Herbivore dinosaurs’ food, new research


This May 2018 video says about itself:

Check out the largest herbivorous dinosaurs that ever lived! This top 10 list of plant eating dinosaurs has some of the biggest creatures that ever roamed the earth millions of years ago!

From the University of Leeds in England:

Growing a dinosaur’s dinner

July 13, 2018

Scientists have measured the nutritional value of herbivore dinosaurs‘ diet by growing their food in atmospheric conditions similar to those found roughly 150 million years ago.

Previously, many scientists believed that plants grown in an atmosphere with high carbon dioxide levels had low nutritional value. But a new experimental approach led by Dr Fiona Gill at the University of Leeds has shown this is not necessarily true.

The team grew dinosaur food plants, such as horsetail and ginkgo, under high levels of carbon dioxide mimicking atmospheric conditions similar to when sauropod dinosaurs, the largest animals ever to roam Earth, would have been widespread.

An artificial fermentation system was used to simulate digestion of the plant leaves in the sauropods‘ stomachs, allowing the researchers to determine the leaves’ nutritional value. The findings, published in Palaeontology, showed many of the plants had significantly higher energy and nutrient levels than previously believed.

This suggests that the megaherbivores would have needed to eat much less per day and the ecosystem could potentially have supported a significantly higher dinosaur population density, possibly as much as 20% greater than previously estimated.

Dr Gill, a palaeontologist and geochemist from the School of Earth and Environment at Leeds, said: “The climate was very different in the Mesozoic era — when the huge brachiosaurus and diplodocus lived — with possibly much higher carbon dioxide levels. There has been the assumption that as plants grow faster and/or bigger under higher CO2 levels, their nutritional value decreases. Our results show this isn’t the case for all plant species.

“The large body size of sauropods at that time would suggest they needed huge quantities of energy to sustain them. When the available food source has higher nutrient and energy levels it means less food needs to be consumed to provide sufficient energy, which in turn can affect population size and density.

“Our research doesn’t give the whole picture of dinosaur diet or cover the breadth of the plants that existed at this time, but a clearer understanding of how the dinosaurs ate can help scientists understand how they lived.”

“The exciting thing about our approach to growing plants in prehistoric atmospheric conditions is that it can used to simulate other ecosystems and diets of other ancient megaherbivores, such as Miocene mammals — the ancestors of many modern mammals.”

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Long-necked dinosaurs, why so big?


This video says about itself:

Argentinian researchers discover the oldest giant dinosaur species that inhabited the Earth

9 July 2018

Scientists presented Ingentia prima, the first giant dinosaur that inhabited the planet more than 200 million years ago. It exceeds three times the size of the largest Triassic dinosaurs known to date. The discovery was made at the Balde de Leyes deposit, southeast of the province of San Juan.

By Carolyn Gramling, 11:49am, July 10, 2018:

Long-necked dinosaurs grew to be giants in more ways than one

Fossils suggest some early sauropod relatives grew massive using a previously unknown method

For sauropods — the largest animals known to have walked on Earth — there may have been more than one way to get gigantic.

Most early relatives of the herbivorous dinosaurs have a suite of features once thought to be the essential blueprint for gigantism, such as sturdy pillarlike legs, elongated necks and forelimbs, and bones that grew continuously rather than in seasonal spurts. But an analysis of fossils of sauropodomorphs — a group that includes sauropods and some ancestors and similarly shaped relatives— suggests that some of the dinos may have had a different strategy for becoming behemoths, researchers report online July 9 in Nature Ecology and Evolution.

Paleontologist Cecilia Apaldetti of the Universidad Nacional de San Juan in Argentina and colleagues examined four sauropodomorphs, including one newly identified species that the team dubbed Ingentia prima and three already known specimens of a sauropodomorph called Lessemsaurus sauropoides. Dating to the Late Triassic, between 237 million and 201 million years ago, these “Lessemsauridae” were far from puny: The animals weighed in at an estimated 7 to 10 metric tons, larger than an African elephant.

All four specimens showed a combination of features that was distinct from sauropods as well as from other sauropodomorphs. Instead of upright, pillarlike legs, the dinos had crouched hind limbs and flexed front limbs, with elbows splayed slightly outward. Patterns of bone growth in the fossils also suggest that the animals grew in cyclical spurts rather than continuously. However, their bone growth was extremely rapid, a feature unique to this group, Apaldetti says. “They grew in a cyclical but extremely accelerated growth, at a speed even higher than that of the giants that grew continuously.”

Like later sauropods, I. prima and L. sauropoides also appear to have had a birdlike respiratory system, the researchers found. Air sacs within the animals’ vertebrae provided large reserves of oxygenated air, helped keep their bodies cool despite their large size, and lightened the weight of their vertebrae.

Martin Sander, a vertebrate paleontologist at Universität-Bonn in Germany, says that I. prima presents the best proof yet that these sauropodomorphs had this birdlike respiratory system, a fact that wasn’t previously determined. However, he says he is not convinced that the Lessemsauridae were on a separate track toward gigantism. “For me, it’s more of an intermediate stage”, Sander says.

That sentiment is echoed by Jeffrey Wilson, a vertebrate paleontologist at the University of Michigan in Ann Arbor. Lessemsauridae bone growth was cyclical, but that doesn’t necessarily mean the cycles were seasonal; there may have been long time lags in between growth spurts, part of a transition to more sauropod-like growth patterns, Wilson says. “One of the things I think future work will do is help resolve the ambiguity over whether the Lessemsauridae were taking their own adventure into gigantism.”

The Lessemsauridae may have developed their growth strategy some 30 million years earlier than Jurassic sauropods, such as Brachiosaurus and Diplodocus, Apaldetti notes. But ultimately, the Jurassic giants “were more successful”, she says — they outweighed the sauropodomorphs by as much as 60 tons, and outlasted them by tens of millions of years.

Tyrannosaurus rex’s short arms, why?


This 26 June 2018 video says about itself:

Tyrannosaurus rex was big, Tyrannosaurus rex was vicious, and Tyrannosaurus rex had tiny arms. The story of how T-Rex lost its arms is, itself, pretty simple. But the story of why it kept those little limbs, and how it used them? Well, that’s a little more complicated.

Dinosaur tongues, new research


This 2017 video is called How to Sculpt a Dinosaur Part 2 – Eyes, Teeth, Tongue & Skin Texture – PREVIEW.

From the University of Texas at Austin in the USA:

T. Rex couldn’t stick out its tongue

June 20, 2018

Dinosaurs are often depicted as fierce creatures, baring their teeth, with tongues wildly stretching from their mouths like giant, deranged lizards. But new research reveals a major problem with this classic image: Dinosaurs couldn’t stick out their tongues like lizards. Instead, their tongues were probably rooted to the bottoms of their mouths in a manner akin to alligators.

Researchers from The University of Texas at Austin and the Chinese Academy of Sciences made the discovery by comparing the hyoid bones — the bones that support and ground the tongue — of modern birds and crocodiles with those of their extinct dinosaur relatives. In addition to challenging depictions of dino tongues, the research proposes a connection on the origin of flight and an increase in tongue diversity and mobility.

The research was published June 20 in the journal PLOS ONE.

“Tongues are often overlooked. But, they offer key insights into the lifestyles of extinct animals,” said lead author Zhiheng Li, an associate professor at the Key Laboratory of Vertebrate Evolution and Human Origins of the Chinese Academy of Sciences.He conducted the work while earning his Ph.D. at the UT Jackson School of Geosciences.

The researchers made their discovery by comparing the hyoid bones of extinct dinosaurs, pterosaurs and alligators to the hyoid bones and muscles of modern birds and alligator specimens. Hyoid bones act as anchors for the tongue in most animals, but in birds these bones can extend to the tip. Because extinct dinosaurs are related to crocodiles, pterosaurs and modern birds, comparing anatomy across these groups can help scientists understand the similarities and differences in tongue anatomy and how traits evolved through time and across different lineages.

The comparison process involved taking high-resolution images of hyoid muscles and bones from 15 modern specimens, including three alligators and 13 bird species as diverse as ostriches and ducks, at the Jackson School’s High-Resolution X-Ray Computed Tomography Facility (UTCT). The fossil specimens, most from northeastern China, were scrutinized for preservation of the delicate tongue bones and included small bird-like dinosaurs, as well as pterosaurs and a Tyrannosaurus rex.

The results indicate that hyoid bones of most dinosaurs were like those of alligators and crocodiles — short, simple and connected to a tongue that was not very mobile. Co-author and Jackson School Professor Julia Clarke said that these findings mean that dramatic reconstructions that show dinosaurs with tongues stretching out from between their jaws are wrong.

“They’ve been reconstructed the wrong way for a long time”, Clarke said. “In most extinct dinosaurs their tongue bones are very short. And in crocodilians with similarly short hyoid bones, the tongue is totally fixed to the floor of the mouth.”

Clarke is no stranger to overturning dinosaur conventions. Her 2016 study on dinosaur vocalizations found evidence that large dinosaurs might make booming or cooing sounds, similar to the sounds made by crocodiles and ostriches.

In contrast to the short hyoid bones of crocodiles, the researchers found that pterosaurs, bird-like dinosaurs, and living birds have a great diversity in hyoid bone shapes. They think the range of shapes could be related to flight ability, or in the case of flightless birds such as ostriches and emus, evolved from an ancestor that could fly. The researchers propose that taking to the skies could have led to new ways of feeding that could be tied to diversity and mobility in tongues.

“Birds, in general, elaborate their tongue structure in remarkable ways”, Clarke said. “They are shocking.”

That elaboration could be related to the loss of dexterity that accompanied the transformation of hands into wings, Li said.

“If you can’t use a hand to manipulate prey, the tongue may become much more important to manipulate food”, Li said. “That is one of the hypotheses that we put forward.”

The scientists note one exception linking tongue diversity to flight. Ornithischian dinosaurs — a group that includes Triceratops, ankylosaurs and other plant-eating dinosaurs that chewed their food — had hyoid bones that were highly complex and more mobile, though they were structurally different from those of flying dinosaurs and pterosaurs.

Further research on other anatomical changes that occurred with shifts in tongue function could help improve our knowledge of the evolution of birds, Clarke said, giving an example of how changes in the tongues of living birds are associated with changes in the position of the opening of the windpipe. These changes could in turn affect how birds breathe and vocalize.

However, the researchers note that the fossil record as yet can’t pin down when these changes to the windpipe occurred.

“There is more work to be done,” Li said.

The study was funded by the Chinese Academy of Sciences, The University of Texas at Austin, the Smithsonian Institution and the Gordon and Betty Moore Foundation.

Jurassic World new film, comments


This video from the USA says about itself:

Thoughts on Jurassic World: Fallen Kingdom (NO SPOILERS)

10 June 2018

Here’s how we felt about Jurassic World: Fallen Kingdom, the newest continuation of my favourite film of all time! This is a very subjective review as we’re talking about our opinions of the film, and you probably won’t agree with everything we say. We also don’t talk about any major plot points that haven’t been shown in trailers here, so don’t worry about spoilers!

BBC: The plot might be ludicrous and the CGI below par, but the latest dinosaur blockbuster is ‘good old-fashioned summer entertainment’, according to Nicholas Barber.

“Jurassic World: Fallen Kingdom” enjoyed a monster opening weekend, topping $150 million from cinemas across the U.S. and $700 million worldwide.

Baby spinosaurus dinosaur discovery


This video says about itself:

Almost a century ago, paleontologists found the first tantalizing hints of a monster even bigger than Tyrannosaurus rex, perhaps the largest predator ever to live.

Newly discovered fossils revealed that Spinosaurus, bigger than T. rex, was an excellent swimmer, unlike any other dinosaur.

Found in the sands of Morocco. Paleontologist and National Geographic Emerging Explorer Nizar Ibrahim weaves together clues from the Cretaceous period, Nazi Germany, and present-day Africa.

Bigger Than T Rex – HD Documentary (2015).

From PeerJ:

The smallest biggest theropod dinosaur

A new fossil from Africa represents a small juvenile individual of the huge sail-backed Spinosaurus

May 30, 2018

Spinosaurus is the longest, and among the largest predatory dinosaurs, and possesses many adaptations for a semiaquatic lifestyle. A tiny claw phalanx of the foot, discovered in Cretaceous-aged sandstones of the Sahara, shows a peculiar shape compatible with an early juvenile Spinosaurus. As reported in PeerJ — the Journal of Life & Environmental Sciences, the fossil is from the smallest known individual of this giant, sail-backed theropod. The findings suggest the small specimen retains the same locomotor adaptations as the large version — such as traversing soft substrates or paddling — during the entire lifespan.

Collected in Morocco in 1999, a 21 mm-long pedal ungual phalanx (a phalanx supporting a claw of the foot) remained unnoticed in the Paleontological Collection of the Natural History Museum of Milan, until the recent discovery (2014) of a new partial skeleton of Spinosaurus aegyptiacus, that preserves an almost complete right foot with peculiar morphology in the phalanges.

The striking similarities with the claw phalanges of the foot of Spinosaurus allowed palaeontologists Simone Maganuco and Cristiano Dal Sasso to identify the tiny bone to a very small and young specimen of the sail-backed Spinosaurus, the smallest individual reported up to today. “Besides the rarity of the fossils belonging to juvenile theropod dinosaurs, and the rarity of Spinosaurus bones, this finding is even more remarkable if we consider the dramatic size attained by some large specimens of Spinosaurus, which are possibly the longest, and among the largest predatory dinosaurs ever found”- says Maganuco.

Assuming the juveniles looked like smaller versions of the adults, the 21 mm-long claw phalanx from this small specimen would pertain to an early juvenile individual, 1.78 m-long, only just a little bit longer than the estimated length of the sole head of the largest adult Spinosaurus known to date, which is also housed at the Natural History Museum of Milan.

According to recent studies, the broader than deep unguals in Spinosaurus with their flat plantar surface are reminiscent of the flattened pedal shape of shorebirds that do not perch, and the whole foot may have been adapted to traversing soft substrates or webbed for paddling. “This find indicates that in Spinosaurus the foot of early juveniles had the same locomotor adaptations observed in large individuals, that were probably achieved early in ontogeny and retained for the entire lifespan”, remarks co-author Cristiano Dal Sasso.

After dinosaur extinction, marine life recovery


This video says about itself:

How Asteroids Really Killed The Dinosaurs – Part 1 | Last Days of the Dinosaurs

9 June 2016

In the clip from Last Days of the Dinosaurs we learn how the asteroids really killed the dinosaurs

This video says about itself:

How Asteroids Really Killed The Dinosaurs – Part 2 | Last Day Of The Dinosaurs

2 June 2017

Did you know that if the asteroid that wiped out the dinosaurs from the face of the Earth would have hit another location, they might still be alive? The shallow waters of the Gulf Of Mexico instantly vaporized as the asteroid hit, causing absolute destruction. This was the Last Day Of The Dinosaurs.

Asteroid Day is celebrated every year on the 30th of June.

From the University of Texas at Austin in the USA:

Life recovered rapidly at impact site of dino-killing asteroid

May 30, 2018

Summary: New research finds that life rebounded in the crater left by the asteroid that killed the dinosaurs much faster than previously thought. Sea life was present a few years after the impact and a thriving ecosystem within 30,000 years.

About 66 million years ago, an asteroid smashed into Earth, triggering a mass extinction that ended the reign of the dinosaurs and snuffed out 75 percent of life.

Although the asteroid killed off species, new research led by The University of Texas at Austin has found that the crater it left behind was home to sea life less than a decade after impact, and it contained a thriving ecosystem within 30,000 years — a much quicker recovery than other sites around the globe.

Scientists were surprised by the findings, which undermine a theory that recovery at sites closest to the crater is the slowest due to environmental contaminants — such as toxic metals — released by the impact. Instead, the evidence suggests that recovery around the world was influenced primarily by local factors, a finding that could have implications for environments rocked by climate change today.

“We found life in the crater within a few years of impact, which is really fast, surprisingly fast”, said Chris Lowery, a postdoctoral researcher at the University of Texas Institute for Geophysics (UTIG) who led the research. “It shows that there’s not a lot of predictability of recovery in general.”

The research was published May 30 in the journal Nature. UTIG research scientists Gail Christeson and Sean Gulick and postdoctoral researcher Cornelia Rasmussen are co-authors on the paper, along with a team of international scientists. UTIG is a research unit of the Jackson School of Geosciences.

The evidence for life comes primarily in the form of microfossils — the remains of unicellular organisms such as algae and plankton — as well as the burrows of larger organisms discovered in a rock extracted from the crater during recent scientific drilling conducted jointly by the International Ocean Discovery Program and International Continental Drilling Program.

The tiny fossils are hard evidence that organisms inhabited the crater, but also a general indicator about habitability in the environment years after impact. The swift recovery suggests that other life forms aside from the microscopic were living in the crater shortly after impact.

“Microfossils let you get at this complete community picture of what’s going on,” Lowery said. “You get a chunk of rock and there’s thousands of microfossils there, so we can look at changes in the population with a really high degree of confidence … and we can use that as kind of a proxy for the larger scale organisms.”

The scientists found the first evidence for the appearance of life two to three years after impact. The evidence included burrows made by small shrimp or worms. By 30,000 years after impact, a thriving ecosystem was present in the crater, with blooming phytoplankton (microscopic plants) supporting a diverse community of organisms in the surface waters and on the seafloor. In contrast, other areas around the world, including the North Atlantic and other areas of the Gulf of Mexico, took up to 300,000 years to recover in a similar manner.

The core containing the fossil evidence was extracted from the crater during a 2016 expedition co-led by the Jackson School. In this study, scientists zeroed in on a unique core section that captures the post-impact seafloor in unprecedented detail. Whereas core samples from other parts of the ocean hold only millimeters of material deposited in the moments after impact, the section from the crater used in this study contains more than 130 meters of such material, the upper 30 inches of which settled out slowly from the turbid water. This material provides a record that captures the seafloor environment days to years after the impact.

“You can see layering in this core, while in others, they’re generally mixed, meaning that the record of fossils and materials is all churned up, and you can’t resolve tiny time intervals”, said co-author Timothy Bralower, a micropaleontology professor at Pennsylvania State University. “We have a fossil record here where we’re able to resolve daily, weekly, monthly, yearly changes.”

Ellen Thomas, a senior research scientist in geology and geophysics at Yale University who was not part of the study, said that although she thinks the paper makes a strong case for a speedy recovery, she expects that the larger scientific community will be interested in digging into the data for themselves.

“In my opinion, we will see considerable debate on the character, age, sedimentation rate and microfossil content … especially of the speculation that burrowing animals may have returned within years of the impact”, Thomas said.

The relatively rapid rebound of life in the crater suggests that although the asteroid caused the extinction, it didn’t hamper recovery. The scientists point to local factors, from water circulation to interactions between organisms and the availability of ecological niches, as having the most influence on a particular ecosystem’s recovery rate.

The findings indicate that recovery after a global catastrophe could be a local affair.

The International Ocean Discovery Program, the International Continental Drilling Program, the National Science Foundation and NASA funded the research.