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Paleontologists Find Perfectly Preserved Embryo inside 80-Million-Year-Old Titanosaurian Egg

Tuesday, September 1, 2020

Magnified perspective of the titanosaurian embryonic skull with the preorbital and orbital region in left lateral view. Image credit: Kundrat et al, doi: 10.1016/j.cub.2020.07.091.

Paleontologists recently found well-preserved dinosaur eggs in an enormous nesting ground of titanosaurian sauropod dinosaurs that lived about 80 million years ago (Cretaceous period) in what is now Patagonia, Argentina. In a paper in the journal Current Biology, they now describe an almost intact embryonic skull from one of these eggs, which shows that titanosaurian dinosaurs had stereoscopic vision and an unusual elongated horn on the front of the face which was then lost in adulthood.

“The specimen represents the first 3D preserved embryonic skull of a sauropod sauropodomorph,” said lead author Dr. Martin Kundrat, a researcher at Pavol Jozef Šafárik University.

“The most striking feature is head appearance, which implies that hatchlings of giant dinosaurs may differ in where and how they lived in their earliest stages of life.”

“But because it differs in facial anatomy and size from the sauropod embryos of Auca Mahuevo, Patagonia, we cannot rule out that it may represent a new titanosaurian dinosaur.”

“The preservation of embryonic dinosaurs preserved inside their eggs is extremely rare,” said co-author Dr. John Nudds, a researcher at the University of Manchester.

“Imagine the huge sauropods from Jurassic Park and consider that the tiny skulls of their babies, still inside their eggs, are just a couple of centimeters long.”

Dr. Kundrat, Dr. Nudds and their colleagues used an imaging technology called synchrotron microtomography to study the inner structure of bones, teeth, and soft tissues of the embryonic dinosaur.

The scans allowed the scientists to find hidden details, including tiny teeth preserved deeply in tiny jaw sockets.

They also found partly calcified elements of the embryonic braincase and what appear to be the remains of temporal muscles.

They also reconstructed the most plausible appearance of the skull in titanosaurian sauropods before hatching.

Their findings suggest that the baby sauropods may have hatched out of the egg with the help of a thickened prominence rather than a boney egg-tooth.

Kundrat et al describe an almost intact embryonic skull, which indicates the early development of stereoscopic vision, and an unusual monocerotic face for a sauropod dinosaur. The fossil also reveals a neurovascular sensory system in the premaxilla and a partly calcified braincase, which potentially refines estimates of its prenatal stage. The embryo was found in an egg with thicker eggshell and a partly different geochemical signature than those from the egg-bearing layers described in Auca Mahuevo, Patagonia, Argentina. Image credit: Kundrat et al, doi: 10.1016/j.cub.2020.07.091.

The study authors also uncovered evidence that the embryonic dinosaurs used calcium derived from the eggshell long before they were ready to hatch.

They found that the titanosaurian hatchlings emerged with a temporary moncerotid (single-horned) face, retracted openings on the nose (nares) and early binocular vision.

“We suggest an alternative head appearance for babies of these Patagonian giants,” Dr. Kundrat said.

“We were able to reconstruct the embryonic skull prior to hatching,” Dr. Nudds said.

“The embryos possessed a specialized craniofacial anatomy that precedes the post-natal transformation of the skull in adult sauropods.”

“Part of the skull of these embryonic sauropods was extended into an elongated snout or horn, so that they possessed a peculiarly shaped face.”

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Martin Kundrát et al. Specialized Craniofacial Anatomy of a Titanosaurian Embryo from Argentina. Current Biology, published online August 27, 2020; doi: 10.1016/j.cub.2020.07.091

Source: www.sci-news.com/

How To Weigh A Dinosaur

Tuesday, September 1, 2020

The largest and the smallest: dinosaurs reached an amazing range in size through the Mesozoic Era. Credit: Vitor Silva

How do you weigh a long-extinct dinosaur? There are a couple of ways, as it turns out, neither of which involve actual weighing—but according to a new study, different approaches still yield strikingly similar results.

New research published today in the prestigious journal Biological Reviews involved a review of dinosaur body mass estimation techniques carried out over more than a century.

The findings should lend some confidence that scientists are building an accurate picture of these prehistoric animals, says study leader Dr. Nicolás Campione—particularly the knowledge of the more massive dinosaurs that have no correlates in the modern world.

"Body size, in particular body mass, determines almost at all aspects of an animal's life, including their diet, reproduction, and locomotion," said Dr. Campione, a member of the University of New England's Palaeoscience Research Center.

"If we know that we have a good estimate of a dinosaur's body mass, then we have a firm foundation from which to study and understand their life retrospectively."

Estimating the mass of a dinosaur like the emblematic Tyrannosaurus rex is no small feat—it is a creature that took its last breath some 66 million years ago, and for the most part, only its bones remain today. It is a challenge that has taxed the ingenuity of palaeobiologists for more than a century. Scientific estimates of the mass of the biggest land predator of all time have differed substantially, ranging from about three tons to over 18 tons.

Comparing approaches, dinosaur reconstructions projected onto the limb circumference to body mass scaling relationship of living mammals and reptiles. Credit: Dr Nicolás Campione

The research team led by Dr. Campione compiled and reviewed an extensive database of dinosaur body mass estimates reaching back to 1905, to assess whether different approaches for calculating dinosaur mass were clarifying or complicating the science.

Although a range of methods for estimating body mass have been tried over the years, they all come down to two fundamental approaches. Scientists either measure and scale bones in living animals, such as the circumference of the arm (humerus) and leg (femur) bones, and compared them to dinosaurs; or they calculate the volume of three-dimensional reconstructions that approximate what the animal may have looked like in real life. Debate over which method is better has raged in the literature.

The researchers found that once scaling and reconstruction methods are compared en masse, most estimates agree. Apparent differences are the exception, not the rule.

"In fact, the two approaches are more complementary than antagonistic," Dr. Campione said.

The bone scaling method, which relies on relationships obtained directly from living animals of known body mass, provides a measure of accuracy, but often of low precision, whereas reconstructions that consider the whole skeleton provide precision, but of unknown accuracy. This is because reconstructions depend on our own subjective ideas about what extinct animals looked like, which have changed appreciably over time.

Dr Nicolás Campione standing beside a cast of Tyrannosaurus rex at the Royal Belgian Institute of Natural Sciences in 2009. Credit: David Evans

"There will always be uncertainty around our understanding of long-extinct animals, and their weight is always going to be a source of it," said Dr. David Evans, Temerty Chair of Vertebrate Paleontology at the Royal Ontario Museum in Toronto, senior author on the new paper. "Our new study suggests we are getting better at weighing dinosaurs, and it paves the way for more realistic dinosaur body mass estimation in the future."

The researchers recommend that future work seeking to estimate the sizes of Mesozoic dinosaurs and other extinct animals need to better integrate the scaling and reconstruction approaches to reap their benefits.

Campione and Evans suggest that an adult T. rex would have weighed approximately seven tons—an estimate that is consistent across reconstruction and limb bone scaling approaches alike. But the research emphasizes the inaccuracy of such single values and the importance of incorporating uncertainty in mass estimates, not least because dinosaurs, like humans, did not come in one neat package. Such uncertainties suggest an average minimum weight of five tons and a maximum average weight of 10 tons for the 'king' of dinosaurs.

"It is only through the combined use of these methods and through understanding their limits and uncertainties that we can begin to reveal the lives of these, and other, long-extinct animals," Dr. Campione said.



More information: Campione, N. E. and Evans, D. C. 2020. The accuracy and precision of body mass estimation in non-avian dinosaurs. Biological ReviewsDOI: 10.1111/brv.12638

Journal information: Biological Reviews 

Provided by University of New England 

Source: https://phys.org/

Jurassic World 3 Set Photos Show First Look At Horrifying New Dinosaurs

Thursday, September 3, 2020

Universal/Jurassic_World_Fandom/Twitter

Photographs from the set of Jurassic World: Dominion have given fans a look at what appears to be a horrifying new species of dinosaur.

Shared by the Jurassic World news Twitter account Jurassic_World_Fandom, the photograph shows a maquette rather than an animatronic, and it’s thought the design could change before we see these guys wreaking havoc on the big screen.

The pictures in question appear to have been taken on set in Malta, where shooting has previously been impacted by the ongoing coronavirus pandemic.

Interestingly, Jurassic_World_Fandom noted that we could well be looking at the small but ferocious Pyroraptor, which it reported on a few months back.

According to Jurassic Wiki, you can create a Pyroraptor in Jurassic World: The Game; however, these fearsome beasts have yet to make their cinematic debut:

Unlike most dromaeosaurids in the Jurassic Park Franchise, this depiction of Pyroraptor has fur like feathers all over its body and even wings, making it one of the few fully feathered dromaeosaurids in the franchise, along with Utahraptor.

Unlike some of the man-made monstrosities introduced in the first Jurassic World movie – such as the humungous yet purely fictional Indominus rex – this nightmarish dinosaur did indeed once walk the planet.

The Pyroraptor – which means ‘fire thief’ – lived an approximate 70.6 million years ago, and was a small, bird-like predator with enlarged curved claws. It’s believed they were covered in feathers, which for some reasons feels even more unsettling than scales.

However, nothing is definite, and Jurassic_World_Fandom has added that we could also be looking another sort of dinosaur, suggesting ‘Herrerasaurus, Deinonychus, or some other genus of Raptor’ as other potential candidates.

Jeff Goldblum himself, who will of course be reprising the role of Dr. Ian Malcolm for the upcoming movie, has recently hinted at some ‘surprising’ new prehistoric creatures during an interview with Insider, revealing:

The first thing that we shot … it was a scene with me, and Laura Dern and Sam Neill and we were – I can’t tell you much – but we were all day in a very tight, enclosed space.

You’ll see – it’s a mystery you’ll solve when you see [the movie.] The three of us were in a tiny little space and we were being menaced by – I can’t even tell you – a surprising faction of prehistoric creatures that you’ve never seen before.

We saw some amazing things. We were acting in a life and death situation. We think it might be the last moments of our lives and we’re all bonding with each other in an emotional and somewhat hilarious way.

There is still a fair bit of time to wait until the park’s famous doors reopen once again, but these new pics have admittedly already made me feel a little bit excited for our return.

Jurassic World 3 will stomp into UK cinemas from June 21, 2021.

Source: www.unilad.co.uk/

Jurassic World 3 Filming Through The End Of October

Monday, August 31, 2020

Jeff Goldblum, one of the returning stars for Jurassic World 3, says the latest installment in the franchise is filming through the end of October.

Jurassic World: Dominion will be filming through the end of October, according to one of the returning stars of the film. Jurassic World: Dominion is the third part of the new Jurassic World trilogy, and it will follow on from 2018’s Fallen Kingdom ending, which saw the dinosaurs finally entering the world outside the island. However, the latest installment will also look to tie the entire franchise together by bringing back Jurassic Park originals Sam Neill, Jeff Goldblum, and Laura Dern for major roles. Also, there have already been teases to tie-ins with The Lost World and Jurassic Park 3 by hinting at a return to Isla Sorna (Site B).

Dominion has faced some setbacks due to the coronavirus, as the filming was halted by the pandemic back in March, which director Colin Trevorrow said actually helped them sort through some of the visual effects sequences they already filmed. Dominion was, however, one of the first productions to restart, as filming recommenced at the beginning of July in the UK with the aid of health and safety procedures worth up to $5 million to combat the coronavirus. Universal also had to deny the production shut down again due to an outbreak, but an outbreak did affect their plans to shoot in Malta. Now, one of the film’s stars has provided an update on Jurassic World 3’s shooting schedule.

In an interview with Awards Circuit, Jeff Goldblum offered an update about his current quarantining location in England for Dominion’s filming and also went on to explain how long he expects to be there for. “We’re quarantining right now in England because we’re shooting this Jurassic World: Dominion. We’ve been here about a month and I’ll be here till the end of October, shooting this with Lauren Dern and Sam Neill, and Chris Pratt and Bryce Dallas Howard.”  Goldblum would also praise their director Trevorrow saying, “Colin Trevorrow is the great writer/director of this.”

Goldblum seems to have given a timeline on when people can expect the production of Dominion to wrap. The end of October not only fits in with Neill’s timeline of the actors being together for “three or four months,” but considering Goldblum reportedly has a major role in the film, it’s quite possible he’ll be a part of the filming until the end. If shooting does conclude at the end of October, or not long after, it also means the team will have a good amount of time to put the film together and tweak visual effects to ensure it is ready for the scheduled June 11, 2021 release.

Jurassic World: Dominion looks to be an action-packed finale for the franchise thus far, as not only will it feature former stars, but the film looks set to explore the dinosaurs in a a brand new, arctic setting as well. Stars like Bryce Dallas Howard and Neill have already praised the film, with Neill calling it the “best yet.” Expectations are certainly high, and fans of the franchise will be excited to hear filming is going well, and a possible end date for the Jurassic World 3 filming is in sight.

Source: Awards Circuit / https://screenrant.com/

Why Jurassic Park Cut Hammond's Death (& Ruined The Ending)

Tuesday, September 1, 2020

Why Steven Spielberg's Jurassic Park cut John Hammond's death and why it ruined part of the blockbuster dinosaur movie's ending.

John Hammond should have died at the end of Jurassic Park and Steven Spielberg's decision not to kill him ruined the message of the film's ending. Played by Richard Attenborough with the sort of misty-eyed enthusiasm his natural historian brother David would be proud of, Hammond is, of course, the driving force behind Jurassic Park. The entire endeavor is based on his vision and his dream to give everyone something truly wonderful.

In Michael Crichton's original novel, John Hammond is a significantly less likable character, blinded completely by his ambition (and his greed) and fatally ignorant of the disaster that his park becomes around him. The book version of the character doesn't survive the story, dying at the tiny claws of a flock of Procompsognathus (Compies) as he contemplates his plan for opening a new park only a short time after the death of Mr. Arnold. His movie counterpart is softer at the edges, but he remains just as driven and there is a significant spark of his blind ambition in him.

Steven Spielberg's adaptation of Jurassic Park lets John Hammond off all too easily, allowing him the opportunity to turn his back on his park by the end and humorously pulling his endorsement of Jurassic Park as the survivors flee. But Jurassic Park should have followed through on killing Hammond because his death was still deserved, and the ending was poorer for changing his fate.

John Hammond Should Be The Second Villain Of Jurassic Park

John Hammond is not as much of a villain as Jurassic World's Vic Hoskins (Vincent D'Onofrio), but he shares the same thing that gets Hoskins killed: an insatiable ambition that fundamentally disrespects nature. Both wish to exploit the dinosaurs, albeit in different ways and both would probably follow through on incredibly dangerous aspirations were it not for dramatic impediments. Hoskins dies for his sins, but Hammond is allowed to live because he's played by Richard Attenborough and because Steven Spielberg wanted to leave the door open to him returning in the sequel. Which he did for a very slight cameo, revealing his redemption as a naturalist who believed his dinosaurs should be left to live freely on Isla Sorna but that wasn't enough.

Early storyboards for Jurassic Park actually revealed initial plans to have Hammond killed in a velociraptor attack, but the sequence didn't make it to the final film. That reprieve meant Hammond is never brought to justice for his negative influence on Dennis Nedry, who turns to the desperate measures of stealing embryos because of financial worries that Hammond willfully ignores. Even when Hammond has his supposed redemption moment when eating ice cream with Ellie Satler in the Visitor Center, Hammond holds onto the idea of launching a new park with "more control" up to the very last moment. It's only when he's scolded by Satler that he seems to change track, but having him change his heart after holding onto a dream since he was a child doesn't ring true.

Why John Hammond Should Have Died In Jurassic Park

Jurassic Park is a morality tale about anxiety over humanity's over-reaching fascination with science. It is a modern Frankenstein story and in such stories, those who "play God" and do not respect the natural order - who "destroy God" in the words of Jeff Goldblum's Dr. Ian Malcolm should be killed for their defiance. That they have grandchildren they don't want to be eaten by dinosaurs shouldn't come into it.

In not killing him, Spielberg gives Hammond what amounts to a slap on the wrist for his defiance of the natural order and his unwillingness to learn his lessons. The original Jurassic Park ending, as written by Michael Crichton, would have offered a far more satisfying conclusion to Hammond's obsession with his magical flea circus that had cost so many lives. And that's not to mention the irony that a man so obsessed with the idea of control (even after his supposed "redemption moment" over ice cream) would be killed by the smallest of his dinosaurs.

In the end, we do get to see John Hammond's book death, in a way, because the scene was rescued from the cutting room floor and re-worked for the death of Dieter Stark (Peter Stormare) in The Lost World: Jurassic Park. Sadly, because Stormare's character is little more than a grunt - whose death comes as he's relieving himself in the forest - it has little impact other than in comic terms and the sequel barely gives him a second thought. It should have been Hammond and it should have come as part of the ending of Jurassic Park.

Source: https://screenrant.com/

Sounds Like Jeff Goldblum Has a Lot More Than Just a Cameo in Jurassic World 3

Saturday, August 29, 2020

Returning star Jeff Goldblum has offered some promising insight into the filming of Jurassic World: Dominion.

Jurassic World 3 finally returned to filming recently after a forced hiatus, and star Jeff Goldblum has provided a few insights into how long he will be involved, as well as who else we can expect to see when the movie is released onto the big screen. The movie is set to feature the triumphant return of not only Goldblum, but also previous heroes Sam Neill and Laura Dern, with the actor confirming that the three of them will be filming for a little while longer yet.

"We're quarantining right now in England because we're shooting this Jurassic World: Dominion. We've been here about a month and I'll be here till the end of October, shooting this with Lauren Dern and Sam Neill, and Chris Pratt and Bryce Dallas Howard. Colin Trevorrow is the great writer/director of this. It's got a lot of people. I bet you know some of these other people. Mamoudou Athie and DeWanda Wise, BD Wong, Dichen Lachman, Justice Smith, Daniella Pineda. It's gonna be good."

It should please Jurassic Park fans to know that, with that amount of time spent in front of the camera, Jeff Goldblum's role in the movie is sure to be a lot more than the cameo that most had first feared.

Goldblum has previously regaled us with the details regarding the extensive health and safety procedures that have now had to be put in place due to the ongoing global situation. "They gave us 109 pages," the actor said of the rules and regulations document that went to every member of the cast and crew. "They invested all their heart and soul, and a lot of money, into making sure that we're safe. I won't bore you with the details, but we're all going to be quarantined in a kind of a bubble, all the crew and all the cast. And testing and everything."

"We know it's a risky time, but we feel it's good," he added. "Sam Neill's there and Laura Dern and Chris Pratt and Bryce Dallas Howard; Colin Trevorrow's directing, and there are gonna be some dinosaurs."

Much like Avengers: Endgame before it, the upcoming Jurassic World: Dominion is bringing back everybody from the previous movies. Everybody that's still alive, at least. From Chris Pratt's Owen Grady to Sam Neill's Alan Grant, the sequel will see characters from across the franchise come together to take on the dinosaur threat.

The last movie in the ongoing franchise, Jurassic World: Fallen Kingdom, ended with several of the creatures being smuggled off the island for a black-market auction which, of course, ends terribly. With the dinosaurs now let loose upon the world, Jurassic World: Dominion will see the likes of Jeff Goldblum's Dr. Ian Malcolm, along with Sam Neill's Dr. Alan Grant and Laura Dern's Dr. Ellie Sattler, brought back into the fray to help stop the prehistoric beasts.

While it was long-rumored that the third Jurassic World movie would be the last entry in the series, this was cleared up by producer Frank Marshall who recently stated that "It's the start of a new era... The dinosaurs are now on the mainland amongst us, and they will be for quite some time, I hope."

Jurassic World: Dominion has not had to adjust release, and so is still set to stomp into theaters on June 11, 2021. This comes to us from Awards Circuit.

Source: https://movieweb.com/

Jurassic World 3: Why Dominion Has So Many Legacy Characters

Tuesday, September 1, 2020

Jurassic World: Dominion is bringing back Sam Neill, Laura Dern, and Jeff Goldblum and here's why Jurassic Park's legacy characters are in the film.

Jurassic World: Dominion brings back lots of the beloved legacy characters from Steven Spielberg's 1993 blockbuster, Jurassic Park, and this is to bring the saga full-circle to complete the link between the Jurassic World trilogy and the Jurassic Park films. Directed by Colin Trevorrow, who helmed 2015's Jurassic World, and scheduled for release in 2021, Jurassic World: Dominion stars Chris Pratt as Owen Grady and Bryce Dallas Howard as Claire Dearing but it also brings back Sam Neill as Dr. Alan Grant, Laura Dern as Dr. Ellie Sattler, and Jeff Goldblum as Dr. Ian Malcolm.

Following the events of 2018's Jurassic World: Fallen Kingdom, the dinosaurs of Isla Nublar are now loose upon the world after dozens were rescued when the island was destroyed by a volcanic eruption. The dinosaurs were brought to Lockwood Manor in Northern California to be sold in an illegal dinosaur auction. However, the cloned beasts were released from captivity by Maisie Lockwood (Isabella Sermon), who is, herself, a perfect human clone. Despite Ian Malcolm's warnings, by the end of the second film directed by J.A. Bayona, the Earth has indeed become a Jurassic World as the dinosaurs have spread out across the planet. Further, because the dinos are loose, the cloning tech that created them can now be copied and is no longer proprietary to InGen, the corporation founded by the late John Hammond (Richard Attenborough).

The Jurassic World films have leaned on nostalgia and evoked story beats and imagery from the Jurassic Park movies but the first two Jurassic Worlds were actually careful not to utilize the legacy characters from the original trilogy; even Jeff Goldblum's much-hyped return as Ian Malcolm in Fallen Kingdom only amounted to a few minutes of screen time. However, Jurassic World: Dominion promises that Alan Grant, Ellie Sattler, and Ian Malcolm will appear "all throughout the film" and will factor in significantly in the dino action, alongside Owen Grady, Claire Dearing, and the newer Jurassic World characters. Plus, along with Jurassic Park's "Big Three", Jurassic World: Dominion will also see the return of Dr. Henry Wu (B.D. Wong), who became a villain in the new trilogy, and Lewis Dodgson (Campbell Scott), the villain from Jurassic Park who once bribed Dennis Nedry (Wayne Knight) to steal InGen's dinosaur embryos in a shaving cream can.

Trevorrow told Empire that part of the fun of bringing back the original Jurassic Park trio is that it asks the big questions audiences want to know: "Who are these people now? What do they make of the new world they’re living in, and how do they feel about being part of its history?" After all, Grant and Sattler last appeared together in 2001's Jurassic World III where Alan was tricked into traveling to the dinosaur-infested Isla Sorna, AKA Site B. Malcolm also previously survived his own trip to Site B in 1997's The Lost World: Jurassic Park. But in Jurassic World: Dominion, with dinosaurs no longer confined to an island and loose upon the planet, it makes perfect sense that the world's foremost experts in facing InGen's cloned dinos are thrust back into action.

Not only are fans excited to see Grant, Sattler, and Malcolm back in action but the actors also wanted to be part of the final film in the Jurassic World trilogy. In 2017, Laura Dern told MovieWeb, "I said to the people who are making the new series, 'If you guys make a last one, you gotta let Ellie Sattler come back'." The new cast of Jurassic World is also thrilled to work alongside the original Jurassic heroes. Chris Pratt said to Yahoo! that Jurassic World: Dominion would be like "the Avengers: Endgame of Jurassic movies... It's got pretty much everybody in it... It's going to feel very much like how Endgame brought everything together for Marvel." Hopefully, Jurassic World: Dominion delivers the grand finale that satisfyingly concludes the six-film Jurassic saga and gives the legacy Jurassic Park characters the fitting sendoff they, and the fans, deserve.

Source: https://screenrant.com/

Paleontologists Find Evidence of Hibernation-Like State in Tusks of Triassic Mammal Relative

Saturday, August 29, 2020

An artist’s impression of Lystrosaurus. Image credit: Victor O. Leshyk, www.victorleshyk.com / University of Birmingham.

In a paper published in the journal Communications Biology, a team of U.S. paleontologists reports evidence of a hibernation-like condition in Lystrosaurus, an early relative of mammals that lived between 253 and 248 million years ago (Early Triassic period). The discovery was enabled by high-resolution of incremental growth marks preserved in the fossilized tusks of Lystrosaurus from Antarctica.

Lystrosaurus is a type of dicynodont, a major group of primarily herbivorous vertebrates that were common during the Permian and Triassic periods.

The ancient creature was between 1.8 and 2.4 meter (6-8 feet) in length, had no teeth, but bore a pair of tusks in the upper jaw.

The fossilized remains of Lystrosaurus are known from China, Europe, India, South Africa and Antarctica and this geographic distribution was one of the early pieces of evidence used in support of the large supercontinent Pangea.

The animal’s fossils have been found in burrow structures in South Africa and similar burrow trace fossils have been recovered from Antarctica, but not with Lystrosaurus inside them.

Lystrosaurus arose before Earth’s largest mass extinction at the end of the Permian period — which wiped out 70% of vertebrate species on land — and somehow survived.

“The fact that Lystrosaurus survived the end-Permian mass extinction and had such a wide range in the early Triassic has made them a very well-studied group of animals for understanding survival and adaptation,” said Burke Museum’s Professor Christian Sidor, co-author of the study.

Measurements for stress and regular growth were recorded from the tusks of Lystrosaurus: (a) a cross-section of the Antarctic specimen with a ‘hibernation zone’ highlighted at a higher magnification. Scale bars – 1,000 μm; (b) well-preserved regular incremental growth marks from the South African specimen, lacking ‘hibernation zones.’ Arrows denote individual lines with an average spacing of 16-20 μm. Scale bar – 100 μm. Image credit: Whitney & Sidor, doi: 10.1038/s42003-020-01207-6.

The Lystrosaurus fossils from the Fremouw Formation of Antarctica are the oldest evidence of a hibernation-like state in a vertebrate animal and indicate that torpor — a general term for hibernation and similar states in which animals temporarily lower their metabolic rate to get through a tough season — arose in vertebrates even before mammals and dinosaurs evolved.

“Animals that live at or near the poles have always had to cope with the more extreme environments present there,” said lead author Dr. Megan Whitney, a postdoctoral researcher at Harvard University.

“These preliminary findings indicate that entering into a hibernation-like state is not a relatively new type of adaptation. It is an ancient one.”

The Lystrosaurus tusks made the study possible because, like elephants, their tusks grew continuously throughout their lives.

Taking cross-sections of the fossilized tusks revealed information about the animal’s metabolism, growth and stress or strain.

The paleontologists compared cross-sections of tusks from six Antarctic Lystrosaurus to cross-sections of four Lystrosaurus from South Africa.

The tusks from the two regions showed similar growth patterns, with layers of dentine deposited in concentric circles like tree rings.

The Antarctic fossils, however, held an additional feature that was rare or absent in tusks farther north: closely-spaced, thick rings, which likely indicate periods of less deposition due to prolonged stress.

“The closest analog we can find to the stress marks that we observed in Antarctic Lystrosaurus tusks are stress marks in teeth associated with hibernation in certain modern animals,” Dr. Whitney said.

The researchers cannot definitively conclude that Lystrosaurus underwent true hibernation.

The stress could have been caused by another hibernation-like form of torpor, such as a more short-term reduction in metabolism.

Lystrosaurus in Antarctica likely needed some form of hibernation-like adaptation to cope with life near the South Pole,” Dr. Whitney said.

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M.R. Whitney & C.A. Sidor. 2020. Evidence of torpor in the tusks of Lystrosaurus from the Early Triassic of Antarctica. Commun Biol 3, 471; doi: 10.1038/s42003-020-01207-6

Source: www.sci-news.com/

Giant Miocene Caiman Preyed on Ground Sloths

Friday, August 28, 2020

Life reconstruction of the putative attack of a young to sub-adult Purussaurus on the ground sloth Pseudoprepotherium in a swamp of proto-Amazonia. Image credit: Jorge A. González.

Purussaurus, a top predator that lived in the wetlands of proto-Amazonia between 6 and 13 million years ago (Miocene epoch), hunted not only aquatic animals but also land-dwelling creatures like ground sloths, according to a paper published in the journal Biology Letters.

Following the extinction of non-avian dinosaurs, the largest continental predator was neither a mammal nor a bird, but the giant caiman Purussaurus.

This carnivorous animal inhabited South America during the middle and late Miocene, when a system of wetlands flourished in northwestern Amazonia.

Purussaurus exceeded 10 m (33 feet) long and had a broad, massive skull and robust jaws with conical and blunt teeth.

In October 2004, Dr. François Pujos of the Instituto Argentino de Nivología and colleagues discovered Miocene-epoch bonebeds near Iquitos City in Peru.

One bonebed preserved swamp deposits bearing diverse aquatic and land-dwelling vertebrate assemblages, particularly rich in fish, turtle, reptile and mammal remains.

Among the fossils, the paleontologists found a 13-million-years-old severely damaged long bone of a massive mammal.

The team’s preliminary examination of the specimen revealed 46 tooth marks that were inflicted prior to fossilization.

Left tibia of Pseudoprepotherium and mapping of the bite marks: photograph and schematic drawing in anterior (i and ii) and posterior (iii and iv) views. Image credit: François Pujos & Rodolfo Salas-Gismondi, doi: 10.1098/rsbl.2020.0239.

In a new study, Dr. Pujos and his colleague, Dr. Rodolfo Salas-Gismondi from the Universidad Peruana Cayetano Heredia, aimed to identify the putative perpetrator of the attack and its victim.

They found that the bone belonged to Pseudoprepotherium, a middle-sized ground sloth (body weight – 78.5 kg, equivalent to a large capybara) that lived in Colombia, Brazil and Venezuela during the Miocene.

“The combination of round and bisected, shallow pits and large punctures that collapsed extensive portions of cortical bone points to a young or sub-adult Purussaurus neivensis (approximately 4 m, or 13.1 feet, in total length) as the perpetrator,” the researchers said.

“The pattern of tooth marks suggests that the perpetrator attacked and captured the ground sloth from the lower hind limb, yet an attempt of dismembering cannot be ruled out.”

“This discovery from the Peruvian Amazonia provides an unusual snapshot of the dietary preferences of Purussaurus,” they added.

“It also reveals that prior to reaching its giant size, young individuals might have fed upon terrestrial mammals of about the size of a capybara.”

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François Pujos & Rodolfo Salas-Gismondi. 2020. Predation of the giant Miocene caiman Purussaurus on a mylodontid ground sloth in the wetlands of proto-Amazonia. Biol. Lett 16 (8): 20200239; doi: 10.1098/rsbl.2020.0239

Source: www.sci-news.com/

Scelidosaurus harrisonii: Paleontologist Redescribes Enigmatic Armored Dinosaur from Jurassic Period

Saturday, August 29, 2020

Scelidosaurus harrisonii. Image credit: John Sibbick.

Scelidosaurus harrisonii, an armored dinosaur that lived around 193 million years ago (Early Jurassic period), has been redescribed from a near-complete skeleton discovered over 160 years ago in England.

Scelidosaurus harrisonii is an early armored ornithischian dinosaur whose remains have, to date, only been recovered from a paleontological site on the south coast of Dorset, England.

This dinosaur has been known since 1859, but only on the basis of a partial description found in two short articles published in the early 1860s by Richard Owen from the British Museum in London.

The original material, discovered in 1858, comprised the majority of the skull and its associated postcranial skeleton, and represents the first ever, more or less complete dinosaur discovered.

Over the past three years, University of Cambridge paleontologist David Norman has devoted much of his time to preparing a detailed description and biological analysis of Scelidosaurus harrisonii, completing a project more than 150 years in the making.

Scelidosaurus harrisonii represents a species that appeared at, or close to, the evolutionary ‘birth’ of the Ornithischia,” Dr. Norman said.

“Given that context, what was actually known of Scelidosaurus harrisonii? The answer: remarkably little!”

“Nobody knew that the skull had horns on its back edge. It also had several bones that have never before been recognized in any other dinosaur,” he added.

“It is also clear from the rough texturing of the skull bones that it was, in life, covered by hardened horny scutes — a little bit like the scutes plastered over the surface of the skulls of living turtles.”

“Its entire body was protected by skin that anchored an array of stud-like bony spikes and plates.”

Scelidosaurus harrisonii had been seen for many decades as an early member of the group that included the stegosaurs and ankylosaurs, but that was based on a poor understanding of its anatomy.

Now it seems that Scelidosaurus harrisonii is an ancestor of the ankylosaurs alone.

“It is unfortunate that such an important dinosaur, discovered at such a critical time in the early study of dinosaurs, was never properly described,” Dr. Norman said.

“It has now been described in detail and provides many new and unexpected insights concerning the biology of early dinosaurs and their underlying relationships.”

The results were published in a series of four papers in the Zoological Journal of the Linnean Society of London.

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David B. Norman. 2020. Scelidosaurus harrisonii from the Early Jurassic of Dorset, England: cranial anatomy. Zoological Journal of the Linnean Society 188 (1): 1-81; doi: 10.1093/zoolinnean/zlz074

David B. Norman. 2020. Scelidosaurus harrisonii from the Early Jurassic of Dorset, England: postcranial skeleton. Zoological Journal of the Linnean Society 189 (1): 47-157; doi: 10.1093/zoolinnean/zlz078

David B. Norman. 2020. Scelidosaurus harrisonii from the Early Jurassic of Dorset, England: the dermal skeleton. Zoological Journal of the Linnean Society 190 (1): 1-53; doi: 10.1093/zoolinnean/zlz085

David B. Norman. Scelidosaurus harrisonii (Dinosauria: Ornithischia) from the Early Jurassic of Dorset, England: biology and phylogenetic relationships. Zoological Journal of the Linnean Society, publihsed online August 18, 2020; doi: 10.1093/zoolinnean/zlaa061

Source: www.sci-news.com/

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