Ancient Egyptian Glassmaking Recreated

Source:

http://www.sciencedaily.com/releases/2007/12/071214094026.htm

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

www.oloscience.com

Andean Highlands In Chile Yield Ancient South American Armored Mammal Fossil

Source:

http://www.sciencedaily.com/releases/2007/12/071214002808.htm

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

www.oloscience.com

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

Source:

http://www.sciencedaily.com/releases/2007/12/071210214308.htm

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

www.oloscience.com

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

Source:

http://www.sciencedaily.com/releases/2007/12/071207091852.htm

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

www.oloscience.com

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

Source:

http://www.sciencedaily.com/releases/2007/12/071203173039.htm

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

www.oloscience.com

Dinosaur Mummy Found With Fossilized Skin And Soft Tissues

Source:

http://www.sciencedaily.com/releases/2007/12/071203103349.htm

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

www.oloscience.com

How Our Ancestors Were Like Gorillas

Source:

http://www.sciencedaily.com/releases/2007/11/071129143817.htm

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

www.oloscience.com

Petrified Velvet Worms From 425 Million Years Ago Reveal True Ecology Of Distant Past

Source:

http://www.sciencedaily.com/releases/2007/11/071126121836.htm

ScienceDaily (Nov. 26, 2007) — University of Leicester Geologist Dr Mark Purnell, with Canadian colleagues, reported, in the journal Geology, a new, exceptionally preserved deposit of fossils in 425 million year old Silurian rocks in Ontario.

The fossils include complete fish (only the second place on earth where whole fish of this age have been found), various shrimp and worm like creatures, including velvet-worms, which look (in Dr Purnell’s words) “rather like a dozen headless Michelin men dancing a conga.”
The velvet worms were deflated slightly by a little early rotting, but within days of dying these animals had been transformed to the mineral calcium phosphate. This preserved them as beautiful petrified fossils, showing the wonderful detail of their bodies, including coloured stripes. This Canadian deposit is unusual even for sites of exceptional preservation because it also includes normal shelly fossils. From this it is possible to be sure that the conditions in which all the animals were living were not much different to normal nearshore seas of the Silurian period.
Dr Purnell commented: “It provides us with our best view of what lived together in such environments 425 million years ago, and our best information for understanding how life on earth at that time was different to today.
“If people think of a fossil, they will undoubtedly be thinking of something with a hard skeleton or shell of some sort, and it is true that the vast majority of fossil are what in today’s world we call sea shells. But imagine trying to understand the biodiversity and ecology of a submarine seaside ecosystem with only the remains of sea shells to go on.
“All the variety of worms that crawl over and into the sand would be unknown, as would all the shrimpy things that scurry over the surface. We would have only a very partial view of the real biological picture.
“This is what palaeontologists are faced with when they try to reconstruct the history and past ecology of life on Earth, because everything without a shell very quickly, within hours or days, rots away to nothing, leaving no trace that it ever existed.”
Fortunately, there are a few special rock deposits scattered around the world that preserve fossilised traces of those things that normally rot away. These are known to palaeontologists as sites of exceptional preservation, but they are, Dr Purnell says, tricky to interpret precisely because they are exceptional.
“They require very unusual environmental conditions in order to slow down the decomposition of soft tissues, such as muscle and skin, and rapidly transform them into geologically stable minerals that will survive as fossils for millions of years.
“The difficulty for geologists has been that if the conditions are exceptionally unusual, is that also true of the preserved fauna or is it a more typical example? That is something our latest find has helped resolve.”
Adapted from materials provided by University of Leicester.

Fausto Intilla

www.oloscience.com

Giant Fossil Sea Scorpion Bigger Than Man

Source:

http://www.sciencedaily.com/releases/2007/11/071120195710.htm

ScienceDaily (Nov. 21, 2007) — The discovery of a giant fossilised claw from an ancient sea scorpion indicates that when alive it would have been about two and a half meters long, much taller than the average man.

This find, from rocks 390 million years old, suggests that spiders, insects, crabs and similar creatures were much larger in the past than previously thought.
Dr Simon Braddy from the Department of Earth Sciences at the University of Bristol, co-author of an article about the find, said, 'This is an amazing discovery. We have known for some time that the fossil record yields monster millipedes, super-sized scorpions, colossal cockroaches, and jumbo dragonflies, but we never realised, until now, just how big some of these ancient creepy-crawlies were.'
The claw was discovered by one of Dr Braddy's co-authors*, Markus Poschmann, in a quarry near Prüm in Germany.
Poschmann described finding the fossil: "I was loosening pieces of rock with a hammer and chisel when I suddenly realised there was a dark patch of organic matter on a freshly removed slab. After some cleaning I could identify this as a small part of a large claw. Although I did not know if it was more complete or not, I decided to try and get it out. The pieces had to be cleaned separately, dried, and then glued back together. It was then put into a white plaster jacket to stabilise it."
The claw is from a sea scorpion (eurypterid) Jaekelopterus rhenaniae that lived between 460 and 255 million years ago. It is 46 centimetres long, indicating that the sea scorpion to which it belonged was around 2.5 metres (8 feet) long -- almost half a metre longer than previous estimates for these arthropods and the largest one ever to have evolved.
Eurypterids are believed to be the extinct aquatic ancestors of scorpions and possibly all arachnids.
Some geologists believe that giant arthropods evolved due to higher levels of oxygen in the atmosphere in the past. Others, that they evolved in an 'arms race' alongside their likely prey, the early armoured fish.
'There is no simple single explanation', explains Braddy. 'It is more likely that some ancient arthropods were big because there was little competition from the vertebrates, as we see today. If the amount of oxygen in the atmosphere suddenly increased, it doesn't mean all the bugs would get bigger.'
*The research is published online in the Royal Society's journal Biology Letters.
Adapted from materials provided by University of Bristol.

Fausto Intilla

www.oloscience.com

Maya Politics Likely Played Role In Ancient Large-game Decline

Source:

http://www.sciencedaily.com/releases/2007/11/071114200920.htm

ScienceDaily (Nov. 20, 2007) — A University of Florida study is the first to document ancient hunting effects on large-game species in the Maya lowlands of Central America, and shows political and social demands near important cities likely contributed to their population decline, especially white-tailed deer.

Additional evidence from Maya culture and social structure at the end of the Classic period (approximately 250 to 800 A.D) strongly supports this assertion.
“We’re finding declines specifically in large-game species, and particularly in the species that were politically and socially important to the Maya,” Emery said. “The politically powerful elite Maya had preferential access to large game, and white-tailed deer were especially important to the Maya as food and for their symbolic power.”
Emery tracked the proportion of large-game animals to all vertebrate species over time, using 78,928 animal bones found at 25 Maya archaeological sites. To tease apart specific hunting effects, she also tracked the proportion of white-tailed deer to all vertebrates. Her samples spanned 2,500 years, from about 1000 B.C. to 1500 A.D.
This period includes the collapse of the lowland Maya political and social order and the final period of Spanish colonization. Her study, funded by the National Science Foundation, is the first regional analysis of this area to interpret how humans impacted animal populations based on archaeological data of animal use by humans. She used both her own original data and existing published data.
“The data suggests the game decline was caused primarily by hunting pressure since the reduction in numbers was recorded for large vertebrates as opposed to just animals sensitive to the disappearance of forest cover or those sensitive to climate changes,” Emery said. “But the effects of hunting pressure were undoubtedly exacerbated by deforestation and climate change since there is also documented evidence for these changes at the same time.”
Emery said not all sites showed large-game declines despite high human population, and that the declines were most noticeable at regional capitals and large cities.
“The capital cities were home to a large and top-heavy ruling class who demanded that the regions’ hunters provide them with large quantities of the best cuts of favorite meats from large game, and particularly the white-tailed deer,” Emery said. “They also demanded large numbers of symbolically important species such as white-tailed deer and large wild cats like jaguar and puma, since these species were used as symbolic displays of their wealth and power, and were used in ritual interactions with the deities.”
Deer also were important theatrically because actors wore costumes to portray the predator-prey relationship.
The power of the noble classes and the king was based on their perceived abilities to control ecology, but Emery said several negative environmental situations converged simultaneously, likely contributing to the collapse of Maya political stability starting around 1,200 years ago. According to current Maya archaeological theory, Maya demand for wood used in building finishes such as lime plaster combined with an exploding population base that cleared more and more land for agriculture — resulting in deforestation. Concurrent climate change resulted in a 200-year drought which further curtailed forest regrowth.
“The rulers’ response to the environmental degradation may have been to demand more large game and more deer to use in feasts and rituals where they appealed to deities for help and also to prove their status,” Emery said. “As the valued resources became more scarce, they made more demands to obtain them to prove and reinforce their power.”
Their demand for large game was not extreme enough to cause extinction or local exterminations, an important finding. Emery said this indicates that over the 2,500 years of this study, the ancient Maya were generally careful of their animal resources.
Brown University ancient Maya scholar Stephen Houston said Emery’s “breadth of expertise” allowed her to tackle such an important review of Maya animal use.
“The lack of extinctions shows that the Maya impact on parts of their environment was not as profound as some have thought,” Houston said. “That is, we don’t see utter devastation to the extent that species disappeared entirely. But Emery also confirms that the Maya went after high-value, prestigious meats like deer and, through vigorous hunting, that they found such game harder and harder to find.”
The study by Florida Museum of Natural History Assistant Curator of Environmental Archaeology Kitty Emery appears in the Oct. 31 issue of the Journal for Nature Conservation.
Adapted from materials provided by University of Florida.

Fausto Intilla

www.oloscience.com

Dinosaur From Sahara Ate Like A 'Mesozoic Cow'

Source:

http://www.sciencedaily.com/releases/2007/11/071115113252.htm

ScienceDaily (Nov. 16, 2007) — A 110-million-year-old dinosaur that had a mouth that worked like a vacuum cleaner, hundreds of tiny teeth and nearly translucent skull bones has been discovered.

Found in the Sahara by National Geographic Explorer-in-Residence Paul Sereno, paleontologist and professor at the University of Chicago, the dinosaur is a plant eater known as Nigersaurus taqueti. Originally named by Sereno and his team in 1999 with only a few of its distinctive bones in hand, Nigersaurus has emerged as an anatomically bizarre dinosaur.
Nigersaurus, a younger cousin of the more familiar North American dinosaur Diplodocus, is small for a sauropod, measuring only 30 feet in length. It managed to sustain its elephant-sized body with a featherweight skull armed with hundreds of needle-shaped teeth, said Sereno. Barely able to lift its head above its back, Nigersaurus operated more like a Mesozoic cow than a reptilian giraffe, mowing down mouthfuls of greenery that consisted largely of ferns and horsetails.
The dinosaur's oddest feature was a broad, straight-edged muzzle, which allowed its mouth to work close to the ground. Unlike any other plant eater, Nigersaurus had more than 50 columns of teeth, all lined up tightly along the front edge of its squared-off jaw, forming, in effect, a foot-long pair of scissors.
A CT scan of the jaw bones showed up to nine "replacements" stacked behind each cutting tooth, so that when one wore out, another immediately took its place. There were more than 500 teeth in total, with a new tooth in each column joining the scissors edge every month. "Among dinosaurs," Sereno said, "Nigersaurus sets the Guinness record for tooth replacement."
Sereno and coauthors write in PLoS One that Nigersaurus' downwardly deflected muzzle may characterize most diplodocoids, such as North America's Diplodocus. "Some of these unusual sauropods thrived to become the pre-eminent ground-level feeders of the Mesozoic," said coauthor Jeffrey Wilson, assistant professor at the University of Michigan.
CT scanning allowed Sereno and team to look inside the dinosaur's braincase. There, small canals of the brain's balancing organ revealed the habitual pose of the head. Reconstructed from CT scans, these canals showed that the muzzle of Nigersaurus angled directly toward the ground, unlike the forward-pointing snouts of most other dinosaurs. This feature, along with unusual wear facets on the animal's teeth, led Sereno and colleagues to conclude that Nigersaurus largely fed by cropping plants near the ground.
Coauthor Lawrence Witmer, professor at Ohio University, who imaged the brain and organ of equilibrium, said, "What we have here is the first good look at a sauropod brain, and it has important things to say about this animal's posture and behavior."
Jaw design was not Nigersaurus' only odd characteristic: It had a backbone that was more air than bone. "The vertebrae are so paper-thin that it is difficult to imagine them coping with the stresses of everyday use -- but we know they did it, and they did it well," said Wilson, who was an expedition team member.
The first bones of Nigersaurus were picked up in the 1950s by French paleontologists, though the species was not named. Sereno and his team honored this early work by naming the species after French paleontologist Philippe Taquet. Sereno's team member Didier Dutheil first spotted the skull bones of Nigersaurus in 1997, and on that expedition and the next, teams collected about 80 percent of the skeleton.
The fossil area, in the present-day nation of Niger, was home to the enormous extinct crocodilian nicknamed SuperCroc as well as the likely fish eater Suchomimus, both found by Sereno and both on the prowl for Nigersaurus some 110 million years ago. Then, the African continent was just beginning to free itself of land connections it inherited as a central part of the ancient supercontinent Pangaea. Nigersaurus' closest relative has been found recently in Spain.
Coauthors on the PLoS One paper include Jeffrey A. Wilson, Lawrence M. Witmer, John A. Whitlock, Abdoulaye Maga, Oumarou Ide and Timothy A. Rowe. Funders of the research in addition to the National Geographic Society include The David and Lucile Packard Foundation, the Pritzker Foundation and the Women's Board of the University of Chicago.
Citation: Sereno PC, Wilson JA, Witmer LM, Whitlock JA, Maga A, et al (2007) Structural Extremes in a Cretaceous Dinosaur. PLoS One 2(11): e1230.doi:10.1371/journal.pone.0001230
Details of the dinosaur's anatomy and lifestyle will be published Nov. 21, 2007, (available Nov. 15) in PLoS One, the online journal from the Public Library of Science, as well as in the December 2007 issue of National Geographic magazine, "Extreme Dinosaurs."
Sereno's research was partly funded by the National Geographic Society.
Adapted from materials provided by Public Library of Science.

Fausto Intilla

www.oloscience.com

More Than Just a Pretty Face From History

Source:

http://www.nytimes.com/2007/11/11/weekinreview/11wilford.html?ref=science

By JOHN NOBLE WILFORD
Published: November 11, 2007

The first public showing of the face of the boy pharaoh Tutankhamun, last week, exposed more than cracked, leathery skin and his buckteeth. (Gene Tierney’s overbite was much more fetching.) Archaeologists also detected a new feature, the hint of a Tut smile, transfiguring a regal mummy from antiquity into a human being with emotions perhaps like those of people today. The first reaction of Zahi Hawass, Egypt’s head of antiquities, was unscientific. The face, he said, “has magic; it has mystery; it has beauty.”
The search for identifiable affinities, if only a smile, with people long ago may account for our fascination with mummies and hominid skulls. History is full of dynasties and armies, documents and artifacts, but lacks, especially in deep time, the flesh and sinew of shared humanity. There is some felt need to put a face on the past.
Even ancient Egypt, which left arguably the most expressive remains of an early civilization, has frustrated scholars. Its temples and tombs are decorated with sculpture, portraits and other paintings. But the art is more or less idealized. Though the faces may bear some likeness to the person in life, the stylized renderings speak to posterity, conveying the divinity and serenity of immortal kings and queens.
Some representations lead to contradictory impressions. A famous bust of the powerful queen Nefertiti shows a beautiful swanlike neck and high cheek bones. In others, she appears haggard. Even Nefertiti must have had bad days.
Emily Teeter, an Egyptologist at the University of Chicago, said that when you had the body of a person and could also look into the face, then some of the personality may emerge. This, she said, “goes beyond representational art and really conceptualizes history.”
Tut’s unwrapped remains, previously seen by only a small number of people, will now be on display to the public, in a climate-controlled glass case in his tomb. A few other mummified royal faces are also well preserved. Matthew Adams, an Egyptologist at the Institute of Fine Arts of New York University, said the character of Seti I, the pharaoh from the 13th century B.C. who was father of Ramses II, seemed written in his noble visage. “People have been influenced by that face in their interpretation of Seti as having been a good, wise king,” he said. “We are really projecting our own esthetic on him.”
In the United States, where history is more recent, the past is more reliably evoked through portraits and photography. See Washington’s set jaw and think of resolute leadership, not to mention those ill-fitting dentures. Look upon Lincoln’s craggy, brooding face and realize something of the burden he bore in a country divided. They are reminders of how much of remote antiquity is unrecoverable.
An enigmatic smile may be as close as people today will ever get to knowing the boy pharaoh who reigned 3,300 years ago and died at 19. The bare bones of the hominid Lucy are expressionless. Cleopatra, who charmed the powerful, remains a mystery; coins that show her large, unattractive nose call into question her reputation for beauty.
And who would not give their last drachma for a look at Helen of Troy, whose face launched a thousand ships?

Fausto Intilla

www.oloscience.com

Cultic City And Fortress Unearthed In Southern Turkey

Source:

http://www.sciencedaily.com/releases/2007/10/071030133030.htm

ScienceDaily (Nov. 5, 2007) — New excavations conducted by the University of Tübingen (Germany) and the Onsekiz Mart University of Çanakkale (Turkey) at the site of Sirkeli Höyük near Adana (southern Turkey) have revealed the remains of a massive bastion fortification dating to the Hittite Imperial Period (ca. 1300 BC). Sirkeli Höyük, one of the largest settlement mounds in Cilicia during the Bronze- and Iron Ages, was already known to archaeologists and historians because of two Hittite rock reliefs located at the site.

The better preserved rock relief of the two shows the Hittite King Muwatalli II (ca. 1290–1272 BC), opponent of Pharaoh Ramesses II in the famous Battle of Qadesh in Syria and is thus the oldest Hittite rock relief known so far.
On the upside of the rock, just above the reliefs, various shallow pits or basins are found which apparently are to be connected with the reliefs and were used for libations in the course of cultic activities.
These pits were part of a larger cultic installation which also included a building to the west of the rock reliefs. This ensemble is thought to be a cultic installation for the Hittite King.
Excavations at the site were conducted between 1992-1997 by the Universities of Munich and Innsbruck. In 2006 excavations were resumed by the University of Tübingen and the University of Çanakkale. The project and its organization are based at the Institute of Near Eastern Archaeology and Assyriology at the University of Tübingen. The Institute of Prehistorical Archaeology and the Institute of Classical Archaeology are associated with the project.
At the University of Çanakkale the project is based at the Institute of Prehistorical Archaeology, Near Eastern Archaeology and Classical Archaeology. The project is carried out under the patronage of the Bavarian Academy of Sciences.
In the course of the first two campaigns conducted in 2006 and 2007 the massive fortification bastion in the north-western part of the city was excavated. Finds made within the complex show that the building was constructed during the Late Bronze Age (1500-1200 B.C.) and apparently modified and re-used during the Iron Age (1200-600 B.C.). Later, the surrounding area of the mound was occupied by Hellenistic buildings. The finds reveal that the site was engaged in cultural exchange and trade with the Levant, the Aegean and different regions of Anatolia in the 2nd and 1st millennium B.C.
The site of Sirkeli Höyük may possibly also be identified with the ancient cultic city of Lawazantiya which is known to have been the home town of Hittite Queen Puduhepa, wife of King Hattusili III (ca. 1265-1240 B.C.).
Adapted from materials provided by Tuebingen University.

Fausto Intilla

www.oloscience.com

Earliest Evidence Of Modern Humans Detected

Source:

http://www.sciencedaily.com/releases/2007/10/071017145252.htm

Science Daily — Evidence of early humans living on the coast in South Africa, harvesting food from the sea, employing complex bladelet tools and using red pigments in symbolic behavior 164,000 years ago, far earlier than previously documented, is being reported in the journal Nature.

The international team of researchers reporting the findings include Curtis Marean, a paleoanthropologist with the Institute of Human Origins at Arizona State University and three graduate students in the School of Human Evolution and Social Change.
"Our findings show that at 164,000 years ago in coastal South Africa humans expanded their diet to include shellfish and other marine resources, perhaps as a response to harsh environmental conditions," notes Marean, a professor in ASU's School of Human Evolution and Social Change. "This is the earliest dated observation of this behavior."
Further, the researchers report that co-occurring with this diet expansion is a very early use of pigment, likely for symbolic behavior, as well as the use of bladelet stone tool technology, previously dating to 70,000 years ago.
These new findings not only move back the timeline for the evolution of modern humans, they show that lifestyles focused on coastal habitats and resources may have been crucial to the evolution and survival of these early humans.
Searching for beginnings
After decades of debate, paleoanthropologists now agree the genetic and fossil evidence suggests that the modern human species -- Homo sapiens -- evolved in Africa between 100,000 and 200,000 years ago.
Yet, archaeological sites during that time period are rare in Africa. And, given the enormous expanse of the continent, where in Africa did this crucial step to modern humans occur?
"Archaeologists have had a hard time finding material residues of these earliest modern humans," Marean says. "The world was in a glacial stage 125,000 to 195,000 years ago, and much of Africa was dry to mostly desert; in many areas food would have been difficult to acquire. The paleoenvironmental data indicate there are only five or six places in all of Africa where humans could have survived these harsh conditions."
In seeking the "perfect site" to explore, Marean analyzed ocean currents, climate data, geological formations and other data to pin down a location where he felt sure to find one of these progenitor populations: the Cape of South Africa at Pinnacle Point.
"It was important that we knew exactly where to look and what we were looking for," says Marean. This type of research is expensive and funding is competitive. Marean and the team of scientists who set out to Pinnacle Point to search for this elusive population, did so with the help of a $2.5 million grant from the National Science Foundation's Human Origins: Moving in New Directions (HOMINID) program.
Their findings are reported in the Nature paper "Early human use of marine resources and pigment in South Africa during the Middle Pleistocene." In addition to Marean, authors on the paper include three graduate students in ASU's School of Human Evolution and Social Change: Erin Thompson, Hope Williams and Jocelyn Bernatchez. Other authors are Miryam Bar-Matthews of the Geological Survey of Israel, Erich Fisher of the University of Florida, Paul Goldberg of Boston University, Andy I.R. Herries of the University of New South Wales (Australia), Zenobia Jacobs of the University of Wollongong (Australia), Antonieta Jerardino of the University of Cape Town (South Africa), Panagiotis Karkanas of Greece's Ministry of Culture, Tom Minichillo of the University of Washington, Ian Watts from London and excavation co-director Peter J. Nilssen of the Iziko South African Museum.
The Middle Stone Age, dated between 35,000 and 300,000 years ago, is the technological stage when anatomically modern humans emerged in Africa, along with modern cognitive behavior, says Marean. When, however, within that stage modern human behavior arose is currently debated, he adds.
"This time is beyond the range of radiocarbon dating, yet the dates on the finds published here are more secure than is typical due to the use of two advanced and independent techniques," Marean says.
Uranium series dates were attained by Bar-Matthews on speleothem (the material of stalagmites), and optically stimulated luminescence dates were developed by Jacobs. According to Marean, the latter technique dates the last time that individual grains of sand were exposed to light, and thousands of grains were measured.
Migrating along the coast
"Generally speaking, coastal areas were of no use to early humans -- unless they knew how to use the sea as a food source" says Marean. "For millions of years, our earliest hunter-gatherer relatives only ate terrestrial plants and animals. Shellfish was one of the last additions to the human diet before domesticated plants and animals were introduced."
Before, the earliest evidence for human use of marine resources and coastal habitats was dated about 125,000 years ago. "Our research shows that humans started doing this at least 40,000 years earlier. This could have very well been a response to the extreme environmental conditions they were experiencing," he says.
"We also found what archaeologists call bladelets -- little blades less than 10 millimeters in width, about the size of your little finger," Marean says. "These could be attached to the end of a stick to form a point for a spear, or lined up like barbs on a dart -- which shows they were already using complex compound tools. And, we found evidence that they were using pigments, especially red ochre, in ways that we believe were symbolic," he describes.
Archaeologists view symbolic behavior as one of the clues that modern language may have been present. The earliest bladelet technology was previously dated to 70,000 years ago, near the end of the Middle Stone Age, and the modified pigments are the earliest securely dated and published evidence for pigment use.
"Coastlines generally make great migration routes," Marean says. "Knowing how to exploit the sea for food meant these early humans could now use coastlines as productive home ranges and move long distances."
Results reporting early use of coastlines are especially significant to scientists interested in the migration of humans out of Africa. Physical evidence that this coastal population was practicing modern human behavior is particularly important to geneticists and physical anthropologists seeking to identify the progenitor population for modern humans.
"This evidence shows that Africa, and particularly southern Africa, was precocious in the development of modern human biology and behavior. We believe that on the far southern shore of Africa there was a small population of modern humans who struggled through this glacial period using shellfish and advanced technologies, and symbolism was important to their social relations. It is possible that this population could be the progenitor population for all modern humans," Marean says.
The research is detailed in the October 18 issue of Nature.
Note: This story has been adapted from material provided by Arizona State University.

Fausto Intilla

www.oloscience.com

Early Apes Walked Upright 15 Million Years Earlier Than Previously Thought, Evolutionary Biologist Argues

Source:

http://www.sciencedaily.com/releases/2007/10/071009212545.htm

Science Daily — An extraordinary advance in human origins research reveals evidence of the emergence of the upright human body plan over 15 million years earlier than most experts have believed. More dramatically, the study confirms preliminary evidence that many early hominoid apes were most likely upright bipedal walkers sharing the basic body form of modern humans.

Research from Harvard University¹s Museum of Comparative Zoology and from the Cedars Sinai Institute for Spinal Disorders connects several recent fossil discoveries to older fossils finds that have eluded adequate explanation in the past. The report deals with the "homeotic" genetic mechanisms that encode anatomical assembly in the embryo, and their relevance to a series of discoveries of hominoid fossil vertebrae.
The report analyses changes in homeotic embryological assembly of the spine in more than 200 mammalian species across a 250 million year time scale. It identifies a series of modular changes in genetic assembly program that have taken place at the origin point of several major groups of mammals including the newly designated 'hominiform' hominoids that share the modern human body plan.
It concludes that a specific gene change ­ in the Pax system -- that generated the upright bipedal human body form -- may soon be identified. The various upright "hominiform" hominoids appear to share this morphogenetic innovation with modern humans. Homeotics concerns the embryological assembly program for midline repeating structures such as the human vertebral column and the insect body segments.
The critical event involves a dramatic embryological change unique to the human lineage that was not previously understood because the unusual human condition was viewed as "normal."
"From an embryological point of view, what took place is literally breathtaking," says Dr. Aaron Filler, a Harvard-trained evolutionary biologist and a medical director at Cedars Sinai Medical Center's Institute for Spinal Disorders.
In most vertebrates (including most mammals), he explains, the dividing plane between the front (ventral) part of the body and the back (dorsal) part is a "horizontal septum" that runs in front of the spinal canal. This is a fundamental aspect of animal architecture. A bizarre birth defect in what may have been the first direct human ancestor led to the "transposition" of the septum to a position behind the spinal cord in the lumbar region. Oddly enough, this configuration is more typical of invertebrates.
The mechanical effect of the transposition was to make horizontal or quadrupedal stance inefficient. "Any mammal with this set of changes would only be comfortable standing upright. I would envision this malformed young hominiform -- the first true ancestral human -- as standing upright from a young age while its siblings walked around on all fours."
The earliest example of the transformed hominiform type of lumbar spine is found in Morotopithecus bishopi an extinct hominoid species that lived in Uganda more than 21 million years ago. "From a number of points of view," Filler says, "humanity can be redefined as having its origin with Morotopithecus. This greatly demotes the importance of the bipedalism of Australopithecus species such as Lucy (Australopithecus afarensis) since we now know of four upright bipedal species that precede her, found from various time periods on out to Morotopithecus in the Early Miocene."
Citation: Filler AG (2007) Homeotic Evolution in the Mammalia: Diversification of Therian Axial Seriation and the Morphogenetic Basis of Human Origins. PLoS One 2(10): e1019. doi:10.1371/journal.pone.0001019, http://www.plosone.org/doi/pone.0001019
Note: This story has been adapted from material provided by Public Library of Science.

Fausto Intilla

www.oloscience.com

Even Without Math, Ancients Engineered Sophisticated Machines

Source:

http://www.sciencedaily.com/releases/2007/10/071002144301.htm

Science Daily — Move over, Archimedes. A researcher at Harvard University is finding that ancient Greek craftsmen were able to engineer sophisticated machines without necessarily understanding the mathematical theory behind their construction.
Recent analysis of technical treatises and literary sources dating back to the fifth century B.C. reveals that technology flourished among practitioners with limited theoretical knowledge.
"Craftsmen had their own kind of knowledge that didn't have to be based on theory," explains Mark Schiefsky, professor of the classics in Harvard's Faculty of Arts and Sciences. "They didn't all go to Plato's Academy to learn geometry, and yet they were able to construct precisely calibrated devices."
The balance, used to measure weight throughout the ancient world, best illustrates Schiefsky's findings on the distinction between theoretical and practitioner's knowledge. Working with a group led by Jürgen Renn, Director of the Max Planck Institute for the History of Science in Berlin, Schiefsky has found that the steelyard--a balance with unequal arms--was in use as early as the fourth and fifth centuries B.C., before Archimedes and other thinkers of the Hellenistic era gave a mathematical demonstration of its theoretical foundations.
"People assume that Archimedes was the first to use the steelyard because they suppose you can't create one without knowing the law of the lever. In fact, you can--and people did. Craftsmen had their own set of rules for making the scale and calibrating the device," says Schiefsky.
Practical needs, as well as trial-and-error, led to the development of technologies such as the steelyard.
"If someone brings a 100-pound slab of meat to the agora, how do you weigh it?" Schiefsky asks. "It would be nice to have a 10-pound counterweight instead of a 100-pound counterweight, but to do so you need to change the balance point and ostensibly understand the principle of proportionality between weight and distance from the fulcrum. Yet, these craftsmen were able to use and calibrate these devices without understanding the law of the lever."
Craftsmen learned to improve these machines through productive use, over the course of their careers, Schiefsky says.
With the rise of mathematical knowledge in the Hellenistic era, theory came to exert a greater influence on the development of ancient technologies. The catapult, developed in the third century B.C., provides evidence of the ways in which engineering became systematized.
With the help of literary sources and data from archaeological excavations, "We can actually trace when the ancients started to use mathematical methods to construct the catapult," notes Schiefsky. "The machines were built and calibrated precisely."
Alexandrian kings developed and patronized an active research program to further refine the catapult. Through experimentation and the application of mathematical methods, such as those developed by Archimedes, craftsmen were able to construct highly powerful machines. Twisted animal sinews helped to increase the power of the launching arm, which could hurl stones weighing 50 pounds or more.
The catapult had a large impact on the politics of the ancient world.
"You could suddenly attack a city that had previously been impenetrable," Schiefsky explains. "These machines changed the course of history."
According to Schiefsky, the interplay between theoretical knowledge and practical know-how is crucial to the history of Western science.
"It's important to explore what the craftsmen did and didn't know," Schiefsky says, "so that we can better understand how their work fits into the arc of scientific development."
Schiefsky's research is funded by the National Science Foundation and the Max Planck Institute for the History of Science in Berlin.
Note: This story has been adapted from material provided by Harvard University.

Fausto Intilla
www.oloscience.com

Huge New Dinosaur Had A Serious Bite

Source:

http://www.sciencedaily.com/releases/2007/10/071003130907.htm

Science Daily — The newest dinosaur species to emerge from Grand Staircase-Escalante National Monument had some serious bite, according to researchers from the Utah Museum of Natural History at the University of Utah.

"It was one of the most robust duck-billed dinosaurs ever," said museum paleontologist Terry Gates, who is also with the U.'s Department of Geology and Geophysics. "It was a monster."
Researchers from the Utah museum, the national monument and California's Raymond M. Alf Museum of Paleontology unearthed fossils of this ancient plant-eater from the rocks of the Kaiparowits Formation. Researchers announced the name of the creature -- Gryposaurus monumentensis. (Gryposaurus means "hook-beaked lizard" and monumentensis honors the monument where the fossils were found.)
This duck-billed dinosaur dates to the Late Cretaceous Period 75 million years ago. "Gryposaurus monumentensis is probably the largest dinosaur in the 75-million-year-old Kaiparowits fossil ecosystem," said Alan Titus, paleontologist for the national monument.
Gates, lead author on the study, explained that this creature could have eaten just about any vegetation it stumbled across. "With its robust jaws, no plant stood a chance against G. monumentensis," he said.
Scott Sampson, another paleontologist with the Utah museum who was involved with the project, emphasized the massively-built skull and skeleton, referring to the animal as the "Arnold Schwarzenegger of duck-billed dinosaurs."
Finding the skull
In 2002, a team from the Alf Museum, in Claremont, Calif., located at the Webb School, discovered the site that contained the skull used to describe the new creature. Every summer, the California institution, the only nationally-accredited paleontology museum on a high school campus, gives Webb students and volunteers the chance to participate in scientific field work.
The California team was working a stretch of Grand Staircase that Utah researchers had not examined. Duncan Everhart, a Pennsylvania furniture maker, is credited with finding the skull.
Don Lofgren, curator of the Alf Museum, said the team received permission from the monument to dig deeper in 2003.
"We determined it was a skull sitting upside down with the jaw on top," he said.
Once Gates went out to take a look in 2004, he quickly realized the California team had a potentially-important find. The Alf Museum gave the Utah researchers permission to prepare and study the skull.
Titus noted the discovery of this new species was a team effort involving the Alf Museum, the Utah Museum of Natural History and the national monument.
"The cooperative effort put into its collection and research has truly been a model for scientific investigation on public lands," he said.
It wasn't until Utah researchers began working on the skull in 2005 that the full significance of the find began to emerge, Gates said.
The well-preserved skull was initially missing key pieces from the nose region. Fortunately, the California museum had collected a box full of eroded bones, including bits of the nose bone, which was critical for identifying the creature.
"I knew immediately that we had some species of Gryposaurus," Gates said.
A toothy beast
The creature's large number of teeth embedded in the thick skull is among the features that made G. monumentensis, as well as other closely related duck-billed dinosaurs, such a successful herbivore.
At any given time, the dinosaur had over 300 teeth available to slice up plant material. Inside the jaw bone, there were numerous replacement teeth waiting, meaning that at any moment, this Gryposaur may have carried more than 800 teeth.
"IIt was capable of eating most any plant it wanted to," Gates said. "Although much more evidence is needed before we can hypothesize on its dietary preferences."
While the diet is unknown, given the considerable size of the creature, the massive teeth and jaws are thought to have been used to slice up large amounts of tough, fibrous plant material.
The teeth may hold important clues the dinosaur's eating habits. The Utah museum plans to study the composition of the dinosaur teeth, which when compared to other plant-eating dinosaurs from the Kaiparowits Formation, will help researchers decipher differences in diet.
G. monumentensis is one of several new dinosaur species found in Grand Staircase, including: a Velociraptor-like carnivore named Hagryphus, a tyrannosaur, and several kinds of horned dinosaurs. In all, more than a dozen kinds of dinosaurs have been recovered from these badlands, and most represent species that are new to science.
"This is a brand new and extremely important window into the world of dinosaurs," said Sampson.
Under ideal circumstances, paleontologists will find the skull and other key bones at the same site. In this case, the head was the only thing they managed to find from where the Alf team searched.
Researchers believe the head of this particular Gryposaur likely rolled into a bend of a river, where it was partly buried. The right half of the head remained exposed to the river current, dislodging several bones before this side was buried as well.
In other parts of the monument, Utah researchers have excavated bones believed to be from the same species. Gates estimates G. monumentensis may have grown up to 30 feet long as an adult.
"As each new find such as this new Gryposaur is made," Titus said, "it is placed into the greater context of an entire ecosystem that has remained lost for eons, and is only now coming under scientific scrutiny."
Life in 'West America'
Around 75 million years ago, southern Utah differed dramatically from today's arid desert and redrock country. During much of the Late Cretaceous, a shallow sea split North America down the middle, dividing the continent into eastern and western landmasses.
In what Sampson terms "West America," G. monumentensis and its fellow dinosaurs lived in a narrow strip of land sandwiched between the seaway to the east and rising mountains to the west. Due in large part to the presence of the seaway, the climate was moist and humid.
Thanks to more than 100 years of fossil collection, scientists know more about the Cretaceous dinosaurs from North American than they do from any other time or continent on Earth, Sampson noted.
While G. monumentensis gulped down its greens and tried to avoid predatory tyrannosaurs down in Utah, closely related but different species of duck-billed dinosaurs were doing the same thing farther north, in places like Montana and Alberta, Canada.
The new Utah species is proving crucial for determining patterns of duck-billed dinosaur evolution and ecology during the Late Cretaceous of North America, Gates said. He added that "this calls for a re-evaluation of previous ideas about the evolution of duck-billed dinosaurs across the world."
Earlier explanations of dinosaurs undertaking long distance migrations have gone out the window. "Now we have to figure out how so many different kinds of giants managed to coexist in such small areas," said Sampson. "We're just beginning to unravel this story."
Bones from G. monumentensis are on display at Big Water Visitor Center in Grand Staircase-Escalante National Monument, and for a short time at the Utah Museum of Natural History before returning to the Alf Museum.
This research was published in the Oct. 3 issue of the Zoological Journal of the Linnean Society.
Note: This story has been adapted from material provided by University of Utah.

Fausto Intilla

www.oloscience.com

New Dinosaur Species Found In Montana

Source:

http://www.sciencedaily.com/releases/2007/09/070924104611.htm

Science Daily — A dinosaur skeleton found 24 years ago near Choteau has finally been identified as a new species that links North American dinosaurs with Asian dinosaurs. The dinosaur would have weighed 30 to 40 pounds, walked on two feet and stood about three feet tall. The fossil came from sediment that's about 80 million years old.

A paper on the finding was published in September's issue of the Journal of Vertebrate Paleontology, co-author Jack Horner said Friday after returning from Mongolia where he and his crew found 80 dinosaurs in a week. Horner is curator of paleontology at Montana State University's Museum of the Rockies. The paper's lead author was Brenda Chinnery, a former postdoctoral researcher with Horner.
Horner said he found the nearly-complete skeleton in 1983, but it was located in extremely hard rock and took a long time to prepare. He also had to wait about two decades before he found an expert who could identify it. That expert was Chinnery, who specializes in horned dinosaurs. Chinnery had worked for one of Horner's colleagues at Johns Hopkins University and then came to MSU. She left MSU about two years ago and is now a paleontologist at the University of Texas.
"I knew it was probably a new dinosaur, but it took someone that really knew what they were doing to be able to describe it," Horner said.
The dinosaur fossil has been stored in the Museum of the Rockies since its discovery, but it will be displayed this winter, Horner said. The skeleton has a reddish tinge because some of the original bone was replaced by jasper. It dates to the early part of the Late Cretaceous Period.
The dinosaur, nicknamed Cera, was named Cerasinops hodgskissi after landowner Wilson Hodgskiss. who gave him permission to collect the skeleton for the Museum of the Rockies, Horner said. The fossil was found about five miles south of Choteau, in a different area than the famed Egg Mountain site.
The C. hodgskissi is such a simple specimen that it's hard to describe in terms of distinguishing characteristics, Horner said. Tests, however, showed that it represents a very primitive species that shares characteristics of Neo-ceratopsian dinosaurs in North America and Asia. Ceratopsian dinosaurs have horns, but these do not.
Horner said he was looking at even more primitive dinosaurs on his recent trip to Mongolia. His team collected more than 80 skeletons, with 70 of them coming from one site. Last year, they collected 67 skeletons at the same site. The Mongolian project is a joint research project between MSU and Mongolia's Science and Technology University.
Note: This story has been adapted from a news release issued by Montana State University.

Fausto Intilla

www.oloscience.com

Who Went There? Matching Fossil Tracks With Their Makers

Source:

http://www.sciencedaily.com/releases/2007/09/070915092239.htm

Science Daily — Fossilized footprints are relatively common, but figuring out exactly which ancient creature made particular tracks has been a mystery that has long stumped paleontologists.

In the latest issue of the Journal of Vertebrate Paleontology, a team of researchers overcome this dilemma for the first time, and link a fossil trackway to a well-known fossil animal.
Sebastian Voigt, a trackway expert from the Institute of Geology, Freiberg University of Mining and Technology, Germany, and David Berman and Amy Henrici of the Carnegie Museum of Natural History, Pittsburgh, who study fossil skeletons, took a close look at an exceptional fossil collection from 290-million-year-old sediments of central Germany known as the Tambach Formation. The Bromacker locality in the Tambach Formation has been famous for its fossil footprints for well over a century, but “identifying the animals that made the tracks proved challenging,” commented Voigt.
Fortunately, the Bromacker locality offered clues to solving the problem for the paleontologists. Superbly detailed trackways were found in concert with exceptionally preserved skeletons, in the same sediments. “To have beautifully preserved trackways and skeletons at the same site is a unique situation for paleontologists — it provides a wonderful opportunity to better understand how these extinct animals lived,” noted Berman.
The team combined their expertise in anatomy and ichnology (the study of tracks) to match up the most common tracks with their makers. Detailed measurements of the tracks, combined with measurements of the legs, feet and backbones of the skeletal material allowed the team to pinpoint the trackmakers. The two most common skeletal fossils, Diadectes absitus and Orobates pabsti, grew to approximately 3 or 4 feet.
These closely related reptile-like creatures were some of the first four-legged plant eaters on land, and have no close living relatives. Their limb skeletons and size match them well to the Bromacker locality’s two most common types of trackway, scientifically named Ichniotherium cottae and Ichniotherium sphaerodactylum.
Sebastian Voigt said, “Now that we have matched the two most common skeletons to their trackways, it is time to turn our attention to the rarer animals. Our work opens new doors for delving into other paleobiological questions, including how Diadectes and Orobates walked.”
Note: This story has been adapted from a news release issued by Society of Vertebrate Paleontology.

Fausto Intilla

www.oloscience.com

New Evidence On The Role Of Climate In Neanderthal Extinction

Source:

http://www.sciencedaily.com/releases/2007/09/070912154630.htm

Science Daily — The mystery of what killed the Neanderthals has moved a step closer to resolution after an international study led by the University of Leeds has ruled out one of the competing theories -- catastrophic climate change -- as the most likely cause.

The bones of more than 400 Neanderthals have been found since the first discoveries were made in the early 19th century. The finds suggest the Neanderthals, named after the Neander Valley near Düsseldorf, where they were first recognized as an extinct kind of archaic humans, inhabited Europe and parts of western Asia for more than 100,000 years.
The causes of their extinction have puzzled scientists for years -- with some believing it was due to competition with modern humans, while others blamed deteriorating climatic conditions. But a new study recently published in Nature has shown that the Neanderthal extinction did not coincide with any of the extreme climate events that punctuated the last glacial period.
The research was led by Professor Chronis Tzedakis, a palaeoecologist at the University of Leeds, who explained: "Until now, there have been three limitations to understanding the role of climate in the Neanderthal extinction: uncertainty over the exact timing of their disappearance; uncertainties in converting radiocarbon dates to actual calendar years; and the chronological imprecision of the ancient climate record."
The team's novel method -- mapping radiocarbon dates of interest directly onto a well-dated palaeoclimate archive -- circumvented the last two problems, providing a much more detailed picture of the climate at the possible times of the Neanderthal disappearance.
The researchers applied the new method to three alternative sets of dates for the timing of the Neanderthal extinction from Gorham's Cave, Gibraltar, a site which is thought to have been occupied by some of the latest surviving Neanderthals:
a set of generally accepted but older dates (around 30-32,000 radiocarbon years ago)
newly-suggested younger dates (around 28,000 radiocarbon years ago)
more contentious dates (around 24,000 radiocarbon years ago).
The team showed that during the first two sets of dates, Europe was experiencing conditions similar to the general climatic instability of the last glacial period -- conditions the Neanderthals had already proved able to survive.
The much more controversial date of around 24,000 radiocarbon years ago placed the last Neanderthals just before a large expansion of ice sheets and the onset of cold conditions in northern Europe. "But at that time, Gibraltar's climate remained relatively unaffected, perhaps as a result of warm water from the subtropical Atlantic entering the western Mediterranean," explained palaeoceanographer Isabel Cacho of the University of Barcelona.
"Our findings suggest that there was no single climatic event that caused the extinction of the Neanderthals," concludes palaeonthropologist Katerina Harvati of the Max Planck Institute for Evolutionary Anthropology. "Only the controversial date of 24,000 radiocarbon years for their disappearance, if proven correct, coincides with a major environmental shift. Even in this case, however, the role of climate would have been indirect, by promoting competition with other human groups."
The work also has wider implications for other studies, as paleoclimatologist Konrad Hughen of the Woods Hole Oceanographic Institution explained: "Our approach offers the huge potential to unravel the role of climate in critical events of the recent fossil record as it can be applied to any radiocarbon date from any deposit."
The article Placing late Neanderthals in a climatic context (Tzedakis, P.C., Hughen, K.A., Cacho, I. & Harvati, K) is published in Nature on September 13. The study was conducted by Chronis Tzedakis (University of Leeds); Konrad Hughen (Woods Hole Oceanographic Institution); Isabel Cacho (University of Barcelona); Katerina Harvati (Max Planck Institute for Evolutionary Anthropology).
Note: This story has been adapted from a news release issued by University of Leeds.

Fausto Intilla

www.oloscience.com

Angkor -- Medieval 'Hydraulic City' -- Unwittingly Engineered Its Environmental Collapse

Source:

http://www.sciencedaily.com/releases/2007/09/070905145001.htm

Science Daily — The architects of Cambodia’s famed Angkor – the world's most extensive medieval "hydraulic city" – unwittingly engineered its environmental collapse, says research by UNSW scientists and a team of international scholars.

This revelation, published in the Proceedings of the National Academy of Science, supports a disputed hypothesis by French archaeologist Bernard-Philippe Groslier, who 50 years ago suggested that the vast medieval settlement of Angkor was defined, sustained, and ultimately overwhelmed by over-exploitation and the environmental impacts of a complex water-management network.
A succession of monarchs ruled the Angkor area from about 800 AD, producing the architectural masterpieces and sculpture now preserved as a World Heritage site. By the 13th century the civilisation was in decline, and most of Angkor was abandoned by the early 15th century, apart from Angkor Wat, the main temple, which remained a Buddhist shrine.
Groslier surmised that a network of roads, canals and irrigation ponds established between the 9th and 16th centuries proved too vast to manage. He argued that extensive land clearing for rice fields supporting up to a million people living beyond Angkor's walled city produced serious ecological problems, including deforestation, topsoil degradation and erosion.
Latter-day archaeologists disputed Groslier’s view because he was unable to support his hypothesis with empirical data about the landscape beyond Angkor's central temple complex.
Using modern day aerial photography and high-resolution ground-sensing radar, the international research team, including UNSW’s Professor Tony Milne, studied an area of nearly 3000 square kilometres, confirming Groslier's hypothesis by correlating their images to existing maps, topographic data sets and supporting information from extensive ground-based archaeological investigations.
The team discovered more than 1000 man-made ponds and at least 74 more temple sites in the Angkor region, revealing ruins covering an area of 1000 square kilometres.
The study's radar images were acquired from NASA via an airborne imaging radar (AIRSAR) data instrument capable of accurately reconstructing surface structures through cloud cover.
"The instrument can produce high-resolution images detecting surface structures as small as 20 cms in height and distinguish very subtle differences in surface vegetation and soil moisture,” says Professor Milne from the School of Biological, Earth and Environmental Sciences.
"This was of particular use in uncovering the archaeological landscape at Angkor. The distinctive spatial patterning of features manifests itself primarily in slight variations in topographic relief. This also influences the amplitude or 'brightness' of the radar signal returned to the sensor.”
“Both the topographic relief and the surface brightness can be helpful in identifying the possible location of former roads, canals and rice fields,” says Professor Milne. "When excavations were carried out, they prove to be the site of a canal or temple moat”.
Note: This story has been adapted from a news release issued by University Of New South Wales.

Fausto Intilla

www.oloscience.com