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Feathers Evolved 80 Million Years Before Birds Appeared

Friday, June 7, 2019

Image: Reconstruction of the studied pterosaur, with four different feather types over its head, neck, body, and wings, and a generally ginger-brown color. Credit: Reconstruction by Yuan Zhang.

Scientists at the University of Bristol have found evidence of feathers in a dinosaur that existed 80 million years before birds, a discovery that changes how we look at dinosaurs, birds and feathers themselves.

The research, a combination of paleontology and molecular developmental biology, was published in the journal Trends in Ecology & Evolution.

A pair of pterosaur fossils—discovered earlier this year in China—showed signs of both down feathers over the body and long, vaned feathers on the wings. Pterosaurs, a group of bird-like flying reptiles commonly referred to as pterodactyls, lived 228 to 66 million years ago during the Triassic and Cretaceous periods.

The oldest known bird is Archaeopteryx, which is believed to have lived in southern Germany 150 million years ago during the late Jurassic period.

Feathers arose 250 to 230 million years ago, during the Early Triassic, when life was recovering after the end-Permian mass extinction and new species were evolving to fill ecological voids, the study revealed. This is nearly 80 million years before the first bird, a surprise to many researchers who believed that feathers helped drive the success of avian fauna.

"A combination of new fossil evidence and new thinking in genetics of development show us that feathers are not unique to birds, but to a much larger group that includes dinosaurs and pterosaurs. This means feathers actually originated much earlier than thought, and that the original function of feathers was insulation, not flight," Mike Benton, lead author of the study and a professor of Vertebrate Paleontology at the University of Bristol's School of Earth Sciences, explained to Laboratory Equipment. "We are keen to examine a greater range of dinosaurs and pterosaurs to see how widespread the different feather types are, and what we can learn about feather function and color from the fossils."

The findings add to the growing body of work suggesting that birds and dinosaurs are closely related on the evolutionary tree.

In the early 1990s, researchers discovered that some dinosaurs possessed feathers. The first dinosaur fossils to reveal evidence of feathers were approximately the same age as the earliest birds. Previously, it was believed that dinosaurs were most closely related to reptiles.

"This discovery means that the evolutionary selective pressure to evolve feathers was nothing to do with size reduction, raised warm bloodedness and activity levels for flight (which was happening in the Jurassic before Archaeopteryx emerged), but it was all about recovery of life from the devastating end-Permian mass extinction, and a re-tooling of the main land animals to walk upright, be warm-blooded and move faster," Benton said.

Source: www.laboratoryequipment.com

10 Things From Jurassic Park That Kids These Days Won't Understand

Thursday, June 6, 2019

In the summer of 1993, Steven Spielberg sent Jurassic Park stomping into theaters, and audiences weren’t prepared for its exciting mix of action, thrills, adventure, and horror. The king of blockbusters like E.T. and Jaws had managed to make a film that had heart as well as bite, and the movie based on Michael Crichton's best-selling novel about dino mutation became a mega hit.

But much like comparing a T-Rex to the Indominus Rex of Jurassic World, there are aspects of the first entry in the Jurassic Park franchise that seem a little antiquated and a little archaic when juxtaposed against their newer counterparts. Kids today, raised on blockbusters with non-stop action, excessive CGI, and mile-a-minute thrills may be confused by elements of this masterpiece for no other reason than it’s from a different time period in cinema history. Here are 10 things from Jurassic Park that kids these days won’t understand.

10 WHAT A COLOSSAL HIT IT WAS

Steven Spielberg, king of blockbusters had another hit on his hands when he welcomed visitors to Jurassic Park. He ushered in an era of colossal action movies that, unlike the bullet drenched versions of the 80s had heart and complex storytelling. Only James Cameron would match his similar stance on combining action with humanity.

In an era like today, where kids go to see every new Marvel movie that comes out, expecting to be blown away by movies that blow past the 1 billion dollar mark, the significance of a movie like Jurassic Park is lost. It was the first of its kinds, inspiring many duplicates, each never quite as good as the original.

THE SIGNIFICANCE OF EARLY CGI

Prior to Jurassic Park, Steven Spielberg had mostly dealt with practical effects and animatronics in his monster features. Jaws was not a CGI shark, he was an actual giant animatronic puppet. James Cameron had made some headway with Judgement Day, but CGI effects were still in their infancy.

But Spielberg wanted to try something new - him and his crew of practical effects wizards devoted themselves to learning the latest advancements in computer graphics, rendering some of the best early examples of CGI that still hold up to this day. It’s what lead to the majority of dinosaurs being entirely CGI in Jurassic World.

EMOTIONAL IMPACT VS VISUAL PAYOUT

The reason that Steven Spielberg is considered one of the greatest filmmakers of all time is for many of the techniques he used in Jurassic Park. He shot from the POV of the terrified visitors to the park, highlighting the epic scale of the dinosaurs. It also grounded the emotions of the reactions of the actors, even if all they were looking at was CGI.

Contrast this with Jurassic World  or Jurassic: Kingdom which, when given the option to either focus on the impact of dinosaurs on humans or the dinosaurs themselves, always went for the “cool” shot of dinosaurs, utilizing drone cameras to show the epic sprawl of a dino battle while completely eliminating any of the emotional repercussions. It’s certainly awesome, but the audience isn’t scared.

THE OUTDATED COMPUTER INTERFACES

Jurassic Park is controlled entirely by computers, which isn’t surprising to any kid today. They’re familiar with smart technology, and devices synced together to be controlled by a remote one.  What they won’t be as familiar with is the outdated computer interfaces throughout the film.

Characters operate big clunky Macintosh computers, with black screens and green lettering. The imaging is very primitive, with significant lag time as the images load. Kids won’t even be able to identify the technological goals of the characters simply because they aren’t using technology they recognize to accomplish them. When Lex uses her “hacking” skills to access the park’s central mainframe, kids today may be wondering if she’s playing a video game.

THE LACK OF DINO MUTATIONS

If kids today have grown up on a steady diet of Jurassic World and Jurassic Kingdom, chances are they’ve come to expect a little more from their dinosaurs. They’re expecting not just a simple T-Rex, but a T-Rex mixed with something else. As Bryce Dallas Howard so cavalierly says in Jurassic World, “No one’s impressed by dinosaurs anymore.”

It’s at this point that kids these days won’t find the velociraptors or the T-Rex terrifying because it isn’t an Indominus Rex, a dangerous cross between the two, and infused with other reptile DNA, not just frogs. This means it can turn itself invisible, which makes it a much scarier threat to them.

THE PHONE LINES BEING CUT

At a critical juncture in the film all systems go offline, courtesy of Dennis Nedry who needs the systems down so he can steal several dinosaur embryos to sell them for a big profit. Unfortunately, this cuts the power to the park and to the dinosaur paddocks, allowing the creatures to roam free unhindered.

The phones lines are nonoperational, which may make little sense to kids today who haven’t ever used a landline like the ones in the film. They’ve also probably never operated the payphone that Nedry uses to connect with his contact, or the significance of not being able to reach the satellite phones in the car (which incidentally don’t run on Bluetooth).

THE ABSENCE OF CELL PHONES

Like so many horror films where the heroes having cell phones might have prevented them from being slaughter, Jurassic Park doesn’t bank on your smartphone saving the day. But it isn’t just a narrative imperative to ensure the stakes of the victims are raised; it’s because cellphones weren’t nearly as common place back then, even for billionaires like John Hammond.

Versions of them existed, but they’re literally referred to as “dinosaurs” now, and were obnoxiously bulky and hard to use. Today, children might very well wonder the significance of phone lines being down in a movie when the presence of cell phones would make the anxiety levels dissipate considerably.

HOW BIG OF A DEAL THE T-REX REALLY WAS

The scene involving the two park cars and the T-Rex escaped from its paddock makes for some of the most tense filmmaking ever witnessed. Part of this is due to the film direction and the actors, and part of it’s due to the largest animatronic that had ever been made for cinema. Although not quite as large as a real T-Rex, the one made for the film was nearly as tall as a house.

What made the T-Rex so impressive wasn’t simply its size and detail, but the fact that it had eyes that actually dilated when light was pointed at them, such as the scene when Lex directs the beam of her flashlight at it.

THE VELOCIRAPTORS IN THE KITCHEN

One of the most iconic scenes in the film involves Tim and Lex, a kitchen, and two velociraptors. The children try to remain as quiet as possible without alerting the raptors to their presence, but the scene somehow makes you feel as though their every breath could seal their fate. Part of this is because some of the raptors are real animatronics and some of them are CGI.

The animatronic raptors are part machine, part puppet, and controlled by men with armatures in suits. They are involved for close up shots and anything that doesn’t involve fast movement. They’re perfectly blended with the CGI raptors, to the point where you can’t tell them apart, which was incredibly advanced for its time.

THE FACT THAT PEOPLE LOOKED LIKE PEOPLE

Kids these days watch any movie similar to Jurassic Park and take for granted the fact that every person in the film is coiffed and manicured to perfection. In Jurassic World, for instance, Bryce Dallas Howard is made up throughout the film (and remains in heels for the length of it), while Chris Pratt is chiseled from a piece of fossilized amber.

In Jurassic Park, people looked like people. Dr. Alan Grant was not a hunk. Dr. Sattler wasn't a dewy damsel. And the kids spend a lot more time looking completely frazzled than they do adorable or otherwise. Everyone wore functional clothing, and didn't mug for the camera (with the exception of Dr. Ian Malcolm, but they gave him a whole other movie to do that).

Source: https://screenrant.com

Why Giant Beavers Went Extinct 10,000 Years Ago

Thursday, June 6, 2019

Giant beavers, about as large as a modern-day bear, ate aquatic plants before they went extinct after the last Ice Age. Image credit: Luke Dickey.

Giant beavers (members of the genus Castoroides) inhabited North America throughout the mid- to late Pleistocene. They went extinct along with dozens of other megafaunal species at the end of the last Ice Age, approximately 10,000 years ago. Now a team of researchers in Canada has uncovered a possible reason of their extinction: vanishing food source. More importantly, the scientists have discovered that these enormous rodents did not eat wood — a distinct divergence from their dentally-endowed descendants.

Tessa Plint of Heriot-Watt University and her colleagues from the University of Western Ontario, Yukon Palaeontology Program and the Canadian Museum of Nature used stable isotopes of fossil bones and teeth to determine the diet of the now-extinct giant beavers.

The researchers found that the beavers ate submerged aquatic plants (macrophytes).

This diet made the rodents, which weighed approximately 100 kg, highly dependent on wetland habitat not only for shelter from predators but also for food.

“We did not find any evidence that the giant beaver cut down trees or ate trees for food,” Plint said.

“Giant beavers were not ‘ecosystem-engineers’ the way that the North American beaver is.”

Beavers (members of the genus Castor) and giant beavers actually co-existed for tens of thousands of years in North America during the Pleistocene epoch before the latter went extinct.

After the last Ice Age, the ice sheets retreated and the climate became much drier. This climate change was bad news for giant beavers.

“The ability to build dams and lodges may have actually given beavers a competitive advantage over giant beavers because it could alter the landscape to create suitable wetland habitat where required. Giant beavers couldn’t do this,” said Professor Fred Longstaffe, from the University of Western Ontario.

“When you look at the fossil record from the last million years, you repeatedly see regional giant beaver populations disappear with the onset of more arid climatic conditions.”

The findings were published in the journal Scientific Reports.

_____

Tessa Plint et al. 2019. Giant beaver palaeoecology inferred from stable isotopes.Scientific Reports 9, article number: 7179; doi: 10.1038/s41598-019-43710-9

Source: www.sci-news.com

Dinosaurs Return to Smithsonian Fossil Hall After 5-Year Renovation

Thursday, June 6, 2019

After five fossil-less years, T. rex is roaring back to the Smithsonian.

The David H. Koch Hall of Fossils -- Deep Time at the Smithsonian National Museum of Natural History in Washington, DC, reopened June 8, after being closed for the past five years.

The exhibit features over 700 fossils ranging from giants like Tyrannosaurus rex to fossilized animals and even plants and bugs. CNN got a preview of the 31,000-square-foot exhibit.

"The exhibition tells the story of 3.7 billion years of life on Earth, highlighting the connections among ecosystems, climate, geological forces and evolution and encouraging visitors to understand that the choices they make today will have an impact on the future," according to the museum.

The hall aims to "chronicle of the entire history of life" by illustrating the origins, evolution and changing surroundings of different species, according to a museum press release. The exhibit's themes include "All Life is Connected," "Evolution," "Ecosystems Change," "Earth Processes," "Extinction," and "Age of Humans and Global Change."

Visitors can learn "about the myriad ways in which humans are causing rapid, unprecedented change to the planet" in the Warner Age of Humans Gallery, which was made in conjunction with the Anthropocene Advisory Committee, a panel of climate change scholars and educators. Museum guests can also watch scientists prepare fossils in the FossiLab, per the release.

Kirk Johnson, Sant Director of the National Museum of Natural History, said that while the interactive exhibit provides an experience steeped in the past, it also addresses questions about Earth's current and future challenges.

"Visitors to the new hall will go on a voyage like no other—a journey that begins in the past and ends in the future," Johnson said in a statement. "Along the way, they will experience the history of life on Earth—a story told through extraordinary fossils and engaging interactive exhibits."

"Visitors will also be called upon to consider the very real challenges our planet faces and their role in shaping a desirable future," he added.

The hall's construction cost $110 million, of which $70 million was federal appropriations for the renovations and $40 million was privately raised, according to the museum press release.

A celebratory ceremony at 10:15 a.m. on the exhibition's opening day is open to the first 300 visitors to the museum's Madison Drive entrance, featuring remarks by Smithsonian Secretary David Skorton and Johnson.

Source: https://edition.cnn.com

How the First Snakes Looked Like?

Monday, May 20, 2019

Artist's rendering of an ancient snake, with tiny hind limbs. Credit: Julius T. Csotonyi

The original snake ancestor was a nocturnal, stealth-hunting predator that had tiny hindlimbs with ankles and toes, according to research published in the open access journal BMC Evolutionary Biology.

The study, led by Yale University, USA, analyzed fossils, genes, and anatomy from 73 snake and lizard species, and suggests that snakes first evolved on land, not in the sea, which contributes to a longstanding debate. They most likely originated in the warm, forested ecosystems of the Southern Hemisphere around 128 million years ago.

Snakes show incredible diversity, with over 3,400 living species found in a wide range of habitats, such as land, water and in trees. But little is known about where and when they evolved, and how their original ancestor looked and behaved.

Lead author Allison Hsiang said: "While snake origins have been debated for a long time, this is the first time these hypotheses have been tested thoroughly using cutting-edge methods. By analyzing the genes, fossils and anatomy of 73 different snake and lizard species, both living and extinct, we've managed to generate the first comprehensive reconstruction of what the ancestral snake was like."

By identifying similarities and differences between species, the team constructed a large family tree and illustrated the major characteristics that have played out throughout snake evolutionary history.

Their results suggest that snakes originated on land, rather than in water, during the middle Early Cretaceous period (around 128.5 million years ago), and most likely came from the ancient supercontinent of Laurasia. This period coincides with the rapid appearance of many species of mammals and birds on Earth.

The ancestral snake likely possessed a pair of tiny hindlimbs, and targeted soft-bodied vertebrate and invertebrate prey that were relatively large in size compared to prey targeted by lizards at the time. While the snake was not limited to eating very small animals, it had not yet developed the ability to manipulate prey much larger than itself by using constriction as a form of attack, as seen in modern Boa constrictors.

While many ancestral reptiles were most active during the daytime (diurnal), the ancestral snake is thought to have been nocturnal. Diurnal habits later returned around 50-45 million years ago with the appearance of Colubroidea -- the family of snakes that now make up over 85% of living snake species. As colder night time temperatures may have limited nocturnal activity, the researchers say that the success of Colubroidea may have been facilitated by the return of these diurnal habits.

The results suggest that the success of snakes in occupying a range of habitats over their evolutionary history is partly due to their skills as 'dispersers'. Snakes are estimated to be able to travel ranges up to 110,000 square kilometres, around 4.5 times larger than lizards. They are also able to inhabit environments that traditionally hinder the dispersal of terrestrial animals, having invaded aquatic habitats multiple times in their evolutionary history.


Story Source:

Materials provided by BioMed CentralNote: Content may be edited for style and length.


Journal Reference:

  1. Allison Y Hsiang, Daniel J Field, Timothy H Webster, Adam DB Behlke, Matthew B Davis, Rachel A Racicot, Jacques A Gauthier. The origin of snakes: revealing the ecology, behavior, and evolutionary history of early snakes using genomics, phenomics, and the fossil recordBMC Evolutionary Biology, 2015; 15 (1) DOI: 10.1186/s12862-015-0358-5

Source: www.sciencedaily.com

How Do Scientists Know What Dinosaurs Looked Like?

Friday, February 1, 2019

Triceratops painting by Charles Knight

Picture this. You’re out in sun-drenched territory in Morrison, Colorado. As you stop to close your eyes and take a deep breath in the searing heat and wipe another steady stream of sweat from your face, you notice a rock that seems a bit different. It’s hard to see it at first, but the color, texture, and placement seem a bit off in its surrounding. You clamber over the terrain separating you from this object of intrigue, keeping your gaze locked on the exact spot you noticed when you first opened your eyes from that deep breath.  Now that you’re at the spot, you believe that your suspicions are correct. This rock seems to be more than just a rock. With your field gear, you begin to excavate carefully around the rock, slowly revealing what can be clearly identified as a fossilized jaw of some prehistoric creature. Excited that your amateur paleontological journey has paid off, you ask yourself while staring wide-eyed at your discovery, “What was this and what in the world did it look like?”

While we all may not be in that position in our lives, if you’re a fan of dinosaurs and other amazing prehistoric creatures, you may have imagined yourself in this situation. You could make the find of the century somewhere! You’re more likely to have this daydream after watching a documentary or Jurassic Park movie where these amazing creatures are brought back to life on the screen.

The question remains: How do those fossils go from that exhilarating moment of discovery to become a classified, named, and fully imagined drawing or computer model of a dinosaur? Between discovery and depiction, there is a lot of scientific sleuthing and artistic licensing that comes into play. Over the course of the past several decades, our understanding of dinosaurs has changed dramatically and so has their depictions. From bipedal, lumbering, tail-draggers to intelligent, complex, and sometimes feathered beasts, a lot has changed in our understanding of dinosaurs. How we depict dinosaurs has also changed to reflect these new understandings.

A depiction of a Tyrannosaurus by Charles Knight. Credit: Public domain/Wikimedia Commons

Illustration of Tyrannosaurus rex. Credit: Wikimedia Commons

While it’s impossible for any scientists or artist to say that their understanding or recreation of a dinosaur is 100% accurate, science gets closer to this goal as new discoveries are made. Let’s take some time to dive in and see how the process brings these creatures back to life, from paleontologist to paleoartist.

Paleontologist

Paleontologists are scientists who study fossils of organisms. The study of these fossils ultimately helps us study the history of life on Earth. Not all paleontologists study dinosaurs. There is a myriad of different fields of expertise in paleontology, like micropaleontology, paleobotany, and invertebrate paleontology. Paleontologists study some of the largest creatures to ever exist on Earth like dinosaurs, all the way to the smallest microscopic plants and animals. This work takes place in a variety of places, from the lab to the field. Paleontologists use a variety of tools, whether they are extracting fossils from the Earth or using computer models to simulate the movement or vocalization of creatures. This work is incredibly important, not only because it tells us about life on Earth in the past, but because it also tells us an incredible amount about the creatures that exist today, how the world as we know it came to be, how Earth’s processes have changed the planet, how the climate has changed over time, and how these processes may impact humanity in the future. Even though not all paleontologists will agree about other things, they’ll all tell you that studying dinosaurs does in fact matter.

Going back to our fossil dream, how do these fossils go from being in the ground to places in our books or movie screens?

The Paleontologist’s Process:

Here is the process paleontologist would follow when a fossil is discovered in the field.

1 - Know your geographic location to know your geologic time location.

Paleontologists want to know the geographic location so that they will be able to determine their geologic time location. North America, and the United States, in particular, is well-mapped in terms of what rock layers are exposed across the country. This information is readily available by the US Geological Survey. Knowing the rock layer and geographic location of your fossil can allow you to narrow down your search in terms of which organisms were alive during that time and how their environment may have looked. 

2 - An eye for clues.

Careful observation of your fossil can lead you to a lot of very useful information. For example, the teeth in a fossilized jawbone can tell you the diet of your organism. This information can lead you to the part of the phylogenetic, or “family tree” where the dinosaur belonged. Phylogenetic trees are a way of visualizing evolutionary relationships between a group of organisms that share a common ancestor. A phylogenetic tree branches out as new species or groups of species are formed with their own unique traits. This can be incredibly helpful as members of similar branches of the tree will have similar traits. The phylogenetic tree on page 7 of your Dinosaur ID Guide shows which dinosaurs were alive and during what time. The names and numbers on the left side of the sheet indicate what era and how many million years ago they lived. You’ll notice that not all of the dinosaurs you’ve heard of are on the diagram. Some you’ve heard of before were alive during the entire age of dinosaurs. For example, Ceratopsia, the group where the Triceratops belonged, appeared first in the late Triassic at the earliest.

3 - Environment.

Based on the location of the fossil and the relative age of the rock, you can learn about that location’s environment during the time that dinosaur was alive. The world has changed in an incredible amount of ways over time. Using Howard Hughes Medical Institute’s Earth Viewer, move back in time to see a location and details about that location back when your dinosaur was alive. For example, the location of Los Angeles during this time period is no longer coastal area, but in a mountainous area. That type of environment could therefore be a potentially colder and rockier environment than exists there now. 

4 - Look deeper.

When there is very little fossil evidence, paleontologists take a much deeper look. Microscopic details in the structures of the bones can lead them in the right direction to identifying their dinosaurs. Minute details can mean big things to paleontologists, whether it be places for feathers to connect or channels for air sacs. Paleontologists also know the value of collaboration and what it means to support each as they make new discoveries.

 

Paleoartist

Paleoart is the artistic representation of prehistoric creatures that lived long ago. In the realm of paleoart, artists, in many cases, work to blend and compare the anatomy of existing animals, examples of creatures that are more well known, and anatomical structure from fossils that are as realistic as possible based on the information that’s available at the time. One such artist, Gabriel Ugueto, has taken his passion for the natural world and art and translated it into a career recreating dinosaurs and other extinct species for the public to see.

Gabriel has taken his passion as a herpetologist, someone who studies amphibians and reptiles, into the artistic realm. Using his knowledge, he’s developed his own method to recreate the fantastic organisms from long ago. Gabriel first looks at the bone structure to determine the shape of the organism. From there, Gabriel works outward to create the skin, scales, feathers, and color based on the time period and where the animal lived. Using all this information in concert, Gabriel creates his own interpretation of how the organism may have looked.

Source: www.sciencefriday.com

First Teaser Trailer for Animated 'Jurassic World: Camp Cretaceous' Series on Netflix

Friday, June 7, 2019

Netflix has ordered the animated series “Jurassic World: Camp Cretaceous,” inspired by the multi-billion dollar “Jurassic Park” film franchise.

The series is set within the timeline of the 2015 film “Jurassic World” and hails from DreamWorks Animation. It follows a group of six teenagers chosen for a once-in-a-lifetime experience at a new adventure camp on the opposite side of Isla Nublar. But when dinosaurs wreak havoc across the island, the campers are stranded. Unable to reach the outside world, they’ll need to go from strangers to friends to family if they’re going to survive.

Scott Kreamer and Lane Lueras will serve as showrunners and executive producers. Steven Spielberg, Frank Marshall, and Colin Trevorrow will executive produce. Zack Stentz serves as consulting producer. The series is expected to launch on Netflix in 2020.

Produced by Universal Pictures and Amblin Entertainment, the first two “Jurassic World” films have grossed have grossed nearly $3 billion. The third installment debuts in theaters on June 11, 2021. Those films were preceded by the blockbusters “Jurassic Park,” “The Lost World: Jurassic Park,” and “Jurassic Park III.”

“Camp Cretaceous” is the latest in a long line of DreamWorks Animation projects to debut on Netflix. DreamWorks Animation and Netflix signed an expansive first look deal for animated series based on Universal Pictures properties, as well as original and acquired IP, following the acqusition of DreamWorks by NBCUniversal. Among the shows the studio has debuted on Netflix are “She-Ra and the Princesses of Power,” the “Tales of Arcadia” trilogy, and “The Boss Baby: Back in Business.” Upcoming projects include an animated “Fast & Furious” series.

Source: https://variety.com

What Came First, The Feather or The Bird? Prehistoric Mystery SOLVED

Wednesday, June 5, 2019

Dinosaur discovery: Feathers predate birds by many millions of years (Image: GETTY)

DINOSAURS were covered in feathers at least 100 million years before the first birds took flight, archaeologists at Bristol University has spectacularly announced.

The genealogy of feathered dinosaurs promises to forever shakeup how paleontologists approach dinosaurs, birds and flying reptiles or pterosaurs. A study led by the University of Bristol, UK, has found the evolution of feathers significantly predates the evolution of birds. The first major clue came earlier this year when archaeologists discovered feathers on pterosaurs – winged monsters from the late Triassic and Cretaceous period. Pterosaurs like the Pterodactyl, are some of the earliest known vertebrates to have developed the power of flight.

But if these fascinating creatures were covered in feathers, researchers assume feathers made an appearance in the evolutionary timeline even earlier.

The oldest known ancestor of the modern bird is the small dinosaur Archaeopteryx.

These winged and fanged beasts lived approximately 150 million years ago, in the late Jurassic.

Professor Mike Benton, from the University of Bristol’s School of Earth Sciences, said: “The oldest bird is still Archaeopteryx first found in the Late Jurassic of southern Germany in 1861, although some species from China are a little older.

“Those fossils all show a diversity of feathers – down feathers over the body and long, vaned feathers on the wings.

“But, since 1994, palaeontologists have been contending with the perturbing discovery, based on hundreds of amazing specimens from China, that many dinosaurs also had feathers.”

Another clue came when scientists had the opportunity to work on the fossilised remains of Kulindadromeus – a dinosaur only discovered in the last 10 years.

The small bipedal creature is believed to have been covered in a type of proto-feathers or feather-like fuzz.

Dinosaur feathers: Feathers likely developed as insulation against changing climate (Image: Yuan Zhang

According to Dr Maria McNamara, the study’s co-author from the University College Cork, the dinosaur specimen had an incredibly well-preserved skin.

The skin showed signs of scales on the legs and tails and “strange whiskery feathers” all over the rest of the body.

Dr McNamara said: “What supposed people was that this dinosaur was as far from birds in the evolutionary tree as could be imagined. Perhaps feathers were present in the very first dinosaurs.”

The findings suggest, according to Baoyu Jiang from the University of Nanjing, the origin of feathers could be pushed back as far as 200 million years into the past.

The researcher, who co-authored the dinosaur study, said: “At first, the dinosaurs with feathers were close to the origin of birds in the evolutionary tree.

Dinosaurs, pterosaurs and their ancestors had feathers too.

Professor Mike Benton, University of Bristol

“This was not so hard to believe. So, the origin of feathers was pushed back at least to the origin of those bird-like dinosaurs, maybe 200 million years ago.”

Even modern-day chickens have an interesting link to the terrifying monsters of the past.

The harmless birds have scales on their necks and legs, which through the process of reversal started off as feathers.

In 2015, scientists reverse-engineered developing chicken embryos to alter their bone structure.

By inhibiting certain genes in the development process, the baby chicks developed snouts resembling Velociraptor bone structures, rather than bird beaks.

All of these findings combined give credibility to the idea feathers evolved long before birds, as a form of insulation and not a flight-aid.

Professor Benton said: “So, the dinosaurs, pterosaurs and their ancestors had feathers too.

“Feathers then probably arose to aid this speeding up of physiology and ecology, purely for insulation.

“The other functions of feathers, for display and of course for flight, came much later.”

Overall, this pushes the development of feathers back by some 250 million years “at least”.

The study was published in the journal Trends in Ecology & Evolution.

Source: www.express.co.uk

Fostoria dhimbangunmal: 'Spectacular' Opal-Laced Fossils Reveal Previously Unknown Australian Dinosaur

Tuesday, June 4, 2019

Artist’s impression of Fostoria dhimbangunmal. Illustration: James Kuether

Paleontologists in Australia have identified a previously unknown plant-eating dinosaur from the mid-Cretaceous. Remarkably, the fossilized bones of these creatures, which glisten in hues of blue and green, are preserved in opal.

New research published in the Journal of Vertebrate Paleontology describes Fostoria dhimbangunmal, a dinosaur species that’s closely related to Iguanodon and Muttaburrasaurus. Fossils of four specimens were found in Lightning Ridge, a small town in the Australian Outback. As reported in The Australian, paleontologists recovered the opal-encrusted fossils in 1984 after being alerted to their presence by an opal miner, Robert Foster, who was working 10 meters (33 feet) below a field known as the “Sheepyard.”

After the excavation, these fossils went on display at the Australian Museum in Sydney, where they remained for decades. The Foster family recently donated the fossils to the Australian Opal Centre, where researchers recognized the opalized items as deserving of further investigation. The analysis, led by Phil Bell from the University of New England in Armidale, Australia, revealed the fossils belonged to a new species. The researchers named the dinosaur in honor of Foster and the field above the deposit where the bones were found; the name dhimbangunmal (pronounced dim-baan goon-mal) translates to sheep yard in Yawaalaraay, the local indigenous language.

Lightning Ridge is famous for its opal gemstones, which form underground over long timescales from a solution of silicon dioxide and water (more about the process here). It’s not uncommon to find the odd bone or tooth that has undergone opalization, but the discovery of around 60 opal-encrusted bones (including the braincase) from a single individual—an adult Fostoria—is without precedent.

The opalized fossils of another three individuals, all juveniles, were also identified in the new study. The remains were all found jumbled together in the opal mine, leading Bell to speculate that the individuals were once part of a herd or a family, as reported in National Geographic. The researchers used a CT scanner to analyze the fossils without having to damage them.

Opalized toe fossil of Fostoria dhimbangunmal. Image: Australian Opal Centre

Fostoria is now the earliest known iguanodontian dinosaur ever found in Australia. Dating back to the mid-Cretaceous some 100 million years ago, these flat-toothed, herbivorous creatures foraged as they stood on their hind limbs. Today, this region of New South Wales is barren and dusty, but during the mid-Cretaceous it contained rivers, lagoons, and vast tracts of vegetation. Importantly, Fostoria was “an early member of a group that would elsewhere evolve into the duckbilled hadrosaurs, which were common in North America and Asia toward the end of the time of the dinosaurs,” James Kuether wrote for National Geographic.

“It’s exciting enough to have a bonebed of new dinosaurs from Australia,” Liz Freedman Fowler, an assistant professor of biology at Dickinson State University, said in an email to Gizmodo. “To also have them preserved in beautiful opal is a spectacular bonus. Kudos to the original discoverers for recognizing the importance of their find so the bones could be excavated safely and scientifically,” said Fowler, who wasn’t involved with the new research.

Australia has a long history of producing “bizarre and amazing creatures,” according to paleontologist Terry Gates from the Department of Biological Sciences at North Carolina State University, also not involved with the new study. Gates attributed this to the continent’s isolated geographic position. The Fostoria discovery “fills in a glaring gap in our understanding of duck-billed dinosaur evolution in a spectacular way,” explained Gates in an email to Gizmodo.

To which he added: “It’s hard to imagine a more perfect shape for gemstones than a new species of dinosaur.”

Source: https://gizmodo.com

How Deinonychus Changed Our Understanding of Dinosaurs

Tuesday, June 4, 2019

Deinonychus antirrhopus by tuomaskoivurinne

Academics used to tease paleontologists, saying that while dinosaurs appeal to children, they won’t answer the important evolutionary questions.

Yale’s John Ostrom (1928-2005) proved them wrong.

Fifty years ago, in Feb. 1969, Ostrom, then an assistant professor of geology and geophysics at Yale, published a paper describing a previously unknown dinosaur he dubbed Deinonychus, meaning “terrible claw” in Greek. The paper reignited public interest in dinosaurs and upended common assumptions in the field. It also helped answer the question: Where do birds come from?

As an undergraduate student at Union College Ostrom was captivated by the works of George Gaylord Simpson, a paleontologist-turned-evolutionary biologist. Ostrom decided against entering medicine as his father had hoped, and instead pursued a Ph.D. at Columbia University to study with Simpson. In 1961, Ostrom joined Yale’s Department of Geology and Geophysics, and he remained there until his retirement in 1993, though he remained active in research and writing as an emeritus professor at Yale until 2001.

The name Deinonychus may not be familiar to non-scientists, but millions of people have seen one on the big screen. In the 1993 film “Jurassic Park” the murderous Velociraptors were, in fact, based on Deinonychus. (Real velociraptors were considerably smaller than the creatures in the film, about the same size as a turkey.)

Michael Crichton, the writer of the “Jurassic Park” novel on which the movie was based had been swept up in the “Dinosaur Renaissance” sparked by Ostrom’s discovery and the work of one of his students, Robert Bakker ’67, and the paleoartist Greg Paul in the 1970s and 1980s.

The quarry where Yale paleontologist John Ostram discovered Deinonychus.

“I was in my office when the telephone rang one morning. ‘Professor Ostrom, this is Michael Crichton,’” the Yale professor recalled in 1997 while speaking to The New York Times. “And we had a very interesting conversation.”

While Crichton used the physical attributes and hypothesized behaviors described to him by Ostrom to describe the creatures in his novel, he opted for the more dramatic name “velociraptor.” “Jurassic Park” went on to become a pop culture juggernaut, inspiring a whole new generation to be captivated by dinosaurs and eager to study them.

Ostrom’s work didn’t just change how dinosaurs were perceived by the public, he also shifted the conventional wisdom in academia. According to Ostrom’s last graduate student and current Peabody Museum paleontologist, Daniel Brinkman ’94 M.Phil., “prior to Ostrom, dinosaurs were thought of as large, lumbering, cold-blooded, and slow-witted evolutionary failures.”

“The discovery of Deinonychus not only reshaped our understanding of dinosaurs, it recalibrated how we understand evolution. Darwin’s notion of steady, gradual change had led scientists to believe that dinosaurs must have been quite primitive in their behavior and cognitive ability. Deinonychus called this presumption into serious question. Half a century later, the way we conceive of prehistoric life is completely transformed,” explains David Skelly, director of the Yale Peabody Museum and the Frank R. Oastler Professor of Ecology.

Ostrom deduced that Deinonychus had an upright posture by analyzing the shape and function of its limbs. As Ostrom was studying Deinonychus, he came across the work of J.E Heath, who had proposed that an upright posture benefits warm-blooded animals because it allows the muscles to retain and generate heat.

The two observations led Ostrom to suggest that dinosaurs could have been warm-blooded. The paleontological community rallied to investigate the question.

A drawing of Deinonychus by Robert Bakker ’67, which appeared in Ostram’s original paper describing the dinosaur.

Bakker, who had been a student of Ostrom and went on to be a renowned paleontologist in his own right, became one of the biggest proponents of this hypothesis and led the scientific debate for decades. Today, most scientists accept that dinosaurs were more metabolically active than present day reptiles, but caution against a simplistic view of warm or cold bloodedness.

Discovering Deinonychus also ressurrected the hypothesis that birds descended from dinosaurs. Back in the 1860s renowned biologist Thomas Henry Huxley had championed this idea. While describing the anatomy of fossilized bird remains he once remarked: “[If] found in the fossil state, I know not by what test they could be distinguished from the bones of a Dinosaurian.”

The similarities between the remains of both birds and dinosaurs also struck Ostrom in 1970 while he was visiting the Teylers Museum in the Netherlands.

As he was inspecting what was believed to be a pterodactyl, he had a startling realization. Through his intimate knowledge of Deinonychus and his keen eye, Ostrum recognized that the specimen was in fact a feathered bird. At that time he hypothesized that the specimen was of Archaeopteryx, a prehistoric bird. The incident sparked Ostrom’s curiosity and his focus shifted to the question of the evolutionary ancestry of birds.

Over the next decade, Ostrom published a series of papers that investigated the possible relationship between Deinonychus and Archaeopteryx. Out of that, he postulated that birds were direct descendants of the dinosaurs, rather than simply sharing a common ancestry. Further, he claimed that flight evolved when feathered dinosaurs flapped their arms in pursuit of prey. The scientific community was rocked by these hypotheses and a vigorous debate occurred in the succeeding decades.

Today almost all scientists accept Ostrom’s findings.

By persevering in the face of difficult questions, Ostrom upended multiple core assumptions in paleontology, sparked a Jurassic renaissance, and inspired multiple generations to look at dinosaurs with wonder.

In one of Ostrom’s final papers, “How Bird Flight Might Have Come About,” he gives a “last word,” saying, “The missing, unknowable fossil record can never be allowed to stifle our curiosity.”

It certainly didn’t stifle his.

Source: https://scitechdaily.com

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