June 20, 2007, 8:27 AM CT

Uncovering Ancient Human Behaviour

A major question in evolutionary studies today is how early did humans begin to think and behave in ways we would see as fundamentally modern? One index of 'behavioural modernity' is in the appearance of objects used purely as decoration or ornaments. Such items are widely regarded as having symbolic rather than practical value. By displaying them on the body as necklaces, pendants or bracelets or attached to clothing this also greatly increased their visual impact. The appearance of ornaments may be associated with a growing sense of self-awareness and identity amongst humans and any symbolic meanings would have been shared by members of the same group.

In Europe, amongst the oldest known symbolic ornaments are perforated animal teeth and shell beads, found in Upper Palaeolithic contexts that date to no more than 40,000 years ago. Such finds are apparently linked to both modern human and late Neanderthal sites. Together with cave paintings and engravings they offer the strongest indications that European societies of those times were capable of thinking in an abstract manner, and symbolising their ideas without relying on obvious links between a meaning and a sign. But, now, a growing body of evidence indicates symbolic material culture consisting of engravings, personal ornaments and systematic use of beads had emerged much earlier in Africa......... Posted by: William      Read more         Source

June 19, 2007, 4:56 AM CT

Archaeologists rescue clues to ancient kingdom from the rising Nile

Archaeologists from the University of Chicago have discovered a gold processing center along the middle Nile, an installation that produced the precious metal sometime between 2000 and 1500 B.C. The center, along with a cemetery they discovered, documents extensive control by the first sub-Saharan kingdom, the kingdom of Kush.

The team from the Universitys Oriental Institute found more than 55 grinding stones made of granite-like gneiss along the Nile at the site of Hosh el-Geruf, about 225 miles north of Khartoum, Sudan. The region was also known also known as Nubia in ancient times.

Groups of similar grinding stones have been found on desert sites, mostly in Egypt, where they were used to grind ore to recover the precious metal. The ground ore was likely washed with water nearby to separate the gold flakes.

This large number of grinding stones and other tools used to crush and grind ore shows that the site was a center for organized gold production, said Geoff Emberling, Director of the Oriental Institute Museum and a co-leader of the expedition. The research was funded by the the National Geographic Society and the Packard Humanities Institute, which also has offered to support all the teams working in the Fourth Cataract salvage project, the location of the Universitys expedition......... Posted by: William      Read more         Source

June 13, 2007, 11:59 AM CT

Ancient Long-necked Gliding Reptile

The fossilized bones of a previously unknown, 220 million-year-old long-necked, gliding reptile may remain forever embedded in stone, but thanks to an industrial-size Computerized axial tomography scanner at Penn State's Center for Quantitative Imaging, the bone structure and behavior of these small creatures are now known.

The new gliding reptile is named Mecistrotrachelos apeoros meaning "soaring, long-necked" and was found at the Solite Quarry that straddles the Virginia-North Carolina border. The scientists report in today's (June 12) issue of the Journal of Vertebrate Paleontology that the "new specimens are embedded in a hard dolomitized dark gray, silty mudstone, and only faint impressions of the bones can be seen at the surface. Repeated attempts to remove the matrix using both mechanical and chemical techniques have been unsuccessful".

"The fossils sit on sheets of stone less than a quarter inch thick," says Tim M Ryan, research associate in anthropology and member of Penn States Center for Quantitative Imaging. "The color of the bones is the same as the color of the surrounding matrix which makes preparation difficult".

The specimens, which were found by Nick Fraser of the Virginia Museum of Natural History, came to Penn State to be scanned on the specialized Computerized axial tomography scanner......... Posted by: William      Read more         Source

June 10, 2007, 7:46 PM CT

Agonized death of dinosaurs

The peculiar pose of a number of fossilized dinosaurs, with wide-open mouth, head thrown back and recurved tail, likely results from the agonized death throes typical of brain damage and asphyxiation, as per two paleontologists.

A classic example of the posture, which has puzzled paleontologists for ages, is the 150 million-year-old Archaeopteryx, the first-known example of a feathered dinosaur and the proposed link between dinosaurs and present-day birds.

"Virtually all articulated specimens of Archaeopteryx are in this posture, exhibiting a classic pose of head thrown back, jaws open, back and tail reflexed backward and limbs contracted," said Kevin Padian, professor of integrative biology and curator in the Museum of Paleontology at the University of California, Berkeley. He and Cynthia Marshall Faux of the Museum of the Rockies published their findings in the recent issue of the quarterly journal Paleobiology, which appeared this week.

Dinosaurs and their relatives, ranging from the flying pterosaurs to Tyrannosaurus rex, as well as a number of early mammals, have been found exhibiting this posture. The explanation commonly given by paleontologists is that the dinosaurs died in water and the currents drifted the bones into that position, or that rigor mortis or drying muscles, tendons and ligaments contorted the limbs......... Posted by: William      Read more         Source

Fri, 08 Jun 2007 23:17:05 GMT

Terrible Tyrannosaurus Could Move No More Than a Leisurely Jog

When one tries to think of a real life tyrannosaur, it appears to be terrifying, needing no effort to imagine it chasing down prey with lightning speed! Am sure, you too, will draw a similar picture of its activities.

But, after all, this is fiction and its vulnerable to challenges. New computer models claim that these terrifying extinct creaactually slowpokes!

Unlike the previous studies that studied the movements of birds — the direct descendents of dinosaurs — and fossilized footprints to understand how Tyrannosaurus rex would have moved, the new study modeled a typical complete Tyrannosaurus rex skeleton to get a better estimation of the giants movement.

Probably weighing between about 13,000 and 17,000 pounds, the tyrannosaurs estimated center of mass and the inertia, or resistance to movement, would have had when it turned or pivoted.

The model results reveal that the Tyrannosaurus rex would have had inertia enough to prevent it from turning quickly, i.e. a 45-degree turn would have taken one or two seconds, which is far longer than for a human.

Thus, the front heavy Tyrannosaurus rex would have turned slowly and could manage no more than a leisurely jog, unlike what we have seen in fictionsImage Posted by: Irani      Read more     Source

April 29, 2007, 7:25 PM CT

The Chimpanzee Stone Age

Before this study, chimpanzees were first observed using stone tools in the 19th century. Now, thanks to this new archaeological find, tool use by chimpanzees has been pushed back thousands of years. The authors suggest this type of tool use could have originated with our common ancestor, instead of arising independently among hominins and chimpanzees or through imitation of humans by chimpanzees.

This study confirmed that chimpanzees and human ancestors share for thousands of years several cultural attributes once thought exclusive of humanity, including transport of raw materials across the landscape; selection and curation of raw materials for a specific type of work and projected usage; habitual reoccupation of sites where garbage and debris accumulate; and the use of locally available resources. Nut cracking behaviour in chimpanzees is transmitted socially, and the new discoveries presented in this study shows that such behaviour has been transmitted over the course of a number of chimpanzee generations. Chimpanzee prehistory has deep roots!

The study of our living closest relative, the chimpanzee, constantly highlights new aspects of human evolution, and a better protection of this endangered species will guarantee that we can continue uncovering new facets of our past. Relevant finds come from all parts of the African continent, including the rainforest, and not just the classical east African homeland......... Posted by: William      Read more         Source

Sun, 29 Apr 2007 15:51:16 GMT

42 Million-year-old Texas Fossils Unmask New Primate Genus and Species

A new genus and species of primate has been discovered. Though, long vanished from the earth it was kept preserved in the fossil record. Scienrecovered molar, pre-molar and incisor teeth from a 42 million-year-old new primate genus and also from three other new primate species.

The species were recovered from 42 million-year-old deposits in the tropical, mangrove palm swamp of the Eocene age Laredo Formation. The Formation is exposed in Lake Casa Blanca International State Park in Laredo.

The middle Eocene shoreline of the Gulf of Mexico lay 150 miles inland of its present position! This is revealed by the association of primate fossils with the skeletal remains of oysters, sharks, rays, giant aquatic snakes and crocodiles found along with mangrove palm fruits and pollen, according to Westgate — a professor of earth and space sciences at Lamar and a research associate in the Vertebrate Paleontology Laboratory, Texas Natural Science Center, University of Texas-Austin.

According to Westgate, the presence of a diverse primate community along with four species living on the Texas coast during late middle Eocene time is significant. It is because, during that period, primate diversity in North Americas northern interior had diminished greatly.

This diminution is greatly because of the cooling of the global climate and uplifting of the Rocky Mountains. The Texas coasts tropical environment seems to have allowed primates to thrive locally. Their relatives in the continental interior, on the other hand, faced near extinction. Posted by: Irani      Read more     Source

Wed, 25 Apr 2007 02:53:24 GMT

Mammal Sheds Light on Modern Mammalian

The 125 million year-old fossil remains in the Yan Mountains in what is now the Hebei Province in China have revealed a squirrel-like mammal a nThis svelte used to snag insects and worms scurrying around in the wee hours of the night.

The animal was a five-inch-long furry critter and weighed less than an ounce. It had short limbs and claws, just ideal for digging and traipsing along the ground. The animal long body was supported by 26 thoracic and lumbar vertebrae.

It seems to be very much unlike most living and extinct terrestrial mammals, which tend to be much stouter, with humans having a much larger body, but with just 33 vertebrae in their spines.

Has the high number of these vertebrae undergo genetic mutations that occurred during the deep Mesozoic time?

The nocturnal mammals fossil sheds light on the evolution of the modern ear structure! In its relatively pristine condition, the animals middle-ear structure was still attached to the lower jaw bone by Meckels cartilage.

Thus, the new fossil does not just add a new picture of what the region’s ecosystem was like in ancient times, but its ear bones position also gives a snapshot of a critical — rather until now — missing, intermediate point in the modern mammalian ears evolution. Posted by: Irani      Read more     Source

April 23, 2007, 10:43 PM CT

Prehistoric mystery organism verified as giant fungus

Researchers at the University of Chicago and the National Museum of Natural History in Washington, D.C., have produced new evidence to finally resolve the mysterious identity of what they regard as one of the weirdest organisms that ever lived.

Their chemical analysis indicates that the organism was a fungus, the researchers report in the recent issue of the journal of Geology, published by the Geological Society of America. Called Prototaxites (pronounced pro-toe-tax-eye-tees), the organism went extinct approximately 350 million years ago.

Prototaxites has generated controversy for more than a century. Originally classified as a conifer, researchers later argued that it was instead a lichen, various types of algae or a fungus. Whatever it was, it stood in tree-like trunks more than 20 feet tall, making it the largest-known organism on land in its day.

"No matter what argument you put forth, people say, well, thats crazy. That doesnt make any sense," said C. Kevin Boyce, an Assistant Professor in Geophysical Sciences at Chicago. "A 20-foot-tall fungus doesnt make any sense. Neither does a 20-foot-tall algae make any sense, but heres the fossil".

The Geology paper adds a new line of evidence indicating that the organism is a fungus. The fungus classification first emerged in 1919, with Francis Hueber of the National Museum of Natural History in Washington, D.C., reviving the idea in 2001. His detailed studies of internal structure have provided the strongest anatomical evidence that Prototaxites is not a plant, but a fungus......... Posted by: William      Read more         Source

April 23, 2007, 9:53 PM CT

First European Voyage Up the Delaware

A University of Pennsylvania scholar has pinpointed 1616 as the year of the first European voyage up the Delaware River.

Jaap Jacobs, a senior fellow at Penn's McNeil Center for Early American Studies, detailed his findings in a paper, "Truffle Hunting with an Iron Hog: The First Dutch Voyage up the Delaware River," presented to the McNeil Center Seminar Series on April 20.

Scholarly discoveries tend to be the outcome of a deliberate process, but serendipity played an important role in Jacobs' discovery of the significance of a centuries-old deposition pinpointing the year of the first Dutch voyage up the Delaware.

Sometime between 1993 and 1994 while doing research for his dissertation, Jacobs copied a summary of a document he found at the Gemeentearchief Amsterdam, the Amsterdam notarial archives. He said that the summary didn't indicate that the document was important, so he didn't look at the original until July 2000. At that point it became clear to him that the document referred to the Delaware River rather than the Hudson River, as he had originally thought. Years later, in 2007, while preparing his paper on early Dutch exploration of the Delaware and Hudson rivers, he revisited the historiography and realized that the document pertained to the first voyage up the Delaware by Europeans......... Posted by: William      Read more         Source