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Most Primitive Kangaroo Ancestor Rediscovered After 30 Years in Obscurity

Thursday, April 12, 2018

Ancestors of Modern-Day Kangaroos Walked Upright on Two Feet

A handful of tiny teeth have led scientists to identify the most distant ancestor of today's kangaroos. The fossils were found in the desert heart of Australia, and then hidden away, and almost forgotten in a museum collection for over three decades. The findings are published in the Journal of Vertebrate Paleontology.

Kangaroos are icons of Australia's unique living fauna. However, their earliest ancestry is shrouded in mystery. At the beginning of the 1980's, a few enigmatic molar teeth were excavated by palaeontologists hunting for fossils around a dry salt lake in northern South Australia. The rare specimens were recognised as an ancient kangaroo ancestor, but had to wait for over 30 years before modern computer-based analyses could confirm the significance of the discovery.

Originally dubbed Palaeopotorous priscus, Latin for '[very] ancient', 'ancient rat-kangaroo', by the now eminent Australian palaeontologists Prof. Tim Flannery (University of Melbourne) and Dr Tom Rich (Museums Victoria), the importance of these remains was suggested in their first unveiling to science.

"The teeth of Palaeopotorous were initially described in 1986. Even then they were stated as representing possibly the most primitive relative of the entire modern kangaroo radiation. Yet, nobody ever evaluated this claim, and despite being occasionally mentioned in the scientific literature, they were never again examined in detail," said Dr Wendy den Boer, who studied the fossils as part of her recently awarded PhD from Uppsala University in Sweden.

"The name Palaeopotorous was established using a single molar tooth, although, eleven other anatomically very similar teeth were recovered during the expedition. None of these fossils were found in association, so it is still unclear whether we are dealing with one, or more species," said Dr Benjamin Kear, Dr den Boer's PhD supervisor and co-author on the published article. "This uncertainly means that we have had to use a complex series of analyses to assess its morphological similarity and evolutionary relationships relative to other members of the kangaroo family tree".

"Our results showed that Palaeopotorous was most similar to living rat-kangaroos, as well as some other extinct kangaroo relatives. Using information from fossils, and the DNA of living species, we were able to further determine that at around 24 million years old, Palaeopotorous is not just primitive, but likely represents the most distant forerunner of all known kangaroos, rat-kangaroos and their more ancient ancestors," said Dr den Boer.

"Palaeopotorous was about the size of a small rabbit, and probably did not hop, but would have bounded on all four legs. Nevertheless, a few bones found at the same site in central Australia indicate that the earliest kangaroos already possessed some key adaptations for hopping gaits," said Dr Kear.

Palaeopotorous lived at a time when central Australia was much wetter than it is today. Its fossils were buried in clay deposits left by a river, but these earliest kangaroo ancestors would have foraged amongst vegetation growing nearby and along the banks. The teeth of Palaeopotorous were washed into the river after death, along with the remains of many other ancient marsupials.?

UPPSALA UNIVERSITY

Source: www.eurekalert.org

Scientists Have Grown 'Dinosaur Legs' on a Chicken For The First Time

Friday, April 15, 2016

To achieve the long dinosaur-like bone, the researcher inhibited a maturation gene called Indian Hedgehog. With this suppressed, the chickens maintained their tubular fibula, which remained long and connected to the ankle like a dinosaur    Read more: http://www.dailymail.co.uk/sciencetech/article-3487977/Scientist-grow-dinosaur-leg-CHICKEN-bizarre-reverse-evolution-experiment.html#ixzz5ClNCp1gX  Follow us: @MailOnline on Twitter | DailyMail on Facebook

Whoa.

Until very recently, one of the biggest myths in science was that all dinosaurs have been extinct for the past 65 million years. But thanks to new fossil discoveries that filled in our knowledge about avian dinosaurs, we now know that only some dinosaurs went extinct following an asteroid collision with Earth - others survived and gave rise to the birds we live with today.

 

To figure out how this evolution occurred, researchers in Chile have manipulated the genes of regular chickens so they develop tubular, dinosaur-like fibulas on their lower legs - one of the two long, spine-like bones you’ll find in a drumstick.

In avian dinosaurs such as the Archaeopteryx, the fibula was a tube-shaped bone that reached all the way down to the ankle. Another bone, the tibia, grew to a similar length alongside it.

As evolution progressed through to a group of avian dinosaurs known as the Pygostylians, the fibula became shorter than the tibia, and sharper and more splinter-like towards the end, and it no longer reached the ankle.

While modern bird embryos still show signs of developing long, dinosaur-like fibulae, as they grow, these bones become shorter, thinner, and also take on the splinter-like ends of the Pygostylian bones, and never make it far enough down to the leg to connect with the ankle.

Researchers led by Joâo Botelho from the University of Chile decided to investigate how this transition from a long, tubular fibula in dinosaurs to a short, splinter-like fibula in birds actually came to be.

They achieved this by inhibiting the expression of a gene called IHH or Indian Hedgehog (seriously), which saw their chickens continue to grow the long, dinosaur-like fibulae that originated in their embryonic form. 

In doing so, the team discovered something bizarre. Regular bone development sees cell division and therefore growth halt in the shaft long before the ends stop growing, but in modern chickens, the growth of the fibula halts first at the ends. This means the fibulae of modern chickens are actively blocked from reaching the lengths of their ancient relatives’ bones.

Joâo Botelho et. al.

Publishing their observations in the journal Evolution, the researchers suggest that the early maturation of the lower end of the fibula in modern chickens is prompted by a bone in the ankle, called the calcaneum. 

"Unlike other animals, the calcaneum in bird embryos presses against the lower end of the fibula," the team explains in a press release. "They are so close, they have even been mistaken for a single element by some researchers."

The team suggests that in regular chickens, interactions between the calcaneum and the end of the fibula result in signals that are similar to the ones that prompt the bone shaft to stop growing, preventing the fibula from reaching anywhere near the ankle bone. 

But when the Indian Hedgehog gene was turned off, the calcaneum strongly expresses the gene Parathyroid-related protein (PthrP), which allows for growth at the ends of bones. This caused their chickens to grow long fibulae that connected with the ankle, just like they would in the Archaeopteryx. 

"Experimental downregulation of IHH signalling at a postmorphogenetic stage led to a tibia and fibula of equal length," the team writes in the report. "The fibula is longer than in controls and fused to the fibulare, whereas the tibia is shorter and bent."

Unfortunately, the 'dino-chickens' did not make it to the hatching stage, but the point of the research wasn't to raise them into adulthood, but to figure out the biological processes that led to the transition from dinosaur legs to modern bird legs. 

"The experiments are focused on single traits to test specific hypotheses," one of the team, Alexander Vargas, explains. "Not only do we know a great deal about bird development, but also about the dinosaur-bird transition, which is well-documented by the fossil record. This leads naturally to hypotheses on the evolution of development, that can be explored in the lab."

This isn't the first time dinosaur traits have been 'recreated' in modern chickens. Last year, the same team achieved the growth of dinosaur-like feet on their chickens, and a separate team in the US managed to grow a dinosaur-like 'beak'on its chicken embryos.

Source: www.sciencealert.com

 

 

Turns Out, Dinosaurs Probably Had Feathers. This Artist is Using Science to Draw More Accurate Pictures.

Wednesday, April 11, 2018

Contrary to classic depictions of a tyrannosaurus rex, paleoartist Gabriel Ugueto says that the massive carnivores likely were covered in small feathers on the top of their bodies. Credit: Credit: Gabriel Ugueto

What does a Tyrannosaurus rex actually look like? You might immediately think of the iconic, roaring lizard from the Jurassic Park films. But scientific illustrator Gabriel Ugueto turns to paleontology studies and fossil finds—poring over the science to accurately reimagine creatures that no longer exist today. And what he renders might surprise you.

Ugueto, a former herpetologist, is a paleoartist, or an artist that creates representations of animals that have gone extinct. He has illustrated everything from extinct marine reptiles, insects, mammals, flying pterosaurs, and—of course—dinosaurs. His work helps scientists better understand and visualize the species they study. But bringing these animals back to life takes just as much imagination as careful precision. Ugueto draws upon the latest research, looks to fossilized bones, and collaborates with researchers to get a little closer to what these animals may have looked like when they roamed Earth. His more scientifically accurate reconstructions of chubby, scaly plesiosaurs or fluffy, feathery dromaeosaurs might not match the terrifying, reptilian dinosaurs of pop culture.

More recent discoveries provide scientists and artists a new perspective on dinosaurs, Ugueto explains. “Contrary to popular media and what we’ve shown in movies, in paleoart, there is a huge renaissance to make these animals more accurate as to what they would have looked like,” Ugueto tells Science Friday.

Ugueto, profiled in the latest SciArts video, explains the challenges and wonders of his craft and breaks the stereotypes of how dinosaurs are depicted in popular media with guest host Flora Lichtman. View an animated breakdown of some of the important steps in Ugueto’s illustration process below.

It Begins With A Bone

Ugueto reconstructs a Plesiosaurus dolichodeirus using fossil information. Credit: © Gabriel Ugueto

“When I get an assignment, I first try to look at the bones,” Ugueto says. “You start with the bones and then work outward from that.”

For example, “right now, I’m reconstructing a series of birds from the Cenozoic, and a lot of those birds are just known from one bone, a thigh bone. So I have to basically reconstruct the rest of the animal knowing what it could look like based on what animals it is closely related to.”

Finding Modern Inspiration

A dromaeosaurid. Credit: © Gabriel Ugueto

Since he often receives fragments of remains or photographs of the fossils, Ugueto then tries “to see what the animal that I’m going to reconstruct was related to,” he says. “It’s very important to have reference material from modern-day animals and to be very familiar with anatomy of modern-day animals when you try to reconstruct something from the past. Because not only will it give you analogues to what they could have looked like, but also, in a way, we’re all related at the end of the day. It’s important that we are familiar with that. For dinosaurs, for example, we know that birds are dinosaurs. So they probably share a lot of things in common.”

Feather-covered dinosaurs continue to be a controversial conversation. But, scientists have evidence that many groups of non-avian dinosaurs, including several dromaeosaurs, had different types of feathers. Some suggest that certain species may have even had feathers “exactly like the feathers that you would see on a pigeon,” Ugueto says.

Fleshing Out Muscles

A shringasaurus. Credit: © Gabriel Ugueto

Understanding anatomy, like how muscles attach to bones, is important in accurately capturing different animals, Ugueto says. You can visualize how Ugueto carefully draws muscles and flesh in the illustration of a shringasaurus above.

“You definitely have to have a detailed knowledge of how muscles attach to different bones in different animals, because it’s not the same muscle attachment in mammals that it is for birds or reptiles,” he says. “After I’ve decided what position I’m going to put it in, I do a full skeletal reconstruction and then I try to see where the muscles could have attached. I continue with the reconstruction of putting skin, bones, and colors.”

Setting The Scene

A proceratosaurus. Credit: © Gabriel Ugueto

The ecological backdrop is just as essential to depict correctly as the animal itself. Here, Ugueto poses a proceratosaurus dipping for a drink of water.

A big part of the process “is thinking where the animal lived [and] at what period in time, because there are different climatic conditions at different times during the history of life. Based on suggested habits of the animal, I think about what integument or covering I’m going to use, my coloration and all that.”

Basking In The Beauty

Terrestrisuchus. Credit: © Gabriel Ugueto

“I think [scientists] all have an idea of what the animal is going to look like, because you have to remember that these are people that have been looking at these bones for a long time, much longer than I have,” Ugueto says. “They have an idea of what the animal could have looked like, but I do get this feeling that they are pleased and very happy to see the animal finally fleshed out, with flesh, and bones, and muscles, and color, and looking alive.”

“I would have loved to see it alive,” Ugueto says.

Source: www.sciencefriday.com

'Montana is a Hotbed for T. Rex,' but Researchers Unsure if Partial Dinosaur Skull is One of Them

Saturday, April 14, 2018

After being cleaned up in the lab, this fossil unearthed from Montana reveals the jaw and teeth of what could be a teenage Tyrannosaurus rex.  University of Kansas

Struggling with identity makes being a teenager tough — even for a 66-million-year-old teen.

The partial skull of a dinosaur unearthed this summer, north of the eastern Montana town of Jordan, faces just such a struggle. The teeth and bones seem to point to the discovery being from a young Tyrannosaurus rex, that huge meat-eating dinosaur that has fueled many dark dreams.

Or is the skull that of a Nanotyrannus, a smaller, more nimble species that shares similarities with T. rex?

“My gut says it’s a juvenile,” said Greg Liggett, a Bureau of Land Management paleontologist based in Billings. “It makes a lot of sense. There had to have been babies before they got big, so where are they?”

The fossil of a lower jaw and teeth was unearthed by a team from the University of Kansas this summer and is being cleaned in the school’s lab.

“It’s a pretty dramatic specimen,” Liggett said, one of only three similarly sized Nanotyrannus, or young T. rexes, ever unearthed. “So not many have been found, and we’ve been looking for 100 years.”

Heaven in Hell

Montana’s Hell Creek Formation is a hotbed for dinosaur bones. During that geologic time period 66 million years ago, tons of sediment poured into what was then a low-lying area that stretched from Saskatchewan in the north to Wyoming in the south. Captured in those massive sediment flows were duck-billed and three-horned fringed beasts.

In a 1908 article for Scribner’s Magazine, William Hornady described finding fossil remains while hunting mule deer years earlier in eastern Montana’s badlands.

“It was very evident that in the age of reptiles some gigantic species had inhabited that spot,” he wrote after being shown a fossilized skull half as large as a full-grown elephant.

After returning to New York City, he informed a colleague. In response to the report, the American Museum sent Barnum Brown to investigate.

“Mr. Brown found the remains of a new genus of gigantic reptiles — predatory and carnivorous to the utmost … in due time the world was introduced to Tyrannosaurus rex, the Tyrant Lizard, late of Hell Creek.”

And so the legend was born and continues to live on.

“Montana is a hotbed for T. rex,” said David Burnham, preparator of vertebrate paleontology at the KU Biodiversity Institute. “In fact, I call it T. rex world.”

Chance

It was Burnham who led the KU crew in 2016 that discovered the possibly young T. Rex. It was almost by accident. Suffering equipment delays on a separate dig, he sent everyone out to look for fossils.

“We started to find bones, teeth and claws,” he said. “Everyone was hyper excited. They were in soft sand. You could dig it with hand tools.”

Toward the end of what turned into a three-week exploration, Burnham spotted what he thought may be a skull. Rather than expose it to the weather and have to leave it until the following summer, he decided to wait. Encased in harder rock, once the fossil was cleaned in the lab this year, the stone revealed a set of jaws riddled with large teeth.

“We had some kind of an idea what it was, but we were confused,” he said. “We called it a mystery theropod.”

Theropods are meat-eating dinosaurs, typically the two-legged kind.

First to best

In addition to being a hotbed for T. rexes for more than 100 years, Montana’s Hell Creek Formation also yielded another first. In 1942 the Cleveland Museum unearthed a specimen in eastern Montana’s Carter County that was christened the first Nanotyrannus.

In 2001, a more complete skeleton was uncovered in Carter County, this one by the Burpee Museum of Natural History. Based on the earlier classification of the 1942 find, it was initially called a Nanotyrannus. But since then the museum has decided the skeleton is instead a teenage T. rex, only 11 years old and still growing.

A copy of the skull of the young T. rex, named Jane, is on display in the BLM office in Miles City. Archaeologist Doug Melton often asks paleontologists visiting the office for their summer dig permits what they think: Is Jane a young T. rex, or a Nanotyrannus? He’s gotten both answers.

“I really don’t have any theories,” he said. “But you would expect, since there’s a pretty good number of T. rexes that have come from Montana, that you would see an age range.”

Counting teeth

One of the factors dividing scientists is the number of teeth in the skulls of the smaller dinosaurs — there are more than the adult T. rexes. Burnham plans to study in detail the teeth of the fossil his team uncovered to possibly settle the dispute once and for all. The university has a privately-owned true baby T. rex on loan to help with the comparison.

The discovery, and what the study might reveal, has drawn a lot of attention to the University of Kansas program. Burnham had just spoken to someone from Paris on Friday and prior to that had given dozens of interviews and answered numerous emails since the discovery was made public.

“We’re pretty excited about it,” he said.

And more pieces of the unique specimen could be waiting in the same soils.

“I don’t think we’re finished digging there yet,” Burnham said. “We’ll roll the dice and hopefully get a more complete skeleton.”

Melton is convinced that out of the 10 to 15 permits his Miles City office will issue to museums at Yale, in Denver or in St. Louis for paleontological explorations next summer, those folks will find something.

“I would expect this year, once the snow melts and things start eroding again, we’ll probably by the end of the season see some spectacular things come out.”

Source: http://trib.com

Giant Triassic Ichthyosaur is One of Biggest Animals Ever

Thursday, April 12, 2018

Giant ichthyosaurs Shonisaurus. Image credit: Nobumichi Tamura.

According to a study released this week in the journal PLoS ONE, an isolated bone from the lower jaw of a prehistoric marine reptile found in Somerset, UK, belongs to one of the largest animals ever.

 

Fossil collector Paul de la Salle found the 205-million-year-old (Late Triassic epoch) specimen on the beach at Lilstock, Somerset, in May 2016.

Paleontologists Dean Lomax from the University of Manchester and Professor Judy Massare of SUNY College at Brockport identified it as an incomplete bone — called a surangular — from the lower jaw of a giant ichthyosaur.

The researchers estimate the length of this specimen’s body would have been up to 85 feet (26 m) — almost the size of a blue whale.

They also compared the specimen with several ichthyosaur species, including the largest ichthyosaur known — the shastasaurid Shonisaurus sikanniensis, which is 69 feet (21 m) long.

They found similarities between the new specimen and Shonisaurus sikanniensis which suggest the Lilstock bone belongs to a giant shastasaurid-like ichthyosaur.

“As the specimen is represented only by a large piece of jaw, it is difficult to provide a size estimate, but by using a simple scaling factor and comparing the same bone in Shonisaurus sikanniensis, the Lilstock specimen is about 25% larger,” the paleontologists said.

Other comparisons suggest the Lilstock ichthyosaur was at least 65-82 feet (20-25 m).

“Of course, such estimates are not entirely realistic because of differences between species,” Lomax said.

“Nonetheless, simple scaling is commonly used to estimate size, especially when comparative material is scarce.”

In 1850, a large bone was described from the Late Triassic (208 million years old) of Aust Cliff, Gloucestershire, UK.

Four other similarly incomplete bones were also found and described. Two of them are now missing and presumed destroyed.

They have been identified as the limb bones of several dinosaurs (stegosaurs and sauropods), indeterminate dinosaurs and other reptiles.

However, with the discovery of the Lilstock specimen, this new study refutes previous identifications and also the most recent assertion that the Aust bones represent an early experiment of dinosaur-like gigantism in terrestrial reptiles. They are, in fact, jaw fragments of giant, previously unrecognized ichthyosaurs.

“One of the Aust bones might also be an ichthyosaur surangular. If it is, by comparison with the Lilstock specimen, it might represent a much larger animal,” Lomax said.

“To verify these findings, we need a complete giant Triassic ichthyosaur from the UK — a lot easier said than done.”

_____

D.R. Lomax et al. A giant Late Triassic ichthyosaur from the UK and a reinterpretation of the Aust Cliff ‘dinosaurian’ bones. PLoS ONE 13 (4): e0194742; doi: 10.1371/journal.pone.0194742

Source: www.sci-news.com

Anyone Want to Buy a Dinosaur? Two on Sale in Paris

Wednesday, April 11, 2018

A worker assembles the bones of a diplodocus, one of two dinosaur skeletons being sold at auction in Paris on Wednesday

The skeletons of an Allosaurus and a Diplodocus are up for auction in Paris this week, marketed as hip interior design objects—for those with big enough living rooms.

"The fossil market is no longer just for scientists," said Iacopo Briano of Binoche et Giquello, the auction house that is putting the two dinosaurs under the hammer on Wednesday.

"Dinosaurs have become cool, trendy—real objects of decoration, like paintings," the Italian expert told AFP, citing Hollywood actors Leonardo DiCaprio and Nicolas Cage as fans of such outsize prehistoric ornaments.

Cage, however, did hand back the rare skull of a tyrannosaurus bataar, a close cousin of T. rex, that he bought in 2007 after it was found to have been stolen and illegally taken out of Mongolia.

Dinosaur bones are increasingly gracing collectors' cabinets, with another huge skeleton, that of a theropod, expected to fetch up to 1.5 million euros ($1.84 million) when it goes up for auction in June.

Chinese buyers

"For the last two or three years the Chinese have become interested in palaeontology and have been looking for big specimens of dinosaurs found on their soil, for their museums or even for individuals," Briano said.

The new buyers are now bidding against multinational corporations as well as ultra-rich Europeans and Americans, the "traditional" buyers of dinosaur skeletons, Briano added.

In 1997, McDonald's and Walt Disney were among donors stumping up $8.36 million to buy Sue—the most complete and best preserved Tyrannosaurus rex ever found—for the Field Museum of Natural History in Chicago.

"Millions of people come to see it, it's incredible publicity for companies," said Eric Mickeler, a natural history expert for the Aguttes auction house.

Palaeontologists acknowledge that many fossils that go on the block are of limited scientific interest, but important specimens do go up for auction and can, as in Sue's case, be bought through acts of patronage.

Dinosaur skeletons, including the two being auctioned this week, are increasingly being sought as interior design objects, in particular by Chinese buyers

The market remains small and "isn't for everybody", Mickeler said.

Only around five dinosaurs are put up for auction around the world every year.

'People like the teeth'

The allosaurus which goes on sale Wednesday, among 87 lots of natural artefacts, is considered "small" at 3.8 metres (12.5 feet) long.

It is expected to fetch up to 650,000 euros, while the diplodocus—despite being bigger at 12 metres long from nose to tail—has a guide price of 450,000 to 500,000 euros.

Carnivores like the allosaurus often fetch more than herbivores.

"People like the teeth," Mickeler said.

The price also goes up if the skeleton shows traces of a fight or an incurable illness, as well as if it is considered rare, has a high percentage of verified bones, or a particularly impressive skull.

"We recently sold a very beautiful piece to a Venetian family, they have a magnificent big room in which the dinosaur is perfectly at ease," Briano said.

But Ronan Allain, a palaeontologist at the Natural History Museum of Paris, denounced "completely nonsensical" prices.

"It's the luxury world, it's not for people like us," he said.

"We could decide to buy it pre-emptively, but for the theropod, for example, that would mean shelling out more than a million," he said.

Source: https://phys.org

New Study Resolves the Mystery of an Enigmatic Triassic Reptile

Tuesday, April 10, 2018

Scientists from the University of Bristol have re-examined the fossilised remains of a Triassic reptile, currently housed in two separate collections on each side of the Atlantic, and have discovered it is a brand-new kind of beast.

The remains of the reptile, which lived 200 million-years-ago were discovered some decades ago in a South Gloucestershire quarry.

This species, closely related to the living Tuatara from New Zealand, was originally described as Clevosaurus latidens in 1993 by the British paleontologist Nicholas Fraser, referring it to the genus Clevosaurus, already known by many species in the Late Triassic of the south-west of England and South Wales, and elsewhere in the world.

The conundrum was that other species of Clevosaurus were carnivores, whereas the teeth of this beast showed it ate plants.

However, the key fossils are housed in two different collections in the United States and Scotland, and no attempts had been made to re-examine the fossils until now.

The Late Triassic rhynchocephalian Clevosaurus latidens Fraser, 1993 is known from the fissure deposits of Cromhall Quarry, England. Many studies have questioned its referral to the genus Clevosaurus Swinton, 1939 and some phylogenetic analyses suggest a close relationship with herbivorous rhynchocephalians. We re-examine the type specimens and referred material of C. latidens to elucidate its taxonomic identity. Additionally, we provide new phylogenetic analyses of the Rhynchocephalia using both parsimony and Bayesian approaches. Our taxonomic review and both phylogenetic analyses reveal that C. latidens is not referable to Clevosaurus, but represents a new genus. We reassess C. latidens and provide an amended diagnosis for Fraserosphenodon new genus. Both parsimony and Bayesian analyses recover similar topologies and we propose formal names for two higher clades within Rhynchocephalia: Eusphenodontia new infraorder and Neosphenodontia new clade. UUID: http://zoobank.org/65f29bd1-47e3-4a73-af8c-9181c19319e4

Lead author Jorge Herrera-Flores from the University of Bristol's School of Earth Sciences, said: "The restudy of the fossils confirmed our previous suspicions that this species was not related to the carnivorous Clevosaurus.

"It clearly represents a new genus of herbivorous rhynchocephalian, and we are pleased to call it Fraserosphenodon, in honour of Nick Fraser, who first found it, and is now Head of Natural Sciences at the National Museum of Scotland in Edinburgh."

Co-author, Dr. Tom Stubbs, added: "We confirmed the uniqueness of the species by carrying out various numerical analyses of relationships.

"This showed that Fraserosphenodon is a much more advanced rhynchocephalian than Clevosaurus."

Co-author Armin Elsler said: "These Triassic fossils are of huge interest.

"They are close relatives of the living Tuatara, a kind of living fossil, found today only on some islands around New Zealand. We need to understand more about the evolution of this rare and endangered species."

Professor Mike Benton, Jorge's Ph.D. supervisor, added: "I'm delighted we could name this after Nick Fraser, my old classmate at the University of Aberdeen.

"Nick has done great work on Triassic  reptiles, including the rhynchocephalians, from his time in Aberdeen, but also as curator at the Virginia Museum of Natural History, and now in Edinburgh."

More information: Jorge A. Herrera-Flores et al. Taxonomic reassessment of Clevosaurus latidens Fraser, 1993 (Lepidosauria, Rhynchocephalia) and rhynchocephalian phylogeny based on parsimony and Bayesian inference, Journal of Paleontology (2018). DOI: 10.1017/jpa.2017.136

Provided by: University of Bristol

Source: https://phys.org

Newly Found Fossils Go On Show In Dinosaur Museum In Fukui

Monday, April 9, 2018

A complete skeleton of a Tsintaosaurus is displayed on March 17 at a special exhibition at the Fukui Prefectural Dinosaur Museum in Katsuyama, Fukui Prefecture. (Ryo Kageyama)

For dinosaur buffs wanting to see the latest finds, the Fukui Prefectural Dinosaur Museum here is holding a special exhibition showcasing fossils newly discovered in fiscal 2017.

The special exhibition, titled “Excavation 2017,” started March 17. It will run through May 6.

The museum is displaying new fossils found from April 1, 2017, to the end of March 2018 in the series of the fourth excavation between fiscal 2013 and 2018.

Featured fossils include rocks in which the teeth of ankylosauria and the bone fossils of ornithopods have been concentrated.

In the fiscal 2017 excavation, more than 4,000 fragments of vertebrate animals were found. Of these, more than 100 fossils of dinosaurs have been lined up for the special show.

In addition to the authentic fossils, about six complete skeletons related to fossils discovered in Katsuyama are being shown. They include the plant-eating Fukuisaurus, large ornithopod Tsintaosaurus, and a new kind of ankylosauria, “Jinyunpelta,” which was just named in February and will be put on display from the end of March.

On the same day of the start of the exhibition, a 16-meter-tall monument of Rainbow Saurus, the museum’s icon, was unveiled in front of the museum after repair work on it was completed. It was first displayed in 2000.

The fee for the special exhibition is included with regular museum admission of 260 yen ($2.45) for elementary and junior high school students, 410 yen for high school and college students and 720 yen for adults.

Source: www.asahi.com

Radical Plant Hypothesis Blames Dinosaur Extinction on 'Biotic Revenge'

Saturday, April 7, 2018

A small coelurosaur, a feather-tailed dinosaur that lived 99 million years ago, approaching a resin-coated branch on the forest floor.  CHUNG-TAT CHEUNG

The dinosaurs that reigned between 66 and 247 million years ago were massive — some even heavier the space shuttle Endeavour. It seems fitting that they’d meet their end at the hands of a force as powerful as an asteroid and the catastrophic volcanic activity that followed. But a sneakier, more sinister culprit was already wreaking havoc on the dinosaurs long before that asteroid pummeled into the Yucatan Peninsula, evolutionary psychologists argued on Tuesday. In their radical new study, they place the blame on toxic plants.

In the paper, published in the February edition of Ideas in Ecology and Evolution, the University of Albany’s Gordon Gallup, Ph.D. and the University of Baltimore’s Michael Frederick, Ph.D. assert that food poisoning killed the dinosaurs long before the asteroid hit. They call their idea the “biotic revenge” hypothesis.

“Since the spread of toxic plants occurred slowly, that [the hypothesis] is consistent with recent evidence showing that dinosaurs began to disappear millions of years before the asteroid impact and continued to go extinct for millions of years later,” Gallup, a psychology professor at the University at Albany, tells Inverse. “Thus, dinosaurs may have gone extinct because of a simple psychological deficit.”

According to this hypothesis, large, herbivorous dinosaurs ate huge quantities of plant life, including the first toxic angiosperms, which, in turn, gave the dinosaurs great gastrointestinal distress. But because they hadn’t yet figured out taste aversion — that is, learning not to go back to the heinous place last gave you food poisoning — they continued to eat the toxic plants, eventually consuming harmful and lethal doses. This effect of their psychological deficit, they write, “placed additional stress on the species” and “may have done particular damage to dinosaurs” before the asteroid arrived.

The idea of biotic revenge fits in with the increasingly accepted idea that dinosaurs were already in decline millions of years before their semi-final extinction. The fossil record indicates that, before the end of the Cretaceous Period, there already was a slump in dinosaur populations and an increase in the diversity of birds. When Gallup learned that the first toxic plants appeared in the fossil record at about the same time dinosaurs began to go extinct, it dawned on him that this gradual extinction may be linked to the angiosperms.

“The intriguing feature of evolutionary theory,” says Gallup, “is that it enables you to think about things outside the box.”

To back up this claim, Gallup and Frederick examined studies on development of taste aversion among animals that outlived the dinosaurs. Birds, which are thought to have evolved from small meat-eating dinosaurs like velociraptors. Previous studies have shown that present-day birds are capable of learning food aversions, though they do so by sight rather than taste: For example, birds know bright orange monarch butterflies are filled with milkweed toxins, so they’ve learned to avoid them. Gallup and Frederick argue that this psychological ability may have helped birds avoid the fate of other dinosaurs.

They also reevaluated research on crocodilians — which share a common ancestor with dinosaurs and are the closest living relative of birds — that had been conducted by Gallup in 1987, showing that some species didn’t have the capacity for learned taste aversion. By inducing sickness in a group of caimans to see whether they’d associate illness with certain types of foods, they discovered that the caimans were always willing to eat anything, whether it made them sick or not.

This inability to learn taste aversion is a trait that the study authors think could have been shared by dinosaurs, but a lucky quirk of habitat saved them from extinction. The reason that crocodilians didn’t go extinct, they write, is “that being aquatic carnivores, they never had to cope with the problems posed by consuming toxic terrestrial plants.”

Gallup and Frederick are well aware that this unusual hypothesis may make skeptical paleontologists ask: What do a couple of psychologists know about dinosaur extinction? Rather than scoff at their theory, however, they hope paleontologists will help them evaluate the fossil record further in order to test their hypothesis with empirical evidence.

So did early toxic plants enact a biotic revenge? More evidence is necessary to say so definitively. But if dinosaurs really were munching down toxic plants despite extreme belly pain, it’s theoretically possible that their fatal psychological deficit pushed them toward extinction. The asteroid, says Gallup, “certainly played a factor,” but it’s plants that may have “placed severe strain on the species.”

Source: www.inverse.com

Did You Know “Jurassic Park” only Had 6 Minutes of CGI Runtime?

Friday, April 6, 2018

For all its intensity and impressive showing, the film Jurassic Park only had six total minutes of CGI runtime. When you really think about it though six minutes is an eternity in the scope of a film for any scene to play out. In some scenes you become so invested that an entire half hour or more can pass by without you even knowing about it. But in Jurassic Park, despite the impressive nature of the dinosaurs and their rampage throughout the park, the CGI was kept to a minimum since Steven Spielberg didn’t think that it would hold to intense scrutiny quite as well as the animatronic dinos would.

Most of the models within the film are very real, and were used in more than one scene throughout the movie. Some of them were even conceptualized as suits that would be worn by actors. But the CGI is something that people can look at and discern from the real surroundings since in truth it’s not really happening in real time on the set. If you look behind the scenes on any film that uses CGI, and there are a lot of them, you’ll see that the actors are usually being directed to follow a target with their eyes so as to show that they’re watching something pass by, come closer, and so on and so forth. Creating animatronic versions of everything would be an intense and very costly venture for any film set, but Jurassic Park made it work by integrating the story line with the dinosaurs so well that people were waiting with anticipation to see the creatures come bursting out of the foliage and scare the living daylights out of them.

That meant a lot of build up to the movie, which in turn meant that sound and visual effects could be used quite often to denote such a thing as the T. rex clomping its way forward. The impact tremors that you hear in the movie are not realistic since if you study anything concerning the effect of impact tremors and the likelihood of them traveling that far, you might find out that the T. rex was in fact capable of making such tremors. But given that it’s an early warning system and the T. rex is a hunter, it would be foolish of such a creature to do so. That was put in more for effect than anything, and the idea of not moving and having the T. rex lose them played more to the likelihood that the humans would escape without being chomped in half. In reality, the T. rex has been said to have a very keen sense of smell, so every last one of them would have been eaten if reality had been a factor in this movie.

But it’s for entertainment, so the paleontology lesson took a back seat at times to the wonders of Hollywood magic which is pretty normal. Spielberg did manage to listen to those paleontologists that he consulted with and that’s why the movie was as good as it was.

Source: www.tvovermind.com

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