Utah dinosaur tracks site open to the public


This video from the USA is called Dinosaur Footprints Set For Public Display In Utah.

From Associated Press:

Site of dinosaur tracks to be unveiled

by Brady Mccombs

SALT LAKE CITY, UTAH – A dry wash full of 112-million-year-old dinosaur tracks that include an ankylosaurus, dromaeosaurus and a menacing ancestor of the Tyrannosaurus rex, is set to open to the public this fall in Utah.

There are more than 200 tracks near the city of Moab from 10 different ancient animals that lived during the early Cretaceous period, said Utah Bureau of Land Management paleontologist ReBecca Hunt-Foster.

They were first discovered in 2009 by a resident. Since then, paleontologists led by a team at the University of Colorado at Denver have studied them and prepared them to go on display for the general public.

The tracks include a set of 17 consecutive footprints left by [a] Tyrannosaurus rex ancestor and the imprint of an ancient crocodile pushing off into the water.

The site is one of the largest areas of dinosaur tracks from the early Cretaceous period known to exist in North America, she said.

“We don’t usually get this,” said Hunt-Foster, a paleontologist for 16 years. “It is a beautiful track site, one of the best ones I’ve ever seen.”

There are footprints from duckbilled dinosaurs, prehistoric birds, long-necked plant eaters and a dromaeosaur similar to a velociraptor or Utahraptor that had long, sharp claws.

In one rock formation, a footprint left behind by a large plant eater is right in the middle of prints from a meat-eating theropod, Hunt-Foster said.

The imprint of an ancient crocodile shows the chest, body, tail and one foot. Paleontologists believe it was made while the crocodile was pushing off a muddy bank into water.

Paleontologists believe the tracks were made over several days in what was a shallow lake. They likely became covered by sediment that filled them up quickly enough to preserve them but gently enough not to scour them out, Hunt-Foster said. Over time, as more sediment built up, they became rock. They’re near a fault line, where the land has moved up and down over the years, she said. Rain slowly eroded away layers of the rock, exposing the footprints.

Welsh Jurassic mammals feeding, new study


This video says about itself:

There Are No Transitional Fossils?

19 April 2011

Long-sought fossil mammal with transitional middle ear found in China.

Palaeontologists have announced the discovery of Liaoconodon hui, a complete fossil mammal from the Mesozoic found in China that includes the long-sought transitional middle ear.

The specimen was found by palaeontologists from the American Museum of Natural History and the Chinese Academy of Sciences.

It shows the bones associated with hearing in mammals, the malleus, incus, and ectotympanic, decoupled from the lower jaw, as had been predicted, but were held in place by an ossified cartilage that rested in a groove on the lower jaw.

People have been looking for this specimen for over 150 years since noticing a puzzling groove on the lower jaw of some early mammals,” Jin Meng, curator in the Division of Palaeontology at the Museum and first author of the paper, said.

“Now we have cartilage with ear bones attached, the first clear paleontological evidence showing relationships between the lower jaw and middle ear,” Meng revealed

The transition from reptiles to mammals has long been an open question, although studies of developing embryos have linked reptilian bones of the lower jaw joint to mammalian middle ear bones.

The new fossil, Liaoconodon hui, fills the gap in knowledge between the basal, early mammaliaforms like Morganucodon, where the middle ear bones are part of the mandible and the definitive middle ear of living and fossil mammals.

Liaoconodon hui is a medium-sized mammal for the Mesozioc (35.7 cm long from nose to tip of tail, or about 14 inches) and dates from 125 to 122 million years.

It is named in part for the bountiful fossil beds in Liaoning, China, where it was found.

The species name, hui, honours palaeontologist Yaoming Hu who graduated from the American Museum of Natural History-supported doctoral program and recently passed away.

The fossil is particularly complete, and its skull was prepared from both dorsal and ventral sides, allowing Meng and colleagues to see that the incus and malleus have detached from the lower jaw to form part of the middle ear.

These bones remain linked to the jaw by the ossified Meckels cartilage that rests in the groove on the lower jaw. The team hypothesizes that in this early mammal, the eardrum was stabilized with the ossified cartilage as a supporting structure.

“Before we did not know the detailed morphology of how the bones of the middle ear detached, or the purpose of the ossified cartilage,” Meng said.

“Liaoconodon hui changes previous interpretations because we now know the detailed morphology of the transitional mammal and can propose that the ossified cartilage is a stabilizer.

“I”ve always dreamed of a fossil with a good ear ossicle. Now, we have had this once in a lifetime discovery,” Meng added.

From the University of Southampton in England:

Jurassic mammals were picky eaters, new study finds

August 20, 2014

Summary:

New analyses of tiny fossil mammals from Glamorgan, South Wales are shedding light on the function and diets of our earliest ancestors, a team reports. Mammals and their immediate ancestors from the Jurassic period (201-145 million years ago) developed new characteristics – such as better hearing and teeth capable of precise chewing.

New analyses of tiny fossil mammals from Glamorgan, South Wales are shedding light on the function and diets of our earliest ancestors, a team including researchers from the University of Southampton report today in the journal Nature. Mammals and their immediate ancestors from the Jurassic period (201-145 million years ago) developed new characteristics — such as better hearing and teeth capable of precise chewing.

By analysing jaw mechanics and fossil teeth, the team were able to determine that two of the earliest shrew-sized mammals, Morganucodon and Kuehneotherium, were not generalised insectivores but had already evolved specialised diets, feeding on distinct types of insects.

Lead author, Dr Pamela Gill of the University of Bristol, said: “None of the fossils of the earliest mammals have the sort of exceptional preservation that includes stomach contents to infer diet, so instead we used a range of new techniques which we applied to our fossil finds of broken jaws and isolated teeth. Our results confirm that the diversification of mammalian species at the time was linked with differences in diet and ecology.”

The team used synchrotron X-rays and CT scanning to reveal in unprecedented detail the internal anatomy of these tiny jaws, which are only 2cm in length. As the jaws are in many pieces, the scans were ‘stitched together’ to make a complete digital reconstruction. Finite element modelling, the same technique used to design hip joints and bridges, was used to perform a computational analysis of the strength of the jaws. This showed that Kuehneotherium and Morganucodon had very different abilities for catching and chewing prey.

Study co-author, Dr Neil Gostling from the University of Southampton, said: “The improvement in CT scanning, both in the instrumentation, at Light Source at the Paul Scherrer Institute in Switzerland where we scanned or even the µ-VIS Centre at Southampton, along with access for research of this kind, allows us to make inroads into understanding the biology and the ecology of animals long dead. The questions asked of the technology do not produce ‘speculation’, rather the results show a clearly defined answer based on direct comparison to living mammals. This would not be possible without the computational techniques we have used here.”

Using an analysis previously carried out on the teeth of present-day, insect-eating bats, the researchers found that the teeth of Morganucodon and Kuehneotherium had very different patterns of microscopic pits and scratches, known as ‘microwear’. This indicated they were eating different things with Morganucodon favouring harder, crunchier food items such as beetles while Kuehneotherium selected softer foods such as scorpion flies which were common at the time.

Team leader, Professor Emily Rayfield from the University of Bristol, added: “This study is important as it shows for the first time that the features that make us unique as mammals, such as having only one set of replacement teeth and a specialised jaw joint and hearing apparatus, were associated with the very earliest mammals beginning to specialise their teeth and jaws to eat different things.”

‘Butterfly-headed’ pterosaurs discovery in Brazil


A new species of flying reptile from the Cretaceous Era, Caiuajara dobruskiii, has been unearthed in southern Brazil. The creature, described in a 2014 PLOS ONE paper, sported a bony crest on its head. Credit: Maurilio Oliveira/Museu Nacional-UFRJ

From Live Science:

Flock of Ancient ‘Butterfly-Headed’ Flying Reptiles Discovered

By Tia Ghose, Staff Writer

August 13, 2014 02:00pm ET

An ancient flying reptile with a bizarre, butterflylike head has been unearthed in Brazil.

The newfound reptile species, Caiuajara dobruskii, lived about 80 million years ago in an ancient desert oasis. The beast sported a strange bony crest on its head that looked like the wings of a butterfly, and had the wingspan needed to take flight at a very young age.

Hundreds of fossils from the reptile were unearthed in a single bone bed, providing the strongest evidence yet that the flying reptiles were social animals, said study co-author Alexander Kellner, a paleontologist at the Museu Nacional/Universidade Federal do Rio de Janeiro in Brazil. [See Images of the Bizarre 'Butterfly Head' Reptile]

Rare find

Though pterosaur fossils have been unearthed in northern Brazil, no one knew of pterosaurs fossils in the southern part of the country. In the 1970s, a farmer named Dobruski and his son discovered a massive Cretaceous Period bone bed in Cruzeiro do Oeste in southern Brazil, a region not known for any fossils, Kellner said. The find was forgotten for decades, and then rediscovered just two years ago. The team dubbed the reptile Caiuajara dobruskii, after the geologic formation, called the Caiuá Group, where it was found, as well as the farmer who discovered the species, Kellner said.

C. dobruskii belonged to a group of winged reptiles known as pterosaurs, which are more commonly known as pterodactyls.

Hundreds of bone fragments from the species were crammed in an area of just 215 square feet (20 square meters). At least 47 individuals — and possibly hundreds more — were buried at the site. All but a few were juveniles, though the researchers found everything from youngsters with wingspans of just 2.1 feet (0.65 m) long to adults with wingspans reaching 7.71 feet (2.35 m). The fossils weren’t crushed, so the 3D structure of the animals was preserved, the authors wrote in a research article published today (Aug. 13) in the journal PLOS ONE.

The ancient reptiles’ bony crests changed in size and orientation as the pterosaurs grew.

Because the adult skeletal size (other than the head) wasn’t much different from the juveniles’, the researchers hypothesized that C. dobruskii was fairly precocious and could fly at a young age, Kellner said.

Water congregation

Based on the sediments in which the bones were found, the area was once a vast desert with a central oasis nestled between the sand dunes, the authors wrote in the paper.

Ancient C. dobruskii colonies may have lived around the lake for long periods of time and died during periods of drought or during storms. As the creatures died, the occasional desert storm would wash their remains into the lake, where the watery burial preserved them indefinitely, the researchers said. Another possibility is that the pterosaurs stopped at this spot during ancient migrations, though the authors suspect that is less likely.

The bone bed, with its hundreds of individuals in well-dated geological layers, is some of the strongest evidence yet that the fruit-eating animals were social, Kellner said.

“This was a flock of pterosaurs,” Kellner told Live Science.

This finding, in turn, strengthens evidence that other pterosaur species may have been social as well, the authors wrote in the paper.

Dinosaurs got extinct, how about dinosaur age plants?


This video says about itself:

The Day The Mesozoic Died HD

30 May 2013

The disappearance of the dinosaurs at the end of the Cretaceous period posed one of the greatest, long-standing scientific mysteries. This three-act film tells the story of the extraordinary detective work that solved it. Shot on location in Italy, Spain, Texas, Colorado, and North Dakota, the film traces the uncovering of key clues that led to the stunning discovery that an asteroid struck the Earth 66 million years ago, triggering a mass extinction of animals, plants, and even microorganisms. Each act illustrates the nature and power of the scientific method. Representing a rare instance in which many different disciplines—geology, physics, biology, chemistry, paleontology—contributed to a revolutionary theory, the film is intended for students in all science classes.

From Laelaps blog today:

Planting the Cenozoic Garden

by Brian Switek

Sixty six million years ago, a global catastrophe extinguished the non-avian dinosaurs. This is common knowledge. It’s also too narrow a view. Various forms of life disappeared in the same geologic instant – from coil-shelled ammonites to some forms of mammal – and others, for reasons as yet unknown, survived.

Plants are among the neglected of the victims and survivors. A magnolia tree does not hold the same cultural cachet as Tyrannosaurus. The post-impact “fern spike” is often cited as a symbol of wide-ranging devastation, but, outside technical journals, that’s about the extent of our attention span for paleoflora. That’s a shame. If we’re going to understand how life on Earth was so deeply wounded 66 million years ago, and how it bounced back, we should be looking more closely at the prehistoric garden.

Hot on the heels of a review summarizing the global dinosaurian picture at the end of the Cretaceous, Lund University paleobotanists Vivi Vajda and Antoine Bercovici have now assembled a view of how plants were affected by the Earth’s fifth mass extinction. Prehistoric pollen and spores tell the story.

The advantage of looking at fossil pollen, Vajda and Bercovici write, is that there’s plenty of it. That’s not only because plants produce large amounts of the reproductive material, but because pollen is also incredibly durable. If you want to see who’s living where, and how environments change through time, these microscopic plant fossils are good way to do it.

In some ways, the story of the Cretaceous plants echoes what paleontologists have found among other forms of life. The Cretaceous world was a highly-dynamic one marked by fluctuating sea levels, the further breakup of continents, and the formation of new mountain ranges. All this moving and shuffling created evolutionary pockets where new species could evolve in relative isolation, becoming restricted to their particular province. Plants proliferated and evolved according to these boundaries just as dinosaurs did.

Each of the pollen provinces, outlined by Vajda and Bercovici, have their own distinctive profile. In northern North America, Asia, and a few spots in South America, Late Cretaceous sediments commonly contain Aquilapollenites – pollen thought to have come from a group of plants closely related to the modern sandalwood. A neighboring province – stretching from eastern North America to the Himalayas – is dominated by pollen from a Cretaceous birch relative, while rocks from the same time in northern South America, central Africa, and India are rife with pollen from palms. Rounding out the set, a southern hemisphere swath has plenty of pollen from plants related to southern beeches and shrubs.

These were not the only plants to exist in those areas, of course, but their pollen broadly delineates differentiated patches. Paleobotanists can zoom in from there, and, as with dinosaurs, the best-studied sites on the planet document the end of the Cretaceous through the beginning of the Paleogene in western North America.

The forests that Tyrannosaurus and Triceratops knew were dominated by angiosperms – flowering plants – with some conifers, ferns, ginkgos, and cycads for good measure. Palm trees stood alongside evergreens and towered above a shrubby understory in these Late Cretaceous forests. In the aftermath of the impact 66 million years ago, however, those forests were replaced by a relatively small collection of angiosperms, a shadow of the diversity that the Edmontosaurus and kin knew.

Plants suffered extinctions just as many other forms of life did. In fact, some of them dwindle to nothing right at the K-Pg boundary are called “K-species” or “K-taxa.” In the pollen record of North America, for example, the sandalwood relative and a suite of species in seven other genera give way to species in just two genera. Overall, about 60% of plant species present in Cretaceous North America went extinct. The rest of the globe reflects a similar pattern, albeit with different species. Many pollen-producing plants either went entirely extinct or became much less abundant.

Clues from the earliest days of the Paleogene track how plant life eventually bounced back. While sites in New Zealand preserve a “fungal spike” from when mushrooms and their ilk thrived on decomposing matter under blacked-out skies, the subsequent “fern spike” records when pioneering plants – primarily ferns – quickly spread as sunlight began to return. The angiosperms, as well as some conifers, followed, but with fewer species than before. Depending on the location, plant life took between one and ten million years to recover to pre-extinction levels of diversity.

As with the animals, though, why some plants went extinct and others persisted is a mystery. Perhaps some were simply lucky enough to grow in places that were less affected by the devastation following the asteroid strike. Then again, Vajda and Bercovici point out, some researchers have suggested that plants carrying additional sets of chromosomes – or were polyploid – might have had the genetic flexibility to more quickly adapt after ecological shock.

Discerning what made a survivor isn’t just an exercise in replaying ancient history, though.

Vajda and Bercovici argue that two previous mass extinctions – roughly 251 and 200 million years ago – follow a similar pattern of a highly-diverse flora being pruned back, followed by crisis species, pioneer communities, and ecosystem recovery in sequence. Which left me to wonder if we’re going to see this pattern again. If  we’re not yet in a Sixth Extinction, we’re close, and identifying likely survivors verses vulnerable species is an essential part of conservation triage. By sifting through the past, down to the tiniest pollen grain, we can reflect on what sort of future we want to create.

Reference:

Vajda, V., Bercovici, A. 2014. The global vegetation pattern across the Cretaceous-Paleogene mass extinction interval: A template for other extinction events. Global and Planetary Change. doi: 10.1016/j.gloplacha.2014.07.014

Tyrannosaurs hunted in packs?


This video is called Tyrannosaur Rivalry – Planet Dinosaur – Episode 3 – BBC One.

From daily The Guardian in Britain:

Researchers find first sign that tyrannosaurs hunted in packs

Discovery of three sets of dinosaur trackways in Canada reveals that predators were running together

Ian Sample, science editor

Wednesday 23 July 2014 19.36 BST

The collective noun is a terror of tyrannosaurs: a pack of the prehistoric predators, moving and hunting in numbers, for prey that faced the fight of its life.

That tyrannosaurs might have hunted in groups has long been debated by dinosaur experts, but with so little to go on, the prospect has remained firmly in the realm of speculation.

But researchers in Canada now claim to have the strongest evidence yet that the ancient beasts did move around in packs.

At a remote site in the country’s northeast, they uncovered the first known tyrannosaur trackways, apparently left by three animals going the same way at the same time.

Unlike single footprints which have been found before, tyrannosaur trackways are made up of multiple steps, revealing the length of stride and other features of the animal’s movement. What surprised the Canadian researchers was the discovery of multiple tracks running next to each other – with each beast evidently keeping a respectable distance from its neighbour.

Richard McCrea at the Peace Region Palaeontology Research Centre in British Columbia was tipped off about one trackway in October 2011 when a hunting guide working in the area emailed him some pictures. The guide had found one footprint that was already exposed and later uncovered a second heading in the same direction. McCrea made immediate plans to investigate before the winter blanketed the site with snow.

He arrived later the same month and found a third footprint that belonged to the same trackway under volcanic ash. But the real discovery came a year later, when the team returned and uncovered two more sets of tyrannosaur tracks running in the same south-easterly direction.

“We hit the jackpot,” said McCrea. “A single footprint is interesting, but a trackway gives you way more. This is about the strongest evidence you can get that these were gregarious animals. The only stronger evidence I can think of is going back in a time machine to watch them.”

The footprints were so well-preserved that even the contours of the animals’ skin were visible. “You start wondering what it would have been like to have been there when the tracks were made. The word is terror. I wouldn’t want to meet them in a dark alley at night,” McCrea said.

From the size of the footprints, the researchers put the beasts in their late 20s or early 30s – a venerable age for tyrannosaurs. The depth of the prints and other measurements suggest the tracks were left at the same time. They date back to nearly 70m years ago.

Close inspection of the trackways found that the tyrannosaur that left the first set of prints had a missing claw from its left foot, perhaps a battle injury. Details of the study are published in the journal Plos One.

During the expedition, McCrea’s team unearthed more prehistoric footprints from other animals, notably hadrosaurs, or duck-billed dinosaurs. Crucially, these were heading in all sorts of directions, evidence, says McCrea, that the tyrannosaurs chose to move as a pack, and were not simply forced into a group by the terrain.

“When you find three trackways together, going in same direction, it’s not necessarily good evidence for gregarious behaviour. They could be walking along a shore. But if all the other animals are moving in different directions, it means there is no geographical constraint, and it strengthens the case,” said McCrea.

Four-winged Chinese dinosaur discovery


This video says about itself:

Reptiles of the Skies – Walking with Dinosaurs in HQ – BBC

9 November 2012

The Cretaceous period saw the breaking up of the northern and southern landmasses. Flying dinosaurs like Tapejara would master the air and the new coast lines of prehistoric Earth. The largest flying dinosaur Ornithocheirus prepares for a long flight to breeding grounds.

However, this video is about pterosaurs: flying non-dinosaurs, living at the same time as dinosaurs.

From daily The Guardian in Britain:

Four-winged flying dinosaur unearthed in China

Newly discovered Changyuraptor yangi lived 125m years ago and was like ‘a big turkey with a really long tail’

Nishad Karim

Tuesday 15 July 2014 17.18 BST

A new species of prehistoric, four-winged dinosaur discovered in China may be the largest flying reptile of its kind.

The well-preserved, complete skeleton of the dinosaur Changyuraptor yangi features a long tail with feathers 30cm in length – the longest ever seen on a dinosaur fossil. The feathers may have played a major role in flight control, say scientists in the latest issue of Nature Communications, in particular allowing the animal to reduce its speed to land safely.

The 125m-year-old fossil, believed to be an adult, is completely covered in feathers, including long feathers attached to its legs that give the appearance of a second set of wings or “hind wings”. It is the largest four-winged dinosaur ever found, 60% larger than the previous record holder, Microraptor zhaoianus, in the family of dinosaurs known as microraptors.

These beasts were smaller versions of their closely related, larger cousins, the velociraptors made famous in the Jurassic Park movies. They belong to an even wider group including the king of all dinosaurs, Tyrannosaurus rex. At 1.3 metres long and weighing 4kg, the meat-eating C. yangi is one of the largest members of the microraptor family, which tended to weigh 1kg or less.

Microraptors, which are close relatives of modern birds, had many anatomical features that are now only seen in birds, such as hollow bones, nesting behavior, feathers and possibly flight. They were dinosaurs rather than pterosaurs, the more well known flying prehistoric reptiles.

C. yangi was [like] a big turkey with a really long tail,” said Dr Alan Turner from Stony Brook University, one of the authors of the paper. “We don’t know for sure if C. yangi was flying or gliding, but we can sort of piece together this bigger model by looking at what its tail could do. Whether or not this animal could fly is part of a bigger puzzle and we’re adding a piece to that puzzle.”

The fossil was discovered in Liaoning province, northeastern China, an area noted for the large number of feathered dinosaurs found over the past decade, including the first widely acknowledged feathered dinosaur, Sinosauropteryx prima, in 1996.

Before this study, it was thought that the small size of microraptors was a key adaptation needed for flight, but the discovery of C. yangi suggests that aerial ability was not restricted to smaller animals in this group.

See also here.

New horned dinosaur discovery in North America


This video is called Meet Mercuriceratops gemini.

From Tech Times:

Meet Mercuriceratops gemini, a horned-dinosaur with a Roman god’s helmet

By Alexander Saltarin, Tech Times

June 19, 11:13 AM

Scientists have discovered and named a new type of horned dinosaur. Due to the frills on the dinosaur resembling the wings usually found on the helmet of Mercury in depictions of the Roman god, the scientists decided to christen the dinosaur as Mercuriceratops gemini.

The discovery was made after a team of scientists analyzed and studied fossils found in two locations in North America. Some of the fossils were found in Alberta, Canada while the others were found in the state of Montana. Analysis of the fossils showed that the new horned dinosaur would have weighed as much as 2 tons and would have grown to a length of around 20 feet. However, the most distinct feature of the Mercuriceratops is its unique frill. The later part of the scientific name “Gemini” is a reference to the fact that two similar fossils were found in two different locations.

“Mercuriceratops took a unique evolutionary path that shaped the large frill on the back of its skull into protruding wings like the decorative fins on classic 1950s cars,” said Cleveland Museum of Natural History curator of vertebrate paleontology Michael Ryan. “It definitively would have stood out from the herd during the Late Cretaceous.”

Ryan is also the lead author of a paper on the subject published in the online journal Naturwissenschaften.

Scientists believe that the Mercuriceratops thrived during the Late Cretaceous Period approximately 77 million years ago. The name the scientists have chosen literally means “Mercury horned-face,” which aptly described the way the dinosaur’s face would have appeared. The fossil samples found in Canada were discovered in the Dinosaur Provincial Park in Alberta. The park is considered as a UNESCO World Heritage Site and many discoveries have been made in the area. The American fossil on the other hand was found in the north central part of Montana.

The new dinosaur was of particular interest to paleontologists due to the fact that the shape of its skull was unlike any other dinosaur previously known. A dinosaur’s frill, which is often referred to as a neck shield, protects the necks of some dinosaurs like the Triceratops and the newly discovered Mercuriceratops from predators during attacks. The butterfly shaped frill found on the Mercuriceratops shows that evolution had numerous tricks up its sleeves in terms of dinosaur morphology.