Paleontology news

Evidence is weak for tropical rainforest 65 million years ago in Africa's low-latitudes

2010-10-22T17:37:00.002+02:00

The landscape of Central Africa 65 million years ago was a low-elevation tropical belt, but the jury is still out on whether the region's mammals browsed and hunted beneath the canopy of a lush rainforest. The scientific evidence for a tropical rainforest at that time is weak and far from convincing, says paleobotanist Bonnie F. Jacobs at Southern Methodist University in Dallas.

Fossil pollen from Central and West Africa provide no definitive evidence for communities of rainforest trees at the beginning of the Cenozoic, says Jacobs, an expert in the paleobotany of Africa soon after dinosaurs had gone extinct. It was the start of the age of mammals, and Africa was largely an island continent.

Many Cenozoic mysteries remain to be solved

The rainforest mystery is characteristic of the scientific uncertainty and unknowns surrounding Africa's ancient flora during the period called the Cenozoic. There are large gaps in the fossil record, says Jacobs, a co-author of "A Review of the Cenozoic Vegetation History of Africa." She is an associate professor in SMU's Roy M. Huffington Department of Earth Sciences.

The review, a chapter in "Cenozoic Mammals of Africa" (University of California Press, 2010), is the first of its kind since 1978 to review and interpret the Cenozoic paleobotanical record of Africa with paleogeographic maps showing paleobotanical site distributions through time. Jacobs co-authored the paper with Aaron D. Pan, a paleobotanist at the Fort Worth Museum of Science and History, and Christopher R. Scotese, in the Earth Sciences Department at the University of Texas at Arlington.

The 1008-page "Cenozoic Mammals of Africa" is the first comprehensive scientific reference of its kind since 1978, comprising 48 chapters by 64 experts. The volume summarizes and interprets the published fossil research to date of Africa's mammals, tectonics, geography, climate and flora of the past 65 million years.

Details sparse, but big picture emerges for past 65 million years

Paleobotanical data for Africa are generally meager and uneven for the Cenozoic, according to Jacobs and her co-authors.

In an original series of maps, they chart each Cenozoic Africa paleobotanical locale described in the published research to date. There are a mere 82 sites in all. Most of the sites date to 50 million years ago. Fewer date to 20 million, 30 million, 10 million and — perhaps most important — 2 million years ago, when the human family was evolving.

"Africa is disappointingly undersampled," say Jacobs and her colleagues. "This vast continent, roughly three times the area of the United States, has so far been documented by only a handful of Paleogene plant and vertebrate localities, and it has a Neogene record heavily biased toward the depositional basins of the East African Rift."

Shift from descriptive to analytic approach driven by holistic view

For a continent so important for its role in the evolution of mammals, the scarcity of plant fossil data stands in sharp contrast.

"As impressive as is the contemporary mammalian diversity of Africa, it is dwarfed by that of the Cenozoic," write the volume's editors, paleozoologist Lars Werdelin, the Swedish Museum of Natural History, and paleontologist William Joseph Sanders, the University of Michigan. Africa today represents 20 percent of the world's land mass, is the only continent to occupy both the north and south temperate zones, and is home now to more than 1,100 mammalian species, they write in the introduction.

Africa's paleobotanical record is key to a holistic understanding of ancient mammals, says H.B.S. Cooke in the preface. A mammal expert, Cooke was editor of the earlier 1978 scientific reference, "Evolution of African Mammals" (Harvard University Press).

"Most striking over the past years has been a shift in studying fossils from a largely descriptive taxonomy to a more analytical approach, including consideration of faunal associations, their distribution in time and space, and the environmental and climatic factors that prevailed and changed through time," Cooke writes in the preface to the new book. " … African prehistory has become more a study of paleobiology than mere paleontology."

To view a map or images of Cenozoic leaf fossils from Jacobs' field work in Africa go to SMU Research on flickr.

More scientific exploration needed to fill gaps

Scientific exploration to learn more about Africa's ancient vegetation is on the increase, say Jacobs and her co-authors. That should start to fill gaps in understanding, including the mystery of Africa's palms.

While palm trees are common in wet tropical forests worldwide, that's not the case in Africa today. Palm trees have not been found in abundance in Africa for the past 24 million years, regardless of whether the regional vegetation was forest, say the authors. Oddly, though, abundant palm samples have been found in some African locations dating between 65 million and 25 million years ago, including at Chilga in Ethiopia by Jacobs and Pan.

The implications of that difference are significant for the various endemic mammals of that time, many of which were absent by 23 million years ago, say the authors.

"We are fortunate that the sampling scale of most fossil localities is at the plant community level, and larger-scale changes took place one community at a time," they write. "Thus, as Africa becomes better sampled, the uneven record will ultimately become a more complete narrative of dynamic change at the community and ecosystem levels."

esciencenews.com

Britain's 'earliest hospital' discovered

2010-10-21T17:52:00.002+02:00

Radio carbon analysis of site in Winchester provides date range of AD 960-1030 – preceding Norman conquest.

Archaeologists have uncovered a site that may house Britain's earliest known hospital. Radio carbon analysis at the former Leper Hospital at St Mary Magdalen in Winchester, Hampshire, has provided a date range of AD 960-1030 for a series of burials, many exhibiting evidence of leprosy.

A number of other artefacts, pits, and postholes relate to the same time, including what appears to be a large sunken structure underneath a medieval infirmary.

Most historians and archaeologists had believed hospitals in Britain only dated from after the Norman conquest of 1066.

"This is an important archaeological development," said Dr Simon Roffey from the University of Winchester, which conducted the dig.

"Historically, it has always been assumed that hospitals were a post-conquest phenomenon, the majority founded from the late 11th century onwards.

"However, our excavations have revealed a range of buildings and, more significantly, convincing evidence for a foundation in the 10th century.

"Our excavations at St Mary Magdalen offer an intriguing insight into a little known aspect of the history of both Winchester and England. It is undoubtedly a site of national importance."

Among the earliest known hospitals in the UK is Harbledown in Canterbury, founded by Lanfranc in the 1070s, following the Norman conquest.

Professor Nicholas Orme, a leading researcher on medieval hospitals, added: "I have only studied the documentary evidence but I could not find any such evidence for a hospital before 1066 except perhaps as an activity within a monastery or minster.

"A late Anglo-Saxon hospital would surely be a first for archaeology and indeed for history."

Winchester was the capital of England throughout a large part of the Anglo-Saxon period and after the Norman conquest. The capital was moved to London from the Hampshire city in the 12th century.

guardian.co.uk

Swiss unearth 5,000-year-old door

2010-10-20T18:56:00.001+02:00

Archeologists find 'remarkable' Neolithic wooden door as old as Stonehenge at site of planned car park in Zurich.

Archaeologists in Zurich have unearthed a 5,000-year-old door that may be one of the oldest ever found in Europe.

The ancient poplar wood door is "solid and elegant" with well-preserved hinges and a "remarkable" design for holding the boards together, archaeologist Niels Bleicher said today.

Using tree rings to determine its age, Bleicher believes the door could have been made in 3,063BC, just as construction on Stonehenge began.

"The door is very remarkable because of the way the planks were held together," he told the Associated Press.

Harsh climatic conditions at the time meant people had to build solid houses that would keep out much of the cold wind that blew across Lake Zurich, and the door would have helped, Bleicher said. "It's a clever design that even looks good."

The door was part of a settlement of so-called "stilt houses" frequently found near lakes about a thousand years after agriculture and animal husbandry were first introduced to the pre-Alpine region.

It is similar to a door found in nearby Pfaeffikon, while a third – made from one solid piece of wood – is believed to be even older, possibly 3,700BC, said Bleicher.

The latest door was found at the dig for what is intended to be a new underground car park for Zurich's opera house.

Archaeologists have found traces of at least five Neolithic villages believed to have existed at the site between 3,700 and 2,500 years BC, including objects such as a flint dagger from what is now Italy and an elaborate hunting bow.

guardian.co.uk

New bony-skulled dinosaur species discovered in Texas

2010-04-20T09:07:00.002+02:00

Paleontologists have discovered a new species of dinosaur with a softball-sized lump of solid bone on top of its skull, according to a paper published in the April issue of the journal Cretaceous Research. The species was a plant-eating dinosaur about as big as a medium-sized dog that lived 70 to 80 million years ago, said Nicholas Longrich of Yale University, lead author of the paper. The team discovered two skull fragments in Big Bend National Park in southwest Texas in 2008. They compared them to dozens of fossils from related species found in Canada and Montana before confirming that the fossils represented a new genus of pachycephalosaur, a group of bipedal, thick-skulled dinosaurs.

The researchers named the new species Texacephale langstoni. ("Texacephale" means "Texas head" and "langstoni" is in honor of Wann Langston, a fellow paleontologist.) The new species is one of about a dozen known to have solid lumps of bone on top of their skulls, which Longrich speculates was probably used to ram one another head-on in a manner similar to modern-day musk oxen and cape buffalo.

The discovery of the new species lends further weight to the idea, which has gained popularity in recent years, that dinosaurs found in Canada and the northern United States were distinct from their southern neighbors.

"Instead of roaming across the North American continent, we see pockets of different dinosaurs that are pretty isolated from one another," Longrich said. "Every time we get good fossils from Texas, they end up looking very different from those to the north."

Because fossils from the Big Bend region are rare and tend to be poorly preserved, scientists do not have a complete picture of the different species that once inhabited the area, Longrich said.

But the team may have uncovered an important piece of the puzzle with their discovery. They found that this particular group of dinosaurs, which was previously thought to have originated in Asia, likely evolved in North America.

Longrich expects more related species to be discovered in the future as fossils from the Texas site and elsewhere continue to be examined.

"I think we underestimate how many different species there were," he says.

Yale University

Stalagmite reveals carbon footprint of early Native Americans

2010-04-16T08:48:00.002+02:00

A new study led by Ohio University scientists suggests that early Native Americans left a bigger carbon footprint than previously thought, providing more evidence that humans impacted global climate long before the modern industrial era. Chemical analysis of a stalagmite found in the mountainous Buckeye Creek basin of West Virginia suggests that native people contributed a significant level of greenhouse gases to the atmosphere through land use practices. The early Native Americans burned trees to actively manage the forests to yield the nuts and fruit that were a large part of their diets.

"They had achieved a pretty sophisticated level of living that I don't think people have fully appreciated," said Gregory Springer, an associate professor of geological sciences at Ohio University and lead author of the study, which was published a recent issue of the journal The Holocene. "They were very advanced, and they knew how to get the most out of the forests and landscapes they lived in. This was all across North America, not just a few locations."

Initially, Springer and research collaborators from University of Texas at Arlington and University of Minnesota were studying historic drought cycles in North America using carbon isotopes in stalagmites. To their surprise, the carbon record contained evidence of a major change in the local ecosystem beginning at 100 B.C. This intrigued the team because an archeological excavation in a nearby cave had yielded evidence of a Native American community there 2,000 years ago.

Springer recruited two Ohio University graduate students to examine stream sediments, and with the help of Harold Rowe of University of Texas at Arlington, the team found very high levels of charcoal beginning 2,000 years ago, as well as a carbon isotope history similar to the stalagmite.

This evidence suggests that Native Americans significantly altered the local ecosystem by clearing and burning forests, probably to make fields and enhance the growth of nut trees, Springer said. This picture conflicts with the popular notion that early Native Americans had little impact on North American landscapes. They were better land stewards than the European colonialists who followed, he said, but they apparently cleared more land and burned more forest than previously thought.

"Long before we were burning fossil fuels, we were already pumping greenhouse gasses into the atmosphere. It wasn't at the same level as today, but it sets the stage," Springer said.

This long-ago land clearing would have impacted global climate, Springer added. Ongoing clearing and burning of the Amazon rainforest, for example, is one of the world's largest sources of greenhouse gas emissions. Prehistoric burning by Native Americans was less intense, but a non-trivial source of greenhouse gases to the atmosphere, he said.

Ohio University

The new T. rex: A leech with an affinity for noses

2010-04-15T18:09:00.001+02:00

The new T. rex has ferociously large teeth lining a single jaw. But its length is less than 2 inches. Tyrannobdella rex, which means tyrant leech king, is a new species of blood sucker that lives in the remote parts of the Upper Amazon. Although its regular host remains unknown, it was discovered three years ago in Perú when a 44.5 millimeter leech was plucked from the nose of a girl who had recently been bathing in a river. The new species, described in PLoS ONE, has led to revising the group of leeches that has a habit of feeding from body orifices of mammals. "Because of our analysis of morphology and DNA, we think that Tyrannobdella rex is most closely related to another leech that gets into the mouths of livestock in Mexico," says Anna Phillips, a graduate student affiliated with the American Museum of Natural History and the first author of the paper. "We think the leech could feed on aquatic mammals, from their noses and mouths for example, where they could stay for weeks at a time."

Discoveries of new leech species are not uncommon occurrences. Although there are 600 to 700 species of described leeches, it is thought that there could be as many as10,000 species throughout the world in marine, terrestrial and fresh water environments. Tyrannobdella rex was first brought to the attention of Mark Siddall, curator in the Division of Invertebrate Zoology at the Museum, when he received a specimen collected by Dr. Renzo Arauco-Brown, a Peruvian medical doctor from the School of Medicine at the Universidad Peruana Cayetano Heredia in Lima who was working at a clinic in Chanchamayo province. Siddall immediately recognized it as a new species. His student Alejandro Oceguera-Figueroa described its weird morphology—a single jaw with eight very large teeth, and extremely small genitalia. Two earlier cases from 1997 were re-discovered from different clinics in the western Amazon, one from Lamas province and the other from Yochegua province.

The new genus and species, Tyrannobdella rex, has led to a revision of the phylogenetic relationships among several leech families. Both morphological and genetic data show that this species is most closely related to Pintobdella chiapasensis, a leech from Chiapas that is typically hosted by tapir but also infests cows. Part of the research for this paper involved a Mexican expedition by Phillips and Oceguera-Figueroa to gather new specimens for DNA analysis. Close by on the phylogenetic tree, this group is related to leeches found in India and Taiwan like Dinobdella ferox, the terrible, ferocious leech that is well-known for feeding on mucus membranes and getting into various human orifices. All of these species, and others from Mexico, Africa, and the Middle East, make up the family Praobdellidae, a group of leeches that seems to share this feeding behavior and which can pose a risk to human health in certain parts of the world.

The evolutionary relationship among leeches that currently inhabit distant regions suggests that the common ancestor of this group must have lived when the continents were pressed together into a single land mass, before Pangaea broke up.

"We named it Tyrannobdella rex because of its enormous teeth. Besides, the earliest species in this family of these leeches no-doubt shared an environment with dinosaurs about 200 million years ago when some ancestor of our T. rex may have been up that other T. rex's nose," says Siddall. "The new T. rex joins four other species that use this abbreviated name, including two Miocene fossils (a snail and a scarab beetle), a living Malaysian formicid ant, and, of course, the infamous Cretaceous theropod dinosaur that was described in 1905 by an earlier curator of the American Museum of Natural History."

American Museum of Natural History

300 million year old ancestor revealed in new 3-D model

2010-04-14T10:29:00.004+02:00

An early ancestor of the cockroach that lived around 300 million years ago is unveiled in unprecedented detail in a new three-dimensional 'virtual fossil' model, in research published today in the journal Biology Letters.

Scientists at Imperial College London have made a comprehensive 3D model of a fossilised specimen called Archimylacris eggintoni, which is an ancient ancestor of modern cockroaches, mantises and termites. This insect scuttled around on Earth during the Carboniferous period 359 - 299 million years ago, which was a time when life had recently emerged from the oceans to live on land.

The study reveals for the first time how Archimylacris eggintoni's physical traits helped it to thrive on the floor of Earth's early forests. The fossils of these creatures are normally between 2cm and 9cm in length and approximately 4cm in width.

The lead author of the study, Mr Russell Garwood, a PhD student from the Department of Earth Science and Engineering at Imperial College London, says, "The Carboniferous period is sometimes referred to as the age of the cockroach because fossils of Archimylacris eggintoni and its relatives are amongst the most common insects from this time period. They are found all over the world. People joke about it being impossible to kill cockroaches and our 3D model almost brings this one back to life. Thanks to our 3D modelling process, we can see how Archimylacris eggintoni's limbs were well adapted for all terrains, as it was not only adept in the air but also very agile on the ground."

sciencecodex.com

Egyptians Discover Roman-Era Mummy

2010-04-13T15:27:00.001+02:00

Egyptian archaeologists discovered an intricately carved plaster sarcophagus portraying a wide-eyed woman dressed in a tunic in a newly uncovered complex of tombs at a remote desert oasis, Egypt's antiquities department announced Monday.

It is the first Roman-style mummy found in Bahariya Oasis some 186 miles (300 kilometers) southwest of Cairo, said archaeologist Mahmoud Afifi, who led the dig. The find was part of a cemetery dating back to the Greco-Roman period containing 14 tombs.

"It is a unique find," he told The Associated Press, confirming that initial examinations indicate a mummy is inside the coffin.

The carved plaster sarcophagus is only 3 feet (1 meter) long and shows a woman wearing a long tunic, a headscarf, bracelet and shoes, as well as a beaded necklace. Colored stones in the sarcophagus' eyes gave the appearance she is awake.

Afifi said they had not dated the new find yet, but the burial style indicated she belonged to Egypt's long period of Roman rule lasting a few hundred years and starting 31 B.C.

He said his team first thought they had stumbled across a child's tomb because of its diminutive stature, but the decorations and features indicated it was a woman.

Afifi said it was still unclear who the woman was but said it was most likely she was a wealthy and influential member of her society, judging by the effort taken on the sarcophagus.

Mummies of people of diminutive stature have been unearthed in other parts of Egypt, where they appeared to have importance in local religions at the time, he added.

The archaeologists also found a gold relief showing the four sons of the Egyptian god Horus, other plaster masks of women's faces, several glass and clay utensils and some metal coins.

The metal coins are being checked to see whether they can date the era of the tomb more precisely.

Larger Tomb Complex

Afifi said the find suggested the presence of a larger tomb complex, but said humid weather in the area may have destroyed similar sites.

He said none of the other 13 graves were as complete as that of the woman.

The find was made after archaeologists had made a series of exploratory digs ahead of a local council plan to build a youth center on the land. The area is known for its relics from the Greco-Roman period.

Bahariya Oasis rocketed to fame a decade ago with the discovery of the "Valley of the Golden Mummies," a vast cemetery that has yielded up hundreds of mummies, many covered in gold leaf, from the Greco-Roman period.

Those sarcophagi were decorated in a more traditional ancient Egyptian style, rather than the Roman style of the current find.

The discoveries from this period indicate the comparative wealth and prosperity of the oases at the time due to their location on major desert trading routes.

cbsnews.com

Ancient city yielding new clues in Michoacan, Mexico

2010-04-13T15:24:00.002+02:00

Colorado researchers have discovered and partially mapped a major urban center once occupied by the Purépecha of Mexico, a little-known people who fought the Aztecs to a standstill and who controlled much of western Mexico until diseases brought by the Spanish decimated them.

The "proto-urban center," which researchers have not yet named, sat on volcanic rock on the shores of Lake Pátzcuaro in the central Mexican state of Michoacan, now a tourist destination. It supported as many as 40,000 people until the consolidation of the Purépecha empire about AD 1350 led most of its inhabitants to relocate to the new capital of Tzintzuntzan, six miles away.

"What's really interesting about the site is that it gives us a window into the pre-state period when social complexity was increasing and people were congregating together and starting to modify the landscape," said archaeologist Christopher Fisher of Colorado State University, who will present the findings this week at a St. Louis meeting of the Society for American Archaeology.

Finding that the urban center's population fell as the capital, Tzintzuntzan, grew will also help rewrite the history of the Purépecha, who were also known as Tarascans, said archaeologist Gary Feinman of Chicago's Field Museum, who was not involved in the research.

It indicates, he said, that concentration of the population -- rather than population growth as had previously been believed -- "was a critical element in the concentration of power, particularly in Mesoamerica, where you did not have domesticated animals. People were absolutely critical for moving goods, constructing things and producing food."

Despite the fact that the Purépecha empire was as large and powerful as that of the Aztecs, they "have gotten the short end of the stick as far as public attention goes," Fisher said.

Much of what we know about the Aztecs comes from the colonial records of the Spanish expeditionary force, he noted, but the Spaniards -- who encountered the Aztecs first -- had little contact with the Purépecha until the civilization was already doomed by disease.

Yet the Purépecha not only controlled most of western Mexico, but had a strongly fortified border with the Aztec empire and ultimately defeated the Aztec army in a fierce battle in the late 15th century.

Part of their strength came from their skill as coppersmiths and, despite the fact that they were fierce enemies, the Aztecs traded extensively with them to acquire copper tools, bells and other valuable objects.

Fisher and his team discovered the site last summer as part of their ongoing survey of the Lake Pátzcuaro basin.

Because the lake level has been dropping, the Purépecha site now sits a couple of miles east of the lake -- Fisher is vague about the precise location because of fears of looting -- but at its height was probably no more than a quarter mile from the shore.

The site sits on a landform called malpais, a young, rugged volcanic landscape "that looks like gravel dumped into a big pile," he said.

Because the land is not suitable for agriculture, the foundations of structures have been largely preserved.

The site encompasses about 5 square kilometers (about 1,200 acres). Using rugged computers and specialized GPS receivers, the team has carefully mapped about a fifth of the site, recording more than 1,300 features, including house mounds, room blocks, buildings, small temples, plazas and agricultural terraces.

Such detailed mapping "is quite revolutionary because it gives us a chance to see what the economic picture was, and the social differentiation," said archaeologist Barbara Stark of Arizona State University, who was not involved in the research. "It's hard to describe how important that is for our understanding of these societies."

Most of the site dates from AD 1000 to about 1350, when it began to shrink as the population moved elsewhere. By 1500, it was largely abandoned.

Most of the rest of the empire disappeared soon after. Smallpox and other diseases that were spread to the Aztecs by the Spanish were transmitted to the Purépecha as well, killing 80% to 90% of the population. By the time the Spanish attacked the Purépecha, there was hardly anyone left to resist.

latimes.com

Human fossil discovery -- evidence of new Homo species

2010-04-12T09:47:00.001+02:00

Two partial skeletons have been discovered in the cave deposits in the Cradle of Humankind World Heritage Site near Johannesburg, in the Republic of South Africa by members of the University of the Witwatersrand, Johannesburg. The human fossils, close to 2 million years old, have been classified as a new species: Australopithecus sediba. Australopithecus means "southern ape" and Sediba, taken from the local South African language seSotho means "natural spring, fountain or wellspring".

The findings represent some of the most significant scientific discoveries of recent years and were published today in the scientific journal Science.

Dr Robyn Pickering of the School of Earth Sciences at the University of Melbourne who was one a team of international and Australian scientists to accurately date the sediments surrounding the fossils says, "We are now able to fill in the gap of what happened 2 million years ago in the beginnings of our species."

"It has never been clear where our own genus Homo came from – this new discovery, Australopithecus sediba could answer these questions," she says.

Researchers say this species appears to be a transitional form, maybe the best yet found, between early australopithecines and early members of the genus Homo, thereby replacing other candidates such as Homo habilis (the tool making 'handy' man from east Africa) as the distant ancestor of Homo sapien.

The Sediba fossils are exceptionally well preserved, and therefore provide a unique insight in the period when the earliest members of our genus evolved.

Sediments from surrounding and supporting the fossils were analysed by several research teams.

Using a state-of-the-art uranium lead dating technique, conducted independently and in parallel by Dr Pickering at the University of Melbourne and her former PhD supervisor Professor Jan Kramers from the University of Bern in Switzerland, they produced an identical age result confirming the sediment was close to 2 million years old.

"Together with palaeomagnetic dating of the sediments more closely surrounding the fossils by Andy Herries of UNSW and our team of colleagues led by Professor Paul Dirks from the University of Townsville, we were collectively able to provide an age of 1.95-1.78 million years for the fossils," Dr Pickering says.

"This is the first time, in relation to these renowned caves in South Africa, that we have been able to achieve such high-quality age control."

"Knowing how old these early human (hominin) fossils are, is critical to our knowledge of where this newly found species fits into our family tree," she says.

Associate Professor Jon Woodhead, who heads the Isotope Geosciences laboratory in the School of Earth Sciences at the University of Melbourne, noted "This is a highly significant find and I congratulate Robyn and her colleagues on their discovery."

"Only very recently have we been able to develop the technologies required to allow precise dating of cave sediments such as those found in intimate association with these new fossils."

"This really is the beginning of a 'new era' as such methods have much to contribute to studies of global climate change, biodiversity and, in this case, human evolution."

"The University of Melbourne is a world leader in this area and we are proud to have been able to contribute to this important discovery."

University of Melbourne

Stone Age Scandinavians unable to digest milk

2010-04-06T11:15:00.000+02:00

The hunter-gatherers who inhabited the southern coast of Scandinavia 4,000 years ago were lactose intolerant. This has been shown by a new study carried out by researchers at Uppsala University and Stockholm University. The study, which has been published in the journal BMC Evolutionary Biology, supports the researchers' earlier conclusion that today's Scandinavians are not descended from the Stone Age people in question but from a group that arrived later. "This group of hunter-gatherers differed significantly from modern Swedes in terms of the DNA sequence that we generally associate with a capacity to digest lactose into adulthood," says Anna Linderholm, formerly of the Archaeological Research Laboratory, Stockholm University, presently at University College Cork, Ireland.

According to the researchers, two possible explanations exist for the DNA differences.

"One possibility is that these differences are evidence of a powerful selection process, through which the Stone Age hunter-gatherers' genes were lost due to some significant advantage associated with the capacity to digest milk," says Anna Linderholm. "The other possibility is that we simply are not descended from this group of Stone Age people."

The capacity to consume unprocessed milk into adulthood is regarded as having been of great significance for human prehistory.

"This capacity is closely associated with the transition from hunter-gatherer to agricultural societies," says Anders Götherström of the Department of Evolutionary Biology at Uppsala University.

He serves as coordinator of LeCHE (Lactase persistence and the early Cultural History of Europe), an EU-funded research project focusing on the significance of milk for European prehistory.

"In the present case, we are inclined to believe that the findings are indicative of what we call "gene flow," in other words, migration to the region at some later time of some new group of people, with whom we are genetically similar," he says. "This accords with the results of previous studies."

The researchers' current work involves investigating the genetic makeup of the earliest agriculturalists in Scandinavia, with an eye to potential answers to questions about our ancestors.

Uppsala University

An archaeological mystery in a half-ton lead coffin

2010-04-01T09:09:00.002+02:00

In the ruins of a city that was once Rome's neighbor, archaeologists last summer found a 1,000-pound lead coffin. Who or what is inside is still a mystery, said Nicola Terrenato, the University of Michigan professor of classical studies who leads the project---the largest American dig in Italy in the past 50 years.

The sarcophagus will soon be transported to the American Academy in Rome, where engineers will use heating techniques and tiny cameras in an effort to gain insights about the contents without breaking the coffin itself.

"We're very excited about this find," Terrenato said. "Romans as a rule were not buried in coffins to begin with and when they did use coffins, they were mostly wooden. There are only a handful of other examples from Italy of lead coffins from this age---the second, third or fourth century A.D. We know of virtually no others in this region."

This one is especially unusual because of its size.

"It's a sheet of lead folded onto itself an inch thick," he said. "A thousand pounds of metal is an enormous amount of wealth in this era. To waste so much of it in a burial is pretty unusual."

Was the deceased a soldier? A gladiator? A bishop? All are possibilities, some more remote than others, Terrenato said. Researchers will do their best to examine the bones and any "grave goods" or Christian symbols inside the container in an effort to make a determination.

"It's hard to predict what's inside, because it's the only example of its kind in the area," Terrenato said. "I'm trying to keep my hopes within reason."

Human remains encased in lead coffins tend to be well preserved, if difficult to get to. Researchers want to avoid breaking into the coffin. The amount of force necessary to break through the lead would likely damage the contents. Instead, they will first use thermography and endoscopy. Thermography involves heating the coffin by a few degrees and monitoring the thermal response. Bones and any artifacts buried with them would have different thermal responses, Terrenato said. Endoscopy involves inserting a small camera into the coffin. But how well that works depends on how much dirt has found its way into the container over the centuries.

If these approaches fail, the researchers could turn to an MRI scan---an expensive option that would involve hauling the half-ton casket to a hospital.

The dig that unearthed this find started in summer 2009 and continues through 2013. Each year, around 75 researchers from around the nation and world, including a dozen U-M undergraduate students, spend two months on the project at the ancient city of Gabii (pronounced "gabby").

The site of Gabii, situated on undeveloped land 11 miles east of Rome in modern-day Lazio, was a major city that pre-dates Rome but seems to have waned as the Roman Empire grew.

Studying Gabii gives researchers a glimpse into pre-Roman life and offers clues to how early Italian cities formed. It also allows them broader access to more substantial archaeological layers or strata. In Rome, layers of civilization were built on top of each other, and archaeologists are not able or allowed to disturb them.

"In Rome, so often, there's something in the way, so we have to get lucky," Terrenato said. "In Gabii, they should all be lucky spots because there's nothing in the way."

Indeed, Terrenato and others were surprised to find something as significant as this coffin so soon.

"The finding of the lead coffin was exhilarating," said Allison Zarbo, a senior art history major who graduates this spring.

Zarbo didn't mind that after the researchers dug up the coffin once, they had to pile the dirt back on to hide it from looters overnight.

"The fact that we had to fill the hole was not so much of a burden as a relief!" Zarbo said. "For academia to lose priceless artifacts that have been found fully in context would be very damaging to our potential knowledge."

Students spent most of their time pick-axing, shoveling, and manning the wheelbarrows, said Bailey Benson, a junior who is double majoring in classical archaeology and art history.

"By the end of the day, not even a 20-minute shower can remove all the dirt and grime you get covered in," Benson said. "It's hard but satisfying work. How many people can say they uncovered an ancient burial?"

University of Michigan

Ancient snakes living on Madagascar

2010-03-31T10:32:00.002+02:00

"Blindsnakes are not very pretty, are rarely noticed, and are often mistaken for earthworms," admits Blair Hedges, professor of biology at Penn State University. "Nonetheless, they tell a very interesting evolutionary story." Hedges and Nicolas Vidal, of the Muséum National d'Histoire Naturelle in Paris, are co-leaders of the team that discovered that blindsnakes are one of the few groups of organisms that inhabited Madagascar when it broke from India about 100 million years ago and are still living today. The results of their study will be published in the 31 March 2010 issue of the Royal Society journal Biology Letters. Blindsnakes comprise about 260 different species and form the largest group of the world's worm-like snakes -- scolecophidians. These burrowing animals typically are found in southern continents and tropical islands, but occur on all continents except Antarctica. They have reduced vision -- which is why they are called "blind" -- and they feed on social insects including termites and ants. Because there are almost no known fossil blindsnakes, their evolution has been difficult to piece together. Also, because of their underground lifestyle, scientists have long wondered how they managed to spread from continent to continent.

In this study, the team investigated the evolution of blindsnakes by examining the genetics of living species. They extracted five nuclear genes, which code for proteins, from 96 different species of worm-like snakes to reconstruct the branching pattern of their evolution and allow the team to estimate the times of divergence of different lineages within blindsnakes using molecular clocks. "Our findings show that continental drift had a huge impact on blindsnake evolution," explains Vidal, "by separating populations from each other as continents moved apart."

Mutations in the genes record the history of these blurry-eyed serpents. The genetic research reveals that the original stock of worm-like snakes arose on Gondwana, the ancient southern supercontinent. The initial split occurred about 155 million years ago as Gondwana divided into East Gondwana (the landmasses of Antarctica, India, Madagascar, and Australia) and West Gondwana (the landmasses of South America and Africa). The residents of East Gondwana -- the blindsnakes -- then diverged into several lineages including a new family named in this study and found only on Madagascar. Later, East Gondwana further divided into a new paleolandmass -- called by the researchers "Indigascar" (India plus Madagascar) -- and another comprised of Australia and Antarctica. The research suggests that the new family on Madagascar arose as a result of the break-up of the Indigascar landmass about 94 million years ago.

Madagascar's long isolation has led to the evolution of many unique endemic animals including this family of blindsnakes, various lemurs, and other rare mammals. Unfortunately, both the animals and plants of Madagascar are now endangered by habitat loss. Says team member Miguel Vences, a professor at the Technical University of Braunschweig, Germany, and authority on the biodiversity of Madagascar, "Finding such ancient roots for a group of animals in Madagascar gives us even more reason to protect their rapidly declining habitat."

If blindsnakes got their start on Indigascar, leaving an endemic living family as evidence on Madagascar, how did they get to all of those other places in the world that they occupy today -- Europe, Asia, Australia, Africa, and the Americas?

The phylogeny constructed by the Hedges and Vidal team shows a series of diversifications within the blindsnakes, outside of Madagascar, that occurred between 63 and 59 million years ago. The period of greatest diversification coincided with a time of low sea levels, when connections between continents were forming and the dispersal of such unlikely animals by floating on flotsam was easier. Blindsnakes must have moved either out of Africa via Europe and Asia -- the ancient northern supercontinent Laurasia -- or out of India and then from southeast Asia to Australia at about 28 million years ago. Since there were no land connections between Asia and Australia at this time, these blindsnakes could have reached Australia only by crossing the ocean on floating flotsam. After that point, the splits within the blindsnakes probably occurred because they were following the evolution and spread of their prey -- ants and termites -- in various geographic regions.

Floating across oceans seems an unlikely mechanism for a burrowing animal to spread to new continents, but there is a second instance of ocean crossing by blindsnakes among the groups left on West Gondwana: West Gondwana broke up about 100 million years ago, making Africa and South America separate continents, but the genetic split between African and South American blindsnakes occurred only at about 63 million years ago. This finding shows that blindsnakes probably were confined to Africa when West Gondwana broke up and only later traveled to South America -- and still later to the West Indies -- by floating across the Atlantic from east to west.

This journey has rarely been documented. Only six or seven other vertebrates are thought to have crossed the Atlantic in a westward direction. However, the crossing would have taken no more than six months and might not have been too difficult for blindsnakes, which have a relatively low need for food and may have been floating on vegetation rafts along with their insect prey.

"Some scientists have argued that oceanic dispersal is an unlikely way for burrowing organisms to become distributed around the world," observes Hedges. "Our data now reinforce the message that such 'unlikely' events nonetheless happened in evolutionary history."

Penn State

Ancient doorway to afterlife discovered in Egypt

2010-03-30T09:56:00.001+02:00

A large red granite false door from the tomb of an ancient queen's powerful vizier has been discovered in Luxor, Egypt's culture minister said on Monday.

The carved stone door -- which ancient Egyptians believed was the threshold to the afterlife -- was unearthed near the Karnak Temple in Luxor and belongs to the tomb of User, a powerful advisor to the 18th dynasty Queen Hatshepsut, Faruk Hosni said in a statement.

The door, 1.75 metres (5.7 feet) high and 50 cm (19 inches) thick, is engraved with religious texts and various titles used by User, including mayor of the city, vizier and prince, antiquities chief Zahi Hawass was quoted as saying.

"The newly discovered door was reused during the Roman period. It was removed from the tomb of User and used in the wall of a Roman structure," said Mansur Boraik, who headed the excavation mission.

Hatshepsut, who ruled Egypt between 1479 BC and 1458 BC, was the longest reigning female pharaoh.

QMI

Scientists find first ever southern tyrannosaur dinosaur

2010-03-29T09:58:00.001+02:00

Scientists from Cambridge, London and Melbourne have found the first ever evidence that tyrannosaur dinosaurs existed in the southern continents. They identified a hip bone found at Dinosaur Cove in Victoria, Australia as belonging to an ancestor of Tyrannosaurus rex. The find sheds new light on the evolutionary history of this group of dinosaurs. It also raises the crucial question of why it was only in the north that tyrannosaurs evolved into the giant predators like T. rex.

The 30cm-long pubis bone from Dinosaur Cove looks like a rod with two expanded ends, one of which is flattened and connects to the hip and the other looks like a 'boot'.

According to Dr Roger Benson of the Department of Earth Sciences at the University of Cambridge, who identified the find: "The bone is unambiguously identifiable as a tyrannosaur because these dinosaurs have very distinctive hip bones."

The discovery lays to rest the belief held by some scientists that tyrannosaurs never made it to the southern continents.

"This is an exciting discovery because tyrannosaur fossils had only ever been found in the northern hemisphere before and some scientists thought tyrannosaurs never made it down south.

"Although we only have one bone, it shows that 110 million years ago small tyrannosaurs like ours might have been found worldwide. This find has major significance for our knowledge of how this group of dinosaurs evolved." says Dr Benson.

Dr Paul Barrett, Palaeontologist at the Natural History Museum, London and member of the research team commented: "The absence of tyrannosauroids from the southern continents was becoming more and more anomalous as representatives of other 'northern' dinosaur groups started to show up in the south. This find shows that tyrannosauroids were able to reach these areas early in their evolutionary history and also hints at the possibility that others remain to be discovered in Africa, South America and India."

The bone would have come from an animal about three metres long and weighing around 80 kg, similar to a human, and would have had the large head and small arms that make tyrannosaurs so distinctive.

The newly identified dinosaur, known as NMV P186069, was much smaller than T. rex, which was 12 metres long and weighed around four tonnes. Giant size like this only evolved late in the tyrannosaur lineage.

Compared with T. rex, which lived about 70 million years ago at the end of Cretaceous period, NMV P186069 lived earlier during the Cretaceous, around 110 million years ago.

During the time of the dinosaurs the continents gradually went from a single supercontinent towards something like their present-day arrangement. This tyrannosaur is from the mid-stages of this continental break-up, when the southern continents of South America, Antarctica, Africa and Australia had separated from the northern continents, but had not separated from each other.

While answering the question of whether or not tyrannosaurs lived in both the southern and northern hemispheres, the new find leaves another, deeper mystery: why did tyrannosaurs evolve into giant predators such as T. rex only in the northern hemisphere?

According to Dr Benson: "It is difficult to explain why different groups succeeded in the north and the south if they originally existed in both places. What we need to know now is just how diverse the early radiation of tyrannosaurs was, why they went extinct, leaving only giant-sized, short-armed species like T. rex, and how successful they might have been in the southern hemisphere. We can only answer these questions with new discoveries."

The paper is published today in Science.

University of Cambridge

A new fossil species found in Spain

2010-03-26T07:20:00.002+01:00

In the '80s, Spanish researchers found the first fossils of Cloudina in Spain, a small fossil of tubular appearance and one of the first animals that developed an external skeleton between 550 and 543 million years ago. Now palaeontologists from the University of Extremadura have discovered a new species, Cloudina carinata, the fossil of which has preserved its tridimensional shape. "Cloudina carinata is characterised by its elaborate ornamentation and complexity of the shells and tube that are formed when inserted", Iván Cortijo, main author and researcher in the Area of Palaeontology at the University of Extremadura, describes to SINC.

The study, which was recently published in Precambrian Research, describes various specimens of the new species. These fossils show evidence of asexual reproduction, until now "only described in Chinese specimens of Cloudina", and are "one of the oldest examples of reproduction in animals in the fossil register", maintains the researcher from Extremadura.

The fossils have been found in the archaeological site El Membrillar (Badajoz), one of the few sites in Europe where remains of Cloudina can be found. "The specimens display exceptional preservation, they appear preserved in three dimensions, and show their original form and numerous details of the shells", Cortijo points out.

The discovery of new species of Cloudina is important "for understanding the early evolution of animals", states Cortijo, who adds that "its importance for understanding the origin of skeletons is indisputable". Despite the fact that its relation to other groups of animals is uncertain, Cloudina has been compared to cnidaria (medusas and corals) and annelida (polychaeta sea worms, earthworms and leeches).

According to the research team, the study of fossils from the Ediacaran period (between 630 and 540 million years ago) and of other fossils from the early Cambrian (540 million years ago) reveals the path followed by evolution at a crucial moment in the history of life, when the first animals appeared. This first evolutionary radiation of animals reached its apex in the so-called "great Cambrian explosion" or "Big-Bang of evolution".

In search of Cloudina

In the '70s specimens of Cloudina were discovered for the first time in Namibia and later they were discovered in Oman, southern China and the south-east of the USA. According to scientists, it is a fossil indicative of the terminal Ediacaran, which marks the end of the Proterozoic eon, and gives way to the Phanerozoic, when the great radiation of animals began.

In Spain Cloudina was discovered in the '80s thanks to Teodoro Palacios, director of the research group Palaeontology and Stratigraphy of the Neoproterozoic and Palaeozoic at the University of Extremadura.

FECYT - Spanish Foundation for Science and Technology

New ancestor? Scientists ponder DNA from Siberia

2010-03-25T07:23:00.002+01:00

In the latest use of DNA to investigate the story of humankind, scientists have decoded genetic material from an unidentified human ancestor that lived in Siberia and concluded it might be a new member of the human family tree.

The DNA doesn't match modern humans or Neanderthals, two species that lived in that area around the same time — 30,000 to 50,000 years ago.

Instead, it suggests the Siberian species lineage split off from the branch leading to moderns and Neanderthals a million years ago, the researchers calculated. And they said that doesn't seem to match the history of human ancestors previously known from fossils.

So the Siberian species may be brand new, although the scientists cautioned that they're not ready to make that claim yet.

Other experts agreed that while the Siberian species may be new, the case is far from proven.

"We really don't know," said Ian Tattersall of the American Museum of Natural History in New York, who wasn't involved in the new research.

But "the human family tree has got a lot of branchings. It's entirely plausible there are a lot of branches out there we don't know about."

The discovery "is like many new finds," said Eric Delson of Lehman College of the City University of New York, who didn't participate in the new work. "You say, `I think this is different, but I'm not sure.' And then you look for more material and you try to make better comparisons."

The researchers, who say the Siberian species is not a direct ancestor of modern-day people, hope further genetic analysis will show if it's a new species. Some experts are skeptical about whether such analysis will resolve that.

In any case, the finding emphasizes that quite unlike the present day, anatomically modern humans have often lived alongside their evolutionary relatives, one expert said.

"We weren't alone," said Todd Disotell of New York University, who was familiar with the new work. "When we became modern, we didn't instantly replace everybody. There were other guys running around who survived quite well until very, very recently."

Just last month, other researchers used DNA analysis to show the genetic diversity still present in residents of Africa, the cradle of the human race. And another project produced the first genome of an ancient human — a man who lived in Greenland some 4,000 years ago.

The new work, published online Wednesday by the journal Nature, is reported by Johannes Krause and Svante Paabo of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, and others.

They describe mapping DNA from what appeared to be a youngster's pinkie finger bone, which had been recovered in 2008 from Denisova Cave in Altai Mountains of southern Siberia. They showed how it differed from DNA of 54 modern-day people and six Neanderthals.

Their analysis indicated the Siberian species last shared a common ancestor with modern humans and Neanderthals about 1 million years ago. That in turn suggested there was a previously unrecognized migration out of Africa around that time, they said.

The work decoded the complete set of DNA from mitochondria, the power plants of cells. That's different from the better-known DNA that comes from cell nuclei and determines things like eye color. Paabo said the researchers are working to decode nuclear DNA from the Siberian species. That will reveal whether it was closely related to Neanderthals or today's humans, and answer questions like whether it interbred with Neanderthals or ancestors of modern-day people, he said.

Without a completed analysis of the nuclear DNA, "we are not saying this is a new species," Paabo said, although he said that's a likely possibility.

Rick Potts, director of the Smithsonian Institution's Human Origins Program, said the Siberian find might represent Homo heidelbergensis or Homo erectus. And even analysis of the Siberian species' nuclear DNA won't show if it's distinct from those ancestors, he said.

As for the study's suggestion of a migration out of Africa about a million years ago, Potts said there's already evidence of one or two migrations around that time.

The finger bone recovered from the Siberian species is not enough for a fossil-to-fossil comparison with other ancient species to show whether it's a new species, Delson said.

He suspects it might be a descendant of Homo erectus that's already documented in some fossil remains in northern Africa and Europe. Scientists are still trying to figure out how many species of the Homo grouping those bones represent and what name or names to attach to them, he said.

Disotell said the new creature could be an early version of Homo antecessor, a forerunner of Neanderthals and modern humans known from fossils in Spain. Or, he said, it could be a new species. In fact, the eventual decision could hinge mostly on the philosophical question of just how different a creature has to be to be declared a new species, he said.

Potts said that in the new work, "what we're seeing is a really, really interesting distant echo of the DNA history of human evolution.... This is an amazingly powerful technique that these guys have. This is going to be a growth industry in the study of human evolution."

MIA

New dinosaur species found in Utah sandstone

2010-03-24T07:21:00.002+01:00

A new species of dinosaur has emerged from the rocks of southern Utah.

Buried by a collapsing sand dune, perhaps 185 million years ago, the new dino was probably a plant eater and an early relative of the giant animals later known as sauropods, researchers report in Tuesday's edition of the journal PLoS One.

Named Seitaad ruessi, the species was 10-to-15 feet long and 3-to-4 feet high. It's bones were found protruding from sandstone at the base of a cliff, directly below an ancient Anasazi cliff dwelling.

No humans were around at the time of the dinosaurs, but researchers say the bones could well have been visible when the early Indians lived there.

The name Seitaad comes from the word "Seit'aad," which was a sand monster that buried its victims in dunes in Navajo legend, according to the researchers. The newly named skeleton had been swallowed by a sand dune.

So, might visible dinosaur remains have given rise to the ancient Indian monster legend?

"That's a lot of speculation, but anything's possible," said Mark Loewen, a paleontologist at the Utah Museum of Natural History and instructor in the Department of Geology and Geophysics at the University of Utah.

One of the Anasazi dwellings included a stone with a dinosaur footprint in its center, he noted.

The ruessi part of the name is in honor of poet and naturalist Everett Ruess who disappeared in southern Utah in 1934.

Understanding how dinosaurs lived in the past, how their environments changed and affected them, is important for understanding our changing world today, Loewen said.

The nearly complete skeleton is missing only its head, one toe and a lower shinbone, he said, noting erosion over the years probably accounts for the missing parts.

What the researchers have is similar to other sauropodomorphs found in South America and southern Africa, which were all vegetarians, he explained in a telephone interview. However, Seitaad did have a claw on its front limbs, which Loewen suggested was probably used for defense.

"We were absolutely shocked" by the discovery of this dinosaur, Loewen said. It was found in 2004 by a local artist studying rock paintings and the scientists went to the area immediately when they learned of it, he said. The bones were excavated the following year by Museum researchers.

While dinosaur remains have been found in other parts of Utah fossils are rare in the Navajo sandstone areas and generally have been from smaller creatures.

"This new find suggests that there may be more dinosaurs yet to be discovered in these rocks," said Joseph Sertich, co-author of the report and currently a doctoral student at New York's Stony Brook University.

news.yahoo.com

University of Kansas researcher investigates mysterious stone spheres in Costa Rica

2010-03-23T07:22:00.002+01:00

The ancient stone spheres of Costa Rica were made world-famous by the opening sequence of "Raiders of the Lost Ark," when a mockup of one of the mysterious relics nearly crushed Indiana Jones. So perhaps John Hoopes is the closest thing at the University of Kansas to the movie action hero.

Hoopes, associate professor of anthropology and director of the Global Indigenous Nations Studies Program, recently returned from a trip to Costa Rica where he and colleagues evaluated the stone balls for UNESCO, the United Nations cultural organization that might grant the spheres World Heritage Status.

His report will help determine if sites linked to the massive orbs will be designated for preservation and promotion because of their "outstanding value to humanity."

Hoopes, who researches ancient cultures of Central and South America, is one of the world's foremost experts on the Costa Rican spheres. He explained that although the stone spheres are very old, international interest in them is still growing.

"The earliest reports of the stones come from the late 19th century, but they weren't really reported scientifically until the 1930s — so they're a relatively recent discovery," Hoopes said. "They remained unknown until the United Fruit Company began clearing land for banana plantations in southern Costa Rica."

According to Hoopes, around 300 balls are known to exist, with the largest weighing 16 tons and measuring eight feet in diameter. Many of these are clustered in Costa Rica's Diquis Delta region. Some remain pristine in the original places of discovery, but many others have been relocated or damaged due to erosion, fires and vandalism.

The KU researcher said that scientists believe the stones were first created around 600 A.D., with most dating to after 1,000 A.D. but before the Spanish conquest.

"We date the spheres by pottery styles and radiocarbon dates associated with archeological deposits found with the stone spheres," Hoopes said. "One of the problems with this methodology is that it tells you the latest use of the sphere but it doesn't tell you when it was made. These objects can be used for centuries and are still sitting where they are after a thousand years. So it's very difficult to say exactly when they were made."

Speculation and pseudoscience have plagued general understanding of the stone spheres. For instance, publications have claimed that the balls are associated with the "lost" continent of Atlantis. Others have asserted that the balls are navigational aids or relics related to Stonehenge or the massive heads on Easter Island.

"Myths are really based on a lot of very rampant speculation about imaginary ancient civilizations or visits from extraterrestrials," Hoopes said.

In reality, archaeological excavations in the 1940s found the stone balls to be linked with pottery and materials typical of pre-Columbian cultures of southern Costa Rica.

"We really don't know why they were made," Hoopes said. "The people who made them didn't leave any written records. We're left to archeological data to try to reconstruct the context. The culture of the people who made them became extinct shortly after the Spanish conquest. So, there are no myths or legends or other stories that are told by the indigenous people of Costa Rica about why they made these spheres."

Hoopes has a created a popular Web page to knock down some of the misconceptions about the spheres. He said the stones' creation, while vague, certainly had nothing to do with lost cities or space ships.

"We think the main technique that was used was pecking and grinding and hammering with stones," said Hoopes. "There are some spheres that have been found that still have the marks of the blows on them from hammer stones. We think that that's how they were formed, by hammering on big rocks and sculpting them into a spherical shape."

University of Kansas

Students discover new species of raptor dinosaur

2010-03-19T11:12:00.001+01:00

A new species of dinosaur, a relative of the famous Velociraptor, has been discovered in Inner Mongolia by two PhD students. The exceptionally well preserved dinosaur, named Linheraptor exquisitus, is the first near complete skeleton of its kind to be found in the Gobi desert since 1972, and will help scientists work out the appearance of other closely related dinosaur species.

Linheraptor is in the Dromaeosauridae family of the carnivorous theropod dinosaurs and lived during the Late Cretaceous period. In addition to Linheraptor and Velociraptor, theropod dinosaurs include charismatic meat-eaters like Tyrannosaurus rex and modern birds.

The two PhD students, Michael Pittman from UCL (University College London) and Jonah Choiniere from George Washington University (GWU), found the dinosaur sticking out of a cliff face during a field project in Inner Mongolia, China. Their research is published online today in the journal Zootaxa.

"Jonah saw a claw protruding from the cliff face. He carefully removed it and handed it to me. We went through its features silently but he wanted my identification first. I told him it was from a carnivorous dinosaur and when he agreed I'm surprised nobody in London heard us shouting," said Michael Pittman, a PhD student in the UCL Department of Earth Sciences who was the co-discoverer of the dinosaur.

"I've always wanted to discover a dinosaur since I was a kid, and I've never given up on the idea. It was amazing that my first discovery was from a Velociraptor relative. My thesis is on the evolution and biomechanics of dinosaur tails but the carnivorous dinosaurs are my favourite and my specialty," he added.

At approximately 2.5 metres long and 25 kilograms, the researchers believe Linheraptor would have been a fast, agile predator that preyed on small horned dinosaurs related to Triceratops. Like other dromaeosaurids, it possessed a large "killing claw" on the foot, which may have been used to capture prey. Within the Dromaeosauridae family, Linheraptor is most closely related to another recently discovered species Tsaagan mangas.

Linheraptor differs from all other dromaeosaurs because of a triangular hole in front of the eye socket called the antorbital fenestra, which is a space in the skull that sinuses would have occupied. In Linheraptor this triangular hole is divided into two cavities – one of which is particularly big.

"This is a really beautiful fossil and it documents a transitional stage in dromaeosaurid evolution," said Dr. Xu Xing, Professor of Palaeontology at the Institute of Vertebrate Paleontology & Paleoanthropology (IVPP).

Linheraptor was found in rocks of the Wulansuhai Formation, part of a group of red sandstone rocks found in Inner Mongolia, China during a field expedition by the researchers in 2008. It is the fifth dromaeosaurid discovered in these rocks, which are famous for their preservation of uncrushed, complete skeletons.

The research was done as part of the Inner Mongolia Research project, led by Dr. Xu, which aims to better understand the Late Cretaceous ecosystem of Inner Mongolia, China which is analogous but less well-studied than the well known Late Cretaceous ecosytem of Outer Mongolia. The research was funded by the Geological Society of London, the US National Science Foundation, the Chinese National Science Foundation, and George Washington University.

University College London

A blue mystery

2010-03-18T11:00:00.002+01:00

Jennifer Smith, PhD, associate professor of earth and planetary sciences in Arts & Sciences at Washington University in St. Louis, was belly crawling her way to the end of a long, narrow tunnel carved in the rock at a desert oasis by Egyptians who lived in the time of the pharaohs. "I was crawling along when suddenly I felt stabbed in the chest," she says. "I looked down and saw that I was pressing against the broken end of a long bone. That freaked me out because at first I thought I was crawling over bodies, but I looked up and saw a sheep skull not too far away, so I calmed down. At least the bones weren't human."

What was she doing in the tunnel?

The answer: seeking an uncontaminated sample of a mineral that might have been the key ingredient in the blue used to decorate "blue painted pottery" popular among the Egyptian elite during the New Kingdom (1550 to 1079 BCE).

Colleague Colin A. Hope, an expert in blue painted pottery, had asked if she wouldn't help him pin down the source of the blue pigment by sampling and analyzing material fromt he mine.

Hope and Smith, together with Paul Kucera, a doctoral student at Monash University who first identified the mines, describe the pottery, the mines and the mineral in a chapter of Beyond the Horizon, a festschrift for the Egyptologist Barry A. Kemp

'Generic geologist'

In the wastes of the eastern Sahara, nestled against the limestone escarpment that separates the desert from the Nile Valley, lies the Dakhleh Oasis. This fortunate spot, where deep water is able to reach the surface along fractures and faults under its own pressure, has been continuously inhabited for a very long time — perhaps as long as 400,000 years.

During that period there were roughly four glacial cycles and, although Egypt itself was ice-free, the local climate oscillated from hyperarid to semi-arid as the Earth's orbital position drove changes in the location of the tropical rainfall belts.

Smith studies the impact of these climate fluctuations on ancient oasis dwellers.

But Smith is also the "generic geologist" as she puts it, for the Dakhleh Oasis Project, a long-term study of the oasis that covers the entire stretch of Dakhleh history, from the Neolithic through the Pharaonic, Roman, Islamic and modern settlements, and employs — off and on — more than 50 specialists.

"The dig house is open from November until March," Smith says.

As generic geologist, Smith was asked to help with a material-sourcing puzzle that she says was "way outside her period." During the 2007 season, Colin A. Hope, PhD, associate professor and director of the Center for Archaeology and Ancient History at Monash University in Australia, asked her whether a mineral found at the oasis could have been used to color the blue painted pottery.

It was a small question but an intriguing one.

Blue painted pottery

Most Egyptian pottery is undecorated, but during the New Kingdom, the period when Egypt is at the zenith of its power, a variety of pottery was elegantly decorated in a distinctive pale blue.

The pottery has been found at many sites in Egypt, and also in the Middle East and in Sudan.

The largest deposits, however, were found at New Kingdom sites in Egypt, including Malqata (the palace complex of Amenhotep III), Amarna (the remains of the city built by the Akenaten, the famous pharaoh who moved the capital from Thebes and established his own religion), the cemetary at Deir el-Medineh (the village where artisans who worked on the tombs in the Valley of the Kings during the New Kingdom lived), and the Great Temple of Amun (patron of kingship during the New Kingdom).

"Walking over some sites, it is only a matter of minutes before several shards of blue painted pottery or cobalt blue glass or faience can be collected," Hope, who has written extensively about the pottery, says.

Given the restricted use to which the pigment was put and the archeological sites where remnants were found, Hope believes it was probably available only to artisans associated with major royal residences.

The pale blue is distinguishable at a glance from the brilliant blues and blue-greens of the faience glazes common from the 3000 BC onward. Faience, probably most familiar in the form of the small statue of a hippo nicknamed William that is now in the collection of the Metropolitan Museum of Art in New York, was made by adding ground copper to ground quartz to create what ceramists today call Egyptian paste.

But it is difficult to create durable patterns with copper pigment on pottery, says Hope. "Copper-based pigments must be applied in thick layers and were added after firing, so they tended to flake off when an object was handled. Instead of copper, the colorant used on most of the blue painted pottery is cobalt, which was fired onto the pots.

Where did the cobalt-bearing mineral come from? Analysis of the paint showed that the cobalt was accompanied by trace amounts of zinc, nickel and manganese, a mixture of elements distinctive enough to serve as a chemical fingerprint.

The mines of Dakhleh

At the height of its power, the Egyptian administration of the Nile Valley sponsored mineral exploitation of the Valley and surrounding desert regions. As early as 1980, it was suggested that the cobalt might have come from the desert oases at Dakhleh and Kharga.

In the lower foothills of the oasis escarpment at the western end of Dakhleh, four mine shafts were meticulously hand-cut into the rock. Steps carved along the shafts allowed a safe descent. The shafts provided access to horizontal galleries, some as long as 15 meters, that followed horizontal veins of the mineral alum.

A few centimeters thick, the alum veins are fibrous, pale gray to pink in color and slightly astringent.

Alum is both the term for a specific compound and for a class of compounds, all of which contain two negatively charged sulfate groups and two chemical elements or groups bearing a positive charge. The specific compound is hydrated aluminum potassium sulfate but many other elements or groups can substitute for the aluminum and potassium, and cobalt is one of these.

Alum was probably exploited for a variety of purposes in ancient times, some having nothing to do with color. The Egyptians, for example, used alum both to whiten skins during tanning and to prepare cloth to absorb dye.

Alum is still used today in styptic pencils to stem bleeding and in recipes for pickling cucumbers. More recently, it has been in vogue as a "crystal deodorant" that is sold as more natural than older deodorant products.

Was the Dakhleh Oasis alum used as a general-purpose astringent, or did it have the same chemical fingerprint as the blue paint on the pottery?

Analyzing the alum

To find out, Smith needed to sample the alum and analyze its composition.

"I wanted to get relatively unaltered samples," she says, "which is why I was crawling to the end of a gallery. The galleries were small enough you couldn't really crawl on your hand and knees: you had to belly crawl."

Smith brought the samples she collected back to Washington University where she ran them through a variety of sophisticated analytical instruments. "When we characterize a natural mineral," she says, "we want to know two things: its chemical composition and then how the elements that make it up are arranged, or its crystal structure."

In the case of the Dakhleh alum, the crystal structure was of little use because it would have been destroyed in preparing the paint. Only the composition could connect the alum to the pottery.

Smith's results showed that the alum did contain cobalt, although they weren't particularly rich in this element. The cobalt, however, was accompanied by trace amounts of manganese, nickel and zinc, the same mixture of elements found in the blue paint.

Surprised by the low concentration of cobalt, Smith wondered if the ancient artisans hadn't found a way to concentrate it on site. One sample she collected, a crust at the edge of a partially flooded mine shaft, had a higher cobalt content than the others. Because sulphate dissolves easily and the mines were much more likely to have been flooded in the past, she wondered whether the cobalt was mined not by chipping it out of the rock but instead by ladling water out of the mines and collecting the sediment left over when the water evaporated.

"But this is wild arm waving given the amount of data," Smith says.

This small exercise in archeological problem solving left her with a deep respect for the long-vanished miners.

"I look at all these different veins of sulfate and I don't know which are useful for which purposes without doing analyses, but they must have had ways of telling from observable properties which ones to mine. That's impressive," she says.

Washington University in St. Louis

3,400-Year-Old Statues Unearthed in Egypt

2010-03-17T09:08:00.001+01:00

Large Granite Statues Depicting God of Wisdom and Pharaoh Amenhotep III Found at Recently-Discovered Mortuary Temple.

A team of archaeologists unearthed two large red granite statues in southern Egypt at the mortuary temple of one of the most powerful pharaohs, who ruled nearly 3,400 years ago, the Culture Ministry said Tuesday.

A ministry statement said the team discovered a 13-foot statue of Thoth, the ancient god of wisdom, and the top part of a statue of Pharaoh Amenhotep III standing next to another god.

Both were found buried in the pharaoh's mortuary temple on the west bank of the Nile in the southern temple city of Luxor.

On Feb. 28, archaeologists discovered a massive red granite head of Amenhotep III at the same temple. The head, which is about the height of a person, is the best preserved sculpture of Amenhotep III's face found to date.

Amenhotep III, who was the grandfather of the famed boy-pharaoh Tutankhamun, ruled from 1387-1348 B.C. at the height of Egypt's New Kingdom and presided over a vast empire stretching from Nubia in the south to Syria in the north.

The temple was largely destroyed, possibly by floods, and little remains of its walls.

But archaeologists have been able to unearth a wealth of artifacts and statuary in the buried ruins, including two statues of Amenhotep made of black granite found in March 2009.

Egyptian Ministry of Culture

Rare armor-plated creature discovered in Canada's capital

2010-03-17T09:06:00.001+01:00

Scientists have unearthed the remains of one of the Worlds rarest fossils - in downtown Ottawa. The 450 million year old fossil preserves the complete skeleton of a plumulitid machaeridian, one of only 8 such specimens known. Plumulitids were annelid worms - the group including earthworms, bristleworms and leeches, today found everywhere from the deepest sea to the soil in your yard - and although plumulitids were small they reveal important evidence of how this major group of organisms evolved. "Such significant new fossils are generally discovered in remote or little studied areas of the globe, requiring difficult journeys and a bit of adventure to reach them" notes Jakob Vinther of Yale University, lead author of the paper describing the specimen. "Not this one though. It was found in a place that has an address rather than map co-ordinates!"

Plumulites canadensis, Albert Street, Ottawa, Canada K1P1A4. The fossil is described by Vinther and Dave Rudkin, of Toronto's Royal Ontario Museum, in the current issue of the journal Palaeontology.

It was Rudkin who first recognised its scientific significance: "This nifty little specimen first came to my notice when I received a letter from an amateur fossil collector in Nepean, Ontario. In prospecting for fossils in rock from a temporary building excavation he had turned up a small block containing a complete trilobite, but next to it was something else and he sent me a slightly fuzzy but very intriguing photo. The mystery fossil was clearly not another trilobite, and I although couldn't be certain, I thought it might be some sort of annelid worm with broad, flattened scales. James, the collector, generously agreed to lend me the specimen and I realised immediately it was a complete, fully articulated machaeridian! The first I had ever seen."

At that time it was not known that machaeridians were annelids. "James was happy to donate the specimen to the Royal Ontario Museum, in exchange for a promise that I'd someday publish his discovery."

It was not until 2008 that Rudkin's hunch was confirmed, when a team of palaeontologists, including Jakob Vinther, decribed new machaeridian fossils from remote mountain localities in Morocco, revealing their relationship to annelid worms. Rudkin and Vinther agreed to work together to interpret the Ottawa specimen, and it is the results of that collaboration that are published in the current Palaeontology.

Plumulitid machaeridians look like modern bristleworms, with stout walking limbs bearing long bundles of bristles, but on their back they carried a set of mineralized plates. According to Vinther, "the plates themselves were rigid, but they could move relative to one other, providing plumulitids with a protective body armour very similar to the flexible metal armour invented by humans 450 million years later. Machaeridian body armour is unique among annelids, and probably helped them to succeed as ubiquitous components of marine ecosystems for more than 200 million years."

With the publication of this paper Rudkin is finally able to make good on his promise "It's great to be able to acknowledge the collector", says Rudkin, but there is a twist to this tale: the man who found the specimen has now gone missing. "Regrettably, I lost contact with James and numerous enquiries as to his whereabouts have come up empty. I hope he somehow gets wind of all this."

Wiley-Blackwell

Pottery leads to discovery of peace-seeking women in American Southwest

2010-03-12T10:02:00.000+01:00

From the time of the Crusades to the modern day, war refugees have struggled to integrate into their new communities. They are often economically impoverished and socially isolated, which results in increased conflict, systematic violence and warfare, within and between communities as the new immigrants interact with and compete with the previously established inhabitants. Now, University of Missouri researcher Todd VanPool believes pottery found throughout the North American Southwest comes from a religion of peace-seeking women in the violent, 13th-century American Southwest. These women sought to find a way to integrate newly immigrating refugees and prevent the spread of warfare that decimated communities to the north. First discovered in 1930's Arizona, Salado pottery created a debate among archaeologists. According to VanPool, the Salado tradition is a grassroots movement against violence. The mystery of the pottery's origin and significance was known as "the Salado problem." This southwestern pottery was found among three major cultural areas of the ancient southwest: the ancestral Puebloan in northern Arizona and New Mexico, the Mogollon of southern New Mexico and the Hohokam of central and southern Arizona, all with different religious traditions. Even though the pottery was found in three different cultural areas, the pottery communicated the same, specific set of religious messages. It was buried with both the elite and non-elite and painted with complex, geometric motifs and animals, such as horned serpents. Instead of celebrating local elites, the symbols in Salado pottery emphasized fertility and cooperation.

"In my view, the fact that the new religion is reflected solely in pottery, a craft not usually practiced by men, suggests that it was a movement that helped bring women together and decreased competition among females," said VanPool, who is an assistant professor of anthropology in the MU College of Arts and Science. "Women across the region may have been ethnically diverse, but their participation in the same religious system would have helped decrease conflict and provided a means of connecting different ethnic groups."

Salado pottery dates from the 13th to 15th centuries in which there was major political and cultural conflict in the American Southwest. Brutal executions and possible cannibalism forced thousands of people to abandon their native regions and move to areas of Arizona and New Mexico. Another source of conflict appeared after the female refugees and their children arrived in their new homelands.

"Conflict was defused through the direct action of women who sought to decrease the tensions that threatened to destroy their communities," VanPool said. "The rise of the Salado tradition allowed threatened communities to stabilize over much of modern-day Arizona and new Mexico, altering the course of Southwestern prehistory. Given that the Salado system lasted from 1275 to around 1450, it was most certainly successful."

University of Missouri-Columbia

Australian archaeologists uncover 40,000-year-old site

2010-03-11T08:45:00.003+01:00

Australian archaeologists have uncovered what they believe to be the world's southernmost site of early human life, a 40,000-year-old tribal meeting ground, an Aboriginal leader said Wednesday.

The site appears to have been the last place of refuge for Aboriginal tribes from the cannon fire of Australia's first white settlers, said Michael Mansell of the Tasmanian Aboriginal Centre.

The find came during an archaeological survey ahead of roadworks near Tasmania's Derwent River and soil dating had established the age of the artefacts found there.

"When the archaeological report came out it showed that (life there) had gone back longer than any other recorded place anywhere else in Tasmania, dating back to 40,000 years," Mansell told AFP.

Up to three million artefacts, including stone tools, shellfish fragments and food scraps, were believed to be buried in the area, which appeared to have been a meeting ground for three local tribes.

They died out after white settlers arrived in the late 18th century.

"They (settlers) hunted people here to this place and shot them just so they could get the land," said Mansell. "Many others were imprisoned until they died."

"In terms of culture and history this region now represents Tasmania's Valley of the Kings," he added, referring to the world heritage listed Egyptian tombs on the west bank of the Nile.

"When you get something like this that evokes memory of what your people did before we were born and evokes a memory about the legacy that they left us ... it makes the place irreplaceable."

The survey was finished last week and chief archaeologist Rob Paton said he had been surprised at the age of the items found.

"We haven't even done a reading on the bottom sample yet, I was expecting 17,000 (years) for the base of the trench and about 4 or 5,000 (years) for the top," Paton told state radio.

Paton said luminescence readings -- measuring the age of the artefacts based on how much exposure they had received to sunlight -- had been "nice and statistically tight".

"That suggests to me that they're probably correct, giving us a top reading of 28,000 (years old) and certainly seeming to go back another 10,000 (years) at least beyond that," he said.

The readings indicated that "we do have the oldest, most southern site anywhere in the world", said Paton, making it "an important site for anyone and quite exciting for us".

"I think the thing to stress is no matter what the age of the site it's important anyway," he added.

Mansell said the tribes were famous for their defiant stand against the settlers, and so frustrated the authorities they ultimately issued an order that any Aborigine in the area be shot on sight.

He said the dig's findings were merely the "tip of the iceberg" and called for plans to build a bridge over the site to be scrapped.

"The Tasmanian government must immediately declare it a protected site, not just for Aboriginal people but for peoples of the world," said Mansell.

Australia's original inhabitants, with cultures stretching back tens of thousands of years, are believed to have numbered around one million at the time of white settlement.

There are now just 470,000 out of a population of 21 million and Australia's most impoverished minority.

physorg.com