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Dinosaur news
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http://www3.imperial.ac.uk/newseventsima...e_id=26465
Scientists reveal the body weight of the world's most complete Stegosaurus by Colin Smith 04 March 2015 *This image is copyright of its original author Scientists have discovered that a 150 million year old Stegosaurus stenops specimen would have been similar in weight to a small rhino when it died. Calculating body mass in animals that have been dead for many millions of years has been difficult for scientists. There are two methods for calculating body mass. One relies on researchers taking measurements of limb bones and extrapolating body mass from a large dataset of living animals, while the other produces a 3D model of the animal and applies densities to body segments to calculate mass. However, both often have varying results. The researchers from Imperial College London and the Natural History Museum are the first to combine both methods to calculate the body mass of an extinct creature to get an accurate measurement. They used this approach on a Stegosaurus skeleton nicknamed Sophie, which was found in Wyoming in the USA in 2003. They have calculated that the Sophie would have weighed around 1,600 kg, similar in weight to a small rhino. Dr Susannah Maidment, Junior Research Fellow from the Department of Earth Science and Engineering at Imperial College London, said: “Although the Stegosaurus is something of an iconic dinosaur, scientists know very little about its biology because its fossils are surprisingly rare. We don't actually know whether Sophie was female or male, despite its nickname. When it died, Sophie was a young adult - equivalent to a human teenager. Although there is no evidence for why it died, it seems that the carcass fell into a shallow pond, where it was quickly buried, preventing other animals from scavenging it, and explaining why it is so well preserved.” Professor Paul Barrett, lead dinosaur researcher at the Natural History Museum said: “These findings identify just how important exceptionally complete specimens like this are for scientific research and collections. Now we know the weight, we can start to find out more about its metabolism, feeding requirements and the growth rates of Stegosaurus. We can also use the same techniques on other complete fossils to find out much more about the wider ecology of dinosaurs.” Dr Charlotte Brassey, palaeontologist from the Museum and lead author of the study, added: “Because this incredible specimen is so complete, we have been able to create a 3D digital model of the whole fossil and each of its 360 bones, which we can research in excellent detail without using any of the original bones. We also took the skeleton’s leg bone circumference and compared it to a modern animal of similar size, and came up with matching estimates for the dinosaur’s weight.” The scientists discovered the body mass of this dinosaur by fitting simple shapes to the digital skeleton and calculating its volume. They then converted this into body mass using data collected from similar modern animals. When compared to figures calculated using the sole method of measuring leg bone circumference in conjunction with the overall weight of various living animals, the results are in close agreement. Both techniques produced an estimate of 1600 kg and, combined, are now considered the most accurate way of measuring the body weight of nearly complete fossil skeletons. Since the stegosaur arrived at the Museum in December 2013 and before it went on permanent public display one year later, researchers created a 3D model of the skeleton by scanning, photographing and measuring each of its 360 bones. In addition to the findings in this study, the data will underpin a series of future scientific studies, which will uncover more about the unusual lives of Stegosaurus. The Stegosaurus is now part of the Museum’s collection of 80 million specimens, of which eight million are fossils. The research is published today in the journal Biology Letters. *Adapted from press release issued by the Natural History Museum.
http://www.sciencedaily.com/releases/201...160506.htm
Long-necked 'dragon' discovered in China: Dinosaur's lightweight neck spanned half the length of its body Date: January 28, 2015 Source: University of Alberta Summary: Paleontologists have discovered a new species of a long-necked dinosaur from a skeleton found in China. The new species belongs to a group of dinosaurs called mamenchisaurids, known for their extremely long necks sometimes measuring up to half the length of their bodies. Most sauropods, or long-necked dinosaurs, have necks only about one third the length of their bodies.  *This image is copyright of its original author University of Alberta paleontologists including PhD student Tetsuto Miyashita, former MSc student Lida Xing and professor Philip Currie have discovered a new species of a long-necked dinosaur from a skeleton found in China. The findings have been published in a new paper in the Journal of Vertebrate Paleontology. Qijianglong (pronounced "CHI-jyang-lon") is about 15 metres in length and lived about 160 million years ago in the Late Jurassic. The name means "dragon of Qijiang," for its discovery near Qijiang City, close to Chongqing. The fossil site was found by construction workers in 2006, and the digging eventually hit a series of large neck vertebrae stretched out in the ground. Incredibly, the head of the dinosaur was still attached. "It is rare to find a head and neck of a long-necked dinosaur together because the head is so small and easily detached after the animal dies," explains Miyashita. The new species belongs to a group of dinosaurs called mamenchisaurids, known for their extremely long necks sometimes measuring up to half the length of their bodies. Most sauropods, or long-necked dinosaurs, have necks only about one third the length of their bodies. Unique among mamenchisaurids, Qijianglong had neck vertebrae that were filled with air, making their necks relatively lightweight despite their enormous size. Interlocking joints between the vertebrae also indicate a surprisingly stiff neck that was much more mobile bending vertically than sideways, similar to a construction crane. "Qijianglong is a cool animal. If you imagine a big animal that is half-neck, you can see that evolution can do quite extraordinary things." says Miyashita. Mamenchisaurids are only found in Asia, but the discovery of Qijianglong reveals that there could be as many differences among mamenchisaurids as there are between long-necked dinosaurs from different continents. "Qijianglong shows that long-necked dinosaurs diversified in unique ways in Asia during Jurassic times--something very special was going on in that continent," says Miyashita. "Nowhere else we can find dinosaurs with longer necks than those in China. The new dinosaur tells us that these extreme species thrived in isolation from the rest of the world." Miyashita believes that mamenchisaurids evolved into many different forms when other long-necked dinosaurs went extinct in Asia. "It is still a mystery why mamenchisaurids did not migrate to other continents," he says. It is possible that the dinosaurs were once isolated as a result of a large barrier such as a sea, and lost in competition with invading species when the land connection was restored later. The Qijianglong skeleton is now housed in a local museum in Qijiang. "China is home to the ancient myths of dragons," says Miyashita, "I wonder if the ancient Chinese stumbled upon a skeleton of a long-necked dinosaur like Qijianglong and pictured that mythical creature." The paper (not sure how long the publisher will give free access, so I'd save it ASAP): http://www.tandfonline.com/doi/pdf/10.10...014.889701 
Im not sure if this is "dinosaur" related, but I have a question about vegatation.
Do we know of the types of Trees that existed back then? I assume they where massive since the animals adapted such large necks and bodies to eat them, I guess they must have grown to giant sizes. I know the radiation in prehistoric times was apparently very strong and humans couldn't survive back then, but I wonder if it contributed to these massive animals and plants. I don't know nearly enough about the topic, but I'm sure a few of you do. Just strikes my interest.
Not exactly dinosaurs, but for ease of access, I'll post this here.
Scientists Discover Two Giant New Late-Triassic Creatures By Sarah Pruitt Paleontologists in both Portugal and North Carolina announced within the last week that they have discovered fossils belonging to two newly identified species. Both lived during the Late Triassic period, some 220 to 230 million years ago, when a supercontinent known as Pangaea incorporated nearly all of the land masses on Earth. In what became the Algarve region of Portugal, an enormous salamander-like creature with a broad head and thin legs roamed the tropical landscape. Around the same time, an intimidating crocodile ancestor that scientists have dubbed the “Carolina Butcher” prowled the warm, humid environs of what is now North Carolina.  *This image is copyright of its original author A reconstruction of the recently-discovered Carnufex carolinensis. (Credit: Jorge Gonzales) Scientists recently uncovered the fossilized bones of a human-sized salamander-like creature dating to the Late Triassic period (some 220 to 230 million years ago) in the Algarve, Portugal’s southernmost region. They dubbed the newly identified species Metoposaurus algarvensis, in honor of its origins. According to the scientists’ findings, the giant amphibian may have been more than 6 feet long and weighed over 200 pounds. In addition to a broad, round head, it appears to have had thin legs that may have barely supported its body weight when it was out of water.  *This image is copyright of its original author An artist’s impression of Metoposaurus algarvensis, discovered by researchers from the University of Edinburgh (Credit: University of Edinburgh/PA) Bones belonging to different species of the genus Metoposaurus, or “front lizard,” have been discovered in other regions of Europe, as well as in North America, India and Africa, but these are the first to be found on the Iberian Peninsula. According to the new study, published this week in the Journal of Vertebrate Paleontology, the widely dispersed nature of the bones suggests that metoposaurs were widespread before Pangaea split apart some 200 million years ago to form the modern continents. The study’s authors also point out that metoposaur remains have often been found in large groups, suggesting mass death due to the drying up of a lake or other habitat. Also around 230 million years ago, the newly identified reptile species Carnufex carolinensis—a massive, carnivorous ancestor of the modern crocodile—perched atop the food chain in its own part of Pangaea. At the time, just before the supercontinent began to split apart, the region that is now North Carolina was located near the equator, and the climate was also warm and wet. Paleontologists from North Carolina State University and the North Carolina Museum of Natural Sciences discovered parts of the skull, spine and arm bone of the creature while digging in the Pekin Formation in Chatham County, North Carolina. They immediately identified it as something new, noting the unique texture of the bones. “It has really pronounced ornamentation on the skull, it has all these pits and grooves,” lead study author Lindsay Zanno told LiveScience. This ornamentation is seen on today’s crocodiles, but absent in their early ancestors. Zanno and her colleagues published their findings last week in the journal Scientific Reports. They dubbed the new species Carnufex, or “butcher,” because of the creature’s long pointed skull and blade-like teeth. Measuring up to nine feet tall, it probably walked on its hind legs and used those menacing teeth to slice flesh off the bones of its victims, which may have included armored reptiles and early mammal relatives. The scientists identified the new species as an early crocodylomorph, a group that includes modern-day crocodiles, alligators and caimans, along with their extinct relatives. Carnufex was one of a number of predators fighting for supremacy in the region before the arrival of dinosaurs. Chief among these were the rauisuchids, big-headed dinosaur-like reptiles who share some skeletal features with Carnufex. At the end of the Triassic, a massive extinction claimed many of the world’s big predators, including large crocodylomorphs like Carnufex and rauisuchids. Theropods and other meat-eating dinosaurs then moved into the top predator spots, and stayed there for the next 135 million years. Meanwhile, crocodylomorphs began changing significantly in order to survive, developing smaller, sleeker bodies with longer limbs. In this way, the discovery of new species such as Carnufex helps illuminate the fact that today’s crocodylomorphs—often dubbed “living fossils” on account of their prehistoric appearance—have in fact evolved a great deal since the times of their earliest ancestors. Source: http://www.history.com/news/scientists-d...d=13099898 
Brontosaurus is back. http://www.smithsonianmag.com/science-na...92/?no-ist
It may be one of the most famous dinosaurs of all time. The trouble is that shortly after being discovered, the Jurassic creature fell into an identity crisis. The name for the long-necked, heavy-bodied herbivore Brontosaurus excelsus—the great “thunder lizard”—was tossed into the scientific wastebasket when it was discovered that the dinosaur wasn't different enough from other specimens to deserve its own distinct genus.~~But now, in a paleontological twist, Brontosaurus just might be back. A new analysis of dinosaur skeletons across multiple related species suggests that the original thunder lizard is actually unique enough to resurrect the beloved moniker, according to researchers in the U.K. and Portugal.~~“We didn’t expect this at all at the beginning,” says study co-author Emmanuel Tschopp of the Universidade Nova de Lisboa. At first, Tschopp had been working only with Octávio Mateus of the Museu da Lourinhã to update the family tree of diplodocid dinosaurs. ~~ But when it started looking like Brontosaurus might be real after all, they asked Roger Benson at the University of Oxford to join their team and run a statistical analysis on their findings. “Roger’s calculations gave the same results,” Tschopp says. “Brontosaurus should be valid.”The name Brontosaurus excelsus was coined by Yale paleontologist Othniel Charles Marsh, who described the species in an 1879 paper with the mundane title “Notice of New Jurassic Reptiles.” His description is based on an enormous partial skeleton exhumed from the 150-million-year-old rock of Como Bluff, Wyoming. This “monster” of a dinosaur added to Marsh’s rapidly growing fossil collection, which already included similar species. Just two years earlier, Marsh had named Apatosaurus ajax—the “deceptive lizard”—from a partial skeleton found in the Jurassic rock of Colorado.Brontosaurus quickly gained fame because it was among the first dinosaurs the public encountered. An illustration of its skeleton “was the first dinosaur restoration to get a wide circulation,” points out North Carolina Museum of Natural Sciences historian Paul Brinkman. This “helped spread the popularity of Brontosaurus in an era before dinosaurs proliferated widely in natural history museums.” And once museums started to put up skeletons of Brontosaurus—the first was assembled in New York City in 1905—the dinosaur’s popularity only grew. ~~ But as anyone who has strolled through an up-to-date museum hall knows, the name Brontosaurus was eventually abandoned. In 1903, paleontologist Elmer Riggs found that most of the traits that seemed to distinguish Marsh's two specimens had to do with differences in growth, and it was more likely that the skeletons belonged to the same genus. Since it was named first, Apatosaurus had priority over Brontosaurus. Despite the extreme similarity between Marsh’s skeletons, Riggs recognized that they differed just enough to be regarded as different species. Therefore Apatosaurus ajax would remain in place, and Brontosaurus was changed to Apatosaurus excelsus. It took a while for museums to follow suit, but by the 1970s everyone finally got on board with the shift.Bringing Brontosaurus back from scientific obsolescence would be the equivalent of restoring Pluto to the status of planet. And much like the drawn-out debate over the extraterrestrial body, the status of Brontosaurus relies on definitions and the philosophy of how scientists go about making divisions in a messy natural world.To navigate the ever-growing number of dinosaur species, paleontologists look to a discipline called cladistics. In short, scientists pore over dinosaur skeletons to score a set of subtle characteristics, such as the way a flange of bone is oriented. Computer programs sort through those traits to create a family tree based upon who shares which characteristics. However, different researchers might pick different characteristics and score them in different ways, so any single result is a hypothesis that requires verification from other researchers independently generating the same results. ~~Here’s where Brontosaurus stomps in. Tschopp and colleagues had set out to create a revised family tree of diplodocid dinosaurs—huge sauropods found from the western United States to Portugal—with a special emphasis on sorting out how many species of Diplodocus and Apatosaurus there were. The researchers scored 477 anatomical landmarks across 81 individual dinosaurs. While the general shape of the tree supported what other paleontologists had previously proposed, there was a surprise in store: The bones Marsh originally called Brontosaurus seem to stand apart from the two Apatosaurus species, the team reports today in PeerJ.~~ Most of the differences the researchers identified were subtle anatomical features, but there are some broader traits, Tschopp says. “The most obvious and visual feature would be that Apatosaurus has a wider neck than Brontosaurus,” he says, adding that despite the title “thunder lizard,” Brontosaurus was not quite as robust as Apatosaurus.These results came from two Brontosaurus skeletons: the one Marsh used to coin the name, and a second that could confidently be referred to as the same species. There are more possible Brontosaurus bones out there, and Tschopp studied many of them in preparation for the current study. But because the skeletons were incomplete, the bones popped up in various positions on the family tree. Now, with the new diplodocid tree in hand, Tschopp says he plans to take a second look at these bones to see whether they truly group with Brontosaurus or something else. What remains unclear is whether Brontosaurus is here to stay. Southern Methodist University paleontologist Louis Jacobs praises the new study. “Numerous new sauropods have been discovered and named in the last couple of decades, new techniques have been developed, and we simply have a more sophisticated understanding of sauropods now,” he says. The potential resurrection comes out of this burgeoning understanding. In short, Jacobs says, “good for them, and bully for Brontosaurus!” ~~ John Whitlock of Mount Aloysius College is more reserved. “For me the issue is how you want to define genera and species in dinosaur paleontology,” Whitlock says. Some researchers will look at this study and conclude that Brontosaurus should still be an Apatosaurus because of their close relationship, forming what paleontologists call a monophyletic group, while others will emphasize the diversity. There’s no standard rule for how such decisions should be made. “I think we are going to start seeing discussion about not only how much change is enough to split a monophyletic group but, more importantly, how do we compare characters and character states?” Whitlock says. “That's going to be a fun debate to be a part of, and I'm excited about it.”The fate of Brontosaurus now relies upon whether other paleontologists will be able to replicate the results, as well as what those researchers think about the threshold for when dinosaurs merit different names.Other dinosaurs are held in the same taxonomic tension. While some researchers recognize the slender tyrannosaur Gorgosaurus libratus as a unique genus, for example, others see it as a species of Albertosaurus. But the battle for Brontosaurus stands apart. The name has become a totem of the extinct creatures that continue to ignite our imaginations with scenes of Jurassic titans ambling over fern-carpeted floodplains. We’ve kept the name Brontosaurus alive because the hefty herbivore is an emissary to a past we can never visit, but that we can still connect to through the dinosaur’s magnificent bones. Protocol will ultimately dictate the dinosaur’s title, but in spirit if not in science, those old bones will always be Brontosaurus. Read more: http://www.smithsonianmag.com/science-na...M65BREZ.99 Give the gift of Smithsonian magazine for only $12! http://bit.ly/1cGUiGv Follow us: @SmithsonianMag on Twitter
Video of a new giant sauropod discovery. http://www.livescience.com/50944-supermassive-dinosaur-skeleton-found-over-70-percent-of-it-video.html
http://www.sci-news.com/paleontology/sci...02857.html
Dinosaurs Were Warm-Blooded, Scientist Suggests Dinosaurs were endothermic (warm-blooded) like mammals, says paleontologist Dr Michael D’Emic of Stony Brook University.  *This image is copyright of its original author In a 2014 study, a team of scientists led by Dr John Grady of the University of New Mexico suggested that non-avian dinosaur metabolism was neither endothermic nor ectothermic (cold-blooded) but an intermediate physiology termed ‘mesothermic.’ Based on his knowledge of how dinosaurs grew, Dr D’Emic re-analyzed that study, which led him to the strikingly different conclusion that dinosaurs were more like mammals than reptiles in their growth and metabolism. “The study that I re-analyzed was remarkable for its breadth – the authors compiled an unprecedented dataset on growth and metabolism from studies of hundreds of living animals. Upon re-analysis, it was apparent that dinosaurs weren’t just somewhat like living mammals in their physiology – they fit right within our understanding of what it means to be a ‘warm-blooded’ mammal,” Dr D’Emic said. He re-analyzed the 2014 study from two aspects. First, the study had scaled yearly growth rates to daily ones in order to standardize comparisons. “This is problematic, because many animals do not grow continuously throughout the year, generally slowing or pausing growth during colder, drier, or otherwise more stressful seasons,” said Dr D’Emic, author on the paper published in the journal Science. “Therefore, the previous study underestimated dinosaur growth rates by failing to account for their uneven growth. Like most animals, dinosaurs slowed or paused their growth annually, as shown by rings in their bones analogous to tree rings.” “The growth rates were especially underestimated for larger animals and animals that live in very stressful or seasonal environments – both of which characterize dinosaurs.” The second aspect of the re-analysis with the original study takes into account that dinosaurs should be statistically analyzed within the same group as living birds, which are also warm-blooded, because birds are descendants of Mesozoic dinosaurs. “Separating what we commonly think of as ‘dinosaurs’ from birds in a statistical analysis is generally inappropriate, because birds are dinosaurs – they’re just the dinosaurs that haven’t gone extinct.” “Re-analyzing the data with birds as dinosaurs lends more support that dinosaurs were warm-blooded, not occupants of a special, intermediate metabolic category.” M. D. D’Emic. 2015. Comment on “Evidence for mesothermy in dinosaurs.” Science, vol. 348, no. 6238, p. 982; doi: 10.1126/science.1260061 (05-30-2015, 11:23 PM)'tigerluver' Wrote: http://www.sci-news.com/paleontology/sci...02857.htmlMaybe they were warm blooded, maybe they were not. But being closely related to birds doesn't mean they were mammals, Birds aren't mammals so I don't really see the connection here. Is the scientist only suggesting warm blooded or that they were mammals as well, maybe I misread? My next question is in regards to this quote “The growth rates were especially underestimated for larger animals and animals that live in very stressful or seasonal environments – both of which characterize dinosaurs.” Do reptiles not show the same growth slow down during stressful seasonal environments? I know fish do, I would assume any vertebrate animal would. 
In fact, the article doesn't states anything about dinosaurs "been" mammals, but it say that they are "more like" mammals and not like reptiles. That is like say that birds are more like mammals too, but they are referring to the metabolism and growt, just that.
It is interesting that they mention non-avian dinosaurs, so they study sauropods, for example? It is know that theropods like the raptors or even T.rex do had that metabolism, but there were no previous evidence in the large sauropods, as far I know. Dr Bob Bakker said that dinosaurs should be warm blooded because they were active animals and I tend to agree with him. Certainly we will need more evidence and at this moment, I am a little rusty in the dinosaur department. [img]images/smilies/undecided.gif[/img]
Check this new draw of the three largest carnivores dinosaurs ever, with they new interpretations:
 *This image is copyright of its original author 1. Spinosaurus. 2. Giganotosaurus. 3. Tyrannosaurus. 4. Suchomimus (this is there only for comparison). Amazing, specially in the case of the Spinosaurus. [img]images/smilies/tongue.gif[/img] (05-31-2015, 09:10 PM)'GuateGojira' Wrote: Check this new draw of the three largest carnivores dinosaurs ever, with they new interpretations: Is T-Rex considered the Bulkiest? Do their weights show a distinct difference?
Definitely the mighty T.rex is the bulkiest, but overall it would weight the same than the largest Spinosaurus, which is about 9 tons.
The Giganotosaurus would weigh about 7 tons, depending of the specimen (extreme weight up to 8 tons), new studies showed that the holotype was of the same size than the largest T.rex which is slightly over 12 meters long, and the other "larger" specimen (the fragment of mandible) was not as large as previous estimations and now is put about 13 meters long or slightly more.
Meet 'Hellboy': New Spiky-Headed Dinosaur Found
A Triceratops cousin unearthed in Canada is so elaborately adorned "it blows your mind," one paleontologist says.  *This image is copyright of its original author Stubby horns over the eyes of Regaliceratops peterhewsi (pictured in an artist's imagining) reminded its discoverers of the comic book character Hellboy. ART BY JULIUS T. CSOTONYI. COURTESY OF ROYAL TYRRELL MUSEUM, DRUMHELLER, ALBERTA. By Devin Powell, National Geographic PUBLISHED JUNE 04, 2015 Triceratops has a new cousin with a devilishly good nickname: "Hellboy." Paleontologists who excavated the fossil skull of the horned beast from a steep cliff in Canada had a hell of time chipping the 600-pound (270-kilogram) specimen from the hard rock—hence its pet name. Only after freeing the fossil did the crew discover the moniker's pop culture connection. "There are these really stubby horns over the eyes that match up with the comic book character Hellboy," says study leader Caleb Brown, a paleontologist at the Royal Tyrrell Museum of Palaeontology in Alberta, Canada. Though it had much smaller horns on its brow than its iconic cousin, the newfound dinosaur boasted a sizable horn on its snout and a fabulous frill on its head. (Also see "New Big-Nosed Horned Dinosaur Found in Utah.")  *This image is copyright of its original author The frill, or bony head protrusion, of Regaliceratops is so elaborate it "blows your mind," one scientist says. PHOTOGRAPH BY SUE SABROWSKI, COURTESY ROYAL TYRRELL That crown of triangular bone spikes inspired its Latin scientific name: Regaliceratops peterhewski, the first word of which translates to "royal horned face," according to the study, published June 4 in the journal Current Biology. The second word is the name of the geologist who first spotted the fossil about a decade ago, Peter Hews. (See more bizarre dinosaurs.) "The size of these frill ornamentations blows your mind," says David Evans, a paleontologist at the Royal Ontario Museum in Canada who wasn't involved in the study. "If you found them by themselves, you'd almost think they were stegosaur plates." Fancy Headgear This latest addition to the clan of horned herbivores known as chasmosaurs lived about 68 million years ago during the Cretaceous period—just before the dinosaurs went extinct. Regaliceratops was especially showy for its time: Triceratops and other chasmosaurs from the same age tended to be conservative critters with smooth, unadorned frills. (See "New Horned Dinosaur Had a Funky Frill.") But fancy frills had been the fashion in a different lineage of horned dinosaurs that died out millions of years before Regaliceratops, the centrosaurs. Regaliceratops acquired its retro look thanks to convergent evolution, a process in which distantly related organisms independently evolve similar traits under similar conditions—such as the streamlined body shapes of ocean-dwelling sharks and dolphins. Expect the Unexpected Hellboy wasn't the first chasmosaur with extravagant headgear, either. Recent finds have turned up funky older relatives that lived alongside the centrosaurs, including the 76-million-year old Kosmoceratops. Dubbed the horniest dino in the world, Kosmoceratops boasted 15 horns and spikes on its head, including some on its forehead that curled downward like bangs. As with the tiny horn nubbins over Regaliceratops' eyes, these curly protrusions would have offered little protection against predators and instead may have been used, like peacock feathers, to attract mates. (See "'Large-Nosed Horned Face' Nasutoceratops Debuts.") As the family tree of the horned dinosaurs (the ceratopsians) continues to expand, paleontologists have learned to expect the unexpected. "Every time you think you've seen it all some new, weird ceratopsian shows up," says Nick Longrich, a paleontologist at the U.K.'s University of Bath who was not involved in the new research. (Watch video: "Dinosaurs 101.") "We're probably going to be seeing a lot more strangeness from this group in the future." http://news.nationalgeographic.com/2015/...f9751911=1
First dinosaur fossil discovered in Washington state
Date: May 20, 2015 Source: University of Washington Summary: Paleontologists have published a description of the first dinosaur fossil from Washington state. The fossil was collected along the shores of Sucia Island State Park in the San Juan Islands.  *This image is copyright of its original author The first dinosaur fossil described from Washington state (left) is a portion of a femur leg bone (full illustration right) from a theropod dinosaur. Theropods are a group of meat-eating, two-legged dinosaurs, including T. rex and Velociraptor. The fossil was discovered by Burke Museum paleontologists at Sucia Island State Park in the San Juan Islands. Credit: Illustration courtesy of PLOS ONE, modified by the Burke Museum. Burke Museum paleontologists have published a description of the first dinosaur fossil from Washington state. The fossil was collected by a Burke Museum research team along the shores of Sucia Island State Park in the San Juan Islands. Burke Museum researchers discovered the fossil while collecting ammonite fossils (a creature with a spiral shell) from a marine rock unit known as the Cedar District Formation. The researchers first noticed a small section of exposed bone on the surface of the rocks, then returned with a team of paleontologists to help excavate the fossil so it could be studied at the Burke Museum. A new study by Burke Museum Curator of Vertebrate Paleontology Dr. Christian Sidor and University of Washington graduate student Brandon Peecook describes the find in the journal PLOS ONE. The fossil is a partial left femur of a theropod dinosaur, the group of two-legged, carnivorous dinosaurs that includes Velociraptor, Tyrannosaurus rex and modern birds. The fossil is 16.7 inches long and 8.7 inches wide. Because the fossil is incomplete, paleontologists aren't able to identify the exact family or species it belonged to. However, Sidor and Peecook compared the fossil to other museums' specimens and were able to calculate that the complete femur would have been over 3 feet long -- slightly smaller than T. rex. The fossil is from the Late Cretaceous period and is approximately 80 million years old. Although incomplete, Sidor and Peecook were able to determine the femur is from a theropod dinosaur for two reasons: First, the hollow middle cavity of the bone (where marrow was present) is unique to theropods during this time period; and second, a feature on the surface of the bone (the fourth trochanter) is prominent and positioned relatively close to the hip, which is a combination of traits known only in some theropods among dinosaurs. "This fossil won't win a beauty contest," Sidor said. "But fortunately it preserves enough anatomy that we were able to compare it to other dinosaurs and be confident of its identification." "The fossil record of the West Coast is very spotty when compared to the rich record of the interior of North America," Peecook said. "This specimen, though fragmentary, gives us insight into what the West Coast was like 80 million years ago, plus it gets Washington into the dinosaur club." Washington is now the 37th state where dinosaurs have been found. Fossilized prehistoric clams were also found inside the hollow part of the bone, which indicates the dinosaur fossilized in marine rock. These additional fossils are a rare occurrence and provide scientists with a snapshot of other lifeforms that were present where the dinosaur fossilized. The accompanying fossilized clams are so well preserved that Burke paleontologists were able to identify the species, Crassatellites conradiana. These clams lived in shallow water, so it's likely the dinosaur died near the sea, was tossed by the waves, and eventually came to rest among the clams. Why have no dinosaurs been found in Washington state until now? Dinosaurs are found in rocks from the time periods in which they lived (240-66 million years ago). Washington state was mostly underwater during this period, so Washington has very little exposed rock of the right age. Because dinosaurs were land animals, it is very unusual to find dinosaur fossils in marine rocks--making this fossil a rare and lucky discovery. How did the dinosaur get to Sucia Island State Park? Eighty million years ago, the rocks that today form Sucia Island were likely deposited farther south. How much farther south is a topic of scientific debate, with locations ranging between present-day Baja California, Mexico, and Northern California. Earthquakes and other geologic forces that constantly reshape our planet moved the rocks north to their present-day location. Journal reference: http://journals.plos.org/plosone/article...ne.0127792 Article source: http://www.sciencedaily.com/releases/201...151618.htm |
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