WFS News: fossil Eusaurosphargis dalsassoi reveals lifestyle of ancient armor-plated reptile

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An exceptionally-preserved fossil from the Alps in eastern Switzerland has revealed the best look so far at an armoured reptile from the Middle Triassic named Eusaurosphargis dalsassoi. The fossil is extremely rare in that it contains the animal’s complete skeleton, giving an Anglo-Swiss research team a very clear idea of its detailed anatomy and probable lifestyle for the first time, according to a paper published in Scientific Reports today.

Eusaurosphargis dalsassoi (PIMUZ A/III 4380) in ventral view. (a) Photograph. (b) Interpretative drawing of skeleton. Abbreviations used in the figure are chevron (ch), gastralia (g), and lateral osteoderm (lo).

Eusaurosphargis dalsassoi (PIMUZ A/III 4380) in ventral view. (a) Photograph. (b) Interpretative drawing of skeleton. Abbreviations used in the figure are chevron (ch), gastralia (g), and lateral osteoderm (lo).

At just 20 cm long, the specimen represents the remains of a juvenile. Yet large portions of its body were covered in armour plates, with a distinctively spiky row around each flank, protecting the animal from predators. Today’s girdled lizards, found in Africa, have independently evolved a very similar appearance even though they are not closely related to Eusaurosphargis.

The new , found in the Prosanto Formation at Ducanfurgga, south of Davos in Switzerland, is not the first material of Eusaurosphargis to be discovered. The species was originally described in 2003 based on a partially complete and totally disarticulated specimen from Italy. This was found alongside fossils of fishes and marine reptiles, leading scientists to believe that Eusaurosphargis was an aquatic animal.

Skull and lower jaw elements of Eusaurosphargis dalsassoi (PIMUZ A/III 4380) in ventral view. (a) Photograph. White rectangle indicates section of skull shown in Fig. 5. (b,c) Virtual reconstruction of the cranial bones in ventral (b) and dorsal (c) view. Unidentified bones are shown in dark grey. Note that when possible the left (.l) and right (.r) side is indicated for the identified elements. Abbreviations used in the figure are ceratobranchial I (cbI), dentary (d), exoccipital-opisthotic (ex-op), mandible element (me), maxilla (mx), parietals (p), palatine (pa), premaxilla (pmx), pterygoid (pt), quadrate (q), squamosal (sq), and tooth (t).

Skull and lower jaw elements of Eusaurosphargis dalsassoi (PIMUZ A/III 4380) in ventral view. (a) Photograph. White rectangle indicates section of skull shown in Fig. 5. (b,c) Virtual reconstruction of the cranial bones in ventral (b) and dorsal (c) view. Unidentified bones are shown in dark grey. Note that when possible the left (.l) and right (.r) side is indicated for the identified elements. Abbreviations used in the figure are ceratobranchial I (cbI), dentary (d), exoccipital-opisthotic (ex-op), mandible element (me), maxilla (mx), parietals (p), palatine (pa), premaxilla (pmx), pterygoid (pt), quadrate (q), squamosal (sq), and tooth (t).

However, the detail preserved in the new specimen shows a skeleton without a streamlined body outline and no modification of the arms, legs or tail for swimming. This suggests that the was in fact most probably adapted to live, at least mostly, on land, even though all of its closest evolutionary relatives lived in the water.

“Until this new discovery we thought that Eusaurosphargis was aquatic, so we were astonished to discover that the skeleton actually shows adaptations to life on the land,” says Dr James Neenan, research fellow at Oxford University Museum of Natural History and co-author of the new paper about Eusaurosphargis dalsassoi. “We think this particular animal must have washed into the sea from somewhere like a beach, where it sank to the sea floor, was buried and finally fossilised.”

Zeugopodial and autopodial bones of the forelimb of Eusaurosphargis dalsassoi (PIMUZ A/III 4380). (a) Photograph. (b) Photograph overlain by interpretative drawing. Abbreviations used in the figure are entepicondyle (ent), entepicondylar foramen (entf), humerus (hu), intermedium (im), lateral osteoderm (lo), metacarpal (mc), osteoderm (o), radius (ra), ulna (ul), ulnare (uln), and digits 1 to 5 (I–V).

Zeugopodial and autopodial bones of the forelimb of Eusaurosphargis dalsassoi (PIMUZ A/III 4380). (a) Photograph. (b) Photograph overlain by interpretative drawing. Abbreviations used in the figure are entepicondyle (ent), entepicondylar foramen (entf), humerus (hu), intermedium (im), lateral osteoderm (lo), metacarpal (mc), osteoderm (o), radius (ra), ulna (ul), ulnare (uln), and digits 1 to 5 (I–V).

The findings from the research team are published in Scientific Reports as ‘A new, exceptionally preserved juvenile specimen of Eusaurosphargis dalsassoi (Diapsida) and implications for Mesozoic marine diapsid phylogeny’.

More information: ‘A new, exceptionally preserved juvenile specimen of Eusaurosphargis dalsassoi (Diapsida) and implications for Mesozoic marine diapsid phylogeny’ Scientific Reports (2017). www.nature.com/articles/s41598-017-04514-x , DOI: 10.1038/s41598-017-04514-x

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WFS News:Rapid rise of the Mesozoic sea dragons


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In the Mesozoic, the time of the dinosaurs, from 252 to 66 million years ago, marine reptiles such as ichthyosaurs and plesiosaurs were top predators in the oceans. But their origins and early rise to dominance have been somewhat mysterious.

New research published this week in the journal Paleobiology by palaeobiologists from the University of Bristol shows that they burst onto the scene, rather than expanding slowly into their ecosystems.

Lead author of the study Dr Tom Stubbs said: “We show that when marine reptiles first entered the oceans in the Triassic period, they rapidly became very diverse and had many morphological adaptations related to feeding on varied prey. Within a relatively short space of time, marine reptiles began feeding on hard-shelled invertebrates, fast-moving fish and other large marine reptiles. The range of feeding-related morphological adaptations seen in Triassic marine reptiles was never exceeded later in the Mesozoic.”

A sample of jaws from the fossil record of Mesozoic marine reptiles. The illustrated animals are (A) Pliosaurus, (B) Tylosaurus, (C) Ophthalmosaurus, and (D) Placochelys. Scale bars on the jaw illustrations represent 20cm (A-C) and 5cm (D). Credit: Dr Tom Stubbs

A sample of jaws from the fossil record of Mesozoic marine reptiles. The illustrated animals are (A) Pliosaurus, (B) Tylosaurus, (C) Ophthalmosaurus, and (D) Placochelys. Scale bars on the jaw illustrations represent 20cm (A-C) and 5cm (D).
Credit: Dr Tom Stubbs

The new research uses the rich fossil record of Mesozoic marine reptiles to statistically quantify variation in the shape and function of their jaws and teeth. Up to now, studies had been based mainly on estimates of their biodiversity, or number of species, through time. The new study explores the range of shapes and sizes, and ties characters of the shape of the jaws and teeth to modes of life, including their specialised modes of feeding.

Co-author Professor Michael Benton said: “We always knew that the marine reptiles expanded relatively fast into a world in turmoil, after a devastating mass extinction event that killed as many as 95 per cent of species. But what was unusual was that they were inventing entirely new modes of life that had not existed before the end-Permian mass extinction. Our work shows they expanded into nearly every mode of life, indicated by their feeding habits and range of body sizes, really much faster than might have been imagined.”

Intriguingly, just 30 million years after the initial marine reptile ‘evolutionary burst’, they were hit by a number of extinctions in the Late Triassic, which wiped out most groups. The new research shows that these extinctions removed many specialized niches and morphological adaptations, and had long-lasting effects on marine reptile evolution.

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  1. Thomas L. Stubbs, Michael J. Benton. Ecomorphological diversifications of Mesozoic marine reptiles: the roles of ecological opportunity and extinction. Paleobiology, 2016; 1 DOI: 10.1017/pab.2016.15

Citation:University of Bristol. “Rapid rise of the Mesozoic sea dragons.” ScienceDaily. ScienceDaily, 20 May 2016. <www.sciencedaily.com/releases/2016/05/160520101951.htm>.

Tiny fossils reveal backstory of the most mysterious amphibian alive

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Researchers have determined that the fossils of an extinct species from the Triassic Period are the long-missing link that connects Kermit the Frog’s amphibian brethren to wormlike creatures with a backbone and two rows of sharp teeth.

Named Chinlestegophis jenkinsi, the newfound fossil is the oldest relative of the most mysterious group of amphibians: caecilians. Today, these limbless, colorful serpentine carnivores live underground and range in size from 6 inches to 5 feet.

“Our textbook-changing discovery will require paleontologists to re-evaluate the timing of the origin of modern amphibian groups and how they evolved,” said Adam Huttenlocker, senior author of the study and an assistant professor in the Department of Integrative Anatomical Sciences at the Keck School of Medicine of USC.

The study, published in Proceedings of the National Academy of Sciences on June 19, expands the known history of frogs, toads and salamanders by at least 15 million years and closes a major gap in early caecilian evolution by connecting them to stereospondyls, animals with toilet-seat heads that were the most diverse amphibian group during the Triassic era more than 200 million years ago.

Chinlestegophis jenkinsi was a tiny subterranean carnivore and is an ancient relative of frogs and salamanders. Credit: Illustration by Jorge Gonzalez

Chinlestegophis jenkinsi was a tiny subterranean carnivore and is an ancient relative of frogs and salamanders.
Credit: Illustration by Jorge Gonzalez

Scientists previously believed the story of the stereospondyl order was a dead-end because, although widespread during the Triassic Period, the animals were believed to be unrelated to anything alive today. The two recently discovered fossils dispel that theory and suggest that the amphibian lineage of today evolved from a common ancestor some 315 million years ago.

“Caecilians are hard to find in the fossil record because most are so small,” Huttenlocker said. “Chinlestegophis jenkinsi still preserves a lot of the primitive morphology that is shared with other Triassic amphibians, namely their four legs.”

Before C. jenkinsi, scientists had found only two other caecilian fossils from the Age of Dinosaurs and — unlike the two recently unearthed — those came later and had reduced limbs, more closely resembling their contemporary living relatives.

“It’s possible that the things that frog and salamander tissue can do when it comes to scarless healing are also present in human DNA but may be turned off,” said Jason Pardo, lead author of the study and a doctoral candidate in the Faculty of Veterinary Medicine at the University of Calgary in Alberta, Canada. “Because humans are also vertebrates, we enhance our understanding of our own evolutionary history and genetic heritage when we gain understanding of the amphibian lineage.”

Solving mysteries in vertebrate evolution

There are currently fewer than 200 species of caecilians, which live in the wet, tropical regions of South America, Africa and Southeast Asia. But the two ancient fossil amphibians found in the late 1990s by Bryan Small, study co-author and a research associate at Texas Tech University, were preserved in the fossilized burrows of Eagle County, Colo.

The paleontologists used 3-D X-rays to reassemble the fossil remains of two C. jenkinsi specimens. Parts of a skull, spinal column, ribs, shoulder and legs survived in the fossils of the first specimen. Only the skull was distinguishable in the second specimen.

“Twenty to 30 years ago, we weren’t even sure of the origins of birds,” Pardo said. “Now we are solving some of the final remaining mysteries when it comes to what sorts of animals the major vertebrate groups evolved from. Caecilians, turtles and some fish are the only major vertebrate groups that paleontologists still have questions about.”

Characteristics of the ancient caecilian

The burrows these fossils were preserved in were almost 2 inches wide, meaning they could not have been very big. Their bullet-shaped skulls were just under 1 inch long, so the ancient caecilian was probably about the size of a small salamander, Huttenlocker said.

The length of the animal is unknown because researchers do not have the full fossil remains of the animal, but Pardo estimates that the ancient caecilian was between 6 inches to a foot long. As a small carnivore, it probably ate insects.

Its eyes would have been functional but tiny. Some of today’s caecilians do not have eyes or they are hidden under moist skin.

During the summer, this central Colorado area would have been scorching, which is probably why these subterranean animals thrived. Big dinosaurs like early relatives of the Tyrannosaurus rex and Triceratops could not have existed in such conditions, Huttenlocker said.

“The ancient caecilians lived in these burrows deep in the soil down to about the level of the water table so that they could keep wet and avoid the extreme aridity from the dry season,” Huttenlocker said. “I’m going back to Colorado this summer and hope to find more animals with more complete skeletons. We’ll find one. This is just the initial report.”

source-sciencedaily

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WFS News: A Gigantic Shark from the Lower Cretaceous Duck Creek Formation of Texas

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Citation: Frederickson JA, Schaefer SN, Doucette-Frederickson JA (2015) A Gigantic Shark from the Lower Cretaceous Duck Creek Formation of Texas. PLoS ONE 10(6): e0127162. https://doi.org/10.1371/journal.pone.0127162

Abstract:Three large lamniform shark vertebrae are described from the Lower Cretaceous of Texas. We interpret these fossils as belonging to a single individual with a calculated total body length of 6.3 m. This large individual compares favorably to another shark specimen from the roughly contemporaneous Kiowa Shale of Kansas. Neither specimen was recovered with associated teeth, making confident identification of the species impossible. However, both formations share a similar shark fauna, with Leptostyrax macrorhiza being the largest of the common lamniform sharks. Regardless of its actual identification, this new specimen provides further evidence that large-bodied lamniform sharks had evolved prior to the Late Cretaceous.

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Additional shark vertebrae found in situ in the same locality as OMNH 68860. The surrounding lithology correlates with the indurated limestone bedforms 10.5 m above the base of the measured section (photo courtesy of L. Hall, 2013).

Additional shark vertebrae found in situ in the same locality as OMNH 68860.
The surrounding lithology correlates with the indurated limestone bedforms 10.5 m above the base of the measured section (photo courtesy of L. Hall, 2013).                        

OMNH 68860 in (descending order) rostral, caudal, ventral, right lateral, dorsal, and left lateral views. https://doi.org/10.1371/journal.pone.0127162.g004

OMNH 68860 in (descending order) rostral, caudal, ventral, right lateral, dorsal, and left lateral views.
https://doi.org/10.1371/journal.pone.0127162.g004                                                

Reconstruction of the large lamniform sharks from the Duck Creek Formation and Kiowa Shale. KUVP 16343 and OMNH 68860 are both reconstructed as Leptostyrax macrorhiza and modeled after an odontaspidid. This reconstruction was based on dental similarities shared between Eoptolamnidae and Odontaspididae [14]. Both specimens represent the smallest calculated estimate based on the formula of Shimada [2]. Cretalamna appendiculata is reconstructed as a classic lamnid shark based on shared dental patterns between this genus and members of the family Lamnidae

Reconstruction of the large lamniform sharks from the Duck Creek Formation and Kiowa Shale.
KUVP 16343 and OMNH 68860 are both reconstructed as Leptostyrax macrorhiza and modeled after an odontaspidid. This reconstruction was based on dental similarities shared between Eoptolamnidae and Odontaspididae [14]. Both specimens represent the smallest calculated estimate based on the formula of Shimada [2]. Cretalamna appendiculata is reconstructed as a classic lamnid shark based on shared dental patterns between this genus and members of the family Lamnidae                                                                                                                                                                                                                                                                                                                                         @WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev        

Fossil holds new insights into how fish evolved onto land

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“It’s like a snake on the outside, but a fish on the inside.”

The fossil of an early snake-like animal — called Lethiscus stocki — has kept its evolutionary secrets for the last 340-million years.

Now, an international team of researchers, led by the University of Calgary, has revealed new insights into the ancient Scottish fossil that dramatically challenge our understanding of the early evolution of tetrapods, or four-limbed animals with backbones.

Their findings have just been published in the research journal Nature. “It forces a radical rethink of what evolution was capable of among the first tetrapods,” said project lead Jason Anderson, a paleontologist and Professor at the University of Calgary Faculty of Veterinary Medicine (UCVM).

Before this study, ancient tetrapods — the ancestors of humans and other modern-day vertebrates — were thought to have evolved very slowly from fish to animals with limbs.

“We used to think that the fin-to-limb transition was a slow evolution to becoming gradually less fish like,” he said. “But Lethiscus shows immediate, and dramatic, evolutionary experimentation. The lineage shrunk in size, and lost limbs almost immediately after they first evolved. It’s like a snake on the outside but a fish on the inside.”

University of Calgary Professor Jason Anderson, right, and doctoral student Jason Pardo published a paper in Nature about new insights into the ancient Scottish fossil called Lethiscus stocki. Credit: Photo by Riley Brandt, University of Calgary

University of Calgary Professor Jason Anderson, right, and doctoral student Jason Pardo published a paper in Nature about new insights into the ancient Scottish fossil called Lethiscus stocki.
Credit: Photo by Riley Brandt, University of Calgary

Lethicus’ secrets revealed with 3D medical imaging

Using micro-computer tomography (CT) scanners and advanced computing software, Anderson and study lead author Jason Pardo, a doctoral student supervised by Anderson, got a close look at the internal anatomy of the fossilized Lethiscus. After reconstructing CT scans its entire skull was revealed, with extraordinary results.

“The anatomy didn’t fit with our expectations,” explains Pardo. “Many body structures didn’t make sense in the context of amphibian or reptile anatomy.” But the anatomy did make sense when it was compared to early fish.

“We could see the entirety of the skull. We could see where the brain was, the inner ear cavities. It was all extremely fish-like,” explains Pardo, outlining anatomy that’s common in fish but unknown in tetrapods except in the very first. The anatomy of the paddlefish, a modern fish with many primitive features, became a model for certain aspects of Lethiscus’ anatomy.

Changing position on the tetrapod ‘family tree’

When they included this new anatomical information into an analysis of its relationship to other animals, Lethiscus moved its position on the ‘family tree’, dropping into the earliest stages of the fin-to-limb transition. “It’s a very satisfying result, having them among other animals that lived at the same time,” says Anderson.

The results match better with the sequence of evolution implied by the geologic record. “Lethiscus also has broad impacts on evolutionary biology and people doing molecular clock reproductions of modern animals,” says Anderson. “They use fossils to calibrate the molecular clock. By removing Lethiscus from the immediate ancestry of modern tetrapods, it changes the calibration date used in those analyses.”

source- sciencedaily

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WFS news: Massive vertebrae sheds new light on Alamosaurus sanjuanensis

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The discovery nearly two decades ago of nine beautifully articulated vertebrae at Big Bend National Park is shedding new light on a 66 million-year-old sauropod native to Texas and the North American southwest called Alamosaurus sanjuanensis.

Diagrammatic skeletal drawing of Alamosaurus sanjuanensis based on composite skeleton reconstruction exhibited at the Perot Museum of Nature and Science, in Dallas, Texas. Reconstruction based on BIBE 45854, TMM 41541-1, USNM 15560 and the distal caudal series of a not-yet-named South American titanosaur. Human silhouette represents a 1.8 m tall individual. Grey-filled elements indicate parts of reconstruction based upon estimates of anatomy or modifications of other taxa.

Diagrammatic skeletal drawing of Alamosaurus sanjuanensis based on composite skeleton reconstruction exhibited at the Perot Museum of Nature and Science, in Dallas, Texas. Reconstruction based on BIBE 45854, TMM 41541-1, USNM 15560 and the distal caudal series of a not-yet-named South American titanosaur. Human silhouette represents a 1.8 m tall individual. Grey-filled elements indicate parts of reconstruction based upon estimates of anatomy or modifications of other taxa.

Paleontologists from the Perot Museum of Nature and Science in Dallas have co-authored a scientific paper entitled “An articulated cervical series of Alamosaurus sanjuanensis Gilmore, 1922 (Dinosauria, Sauropoda) from Texas: new perspective on the relationships of North America’s last giant sauropod.” Their findings are now available online as an open access article at the Journal of Systematic Palaeontology website and will appear in its forthcoming January/February 2017 print edition. The lead author is Ronald S. Tykoski, Ph.D., the Perot Museum’s Director of Paleontology Lab, and the co-author is Anthony R. Fiorillo, Ph.D., the Perot Museum’s Chief Curator and Vice President of Research and Collections.

“Giant sauropods like Alamosaurus have amazed people since the 1800s. Their sheer size boggles the mind, and they have forced scientists to re-think the physical limits of land-living animals,” said Tykoski. “The fossils described in our paper reveal new details about the last sauropods in North America, which helps us better understand who Alamosaurus was related to and how this species made it to southern North America by 67 to 66 million years ago — just in time to go extinct at the end of the Cretaceous!”

The name Alamosaurus came from the Ojo Alamo trading post and geological formation in New Mexico from which the first bones of the species were found (not after the historic battle in San Antonio, Texas in 1836). The name of the trading post stemmed from the Spanish word for a huge cottonwood tree growing at the trading post. Alamosaurus was a titanosaur sauropod, one of the groups of long-necked and long-tailed dinosaurs that included the largest animals to walk the Earth.

BIBE 45854, articulated series of nine mid and posterior cervical vertebrae of a large, osteologically mature Alamosaurus sanjuanensis. Series is estimated to represent the sixth to fourteenth cervical vertebrae. A, composite photo-mosaic of the cervical series in right lateral view; identification of each vertebra indicated by C6 to C14, respectively. B, line drawing based on the photo-mosaic in A. C, line drawing in B with labels shown and vertebral fossae indicated by solid grey fill; cross-hatching represents broken bone surfaces and reconstructive material. Abbreviations: C, cervical vertebra; cdf, centrodiapophyseal fossa; clf, centrum lateral fossa; pocdf, postzygapophyseal centrodiapophyseal fossa; prcdf, prezygapophyseal centrodiapophyseal fossa; prcdf1, dorsal prezygapophyseal centrodiapophyseal fossa; prcdf2, ventral prezygapophyseal centrodiapophyseal fossa; sdf, spinodiapophyseal fossa; spof, spinopostzygapophyseal fossa; sprf, spinoprezygapophyseal fossa.

BIBE 45854, articulated series of nine mid and posterior cervical vertebrae of a large, osteologically mature Alamosaurus sanjuanensis. Series is estimated to represent the sixth to fourteenth cervical vertebrae. A, composite photo-mosaic of the cervical series in right lateral view; identification of each vertebra indicated by C6 to C14, respectively. B, line drawing based on the photo-mosaic in A. C, line drawing in B with labels shown and vertebral fossae indicated by solid grey fill; cross-hatching represents broken bone surfaces and reconstructive material. Abbreviations: C, cervical vertebra; cdf, centrodiapophyseal fossa; clf, centrum lateral fossa; pocdf, postzygapophyseal centrodiapophyseal fossa; prcdf, prezygapophyseal centrodiapophyseal fossa; prcdf1, dorsal prezygapophyseal centrodiapophyseal fossa; prcdf2, ventral prezygapophyseal centrodiapophyseal fossa; sdf, spinodiapophyseal fossa; spof, spinopostzygapophyseal fossa; sprf, spinoprezygapophyseal fossa.

The discovery of the massive bones came in 1997 when a joint field crew from the University of Texas at Dallas (UT-D) and the Perot Museum (known at that time as the Dallas Museum of Natural History) was working in the northeast section of Big Bend National Park. The scientists and volunteers were excavating a site that produced parts of several immature sauropods when Dana Biasatti, then a student at UT-D, “stretched her legs” and came upon the remarkable remains of an adult titanosaur a few hundred yards away. The team was stunned. The nine cervical (neck) vertebrae were the first articulated series of adult Alamosaurus neck bones ever found. The fossils of Alamosaurus from Big Bend National Park currently represent the biggest dinosaurs discovered in Texas.

“It was one of those days one doesn’t ever forget. The part of the animal that was exposed at the surface was the hip region. Probing around the site resulted in the discovery of this incredible neck,” said Fiorillo. “One of the intriguing aspects of this project is that for us to better understand this dinosaur in our home state, we had to also rely, in part, on the results of the scientific work the Perot Museum has been doing in Arctic Alaska over the same window of time.”

Four years later — after gaining the full cooperation and necessary permits from the National Park Service and lining up Bell Helicopter to help transport the fossils (at no cost) from the remote wilderness site — the Perot Museum and UT-D team returned to the West Texas site for their top-secret mission to recover the adult sauropod bones.

For eight mostly hot and dusty days in early May 2001, they gingerly dug out the vertebrae, then hauled almost 3,000 lbs. of plaster, wood, burlap and water on their backs to create the jackets protecting the huge bones. On the final day, the field team, along with excited members of the National Park Service and other spectators, nervously watched as the helicopter gently lifted the plaster jackets — some weighing a half of a ton or more — from the excavation site. Dangling from the chopper about 50 feet above ground, the precious cargo was slowly transported to a flatbed truck about a mile away. Once packed and safely secured, the jackets began their 550-mile journey to the Perot Museum paleo lab at Fair Park in Dallas where they’d undergo years of fossil preparation work.

“This remarkable discovery illustrates the importance of America’s public lands as places where scientists have access to perform research that benefits everyone,” said Cindy Ott-Jones, Superintendent of Big Bend National Park. “While Big Bend National Park is a place that many people enjoy for its scenery and recreational opportunities, visitors should know that a tremendous amount of scientific research is also performed in the park.”

Today, visitors can view the actual fossilized neck bones from Big Bend at the Perot Museum of Nature and Science, which opened in December 2012 near downtown Dallas. The enormous bones served as the inspiration for the centerpiece for the Museum’s T. Boone Pickens Life Then and Now Hall, a fully assembled skeleton of the Alamosaurus standing 25 feet tall and stretching more than the length of two school buses, dwarfing a Tyrannosaurus rex standing next to it. Laser digitization and 3D printing were used to create lightweight replicas of the Perot Museum’s dinosaur’s neck, along with portions of the body obtained from another skeleton at the University of Texas at Austin, and tail and leg bones in the collections of the Smithsonian Institution in Washington, D.C. A crowd favorite, the breathtaking cast was fabricated and mounted by Research Casting International of Ontario, and it remains the only rendition of a complete Alamosaurus skeleton on exhibit anywhere in the world.

Once the decision was made in 2009 to feature the Alamosaurus at the new facility, Tykoski recalls it was a three-year Herculean effort to get the vertebrae ready for the Museum’s debut. Extra staff and more than two dozen volunteers worked thousands of hours meticulously whittling away 66 million years of sediment that entombed the dinosaur bones.

Both of the Perot Museum’s paleontologists credit the success of the 19-year initiative to the numerous partners who collaborated and cooperated from start to finish.

“The paper is just the culmination of almost two decades of hard work and incredible collaboration and partnerships between so many agencies and institutions,” said Tykoski. “From people at UT-D, Big Bend National Park, Bell Helicopter, the Smithsonian Institution, the Vertebrate Paleontology Lab at UT-Austin, the dedicated staff and volunteers at the Perot Museum, and other paleontologists who offered advice and insight about these animals, so many people contributed to getting the science done and the information out there for the world to see.”

“This was such an incredible find, and we were able to work with so many people to help us reach a successful conclusion. I guess, at some level, everyone reverted back to their childhood awe of giant dinosaurs,” added Fiorillo.

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Source:Perot Museum of Nature and Science. “Massive vertebrae sheds new light on Alamosaurus sanjuanensis: Nine massive neck vertebrae discovered at Big Bend National Park.” ScienceDaily. ScienceDaily, 21 June 2016. <www.sciencedaily.com/releases/2016/06/160621111112.htm>.

World’s ‘first named dinosaur’ reveals new teeth with scanning tech!

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Pioneering technology has shed fresh light on the world’s first scientifically-described dinosaur fossil — over 200 years after it was first discovered — thanks to research by WMG at the University of Warwick and the University of Oxford’s Museum of Natural History.

Professor Mark Williams at WMG has revealed five previously unseen teeth in the jawbone of the Megalosaurus — and that historical repairs on the fossil may have been less extensive than previously thought.

 Artist's impression of how Victorian palaeontologists thought the Megalosaurus looked (R) is compared with how we now understand it to have looked (L). Credit: University of Warwick/Mark Garlick

Artist’s impression of how Victorian palaeontologists thought the Megalosaurus looked (R) is compared with how we now understand it to have looked (L).
Credit: University of Warwick/Mark Garlick

Using state of the art CT scanning technology and specialist 3D analysis software, Professor Williams took more than 3000 X-ray images of the world-famous Megalosaurus jawbone, creating a digital three-dimensional image of the fossil.

In an unprecedented level of analysis, Professor Williams at WMG was able to see inside the jawbone for the first time, tracing the roots of teeth and the extent of different repairs.

Some damage occurred to the specimen when it was removed from the rock, possibly shortly after it was discovered.

Records at the Oxford University Museum of Natural History suggest that some restoration work may have been undertaken by a museum assistant between 1927 and 1931, while repairing the specimen for display — but there are no details about the extent of the repairs or the materials used.

The scans have revealed previously unseen teeth that were growing deep within the jaw before the animal died — including the remains of old, worn teeth and also tiny newly growing teeth.

The scans also show the true extent of repairs on the fossil for the first time, revealing that there may have been at least two phases of repair, using different types of plaster. This new information will help the museum make important decisions about any future restoration work on the specimen.

This research was made possible through a collaboration between Professor Williams’ research group at WMG, University of Warwick — including PhD researcher Paul Wilson — and Professor Paul Smith, director of the Oxford University Museum of Natural History.

Professor Williams commented: “Being able to use state-of-the-art technology normally reserved for aerospace and automotive engineering to scan such a rare and iconic natural history specimen was a fantastic opportunity.

“When I was growing up I was fascinated with dinosaurs and clearly remember seeing pictures of the Megalosaurus jaw in books that I read. Having access to and scanning the real thing was an incredible experience.”

The Megalosaurus jawbone is on display at the Oxford University Museum of Natural History alongside other bones from the skeleton.

Megalosaurus — which means ‘Great Lizard’ — was a meat-eating dinosaur which lived in the Middle Jurassic, around 167 million years ago. It would have been about 9 metres long and weighed about 1.4 tonnes (1400 kg).

The research was recently presented at the Institute of Electrical and Electronics Engineers (IEEE)’s International Instrumentation and Measurement Technology Conference in Torino, Italy.

Source- Sciencedaily

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Brazilian carnivorous mammal-like reptile fossil may be new Aleodon species

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Some Late Triassic Brazilian fossils of mammal-like reptiles, previously identified as Chiniquodon, may in fact be the first Aleodon specimens found outside Africa, according to a study published June 14, 2017 in the open-access journal PLOS ONE by Agustín Martinelli from the Universidade Federal of Rio Grande do Sul, Brazil, and colleagues.

This is an artistic reconstruction and skeleton made by Voltaire Paes Neto. Credit: Voltaire Paes Neto; CC-BY

This is an artistic reconstruction and skeleton made by Voltaire Paes Neto.
Credit: Voltaire Paes Neto; CC-BY

Aleodon is a genus of probainognathian cynodont, a taxon which evolved in the Triassic period, co-existed with dinosaur precursors and other archosaurs and eventually gave rise to mammals. The Aleodon genus was first described using fossils from Tanzania and Namibia, but it was not clear if it belonged within the family of carnivorous mammal-like reptiles known as Chiniquodontids, which includes the morphologically similar Chiniquodon.

The authors of the present study examined the skulls, jaws and teeth of Middle-Late Triassic fossil specimens from the Dinodontosaurus Assemblage Zone in Rio Grande do Sul, Brazil, most of which were previously thought to be Chiniquodontids, and compared them to a known African Aleodon species, A. brachyrhamphus.

The researchers used tooth morphology to identify one of the specimens as a new Aleodon species, which they named A. cromptoni after Dr Alfred “Fuzz” Crompton, who described the Aleodon genus. They also identified as Aleodon seven Brazilian specimens, previously thought to be chiniquodontids or traversodontids, and possibly one Namibian specimen, noting that this may call the reliability of Chiniquodon identification into question. Phylogenetic analysis indicated that Aleodon cromptoni may be, as suspected, a species in the Chiniquodonidae family.

Whilst the analysis was limited by the partial nature of some of the specimens, the authors note that the identification of these Late Triassic Aleodon specimens in Brazil strengthens the correlation between probainognathians from this epoch in South America and in Africa.

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source-sciencedaily

WFS News : Corals reveals source of 1586 Sanriku, Japan tsunami

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A team of researchers, led by Dr. Rhett Butler, geophysicist at the University of Hawai’i at M?noa (UHM), re-examined historical evidence around the Pacific and discovered the origin of the tsunami that hit Sanriku, Japan in 1586 — a mega-earthquake from the Aleutian Islands that broadly impacted the north Pacific. Until now, this was considered an orphan tsunami, a historical tsunami without an obvious local earthquake source, likely originating far away.

Butler and scientists from the National Tropical Botanical Garden, UHM School of Ocean and Earth Science and Technology, and NOAA’s Pacific Tsunami Warning Center analyzed material deposited into Makauwahi Cave, Kauai during a tsunami — specifically, coral fragments that were previously dated to approximately the sixteenth century using carbon-14. Using specific isotopes of naturally-occurring thorium and uranium in the coral fragments, they determined a very precise age of the tsunami event that washed the coral ashore. Prior carbon-14 dates had an uncertainty of ±120 years, whereas the uranium-thorium date is more precise, 1572±21 years. This increased precision allowed better comparison with dated, known tsunamis and earthquakes throughout the Pacific.

“Although we were aware of the 1586 Sanriku tsunami, the age of the Kauai deposit was too uncertain to establish a link,” said Butler. “Also, the 1586 Sanriku event had been ascribed to an earthquake in Lima, Peru. After dating the corals, their more precise date matched with that of the Sanriku tsunami.”

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These are the coral fragments analyzed in this study. All pieces are small (3-5 cm in longest dimension). Specimens shown are after physical cleaning (in water). All specimens shown are corals of the genus Pocillopora, except 1C, which is Porites, and 3B, which is Montipora. Credit: R. Butler, UHM SOEST

These are the coral fragments analyzed in this study. All pieces are small (3-5 cm in longest dimension). Specimens shown are after physical cleaning (in water). All specimens shown are corals of the genus Pocillopora, except 1C, which is Porites, and 3B, which is Montipora.  Credit: R. Butler, UHM SOEST

Further, re-analysis of the Peruvian evidence showed that the 1586 Peruvian earthquake was not large enough to create a measurable tsunami hitting Japan. They found additional corroborative evidence around the Pacific which strengthened the case. Earthquakes from Cascadia, the Alaskan Kodiak region, and Kamchatka were incompatible with the Sanriku data in several ways. However, a mega-earthquake (magnitude greater than 9.25) in the Aleutians was consistent with evidence from Kauai and the northeast coast of Japan.

“Hawaii is surrounded by the ‘ring of fire’ where mega-earthquakes generate great tsunamis impacting our island shores — the 2011 Tohoku Japan is the most recent example,” said Butler. “Even though there was no seismic instrumentation in the 16th century, we offer a preponderance of evidence for the occurrence of a magnitude 9 earthquake in the Aleutian Islands. Our knowledge of past events helps us to forecast tsunami effects and thereby enable us to assess this risk for Hawaii.”

Forecast models of a great Aleutian event inform the development of new maps of extreme tsunami inundation zones for the State of Hawai’i. By linking evidence on Kauai to other sites around the Pacific, we can better understand the Aleutian earthquake that generated the tsunami.

Butler and colleagues at UHM are now working to determine how frequently great earthquakes along the Cascadia margin of the Pacific Northwest might occur. These events have the potential to devastate the coasts of Oregon and Washington, and send a dangerous tsunami to Hawai’i’s shores.

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

University of Hawaii at Manoa. “New evidence reveals source of 1586 Sanriku, Japan tsunami.” ScienceDaily. ScienceDaily, 6 June 2017. <www.sciencedaily.com/releases/2017/06/170606170332.htm>

  1. Rhett Butler, David A. Burney, Kenneth H. Rubin, David Walsh. The orphan Sanriku tsunami of 1586: new evidence from coral dating on Kaua‘i. Natural Hazards, 2017; DOI: 10.1007/s11069-017-2902-7

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

 

Geology, biology agree on Pangaea supercontinent breakup dates

@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

Scientists at The Australian National University (ANU) have found that independent estimates from geology and biology agree on the timing of the breakup of the Pangaea supercontinent into today’s continents.

When continents break up, single species are divided into two and drift apart — physically and genetically.

Lead researcher Sarah McIntyre said geologic dating of the continental drift and biological dating of the genetic drift provided independent estimates of the break-up dates over the past 180 million years.

Cartography of the world. Credit: © Rawpixel.com / Fotolia

Cartography of the world.
Credit: © Rawpixel.com / Fotolia

“This is by far the most comprehensive comparison of genetic tree-based dates and the geological dates of the continental breakups,” said Ms McIntyre, a PhD scholar at the ANU Research School of Astronomy and Astrophysics.

“After excluding species that could easily move between continents, a new comparison of these two independent dating methods, applied to the breakup of Pangaea over the past 180 million years, finds good agreement between the two methods.

“Geological dating provides important independent support for the relatively new field of using genetic trees to date biological divergences.”

The research is published in Proceedings of the Royal Society B.

“In collaboration with biologist Professor Colin Groves, we came up with a vetting procedure that excluded species that could easily migrate from one continent to another,” Ms McIntyre said.

Co-author Associate Professor Charley Lineweaver said as genetic sequence data accumulates, dates from biology are becoming increasingly robust.

“Our original goal was to quantify how long continents had been isolated from each other, to see if some species would evolve into the hypothetical ‘intelligence niche’,” said Dr Lineweaver from the Research School of Astronomy and Astrophysics and the Research School of Earth Sciences at ANU.

“Along the way, we had to verify if geological and biological dating methods agree. We found that they do.”

“This concordance between biology and geology gives phylogenetic dating more street cred,” Dr Lineweaver said.

Dr Lineweaver said the result was only the tip of the iceberg of what can be done with all the new sequence data and the divergence dates that can be extracted.

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Source-sciencedaily