Tyrannosaurus rex, correct name?

This 25 March 2018 video says about itself:

Why T.rex Shouldn’t Have Been Called T.rex

The name Tyrannosaurus rex is absolutely iconic, evoking images of a powerful, ancient predator, the king of the tyrant lizards. But, if you go back and examine the earliest discoveries of this legendary animal, it turns out that this shouldn’t technically have been its name at all.


Dinosaurs, why horns?

This 2015 video from Canada is called The Royal Ontario Museum’s Ceratopsians.

From Queen Mary University of London in England:

Dinosaur frills and horns did not evolve for species recognition

March 21, 2018

The elaborate frills and horns of a group of dinosaurs including Triceratops and Styracosaurus did not evolve to help species recognise each other, according to researchers at Queen Mary University of London.

It has been suggested that different species that live in the same location may evolve features in order to distinguish one another to help avoid problems such as hybridisation, where two individuals of different species produce infertile or unfit offspring.

To test this hypothesis the researchers examined patterns of diversity in the ornamentation of 46 species of ceratopsians, the horned dinosaurs, but found no difference between species that lived together and those that lived separately.

A previous research paper from Queen Mary found that the frill in one ceratopsian species, Protoceratops, may have evolved under sexual selection. These new findings appear to add evidence to this across the entire group.

The researchers also found evidence that ornamental traits seemed to evolve at a much faster rate than other traits. As these structures are costly to grow and maintain, this finding similarly points to a strong selective pressure on these traits.

The study was published in Proceedings of the Royal Society B.

Andrew Knapp, PhD candidate from the School of Biological and Chemical Sciences and lead author of the study, said: “This resolves a long-standing and hitherto untested hypothesis concerning the origin and function of ornamental traits in ceratopsian dinosaurs. Many general discussions of ceratopsian ornaments in museum signage and popular literature often include examples of what they might have been for, but these tend to be rather speculative.

“We have shown that species recognition, one of the commonest explanations, is unlikely to be responsible for the diversity or origin of ornamentation in this group.”

The researchers believe the implications extend beyond the scope of ceratopsians and have consequences for the study of evolutionary theory over vast stretches of time.

The fossil record offers an opportunity to see evolution in action over much longer time periods than can be achieved with living organisms, but it is difficult to assign explanations to unusual features such as ceratopsian ornaments with the limited information that fossils provide.

The researchers have now largely ruled out one explanation, species recognition, and provided some evidence for another, sexual selection.

Mr Knapp said: “If sexual selection is indeed the driver of ornament evolution in ceratopsians, as we are increasingly confident it is, demonstrating it through different lines of evidence can provide a crucial window into tracing its effects over potentially huge timescales.”

He added: “Modern computer models have suggested that sexual selection can promote rapid speciation, adaptation, and extinction. In our world of increasing pressure on the natural world, these predictions may have important consequences for conservation and the fate of living things everywhere.”

To test these predictions the researchers hope to look at changes in the fossil record and gather further evidence to first identify sexual selection in a fossil group.

The study was conducted in collaboration with the Raymond M. Alf Museum of Paleontology in California and Natural History Museum of Utah. It was funded by a Natural Environment Research Council (NERC) doctoral training partnerships (DTP) grant through the London DTP programme.

Vote NO against Dutch Big Brother law, 21 March

This 13 March 2018 Dutch video is by the Party for the Animals in the Netherlands. It is about a girl Fleur, who has a pet Tyrannosaurus rex. Supposedly, that carnivorous dinosaur is for ‘security’. However, the tyrannosaur ends up eating Fleur.

On 21 March 2018, there will be elections for most local authorities in the Netherlands. On that day, people can also vote in a referendum, for or against the government’s new ‘Big Brother’ law which supposedly is for ‘security’. It gives the secret police new powers to spy on everyone and to share the results of that spying with foreign services like Trump‘s CIA, the secret police of Erdogan, NATO ally and warmongering dictator of Turkey, the secret police of Saudi Arabia (that warmongering dictatorship is an ally though not a NATO member), etc.

The Party for the Animals opposes that new law. That is what their ‘tyrannosaur‘ video is about. And they are not the only ones.

In this 8 March 2018 video, Amnesty International explains why the new Big Brother law (‘sleepwet‘ in Dutch) threatens human rights.

In this 8 March 2018 video, the Dutch Socialist Party explains why voters should oppose that law. They explain that in English, here, as well.

Here is an open letter by scores of Dutch cybersecurity experts; warning that the law threatens privacy, making it easier for hackers to steal people’s Internet data.

Mammal-like reptiles coexisted with dinosaurs, discovery

This 13 March 2018 video says about itself:

Mystery of the Phantom Fossil Footprints

A new study has re-discovered fossil collections from a 19th century hermit that validate ‘phantom’ fossil footprints collected in the 1950s showing dicynodonts coexisting with dinosaurs.

“The first skeletal evidence of a dicynodont from the lower Elliot Formation of South Africa” by Christian F. Kammerer, North Carolina Museum of Natural Sciences. Published: 3-14-2018, in Palaeontologia Africana.

Video by Adrian Smith

Narrated by Eban Crawford

Illustrations by Matt Celeskey & Dmitry Bogdanov

From the North Carolina Museum of Natural Sciences in the USA:

60-year-old paleontological mystery of a ‘phantom’ dicynodont

March 14, 2018

A new study has re-discovered fossil collections from a 19th century hermit that validate ‘phantom’ fossil footprints collected in the 1950s showing dicynodonts coexisting with dinosaurs.

Before the dinosaurs, around 260 million years ago, a group of early mammal relatives called dicynodonts were the most abundant vertebrate land animals. These bizarre plant-eaters with tusks and turtle-like beaks were thought to have gone extinct by the Late Triassic Period, 210 million years ago, when dinosaurs first started to proliferate. However, in the 1950s, suspiciously dicynodont-like footprints were found alongside dinosaur prints in southern Africa, suggesting the presence of a late-surviving phantom dicynodont unknown in the skeletal record. These “phantom” prints were so out-of-place that they were disregarded as evidence for dicynodont survival by paleontologists. A new study has re-discovered fossil collections from a 19th century hermit that validate these “phantom” prints and show that dicynodonts coexisted with early plant-eating dinosaurs. While this research enhances our knowledge of ancient ecosystems, it also emphasizes the often-overlooked importance of trace fossils, like footprints, and the work of amateur scientists.

“Although we tend to think of paleontological discoveries coming from new field work, many of our most important conclusions come from specimens already in museums“, says Dr. Christian Kammerer, Research Curator of Paleontology at the North Carolina Museum of Natural Sciences and author of the new study.

The re-discovered fossils that solved this mystery were originally collected in South Africa in the 1870s by Alfred “Gogga” Brown. Brown was an amateur paleontologist and hermit who spent years trying, with little success, to interest European researchers in his discoveries. Brown had shipped these specimens to the Natural History Museum in Vienna in 1876, where they were deposited in the museum’s collection but never described.

“I knew the Brown collections in Vienna were largely unstudied, but there was general agreement that his Late Triassic collections were made up only of dinosaur fossils. To my great surprise, I immediately noticed clear dicynodont jaw and arm bones among these supposed ‘dinosaur’ fossils”, says Kammerer. “As I went through this collection I found more and more bones matching a dicynodont instead of a dinosaur, representing parts of the skull, limbs, and spinal column.” This was exciting — despite over a century of extensive collection, no skeletal evidence of a dicynodont had ever been recognized in the Late Triassic of South Africa.

Before this point, the only evidence of dicynodonts in the southern African Late Triassic was from questionable footprints: a short-toed, five-fingered track named Pentasauropus incredibilis (meaning the “incredible five-toed lizard foot”). In recognition of the importance of these tracks for suggesting the existence of Late Triassic dicynodonts and the contributions of “Gogga” Brown in collecting the actual fossil bones, the re-discovered and newly described dicynodont has been named Pentasaurus goggai (“Gogga’s five-[toed] lizard”).

“The case of Pentasaurus illustrates the importance of various underappreciated sources of data in understanding prehistory,” says Kammerer. “You have the contributions of amateur researchers like ‘Gogga’ Brown, who was largely ignored in his 19th century heyday, the evidence from footprints, which some paleontologists disbelieved because they conflicted with the skeletal evidence, and of course the importance of well-curated museum collections that provide scientists today an opportunity to study specimens collected 140 years ago.”

Cynodont fossils from Brazil shed light on mammal evolution: here.

Archaeopteryx could fly indeed

This 2014 video says about itself:

Scanning the Teyler Archaeopteryx fossil at the ESRF Grenoble

2 November 2014

In order to study the Teyler Archaeopteryx fossil, it is being scanned in Grenoble using synchrotron X-ray microtomography. The end of the video shows the specimen fully wrapped and mounted on the object table in front of the beam that is coming out the square hole in the blue box.

From the European Synchrotron Radiation Facility:

The early bird got to fly: Archaeopteryx was an active flyer

March 13, 2018

The question of whether the Late Jurassic dino-bird Archaeopteryx was an elaborately feathered ground dweller, a glider, or an active flyer has fascinated palaeontologists for decades. Valuable new information obtained with state-of-the-art synchrotron microtomography at the ESRF, the European Synchrotron (Grenoble, France), allowed an international team of scientists to answer this question in Nature Communications. The wing bones of Archaeopteryx were shaped for incidental active flight, but not for the advanced style of flying mastered by today’s birds.

Was Archaeopteryx capable of flying, and if so, how? Although it is common knowledge that modern-day birds descended from extinct dinosaurs, many questions on their early evolution and the development of avian flight remain unanswered. Traditional research methods have thus far been unable to answer the question whether Archaeopteryx flew or not. Using synchrotron microtomography at the ESRF’s beamline ID19 to probe inside Archaeopteryx fossils, an international team of scientists from the ESRF, Palacký University, Czech Republic, CNRS and Sorbonne University, France, Uppsala University, Sweden, and Bürgermeister-Müller-Museum Solnhofen, Germany, shed new light on this earliest of birds.

Reconstructing extinct behaviour poses substantial challenges for palaeontologists, especially when it comes to enigmatic animals such as the famous Archaeopteryx from the Late Jurassic sediments of southeastern Germany that is considered the oldest potentially free-flying dinosaur. This well-preserved fossil taxon shows a mosaic anatomy that illustrates the close family relations between extinct raptorial dinosaurs and living dinosaurs: the birds. Most modern bird skeletons are highly specialised for powered flight, yet many of their characteristic adaptations in particularly the shoulder are absent in the Bavarian fossils of Archaeopteryx. Although its feathered wings resemble those of modern birds flying overhead every day, the primitive shoulder structure is incompatible with the modern avian wing beat cycle.

“The cross-sectional architecture of limb bones is strongly influenced by evolutionary adaptation towards optimal strength at minimal mass, and functional adaptation to the forces experienced during life”, explains Prof. Jorge Cubo of the Sorbonne University in Paris. “By statistically comparing the bones of living animals that engage in observable habits with those of cryptic fossils, it is possible to bring new information into an old discussion”, says senior author Dr. Sophie Sanchez from Uppsala University, Sweden

Archaeopteryx skeletons are preserved in and on limestone slabs that reveal only part of their morphology. Since these fossils are among the most valuable in the world, invasive probing to reveal obscured or internal structures is therefore highly discouraged. “Fortunately, today it is no longer necessary to damage precious fossils”, states Dr. Paul Tafforeau, beamline scientist at the ESRF. “The exceptional sensitivity of X-ray imaging techniques for investigating large specimens that is available at the ESRF offers harmless microscopic insight into fossil bones and allows virtual 3D reconstructions of extraordinary quality. Exciting upgrades are underway, including a substantial improvement of the properties of our synchrotron source and a brand new beamline designated for tomography. These developments promise to give even better results on much larger specimens in the future.”

Scanning data unexpectedly revealed that the wing bones of Archaeopteryx, contrary to its shoulder girdle, shared important adaptations with those of modern flying birds. “We focused on the middle part of the arm bones because we knew those sections contain clear flight-related signals in birds”, says Dr. Emmanuel de Margerie, CNRS, France. “We immediately noticed that the bone walls of Archaeopteryx were much thinner than those of earthbound dinosaurs but looked a lot like conventional bird bones”, continues lead author Dennis Voeten of the ESRF. “Data analysis furthermore demonstrated that the bones of Archaeopteryx plot closest to those of birds like pheasants that occasionally use active flight to cross barriers or dodge predators, but not to those of gliding and soaring forms such as many birds of prey and some seabirds that are optimised for enduring flight.”

“We know that the region around Solnhofen in southeastern Germany was a tropical archipelago, and such an environment appears highly suitable for island hopping or escape flight”, remarks Dr. Martin Röper, Archaeopteryx curator and co-author of the report. “Archaeopteryx shared the Jurassic skies with primitive pterosaurs that would ultimately evolve into the gigantic pterosaurs of the Cretaceous. We found similar differences in wing bone geometry between primitive and advanced pterosaurs as those between actively flying and soaring birds”, adds Vincent Beyrand of the ESRF.

Since Archaeopteryx represents the oldest known flying member of the avialan lineage that also includes modern birds, these findings not only illustrate aspects of the lifestyle of Archaeopteryx but also provide insight into the early evolution of dinosaurian flight. “Indeed, we now know that Archaeopteryx was already actively flying around 150 million years ago, which implies that active dinosaurian flight had evolved even earlier!” says Prof. Stanislav Bureš of Palacký University in Olomouc. “However, because Archaeopteryx lacked the pectoral adaptations to fly like modern birds, the way it achieved powered flight must also have been different. We will need to return to the fossils to answer the question on exactly how this Bavarian icon of evolution used its wings”, concludes Voeten.

It is now clear that Archaeopteryx is a representative of the first wave of dinosaurian flight strategies that eventually went extinct, leaving only the modern avian flight stroke directly observable today.

Ankylosaur dinosaur fossils, new theory

This 2016 video is called Interesting Facts About Ankylosaurus.

From the Canadian Museum of Nature:

Flipside of a dinosaur mystery: ‘Bloat-and-float’ explains belly-up ankylosaur fossils

February 28, 2018

Summary: Why are fossil remains of ankylosaurs — armored ‘tanks of the Cretaceaous’ — usually found belly-up? A paleontologist proposes the explanation is ‘bloat-and-float’, where the dead dinos would float downstream, bloat, flip upside down, and be fossilized that way.

A scientist with the Canadian Museum of Nature has answered a long-standing mystery about why fossils of ankylosaurs — the “armoured tanks” of the dinosaur world — are mainly found belly-side up. In doing so, he has ruled out three other competing theories involving clumsiness, predation, and the effects of bloating as seen in armadillo roadkills.

Palaeontologist Dr. Jordan Mallon says the evidence points to a phenomenon called “bloat-and-float,” whereby the bloating carcasses of ankylosaurs would end up in a river, flip belly-side up due to the weight of their heavy armour, and then float downstream. The remains would wash ashore, where decomposition and then fossilization would seal the dinosaur remains in their upside-down death pose.

“Textbooks have touted that ankylosaur fossils are usually found upside down, but no one has gone back and checked the records to make sure that’s the case,” explains Mallon. The observations date from the 1930s. Indeed, the fossils of two star ankylosaurs described in 2017, Borealopelta from Alberta and Zuul from Montana, were found upside down.

Mallon examined 32 ankylosaur fossils from Alberta (of which 26 were found belly up), photos of specimens, field notes, and other signs such as erosion of the exposed surface, sun bleaching, and the presence of lichens.

The results are published in the online journal Palaeogeography, Palaeoclimatology, Palaeoecology. Collaborators included armadillo experts Drs. Colleen McDonough and Jim Loughry of Valdosta State University in Georgia, and Dr. Don Henderson, with Drumheller Alberta’s Royal Tyrrell Museum of Palaeontology.

Mallon ruled out three other theories before settling on “bloat-and-float” to explain the preponderance of the belly-up remains.

“One idea was that ankylosaurs were simply clumsy, tripping over themselves or rolling down hills and ending up dying that way,” he says. But since ankylosaurs existed for about 100 million years, clumsy habits would not fit with their apparent evolutionary success.

Another theory was that ankylosaurs were prey for carnivores, such as hungry tyrannosaurids, which would flip the armoured dinosaurs onto their backs to get at the soft underbelly. “If this was true, we would expect to see signs of bite marks, especially on upside-down ones, but we saw marks on only one specimen”, explains Mallon. “Since they were armoured, it makes sense that ankylosaurs were not regularly preyed upon, and the fossil evidence in museum collections supports this.”

The third idea, proposed in the 1980s, is an analogy to what happens with some armadillo roadkills — as the carcass rots and bloats, gas accumulates, and the limbs would splay out, eventually rolling the animal onto its back.

The challenge was to test this hypothesis. Enter McDonough and Loughry who are experts on modern armadillos, which also have an armoured shell. Over the summer of 2016, they studied 174 examples of dead armadillo. “Sure enough, the data show that they do not occur more often on their backs,” says Mallon. The pair even examined dead armadillos placed in plexiglass cases in their backyard to keep away scavengers. Regardless of the positioning of the carcasses, bloating did not cause them to roll over onto their backs.

That left the “bloat-and-float” hypothesis as the most likely explanation for the presence of upside-down fossils. To study this, Mallon turned to computer simulations developed by Dr. Don Henderson, who specializes in the floating behaviour of animals in water.

Ankylosaur fossils in North America are found in river channel deposits, and in the Late Cretaceous Period these animals would have been living along a coastline of what is known as the Western Interior Seaway.

“We designed these models of ankylosaurs, both clubless and clubbed, and looked at their floating behavior,” explains Mallon. The computer modelling showed that the animals would tend to flip upside down quite easily in water. Nodosaurids, which are ankylosaurs with no tail clubs, would flip most easily at the slightest tilt; the ankyosaurids (with clubbed tails), were more stable but could still be flipped.

“So ‘bloat-and-float'” fits with their known environment, and this research helps inform about the transport behavior of dead dinosaurs, which is important to know when studying fossil ecosystems. Ultimately, this is a classic case study of the scientific method: examining alternative hypotheses, finding ways to test them, and ruling them out one-by-one. What you are left with at the end is the most likely explanation.”

All known ankylosaurs, like Edmontonia and Euoplocephalus, were all large, heavily armored, and solely plant eaters. At least that was the case before the discovery of new specimens of Liaoningosaurus. When the armored dinosaur Liaoningosaurus paradoxus was first described in 2001, it didn’t make much of a splash in the popular or paleontological press. The original specimen represented a very small animal, only about 34 cm in total length: here.

What makes dinosaurs dinosaurs?

This 2016 video says about itself:

Dinosaurs are a diverse group of animals of the clade Dinosauria.

They first appeared during the Triassic period, 231.4 million years ago, and were the dominant terrestrial vertebrates for 135 million years, from the start of the Jurassic (about 200 million years ago) until the end of the Cretaceous (66 million years ago), when the Cretaceous–Paleogene extinction event led to the extinction of most dinosaur groups at the end of the Mesozoic Era.

The fossil record indicates that birds are modern feathered dinosaurs, having evolved from theropod ancestors during the Jurassic Period. Birds were the only dinosaurs to survive the extinction event that occurred 66 million years ago.

By Carolyn Gramling, 4:00pm, February 21, 2018:

New fossils are redefining what makes a dinosaur

Defining what’s unique about these ‘fearfully great lizards’ gets harder with new finds

“There’s a very faint dimple here,” Sterling Nesbitt says, holding up a palm-sized fossil to the light. The fossil, a pelvic bone, belonged to a creature called Teleocrater rhadinus. The slender, 2-meter-long reptile ran on all fours and lived 245 million years ago, about 10 million to 15 million years before scientists think dinosaurs first appeared.

Nesbitt, a paleontologist at Virginia Tech in Blacksburg, tilts the bone toward the overhead light, illuminating a small depression in the fossil. The dent, about the size of a thumbprint, marks the place where the leg bone fit into the pelvis. In a true dinosaur, there would be a complete hole there in the hip socket, not just a depression. The dimple is like a waving red flag: Nope, not a dinosaur.

The hole in the hip socket probably helped dinosaurs position their legs underneath their bodies, rather than splayed to the sides like a crocodile’s legs. Until recently, that hole was among a handful of telltale features paleontologists used to identify whether they had their hands on an actual dinosaur specimen.

Another no-fail sign was a particular depression at the top of the skull. Until Teleocrater mucked things up. The creature predated the dinosaurs, yet it had the dinosaur skull depression.

The once-lengthy list of “definitely a dinosaur” features had already been dwindling over the past few decades thanks to new discoveries of close dino relatives such as Teleocrater. With an April 2017 report of Teleocrater’s skull depression (SN Online: 4/17/17), yet another feature was knocked off the list.

Today, just one feature is unique to Dinosauria, the great and diverse group of animals that inhabited Earth for about 165 million years, until some combination of cataclysmic asteroid and volcanic eruptions wiped out all dinosaurs except the birds.

“I often get asked ‘what defines a dinosaur’, ” says Randall Irmis, a paleontologist at the Natural History Museum of Utah in Salt Lake City. Ten to 15 years ago, scientists would list perhaps half a dozen features, he says. “The only one to still talk about is having a complete hole in the hip socket.”

The abundance of recent discoveries of dinosauromorphs, a group that includes the dinosaur-like creatures that lived right before and alongside early dinosaurs, does more than call diagnostic features into question. It is shaking up long-standing ideas about the dinosaur family tree.

To Nesbitt, all this upheaval has placed an even more sacred cow on the chopping block: the uniqueness of the dinosaur.

“What is a dinosaur?” Nesbitt says. “It’s essentially arbitrary.”