New Mexico dinosaurs, new study


This video is called Theropod cladogram.

From PLOS ONE:

Small Theropod Teeth from the Late Cretaceous of the San Juan Basin, Northwestern New Mexico and Their Implications for Understanding Latest Cretaceous Dinosaur Evolution

Thomas E. Williamson, Stephen L. Brusatte

Published: April 07, 2014

Abstract

Studying the evolution and biogeographic distribution of dinosaurs during the latest Cretaceous is critical for better understanding the end-Cretaceous extinction event that killed off all non-avian dinosaurs. Western North America contains among the best records of Late Cretaceous terrestrial vertebrates in the world, but is biased against small-bodied dinosaurs.

Isolated teeth are the primary evidence for understanding the diversity and evolution of small-bodied theropod dinosaurs during the Late Cretaceous, but few such specimens have been well documented from outside of the northern Rockies, making it difficult to assess Late Cretaceous dinosaur diversity and biogeographic patterns.

We describe small theropod teeth from the San Juan Basin of northwestern New Mexico. These specimens were collected from strata spanning Santonian – Maastrichtian. We grouped isolated theropod teeth into several morphotypes, which we assigned to higher-level theropod clades based on possession of phylogenetic synapomorphies. We then used principal components analysis and discriminant function analyses to gauge whether the San Juan Basin teeth overlap with, or are quantitatively distinct from, similar tooth morphotypes from other geographic areas.

The San Juan Basin contains a diverse record of small theropods. Late Campanian assemblages differ from approximately co-eval assemblages of the northern Rockies in being less diverse with only rare representatives of troodontids and a Dromaeosaurus-like taxon. We also provide evidence that erect and recurved morphs of a Richardoestesia-like taxon represent a single heterodont species.

A late Maastrichtian assemblage is dominated by a distinct troodontid. The differences between northern and southern faunas based on isolated theropod teeth provide evidence for provinciality in the late Campanian and the late Maastrichtian of North America. However, there is no indication that major components of small-bodied theropod diversity were lost during the Maastrichtian in New Mexico. The same pattern [is] seen in northern faunas, which may provide evidence for an abrupt dinosaur extinction.

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Biggest European carnivorous dinosaur discovery in Portugal


Torvosaurus tanneri in Madrid museum

From PLOS ONE:

Torvosaurus gurneyi n. sp., the Largest Terrestrial Predator from Europe, and a Proposed Terminology of the Maxilla Anatomy in Nonavian Theropods

Christophe Hendrickx, Octávio Mateus

Published: March 05, 2014

Abstract

The Lourinhã Formation (Kimmeridgian-Tithonian) of Central West Portugal is well known for its diversified dinosaur fauna similar to that of the Morrison Formation of North America; both areas share dinosaur taxa including the top predator Torvosaurus, reported in Portugal.

The material assigned to the Portuguese T. tanneri, consisting of a right maxilla and an incomplete caudal centrum, was briefly described in the literature and a thorough description of these bones is here given for the first time. A comparison with material referred to Torvosaurus tanneri allows us to highlight some important differences justifying the creation of a distinct Eastern species.

Torvosaurus gurneyi n. sp. displays two autapomorphies among Megalosauroidea, a maxilla possessing fewer than eleven teeth and an interdental wall nearly coincidental with the lateral wall of the maxillary body. In addition, it differs from T. tanneri by a reduced number of maxillary teeth, the absence of interdental plates terminating ventrally by broad V-shaped points and falling short relative to the lateral maxillary wall, and the absence of a protuberant ridge on the anterior part of the medial shelf, posterior to the anteromedial process.

T. gurneyi is the largest theropod from the Lourinhã Formation of Portugal and the largest land predator discovered in Europe hitherto. This taxon supports the mechanism of vicariance that occurred in the Iberian Meseta during the Late Jurassic when the proto-Atlantic was already well formed. A fragment of maxilla from the Lourinhã Formation referred to Torvosaurus sp. is ascribed to this new species, and several other bones, including a femur, a tibia and embryonic material all from the Kimmeridgian-Tithonian of Portugal, are tentatively assigned to T. gurneyi. A standard terminology and notation of the theropod maxilla is also proposed and a record of the Torvosaurus material from Portugal is given.

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Dinosaur exhibition in Minnesota, USA


This video says about itself:

Dinosaur egg fossils – Walking with Dinosaurs: Ballad of Big Al – BBC

Scientists step back 145 million years to tell the story of ‘Big Al’, a complete skeleton of an adolescent Allosaurus found in Wyoming in 1991. The story starts in the Atlantic coast of Portugal where the discovery of remarkable fossils of dinousaur egg shells shed light on how Big Al was born.

From the Post-Bulletin in Minnesota in the USA:

Family Time: Exhibit explores dinosaur family life

Thursday, February 27, 2014 9:32 am

Lindy Lange, life@postbulletin.com

It’s all about family at Quarry Hill Nature Center‘s “Hatching the Past: Dinosaur Eggs & Babies.” With a focus on dinosaur family life, the month-long special exhibit features replicas of baby dinosaurs and dinosaur eggs as well as three life-size pteranodon models.

“Everyone loves dinosaurs and everyone loves babies,” said Pam Meyer, Quarry Hill Nature Center executive director. “This exhibit looks at dinosaur family life, how they cared for their young, and what we can tell about it from fossils and eggs.”

“Hatching the Past” is Quarry Hill’s fifth large-scale fossil exhibit. The first was Stan, the Tyrannosaurus rex, in 2006. Other exhibits included a giant sea turtle, a wooly mammoth and a giant ground sloth. Altogether, nearly 75,000 visitors have enjoyed the exhibits.

“That’s why people enjoy these exhibits so much — they make people think and ask questions. It puts them in the mindset of scientific observation,” Meyer said. “At ‘Hatching the Past,’ there’s a lot for families to explore and learn about.”

The exhibit also features family-friendly dig pits, where kids can practice their junior paleontologist skills, and a giant dinosaur nest, where kids can dress up like a dinosaur and play dinosaur mom and dad.

“We’ve kept admission the same as it’s been for a number of years so it’s affordable and accessible to families,” Meyer said. “And it’s right here in your own backyard at your neighborhood nature center. All proceeds go right back into the nature center. Not only are you going to have a great time, but you’re supporting a great organization.”

The exhibit is open daily. Admission is $3 for adults and $2 for children.

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First dinosaur discovery in Malaysia


This video is called First Malaysian dinosaur fossil found in Pahang: Researchers.

From The Star in Malaysia:

Tuesday February 18, 2014 MYT 11:00:34 AM

Fish-eating dinosaur fossil discovered in Pahang

By Isabelle Lai

PETALING JAYA: Fossil remains of a carnivorous “fish-eating” dinosaur has been discovered in Malaysia, with Universiti Malaya set to unveil the evidence today.

Discovered in the rural interiors of Pahang, the fossil remains of the spinosauridae dinosaur are believed to be from the late Mesozoic era, most likely from the Cretaceous period between 65 million and 145.5 million years ago.

This is believed to be the first time that fossil remains of a dinosaur have been found in Malaysia.

The dinosaur remains had been identified by a team led by Associate Professor Dr Masatoshi Sone of the university’s geology department in collaboration with reptile paleontology specialist Professor Ren Hirayama from Tokyo’s Waseda University.

Spinosauridae is a particular family of carnivorous dinosaurs characterised by its elongated, crocodile-like skulls with conical teeth that had either very tiny or with no serrations.

Another spinosauridae fossil had also been discovered in Australia in 2011, before which the species was believed to have existed only in the northern hemisphere.

Scientists had discovered a 125-million-year-old neck vertebrae identical to that of a Baryonx

sic; Baryonyx

in Victoria, Australia.

Dr Masatoshi will be attending today’s press conference, along with Pahang Mentri Besar Datuk Seri Adnan Yaakob, UM vice-chancellor Professor Datuk Dr Mohd Amin Jalaludin and the Science Faculty dean Professor Datuk Dr Mohd Sofian Azirun.

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Plesiosaur discovery in Chile


This video says about itself:

This animation shows how the juvenile plesiosaur, discovered in Antarctica by an American-Argentine research team, might have appeared.

From I Love Chile News:

Chile’s Loch Ness Monster: New Marine Reptile Fossil Found

February 10 15:28 2014

by Josh King

Paleontologists working in Chile’s Bío Bío region have discovered the fossilized remains of a previously unknown species of marine reptile.

Bío Bío — The fossilized remains of a species of plesiosaur has been discovered by a group of Chilean paleontologists working in the country’s Bío Bío region. The Aristonectes quiriquinensis specimen is over 60 million years old and lived in the seas of the Southern hemisphere as long ago as 251 million years.

That is a confusing sentence. 60 million and 251 million is quite a difference. Aristonectes is said to be from the Late Cretaceous, 100-66 million years ago. So, this species did not exist yet 251 million years ago. And 60 million years ago, all plesiosaurs, like all dinosaurs, had become extinct.

The plesiosaur was a large marine reptile that inhabited all of the world’s oceans. They appeared during the late Cretaceous period,

No, the origin of plesiosaurs is earlier. During the Triassic.

and since being found and named in 1821, over a hundred species have been found. They are probably most well-known in modern popular culture as the template for the Loch Ness Monster, which has the benefit of making this species quite famous and generating interest for the study of ancient creatures, but also often makes people mistake the plesiosaur for a made-up fantasy creature. Much to the dismay of any paleontologist.

This new species was first found in 2001, when only its skull was discovered. In 2009, however, parts of its neck were found and it was seen to have a slightly shorter neck than those found in the Northern Hemisphere. This meant that there was a notable difference between Northern and Southern species.

Having published their findings in the Journal of Vertebrate Paleontology, the paleontologists are now studying the remains to find out why these differences have occurred.

With evidence of new extinct creatures being discovered all the time, such as the large meat-eating dinosaur found last year in Utah, it’s just as exciting as ever to hear about new findings of these ancient giants and beginning to sort out the fantasy from the reality.

The scientific description of the species newly discovered in Chile is here.

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Prehistoric frog’s anti-dinosaur armour?


This video is called The Evolution of Amphibians.

From LiveScience:

Primeval ‘Devil Frog’ May Have Sported Anti-Dinosaur Armor

By Tia Ghose, Staff Writer

January 29, 2014 10:00am ET

An ancient, predatory creature known as the devil frog may have looked even scarier than previously thought.

The monster frog, Beelzebufo ampinga, lived during the Cretaceous Period in what is now Africa, and sported spiky flanges protruding from the back of its skull and platelike armor down its back, almost like a turtle shell.

“We knew it was big; we knew it was almost certainly predatory,” said study co-author Susan Evans, a paleontologist at the University College London. “What the new material has shown us is that it was even more heavily armored than we imagined.”

The massive frog’s spiked body armor may have helped it fend off the dinosaurs and crocodiles that prowled during that time. [See Photos of the Devil Frog and Other Freaky Frogs]

Elusive lineage

The researchers first discovered a few bone fragments from a mystery frog in Madagascar in 1998, but it wasn’t until 2008 that they had enough pieces to identify the species, which they dubbed the devil frog, or Beelzebufo ampinga. The massive frog lived between 70 million and 65 million years ago.

When the team analyzed the frog’s morphology, they found that physically, it fit in with a family of horned frogs called the Ceratophryidae, which are now found only in South America.

But to reach Madagascar from South America, the frogs would have needed to hop along a passageway, possibly through Antarctica, that linked the two landmasses. But that route was submerged underwater by 112 million years ago, Evans said.

That would mean that devil frogs must have diverged from their South American cousins prior to that submergence, pushing back the origin of Ceratophryidae by more than 40 million years, Evans said.

More specimens

Over the course of the next five years, the team found several more bone fragments of Beelzebufo ampinga. In the new study, they combined all of the fragments to do a much more complete reconstruction of the devil frog.

The new analysis confirms the frog’s lineage in the Ceratophryidae family. It also downgrades the amphibian’s size — instead of being the biggest frog that ever lived, it may be closer to the size of an African bullfrog, which grows to about 10 inches (25.4 centimeters) across.

Even so, the analysis reveals that the devil frog was even fiercer-looking than previously thought. Past studies had suggested it had a huge, globular head; sharp teeth; and short back legs, but the spiky flanges and the plates embedded in its skin were a surprising discovery.

The frogs may have hunted like African bullfrogs, hiding before pouncing on a small mammal.

It’s not clear what the frogs used the body armor for, but one possibility is that the sculptured bones may have been an adaptation to a dry environment that allowed the frogs to burrow underground, where they were less likely to bake in the hot sun, Evans said.

But the armor may also have been protection.

“There were an awful lot of things roaming around that would have liked a bite out of a big, juicy frog,” such as dinosaurs, crocodiles and even strange mammals that once lived on the Gondwana supercontinent, Evans told LiveScience.

The findings were published Jan. 28 in the journal PLOS ONE.

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New dinosaur discovery in China


This video says about itself:

New Dinosaur Discovered in China

17 Jan 2012

Archaeologists are trading high-fives this week. A new species of dinosaur has been named, 13 years after its fossilized remains were dug up in Eastern China. Named for the county where the bones were found during construction of a new highway, the skeleton puzzled researchers, who concluded it was a previously unknown species after three years of intensive study. It’s believed to be an ornithischian, or “bird-hipped” dinosaur, and would have roamed ancient China during the Cretaceous period some 100 million years ago.

The dinosaur, which was 1.5 meters long and stood less than 1 meter high, had a beak, ran on two legs, and was believed to be a herbivore. Expect thousands of little dinosaur aficionados to be playing with new toys in the next few years…as long as someone can figure out how to pronounce this dino’s name.

From the University of Pennsylvania in the USA today:

Dinosaur fossils from China help researchers describe new ‘Titan’

16 hours ago

A team led by University of Pennsylvania paleontologists has characterized a new dinosaur based on fossil remains found in northwestern China. The species, a plant-eating sauropod named Yongjinglong datangi, roamed during the Early Cretaceous period, more than 100 million years ago. This sauropod belonged to a group known as Titanosauria, members of which were among the largest living creatures to ever walk the earth.

At roughly 50-60 feet long, the Yongjinglong individual discovered was a medium-sized Titanosaur. Anatomical evidence, however, points to it being a juvenile; adults may have been larger.

The find, reported in the journal PLOS ONE, helps clarify relationships among several sauropod species that have been found in the last few decades in China and elsewhere. Its features suggest that Yongjinglong is among the most derived, or evolutionarily advanced, of the Titanosaurs yet discovered from Asia.

Doctoral student Liguo Li and professor Peter Dodson, who have affiliations in both the School of Veterinary Medicine’s Department of Animal Biology and the School of Arts and Sciences’ Department of Earth and Environmental Science, led the work. They partnered with Hailu You, a former student of Dodson’s, who now works at the Chinese Academy of Sciences’ Institute of Vertebrate Paleontology and Paleoanthropology, and Daqing Li of the Gansu Geological Museum in Lanzhou, China.

Until very recently, the United States was the epicenter for dinosaur diversity, but China surpassed the U.S. in 2007 in terms of species found. This latest discovery was made in the southeastern Lanzhou-Minhe Basin of China’s Gansu Province, about an hour’s drive from the province’s capital, Lanzhou. Two other Titanosaurs from the same period, Huanghetitan liujiaxiaensis and Daxiatitan binglingi, were discovered within the last decade in a valley one kilometer from the Yongjinglong fossils.

“As recently as 1997 only a handful of dinosaurs were known from Gansu,” Dodson said. “Now it’s one of the leading areas of China. This dinosaur is one more of the treasures of Gansu.”

During a trip to Gansu, Liguo Li was invited to study the remains, which had been in storage since being unearthed in 2008. They consisted of three teeth, eight vertebrae, the left shoulder blade, and the right radius and ulna.

The anatomical features of the bones bear some resemblance to another Titanosaur that had been discovered by paleontologists in China in 1929, named Euhelopus zdanskyi. But the team was able to identify a number of unique characteristics.

“The shoulder blade was very long, nearly 2 meters, with sides that were nearly parallel, unlike many other Titanosaurs whose scapulae bow outward,” Li said.

The scapula was so long, indeed, that it did not appear to fit in the animal’s body cavity if placed in a horizontal or vertical orientation, as is the case with other dinosaurs. Instead, Li and colleagues suggest the bone must have been oriented at an angle of 50 degrees from the horizontal.

In addition, an unfused portion of the shoulder blade indicated to the researchers that the animal under investigation was a juvenile or subadult.

“The scapula and coracoid aren’t fused here,” Li said. “It is open, leaving potential for growth.”

Thus, a full-grown adult might be larger than this 50-60 foot long individual. Future finds may help elucidate just how much larger, the researchers noted.

The ulna and radius were well preserved, enough so that the researchers could identify grooves and ridges they believe correspond with the locations of muscle attachments in the dinosaur’s leg.

The researchers were also able to draw evidence about the dinosaur’s relationship to other species from the vertebrae, one of which was from the neck and the other seven from the trunk. Notably, the vertebrae had large cavities in the interior that the team believes provided space for air sacs in the dinosaur’s body.

“These spaces are unusually large in this species,” Dodson said. “It’s believed that dinosaurs, like birds, had air sacs in their trunk, abdominal cavity and neck as a way of lightening the body.”

In addition, the longest tooth they found was nearly 15 centimeters long. Another shorter tooth contained unique characteristics, including two “buttresses,” or bony ridges, on the internal side, while Euhelopus had only one buttress on its teeth.

To gain a sense of where Yongjinglong sits on the family tree of sauropods, the researchers were able to compare its characteristics with specimens from elsewhere in China, as well as from Africa, South America and the U.S.

“We used standard paleontological techniques to compare it with phylogenies based on other specimens,” Dodson said. “It is definitely much more derived than Euhelopus and shows close similarities to derived species from South America.”

Not only does the discovery point to the fact that Titanosaurs encompass a diverse group of dinosaurs, but it also supports the growing consensus that sauropods were a dominant group in the Early Cretaceous—a view that U.S. specimens alone could not confirm.

“Based on U.S. fossils, it was once thought that sauropods dominated herbivorous dinosaur fauna during the Jurassic but became almost extinct during the Cretaceous,” Dodson said. “We now realize that, in other parts of the world, particularly in South America and Asia, sauropod dinosaurs continued to flourish in the Cretaceous, so the thought that they were minor components is no longer a tenable view.”

See also here.

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How dinosaurs originated


This video is called Brief Lecture on the Origin of Dinosaurs.

From Current Biology, Volume 24, Issue 2, R87-R95, 20 January 2014:

Summary

Dinosaurs arose in the early Triassic in the aftermath of the greatest mass extinction ever and became hugely successful in the Mesozoic. Their initial diversification is a classic example of a large-scale macroevolutionary change.

Diversifications at such deep-time scales can now be dissected, modelled and tested. New fossils suggest that dinosaurs originated early in the Middle Triassic, during the recovery of life from the devastating Permo-Triassic mass extinction. Improvements in stratigraphic dating and a new suite of morphometric and comparative evolutionary numerical methods now allow a forensic dissection of one of the greatest turnovers in the history of life. Such studies mark a move from the narrative to the analytical in macroevolutionary research, and they allow us to begin to answer the proposal of George Gaylord Simpson, to explore adaptive radiations using numerical methods.

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Dinosaur footprints discovery in India


This video is called Jurassic Park of India.

It says about itself:

15 Jan 2013

Raiyoli Dinosaur fossil park is the 3rd largest dinosaur park in the world, visitors can see the real fossils of the dinosaurs embedded in the rock as well as real dinosaurs eggs.

From the Press Trust of India:

Dinosaur footprints found near Jaisalmer

January 13, 2014 16:42 IST

Jaisalmer, Rajasthan: A team of foreign and Indian scientists have spotted the footprints of dinosaurs at Thaiat village in Jaisalmer district, sources said today.

A team of 34 foreign scientists from a number of countries including France and Germany are camping in Jaisalmer to study fossils of dinosaurs found in sandy desert areas near the city recently.

Dinosaurs‘ evolution, extinction, and paleo-bio-genography is the centre of their research related to fossils, they added.

Yesterday, the team led by Dr Jan Schlogl of Slovakia observed the footprints in one of the basal rocks of Thaiat scarp section and Professor Gregory Pienkowski of Poland identified the footprints as those of Pterosaurs or the flying dinosaur.

Pterosaurs lived in the age of dinosaurs, but were not dinosaurs themselves.

“The first footprint was small, only 5 cm long, but perfectly imprinted on the upper surface of a sandstone bed. Its shape and name is clear – it is called Grallator, a specific name given to the footprint, left by a small predatory dinosaur. The footprint maker was not bigger than an hen”, according to the sources.

However, the second foot print was much bigger – about 30 cms long. Such tridactyl footprint (three toes) is named Eurontes giganteus and it must have been left by a much bigger creature, the sources added.

Dr P K Pandey of the Geology Department at University of Rajasthan had already recorded petrosaur bore fragments during the previous years.

Near the Thaiat village on the Jaisalmer-Jodhpur highway there is an outcrop of Jurassic rocks.

Careful geological observation by the team allowed them to interpret ancient environments in which these rocks (once soft sediments) were deposited, according to Dr Pandey.

It could be imagined that a vast coastal zone of which the Jurassic sea would be encroached some 180 million years ago, he added.

These scientists have come to Rajasthan on the sidelines of the 9th International Congress on The Jurassic System, held between January 6-9th, organised by Department of Geology, University of Rajasthan in Jaipur.

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