Science and art bring back to life 300-million-year-old specimens of a primitive reptile-like vertebrate

Date:

July 21, 2014

Source:

University of Lincoln

Summary:

Paleontologists have recreated the cranial structure of a 308-million-year-old lizard-like vertebrate that could be the earliest example of a reptile and explain the origin of all vertebrates that belong to reptiles, birds and mammals.

Continued

The trouble with turtles: Paleontology at a crossroads - via Herp Digest

By Naomi Lubick, Earth Magazine (Thank you Dr. Dawson (Plattsburgh SUNY for brining this article to my attention.)

(Go to http://www.earthmagazine.org/article/trouble-turtles-paleontology-crossroads#byline for charts and photos)

Traditional paleontological research has been upended over the past few decades, as less traditional fields, such as genomics and developmental biology, have weighed in on vertebrate evolution. Researchers have examined the lingering color elements in dinosaur feathers, the genetics of woolly mammoths, purported proteins and blood from dinosaurs, and other ancient fossil signatures using modern tools. But the question of turtle evolution has remained resistant to both traditional and novel methods.

More than 300 species of turtles exist today, but where they came from isn’t entirely clear. Turtles are the last big living vertebrate group to be placed firmly on the tree of life, and the arguments are getting messy. Three fields in particular — paleontology, developmental biology and microbiology/genomics — disagree about how, and from what, turtles may have evolved.

Traditional paleontologists have placed turtles, which are indisputably reptiles, in relation to a group of mostly extinct reptilian animals called anapsids, which don’t have holes in their skulls; however, analyses in the 1990s put turtles in the diapsid camp, which originally had two holes in their skulls, and closer to modern reptiles like snakes. Morphology places them near the group made up of lizards and birds and crocodiles.

Within that group, genomicists have found molecular data that places turtles closer to birds and crocodiles, rather than lizards and snakes. But even within genomics, there is debate.

Meanwhile, developmental biologists have figured out that turtles have very special shells, giving them unusual characteristics that might be found in the fossil record, though what that might look like remains to be seen.

All this disagreement thus leads back to paleontology. Find more fossils and you find more answers. But until that happens, what else can be done to solve the mystery of turtle evolution?

Turtles are the last big “intriguing puzzle” on the tree of life for living vertebrates, says Tyler Lyson, a paleontologist and vertebrate zoologist at the Smithsonian National Museum of Natural History. Their odd skeletal development — especially their unique armor, which incorporates the creatures’ internal skeletons into their outer shell — has made them difficult to place on a single branch of the tree of life.

“The trouble with turtles is that their morphology is so derived,” meaning their physical characteristics were most likely not present in their ancestors in anything like their present configuration, says Nicholas Crawford, a postdoctoral researcher at the California Academy of Sciences in San Francisco. Turtles have a combination of attributes that don’t seem to go together, he continues: “They’re aquatic, they have a beak, they have a shell. We can’t figure out where it goes morphologically. It looks like a snake or lizard, but DNA points to birds and crocodiles.”

Right now, scientists have several “hypotheses of what it takes to be a turtle,” says Jacqueline Moustakas-Verho, a postdoctoral researcher at the University of Helsinki, who organized a special turtle session at the 10th International Congress of Vertebrate Morphology in Barcelona last summer. In addition to the beak and shell, she ticks off the items on the list: the morphology of the ribs; the way the body wall, which is something like our abdominal wall, folds; and the presence of a ridge of special cells that runs along the carapace (the upper part of the turtle shell) and directs shell development.

Moustakas-Verho studies scutes, the polygonal shapes on turtles’ shells that look like scales but are more like fingernails growing over the bone of the shell. Some ancient turtle-like creatures have scutes, but others don’t, even some that are more recent in the fossil record.

These and other characteristics might differ in detail among modern turtle species, but could be shared more generally in ancient fossils — or not appear at all.

Researchers agree that the first recognizable species of turtles with full shells and other characteristics date to the Late Triassic period. But turtle ancestry goes back much further: The first controversial step back is to 260 million years ago during the Middle to Late Permian, when a creature called Eunotosaurus africanus walked the Earth.

Nearly a century ago, Eunotosaurus was considered a possible turtle predecessor because of its shape, but it later fell out of favor because it lacked a full shell and some other key skeletal connections. Now it is being reconsidered as a potential turtle ancestor. Credit: Tyler Lyson, NMNH.

Nearly a century ago, Eunotosaurus was welcomed as a possible turtle predecessor because of its shape. More recently, however, it fell out of favor as a potential turtle ancestor because it didn’t have a full shell and lacked some other key skeletal connections. Several years ago, Lyson began resuscitating Eunotosaurus’ reputation, using basic techniques for studying fossils that rely on the physical form, or morphology, of bones and bone structures to determine evolutionary relationships. He mapped the skeletal connections and general morphology of the fossils, and used histology, the examination of thin slices of shell and bone, to illuminate the cell structures inside, which hints at how they developed.

Lyson’s latest paper shows that, based on the location of scars on the bones, muscles present in a modern turtle also show up in Eunotosaurus. In the journal Evolution and Development last September, Lyson published details about a bone called the nuchal bone in the turtle carapace, which he and his colleagues argue is akin to the cleithrum, a bone normally found in the shoulder girdle in other vertebrates; but in the turtle’s development, it was shunted into part of the shell. This novel twist, which occurred sometime in the Early Mesozoic, allowed turtles to keep evolving with shells made of bone, Lyson and his team suggested.

Lyson recently put together a rough stepwise development (with large gaps) that maps a family tree of turtles and their ancestors through time, according to the morphological relationships that could have led to the turtle shell. He linked Eunotosaurus to Odontochelys, a partially shelled creature that looks like a turtle and lived about 40 million years later. The first Odontochelys specimens were discovered in China and reported in 2008 in Nature by researchers who think the animals were possibly ocean swimmers. While Odontochelys had a plastron — the solid bottom shell of a turtle — and a few primitive plates on its back, it did not have a turtle shell. Still, it had a turtle’s head and other structures that make it convincingly “turtle-ish,” says Scott Gilbert, a developmental biologist at Swarthmore College, who along with Moustakas-Verho coordinated the turtle session at the vertebrate meeting last year.

“These species, namely Eunotosaurus, helped bridge the morphological gap between other reptiles and turtles,” Lyson says. “The appearance of those features that are important in building a turtle shell are mirrored in the development of modern turtle embryos.”

To understand how a certain feature develops, the best place to start is at the beginning: the embryo. Paleobiologists may not be able to examine fossil embryos, but they can look to modern animals. Vertebrates share many stages of development as embryos, which means that looking at a tiny chick, alligator and even human at certain points before they hatch or are born illuminates those similarities — and where they diverge reveals where genetic changes allowed species to differentiate.

As Lyson’s undergraduate adviser at Swarthmore, Gilbert first introduced Lyson to the utility of developmental biology as an evolutionary tool. Gilbert and his colleagues used it a decade ago to overturn some of the notions of how turtle shells form.

Gilbert and his colleagues study modern embryo development in red-eared slider turtles. Once the favorite of biology teachers and popular pets for little kids, these turtles have infiltrated ecosystems everywhere from North America to Asia. They are also easily raised for lab work.

By examining red-eared slider turtle embryos, Gilbert and his colleagues showed that plates called osteoderms — which paleobiologists had previously thought grew together to form turtles’ shells — are not the way a shell begins to form. Gilbert’s team found that during development, instead of forming a well-rounded cage around the lungs, the ribs grow straight out into the dermis, as long tapered bones. Then, the researchers suggest, the spaces between the ribs fill in with dermal cells that are converted into bone.

At the vertebrate morphology meeting last year, Gilbert and Judith Cebra-Thomas of Millersville University in Pennsylvania, who are working to trace proteins that could show how skin cells develop into bone in turtle embryos, presented further evidence for how they think red-eared sliders model the development for ancient turtles with hard shells.

However, developmental biologists studying other modern turtles are finding different shell growth patterns. Researchers in Japan reported last year that in the Chinese soft-shelled turtle Pelodiscus sinensis, the rib bones, which look like small spoons, produce their own layer of cells that harden into bone, instead of dermal cells filling in the gaps. This seemingly small difference in development has implications for the evolution of turtle shell growth, and what fossilized bones might look like in species on the path to solid shells, said Shigeru Kuratani and Tatsuya Hirasawa of the RIKEN Center for Developmental Biology in Kobe, Japan, who reported their findings in Nature Communications and presented them at the meeting.

One possible source of these differences, raised by Gilbert and others, however, is that the soft-shelled turtles simply develop differently than hard-shelled ones do. Researchers at the symposium proposed studying other modern species in the same detail.

Meanwhile, Lyson has taken the work from both teams and applied it to the ancient Eunotosaurus fossils he has been studying, to look for bone formation details that would fit the developmental models provided by modern turtles. He has also turned to genetics. Modern relatives of turtles and their genes have provided clues to, but also muddied the waters of, turtle origins. In 2012, Lyson and his colleagues published an analysis of microRNA data — tiny shards of genetic material extracted from modern turtles and alligators, which they compared to chickens, lizards and other animals to see which modern species might contain a shared genetic signature, long-preserved in the descendants of a common ancestor.

The microRNA work indicates a closer relationship to the lizards and snakes. Lyson’s morphological work places Eunotosaurus in a precursor group, related to both the archosaurs and their sister clade, lepidosaurs, which includes lizards and snakes — not as an equal “sister” group, but as a related predecessor.

However, recent genomics work from Crawford and his colleagues placed turtles in a direct sister group related to birds and crocodiles (archosaurs). A team that included Kuratani also confirmed that direct relationship in a recent genome comparison between soft-shelled turtles and green sea turtles, published last year in Nature Genetics.

So far, the groups have agreed to disagree.

Using microRNA “is flawed,” Crawford says. MicroRNA is “really difficult to identify well because they are such small sequences — 20 base pairs long.” However, he says that the “molecular story” presented by most of the peer-reviewed studies, for example, using conserved elements of DNA, is consistent, pointing to the archosaurs — with the exception of the results from Lyson and his co-workers.

The concept of just how related species are (and the relatedness of clades) is the subject of cladistics, one of the original fields in paleontology. Established in the early 1950s, cladistical analyses now rely on computer modeling to determine the degree of “relatedness” of different morphological characteristics using statistical methods. (Cladistics now can feed into phylogenetics, the related genetics analysis that determines relationships by shared genetic signatures, which also feed into these clade designations.)

Olivier Rieppel of the Field Museum in Chicago published a cladistical analysis in Nature in the 1990s that recharacterized turtles, based on their morphology: Modern turtles have no holes in their skulls, similar to the extinct Paleozoic anapsids. But Rieppel and his co-author determined that turtles are more like diapsids: modern reptiles and extinct dinosaurs, with two holes in their skulls located in the temporal lobe or the forehead. Turtles’ filled-in skulls, with no “window” in the temporal lobe, were likely an evolutionary quirk, they determined. The temporal window could have been lost over time — which has implications for future fossil finds.

Rieppel says that not enough information is available now to allow for a satisfactory turtle tree using rigorous cladistics modeling. The most ancient possible turtle ancestors are just too sparse in the fossil record.

Turtles are “one of the last remaining controversies in biology between molecular and developmental morphology,” and by extension, the fossil record, Gilbert says. The evolutionary paths of other animal groups, from birds to whales, have been answered recently by different means. The controversy over turtles’ origins presents an opportunity for morphologists and paleontologists to show that structures matter as much as genomics, he says.

Answers must still come from the fossil record in the end, he and other researchers say. The ancestors of turtles could have had something that looked nothing like a shell, and yet was still a shell — just as swimming bladders in fish and lungs in mammals had the same ancestral structure, yet seem to be unalike. It will take new findings from the right time in the fossil record to confirm any new intermediary stages and the progression of turtle development.

Getting to the shelled creature we know today could have meant “two steps forward and one step back” in the evolution of some species related to turtles, says Walter Joyce, a paleobiologist at the University of Freiburg in Switzerland, who advised Lyson while both were at Yale University and who continues to work with him as a co-author.

Paleontologists “have at least a chance of actually seeing what happened in fossil evolution,” Joyce says, which a microbiologist can’t see. “We’re not superfluous, we’re also part of the debate. And typically, we actually resolve it,” he adds.

To find answers to the question of turtle origins and evolution, and where Eunotosaurus and other ancient creatures might fit in their lineage, paleontologists have looked to these multiple methods — but they have yet to give a unified view of turtle development.

Lyson readily admits that he is not a geneticist or microbiologist, which has meant teaming up with specialists around the world in a variety of disciplines who might help him find answers. Genomics in particular has crept into paleontology by way of evolutionary biology, and has probably been most responsible for upending how paleontology is practiced, he says.

Today, researchers are attempting to combine all three fields to finally place turtles in their proper place on a family tree. “If it turns out that all three are coming together in the same solution, that’s of course when we all celebrate,” Joyce says. “I would say that by now, if we have controversy, it’s because something interesting is happening” in the study of turtle evolution. But “if something interesting is happening, then what is it? It’s either the morphology is messed up, or the fossils, or the DNA are messed up. One of the three is messed up, and there has to be a reason for that. If we keep going, we’ll find the reason.”

Trove of Ancient Marsupial Fossils Discovered in Australia

Paleontologists have uncovered a fossil field in Australia that fills a large gap in the continent's environmental history, and contains several previously unknown ancient species of marsupials and bats.

Researchers at the University of New South Wales discovered the site near the Riversleigh fossil field, an UNESCO World Heritage site, in northwest Queensland last year, and have since collected nearly 4,000 lbs. (1,800 kilograms) of rock for analysis, according to a statement from the university.

Preliminary analyses suggest that the fossils formed about 13 million to 5 million years ago — a period marking Australia's transition from a warm, tropical climate to the arid climate that persists today and an epoch largely missing from the known fossil record.

Continued

High Diversity of Flying Reptiles in England 110 Million Years Ago

June 12, 2013 — Brazilian paleontologists Taissa Rodrigues, of the Federal University of Espirito Santo, and Alexander W. A. Kellner, of the National Museum of the Federal University of Rio de Janeiro, have just presented the most extensive review yet available of toothed pterosaurs from the Cretaceous of England. The study features detailed taxonomic information, diagnoses and photographs of 30 species and was published in the open access journal ZooKeys.

Pterosaurs from the Cretaceous of England were first described by British naturalists Richard Owen and Harry Seeley in the 19th century, when little was known about the diversity of the group, resulting in the description of dozens of species, all based on very fragmentary remains, represented mostly by the tips of the snouts of these animals. However, more recent findings of pterosaur fossils have challenged views on their diversity.

Results show that these pterosaurs had a remarkable diversity in their appearances. Some species had head crests of different sizes and shapes, while others had none. Most had large teeth at the tip of their snouts and were fish eaters, but others had smaller teeth, suggesting different feeding preferences. The paleontologists were able to identify fourteen different species, belonging to at least five different genera, showing a greater diversity than previously thought.

Continued

Paleontologists brought to tears, laughter by Creation Museum

By Britt Kennerly (AFP) – Jun 30, 2009 

PETERSBURG, Kentucky (AFP) — For a group of paleontologists, a tour of the Creation Museum seemed like a great tongue-in-cheek way to cap off a serious conference.

But while there were a few laughs and some clowning for the camera, most left more offended than amused by the frightening way in which evolution -- and their life's work -- was attacked.

"It's sort of a monument to scientific illiteracy, isn't it?" said Jerry Lipps, professor of geology, paleontology and evolution at University of California, Berkeley.

"Like Sunday school with statues... this is a special brand of religion here. I don't think even most mainstream Christians would believe in this interpretation of Earth's history."

The 27 million dollar, 70,000-square-foot (6,500-square-metre) museum which has been dubbed a "creationist Disneyland" has attracted 715,000 visitors since it opened in mid-2007 with a vow to "bring the pages of the Bible to life."

Its presents a literal interpretation of the Bible and argues that believing otherwise leads to moral relativism and the destruction of social values.

Creationism is a theory not supported by most mainstream Christian churches.

Lisa Park of the University of Akron cried at one point as she walked a hallway full of flashing images of war, famine and natural disasters which the museum blames on belief in evolution.

"I think it's very bad science and even worse theology -- and the theology is far more offensive to me," said Park, a professor of paleontology who is an elder in the Presbyterian Church.

"I think there's a lot of focus on fear, and I don't think that's a very Christian message... I find it a malicious manipulation of the public."

Read on

2-Ton 'Alien' Horned Dinosaur Discovered

Paleontologists in Canada have discovered fossils of a new 2-ton, 20-foot-long horned dinosaur that roamed the Earth about 80 million years ago. And its headgear would've put on quite a show for the ladies.

The dinosaur, a distant cousin of Triceratops called Xenoceratops foremostensis, is one of the oldest specimens known to date of the ceratopsid group. The beast's name, Xenoceratops, translates to "alien horned-face," referring to its strange pattern of horns on its head and above its brow, and the rarity of such horned dinosaurs in this part of the fossil record. 

"It seems to have the general types of ornamentation that we see taken to even greater extremes in later ceratopsids," said David Evans, a paleontologist at the Royal Ontario Museum. "That suggests the elaborate headgear evolved earlier." 

Continued: http://www.livescience.com/24623-alien-horned-dinosaur.html

[Paleontology • 2012] Pliosaurus funkei | 'Predator X' •

A new species of Pliosaurus(Sauropterygia: Plesiosauria) from the Middle Volgian of central Spitsbergen, Norway

http://novataxa.blogspot.co.uk/2012/10/2012-predator-x-pliosaurus-funkei.html

New Species of Ancient Rodents Hint at What Could Be World's Oldest Grasslands

ScienceDaily (July 23, 2012) — A paleontological team that includes scientists from the American Museum of Natural History; University of California, Santa Barbara; and Case Western Reserve University has described two ancient species of South American rodents, including the oldest chinchilla, a discovery that substantiates what might be the earliest grasslands in the world. The two new species lived near a chain of volcanoes about 32.5 million years ago in what are now the steep slopes of a river valley in the Chilean Andes. Studies of the teeth of the ancient chinchilla support evidence from other species in the concurrent fauna indicating that the animals inhabited an open and dry environment 15 million years before grasslands emerged elsewhere in the world.

The research is published this week in American Museum Novitates, a peer-reviewed scientific journal of the American Museum of Natural History.

"The new chinchilla fossil provides important new evidence that early rodents joined other South American mammals in evolving ways to cope with an abrasive diet long before horses, sheep and other mammal groups on other continents 'invented' similar adaptations for making their teeth wear out more slowly while eating tough grasses," said John Flynn, Frick Curator of Fossil Mammals and dean of the Richard Gilder Graduate School at the American Museum of Natural History, who is a co-author of the paper.

Continued:  http://www.sciencedaily.com/releases/2012/07/120723134749.htm

Beyond the Tyrannosaur: Other Auction Specimens Alarm Scientists

While the nearly complete tyrannosaur skeleton up for auction on Sunday (May 20) is now the subject of a legal battle, other fossils sold that day may also have been smuggled out of Mongolia, paleontologists say.

These include teeth belonging to the same species of dinosaur, a Tarbosaurus bataar, and the distinctive skull of an ankylosaurid, an armored dinosaur.

With the exception of some fragments that are difficult to definitively identify, fossils belonging to Tarbosaurus bataar (also called Tyrannosaurs bataar) have come exclusively from a single rock formation in Mongolia, a country that forbids the export of fossils.

Looting of fossils is an increasing problem in Mongolia, paleontologists say.

Continued: http://www.livescience.com/20545-auction-fossils-controversy.html

Seven New Meat-Eating Dinosaurs Found in South Eastern Australia

A team of paleontologists and volunteers has discovered remains of at least seven different killer dinosaurs that once lived in what is now south-eastern Australia.

A study, published in the journal PLoS ONE, describes the finds of scientists and volunteers from Monash University and Museum Victoria who uncovered a higher than expected biodiversity of meat-eating theropod dinosaur fossils from between 105 and 120 million years ago.

“We had not expected to find fossils from such a large range of dinosaur species in this area,” said study co-author Dr Tom Rich. “The fossils we have collected range from tiny, cat-sized killers to Australia’s version of T. Rex, a 9-meter-long predator with powerful arms and razor-sharp claws.”

The team identified up to seven theropod dinosaurs, belonging to the Ceratosauria, Spinosauridae, Tyrannosauroidea, Maniraptora, a basal coelurosaur, and possibly Ornithomimosauria, and Allosauroidea.

“In total 1500 isolated bones and teeth of various kinds of dinosaurs have been found in Victoria, Australia so far. Their meaning is only beginning to be unraveled by detailed study and comparisons with other fossils worldwide,” Dr Rich added.

At the time these dinosaurs ruled, southern Australia was part of the Antarctic Circle. Despite the cold, there was a high diversity of small predators, similar to the Velociraptor, featured in ‘Jurassic Park’.

“One of the reasons for the success of small, theropod dinosaurs may be their warm-blood. As close relatives of birds, they had feathery insulation which helped maintain high body temperatures,” Dr Rich explained.

“The cool, damp climate may also explain the discovery of the same dinosaur species in both Australia and the northern continents.”

Research leader Dr Roger Benson from the University of Cambridge said: “the study reports new discoveries and rationalizes previous investigations.”

http://www.sci-news.com/paleontology/article00323.html

20-million-year-old skull discovery

Scientists in Paris have unveiled a 20-million-year-old skull they hope will help with the study of human ancestry.

The Ugandapithecus was found in Uganda in the layers of sediment under the volcanoes of the Karamoja region.

The discovery of the skull represents the culmination of more than 25 years of work and it is the most complete skull of this type to ever be found.

Martin Pickford, one of the paleontologists who discovered the skull, said: "It's the first time we've got a real good sample of Ugandapithecus Major.

"Before that, it was known by jaw fragments, isolated teeth, a few postcranial bones. But here, we really have a good idea for the first time of what the whole skull might have looked like."

The British paleontologist said the discovery would allow scientists to fill a gap in the lineage of primates but said the Ugandapithecus could very well have become extinct without leading to the birth of man.

http://news.uk.msn.com/articles.aspx?cp-documentid=159215627

Birch Mouse Ancestor Discovered in Inner Mongolia Is New Species of Rare 'Living Fossil'

Paleontologist Yuri Kimura, Southern Methodist University in Dallas,
identified a new species of birch mice, Sicista primus, from 17 tiny teeth.
A single molar is about the size of half a grain of rice. The teeth, however,
are distinctive among the various genera of rodents known as Dipodidae.
Cusps, valleys, ridges and other distinguishing characteristics on the
surface of the teeth are identifiable through a microscope.
(Credit: Yuri Kimura/Southern Methodist University)

ScienceDaily (May 25, 2011) — Tiny fossil teeth discovered in Inner Mongolia are a new species of birch mouse, indicating that ancestors of the small rodent are much older than previously reported, according to paleontologist Yuri Kimura, Southern Methodist University in Dallas.

Fossils of the new species were discovered in sediments that are 17 million years old, said Kimura, who identified the new species and named it Sicista primus to include the Latin word for "first."

Previously the oldest prehistoric ancestor of the modern-day birch mouse was one that inhabited Inner Mongolia 8 million years ago.

Adding 9 million years to the ancestry of the rodent family that includes birch mice and jumping mice distinguishes this genus, Sicista, as a "living fossil," Kimura said. That places the genus among some of the most unique rodents on earth -- those whose ancestry spans 2 to 3 times the average, she said.

Kimura identified Sicista primus from 17 tiny teeth, whose size makes them difficult to find. A single molar is about the size of half a grain of rice. The teeth, however, are distinctive among the various genera of rodents known as Dipodidae. Cusps, valleys, ridges and other distinguishing characteristics on the surface of the teeth are identifiable through a microscope.

"We are very lucky to have these," Kimura said. "Paleontologists usually look for bones, but a mouse is very tiny and its bones are very thin and fragile. The teeth, however, are preserved by enamel. Interestingly, small mammal teeth are very diverse in terms of their structure, so from that we can identify a species."

Kimura reported the new species in the scientific journal Naturwissenschaften. Images of the research and expedition are posted on the SMU Research flickr site (http://www.flickr.com/photos/52146845@N06/sets/72157626764403486/). SMUVideo's "Inner Mongolia yields 'living fossil'" featuring Kimura discussing the research is available on YouTube (http://www.youtube.com/watch?v=khkx11WlKaw).

An SMU doctoral student in the Huffington Department of Earth Sciences, Kimura was part of the international team that discovered the fossils during expeditions to Inner Mongolia in 2004, 2005 and 2007.

Microscopic evidence of a living fossil

The new fossils of Sicista primus from the Early Miocene age are also now the earliest known record of Sicista, the birch mouse genus that comprises 13 modern and 7 fossil species, said Kimura. As a result, Sicista now boasts the most ancient ancestry of the 326 genera in the largest rodent suborder to which it belongs, Myomorpha. The suborder includes laboratory mice and rats.

"The birch mouse is a rare case of a small mammal genus persisting from the Early Miocene without significant morphological changes," Kimura said in reporting the findings.

Rodents, both modern and prehistoric, rank as the most prolific mammals on earth. After the reign of dinosaurs, 65 million years ago, rodents evolved and dispersed worldwide during the Cenozoic, the "Age of Mammals." They comprise about 42 percent of all living mammals. Scientists know now that only 1.5 percent of modern rodent genera, however, go as far back as the Early Miocene or older.

"Diversity within a rodent genus is not unusual, but the long record of the genus Sicista, first recognized at 17 million years ago, is unusual," said Kimura. "The discovery of Early Miocene S. primus reveals that Sicista is fundamental to understanding how a long-lived genus persisted among substantially fast-evolving rodent groups."

Birch mice migrated from Asia to North America

Previously the record for the oldest species of Sicista belonged to an 8 million-year-old species identified in Eurasia, Kimura said.

In identifying the new species, Kimura also reverses the long-held hypothesis that ancestors of birch mice migrated from North America to Asia. That hypothesis has been based on a 14.8 million-year-old specimen from South Dakota, which was identified in 1977 as the separate rodent genus Macrognathomys. Kimura's analysis, however, concludes that Macrognathomys is actually Sicista. For that reason, she concluded, Sicista first inhabited the forests and grasslands of prehistoric Asia and then dispersed to North America via the Bering Land Bridge, Kimura said.

In a comparison of the molars and premolars from Macrognathomys and Sicista primus, Kimura reported finding 12 shared dental characteristics. In addition, phylogenetic analysis to identify evolutionary relationships indicated that both belong to the same genus, Sicista, she said.

Reconnaissance of earlier Central Asiatic Expedition localities yields small mammals

The teeth of Sicista primus were discovered in fine sediments gathered from Gashunyinadege, a fossil locality in the central region of Inner Mongolia.

Gashunyinadege is one of several fossil localities near Tunggur, a fossil site discovered in the 1920s by the Central Asiatic Expedition, which was led by Roy Chapman Andrews from the American Museum of Natural History.

Kimura is a member of an international scientific team sponsored by the Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology and the Natural History Museum of Los Angeles County. The team's expeditions have been led by paleontologists Qiu Zhuding, IVPP; Wang Xiaoming, Natural History Museum of Los Angeles County; and Li Qiang, IVPP. Their expeditions retrace important classic localities, as well as prospect new fossil localities.

Kimura and other members of the team discovered the birch mouse fossils by first prospecting Gashunyinadege for small mammal fossils visible to the naked eye. Those fossils indicated the possibility of even smaller mammal fossils, so the team gathered 6,000 kilograms, more than 13,000 pounds, of Early Miocene sediment. Using standing water from recent rains, they washed the sediments repeatedly through continually smaller screens to separate out small fossils. Bags of concentrate containing particles the size of mouse teeth were returned to IVPP laboratories to hunt for fossils with a microscope.

The research was funded by the Institute for the Study of Earth and Man at SMU, Dallas Paleontological Society, Geological Society of America, Chinese Academy of Sciences Institute of Vertebrate Paleontology and Paleoanthropology.

http://www.sciencedaily.com/releases/2011/05/110524153420.htm

Fossil of Giant Ancient Sea Predator Discovered

Anomalocaridids had long, spiny head limbs presumably used to snag
prey, and a series of blade-like filaments in segments across the animal's
back, which scientists think might have functioned as gills.
(Credit: Esben Horn)

ScienceDaily (May 26, 2011) — Paleontologists have discovered that a group of remarkable ancient sea creatures existed for much longer and grew to much larger sizes than previously thought, thanks to extraordinarily well-preserved fossils discovered in Morocco.

The creatures, known as anomalocaridids, were already thought to be the largest animals of the Cambrian period, known for the "Cambrian Explosion" that saw the sudden appearance of all the major animal groups and the establishment of complex ecosystems about 540 to 500 million years ago. Fossils from this period suggested these marine predators grew to be about two feet long. Until now, scientists also thought these strange invertebrates -- which had long spiny head limbs presumably used to snag worms and other prey, and a circlet of plates around the mouth -- died out at the end of the Cambrian.

Now a team led by former Yale researcher Peter Van Roy (now at Ghent University in Belgium) and Derek Briggs, director of the Yale Peabody Museum of Natural History, has discovered a giant fossilized anomalocaridid that measures one meter (more than three feet) in length. The anomalocaridid fossils reveal a series of blade like filaments in each segment across the animal's back, which scientists think might have functioned as gills.

In addition, the creature dates back to the Ordovician period, a time of intense biodiversification that followed the Cambrian, meaning these animals existed for 30 million years longer than previously realized.

"The anomalocaridids are one of the most iconic groups of Cambrian animals," Briggs said. "These giant invertebrate predators and scavengers have come to symbolize the unfamiliar morphologies displayed by organisms that branched off early from lineages leading to modern marine animals, and then went extinct. Now we know that they died out much more recently than we thought."

The specimens are just part of a new trove of fossils from Morocco that includes thousands of examples of soft-bodied marine fauna dating back to the early Ordovician period, 488 to 472 million years ago. Because hard shells fossilize and are preserved more readily than soft tissue, scientists had an incomplete and biased view of the marine life that existed during the Ordovician period before the recent discoveries in Morocco. The animals found in Morocco inhabited a muddy sea floor in fairly deep water, and were trapped by sediment clouds that buried them and preserved their soft bodies.

"The new discoveries in Morocco indicate that animals characteristic of the Cambrian, such as the anomalocaridids, continued to have a considerable impact on the biodiversity and ecology of marine communities many millions of years later," Van Roy said.

The paper appears in the May 26 issue of the journal Nature.

This research was supported by a National Geographic Society Research and Exploration grant and by Yale University.

http://www.sciencedaily.com/releases/2011/05/110525131709.htm

Dinosaur named 'thunder-thighs'

23 February 2011
By Jonathan Amos, Science correspondent, BBC News

Scientists have named a new dinosaur species "thunder-thighs" because of the huge thigh muscles it would have had.

Fossil remains recovered from a quarry in Utah, US, are fragmentary but enough to tell researchers the creature must have possessed extremely powerful legs.

The new species, described in the journal Acta Palaeontologica Polonica, is a sauropod - the family of dinosaurs famous for their long necks and tails.

It could have given other animals a hefty kick, say its discoverers.

"If predators came after it, it would have been able to boot them out of the way," said Dr Mike Taylor, from University College London, UK.

The team has named its dinosaur Brontomerus mcintoshi - from Greek "bronto", meaning "thunder"; and "merós", meaning "thigh".

The fossilised bones of two specimens - an adult and a juvenile - have been dated to be about 110 million years old.

They were rescued from the Hotel Mesa Quarry in Grand County, Utah.

The site has been looted by commercial fossil-hunters and so scientists have probably been denied the full range of material from which to make their classification.

Nonetheless, those bones they do have sport tell-tale features that mark out an extraordinary species.
Chief among them is a hip-bone, called the ilium, which is unusually large in comparison to that of similar dinosaurs.

The wide, blade-shaped bone projects forward ahead of the hip socket, providing a proportionally massive area for the attachment of muscles.

"As you put the skeleton together, you can run muscles down from the hip-bone to join at the knee and that gives you a whopping thigh," Dr Taylor told BBC News.

"What's interesting is that if it were a sauropod that could move particularly fast, you would expect to see very strong muscles on the back of the leg to pull it along. But we don't; this is the opposite. It seems most likely to us that what this is about is being able to deliver a strong kick," he told BBC News.

The paleo-scientists speculate that the larger specimen in their possession is the mother of the juvenile.

The adult would have weighed about six tonnes - something like the size of a large modern elephant - and probably measured 14m in length.

At a third of the size, the juvenile would have weighed in at about 200kg - the size of a pony - and been 4.5m long.

Brontomerus was living in what geologists term the Early Cretaceous Period.

Some other marks on the fossils give additional clues to what sort of lifestyle the creature had and the environment it faced.

"The shoulder blade of Brontomerus has unusual bumps that probably mark the boundaries of muscle attachments, suggesting that Brontomerus had powerful forelimb muscles as well," explained team-member Dr Matt Wedel, from the Western University of Health Sciences in Pomona, California.

"It's possible that Brontomerus mcintoshi was more athletic than most other sauropods. It is well established that far from being swamp-bound hippo-like animals, sauropods preferred drier, upland areas; so perhaps Brontomerus lived in rough, hilly terrain and the powerful leg muscles were a sort of 'dinosaur four-wheel drive'."

The team also believes the find is significant for its position in Earth history, in that it challenges the notion that sauropods began to disappear in the Early Cretaceous.

"Because sauropods were the most abundant dinosaurs found during the Jurassic Period and the rarest during the Early Cretaceous, there's long been the perception that sauropods were successful in the Jurassic and were replaced by duckbills and horned dinosaurs in the Cretaceous," said Dr Wedel.

"In the past 20 years, however, we are finding more sauropods from the Early Cretaceous period, and the picture is changing. It now seems that sauropods may have been every bit as diverse as they were during the Jurassic, but much less abundant and so much less likely to be found."

Dr Taylor is disappointed that more of Brontomerus could not be recovered, and wonders whether larger fossil pieces are being held in some unknown private collection.

"The fossil-hunters basically pillaged this site," he told BBC News.

"They left behind broken remnants and smashed bits of bone; and in some cases they were using broken bones to hold down tarpaulins - that's really the most disgraceful aspect of it."

See video and more at:  http://www.bbc.co.uk/news/science-environment-12542664
(Submitted by Paul Vella)

New Species Of Flying Reptile Identified On BC Coast

by Staff Writers
Edmonton, Canada (SPX) Jan 17, 2011

Persistence paid off for a University of Alberta paleontology researcher, who after months of pondering the origins of a fossilized jaw bone, finally identified it as a new species of pterosaur, a flying reptile that lived 70 million years ago.

Victoria Arbour says she was stumped when the small piece of jaw bone was first pulled out of of a fossil storage cabinet in the U of A's paleontology department.

"It could have been from a dinosaur, a fish or a marine reptile," said Arbour."

Arbour, a PhD student in paleontology, says the first clue to the fossil's identify came after she compared it to known species of pterosaurs, "I found a previously published paper describing the teeth of a previously discovered pterosaur and ours was very close," said Arbour.

"The teeth of our fossil were small and set close together," said Arbour. "They reminded me of piranha teeth, designed for pecking away at meat."

That led Arbour to believe her new species, named Gwawinapterus beardi was a scavenger of the late Cretaceous.

"It had a wing span of about 3 metres and patrolled the sky and set down to feed on the leftover kills made by predator dinosaurs of the time such as Albertosaurus."

The fossil is not only a new species it's the first pterosaur of any kind to be found in British Columbia. It was found on Hornby Island, off the coast of Vancouver Island

However, Arbour says the place where the fossil was located has little to do with the actual area where the living pterosaur, was actually flying around 70 million years ago.

"In the late Cretaceous period, the B.C. coastal islands were about 2,500 kilometres to the south and part of what is now mainland, California," said Arbour.

http://www.terradaily.com/reports/New_Species_Of_Flying_Reptile_Identified_On_BC_Coast_999.html

Dead Species Can Indeed Tell Tales

January 15th, 2011, 08:57 GMT | By Tudor Vieru

Research scientists have over the years developed methods of using the fossil record for studies of the future. The analysis of extinct species is allowing them to gain more insight into how modern-day animals response to changes in their environments and ecosystems, and scientists are on it 24/7.

Paleobiologists and paleontologists basically use the same approach to teasing out the future response of ecosystems from available data as climate scientists do when determining the future of the climate from old records inscribed in ancient ices.

In a new, extensive review of the scientific literature covering the fossil record, scientists have determined that the remains of ancient creatures can be used to boost modern science in a variety of ways.

One possible application could be to assess the potential environmental impacts that events similar to ones that happened in the past could have on a modern ecosystem, habitat or on species.

Using data from Earth's distant past could also help scientists predict which species will be most vulnerable to changes in the environment. In turn, this may provide thorough guidelines for restoration efforts currently being conducted by conservationists.

The review effort was funded by the US National Science Foundation (NSF), and led by Gregory Dietl and Karl Flessa. A paper detailing the findings was published in the January issue of the scientific journal Trends in Ecology and Evolution.

Gregory Dietl is a conservation paleobiologist at the Cornell University, in Ithaca, New York, and also at the Paleontological Research Institution, whereas Karl Flessa occupies an identical position at the University of Arizona.

“Conservation paleobiologists apply the data and tools of paleontology to today's problems in biodiversity conservation,” says Dietl.

“A conservation paleobiology perspective has the unique advantage of being able to identify phenomena beyond time scales of direct observation,” he explains.

“Historically, paleontologists have focused their efforts on understanding the deep-time geological record of ancient life on Earth, but these authors turn that focus 180 degrees,” H. Richard Lane says.

“In putting the dead to work, they identify the significant impact knowledge of fossil life can have on interpreting modern biodiversity and ecological trends,” explains the expert, who is the program director of the NSF Division of Earth Sciences.

http://news.softpedia.com/news/Dead-Species-Can-Indeed-Tell-Tales-178432.shtml

Why did mammals evolve to enormous sizes - then get smaller again?

After the dinosaurs were wiped out by a massive meteor strike 65 million years ago, tiny mammals ruled the Earth. But they quickly evolved to be as big as dinosaurs, then evolved to be smaller again. What happened?


This is what paleontologists have long wondered. Scientists knew that extremely large mammals evolved within a few million years after the end of the dinosaurs. As evolutionary biologist Patrick Stephens puts it:

There is a much better fossil record for mammals than for many other groups. That's partly because mammals' teeth preserve really well. And as it happens, tooth size correlates well with overall body size.

But how many of these mammals there were, and why they evolved, have been a mystery until a group of international scientists pooled all the information they had about these giant mammals into one database.

What they discovered was extraordinary: Giant mammals, long believed to be somewhat rare, were common across the entire planet. It seems they grew to fill an ecological niche left by the dinosaurs, aided by a cooling climate and greater amounts of land mass that supported large body sizes. Even more interesting is that mammals didn't reach some "upper biomechanical limit" to their body sizes - they could have grown much larger. The only thing that prevented truly mega-mammals from evolving were climate and available food resources.

According to a summary of the research, published today in Science:

The researchers found that the pattern was indeed consistent, not only globally but across time and across trophic groups and lineages-that is, animals with differing diets and descended from different ancestors-as well. The maximum size of mammals began to increase sharply about 65 million years ago, peaking in the Oligocene Epoch (about 34 million years ago) in Eurasia, and again in the Miocene Epoch (about 10 million years ago) in Eurasia and Africa.

"Having so many different lineages independently evolve to such similar maximum sizes suggests that there were similar ecological roles to be filled by giant mammals across the globe," said [researcher John] Gittleman. "The consistency of the pattern strongly implies that biota in all regions were responding to the same ecological constraints."

Global temperature and the amount of land available as an animal's range are two ecological factors that appear to correlate with the evolution of maximum body size, but Gittleman warned against assigning cause and effect. "A big part of science is seeing patterns, and then producing new hypotheses and testing them," he said. "We have now identified this pattern very rigorously."

The point is, climate change could - over millions of years - lead to giant monsters. So there's something for future geoengineers to aspire to.

You can read more about the scientists collaborating on giant mammal work via their website, or read their paper via Science

Amazing Horned Dinosaurs Unearthed on 'Lost Continent'; New Discoveries Include Bizarre Beast With 15 Horns

Artist's rendering of two new species of dinosaur -- Utahceratops gettyi and Kosmoceratops richardsoni -- discovered in the Grand Staircase-Escalante National Monument of southern Utah.
(Credit: Courtesy of Utah Museum of Natural History)

ScienceDaily (Sep. 22, 2010) — Two remarkable new species of horned dinosaurs have been found in Grand Staircase-Escalante National Monument, southern Utah. The giant plant-eaters were inhabitants of the "lost continent" of Laramidia, formed when a shallow sea flooded the central region of North America, isolating the eastern and western portions of the continent for millions of years during the Late Cretaceous Period. 

The newly discovered dinosaurs, close relatives of the famous Triceratops, were announced in PLoS ONE, the online open-access journal produced by the Public Library of Science. 

The study, funded in large part by the Bureau of Land Management and the National Science Foundation, was led by Scott Sampson and Mark Loewen of the Utah Museum of Natural History (UMNH) and Department of Geology and Geophysics, University of Utah. Additional authors include Andrew Farke (Raymond Alf Museum), Eric Roberts (James Cook University), Joshua Smith (University of Utah), Catherine Forster (George Washington University), and Alan Titus (Grand Staircase-Escalante National Monument). 

The bigger of the two new dinosaurs, with a skull 2.3 meters (about 7 feet) long, is Utahceratops gettyi (U-tah-SARA-tops get-EE-i). The first part of the name combines the state of origin with ceratops, Greek for "horned face." The second part of the name honors Mike Getty, paleontology collections manager at the Utah Museum of Natural History and the discoverer of this animal. In addition to a large horn over the nose, Utahceratops has short and blunt eye horns that project strongly to the side rather than upward, much more like the horns of modern bison than those of Triceratops or other ceratopsians. 

Mark Loewen, one of the authors on the paper, likened Utahceratops to "a giant rhino with a ridiculously supersized head." 

Second of the new species is Kosmoceratops richardsoni (KOZ-mo-SARA-tops RICH-ard-SON-i). Here, the first part of the name refers to kosmos, Latin for "ornate," and ceratops, once again meaning "horned face." The latter part of the name honors Scott Richardson, the volunteer who discovered two skulls of this animal. Kosmoceratops also has sideways oriented eye horns, although much longer and more pointed than in Utahceratops. In all, Kosmoceratops possesses a total of 15 horns -- one over the nose, one atop each eye, one at the tip of each cheek bone, and ten across the rear margin of the bony frill -- making it the most ornate-headed dinosaur known. Scott Sampson, the paper's lead author, claimed that, "Kosmoceratops is one of the most amazing animals known, with a huge skull decorated with an assortment of bony bells and whistles." 

Although much speculation has ensued about the function of ceratopsian horns and frills -- from fighting off predators to recognizing other members of the same species or controlling body temperature -- the dominant idea today is that these features functioned first and foremost to enhance reproductive success. Sampson added, "Most of these bizarre features would have made lousy weapons to fend off predators. It's far more likely that they were used to intimidate or do battle with rivals of the same sex, as well as to attract individuals of the opposite sex." 

The dinosaurs were discovered in Grand Staircase-Escalante National Monument (GSENM), which encompasses 1.9 million acres of high desert terrain in south-central Utah. This vast and rugged region, part of the National Landscape Conservation System administered by the Bureau of Land Management, was the last major area in the lower 48 states to be formally mapped by cartographers. Today GSENM is the largest national monument in the United States. Sampson added that, "Grand Staircase-Escalante National Monument is now one of the country's last great, largely unexplored dinosaur boneyards." 

For most of the Late Cretaceous, exceptionally high sea levels flooded the low-lying portions of several continents around the world. In North America, a warm, shallow sea called the Western Interior Seaway extended from the Arctic Ocean to the Gulf of Mexico, subdividing the continent into eastern and western landmasses, known as Appalachia and Laramidia, respectively. Whereas little is known of the plants and animals that lived on Appalachia, the rocks of Laramidia exposed in the Western Interior of North America have generated a plethora of dinosaur remains. Laramidia was less than one-third the size of present day North America, approximating the area of Australia. 

Most known Laramidian dinosaurs were concentrated in a narrow belt of plains sandwiched between the seaway to the east and mountains to the west. Today, thanks to an abundant fossil record and more than a century of collecting by paleontologists, Laramidia is the best known major landmass for the entire Age of Dinosaurs, with dig sites spanning from Alaska to Mexico. Utah was located in the southern part of Laramidia, which has yielded far fewer dinosaur remains than the fossil-rich north. The world of dinosaurs was much warmer than the present day; Utahceratops and Kosmoceratops lived in a subtropical swampy environment about 100 km from the seaway. 

Beginning in the 1960's, paleontologists began to notice that the same major groups of dinosaurs seemed to be present all over this Late Cretaceous landmass, but different species of these groups occurred in the north (for example, Alberta and Montana) than in the south (New Mexico and Texas). This finding of "dinosaur provincialism" was very puzzling, given the giant body sizes of many of the dinosaurs together with the diminutive dimensions of Laramidia. Currently, there are five giant (rhino-to-elephant-sized) mammals on the entire continent of Africa. Seventy-six million years ago, there may have been more than two dozen giant dinosaurs living on a landmass about one-quarter that size. 

Mark Loewen asks, "How could so many different varieties of giant animals have co-existed on such a small chunk of real estate?" One option is that there was a greater abundance of food during the Cretaceous.

Another is that dinosaurs did not need to eat as much, perhaps because of slower metabolic rates more akin to those of modern day lizards and crocodiles than to those of mammals and birds. Whatever the factors permitting the presence of so many dinosaurs, it appears that some kind of barrier near the latitude of northern Utah and Colorado limited the exchange of dinosaur species north and south. Possibilities include physical barriers such as mountains, or climatic barriers that resulted in distinct northern and southern plant communities. Testing of these ideas have been severely hampered by a dearth of dinosaurs from the southern part of Laramidia. The new fossils from GSENM are now filling that major gap. 

During the past decade, crews from the University of Utah and several partner institutions (e.g., the Utah Geologic Survey, the Raymond Alf Museum of Paleontology, and the Bureau of Land Management) have unearthed a new assemblage of more than a dozen dinosaurs in GSENM. In addition to Utahceratops and Kosmoceratops, the collection includes a variety of other plant-eating dinosaurs -- among them duck-billed hadrosaurs, armored ankylosaurs, and dome-headed pachycephalosaurs -- together with carnivorous dinosaurs great and small, from "raptor-like" predators to mega-sized tyrannosaurs (not T. rex but rather its smaller-bodied relatives). Also recovered have been fossil plants, insect traces, clams, fishes, amphibians, lizards, turtles, crocodiles, and mammals, offering a direct glimpse into this entire ancient ecosystem. 

Most remarkable of all is that virtually every identifiable dinosaur variety found in GSENM turns out to be new to science, offering dramatic confirmation of the dinosaur provincialism hypothesis. Many of these animals are still under study, but two have been previously named: the giant duck-billed hadrosaur Gryposaurus monumentensis and the raptor-like theropod Hagryphus giganteus. 

Utahceratops and Kosmoceratops are part of a recent spate of ceratopsian dinosaur discoveries. Andrew Farke, another of the paper's authors, stated, "The past year has been a remarkable one for horned dinosaurs, with several new species named. The new Utah creatures are the icing on the cake, showing anatomy even more bizarre than typically expected for a group of animals known for its weird skulls." 

Clearly many more dinosaurs remain to be unearthed in southern Utah. "It's an exciting time to be a paleontologist," Sampson added. "With many new dinosaurs still discovered each year, we can be quite certain that plenty of surprises still await us out there." 

http://www.sciencedaily.com/releases/2010/09/100922121943.htm

Workers unearth huge fossil cache in California

21 September 2010

Workers building a substation in California have discovered 1,500 bone fragments from about 1.4 million years ago.

The fossil haul includes remains from an ancestor of the sabre-toothed tiger, large ground sloths, deer, horses, camels and numerous small rodents.

Plant matter found at the site in the arid San Timoteo Canyon, 85 miles (137km) south-east of Los Angeles, showed it was once much greener.

The bones will go on display next year.

The find is a million years older than the famous haul from the tar pits at Rancho La Brea in Los Angeles, said Rick Greenwood, a microbiologist and also director of corporate environment health and safety for Southern California Edison.

"If you step back, this is just a huge find," he said. "Everyone talks about the La Brea Tar Pits, but I think this is going to be much larger in terms of its scientific value to the research community."

The number of skeletons found at the site may be explained by a marsh or lake bed that trapped animals looking for water, leaving them victim to predators, palaeontologists think.

Tom Demere, a San Diego Museum of Natural History palaeontologist, said the find was not directly comparable to La Brea, as it comprised different species from another era.

But he said it would be valuable.

"We have a fuzzy view of what this time period was like in terms of mammal evolution," Mr Demere said. "A discovery like this - when they're all found together and in a whole range of sizes - could really be an important contribution."

http://www.bbc.co.uk/news/world-us-canada-11383757

New dinosaur species found in China

Beijing, Aug 29: Scientists in China have identified a new species of dinosaur in a mountainous region in Shandong province, experts from the Chinese Academy of Sciences (CAS) said.

Though fossils of the dinosaur were unearthed in January 2008 in Zhucheng city, where several Cretaceous dinosaurs have been found since the 1960s, they were "identified only quite recently", Xu Xing, a dinosaur researcher, was quoted as saying by Xinhua.

Xu, a researcher with CAS Institute of Vertebrate Paleontology and Paleoanthropology, has named it "Sinoceratops zhuchengensis", a type that has never been found before.

"Its skull is at least 180 cm long and 105 cm wide," said Xu. "It has a 30-cm long horn on its face and at least 10 crooked, smaller horns on the top of its head."

Ceratops (meaning "horn face") were large, plant-eating dinosaurs of the late Cretaceous period that dates back to more than 65 million years. The most renowned ceratops is the triceratops, a huge herbivore weighing over 10 tonnes.

The discovery of the new species might rewrite current theories on the morphological transition among dinosaurs, Xu said.

"It blurs the distinctions between two types of ceratops," he said. "It bears features of centrosaurus, a group of ceratops, that are smaller in size, but its size resembles chasmosaurus, the giants of ceratops."

Before the discovery in China, ceratops had been unearthed only in the western regions of North America.

http://www.newkerala.com/news2/fullnews-30479.html