nandi's blog

2-Million-Year-Old Skull of Paranthropus robustus Suggests Climate Change Drove Rapid Changes

Wednesday, November 11, 2020

The DNH 155 cranium of Paranthropus robustus photographed in frontal (a), left lateral (b), superior (c) and oblique (d) views. Scale bar – 10 mm. Image credit: Martin et al., doi: 10.1038/s41559-020-01319-6.

Paranthropus robustus is a small-brained extinct hominin that lived between 2 million and 1.2 million years ago in what is now South Africa. Discovered in 1938, it was among the first early hominins described and the first discovered robust australopithecine. Paranthropus robustus males were thought to be substantially larger than females — much like the size differences seen in modern-day primates. But the well-preserved adult male skull of Paranthropus robustus from the Drimolen cave system northwest of Johannesburg in South Africa, dated from approximately 2.04-1.95 million years ago, instead suggests that this hominin evolved rapidly during a period of local climate change about 2 million years ago, resulting in anatomical changes that previously were attributed to sex.

Paleoanthropologists already knew that the appearance of Paranthropus robustus in South Africa roughly coincided with the disappearance of Australopithecus and the emergence in the region of early Homo.

This transition took place very rapidly, perhaps within only a few tens of thousands of years.

“The working hypothesis has been that climate change created stress in populations of Australopithecus leading eventually to their demise, but that environmental conditions were more favorable for Homo and Paranthropus, who may have dispersed into the region from elsewhere,” said Professor David Strait a researcher at Washington University in St. Louis.

“We now see that environmental conditions were probably stressful for Paranthropus as well, and that they needed to adapt to survive.”

The newly-discovered specimen from the Drimolen site, designated DNH 155, is clearly a Paranthropus robustus male.

It is larger than a well-studied member of the species previously discovered at the site — an individual known as DNH 7, and presumed to be female — but is measurably smaller than presumed males from the nearby site of Swartkrans.

“It now looks as if the difference between the two sites cannot simply be explained as differences between males and females, but rather as population-level differences between the sites,” said first author Jesse Martin, a doctoral student at La Trobe University.

“Our recent work has shown that Drimolen predates Swartkrans by about 200,000 years, so we believe that Paranthropus robustus evolved over time, with Drimolen representing an early population and Swartkrans representing a later, more anatomically derived population.”

“It’s very important to be able to document evolutionary change within a lineage. It allows us to ask very focused questions about evolutionary processes,” added co-author Dr. Angeline Leece, also from La Trobe University.

Paranthropus boisei. Image credit: © Roman Yevseyev.

The evidence of rapid but significant climate change during this period in South Africa comes from a variety of sources.

Critically, fossils indicate that certain mammals associated with woodland or bushland environments went extinct or became less prevalent — while other species associated with drier, more open environments appeared locally for the first time.

“As is the case today, shifting climates alter local environments, and the rapid appearance of a more open, arid and cooler environment in South Africa at this time resulted in a change to the local ecology and thus, to the foods available on the landscape,” said co-author Dr. Gary Schwartz, a researcher at Arizona State University.

“We already knew that Paranthropus robustus had evolved a host of anatomical specializations of the skull that allowed it to consume and survive on the sorts of hard, tough, difficult-to-process foods.”

“But when compared to geologically younger specimens from the nearby site of Swartkrans, the Drimolen cranium very clearly shows that it was less well adapted to eating these challenging menu items.”

“What we have is a remarkable snapshot of how a dry climate led to natural selection altering the anatomy of this one species over only 200,000 years from the less-efficient form at Drimolen to the evolution of a more powerful feeding apparatus present in Swartkrans Paranthropus robustus.”

“It was notable that Paranthropus robustus appeared at roughly the same time as our direct ancestor Homo erectus, as documented by an infant Homo erectus cranium that the team discovered at the same Drimolen site in 2015,” Dr. Leece said.

“These two vastly different species, Homo erectus with their relatively large brains and small teeth, and Paranthropus robustus with their relatively large teeth and small brains, represent divergent evolutionary experiments.”

“While we were the lineage that won out in the end, the fossil record suggests that Paranthropus robustus was much more common than Homo erectus on the landscape two million years ago.”

“These two genera lived alongside a third genus of early human ancestor, Australopithecus, also present from sites within the same small valley,” Dr. Schwartz said.

“How these hominins divided up the landscape, especially during this period of radically shifting environments, is not yet clear and that is a major focus of our future research.”

“Drimolen is fast becoming a hotspot for early hominin discoveries, which is a testament to the current team’s dedication to holistic excavation and post-field analysis,” said co-author Dr. Stephanie Baker, a researcher at the University of Johannesburg.

“The DNH 155 cranium is one of the best-preserved Paranthropus robustus specimens known to science.”

“This is an example of what careful, fine-scale research can tell us about our distant ancestors.”

The research is described in a paper published online in the journal Nature Ecology & Evolution.

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J.M. Martin et al. Drimolen cranium DNH 155 documents microevolution in an early hominin species. Nat Ecol Evol, published online November 9, 2020; doi: 10.1038/s41559-020-01319-6

Source: www.sci-news.com

Kylinxia zhangi: Cambrian Shrimp-Like Arthropod Had Five Eyes

Saturday, November 7, 2020

Life reconstruction of Kylinxia zhangi. Image credit: Diying Huang.

Paleontologists in China have uncovered exceptionally preserved fossils of a previously unknown genus and species of extinct arthropod, Kylinxia zhangi, that provides important insights into the phylogenetic relationships among early arthropods, the evolutionary transformations and disparity of their frontal appendages, and the origin of crucial evolutionary innovations in the phylum Euarthropoda.

Kylinxia zhangi swam in the Early Cambrian seas, approximately 518 million years ago.

The six specimens with well-preserved soft parts of this ancient creature were found in the Yu’anshan Formation in Yunnan province, southern China.

They show an unexpected mix of distinctive features of true arthropods as well as more ancient features.

Kylinxia zhangi had a fused head shield, a segmented trunk, and jointed legs.

But it also had raptorial frontalmost appendages and five stalked compound eyes, of which the anterior (forward-facing) two are at least twice as large as the posterior three.

“This configuration of eyes is reminiscent of the peculiar five eyes in Opabinia regalis,” the paleontologists said.

The holotype of Kylinxia zhangi. Image credit: Han Zeng.

Kylinxia zhangi was a member of the Chengjiang biota, the most diverse assemblage of Early Cambrian marine fossils known.

“Among the Chengjiang fauna, the giant top predator Anomalocaris is considered the ancestral form of arthropod,” the researchers said.

“But huge morphological differences exist between Anomalocaris and true arthropods. There is a great evolutionary gap between the two that can hardly be bridged.”

“Our results indicate that the evolutionary placement of Kylinxia zhangi is right between Anomalocaris and the true arthropods,” said co-author Professor Maoyan Zhu, a paleontologist at the Nanjing Institute of Geology and Palaeontology.

“Therefore, our finding reached the evolutionary root of the true arthropods.”

Kylinxia zhangi represents a crucial transitional fossil predicted by Darwin’s evolutionary theory,” added lead author Dr. Han Zeng, also from the Nanjing Institute of Geology and Palaeontology.

“It bridges the evolutionary gap from Anomalocaris to true arthropods and forms a key ‘missing link’ in the origin of arthropods, contributing strong fossil evidence for the evolutionary theory of life.”

The team’s paper was published in the journal Nature.

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H. Zeng et al. An early Cambrian euarthropod with radiodont-like raptorial appendages. Nature, published online November 4, 2020; doi: 10.1038/s41586-020-2883-7

Source: www.sci-news.com

Meet Ajnabia odysseus, First Duck-Billed Dinosaur from Africa

Friday, November 6, 2020

An artist’s impression of a group of hadrosaurs. Image credit: Raul Martin.

An international team of paleontologists has identified a new genus and species of lambeosaurine hadrosaur from fossils dug up in Morocco, North Africa.

The newly-discovered dinosaur, dubbed Ajnabia odysseus, roamed our planet some 66 million years ago during the Maastrichtian age of the Late Cretaceous period.

The ancient creature was a member of Hadrosauridae, a large family of plant-eating dinosaurs that grew up to 15 m (50 feet) long.

But Ajnabia odysseus was just 3 m (10 feet) long — very small compared to its kin.

“The discovery of the new fossil in a mine a few hours from Casablanca was about the last thing in the world you would expect,” said lead author Dr. Nicholas Longrich, a paleontologist in the Milner Centre for Evolution at the University of Bath.

“It was completely out of place, like finding a kangaroo in Scotland. Africa was completely isolated by water — so how did they get there?”

The fossilized jawbones and teeth of Ajnabia odysseus were found in the Office Chérifien des Phosphates mines at Sidi Chennane in Morocco’s Khouribga province.

The fossils show it belonged to Lambeosaurinae, a subfamily of hadrosaurs with elaborate bony head crests.

These dinosaurs evolved in North America before spreading to Asia and Europe, but have never been found in Africa before.

Because Africa was an island continent in the Late Cretaceous, isolated by deep seaways, they must have crossed hundreds of kilometers of open water — rafting on debris, floating, or swimming — to colonize the continent.

Hadrosaurs were probably powerful swimmers — they had large tails and powerful legs, and are often found in river deposits and marine rocks, so they may have simply swum the distance.

“It was impossible to walk to Africa,” Dr. Longrich said.

“These dinosaurs evolved long after continental drift split the continents, and we have no evidence of land bridges.”

“The geology tells us Africa was isolated by oceans. If so, the only way to get there is by water.”

“As far as I know, we’re the first to suggest ocean crossings for dinosaurs.”

The findings were published in the journal Cretaceous Research.

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Nicholas R. Longrich et al. The first duckbill dinosaur (Hadrosauridae: Lambeosaurinae) from Africa and the role of oceanic dispersal in dinosaur biogeography. Cretaceous Research, published online November 2, 2020; doi: 10.1016/j.cretres.2020.104678

Source: www.sci-news.com/

Kataigidodon venetus: New Cynodont Species Unearthed in Arizona

Friday, November 6, 2020

An artist’s impression of Kataigidodon venetus. Image credit: Ben Kligman / Hannah R. Kligman.

Paleontologists have uncovered a previously unknown species of cynodont that lived during the Triassic period in what is now Arizona, the United States.

Cynodonts (clade Cynodontia), literally meaning dog teeth, were one of the most diverse and successful groups of therapsids.

They first appeared in the Late Permian period, approximately 260 million years ago, but diversified dramatically in the Triassic period.

They include the direct ancestors of mammals, and so might yield clues about how modern mammals came to be as successful as they are.

Scientifically named Kataigidodon venetus, the newly-identified cynodont species lived some 220 million years ago.

“This discovery sheds light on the geography and environment during the early evolution of mammals,” said lead author Ben Kligman, a doctoral student in the Department of Geosciences at Virginia Tech.

“It also adds to evidence that humid climates played an important role in the early evolution of mammals and their closest relatives.”

Kataigidodon venetus was living alongside dinosauromorphs and possibly early dinosaurs related to Coelophysis, and the cynodont was possibly prey of these early dinosaurs and other predators like crocodylomorphs, small coyote-like quadrupedal predators related to living crocodiles.”

The two fossil lower jaws of Kataigidodon venetus were found in the Chinle Formation in the Petrified Forest National Park in Arizona.

“Finding a fossil that is part of Cynodontia, which includes close cousins of mammals as well as true mammals, from Triassic rocks is an extremely rare event in North America,” Kligman said.

“Prior to this discovery, the only other unambiguous cynodont fossil from the Late Triassic of western North America was the 1990 discovery of a braincase of Adelobasileus cromptoni in Texas.”

Because only the lower jaws of Kataigidodon venetus were discovered and are quite small — 1.3 cm (0.5 inches), Kligman and colleagues only have a semi-picture of how the creature looked, roughly 9 cm (3.5 inches) in total body size, minus the tail.

Along with the jawbone fossils, they found incisor, canine, and complex-postcanine teeth, similar to modern day mammals.

“Given the pointed shape of its teeth and small body size, it likely fed on a diet of insects,” Kligman said.

About 220 million years ago, modern day Arizona and Texas were located close to the equator, near the center of the supercontinent Pangaea.

Kataigidodon venetus would have been living in a lush tropical forest ecosystem.

“It likely would have looked like a small rat or mouse,” Kligman said.

“If you were to see it in person you would think it is a mammal.”

paper on the discovery was published in the journal Biology Letters.

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Ben T. Kligman et al. 2020. A new non-mammalian eucynodont from the Chinle Formation (Triassic: Norian), and implications for the early Mesozoic equatorial cynodont record. Biol. Lett 16 (11): 20200631; doi: 10.1098/rsbl.2020.0631

Source: www.sci-news.com/

Kopidosaurus perplexus: Lizard Skull Fossil is New and 'Perplexing' Extinct Species

Wednesday, November 4, 2020

A CT image of the Kopidosaurus perplexus skull in left lateral view. Credit: Simon Scarpetta

In 2017, while browsing the fossil collections of Yale's Peabody Museum of Natural History, University of Texas at Austin graduate student Simon Scarpetta came across a small lizard skull, just under an inch long.

The skull was beautifully preserved, with a mouth full of sharp teeth—including some with a distinctive curve.

Much to Scarpetta's surprise, no one had studied it. Since being discovered in 1971 on a museum fossil hunting trip to Wyoming, the 52 million-year-old skull had sat in the specimen drawer.

"Lizards are small and prone to breaking apart, so you mostly get these individual, isolated fragmented bones," said Scarpetta, who is studying paleontology at the UT Jackson School of Geosciences. "Anytime you find a skull, especially when you're trying to figure out how things are related to each other, it's always an exciting find."

Scarpetta decided to bring the skull back to the Jackson School for a closer look. And on September 2020, the journal Scientific Reports published a study authored by Scarpetta describing the lizard as a new species, which he named Kopidosaurus perplexus.

The first part of the name references the lizard's distinct teeth; a "kopis" is a curved blade used in ancient Greece. But the second part is a nod to the "perplexing" matter of just where the extinct lizard should be placed on the tree of life. According to an analysis conducted by Scarpetta, the evidence points to a number of plausible spots.

Kopidosaurus perplexus skull in left lateral view. Credit: Simon Scarpetta

The spots can be divided into two groups of lizards, representing two general hypotheses of where the new species belongs. But adding to the uncertainty is that how those two groups relate to one another can shift depending on the particular evolutionary tree that's examined. Scarpetta examined three of these trees—each one built by other researchers studying the evolutionary connections of different reptile groups using DNA—and suggests that there could be a forest of possibilities where the ancient lizard could fit.

The case of where exactly to put the perplexing lizard highlights an important lesson for paleontologists: just because a specimen fits in one place doesn't mean that it won't fit equally well into another.

"The hypothesis that you have about how different lizards are related to each other is going to influence what you think this one is," Scarpetta said.

Paleontologists use anatomical details present in bones to discern the evolutionary relationships of long-dead animals. To get a close look at the lizard skull, Scarpetta created a digital scan of it in the Jackson School's High-Resolution X-Ray CT Lab. However, while certain details helped identify the lizard as a new species, other details overlapped with features from a number of different evolutionary groups.

All of these groups belonged to a larger category known as Iguania, which includes a number of diverse species, including chameleons, anoles and iguanas. To get a better idea of where the new species might fit into the larger Iguania tree, Scarpetta compared the skull data to evolutionary trees for Iguania that were compiled by other researchers based on DNA evidence from living reptiles.

Molecular scaffolds used in the study with labelled main sister relationship hypotheses for Kopidosaurus. Credit: Simon Scarpetta.

On each tree, the fossil fit equally well into two general spots. What's more, the lizard groupings in each spot varied from tree to tree. If Scarpetta had just stopped at one spot or one tree, he would have missed alternative explanations that appear just as plausible as the others.

Scarpetta said that Kopidosaurus perplexus is far from the only fossil that could easily fit onto multiple branches on the tree of life. Paleontologist Joshua Lively, a curator at the Utah State University Eastern Prehistoric Museum, agrees and said that this study epitomizes why embracing uncertainty can lead to better, more accurate science.

"Something that I think the broader scientific community should pull from this is that you have to be realistic about your data and acknowledge what we can actually pull from our results and conclude and where there are still uncertainties," Lively said. "Simon's approach is the high bar, taking the high road. It's acknowledging what we don't know and really embracing that."



More information: Simon G. Scarpetta, Effects of phylogenetic uncertainty on fossil identification illustrated by a new and enigmatic Eocene iguanian, Scientific Reports (2020). DOI: 10.1038/s41598-020-72509-2

Journal information: Scientific Reports 

Provided by University of Texas at Austin 

Source: https://phys.org/

Which Jurassic Park Dinosaurs Are Real (And Which Are Made Up)

Tuesday, November 3, 2020

While most of the dinosaurs in the Jurassic Park and Jurassic World films are real, some are enhanced by fiction, and a few are wholly fictitious.

Here's which dinosaurs are real and which are made up in the Jurassic Park and Jurassic World films. Despite the extensive scientific research behind most every Jurassic Park film, and the cooperation of famous paleontologists like James Horner and Robert Bakker, the filmmakers in each Jurassic Park and Jurassic World film definitely took some creative liberties in portraying the dinosaurs on screen, with later films making up new species outright.

Initially, watching a Jurassic Park film began as a cinematic experience that parallels park creator John Hammond's own objectives - to bring dinosaurs back to life, as it were. The marvel factor was always about that simple exchange with the audience. Then as the audience got hungrier for innovation (as Jurassic World states outright), the franchise looked to diversify and make bigger statements with its dinosaurs to appease its audience.

Given that the dinosaurs are the main draw of the film, it makes sense that filmmakers want to make them as cinematically dynamic as possible. For some directors, that necessitated giving some dinosaurs attributes of different species of dinosaurs, if not creating attributes out of whole cloth for the dinosaurs in question. But not until the Jurassic World films did these movies start making up new dinosaur hybrids. In and out of universe, as audiences became more familiar, and perhaps more jaded, with the idea of resurrected dinosaurs, the drive to entertain drove the filmmakers and park owners to create and use fake dinosaur hybrids. These blurred lines make it more important to pick out what is real and what is fake when it comes to the Jurassic Park dinosaurs.

Jurassic Park (1993)

Despite having arguably the biggest impact of all films in the series, the original Jurassic Park features far fewer dinosaurs and the fewest creative liberties regarding the dinosaurs that do appear. But that’s not to say Spielberg and crew didn’t play fast and loose with some of their chosen prehistoric creatures, though overall they followed the best and latest dinosaur science.

For dinosaurs that make relatively small appearances, like Gallimimus and the Triceratops, nothing about their appearance or behavior contradicts the dinosaur research of the early '90s, and even today what is shown of them in the film is consistent with current paleontological discoveries. It’s the more prominently featured dinosaurs that have the most fictionalized abilities, but even then the filmmakers were relatively tame in their liberties. The Tyrannosaurus Rex was a mostly accurate portrayal, though there is currently no evidence its vision was poor and based on movement, and its portrayal as a hunter definitely takes a side in the still-raging debate as to whether it was a predator, a scavenger, or some combination of the two. While it probably didn’t reach the ridiculous speeds of the T. Rex in the film, the bulky T. Rex could still reach decent speeds of about 25 miles per hour for its size, making the portrayal of the T. Rex more an exaggeration than a fabrication.

Other dinosaurs suffer more in the accuracy department. A real Brachiosaurus could not stand on its hind legs as portrayed in the film, and neither was it capable of the complex whale-like vocalizations it employs in the film. Likewise, real Velociraptors were probably feathered, and markedly smaller than their film counterparts, their appearance based more on the closely related and larger Deinonychus dinosaurs. And, while intelligent compared to their prehistoric peers, there is no evidence real raptors possessed a tenth of the intelligence their cinematic counterparts enjoy.

Finally, most paleontologists would agree that the most egregious creative liberties come with the portrayal of Dilophosaurus, who, in one of the film’s most terrifying moments, spits poison at and devours the unscrupulous Dennis Nedry as he attempts to smuggle dinosaur embryos out of the park. In addition to appearing somewhat smaller than an actual Dilophosaurus, the film version of the creature has a massive lizard-like frill and, as mentioned, spits venom, neither of which have any scientific basis whatsoever. But part of the fun of Jurassic Park is speculating on qualities dinosaurs might have had that would not be preserved in the fossil record, so some paleontologists (and most of the audience) are willing to give this film’s liberties a pass.

Jurassic Park: The Lost World (1997)

Jurassic Park: Lost World introduces more new dinosaurs while preserving what becomes the Big Three dinosaurs included in every later Jurassic Park and Jurassic World installment: T. Rex, Triceratops, and Velociraptors. Among the new dinosaurs are Compsognathus, a sort of tiny version of Gallimimus, Mamenchisaurus, another sauropod dinosaur, Pachycephalosaurus, Parasaurolophus, and Stegosaurus. In contrast to the previous installment, these dinosaurs don’t exhibit any abilities or traits unsupported by the paleontological record.

That said, the T. Rex again takes a prominent role in the film, with a T. Rex family seen for the first time, and the male T. Rex going on a rampage in San Diego during the climax of the film. Indeed, the only new dinosaurs that really have a significant impact on the plot is little Compsothagnus, with the new dinosaurs, even included-by-popular-demand Stegosaurus really only functioning as cameos. Within this film, the T. Rex is no more or less accurate than it was in the prior film, and all the other dinosaurs exhibit no traits that egregiously contradict the dinosaur science of the time

Jurassic Park III (2001)

The third, and for a time, final installment of the Jurassic Park franchise features a whole slew of new dinosaurs, as well as most from the previous installments (especially the Big Three: T. Rex, Triceratops, and Velociraptors). This film saw the first appearance of an Ankylosaurus in the franchise, as well as Ceratosaurus, Corythosaurus, and most significantly, a more prominent appearance of the Pterosaur, Pteranadon (which was not overtly inaccurate, but inaccurate in the sense that it is a pterosaur and not a dinosaur per se), and a new carnivorous dinosaur, Spinosaurus.

The Spinosaurus was introduced as a successor to the infamous T. Rex, killing its rival in an early battle and establishing itself as the main dinosaur antagonist. Despite this battle being the focal point of most fans ire, Spinosaurus would not have been able to kill the T. Rex, if for no other reason than Spinosaurus and T. Rex were separated by several million years, Spinosaurus living in the Jurassic period and T. Rex in the Cretaceous period. But supposing the two did end up fighting each other, Spinosaurus’ long snout indicates it most likely subsisted on a diet of fish, making it a poor opponent of the decidedly better-equipped T. Rex. 

Jurassic World (2015)

Jurassic World was the first film in this series to create completely new dinosaurs, specifically with the new carnivorous antagonistic force, the Indominus Rex. Indominus Rex is a hybrid of a T. Rex and Velociraptor, with DNA from cuttlefish, tree frogs, and a smattering of other carnivorous dinosaurs. It can camouflage itself, has longer arms than the T. Rex, and unlike the T. Rex or the Velociraptor, it can run on all fours. Indominus Rex is created by Dr. Henry Wu in response to the concerns of the Masrani corporation that park-goers are getting bored with resurrecting actual dinosaurs that actually existed, and creating a new hybrid dinosaur would excite more interest. 

But, like any Jurassic Park installment, the film introduces a new crop of real dinosaurs in addition to the recurring dinosaurs (including, of course, the Big Three: Triceratops, T. Rex, and, playing a much more major role this time, Velociraptors). Among the new creatures that actually existed are the carnivore Baryonyx, and pterosaur Dimorphodon, and the franchise’s first mosasaur, Mosasaurus. That said, the mosasaur's size is inconsistent throughout the film (ranging from easily able to swallow a shark, to just barely able to bite human-sized creatures), and the pterosaurs are portrayed as much stronger and more agile flyers than they actually were. The film also originally included a prominent role for another hybrid, the Stegoceratops, but its appearance was reduced to a computer screen in the final film. 

Jurassic World: Fallen Kingdom (2018)

In addition to Indominus Rex, InGen geneticist Dr. Wu clearly did not learn his lesson and proceeded to create a hybrid of Indominus and Velociraptor called Indoraptor. Dr. Wu did have a different purpose in creating this hybrid, intending Indoraptor to be a weapon rather than a tourist attraction, but the experiment predictably went badly wrong over the course of the film. Looking much more like a raptor than Indominus Rex, Indoraptor can also alternate between walking on four and two limbs, with long, human-like arms, and black skin, rendering it almost invisible in the dark.

To its credit, Jurassic World 2 doesn’t overly indulge in mutant dinosaur making - and thankfully Jurassic World 3 also won't include more dinosaur hybrids - and included most dinosaurs from the previous films, as well as introducing a few not seen in the franchise before. Fallen Kingdom introduced carnivores Allosaurus and Carnotaurus, as well as herbivore Stygimoloch. The latter is actually more of a controversial inclusion than it first appears, as most paleontologists consider Stygimoloch a juvenile Parasaurolophus rather than its own distinct species. 

But Why Make Up Dinosaurs At All?

The original series, to its credit, never made up a new dinosaur, instead exploiting the general public's unfamiliarity with most dinosaurs to dazzle their audience with a new dinosaur or prehistoric creature in each installment. There are so many dinosaurs most regular filmgoers have no idea exist, that almost seem made up with their diverse and baffling physiology, it seems strange that the filmmakers of the new crop of Jurassic Park films seem to think they need to make up dinosaurs to make their films more interesting and attractive. The original sometimes played fast and loose with true dinosaur physiology, but never saw the need to make up a species outright. Why do these younger films indulge so freely in that fantasy, with so many fantastic and bizarre real dinosaurs at their fingertips?

The filmmakers' stated intention was to show how scientific hubris has gone beyond resurrecting the dinosaurs that actually existed and make their theme park more successful and exciting by creating animals that the world has truly never seen before. That said, in doing so they might unconsciously betray a similar lack of trust in their audience that the characters who create the fake dinosaur hybrids exhibit: audiences have been so familiarized with once exotic species of dinosaurs, that the filmmakers don’t trust that simply introducing a hitherto obscure species of dinosaur will capture audiences' attention the way they did back in 1993. They need to up the ante of the original film trilogy’s whole “playing God” themes by having scientists create sexier, but incredibly dangerous hybrid creatures for shallow reasons. 

But that often leads to nonsensical character decisions which make the creators of said dinosaurs look like morons. In-universe, they knew the consequences of failing to carefully contain real dangerous dinosaurs like the T. Rex and Velociraptors: why would they take the risk of creating an entirely new dinosaur more dangerous and with more specialized abilities than the existing dinosaurs? To chalk it up entirely to hubris and capitalism seems like a cop-out: Hammond and his crew ultimately committed a phenomenally stupid and dangerous act by resurrecting dinosaurs, but they had more in their defense, what with its potential benefits to the scientific community and the possibility of groundbreaking new discoveries about the earth’s past.

Creating a whole new dinosaur hybrid that’s also incredibly dangerous offers no such excuses or possible benefits. Instead, it's creating something new and dangerous simply because “it’s cool," and might make more money and garner more attention (which results in more money). Granted, plenty of people are primarily motivated to do stupid things for the sake of profit, but to have that be the scientists only motivation for creating such an incredibly dangerous hybrid dinosaur like Indominus Rex is shallow and lacking in any type of sense that this is an action an actual human would persuade themselves is reasonable. Not that it couldn’t happen in real life, but the decision really needed more nuance to be accepted as justifiable in and out of the world of the Jurassic Park/Jurassic World franchise.

Source: https://screenrant.com/

Filikomys primaevus: Rodent-Like Mammal from Cretaceous Period Lived in Colonies

Wednesday, November 4, 2020

Filikomys primaevus’ powerful shoulders and elbows suggest it was a burrowing mammal. Art by Misaki Ouchida.

Filikomys primaevus, a new genus and species of multituberculate mammal that lived during the Late Cretaceous period, has been identified from multi-individual aggregates of skulls and skeletons found at a dinosaur nesting site in Montana, the United States. The well-preserved fossils indicate that Filikomys primaevus engaged in multi-generational, group-nesting and burrowing behavior, representing the first example of social behavior in a Mesozoic mammal.

Multituberculates were mostly small-bodied, omnivorous or herbivorous mammals that lived between 166 and 35 million years ago, from the Middle Jurassic to the late Eocene.

Most species of multituberculates are generally recovered as loose teeth; preserved skulls and jaws are rare except in Mongolia.

They are known from North America and Europe — which were a single continent until the early Eocene — in the uppermost Triassic to the lower Oligocene, and from northern Asia in the upper Cretaceous and Paleocene.

“Multituberculata is one of the most ancient mammal groups, and they’ve been extinct for 35 million years, yet in the Late Cretaceous they were apparently interacting in groups similar to what you would see in modern-day ground squirrels,” said lead author Luke Weaver, a graduate student in the Department of Biology at the University of Washington.

An artistic reconstruction of a social group of Filikomys primaevus in a burrow while dinosaurs roam above. Image credit: Misaki Ouchida.

Filikomys primaevus roamed Earth during the Cretaceous period, about 75.5 million years ago.

The fossilized skulls and skeletons of at least 22 individuals were recovered from a well-known dinosaur nesting site called Egg Mountain in western Montana.

They were typically clustered together in groups of two to five, with at least 13 individuals found within a 30 m2 area in the same rock layer.

Based on how well preserved the fossils are, the type of rock they’re preserved in, and Filikomys primaevus’ powerful shoulders and elbows, Weaver and colleagues hypothesize these animals lived in burrows and were nesting together.

Furthermore, the ancient animals were a mixture of multiple mature adults and young adults, suggesting these were truly social groups as opposed to just parents raising their young.

“Because humans are such social animals, we tend to think that sociality is somehow unique to us, or at least to our close evolutionary relatives, but now we can see that social behavior goes way further back in the mammalian family tree,” Weaver said.

Skeletal elements of the five Filikomys primaevus individuals from Egg Mountain, Montana, the United States. Scale bars – 1 cm. Image credit: Misaki Ouchida / Weaver et al., doi: 10.1038/s41559-020-01325-8.

Previously, paleontologists thought social behavior in mammals first emerged after the mass extinction that killed off the dinosaurs, and mostly in the Placentalia — the group of mammals humans belong to, which all carry the fetus in the mother’s uterus until a late stage of development.

But Filikomys primaevus shows mammals were socializing during the Age of Dinosaurs, and in an entirely different and more ancient group of mammals — the multituberculates.

“These fossils are game changers,” said senior author Dr. Gregory Wilson Mantilla, a researcher in the Department of Biology at the University of Washington and the Burke Museum of Natural History & Culture.

“As paleontologists working to reconstruct the biology of mammals from this time period, we’re usually stuck staring at individual teeth and maybe a jaw that rolled down a river, but here we have multiple, near complete skulls and skeletons preserved in the exact place where the animals lived.”

“We can now credibly look at how mammals really interacted with dinosaurs and other animals that lived at this time.”

The discovery of Filikomys primaevus is reported in a paper in the journal Nature Ecology & Evolution.

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L.N. Weaver et al. Early mammalian social behaviour revealed by multituberculates from a dinosaur nesting site. Nat Ecol Evol, published online November 2, 2020; doi: 10.1038/s41559-020-01325-8

Source: www.sci-news.com/

Buriolestes schultzi: The First Complete Dinosaur Brain Has Been Perfectly Reconstructed

Wednesday, November 4, 2020

The meat eater walked the Earth 233 million years ago. (Credits: Marcio L Castro / SWNS)

The first complete brain of an dinosaur has been unveiled by scientists. Weighing less than a pea, it belonged to a meat eater that walked the Earth 233 million years ago. Amazingly, the ferocious beast’s perfectly preserved skeleton included the braincase – enabling a precise reconstruction of its grey matter. Stunning computer images reveal regions involved in coordination, sight, smell, intelligence – and even reproduction. The remarkable discovery sheds fresh light on the evolution of the biggest land animals that ever lived.

The Buriolestes schultzi dinosaur whose brain has been visualised by scientists. (Credits: Marcio L Castro / SWNS)

Named Buriolestes schultzi, it is an ancestor of the long necked sauropods – the most colossal of them all. Palaeontologist Dr Rodrigo Muller, of the Federal University of Santa Maria, Brazil, told South West News Service: ‘The brain is a window into its behaviour – and intelligence.’ The findings show Buriolestes was an athletic and skilful hunter. It had better eyesight than smell. And it was not as smart as T Rex – or today’s birds. The pet sized creature weighed about a stone. It was small but vicious – similar in stature to a fox. Its sharp, curved teeth and claws would have ripped lizards and primitive mammals to shreds – as well as the young of other dinosaurs. It also ate insects. Buriolestes was hunted itself – by ‘killing machine’ Gnathovorax. The ten foot tall dinosaur was the apex predator of the period. Dr Muller said: ‘The brain of Buriolestes is relatively small, weighing about 1.5 grams (0.05oz) – which is slightly lighter than a pea. The shape is primitive, resembling a crocodile’s. ‘In addition, the presence of well developed structures in the cerebellum indicates the capability to track moving prey. ‘Conversely, the olfactory sense was not good. Buriolestes hunted and tracked prey based on sharp eyesight rather than smell.’ Soft organs, such as the brain, don’t survive fossilisation. So his team used CT (computed tomography) scans to peer into the internal cranial cavities. He explained: ‘We access isolated sections of the skull, filling the gaps of each. When we put these regions together we get a 3D representation of the space – or endocast.’

Scientist Rodrigo Temp Muller (Credits: Rodrigo Temp Muller / SWNS)

The X-rays mapped the cerebellum that controls co-ordination, balance and posture as well as the optical lobe – the visual processing centre. They also revealed the olfactory bulb and tract responsible for smell and the cerebrum that triggers intelligence and conscious thoughts. The pituitary gland at the base of the brain was drawn up too. It produces hormones that fuel growth, blood pressure – and reproduction. Dr Muller said: ‘The technique demands well-preserved braincases, which envelopes the tissues. ‘It is the upper and back part of the skull, which forms a protective case around the brain.’ He added: ‘Buriolestes dates back to the dawn of the dinosaurs. So far, complete braincases from the oldest dinosaurs worldwide were unknown. It has helped unlock the secrets of its way of life.’ The bizarre animal measured about four feet from head to tail. It had a long neck, razor sharp teeth and three long claws on each of its four limbs. It ran on two legs. Its remains were unearthed in 2015 during an expedition to the rainforest of southern Brazil led by Dr Muller. He said: ‘It is a well known dinosaur graveyard. The place is a ravine with other fossilised skeletons in a farm.’ Buriolestes lived during the Triassic, when South America was still part of the super-continent called Pangaea.
 

The ferocious beast’s perfectly preserved skeleton included the braincase (Credits: Marcio L Castro / SWNS)

Despite being a carnivore, it is the earliest member of the plant-eating sauropods – that weighed up to 100 tons and reached 110 feet long. Dr Muller said: ‘The reconstruction allows us to analyse the brain evolution of the biggest land animals that ever lived.’ One of the most conspicuous trends is the increase of the olfactory bulbs. These were relatively small in Buriolestes – but became very large in sauropods. Dr Muller explained: ‘The development of a high sense of smell could be related to the acquisition of a more complex social behaviour – seen in several vertebrate groups. ‘Alternatively, it has also been observed high olfactory capabilities played an important role in foraging – helping animals to better discriminate between digestible and indigestible plants. ‘Finally, another putative explanation for the better smell in sauropods relies on the capability to pick up the scent of predators.’ The pituitary gland is also related to size – and is proportionally small in Buriolestes, On the other hand, it is very large in the giant sauropods. Dr Muller said: ‘Hence, we can associate the development of the gland with the gigantism of sauropods.’ The study published in the Journal of Anatomy also calculated the intelligence of Buriolestes based on brain volume and body weight.

Computer images reveal regions involved in coordination, sight, smell, intelligence – and even reproduction. (Credits: Marcio L Castro / SWNS)

Dr Muller said: ‘The values obtained are higher than that of the giant sauropods – like Diplodocus and Brachiosaurus – suggesting a decrease in brain size compared to body. ‘It changed across the time, not only in general morphology, but also in the neurological functions. The brain anatomy changes together with the body plan of these animals. ‘It is interesting because several other lineages present an increase in this phenomenon – known as encephalization – through time. ‘Nevertheless, the ‘cognitive capability’ of Buriolestes is lower than that of theropod dinosaurs, the lineage that includes T Rex and Velociraptor of Jurassic Park fame – and birds.’ In the view of most experts, birds are ‘living dinosaurs’. Their key skeletal features – as well as nesting and brooding behaviours – actually arose first in some dinosaurs.

Source: https://metro.co.uk/

5-Million-Year-Old Honey Badger-Like Animal Discovered

Tuesday, November 3, 2020

Honey Badger (Mellivora capensis). Credit: Jaffacity CC BY-SA 4.0

New research reports on discovery of 5-million-year-old honey badger-like animal from West Coast of South Africa.

Five million years ago, dangerous carnivores — such as giant wolverines and otters, bears, sabertooth cats, and large hyaenids — prowled the West Coast of South Africa. Today we can confirm that, among them, fearlessly roamed a smaller relative of the living honey badger.

New research published in Journal of Vertebrate Paleontology by paleontologists Alberto Valenciano Vaquero (Iziko Museums of South Africa, the University of Cape Town, South Africa, and University of Zaragoza, Spain) and Romala Govender (Iziko Museums of South Africa, Research and Exhibitions) report on the discovery of a relative of the living honey badger from the early Pliocene locality of Langebaanweg (West Coast Fossil Park, South Africa). Besides this honey badger-like animal, this 5.2 million years locality has yielded one of the world’s richest and best-preserved mammal assemblages of this time period, including saber-toothed cats, bears, hyaenas, jackals, mongoose, as well as relatives of the living giraffes, elephants, rhinoceroses, wild pigs, and a variety of birds, fishes, and marine mammals.

Five million years ago, dangerous carnivores – such as giant wolverines and otters, bears, sabertooth cats, and large hyaenids – prowled the West Coast of South Africa. Today we can confirm that, among them, fearlessly roamed a smaller relative of the living honey badger. Credit: Romala Govender

Living honey badger (also known as ratel) (Mellivora capensis) belong to the mustelid family which includes weasels, otters and badgers. They live in most of sub-Saharan Africa and East Asia, including India. Despite its relatively small size (9-14 kg), honey badgers are one of the most aggressive and fierce animals in the world. “Even large carnivores, such as leopards, hyenas, and lions stay out of their way,” says Valenciano, lead author of this research. Honey badgers are equipped with sharp teeth and long claws to help capture prey, but they also feed on berries, roots and bulbs, insects and small vertebrates.

The extinct honey badger from Langebaanweg (Mellivora benfieldi) was originally described by Brett Hendey more than 40 years ago and was based on a few fragmented mandibles. “The new honey badger fossils we describe triple the number of known fossils and gives us a unique glimpse into its lifestyle and relationship to other similar mustelids. These new fossils demonstrate that this South African species is distinct from the late Miocene forms from Central Africa (Howellictis) and East Africa (Erokomellivora), as well as from the extant honey badger,” says Valenciano.

This work deals with the evolution of this fascinating group of mustelids in Africa during the last seven million years and confirm the existence of a unique group named Eomellivorini. Although the ratel represents the single living member of its subfamily of mustelids, they were much more diverse in the past. In fact, Valenciano and Govender suggest the existence of two distinct groups of mustelids: the mellivorini (comprising the living ratel, the one from Langebaanweg and several others ratel-like relatives), as well as the Eomellivorini which are characterized by gigantic proportions.

“Identification of the Eomellivorini, which include Eomellivora (from the northern continents) and Ekorus (from Africa), identifies a group of giant mustelids related to the living ratel that were adapted for pursuit unlike any mustelids seen today, and may have evolved at a time when cats of this size were rare or non-existent,” says Prof. Lars Werdelin (Swedish Museum of Natural History), a leading expert on carnivores who was not involved in the research.

This research also shows that the Langebaanweg honey badger was slightly smaller than the ratel, but that like its modern relative, it was also an opportunistic carnivore with digging abilities.

“The Langebaanweg fossils are at a crossroads of climate and environmental change giving us insight into how animals adapted to these changes as well as insight into carnivore evolution in southern Africa,” Dr. Govender says. UCT Palaeontologist Anusuya Chinsamy-Turan, who was not involved in the research, says “This is an incredible discovery! Can you imagine, if it were not for the fossils at Langebaanweg we would have absolutely no idea of the rich biodiversity that once existed along the West Coast of South Africa.”

Ongoing research in the other carnivore mammals from Langebaanweg will expand our knowledge on these awesome extinct animals.

Reference: “New Fossils of Mellivora Benfieldi (Mammalia, Carnivora, Mustelidae) from Langebaanweg, ‘E’ Quarry (South Africa, Early Pliocene): Re-Evaluation of the African Neogene Mellivorines” by Alberto Valenciano and Romala Govender, 2 November 2020, Journal of Vertebrate Paleontology.
DOI: 10.1080/02724634.2020.1817754

Source: https://scitechdaily.com/

Jurassic Park Sequels: 5 Things They Got Right (& 5 Things That Missed The Mark)

Saturday, October 31, 2020

No sequel will match the dinosaur magic of Steven Spielberg's original Jurassic Park, but its franchise follow-ups have their breathtaking moments.

Between the groundbreaking, masterfully crafted original Jurassic Park movie helmed by Steven Spielberg and the lukewarm, crowd-pleasing, semi-meta reboot Jurassic World, two direct sequels were produced: The Lost World, directed by Spielberg himself, and Jurassic Park III, directed by Joe Johnston. The response to both movies paled in comparison to their predecessor’s record-setting box office numbers and universal critical acclaim.

But after the heartbreaking misfire that is Jurassic World: Fallen Kingdom, fans have realized they may have treated The Lost World and Jurassic Park III a little too harshly. These sequels still have their problems, but there's a lot to love about them.

10 - Right: The Pterodactyls In Jurassic Park III

Joe Johnston got his start working on the Star Wars crew, putting together the miniature effects that make up the original trilogy’s biggest set pieces, so it’s hardly surprising that he brought some incredible new effects to the table when he helmed Jurassic Park III.

The director took the coolest dinosaur that had yet to be featured in the franchise — pterodactyls, the terrifying flying predators — and put them front in center. Every scene featuring the pterodactyls is spectacular, especially the misty high-altitude sequences.

9 - Missed The Mark: Using The Dinosaurs As A Gimmick

The dinosaurs were used sparingly in Jurassic Park to build suspense and mystique and they were depicted as awe-inspiring forces of nature that didn’t always pose a threat. But in the sequels, the dinosaurs were mostly reduced to ravenous killing machines who appeared in as many scenes as possible.

Of course, dinosaurs are the bread and butter of this franchise, but that doesn’t mean the movies should just have wall-to-wall dinosaur eye candy. Telling a compelling story is much more important — the dinosaurs are the cherry on top.

8 - Right: The Lost World’s VFX

The visual effects in Jurassic Park were truly groundbreaking, and although The Lost World overused them, they were just as slickly designed and sharply rendered as the effects in the original.

Unfortunately, the same cannot be said of Jurassic Park III, whose effects are pretty low-rent. It could’ve been because the studio slashed the budget or just because the VFX artists weren’t as good.

7 - Missed The Mark: Betraying Legacy Characters

Ian Malcolm takes center stage in The Lost World and Alan Grant returns to the spotlight in Jurassic Park III, but despite having those names and the talented actors behind them, they don’t really feel like those characters.

The characterization in Jurassic Park is so sharp in making Malcolm a wisecracking nuisance with irresistible charm and Grant a cynic who needs to open up, but The Lost World made Malcolm a bumbling moron and Jurassic Park III made Grant a soft Indiana Jones whose fedora does the legwork for his character development.

6 - Right: T. Rex On The Loose In San Diego

While Jurassic World: Fallen Kingdom made the strange choice to move all the dinosaurs to the mainland for the big finale and then confine them all to a single house, The Lost World went all-in with the same midpoint twist and let a T. rex loose on the streets of San Diego.

This allowed Spielberg to play in the sandbox of an entirely different type of monster movie, essentially Godzilla with a T. rex instead of a nuclear sea monster.

5 - Missed The Mark: Alan Has A Bad Dream

There’s a heavily memed scene in Jurassic Park III in which Alan Grant is sleeping on a plane, wakes up to find that the pilots are gone, and then turns his head to see a velociraptor standing next to him. Instead of attacking him, the raptor says, “Alan!,” and he jolts awake from a bad dream.

This scene plays more like a gag from Scary Movie than a genuine moment from the same narrative timeline as Jurassic Park’s raptors-in-the-kitchen suspense sequence.

4 - Right: The Lost World’s RV Set Piece

Perhaps the most exciting set piece from the Jurassic Park sequels is the scene in The Lost World in which some angry dinosaurs knock the team’s mobile lab over the edge of a cliff and it hangs by a thread.

As the RV precariously hangs over a giant drop into some nondescript jungle, the characters desperately try to climb up to safety while avoiding the attacking dinos.

3 - Missed The Mark: A Bunch Of Terrible Characters In Jurassic Park III

Apart from Sam Neill’s dependable performance as Alan Grant and William H. Macy playing one of his classic loser roles as Paul Kirby, most of the characters in Jurassic Park III are terrible. They’re all badly written and some of them are actually bad people.

Amanda Kirby screams through the whole movie, which gets irritating in a hurry, while Billy Brennan endangers everyone’s lives and breaks up a dinosaur family that was minding its own business by stealing raptor eggs.

2 - Right: Jurassic Park III’s Lean Script

Some of the effects in Jurassic Park III are shaky and plenty of its characters are unlikable, but it does have a lean script going for it. It wastes no time setting up each scene and doesn’t let the pesky plot get in the way of the action.

The script is partly credited to Alexander Payne and Jim Taylor, the writing team behind such gems as Election and Sideways, so it’s hardly surprising that it’s well-paced and well-structured.

1 - Missed The Mark: Never Reuniting The Original’s Trio

Colin Trevorrow is set to fix this egregious error in Jurassic World: Dominion, finally reuniting Jurassic Park’s holy trinity of Sam Neill, Laura Dern, and Jeff Goldblum as Drs. Grant, Sattler, and Malcolm. None of the previous sequels featured all three. The Lost World only featured Goldblum, while Neill starred in Jurassic Park III and Dern phoned in a cameo appearance in the most literal sense.

It’s like if, after the original 1977 Star Wars movie brought Luke, Leia, and Han together, The Empire Strikes Back only featured a watered-down version of Han and Return of the Jedi only featured a watered-down version of Luke and a shoehorned-in phone call with Leia.

Source: https://screenrant.com/

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