November 6, 2006, 5:02 AM CT

Fossils From Ancient Sea Monster

A fossil-hunting trip to celebrate a son's homecoming resulted in the recent discovery of an ancient sea monster in central Montana.

Thought to beapproximately 70 million years old, its skull and lower jaw represent the first complete skull of a long-necked plesiosaur found in Montana, as per Montana State University experts. The skull is said to be one of the best specimens of its kind in North America.

"It's a very important specimen," MSU paleontologist Jack Horner said at the Museum of the Rockies where the fossil rests in boxes. "We have been looking for it for a long, long time".

Ken Olson of Lewistown said he and his son, Garrett, found the fossils in mid-August about 75 miles northeast of Lewistown. Since Horner was in Mongolia, Olson said he prepared the fossils himself and delivered them to Horner about three weeks later. Olson, a retired Lutheran pastor, has long collected fossils for the museum. Two of his best finds are the large Torosaurus skulls displayed there.

Horner said the head of a short-necked plesiosaur was found previously in Montana, but he had been waiting for the discovery of a complete long-necked plesiosaur skull. Both were ancient sea reptiles that lived during the time of the dinosaurs.

"This critter is one of the long, ridiculously long-necked plesiosaurs," said Pat Druckenmiller, an MSU expert in marine reptile fossils. Druckenmiller, who described a new plesiosaur called Edgarosaurus from southern Montana in 2002, was part of a Norwegian expedition in August that mapped the location of several giant fossils in the Arctic. He is now an adjunct instructor in the Department of Earth Sciences at MSU.........

Posted by: William      Permalink         Source

November 2, 2006, 8:38 PM CT

human-Neandertal mixing

A reexamination of ancient human bones from Romania reveals more evidence that humans and Neandertals interbred.

Erik Trinkaus, Ph.D., Washington University Mary Tileston Hemenway Professor in Arts & Sciences, and his colleagues radiocarbon-dated and analyzed the shapes of human bones from Romania's Pe?tera Muierii (Cave of the Old Woman). The fossils, discovered in 1952, add to the small number of early modern human remains from Europe known to be more than 28,000 years old.

Results were reported in the current issue of the Proceedings of the National Academy of Science.

The team observed that the fossils were 30,000 years old and principally have the diagnostic skeletal features of modern humans. They also observed that the remains had other features known, among potential ancestors, primarily among the preceding Neandertals, providing more evidence there was mixing of humans and Neandertals as modern humans dispersed across Europe about 35,000 years ago. Their analysis of one skeleton's shoulder blade also shows that these humans did not have the full set of anatomical adaptations for throwing projectiles, like spears, during hunting.

The team says that the mixture of human and Neandertal features indicates that there was a complicated reproductive scenario as humans and Neandertals mixed, and that the hypothesis that the Neandertals were simply replaced should be abandoned.........

Posted by: William      Permalink         Source

November 1, 2006, 3:50 PM CT

Missing Link In Elephant Lineage

A pig-sized, tusked creature that roamed the earth some 27 million years ago represents a missing link between the oldest known relatives of elephants and the more recent group from which modern elephants descended, an international team that includes University of Michigan paleontologist William J. Sanders has found.

The group's findings, would be published this week in the Proceedings of the National Academy of Sciences, suggest that mastodons and the ancestors of elephants originated in Africa, in contrast to mammals such as rhinos, giraffes and antelopes, which had their origins in Europe and Asia and migrated into Africa. The dating of the new fossil, discovered in the East African country of Eritrea, also pushes the origins of elephants and mastodons five million years farther into the past than prior records, Sanders said.

From 35 to 25 million years ago, representatives of the group known as proboscideans (which includes elephants, mastodons and their close relatives) lived only in Africa and Arabia, and most of them were palaeomastodonts. These animals were shorter and smaller than today's elephants, with short trunks and tusks and simple teeth that were all in place at the same time, as human adult teeth are.

After 25 million years ago, larger proboscideans such as mastodons and gomphotheres-the ancestors of modern elephants-dominated the scene. Elephant-sized, with long tusks and trunks, these advanced proboscidans had more complex teeth that emerged more slowly, so that each quadrant of the mouth had only one or two functional teeth in place at a time.........

Posted by: William      Permalink         Source

November 1, 2006, 4:04 AM CT

Recovering Pompeii

Artists in ancient Pompeii painted the town red 2,000 years ago with a brilliant crimson pigment that dominated a number of of the doomed city's wall paintings. Now researchers from France and Italy are reporting in the journal Analytical Chemistry why those paintings are undergoing a mysterious darkening. The synchrotron light of the European Synchrotron Radiation Facility (ESRF) in Grenoble (France) has provided new insight into this process and what produces it.

On 24 August of the year 79 AD, the volcano Vesuvius erupted burying its neighbouring towns in pumice and ash. The Villa Sora, in Torre del Greco, had since then remained inexistent, until twenty years ago, when excavation works brought it back to light. In the remains of the house, the distinctive red colour of the wall frescoes has turned black in a number of places since the excavation in a quick degradation process which is not well understood scientifically.

Researchers have been wondering for a number of years why the red in Pompeii walls, made of cinnabar (HgS), turns black. Already in the 1st century BC, Vitruvius, in his treatise "De Architectura", mentions the problem, which at that time, was prevented by applying a sort of protective varnish based on "punic wax". The causes and mechanisms responsible for cinnabar discolouration have remained a mystery until now; consequently conservators are unable to prevent the phenomenon from ocurring. The most usually acknowledged answer is that the exposure to the sun transforms cinnabar into another phase, metacinnabar, which is presented in a black colour. Recently a Franco-Italian team of scientists had studied four samples of wall paint from Villa Sora using the ESRF synchrotron light to verify whether this statement was correct.........

Posted by: Sarah      Permalink         Source

October 29, 2006, 7:45 PM CT

Untold Stories Of Elk Skeleton

Seeing the well-preserved antlers, skull and partial skeleton of a very large elk that was found in northern Wisconsin was impressive enough. But what really intrigued Jean Hudson was what was found nearby - a Clovis point, a type of spearhead used by hunters from about 10,000 years ago.

Very few have been found this far north, and this spearhead may be the one that doomed the animal all those millennia ago, says Hudson, an associate professor of anthropology. Or the two specimens could be completely unrelated, she says.

If the two are linked, it would mean that the elk remains are particularly rare. More physical evidence of animals such as mastodons, wooly mammoths and giant bison exists than that of elk, says Hudson.

But decoding the secrets of an animal skeleton requires asking the same questions you would at a crime scene investigation: What were the time, cause and circumstances of death? It also involves sometimes getting it wrong, leading to new questions.

A swimmer discovered the antlers of what appears to be a prehistoric elk at the bottom of Middle Eau Claire Lake in Barnes, Wis., last summer. Matt McKay of the Department of Natural Resources in Hayward, who is assigned to the maintenance of the Clam Lake elk herd, estimated the elk would have been between 1,000 and 1,100 pounds when it was alive.........

Posted by: Ashley      Permalink         Source

October 27, 2006, 5:18 AM CT

What Killed Dinosaurs 65 Million Years Ago

Growing evidence shows that the dinosaurs and their contemporaries were not wiped out by the famed Chicxulub meteor impact alone, as per a paleontologist who says multiple meteor impacts, massive volcanism in India and climate changes culminated in the end of the Cretaceous Period.

The Chicxulub impact may have been the lesser and earlier of a series of meteor impacts and volcanic eruptions that pounded life on Earth for more than 500,000 years, say Princeton University paleontologist Gerta Keller and her collaborators Thierry Adatte from the University of Neuchatel, Switzerland, and Zsolt Berner and Doris Stueben from Karlsruhe University in Gera number of.

A final, much larger and still unidentified impact 65.5 million years ago appears to have been the last straw, said Keller, exterminating two-thirds of all species in one of the largest mass extinction events in the history of life. It's that impact - not Chicxulub - that left the famous extraterrestrial iridium layer found in rocks worldwide that marks the impact that finally ended the Age of Reptiles, Keller believes.

"The Chicxulub impact alone could not have caused the mass extinction," said Keller, "because this impact predates the mass extinction".

Keller is scheduled to present that evidence at the annual meeting of the Geological Society of America (GSA) in Philadelphia, on Tuesday, October 24, 2006.........

Posted by: William      Permalink         Source

October 24, 2006, 8:51 PM CT

Early Bronze Age Mortuary Complex Discovered

An ancient, untouched Syrian tomb that wowed the archaeological world on its discovery by Johns Hopkins University scientists nearly six years ago has revealed another secret: It is not alone.

The tomb, which was filled with human and animal remains, gold and silver treasures and unbroken artifacts dating back to the third millennium B.C., is actually one of at least eight located near each other in Umm el-Marra, archaeologist Glenn Schwartz said. That northern Syrian city is thought to bethe site of ancient Tuba, one of Syria's first cities and the capital of a small kingdom, said Schwartz, the Whiting Professor of Archaeology in the Department of Near Eastern studies at Johns Hopkins.

The newly discovered tombs contain signs of the ritual sacrifice of humans and animals, including the skeletons of infants and decapitated donkeys, as well as puppy bones, Schwartz said. "Given these discoveries, it's likely that the tomb complex is a royal cemetery," he said.

"Animal sacrifices were certainly a big part of this culture in that offerings of sheep and other animals are given to the gods to eat and also given to deceased royal ancestors," Schwartz said. He and his team have dubbed this site the Acropolis Center mortuary complex.

The tombs are located about 35 miles east of the site of Aleppo, the main city and dominant center in the region dating at least as far back as 2000 B.C., Schwartz said. Though the tomb complex is much less showy than the famous one from the same period at Ur in Mesopotamia, which is now Iraq, the Umm el-Marra complex is the only known one in Syria from this time period.........

Posted by: William      Permalink         Source

October 24, 2006, 8:18 PM CT

Amazon River Reversed Flow

Ask any South American dinosaur which way the Amazon River flows and she would have told you east-to-west, the opposite of today. That's the surprising conclusion of scientists studying ancient mineral grains buried in the Amazon Basin.

The once westward roll of what is now the world's largest river was caused by a long-gone highland near what today is the river's mouth. That highland was created by the breaking away of South America from Africa and the creation of the Atlantic Ocean during the Cretaceous Period, 65 to 145 million years ago. Later, when the Andes rose up on the western side of South America, the river had no choice but to drain into the new ocean.

"It just happened in a way that the current Amazon could take advantage of where an old river and ocean basin used to sit," said geologist Russell Mapes, a doctoral candidate at the University of North Carolina in Chapel Hill.

Prior Brazilian and U.S. scientists have proposed smaller scale reversals and splits in the Amazon Basin, but nothing on the scale of the entire basin, said Mapes.

The evidence for the Amazon's ancient switcheroo comes in the form of tiny crystals of a mineral called zircon, as well as telltale signs of the river flow direction captured in the structure of old river sediments.........

Posted by: William      Permalink         Source

October 24, 2006, 7:26 PM CT

New Theory For Mass Extinctions

A new theory on just what causes Earth's worst mass extinctions may help settle the endless scientific dust-up on the matter. Whether you favor meteor impacts, volcanic eruptions, cosmic rays, epidemics, or some other cause for the worst mass extinction events in Earth's history, no single cause has ever satisfied all researchers all the time for any extinction event. That may be because big extinctions aren't simple events.

The new Press/Pulse theory gets around the controversy by rejecting the all-or-nothing approach to mass extinction, calling instead on a combination of deadly sudden catastrophes - "pulses" - with longer, steadier pressures on species - "presses".

"What we wanted to do is move away from the idiosyncratic approach to extinction mechanisms and look for what these intervals had in common. If you have A and B you will get a mass extinction," said Ian West, a 2006 graduate of Hobart and William Smith Colleges in Geneva, NY.

West and Hobart and William Colleges paleontology professor Nan Crystal Arens are scheduled to present their work on the Press/Pulse theory on Wednesday, 25 October, at the Annual Meeting of the Geological Society of America in Philadelphia.

Using databases that chart genera of marine organisms and their extinctions through the fossil record, West and Arens divided the last 488 million years of geologic history into four groups: times of suspected impact events (Pulses), times of massive volcanic eruptions (Presses), times when neither Presses nor Pulses occurred, and times when Press and Pulse coincided. They compared average extinction rates in geologic stages in each of these groups.........

Posted by: William      Permalink         Source

October 24, 2006, 7:11 PM CT

Trotting With Emus To Walk With Dinosaurs

One way to make sense of 165-million-year-old dino tracks may be to hang out with emus, say paleontologists studying thousands of dinosaur footprints at the Red Gulch Dinosaur Tracksite in northern Wyoming. Because they are about the same size, walk on two legs and have similar feet, emus turn out to be the best modern version of the enigmatic reptiles that once trotted along a long-lost coastline in the Middle Jurassic.

"We don't have any documented dinosaur bones and teeth from that period in North America, except for some very scrappy material from Mexico," said Brent Breithaupt, curator and director of the University of Wyoming's Geological Museum in Laramie, Wyo. That makes it very hard to connect the tracks to a particular dinosaur. And of course, "We unfortunately can't go out and see walking dinosaurs today. Or can we?".

After scouring the dinosaur fossil record in other parts of the world and deciding that a human-sized, meat-eating dinosaur (theropod) fit the bill for the tracks at Red Gulch, Breithaupt and his colleagues and students did something unusual. Instead of speculating about what the dinosaurs were doing, they went hunting for a modern analog animal they could study to help decipher the tracks.

Large flightless birds are the most logical choice and are, along with all birds today, thought to be descended from dinosaurs. But not all of those alive today are good choices or easy to work with. Ostriches are two-toed and have an attitude problem, so that ruled them out, says Breithaupt. Rheas have three toes, but are "like working with a bunch of kindergarteners on too much sugar," he said.........

Posted by: William      Permalink         Source