Dinosaurs: New Findings & Theories

[ramonmercado]

Dino-Era "Sea Monster" Found on Arctic Island
James Owen
for National Geographic News

October 6, 2006
A dinosaur-era Davy Jones's locker of large, predatory sea reptiles—including a giant that scientists have nicknamed "the Monster"—has been discovered by fossil hunters on an Arctic island.

The ancient graveyard once lay deep underwater during the Jurassic period, about 200 million to 145 million years ago (take a virtual swim with Jurassic sea monsters).

The site now sits on the island of Spitsbergen, part of the Norwegian-owned Svalbard archipelago, which lies about 600 miles (966 kilometers) from the North Pole (map of Norway).

In total, 28 well-preserved skeletons of marine reptiles that lived some 150 million years ago have been identified at the site, reports a team from the University of Oslo Natural History Museum in Norway.

The fossil haul includes the Monster, an estimated 33-foot-long (10-meter-long) pliosaur that has not yet been fully excavated. (See images of the newly found sea monster.)

Pliosaurs were the top marine predators during a time when the oceans were teeming with large, meat-eating reptiles.

"It was the T. rex of the ocean," said Jørn Hurum, co-leader of the research team. "It would have eaten everything."

So far the team has found the Monster's skull, which measures 6.9 feet (2.1 meters) in length, along with dinner plate-size neck vertebrae and portions of the lower jaw containing teeth as thick as cucumbers.

The fossil specimen may represent the largest complete pliosaur ever found, Hurum says.

"It looks very promising, because we've got 6 meters [20 feet] of vertebrae and the skull and part of a flipper, so it's probably complete," Hurum said.

Black Mud

In addition to the Monster, the researchers uncovered 6 ichthyosaurs and 21 plesiosaurs during a two-week expedition to Spitsbergen in August.

Pliosaurs are believed to be closely related to plesiosaurs. But pliosaurs had short necks and massive jaws that would have been capable of lifting a car and biting it in half.

Such strength likely helped the pliosaurs hunt prey such as plesiosaurs and ichthyosaurs, another group of marine reptiles.

Ichthyosaurs resembled dolphins but used an upright tail fin, as opposed to dolphins' sideways tail fins, to propel themselves through the water.

Most ichthyosaurs averaged 13 to 20 feet (4 to 6 meters) in length, but some reached 75 feet (23 meters).

The new find follows up on fieldwork on Spitsbergen in 2004, when University of Oslo researchers excavated parts of the skulls of an ichthyosaur and two plesiosaurs.

The fossils from both digs were found in a layer of black shale—a type of sedimentary rock—that is between 65 to 100 feet (20 to 30 meters) thick.

"There's something special about the chemistry of the shale which has preserved all the bones in this layer," Hurum said.

According to Hurum, when the reptiles died they probably sank to the ocean floor, where conditions were right for preserving their bodies.

"It's deep water and black mud that they fell into. There were no animals living close to the bottom that could eat these big things that were decaying," he said.

"One specimen [we found] was probably scavenged before it fell to the bottom, but the others look quite complete, and that's amazing," Hurum said.

This summer marine reptile expert Pat Druckenmiller, of Montana State University in Bozeman, accompanied the team to Svalbard.

Druckenmiller, who identified the large pliosaur, said that "it is certainly likely that some of these animals represent new types of plesiosaurs and ichthyosaurs that are unknown to science."

The paleontologist says that many of the fossil reptiles are well articulated.

"This means that if you find the tail sticking out of the hill and you follow it in, you have a good chance of finding the rest of the skeleton—including the all-important skull—also attached," he said.

"This type of preservation, in black shale, is one of the settings considered likely to preserve traces of the animals' soft tissues, such as skin impressions," he added.

Dreams of Eggs

Druckenmiller says that the find shows that the Svalbard island chain is "significant at a global level," in terms of the quality of fossil preservation and the number and different types of marine reptiles found.

The site also provides "a relatively complete chapter from the late Jurassic, about 150 million years ago," he added.

"This age is considered one of the heydays of marine reptile life, but what we know of life from this specific window of time only comes from scattered sites around the globe."

The Oslo team is hopeful that the fossil graveyard will yield important new clues to the history and biology of these ocean predators.

"The dream is that one of the plesiosaurs or the pliosaur was pregnant" when it died, the University of Oslo's Hurum said. "A pregnant one, or one with eggs inside, is not known anywhere in the world."

Researchers still aren't sure if these creatures gave birth to live young underwater or if they hauled themselves on land to lay eggs like modern sea turtles.

Also, having the remains of both young and adult plesiosaurs could shed light on how the reptiles grew and matured, Hurum adds.

The researchers will return to the Arctic island next summer, when they plan to finish excavating the pliosaur and several other specimens.


http://news.nationalgeographic.com/news ... tiles.html

 

[ramonmercado]

Ancient 'Jaws' had monster bite

Ancient 'Jaws' had monster bite

The fish would have been a formidable predator
A prehistoric "Jaws" that roamed the seas 400 million years ago had the most powerful bite of any known fish.
The extinct creature, Dunkleosteus terrelli, could bring its jaws together with a remarkable force of 5,000 Newtons (1,100lbs-force).

This performance surpasses all living fish, including today's great white shark, and puts it up with some of the most powerful bites in all animals.

Details appear in the UK Royal Society journal Biology Letters.

US researchers Mark Westneat and Philip Anderson tell the journal that higher bite forces have only been reported for some large alligators and dinosaurs.

T. rex, for example, could clamp down on its meal with a crushing force of 13,000 Newtons (3,000lbs-force); but a modern spotted hyena, by comparison, exerts a force of only 2,000 Newtons (500lbs-force) when it cracks bones in its mouth.

The team developed its biomechanical model of Dunkleosteus by studying the fossil remains of the fish, which probably grew up to 10m (30ft) in length.

The scientists say the way its teeth were organised in the jaw meant it could focus its bite into a small area - the fang tip - with the incredible pressure of nearly 150 million Pascals (22,000lbs per sq inch).

Even more surprising is the fact that Dunkleosteus could also open its mouth very quickly - in just one fiftieth of a second - which created a strong suction force, pulling fast prey into its mouth.




"This heavily armoured fish was both fast during jaw opening and quite powerful during jaw closing," said Westneat, who is curator of fishes at The Field Museum in Chicago.
"This is possible due to the unique engineering design of its skull and different muscles used for opening and closing."

Usually, a fish has either a powerful bite or a fast bite, but not both.

The formidable fish was a placoderm, a diverse group of armoured fish that dominated aquatic ecosystems during the Devonian Period, from 415 million to 360 million years ago.

"Dunkleosteus was surrounded by possible prey that all required really high bite force," said Anderson, who works out of the University of Chicago.

"There were free-swimming, fast animals that all had a hard armour; most of the other fish were other placoderms which had the same hard bony covering. And then there were large molluscs with hard shells and really large crustaceans," he told BBC News.




http://news.bbc.co.uk/2/hi/science/nature/6195188.stm

 

[ramonmercado]

Study Finds That A Single Impact Killed The Dinosaurs

"It's remarkable the degree to which our samples follow predictions given a mass extinction caused by a single impact..." - Ken MacLeod.
by Staff Writers
Columbia MO (SPX) Nov 30, 2006
The dinosaurs, along with the majority of all other animal species on Earth, went extinct approximately 65 million years ago. Some scientists have said that the impact of a large meteorite in the Yucatan Peninsula, in what is today Mexico, caused the mass extinction, while others argue that there must have been additional meteorite impacts or other stresses around the same time.
A new study provides compelling evidence that "one and only one impact" caused the mass extinction, according to a University of Missouri-Columbia researcher.

"The samples we found strongly support the single impact hypothesis," said Ken MacLeod, associate professor of geological sciences at MU and lead investigator of the study. "Our samples come from very complete, expanded sections without deposits related to large, direct effects of the impact - for example, landslides - that can shuffle the record, so we can resolve the sequence of events well.

"What we see is a unique layer composed of impact-related material precisely at the level of the disappearance of many species of marine plankton that were contemporaries of the youngest dinosaurs. We do not find any sedimentological or geochemical evidence for additional impacts above or below this level, as proposed in multiple impact scenarios."

MacLeod and his co-investigators studied sediment recovered from the Demerara Rise in the Atlantic Ocean northeast of South America, about 4,500 km (approximately 2,800 miles) from the impact site on the Yucatan Peninsula. Sites closer to and farther from the impact site have been studied, but few intermediary sites such as this have been explored. Interpretation of samples from locations close to the crater are complicated by factors such as waves, earthquakes and landslides that likely followed the impact and would have reworked the sediment.

Samples from farther away received little impact debris and often don't demonstrably contain a complete record of the mass extinction interval. The Demerara Rise samples, thus, provide an unusually clear picture of the events at the time of the mass extinction.

"With our samples, there just aren't many complications to confuse interpretation. You could say that you're looking at textbook quality samples, and the textbook could be used for an introductory class," MacLeod said. "It's remarkable the degree to which our samples follow predictions given a mass extinction caused by a single impact. Sedimentological and paleontological complexities are minor, the right aged-material is present, and there is no support for multiple impacts or other stresses leading up to or following the deposition of material from the impact."

The impact of a meteorite on the Yucatan Peninsula likely caused massive earthquakes and tsunamis. Dust from the impact entered the atmosphere and blocked sunlight, causing plants to die and animals to lose important sources of food. Temperatures probably cooled significantly around the globe before warming in the following centuries, wildfires on an unprecedented scale may have burned and acid rain might have poured down.

MacLeod and many other scientists believe that these effects led to the relatively rapid extinction of most species on the planet. Some other scientists have argued that a single impact could not have caused the changes observed and say that the impact in the Yucatan predates the mass extinction by 300,000 years.

MacLeod's co-investigators were Donna L. Whitney from the University of Minnesota, Brian T. Huber from the Smithsonian National Museum of Natural History and Christian Koeberl of the University of Vienna. The study was recently published in the 'in press' section of the online version of the Geological Society of America Bulletin. Funding was provided by the U.S. Science Support Program, the U.S. National Science Foundation and the Austrian Science Foundation. Samples were recovered on Leg 207 of the Ocean Drilling Program.


Bye Bye Dino

 

[ramonmercado]

Researchers Unveil Nev. Dinosaur Fossils

(AP) -- Nevada's state fossil, the giant ocean-roaming fish-reptile known as the ichthyosaur, will have to share the scientific stage after researchers this week unveiled the first fossils of land-based dinosaurs ever found in Nevada.

The discovery expands the known range of the prehistoric beasts and offers a new understanding of life in the state some 100 million years ago.

Put on display for the first time Thursday were the femur of the raptor, dromaeosaur, the teeth of a sauropod, a tyrannosauroid and an iguanodont and unidentified dinosaur eggshell fragments.

The remnants, found at secret excavation sites in southern Nevada, pushed the known range of the ancient reptiles about 250 miles farther west, said Joshua Bonde, a graduate earth science student at Montana State University who is leading the dig.

"Most of these groups of dinosaurs are known from other places in the United States," he said. "What we're able to do is push the ranges of these animals all the way up to Nevada now, where previously the farthest west they've been is east-central Utah."

The find was presented in a tent on the site of a future state museum where they will be housed.

It marked a breakthrough in a state that had only turned up marine fossils until now, said Eugene Hattori, the state's curator of anthropology.

The state was largely underwater or nonexistent when the ichthyosaur swam the seas more than 200 million years ago. While the seas receded and the area became land about 145 million years ago, evidence of ancient land-based animals in Nevada previously did not exist.

"We were getting seashells, ammonites and crinoids and that sort of thing, and ichthyosaurs, the big fish, but we have not had the terrestrial fossils until Josh did his work," Hattori said.

Geology professor Stephen Rowland of the University of Nevada, Las Vegas, said the scientific community once didn't expect to find evidence of dinosaurs in Nevada even though there were dry-land rocks here from the Mesozoic age.

"Now we can put animals on the land. It helps us understand the whole landscape much more clearly," he said.

Bonde and his supervisor, Montana State paleontologist Dave Varricchio, discovered the site while prospecting in an area that had rock formations dating to the dinosaur age.

They found fossils of turtle shells and dinosaur teeth on the surface of what later became an excavation site in March 2005.

"If you find fossils on the surface, it's kind of like smoke, like there's something else," Bonde said. "Hopefully this is the tip of the iceberg."

The area is believed to have once been a flood plain where the creatures lived and died for many generations from 99 million to 112 million years ago, Bonde said.

"When it floods you get all this mud on the surface outside the river channel. Those muds are what we find most of these fossils in," he said.

Bonde said he plans to publish the findings in a leading paleontological journal. The beneficiary of some of the artifacts will be the new Nevada State Museum, which is expected to open in July 2008 at the Springs Preserve site in Las Vegas.

The public won't be see the items until then, when they will likely be part of a larger exhibit, museum director Greta Brunschwyler said.

"It's just fantastic for the people of Nevada, because we didn't even think we had dinosaurs here," she said.

---

On the Net:

Springs Preserve, http://www.springspreserve.org

http://www.physorg.com/printnews.php?newsid=84217781

 

[ramonmercado]

Published online: 12 December 2006; | doi:10.1038/news061211-4
Rare reptile fossil found in Antarctica
Researchers battle inclement weather to excavate juvenile plesiosaur remains.
Heidi Ledford



Digging in the cold for fossils.

James E. Martin, South Dakota School of Mines and Technology

James Martin and the other eight members of his expedition to Antarctica are no strangers to hardship. They have camped out in freezing temperatures, endured week-long wind storms, and hiked across frozen terrain carrying heavy equipment.

The reward: a rare fossil of a juvenile reptile that patrolled the Southern Ocean 70 million years ago. It is the most complete fossil of its kind, and will be displayed at the South Dakota School of Mines and Technology's Museum of Geology in Rapid City on 13 December.

The fossil is what remains of a baby plesiosaur, less than 1.5 metres long. Plesiosaurs, despite the name, were aquatic reptiles and not dinosaurs — which are by definition terrestrial. They had long necks, a small head and four large flippers for swimming. A full-grown plesiosaur would measure about 10 metres from the top of its tiny head to the tip of its short tail.

This particular plesiosaur hails from an era when the Southern Ocean was warmer and Antarctica was covered with conifers and ferns, its climate more similar to today's southern South America than the frozen land we now know. The fossil was found in the ground (not the ice) of Vega Island, which lies off the Antarctic Peninsula.

It's hard to find fossils of juveniles, in part because when young animals met an untimely death it was usually at the jaws of predators, not leaving a skeleton behind. Because this fossil was surrounded by volcanic ash, researchers think that the young plesiosaur was caught in a cataclysmic volcanic eruption. Tony Fiorillo, a palaeontologist at the Dallas Museum of Nature and Science, Texas, also points out that infant fossils are hard to find because juvenile bones are not as well ossified as adult bones, and fall apart more easily over time.

"Baby plesiosaurs are super rare," says Benjamin Kear of the University of Adelaide in Australia who studies plesiosaurs of all ages. "To get a really good one is just fantastic."

With or without mum




Artist's drawing of a pleisosaur.

Trent Schindler, National Science Foundation

Kear says that studying the features of a juvenile plesiosaur can reveal details about the animal's life history, such as how independent young plesiosaurs were of their mothers. "If the teeth are well worn, the baby could have been feeding on its own," says Kear. Palaeontologists can also look at the skulls, he adds. Well-fused skull bones would suggest an ability to deal with struggling prey — a factor governing whether the juvenile is robust enough to survive on its own.

Unfortunately, neither approach is possible with the current fossil because the skull was never found. The team searched for it, but inclement weather forced them to give up their pursuit.

Lousy weather was a theme of the research expedition. The wind tossed gravel into the researchers' faces and made unearthing the fossil a great challenge. "We would uncover a few vertebrae and the wind would cover them back up," says Martin, who is at the South Dakota School of Mines and Technology's Museum of Geology. One week the wind speed reached 110 kilometres per hour. "And then it got cold," he adds.

Shame about the weather

After the team had excavated around the fossil, they needed to cover it in plaster, wrap it in canvas, and remove it from its resting place. That job took around 45 kilograms of plaster and a jackhammer — both of which the researchers carried from the base camp to the excavation site. They eventually pried the fossil free and airlifted it away by helicopter.

Fiorillo says these harsh weather tales sound all too familiar. He has been looking for fossils in northern Alaska since 1998, and describes the weather during his latest trip in August as "absolutely miserable". "We probably spent 40-50% of the time cooped up in our tents waiting for the weather to improve," he says. Nevertheless, the region has rewarded him with a rich diversity of fossils ranging from duckbill dinosaurs to pachycephalosaurs.

Fiorillo says the weather may not be quite as rough in Alaska as it is in the Antarctic, but that doesn't mean life is easy: "We also have to deal with grizzly bears."



Story from [email protected]:
http://news.nature.com//news/2006/061211/061211-4.html

 

[ramonmercado]

Two-headed reptile fossil found

The reptile was unearthed in rocks from northeastern China
Scientists have found what is thought to be the first example of a two-headed reptile in the fossil record.
The abnormal animal, belonging to a group of aquatic reptiles, was unearthed in northeastern China and dates to the time of the dinosaurs.

The specimen reveals that it must have been very young when it died and became fossilised, says lead researcher Eric Buffetaut.

Details of the fossil appear in the UK Royal Society journal Biology Letters.

This animal was a choristoderan, an extinct reptile that reached a length of one metre in adulthood and was characterised by a long neck - two in this case.

The animal's spinal column divided in two at the point where the neck emerges from the body. This formed two long necks that ended in two skulls.

Choristoderans seem to have been common aquatic reptiles during the Cretaceous Period (144 to 65 million years ago) in what is now northeastern China.

"To my knowledge, it is the only record of a vertebrate fossil showing that kind of malformation," Dr Buffetaut, director of research at the Centre National de la Recherche Scientifique (CNRS) in Paris, France told BBC News.


More than 400 two-headed snakes have been recorded


Two-headed snake
"Living animals like this are known. But if you compare the number of reptiles born with two heads with the total number of reptiles born, it is very small.

"So the chances of finding a fossil like this are extremely low."

The abnormality is known to occur with some frequency in modern reptiles; about 400 cases of two-headed snakes have been recorded in historic times.

It is thought this can occur as a result of injury to an embryo.

The specimen comes from Cretaceous rocks in the Yixian Formation of northeastern China. It is now held at the Shenzhen Museum in southern China.


http://news.bbc.co.uk/2/hi/science/nature/6195345.stm

 

[Dingo667]

Ooooh, dragons spring to mind :shock:

 

[feen5]

Or the Hydra

 

[ramonmercado]

Stones Did Not Help Dinosaurs' Digestion

The researchers believe, instead of stones, the intestines of dinosaurs were formed in such a way that food was retained for a very long time to improve the digestive process.
by staff writers
Tubingen, Germany (UPI) Dec 20, 2006
German scientists say their research suggests the idea that dinosaurs swallowed stones to help them digest food might be incorrect.
Many dinosaurs had narrow, pointed teeth that were more suited to tearing off plants rather than chewing them. So many researchers assumed the giant animals were helped by stones they swallowed, which acted as a kind of gastric mill.

But Oliver Wings of the Institute of Earth Sciences at the University of Tubingen, and Martin Sander from the University of Bonn have cast doubt on the theory.

For the study, the scientists offered stones such as limestone, rose quartz and granite as food to ostriches -- relatives of dinosaurs.

After the ostriches had been slaughtered, the scientists investigated the gastric stones. It became clear the stones wore out quickly in the muscular stomach and were not polished. That suggests they were not remains of a gastric mill, Sander said.

The researchers believe, instead of stones, the intestines of dinosaurs were formed in such a way that food was retained for a very long time to improve the digestive process.

The study is detailed in the current issue of the Proceedings of the Royal Society.


Digestion

 

[ramonmercado]

Europe's 'biggest dinosaur' found

Giant on the shore


Enlarge Image

Fossils found in Spain belong to what was probably Europe's biggest ever dinosaur, according to scientists.

Turiasaurus would have been 30 to 37 metres long, and would have weighed between 40 and 48 tonnes.

Writing in the journal Science, researchers say the beast is probably the only member so far discovered of a European group of Jurassic reptiles.

The world's biggest recorded dinosaur is Argentinosaurus, a South American reptile twice as heavy.

Like the rest of the giant long-necked sauropods, Turiasaurus riodevensis was a herbivore, despite the fierce appearance of its teeth.

Big-boned

Fossils came to light in 2004 at Teruel in eastern Spain, and the scientists responsible, from the Fundacion Conjunto Paleontologico de Teruel-Dinopolis, have just published a formal analysis.

Although languishing some way behind Argentinosaurus, Turiasaurus was a substantial specimen.



Many of the details of Turiasaurus are inferred from its teeth

At 1.79m long, its humerus (upper arm bone) is one of the largest ever recorded, while one of its claws is comparable with a rugby ball or American football.
The discovery site also contains teeth from theropod dinosaurs, Stegosaurus remnants, and fragments from fish and turtles.

By comparing its features with other European dinosaurs, the scientists deduce that it belongs to a previously unknown clade, or grouping, which evolved in the Jurassic period (200 to 145 million years ago).

Teeth excavated in France, Portugal and the UK are similar, indicating that Turiasaurus, or more likely its close relatives, ranged across the continent.


http://news.bbc.co.uk/2/hi/science/nature/6201251.stm

 

[ramonmercado]

Flying dinos had bi-plane design

Microraptor was a small, feathered dinosaur
The first flying dinosaurs took to the air in a similar way to a World War I bi-plane, a study shows.
A fresh analysis of an early feathered fossil dinosaur suggests that it dropped its hind legs below its body, adopting a bi-plane-like form.

This contrasts with earlier reconstructions showing the dinosaur maintaining its wings in a tandem pattern, a bit like a dragonfly.

Details appear in Proceedings of the National Academy of Sciences journal.

The ancestors of modern birds are thought to have been small, feathered, dinosaurs.

Microraptor gui, which lived 125 million years ago, was one of the earliest gliders. It appears to have utilised four wings, as it had long and asymmetric flight feathers on both its hands and feet.

Spread 'em

An initial assessment of Microraptor fossils from China suggested the animal spread its legs out laterally and maintained its wings in a tandem pattern, in a similar manner to dragonflies.

Now, researchers Sankar Chatterjee and R Jack Templin offer an alternative hypothesis.


The evolution of bird flight may mirror aviation history
Their evaluations of the limb joints and feather orientation indicate that a tandem wing design would neither have achieved suitable lift, nor enabled Microraptor to walk on the ground easily.

Instead, the scientists report that its hind legs were positioned below the body, in a bi-plane fashion.

Dr Chatterjee, from Texas Tech University in Lubbock, US, explained that two lines of evidence had led the team to this conclusion.

Firstly, the researchers argue, dinosaurs and birds move their legs in a vertical plane, not sideways as the tandem flight pattern requires.

Secondly, the feathers on Microraptor's hind legs are asymmetrical; one of the two vanes that extend either side of the shaft is narrower than the other.

Forward facing

Aerodynamically, the narrow leading edge of these feathers should face forward in flight, against the direction of airflow. This would have given the flying reptiles lift.

In the tandem pattern, these would have faced sideways.

"We had no other choice but to go for the bi-plane configuration," Dr Chatterjee told BBC News.


The similarities may reflect a common solution to the same problem (Image: Jeff Martz)
A computer flight simulation using this design showed that Microraptor would undulate up and down, an ideal approach for gliding between trees.

The research might also shed light on a contentious debate over the evolution of bird flight.

Some researchers argue that this evolutionary development occurred from the ground up. Others contend that small, feathered dinosaurs were already living in treetops and developed flight in order to get from one tree to another.

This "trees down" model is the one favoured by Chatterjee and Templin.

Alternatively, the bi-plane-like phase could just represent a failed evolutionary experiment.

The Wright stuff

If one accepted the evolutionary importance of the bi-plane formation, there were striking parallels between bird flight and the development of aircraft, said Dr Chatterjee.

Archaeopteryx, regarded as the earliest fossil bird, has what could be described as a monoplane design.

The shift from a bi-plane to a monoplane design could have been facilitated by a much broader wingspan which would have provided increased lift. This mirrors historical developments in aviation.

"We see that the Wright brothers came up with a design for which there was no precedent in nature at the time," said Dr Chatterjee.

"This shows us that if there is a problem in engineering, sometimes there are only one or two possible solutions."


http://news.bbc.co.uk/2/hi/science/nature/6287367.stm

 

[ramonmercado]

Birdlike dinosaur boasted opposable fingers
10:45 29 January 2007
NewScientist.com news service
Jeff Hecht

Bambiraptor was apparently able to use its outer claws as pincers, to grab its unfortunate prey (Illustration: Phil Senter)

Bambiraptor skeleton in the Oxford University Museum of Natural History in the UK Chalk up another evolutionary first for dinosaurs: Bambiraptor evolved opposable fingers 75 million years ago, long before our ancestors developed opposable thumbs.

Phil Senter at Lamar State College in Orange, Texas, US, made the discovery while investigating the arm movements that could have been made by a dromeosaur called Bambiraptor. The team were studying an exceptionally well-preserved example of the predatory dinosaur, about as tall as a man's knee.

Working with models of the bones, Senter found that Bambiraptor would have been able to hold prey with both arms, or use its long arms to bring objects to its mouth. But he was surprised to find that it would have been possible for the dinosaur to put the tips of the outer two of its three fingers together, the way a human can touch the tip of the thumb to the tip of the third finger – a trait Senter says is not known in any other dinosaur.

Most predatory dinosaurs grabbed prey with their mouths, but Senter says that Bambiraptor might have grabbed prey like a frog or small mammal with one hand. Sharp claws on its fingertips could impale prey from both sides and prevent it from escaping. "Caterpillars would be perfect to grab between claws" and drop into its mouth, Senter told New Scientist.

Although the fossil preserved no trace of feathers, dromeosaurs were close relatives of birds, and the most primitive one yet found, Microraptor, had long feathers on both arms and legs (see Did the dinosaurs invent biplane technology?).

Senter says that long feathers of Microraptor could have interfered with the use of its hands, but he thinks it more likely the hands extended beyond the feathers.

Journal reference: Journal of Vertebrate Paleontology (vol 26, p 897)

Related Articles

Did the dinosaurs invent biplane technology?
http://www.newscientist.com/article.ns?id=dn11007
22 January 2007

Europe's largest dinosaur unearthed in Spain
http://www.newscientist.com/article.ns?id=dn10843
21 December 2006

Dinosaurs suffered climate change too
http://www.newscientist.com/article.ns? ... 125714.700
03 October 2006

Weblinks

Bambiraptor exhibit
http://www.amnh.org/exhibitions/dinosau ... raptor.php

Dromeosaurs
http://www.ucmp.berkeley.edu/diapsids/s ... ridae.html

Journal of Vertebrate Paleontology
http://www.vertpaleo.org/jvp/index.html



www.newscientist.com/article/dn11047-bi ... ngers.html

 

[ramonmercado]

Dinosaur Eggs Reportedly Found in India

edit to fix link.

Fossilized eggs of dinosaurs are shown to media persons at Mandav, around 280 kilometers (175 miles) west of Bhopal, India, Monday, Feb. 5, 2007. Explorers have stumbled upon more than 100 fossilized eggs of dinosaurs belonging to the Cretaceous Era (approximately 144 to 65 million years ago), in Kukshi-Bagh area of Dhar district, of Madhya Pradesh according to a newspaper report. (AP Photo)


(AP) -- Three Indian explorers have recovered more than 100 fossilized eggs of dinosaurs in a remote area in a central Indian state, a news report said Monday.

The amateurs also found footprints of the dinosaurs through which they could also trace the 'track way' of the now extinct heavy animals, The Hindustan Times Web site quoted Vishal Verma, one of them, as saying.

All the eggs were discovered from a single nesting site in Kukshi-Bagh area, some 95 miles southwest of Indore, a key city of Madhya Pradesh state.

"These animals used to come from far away areas to lay eggs on the sandy banks of the rivers in this area, identified scientifically as Lameta bed," Verma said.

The dinosaurs were 40-90 feet in length, Verma said. The richest dinosaur field in India is in the "Deccan Traps" near Jabalpur, a town also in Madhya Pradesh state.

http://www.physorg.com/printnews.php?newsid=89987247

 

[LaurenChurchill]

Does nyone else think it's stupid of scientists to make a definite claim regarding dino eating habits based on those of ostriches?
I understand that birds are dinosaurs closest relatives but the key word there is RELATIVES. As in, not dinosaurs but similar. If they look different and eat different things and ARE different (though similar) surely you can't make definite claims. The most you could get from it is an indication of how you should be looking at something.
Sorry to rant and if I didn't make sense, don't worry. It just shits me when people pretend they know more than they do

 

[Hanslune]

I believe the scientists said, "they believed" that is not a definitive statement of fact but the offering up of an idea.

 

[ramonmercado]

Museum IDs New Species of Dinosaur



This two image combination provided Saturday, March 3, 2007 by the Cleveland Museum of Natural History shows, at top, a photo of the skull of the new horned dinosaur, Albertaceratops nesmoi, and at bottom, an artist's reconstruction of the skull. Michael Ryan, curator of vertebrate paleontology for the Cleveland Museum of Natural History, published the discovery of the dinosaur in the March 2007 Journal of Paleontology. He dug up the fossil six years ago in southern Alberta, Canada, while a graduate student for the University of Calgary. (AP Photo/Cleveland Museum of Natural History, artist\'s rendering by Donna Sloan/Royal Tyrrell Museum of Paleontology, photo courtesy Michael J Ryan and the RTMP)


(AP) -- A new dinosaur species was a plant-eater with yard-long horns over its eyebrows, suggesting an evolutionary middle step between older dinosaurs with even larger horns and the small-horned creatures that followed, experts said.

The dinosaur's horns, thick as a human arm, are like those of triceratops - which came 10 million years later. However, this animal belonged to a subfamily that usually had bony nubbins a few inches long above their eyes.

Michael Ryan, curator of vertebrate paleontology for the Cleveland Museum of Natural History, published the discovery in this month's Journal of Paleontology. He dug up the fossil six years ago in southern Alberta, Canada, while a graduate student for the University of Calgary.

"Unquestionably, it's an important find," said Peter Dodson, a University of Pennsylvania paleontologist. "It was sort of the grandfather or great-uncle of the really diverse horned dinosaurs that came after it."

Ryan named the new dinosaur Albertaceratops nesmoi, after the region and Cecil Nesmo, a rancher near Manyberries, Alberta, who has helped fossil hunters.

The creature was about 20 feet long and lived 78 million years ago.

The oldest known horned dinosaur in North America is called Zuniceratops. It lived 12 million years before Ryan's find, and also had large horns.

That makes the newly found creature an intermediate between older forms with large horns and later small-horned relatives, said State of Utah paleontologist Jim Kirkland, who with Douglas Wolfe identified Zuniceratops in New Mexico in 1998. He predicted then that something like Ryan's find would turn up.

"Lo and behold, evolutionary theory actually works," he said.

---

On the Net:

Cleveland Museum: http://www.cmnh.org/

Southern Alberta Dinosaur Research: http://www.dinoresearch.ca/


http://www.physorg.com/news92197298.html

 

[ramonmercado]

Published online: 7 March 2007; | doi:10.1038/news070305-6

Did a 'light' genome help birds take flight?
A smaller genome evolved in dinosaurs, long before birds learned to fly.
Lucy Odling-Smee

Tyrannosaurus rex may have had the genetic 'lightness' to permit flight, long before their descendents took to the skies.

NHPA

A study of dinosaur genomes hints that the early evolution of a smaller genome might have been necessary for later vertebrates to take to the skies.

Birds have long been known to have much smaller genomes than mammals and reptiles living on the ground. And a small genome has been linked to both small cell size and high metabolic rate: the lower volume-to-surface ratio of small cells, which don't have much DNA to pack inside, can allow for faster transport of nutrients and signals across the membrane. Thus, some suggest that the energetic demands of flight require birds to have a 'light' genome.

But which came first: flying birds or the smaller genome?

To find out, Chris Organ from Harvard University in Cambridge, Massachusetts, and his colleagues estimated the genome sizes of the dinosaur ancestors of birds.

To get genetic information out of fossils that are hundreds of millions of years old, the team looked at the size of the bone cells. First, they established the relationship between the size of the bone cells and that of the genome in 26 living species of vertebrate, from fish to birds. Using sections of fossilized bone, they then measured the size of the pockets in which the bone cells would have sat in 31 species of extinct land-bound dinosaurs. From that they could estimate the size of the bone cells and, therefore, the size of the dinosaurs' genomes.

This innovative approach "opens a lot of doors for new research" says vertebrate palaeontologist Peter Makovicky at the Field Museum in Chicago, Illinois.

The team's results show that dinosaur genomes shrank dramatically within the saurischian lineage some 60 million years before the first birds evolved, says Andrew Shedlock, also from Harvard University and a co-author of the study — published in this week's Nature1. It seems that great beasts such as Tyrannosaurus rex may at least have had the genetic 'lightness' to permit energetically demanding flight, long before their descendents took to the skies.

Stripped down for flight

It's hard to tell exactly when the genome began to shrink. The authors pin it down to a broad period between 250 and 230 million years ago. But the dinosaur fossil record is spotty, and not all fossils have been sliced up for study, notes Makovicky. "But the overall result — that a change in genome size preceded the evolution of birds — looks pretty solid," he says.

The authors also found that the DNA of living vertebrates hints that the flying species have simply lost a lot of the repetitive sequences in their genome. They speculate that an active process of chopping out baggage DNA might be needed to keep the genome trim.

Although the study suggests that small genomes came before flight evolved in birds, it also seems to be true that flying keeps cells and genomes small. Modern birds that have adopted a more sedentary lifestyle, such as ostriches, have larger genomes than strong fliers. Perhaps the active process of chucking out redundant DNA was no longer selected for in these animals. An interesting next step would be to look at the genome sizes of the flying dinosaurs, the pterosaurs, which evolved flight independently of birds, says Organ.

Quite a few traits once thought to have evolved in birds — including feathers, nesting and parental care — have now been shown to have originated in dinosaurs, long before birds arrived on the scene.

Visit our newsblog to read and post comments about this story.



References
Organ C. L., et al. Nature, 446 . 180 - 184 (2007). | Article |

http://www.nature.com/news/2007/070305/ ... 305-6.html

 

[rynner2]

Dinosaurs' den unearths new theory on extinction
ANGUS HOWARTH

SCIENTISTS have unveiled the first evidence of burrowing dinosaurs.

A set of fossils 95 million years old, described for the first time in a report in the journal Proceedings of The Royal Society, reveals the existence of a previously unknown type of dinosaur that made a snug home in the ground.

They comprise the preserved remains of a dinosaur family, found in an underground den in Montana in the US.

They are the first burrowing dinosaurs ever discovered. Scientists say the 2.1 metre-long lizard would have raised its young in burrows and used them to shelter from extreme weather, so they could live in harsh environments such as the Arctic regions and deserts.

The find also casts doubt on the theory that a giant asteroid from space that crashed into the earth wiped out the dinosaurs.

It is thought that dinosaurs died out because they did not have shelter, unlike burrowing creatures that survived past the Cretaceous age, but according to this assumption, the burrowing dinosaur should also have survived - yet it has not been found after the period the asteroid is thought to have hit Earth. :shock:

Named Oryctodromeus cubicularis, which translates as "digging runner of the den", the dinosaur, a herbivore, was ideally adapted to its life in the Cretaceous period.

Its snout was shovel-shaped to help it shift earth, while large bony shoulders provided attachments for powerful muscles used to burrow, and a strengthened hip helped to brace the creature during digging.

The fossils of an adult and two juvenile dinosaurs were found in a two-metre-long burrow with a large chamber..

The bones are from an adult, 2.1 metres long, and two 1.3-metre-long youngsters, which suggests a strong family bond, say scientists.

Dr David Varricchio, of Montana State University, who led the research, said: "The discovery uniquely preserves both an adult-young association and direct evidence of denning in the form of a dwelling trace.

"Although growth rates were probably fast, the large size of the juveniles suggests that the parent-young bond persisted for a minimum of several months."

However, the discovery may lead to confusion among scientists, as Dr Varricchio claims it raises questions about the theory of dinosaur extinction.

He continued: "By denning, small dinosaurs could have potentially withstood severe conditions, such as aridity, drought and daily or seasonal temperature extremes.

"Such behaviour would have allowed dinosaurs to occupy high mountains, desert environments and polar regions.

"Survivability of terrestrial vertebrates at the end- Cretaceous event has been attributed to sheltering behaviour, with the extinction of non-avian dinosaurs resulting from their inability to find an appropriate cover.

"Burrowing dinosaurs would challenge this argument, but these are yet to be found in the latest Cretaceous formations," Dr Varricchio said.

http://news.scotsman.com/international.cfm?id=436532007

The section I highlighted seems to me to be quite ridiculous.

The idea that a shallow burrow would protect these creatures (even assuming they were in it at the time) from asteroid impact is pretty speculative. Even if a few did survive the impact this way, what would they live on afterwards, if most other life has been blasted away?

Since this is the only example of this species to be found so far, it seems pointless to generalise about why no other fossils have been found in other geological periods.

 

[ramonmercado]

Published online: 21 March 2007; | doi:10.1038/news070319-5

Burrowing dinosaur unearthed
Fossilized family broadens picture of extinct reptiles.
John Whitfield



An artist's impression shows the "digging runner of the lair" had a broad snout for burrowing.

Lee Hall

The discovery of a dinosaur family fossilized in its burrow could make us rethink where the animals lived, how they behaved, and even what wiped them out, say researchers.

David Varricchio of Montana State University in Bozeman and his colleagues found the jumbled remains of two juveniles and an adult together in what looks to be the remains of a custom-built hole in southern Montana.

The discovery provides the first evidence that dinosaurs could burrow, and the best evidence yet for long-term parental care in dinosaurs, says team member Anthony Martin, an expert in animal traces at Emory University in Atlanta, Georgia. "I imagine that two juveniles curled up in a small space with an adult," he says.

The team has named the beast Oryctodromeus cubicularis, meaning 'digging runner of the lair'. It belongs to a group of small herbivorous dinosaurs, and lived 95 million years ago during the mid-Cretaceous period.

The skeletons are incomplete, but they show that when fully grown, the animal was about 2.1 metres long, of which more than half was tail. The dinosaur had a broad snout and powerful shoulders well adapted for digging, and sturdy hips that would help it to brace itself as it dug. It could also run on its back legs.

Secret entrance

The burrow's presence was betrayed by a patch of rock that differed from its surroundings, in an area known to contain dinosaur fossils. The burrow seems to have been dug on the edge of a river flood plain and filled with mud during a flood, burying its occupants, the researchers report in Proceedings of the Royal Society1.




Dig this: an adult Oryctodromeus cubicularis (far left) was probably 2.1 metres long.

Lee Hall

The den was just over two metres long, with a pronounced s-bend — making it harder for predators to enter — opening out into a terminal chamber. The close fit between the sizes of burrow and beast convinced the team that Oryctodromeus had dug its own den, rather than simply displacing a previous occupant. "It's not just a random attempt," says Martin. "It's very well constructed."

"It was generally assumed that dinosaurs wouldn't dig — they tend to be either runners or very large," says palaeontologist Paul Barrett of the Natural History Museum, London. "This is quite a departure."

Varricchio and his colleagues had previously found what seemed to be a family of dinosaurs in what could have been a collapsed burrow in China (see 'Fossil hints at devoted parenting in dinosaurs'), but no one had seen an actual tunnel space until now.

Safe underground

Burrowing may have helped dinosaurs to survive in harsh climates, increasing the range of habitats available to them. No one knows exactly what the environment of this part of the world was like when these dinosaurs lived there, although it was probably semi-arid.

Related dinosaurs are known to have lived in southern Australia, which was close to the South Pole at the time, and South Africa, which was hot and dry. These species and locations would be good places to look for further evidence of burrowing, says Barrett.

The lack of an ability to burrow has also been suggested as a factor in the demise of dinosaurs 65 million years ago, at the end of the Cretaceous. Many of the mammals, reptiles and amphibians that survived a mass extinction at this time could burrow, perhaps sheltering them from whatever catastrophe caused the massive cull.

"The absence of burrowing has been proposed as one reason why dinosaurs didn't make it," says Martin. "You can't use that as a reason now."

Using one specimen to speculate about the dinosaurs' extinction is "quite a big inference", says Barrett. "It might be taking the data too far," he cautions.

Visit our newsblog to read and post comments about this story.


References
Varricchio D. J., Martin A. J. & Kstsura Y. Proc. R. Soc. Lond. B, 10.1098/rspb.2006.0443 (2007).


Story from [email protected]:
http://news.nature.com//news/2007/070319/070319-5.html

 

[many_angled_one]

Casts doubt on the asteroid theory? What rubbish speculation. The existance of this *one* species of burrowing lizard can hardly cast doubt on the asteroid theory (which in any case now generally includes a period of vulcanism and such into a combined cause of mass extintion). These things when fully grown were 2.1m long, I would imagine that mass extintion of prey species would have done for them and a whole load of other species more than lack of any shelter. Maybe the ancestors of the Crocodiles ate them all? Or maybe they were just not able to adapt to the changes in climate caused by the impact?

 

[ramonmercado]

Maybe the ancestors of the Crocodiles ate them all?

I like it!

 

[rynner2]

Casts doubt on the asteroid theory? What rubbish speculation.
...............
Or maybe they were just not able to adapt to the changes in climate caused by the impact?

Since the only examples we have of this species date from 30 million years before the presumed impact, this species may have died out before then anyway. 8)

 

[ramonmercado]

Casts doubt on the asteroid theory? What rubbish speculation.
...............
Or maybe they were just not able to adapt to the changes in climate caused by the impact?

Since the only examples we have of this species date from 30 million years before the presumed impact, this species may have died out before then anyway. 8)

Alternatively they might have developed a starfaring civilisation ans escaped the asteroid impact.

 

[minkycats]

lawofnations, i know this is off topic as a response but just wanted to say i really feel bad about what has happened to your fiancee. i hope that she can continue with her work properly now that man has been dismissed from his job. all the best for the future, she sounds like a very smart woman. just sorry that she had to put up with a tutor who behaved in such a way and caused her upset.

(to all, back on topic, i love reading about dinosaurs, more please!)

over and out

minky

 

[Semyaz]

Alternatively they might have developed a starfaring civilisation ans escaped the asteroid impact.

:yeay: Lol is there any doubt. They genetically engineered the human race, before leaving in their space-craft city of Atlantis...

 

[LaurenChurchill]

Or they were all in the same place having a little party with chips and drinks and a cute little lizard cabaret when a big mean asteroid came down in just the right spot and :splat:

 

[ramonmercado]

Jurassic "Crocodile" Found in Oregon


image1

Image2

March 22, 2007—It endured a rocky ride—literally—but this ancient "sea monster" from Asia has found a place in the United States to call home.

The fossil remains of a crocodile-like reptile called Thalattosuchia have been discovered in rocks in the Blue Mountains of eastern Oregon—about 5,000 miles (8,050 kilometers) from where it most likely died, researchers announced on Monday. So far about 50 percent of the animal, including the upper leg bone and rib fragments seen here (bottom), have been unearthed.

"This creature lived in Jurassic times, so it's 150 to 180 million years old," retired University of Oregon geologist William Orr said in a press release. Orr provided expert advice to the excavation team.

"It probably lived in an area from Japan to East Timor, somewhere in the western Pacific in a tropical estuarine environment."

The reptile, the oldest ever found in Oregon, is a rare discovery in North America. But similar fossils have been found throughout Southeast Asia, so experts believe that the remains were carried to the U.S. by plate tectonics. As the section of Earth's crust containing the fossils moved eastward, the Pacific plate collided with the North American plate, pushing the bones into the mountains.

The 6- to 8-foot-long (1.8- to 2.4-meter-long) creature, shown in an artist's conception (top), is part of a group that scientists think represents an evolutionary transition for this line of crocodilians. Features from related fossils suggest that the animals were evolving from being semiaquatic to entirely ocean dwelling.

The newfound fossils will go to the University of Iowa for further study before going on display at an Oregon museum.

—Victoria Jaggard

http://news.nationalgeographic.com/news ... odile.html

 

[ramonmercado]

Golden age of dino finds forecast

Europe's "biggest dinosaur"


More details

A new "golden era" of dinosaur fossil discovery has been predicted by scientists - one which may ultimately lead to nearly 2,000 different types of the ancient reptiles being known.
With previously unexplored areas of the world now opening up for palaeontologists, new dinosaur finds are coming every week, perhaps offering further clues as to how they lived, and also how they died out.

Despite nearly 200 years of excavating dino remains, palaeontologists now believe they have literally only scratched the surface.

"When you look back at the history of palaeontology, you see eras - golden eras, we call them - and we're entering one of those now," said Paul Sereno of the University of Chicago, US.

There has been an extraordinary acceleration in the rate of discoveries around the world

Dr Paul Barrett, Natural History Museum
"We're now doing more work, on more continents, in more museums, in more laboratories, in more field areas than there has ever been in the history of the discipline - and that has created the golden era," he told BBC World Service's Discovery programme.

Surge in discoveries

The emergence of this new golden era was heralded in a recently published academic paper by Peter Dodson from the University of Pennsylvania.

Together with statistician Steve Wang, Professor Dodson created a computer model that came up with an astonishing prediction.

It estimated that the museums and research institutes in the world only hold around 30% of the dinosaur fossils that may exist - the other 70% are still in the ground.


William Buckland identified and named Megalosaurus in the 1820s
"When we submitted our study, we knew of 527 kinds of dinosaur," he said.

"Based on what has gone before, we projected into the future and found that at some point - we can't say when, but sometime in the next century or two, when we've found all the dinosaurs out there to find - the total number will be about 1,850 genres, or kinds, of dinosaur."

To work this out, the pair examined how knowledge of dinosaurs has accumulated since the first fossil find - some bones of Megalosaurus - were properly identified and described by William Buckland in 1824.

Up until 1969, the rate of discovery of new dinosaurs was around one new genus per year. From 1970, the rate of description of new kinds of dinosaurs was around six per year. And since 1990, it has risen to 15 per year.

Major announcements in 2006, for example, included Turiasaurus - Europe's largest dinosaur - and a fossil from a species of Plateosaurus that was the deepest ever found (in a drill core 2,256m below the floor of the North Sea).

Accelerating rate

Paul Barrett from the Natural History Museum in London explained that there were a number of reasons for this explosion in new discoveries.

Importantly, there are more people exploring remote and inaccessible parts of the world - and in addition there are simply more palaeontologists to do the work.

"There has been an extraordinary acceleration in the rate of discoveries around the world," he said.

"Whether that will simply continue in a nice mathematical way, as the people who wrote this study suggested, is anyone's guess.


New specimens have even revealed soft tissues for study
"They're certainly right that we haven't discovered all that we're going to discover, and that within the last five years, every year we see at least 20 new types of dinosaur appearing in the scientific literature.

"So the fact that more are going to come out seems to be pretty uncontroversial. But whether it's going to be a nice, steady progression - who knows?"

Although it is likely some fossils have simply been destroyed over time, others, buried too deep to be found by palaeontologists today, may become available to future generations when disturbed by events such as earthquakes.

And large parts of Africa, South America and Central Asia in particular remain relatively unexplored.

"As we open those up, find rocks of the right age and actually start to have a proper look, we might get a new explosion of dinosaur discoveries," Dr Barrett added

And it is hoped that there will be numerous things to find from these discoveries, including further clues as to what caused the untimely extinction of the dinosaurs 65 million years ago - the most prominent theory being that it was the result of an asteroid hitting the Earth on what is now the coast of Mexico.

"The amazing thing about the geologic record and the fossil record is that sooner or later some piece of research, some amazing find, sheds light on things that you think are absolutely unanswerable, and really changes the whole picture," said Professor Sereno.

"When the first hypothesis of the impact came about, people discarded it. Then the evidence began to pile up, and the story is not over on that yet. Slowly but surely, there are going to be more lines of evidence."

Useful discoveries

However, Luis Chiappe, curator and director of the Dinosaur Institute at the Los Angeles Natural History Museum, said that exciting as new discoveries were, what was really key was getting more fossils of well-known dinosaurs.

He would like to see new skeletons of even a well-known creature like T. rex. New specimens would give much better understanding of how it grew, how fast, the differences between females and males, and the differences between young individuals and adults.

"What a good sample of specimens will give you is more information about physiology, the general biology of a particular species," he explained.

"It is wonderful to find new dinosaurs, and every time there is a new dinosaur discovered - especially if it's a spectacular one, a big one, or a rare one - the media gets crazy, and we see it all over the place. That's great - we learn about the diversity of these animals, and that's very useful.

"But I think that it is very important that we find more and more specimens of Triceratops, T. rex, Diplodocus - animals that are very well known - because those are going to be giving us clues about how those animals worked, and how they lived."


http://news.bbc.co.uk/2/hi/science/nature/6427741.stm

 

[disgruntledgoth]

I remember, a couple of weeks ago, watching something on the feeding habits of T.Rex, with evidence that they were active hunters, and I can't find anything on it, grrrrr, I just wondered if anyone saw it and has a link to more info or anything

 

[rynner2]

cluck! cluck! cluck!

Who are you calling chicken? T. rex's closest living relative found on the farm

· Proteins sequenced from dinosaur confirm link
· Discovery ushers in new era in palaeontology

Alok Jha, science correspondent
Friday April 13, 2007
The Guardian

Scientists have at last uncovered the closest living relative of the mighty Tyrannosaurus rex, the most feared and famous of all the dinosaurs. For the first time, researchers have managed to sequence proteins from the long-extinct creature, leading them to the discovery that many of the molecules show a remarkable similarity to those of the humble chicken.
The research provides the first molecular evidence for the notion that birds are the modern-day descendants of dinosaurs, as well as overturning the long-held palaeontological assumption that delicate organic molecules such as DNA and proteins are completely destroyed during the process of fossilisation over hundreds of thousands of years. It also hints at the tantalising prospect that scientists may one day be able to emulate Jurassic Park by cloning a dinosaur.

Mary Schweitzer, a palaeontologist at North Carolina State University and the North Carolina Museum of Natural Sciences, led a team of researchers in analysing the 68m-year-old leg bone of a T-rex, recovered in 2003 in Montana. To her surprise, she found that it still contained a matrix of collagen fibres, a protein that gives bone its structure and flexibility. Working with colleagues at Harvard University Medical Centre and with the help of equipment normally used to identify and sequence tiny amounts of protein in human cancers, Prof Schweitzer managed to extract and sequence seven different T-rex proteins.

The results are published today in a series of papers in the journal Science.

"The analysis shows that T-rex collagen makeup is almost identical to that of a modern chicken - this corroborates a huge body of evidence from the fossil record that demonstrates birds are descended from meat-eating dinosaurs," said Angela Milner, the associate keeper of palaeontology at the Natural History Museum in London. "So, it is very satisfying that the molecules have provided a positive test for the morphology."

Prof Schweitzer had already sequenced protein from a woolly mammoth in 2002, but that material was from fossils that were merely 300,000 years old.

When the 68m-year-old T-rex's proteins had been isolated from the surrounding dust and rock, Prof Schweitzer's team compared them with the known proteins in living animals.

"Out of seven sequences, we had three that matched chicken uniquely and we had another that matched frogs uniquely and another that also matched newt uniquely and a couple of others that matched multiple organisms that include chickens and newts," said John Asara of the Beth Israel Deaconess Medical Centre in Boston, one of the authors of the study.

Dr Asara said the results supported the view that birds evolved from dinosaurs, but added: "If we had more species in the database to compare it to, such as alligator or crocodile, which have not been sequenced yet, we may also find matches to those species. Based on this study, it looks like chickens might be the closest amongst all species that are present in today's genome databases."

Molecular information like this can help to build better evolutionary family trees between extinct and living organisms. "The fact that identifiable proteins and amino acids can be recovered from at least some fossil vertebrates has opened up an exciting new field of investigation that may tell us more about the patterns and rates of evolution from the past to the present. And we can now do it from molecules as well as bones," said Dr Milner.

But Jack Horner of Montana State University said that sequencing the T-rex protein would also lead to a new era in palaeontology, which has so far relied on looking at the shapes and sizes of fossil bones to infer the relationships between extinct animals. The important thing was to find well-preserved material that had been protected from water and air. "To get specimens like that requires enormous amounts of material, getting specimens that are covered in tens of feet of rock."

Lewis Cantley, a biologist at Harvard University who took part in the analysis of the T-rex's proteins, said the techniques used had pushed medical technology to its limits. "The exciting thing is that this technology is still in its infancy, we're going to see it get a lot better. The machines are improving, the software is improving and there will be a lot of excitement in the palaeontology community of applying this technology to other bones that are preserved."

However, Dr Milner counselled against indulging in Jurassic Park fantasies just yet. "The fact that protein sequences from collagen of a T-rex have been recovered does not mean that we will be able to clone dinosaurs, despite what the makers of Jurassic Park suggest. Cloning any organism needs its DNA which carries the instructions to make a copy. DNA is not a protein, it is not a very stable molecule and it has never been recovered from any organism more than 30,000 years old."

http://www.guardian.co.uk/science/story ... 18,00.html