremely difficult conditions over the course of two field seasons," said Nathan Smith, a graduate student at The Field Museum. "They are important because they help to establish that primitive sauropodomorph dinosaurs were more broadly distributed than previously thought, and that they coexisted with their cousins, the true sauropods."
The findings were published online Dec. 5 in the Acta Palaeontologica Poloncica. Diego Pol, a paleontologist at the Museo Paleontológico Egidio Feruglio in Chubut, Argentina, is the other co-author of the research.
Sauropodomorph dinosaurs were the largest animals to ever walk the earth. They were long-necked herbivores and include Diplodocus and Apatosaurus. Their sister group is the theropods, which include Tyrannosaurus, Velociraptor, and modern birds.
Glacialisaurus hammeri was about 20-25 feet long and weighed about 4-6 tons . It was named after Dr. William Hammer, a professor at Augustana College who led the two field trips to Antarctica that uncovered the fossils. Glacialisaurus belongs to the sauropodomorph family Massopsondylidae, which may represent a secondary radiation of basal sauropodomorphs during the Early Jurassic.
Currently, the development and evolutionary relationships of the sauropodomorph dinosaurs are hotly debated by paleontologists. This discovery, however, helps to resolve some of this debate by establishing two things. First, it shows that sauropodomorphs were widely distributed in the Early Jurassic--not only in China, South Africa, South America and North America, but also in Antarctica.
"This was probably due to the fact that major connections between the continents still existed at that time, and because climates were more equitable across latitudes than they are today," Smith said.
Second, the discovery of Glacialisaurus hammeri shows that primitive sauropodomorphs probably coexisted with true sauropods for an extended period of time. The recent discovery of a possible sauropod at roughly the same location in Antarctica lends additional evidence to the theory that the earliest sauropods coexisted with their basal sauropodomorph cousins, including Glacialisaurus hammeri, during the Late Triassic and Early Jurassic, Smith and Pol conclude in their research findings.
Adapted from materials provided by Field Museum.

Fausto Intilla

Saturday, December 8, 2007

Most Ancient Case Of Tuberculosis Found In 500,000-year-old Human; Points To Modern Health Issues


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ScienceDaily (Dec. 8, 2007) — Although most scientists believe tuberculosis emerged only several thousand years ago, new research from The University of Texas at Austin reveals the most ancient evidence of the disease has been found in a 500,000-year-old human fossil from Turkey.
The discovery of the new specimen of the human species, Homo erectus, suggests support for the theory that dark-skinned people who migrate northward from low, tropical latitudes produce less vitamin D, which can adversely affect the immune system as well as the skeleton.
Prior to this discovery in western Turkey, which helps scientists fill a temporal and geographical gap in human evolution, the oldest evidence of tuberculosis in humans was found in mummies from Egypt and Peru that date to several thousand years ago.
Paleontologists spent decades prospecting in Turkey for remains of Homo erectus, widely believed to be the first human species to migrate out of Africa. After moving north, the species had to adapt to increasingly seasonal climates.
The researchers identified this specimen of Homo erectus as a young male based on aspects of the cranial suture closure, sinus formation and the size of the ridges of the brow. They also found a series of small lesions etched into the bone of the cranium whose shape and location are characteristic of the Leptomeningitis tuberculosa, a form of tuberculosis that attacks the meninges of the brain.
After reviewing the medical literature on the disease that has reemerged as a global killer, the researchers found that some groups of people demonstrate a higher than average rate of infection, including Gujarati Indians who live in London, and Senegalese conscripts who served with the French army during World War I.
The research team identified two shared characteristics in the communities: a path of migration from low, tropical latitudes to northern temperate regions and darker skin color.
People with dark skin produce less vitamin D because the skin pigment melanin blocks ultraviolet light. And, when they live in areas with lower ultraviolet radiation such as Europe, their immune systems can be compromised.
John Kappelman, professor of anthropology at The University of Texas at Austin, is part of an international team of researchers from the United States, Turkey and Germany who have published their findings in the Dec. 7 issue of the American Journal of Physical Anthropology.
It is likely that Homo erectus had dark skin because it evolved in the tropics, Kappelman explained. After the species moved north, it had to adapt to more seasonal climates. The researchers hypothesize the young male's body produced less vitamin D and this deficiency weakened his immune system, opening the door to tuberculosis.
"Skin color represents one of biology's most elegant adaptations," Kappelman said. "The production of vitamin D in the skin serves as one of the body's first lines of defenses against a whole host of infections and diseases. Vitamin D deficiencies are implicated in hypertension, multiple sclerosis, cardiovascular disease and cancer."
Before antibiotics were invented, doctors typically treated tuberculosis by sending patients to sanatoria where they were prescribed plenty of sunshine and fresh air.
"No one knew why sunshine was integral to the treatment, but it worked," Kappelman said. "Recent research suggests the flush of ultraviolet radiation jump-started the patients' immune systems by increasing the production of vitamin D, which helped to cure the disease."
The Leakey Foundation and the Scientific and Technical Research Council of Turkey funded the research.
Adapted from materials provided by University of Texas at Austin.

Fausto Intilla

Wednesday, December 5, 2007

Fossils Excavated From Bahamian Blue Hole May Give Clues Of Early Life


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ScienceDaily (Dec. 4, 2007) — Long before tourists arrived in the Bahamas, ancient visitors took up residence in this archipelago off Florida's coast and left remains offering stark evidence that the arrival of humans can permanently change -- and eliminate -- life on what had been isolated islands, says a University of Florida researcher.
The unusual discovery of well-preserved fossils in a water-filled sinkhole called a blue hole revealed the bones of landlubbing crocodiles and tortoises that did not survive human encroachment, said David Steadman, a UF ornithologist and the lead author of a paper published by the Proceedings of the National Academy of Sciences.
"The climate and environmental conditions back then weren't much different from those of today," said Steadman, who works at the Florida Museum of Natural History on the UF campus. "The big difference is us. When people got to the island, there was probably nothing easier to hunt than tortoises so they cooked and ate them. And they got rid of the crocodiles because it's tough to have kids playing at the edge of the village where there are terrestrial crocodiles running around."
The first entire fossilized skeletons of a tortoise and a crocodile found anywhere in the West Indies were uncovered from Sawmill Sink on Great Abaco Island in the Bahamas, along with bones of a lizard, snakes, bats and 25 species of birds, as well as abundant plant fossils.
Radiocarbon analyses date the bones at between 1,000 and 4,200 years old with the youngest fossil being that of a human tibia, he said. The fossils are the best preserved of any ever found in the Bahamas because of their unusual location in the deep saltwater layer of the sinkhole that contains no oxygen, which normally would feed the bacteria and fungi that cause bones to decay, Steadman said. Expert diver Brian Kakuk and other skilled scuba divers retrieved the fossils from various places along the floor and walls of the blue hole, which contains salt water covered by a layer of freshwater.
"The fossils from Sawmill Sink open up unparalleled opportunities for doing much more sophisticated work than ever before in reconstructing the ancient plant and animal communities of the Bahamas," Steadman said. "It helps us to understand not only how individual species evolve on islands, but how these communities changed with the arrival of people because we know that changes in the ecosystem are much more dramatic on islands than they are on continents."
There are many blue holes on Abaco and other Bahamian islands, but this is the first to be the site of a sophisticated fossil excavation, Steadman said. Although the Bahamian government has gone to great lengths to protect its coastline, blue holes with their submerged cave passages have received little attention as a marine resource, he said.
The fossil site is especially valuable because of the presence of fossilized plants -- leaves, twigs, flowers, fruits and seeds -- pollen and spores, and vertebrates, giving evidence of both the island's flora and fauna, Steadman said.
"In a typical vertebrate fossil site, you identify the species of vertebrates -- reptiles, birds or mammals -- and based on that identification you speculate what the habitat might have been," he said. "For the first time here in the West Indies, we have here on Abaco plant fossils right in with the vertebrates, so we can reconstruct the habitats in a much more sophisticated way."
For instance, because bracken ferns are one of the first plants to recolonize after a fire, the presence of their spores would indicate regular burning in prehistoric times and indicate that an area was grassland. Evidence for this also comes from the numerous fossils of burrowing owls or meadow larks, which prefer open habitats, he said.
Among the excavation's findings are that the land-roaming Cuban crocodile lived in the Bahamas until humans arrived, Steadman said. "People tend to think of crocodiles as aquatic and certainly most of them are, but in the Bahamas where there is no fresh water, the crocodile became a terrestrial predator," he said.
The collaborative project includes Bahamian scientists Nancy Albury, Keith Tinker and Michael Pateman, as well as paleontologist Gary Morgan of the New Mexico Museum of Natural History.
Adapted from materials provided by University of Florida.

Fausto Intilla

Monday, December 3, 2007

Dinosaur Mummy Found With Fossilized Skin And Soft Tissues


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ScienceDaily (Dec. 3, 2007) — The amazing discovery of one of the finest and rarest dinosaur specimens ever unearthed -- a partially intact dino mummy found in the Hell Creek Formation Badlands of North Dakota was made by 16-year-old fossil hunter Tyler Lyson on his uncle's farm.
The story of the find, the excavation of the mummy and its painstaking analysis by a team of international scientists is told in a new book from National Geographic, Grave Secrets of Dinosaurs: Soft Tissues and Hard Science, by internationally renowned British paleontologist Phillip Manning. This story examines a 65-million-year case so cold it's the hottest development in modern dinosaur hunting.
The fossilized remains, discovered in 1999, included not just bones, but fossilized soft tissues like skin, tendons and ligaments. Most importantly, it was the first-ever find of a dinosaur where the skin "envelope" had not collapsed onto the skeleton. This has allowed scientists to calculate muscle volume and mass for the first time. The fact that the skin is mostly intact allows for the exciting possibility that some of its original chemistry is still present.
The hadrosaur's backside is some 25 percent bigger than originally thought, enabling it to reach speeds of 28 mph - 10 mph faster than T. rex.
In this book Manning tells how he and Lyson --- now a geology and geophysics graduate student at Yale University -- and a multidisciplinary team of scientists embarked on an extraordinary project to excavate, preserve and analyze the ancient, enormous creature they have dubbed Dakota, using hard-won experience and cutting-edge technology to peer millions of years into prehistory. The result is an accurate and revealing portrait of a single dinosaur and the Late Cretaceous world in which it lived.
"The fossilized bones of the hadrosaur that Tyler discovered would allow the resurrection of many grave secrets locked in stone for more than 65 million years. The presence of rare soft-tissue structures would ensure that this fossil would become a member of a prehistoric elite - dinosaur mummies... Such remarkable fossils enable immense advances in our understanding of long-vanished lives and forgotten worlds," writes Manning in his prologue.
The book is more than a window into a far distant past. It's also an account of more than a century of paleontological pioneers and accomplishments and a portrait of the state of the art in modern paleontology. Manning takes readers on a chronological tour of the handful of dinosaur mummies that have teased the scientific community since 1908, when the first remarkably preserved example was discovered and excavated by the legendary Sternberg family.
Since then, similar discoveries from Italy to China and from North America to Patagonia have added to our knowledge and understanding of these remarkable fossils - but none so much as Dakota, whose secrets are being explored by Manning's international team of scientists who work with everything from tweezers, plaster and burlap to protein analysis, electron microscopes and the world's largest CT scanner -- originally built to examine NASA spacecraft -- as they excavate, record, analyze and interpret this incredible 8,000-pound find. The field research was partly funded by the National Geographic Society.
Among the exciting discoveries are a fleshy pad on Dakota's palm, hooves on its feet made of keratin, and well-preserved skin scales that vary in size and shape across the body, tail, arms and legs of the dinosaur.
The National Geographic Channel will air a documentary on this unprecedented find on Sunday, Dec. 9, at 9 p.m. ET/10 p.m. PT. "Dino Autopsy" offers never-before-seen details of what dinosaurs really looked like, as well as clues to how they moved and lived. Using the giant CT scanner provided by the Boeing company at a NASA facility, scientists will attempt to peer inside the preserved body and tail. Their findings may alter our perception of dinosaurs' body shape, skin texture and locomotion. Significant findings have already been made.
More details on the discovery of Dakota and dinosaurs in general can be found at http://www.nationalgeographic.com/dinosaurs.
Phillip Manning is a paleontologist, fossil hunter and writer. He has taught vertebrate paleontology and evolution at the universities of Liverpool and Manchester and currently heads the vertebrate paleontology research group at the University of Manchester (U.K.). He has worked in museums on the Isle of Wight, Clitheroe, York and Manchester and has held several curatorial positions. His research is both broad and diverse, and he has published papers on dinosaur tracks, theropod biomechanics, arthropod paleobiology, vertebrate locomotion and the evolution of respiration and flight in birds.
For young readers, the discovery is also chronicled in the recently released book Dinomummy: The Life, Death, and Discovery of Dakota, a Dinosaur from Hell Creek, by Phillip Manning (published by Kingfisher Books/Houghton Mifflin), which recounts Tyler Lyson's story about his dinosaur excavations as a teenager on his uncle’s ranch in North Dakota. Lyson now has a degree in biology and is currently studying for a PhD in paleontology at Yale University. He is the founder of the Marmouth Research Foundation, an organization dedicated to the excavation, preservation, and study of dinosaurs (see http://www.mrfdigs.com/).
Adapted from materials provided by National Geographic Society.

Fausto Intilla

Saturday, December 1, 2007

How Our Ancestors Were Like Gorillas


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ScienceDaily (Nov. 30, 2007) — New research shows that some of our closest extinct relatives had more in common with gorillas than previously thought. Dr Charles Lockwood, UCL Department of Anthropology and lead author of the study, said: "When we examined fossils from 1.5 to 2 million years ago we found that in one of our close relatives the males continued to grow well into adulthood, just as they do in gorillas. This resulted in a much bigger size difference between males and females than we see today.
"It's common knowledge that boys mature later than girls, but in humans the difference is actually much less marked than in some other primates. Male gorillas continue to grow long after their wisdom teeth have come through, and they don't reach what is referred to as dominant "silverback" status until many years after the females have already started to have offspring. Our research makes us think that, in this fossil species, one older male was probably dominant in a troop of females. This situation was risky for the males and they suffered high rates of predation as a result of both their social structure and pattern of growth."
The research used 35 fossilised specimens of Paranthropus robustus, an extinct relative of Homo sapiens which existed almost two million years ago. The fossils came from the palaeontological sites of Swartkrans, Drimolen and Kromdraii, all of which are in South Africa's Cradle of Humankind World Heritage Site near Johannesburg.
The research was inspired by earlier discoveries at Drimolen by Dr Andre Keyser, one of the co-authors of the study. Dr Colin Menter, from the University of Johannesburg and co-director of current fieldwork at Drimolen, explains: "Discoveries at this site showed us that sex differences in Paranthropus robustus were greater than we had previously thought. While there are some specimens from Drimolen that are just as large and robust as those from other sites like Swartkrans, there is a complete female skull that is distinctly smaller than the other, well-preserved specimens of the species."
Jacopo Moggi-Cecchi, based at the University of Florence and an expert on fossil teeth, participated in the study and says: "It takes large samples of fossils to ask questions about variation and growth, and it's really a tribute to fieldworkers such as Robert Broom and Bob Brain [who worked at Swartkrans] that this research could even take place. It's also an example of why we need to continue to look for fossils after we think we know what a species is -- more specimens allow us to answer more interesting questions. Even isolated teeth can give us new insights into what variation means."
Dr Lockwood adds: "The pattern of growth also gives a better understanding of who is male and who is female in this sample of skulls and it turns out that there are far more males in the fossil sample. Because fossils from the most prolific site, Swartkrans, are thought to have been deposited by predators such as leopards and hyenas, it appears that males were getting killed more often than females.
"Basically, males had a high-risk, high-return lifestyle in this species. They most likely left their birth groups at about the time they reached maturity, and it was a long time before they were mature enough to attract females and establish a new group. Some of them were killed by predators before they got the chance."
A final point made by the researchers is that not all fossil hominin samples show the same patterns, and it is quite possible that further work will reveal clear diversity in social structure between human ancestors, in the same way that one sees differences among apes such as chimpanzees, bonobos, gorillas, and orangutans. This research will help us to understand how human social structure evolved.
This research was published in the journal Science on November 30, 2007.
Research at Drimolen has been funded by the Leakey Foundation, the Department of Science and Technology in South Africa, the Italian Ministry of Foreign Affairs, and the Italian Cultural Institute in Pretoria. The Royal Society supported Charles Lockwood's work in South Africa.
Fossils are housed at the University of the Witwatersrand in Johannesburg and the Transvaal Museum (Northern Flagship Institution), Pretoria.
Adapted from materials provided by University College London.

Fausto Intilla