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Formation of sedimentary layers of white clay, Tamilnadu, India

Fossil site for wood fossils, Tamilnadu, India

Fossil site in Kerala, India

Fossil wood park maintained by geological survey of India at Tamilnadu

Cretaceous fossil sites india

Fossils in rack:-Cyad

Fossils in rack:-echiniderms

Fossils in rack:-Rastellum sp

Pre-historic seabed, Cretaceous period

WFS News: Dinosaur-like archosaur Smok wawelski was crushing bones like a hyena

February 3rd, 2019

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Coprolites, or fossil droppings, of the dinosaur-like archosaur Smok wawelski contain lots of chewed-up bone fragments. This led researchers at Uppsala University to conclude that this top predator was exploiting bones for salt and marrow, a behavior often linked to mammals but seldom to archosaurs.

Sketch-drawing of the vertebrate faunal assemblage of the Lisowice site (modified from Niedźwiedzki)10. (a) Large, theropod-like predatory archosaur (Smok wawelski); (b) large temnospondyl amphibian (Cyclotosaurus sp.); (c) small predatory dinosaurs (Neotheropoda indet.); (d) temnospondyl amphibian (Gerrothorax sp.); (e) small basal crocodylomorph (Crocodylomorpha indet.); (f) small diapsid (Choristodere-like animal); (g) hybodont sharks (Polyacrodus and Hybodus); (h) coelacanth fish; (i) dipnoan fish (Ptychoceratodus sp.); (j) actinopterygian fish; (k) gigantic dicynodont; (l) dinosauriforms or early dinosaurs (Dinosauriformes indet. or Dinosauria indet.); (m) small lepidosauromorphs (Sphenodontia indet.); (n) pterosaurs (Pterosauria indet.); (o) early mammaliaform (Hallautherium sp.).

Most predatory dinosaurs used their blade-like teeth to feed on the flesh of their prey, but they are commonly not thought to be much of bone crushers. The major exception is seen in the large tyrannosaurids, such as Tyrannosaurus rex, that roamed North America toward the end of the age of dinosaurs. The tyrannosaurids are thought to have been osteophagous (voluntarily exploiting bone) based on findings of bone-rich coprolites, bite-marked bones, and their robust teeth being commonly worn.

Large to medium-sized, elongated, bone-bearing and phosphate-rich S. wawelski coprolites from Lisowice, Upper Triassic, Poland. (a) ZPAL V.33/344. (b) ZPAL V.33/342. (c) ZPAL V.33/346. (d) ZPAL V.33/604. (e) ZPAL V.33/345. (f) ZPAL V.33/600. (g) ZPAL V.33/343. (h) ZPAL V.33/340. (i) ZPAL V.33/341. (a–e,h,i) Elongated specimens. (f,g) Elongated but slightly more irregular specimens. Scale bars: 1 cm.

In a study published in Scientific Reports, researchers from Uppsala University were able to link ten large coprolites to Smok wawelski, a top predator of a Late Triassic (210 million year old) assemblage unearthed in Poland. This bipedal, 5-6 meters long animal lived some 140 million years before the tyrannosaurids of North America and had a T. rex-like appearance, although it is not fully clear whether it was a true dinosaur or a dinosaur-like precursor.

Inclusions and matrix composition of the large coprolites. (a) Specimen ZPAL V.33/340 with bone and plant fragments exposed on the surface. (b,c) SEM images of coprolite matrix with micron-sized spherical structures (b) and section of a fish scale (c) preserved in the coprolite matrix. (d–f) Virtual sections showing bone inclusions (d,e – fragments of bones; f – tooth). (g,h) EDS spectra of matrix from two coprolites displaying a calcium phosphatic composition (g – ZPAL V.33/600; h – ZPAL V.33/604). Scale bars: a – 10 mm; b – 0.2 mm; c – 1 mm; d – 10 mm; e – 3 mm; f – 2 mm.

Three of the coprolites were scanned using synchrotron microtomography. This method has just recently been applied to coprolites and works somewhat like a CT scanner in a hospital, with the difference that the energy in the x-ray beams is much stronger. This makes it possible to visualize internal structures in fossils in three dimensions.

The coprolites were shown to contain up to 50 percent of bones from prey animals such as large amphibians and juvenile dicynodonts. Several crushed serrated teeth, probably belonging to the coprolite producer itself, were also found in the coprolites. This means that the teeth were repeatedly crushed against the hard food items (and involuntarily ingested) and replaced by new ones.

Virtual reconstructions of the three scanned specimens (semi-transparent), showing the enclosed bones (white) and tooth inclusions (orange). Gross morphology and contents of coprolites ZPAL V.33/344 (a); ZPAL V.33/341 (b), and ZPAL V.33/345 (c).

Further evidence for a bone-crushing behaviour can also be found in the fossils from the same bone beds in Poland. These include worn teeth and bone-rich fossil regurgitates from Smok wawelski, as well as numerous crushed or bite-marked bones.

Several of the anatomical characters related to osteophagy, such as a massive head and robust body, seem to be shared by S. wawelski and the tyrannosaurids, despite them being distantly related and living 140 million years apart. These large predators therefore seem to provide evidence of similar feeding adaptations being independently acquired at the beginning and end of the age of dinosaurs.

Martin Qvarnström, Per E. Ahlberg, Grzegorz Niedźwiedzki. Tyrannosaurid-like osteophagy by a Triassic archosaur. Scientific Reports, 2019; 9 (1) DOI: 10.1038/s41598-018-37540-4

2. Uppsala University. “The 210-million-year-old Smok was crushing bones like a hyena.” ScienceDaily. ScienceDaily, 30 January 2019. <www.sciencedaily.com/releases/2019/01/190130161643.htm>.

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WFS News: Pterosaurs: Fur flies over feathery fossils

February 2nd, 2019

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What pterosaurs might have looked like

Two exceptionally well preserved fossils give a new picture of the pterosaurs, the flying reptiles that lived at the time of the dinosaurs.

Scientists believe the creatures may have had feathers, and looked something like brown bats with fuzzy wings.

The surprise discovery suggests feathers evolved not in birds, nor dinosaurs, but in more distant times.

Pterosaurs were the closest relatives of dinosaurs, sharing a common ancestor about 250 million years ago.

“We would suggest – tentatively – that it would be worth considering that feathers originated much earlier than we thought,” Prof Mike Benton, from the University of Bristol, told BBC News.

Hailing from China, the 160-million-year-old fossils are of two different pterosaurs, one of which is newly discovered.

Strange feathery creatures

In depth analysis shows that as well as fur – which has been suggested before – the flying reptiles had feathers like some dinosaurs, including the theropods.

“If I just saw these fluffy bits on their own, I would swear they were from a theropod dinosaur,” said Dr Steve Brusatte of the University of Edinburgh, who was not part of the study.

“This means feathers were not a bird innovation, not even a dinosaur innovation, but evolved first in a much more distant ancestor.

“The age of dinosaurs was full of all sorts of strange feathery creatures!”

BAOYU JIANG, MICHAEL BENTON ET AL./NATURE ECOLOGY Image caption Are these feathers?

BAOYU JIANG, MICHAEL BENTON ET AL./NATURE ECOLOGY
Are these feathers?

The researchers found that the pterosaurs had four different kinds of covering, including fuzzy, fur over most of their body; and, on parts of the head and wings, three types of fibres similar to modern feathers.

The fluff and feathers are likely to have been important in heat regulation and aerodynamics.

“These structures on the pterosaur make it look a bit like a fruit bat, or something like that, a fuzzy hairy creature,” said Prof Benton, who worked on the discovery with colleagues in China.

“They fly with great out-stretched bony wings that carry a substantial membrane, a bit like a bat.”

Flight in the Jurassic skies

Questions still remain over whether these are true feathers. If they are, it would suggest that feathers appeared millions of years earlier than previously thought.

Alternatively, feathers could have evolved twice during the course of evolution.

Insects were the first group to achieve the ability to fly: they developed wings at least 320 million years ago.

Pterosaurs were the first vertebrates – animals with a backbone – to evolve powered flight, about 230 million years ago.

The research is published in Nature Ecology & Evolution.

Source: Article by By Helen Briggs,BBC News

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WFS News: Antarctanax,an Iguana-sized dinosaur from Antarctica

February 1st, 2019

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Antarctica wasn’t always a frozen wasteland — 250 million years ago, it was covered in forests and rivers, and the temperature rarely dipped below freezing. It was also home to diverse wildlife, including early relatives of the dinosaurs. Scientists have just discovered the newest member of that family — an iguana-sized reptile whose name means “Antarctic king.”

A slab containing fossils of Antarctanax. Credit: Copyright Brandon Peecook, Field Museum

“This new animal was an archosaur, an early relative of crocodiles and dinosaurs,” says Brandon Peecook, a Field Museum researcher and lead author of a paper in the Journal of Vertebrate Paleontology describing the new species. “On its own, it just looks a little like a lizard, but evolutionarily, it’s one of the first members of that big group. It tells us how dinosaurs and their closest relatives evolved and spread.”

The fossil skeleton is incomplete, but paleontologists still have a good feel for the animal, named Antarctanax shackletoni (the former means “Antarctic king,” the latter is a nod to polar explorer Ernest Shackleton). Based on its similarities to other fossil animals, Peecook and his coauthors (Roger Smith of the University of Witwatersrand and the Iziko South African Museum and Christian Sidor of the Burke Museum and University of Washington) surmise that Antarctanax was a carnivore that hunted bugs, early mammal relatives, and amphibians.

The most interesting thing about Antarctanax, though, is where it lived, and when. “The more we find out about prehistoric Antarctica, the weirder it is,” says Peecook, who is also affiliated with the Burke Museum. “We thought that Antarctic animals would be similar to the ones that were living in southern Africa, since those landmasses were joined back then. But we’re finding that Antarctica’s wildlife is surprisingly unique.”

About two million years before Antarctanax lived — the blink of an eye in geologic time — Earth underwent its biggest-ever mass extinction. Climate change, caused by volcanic eruptions, killed 90% of all animal life. The years immediately after that extinction event were an evolutionary free-for-all — with the slate wiped clean by the mass extinction, new groups of animals vied to fill the gaps. The archosaurs, including dinosaurs, were one of the groups that experienced enormous growth. “Before the mass extinction, archosaurs were only found around the Equator, but after it, they were everywhere,” says Peecook. “And Antarctica had a combination of these brand-new animals and stragglers of animals that were already extinct in most places — what paleontologists call ‘dead clades walking.’ You’ve got tomorrow’s animals and yesterday’s animals, cohabiting in a cool place.”

The fact that scientists have found Antarctanax helps bolster the idea that Antarctica was a place of rapid evolution and diversification after the mass extinction. “The more different kinds of animals we find, the more we learn about the pattern of archosaurs taking over after the mass extinction,” notes Peecook.

“Antarctica is one of those places on Earth, like the bottom of the sea, where we’re still in the very early stages of exploration,” says Peecook. “Antarctanax is our little part of discovering the history of Antarctica.”

Reference:Brandon R. Peecook, Roger M. H. Smith, Christian A. Sidor. A novel archosauromorph from Antarctica and an updated review of a high-latitude vertebrate assemblage in the wake of the end-Permian mass extinction. Journal of Vertebrate Paleontology, 2019; 1 DOI: 10.1080/02724634.2018.1536664

From: www.sciencedaily.com/releases/2019/01/190131084252.htm

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WFS News: Koreamegops samsiki,The ancient spider had eyes that shone in the dark

January 31st, 2019

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The defining specimen of Koreamegops samsiki, a newfound species of spider that lived in what is now South Korea between 106 and 112 million years ago.PHOTOGRAPH BY PAUL ANTONY SELDEN

IF YOU COULD time-travel to Korea 110 million years ago, you’d see an eerie spectacle if you walked out at night with a flashlight: Each sweep of your beam would make the landscape sparkle as innumerable spider eyes glinted in the dark.

In a new study in the Journal of Systematic Paleontology, a team led by Korea Polar Research Institute paleontologist Tae-Yoon Park unveils ten fossils of tiny spiders, each less than an inch wide. The remains contain two new species and a first for paleontology: a spider’s version of night-vision goggles.

In some animals’ eyeballs, a membrane called the tapetum (tuh-PEE-tuhm) sits behind the retina and reflects light back through it. If you’ve ever seen a cat’s eyes seem to glow green at night, that’s their tapeta at work. By giving the retinas a second chance to absorb light, tapeta boost the night vision of moths, cats, owls, and many other nocturnal animals. So, too, in these ancient spiders, whose silvery tapeta still shine in the fossils.

“They’re so reflective—they clearly stick out at you,” says study coauthor Paul Selden, a paleontologist at the University of Kansas. “That was a sort of eureka moment.”

The find sheds further light on the ancient behavior of spiders, some of modern Earth’s most important predators by mass.

The eyes have it

Some of the newfound spiders belong to an extinct group known as the lagonomegopids, some of which loosely resembled today’s jumping spiders. The new fossils are the first lagonomegopids ever found in rock—all previous fossils of the group come from amber, or fossilized tree resin. (See a feathered dinosaur’s tail preserved in amber.)

Before this study, all known fossils of lagonomegopids—an extinct group of spiders—had been found in amber, including this 99-million-year-old specimen. J. dalingwateri and K. samsiki are the first lagonomegopids ever found fossilized in rock.PHOTOGRAPH BY PAUL ANTONY SELDEN

The landscape these spiders knew was very different from Korea today. Some 110 million years ago, the southern Korean peninsula was a shallow basin that formed as a nearby volcanic ridge expanded. Fish and bivalves thrived in the basin’s lakes and rivers. Dinosaurs and pterosaurs lived nearby, judging by the teeth they left behind.

After getting washed out into a lake within this basin, the spiders’ bodies ended up buried in the lake’s sediments. Minerals then replaced the spiders’ flesh: Even today, their legs show traces of the hairs that once covered them. The spiders laid undisturbed until several years ago, when collectors found them in two construction sites near the city of Jinju, one of which is now a parking lot.

Park’s team later learned that the fossils were of many different spider types, including the two new lagonomegopid species. One of the newly described spiders, Koreamegops samsiki, is named for Samsik Lee, the Korean collector who found it. The other, Jinjumegops dalingwateri, is named for British arachnologist John Dalingwater, a mentor of Selden’s who died of Parkinson’s disease in 2018.

Both new species have tapeta and enlarged secondary eyes, much like today’s wolf spiders and the prey-snaring spider Deinopis spinosa. While the fossil spiders’ eyes would have glittered as wolf spiders’ eyes do today, it’s far from a given that they hunted their prey in a similar way.

“The eyes [of K. samsiki and J. dalingwateri] are more at the corners of their head rather than the front, which is a bit of a mystery,” Selden says.

K. samsiki’s right leg preserves traces of the spider’s leg hairs.PHOTOGRAPH BY PAUL ANTONY SELDEN

Depending on how the spiders’ retinas were built, their tapeta may have made their vision blurrier, Morehouse adds. Today’s nocturnal spiders get around this issue by spacing out the light-sensitive parts of their retinas. It’s unknown whether the ancient spiders struck a similar balance—but finding more fossils would help.

“How these fossil spiders navigated such tradeoffs will probably remain unknown unless an even better set of fossils shows up,” Morehouse writes. “I’d be excited to see what future studies uncover.”

Source: Article by Michael Greshko ,National Geographic’s science desk.

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WFS News: What’s the World’s Largest Dinosaur?

January 29th, 2019

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The titanosaur dinosaur Dreadnoughtus schrani (pictured above) is the only supermassive dinosaur for which scientists have both the femur and humerus bones from the same individual. That makes it the largest dinosaur for which scientists can confidently calculate a mass. However, Argentinosaurus is likely the largest dinosaur, by mass, on record.
Credit: Jennifer Hall

The battle for the title of world’s largest dinosaur is complicated.

Here’s why: Paleontologists rarely discover an entire skeleton. They’re more likely to uncover bone fragments and then try to estimate a profile of height and weight. Moreover, there are three categories for largest dinosaur on record: the weightiest, longest and tallest.

Starting with the weightiest, the gold-medal winner is likely Argentinosaurus. This supermassive titanosaur (a titanosaur is a giant sauropod, a long-necked and long-tailed herbivorous dinosaur) that lived about 100 million to 93 million years ago, during the Cretaceous period, in what is now (you guessed it) Argentina. [What Really Killed the Dinosaurs?]

But estimates of Argentinosaurus’ weight vary widely; the beast weighed 77 tons (70 metric tons), according to London’s Natural History Museum; up to 90 tons (82 metric tons), according to New York City’s American Museum of Natural History; and 110 tons (100 metric tons), according to BBC Earth.

It’s no wonder these calculations are all over the place. Argentinosaurus is known from just 13 bones: six midback vertebrae, five fragmentary hip vertebrae, one tibia (a shinbone) and one rib fragment. “There’s a femur that you’ll see with it [in some sketches], but that femur was found 15 kilometers [9 miles] away. So, who knows who that belongs to?” said Kenneth Lacovara, a professor of paleontology and geology and the dean of the School of Earth & Environment at Rowan University in Glassboro, New Jersey.

Another contender is Patagotitan, a titanosaur that weighed a whopping 69 tons (62 metric tons) when it lived about 100 million years ago in what is now Argentina. However, this weight was calculated based on a composite of individuals (there were six found in all), rather than just one dinosaur, Lacovara noted.

Which raises the question: How do scientists calculate the weight of an extinct animal? According to Lacovara, there are three ways.

Minimum shaft circumference method: Scientists measure the minimum circumference of the humerus (the upper arm bone) and femur (the thigh bone) from the same individual. Then, they plug these numbers in to a formula. The result is highly correlative with the animal’s mass. “It makes sense,” Lacovara said, “since all quadrupeds have to put all of the weight of the body on just those four bones. [So], the structural properties of those four bones are going to correlate closely with the mass.”

There are caveats, however. If the humerus and femur bone are from different individuals, as they were with Patagotitan, “the result is an estimate of a composite individual that never actually existed,” Lacovara said. Moreover, if only a single bone (a humerus or a femur) is used, the proportions of the missing bone are a guess. “Obviously, this introduces even more uncertainty,” he said. “Examples of this are Notocolossus and Paralititan.”

The largest known dinosaur that has a humerus and femur bone from the same individual is the 77-million-year-old Dreadnoughtus, a 65-ton (59 metric tons) titanosaur that Lacovara and his team excavated in Argentina.

Volumetric method: In this approach, researchers determine the body volume of the dinosaur and use that number to calculate the animal’s weight. This is challenging, because most titanosaur skeletons are incomplete. (Dreadnoughtus is the most complete, at 70 percent. Argentinosaurus is just 3.5 percent complete.) In addition, researchers have to guess how much space the lungs and other air-filled structures took up. Experts also have to speculate how “blubbery or shrink-wrapped” the skin on these dinosaurs was.

“In my view, this method is unworkable and lacks replicability, which is one of the hallmarks of science,” Lacovara said.

Wild guesses: This is how scientists estimate the weight of dinosaurs that don’t have any preserved humerus or femur bones. “Argentinosaurus, Futalognkosaurus and Puertasaurus are examples of this,” Lacovara said. “They are clearly huge, but there is no systematic, replicable way to estimate their mass.”

Moving on, what’s the longest dinosaur? That honor likely goes to Diplodocus or Mamenchisaurus, which can be described as slender and elongated sauropod dinosaurs, Lacovara said. “Both are known from reasonably complete skeletons, and both would be about 115 feet [35 m] long.” [How Did Dinosaurs Grow So Huge?]

In contrast, the titanosaurs were shorter. For example, Dreadnoughtuswas “only” about 85 feet (26 m) long.

But this category is still rife with uncertainty. “Some dinosaurs claimed to be the longest are extremely fragmentary,” Lacovara said. “For example, Sauroposeidon is known from just four neck vertebrae. So, really, who knows?” Meanwhile, Amphicoelias, a sauropod known from only a sketch of a single vertebra in a notebook from the 19th century paleontologist Edward Cope, is sometimes cited as the longest, tallest and heaviest dinosaur.

“The vertebra was apparently lost or destroyed in transport — or maybe never existed,” Lacovara said. “You can’t have a dinosaur represented by nothing, so as far as I’m concerned, Amphicoelias is not a thing.”

As for the tallest dinosaur, the winner is likely Giraffatitan, a 40-foot-tall(12 m) sauropod dinosaur that lived in the late Jurassic about 150 million years ago in what is now Tanzania.

As for that dinosaur’s actual height, the devil is in the details.

“This, of course, depends on whether these animals could lift their necks up to maximum height,” Lacovara said. “Their forelimb and shoulder structure looks like they were angling their necks upward, but we may never know the degree to which they could do this.”

Source:Originally published on Live Science.

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WFS News: Palaeocene–Eocene Thermal Maximum prolonged by fossil carbon oxidation

January 27th, 2019

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Palaeocene–Eocene Thermal Maximum prolonged by fossil carbon oxidation

A rapid rise in temperature on ancient Earth triggered a climate response that may have prolonged the warming for many thousands of years, according to scientists.

Their study, published online in Nature Geoscience, provides new evidence of a climate feedback that could explain the long duration of the Paleocene-Eocene Thermal Maximum (PETM), which is considered the best analogue for modern climate change.

The findings also suggest that climate change today could have long-lasting impacts on global temperature even if humans are able to curb greenhouse gas emissions.

Fossiliferous core from a drilling site in Maryland.Credit: Rosie Oakes / Penn State

“We found evidence for a feedback that occurs with rapid warming that can release even more carbon dioxide into the atmosphere,” said Shelby Lyons, a doctoral student in geosciences at Penn State. “This feedback may have extended the PETM climate event for tens or hundreds of thousands of years. We hypothesize this is also something that could occur in the future.”

Increased erosion during the PETM, approximately 56 million years ago, freed large amounts of fossil carbon stored in rocks and released enough carbon dioxide, a greenhouse gas, into the atmosphere to impact temperatures long term, researchers said.

Scientists found evidence for the massive carbon release in coastal sediment fossil cores. They analyzed the samples using an innovative molecular technique that enabled them to trace how processes like erosion moved carbon in deep time.

“This technique uses molecules in a really innovative, out-of-the-box way to trace fossil carbon,” said Katherine Freeman, Evan Pugh University Professor of Geosciences at Penn State. “We haven’t really been able to do that before.”

Global temperatures increased by about 9 to 14.4 degrees Fahrenheit during the PETM, radically changing conditions on Earth. Severe storms and flooding became more common, and the warm, wet weather led to increased erosion of rocks.

As erosion wore down mountains over thousands of years, carbon was released from rocks and transported by rivers to oceans, where some was reburied in coastal sediments. Along the way, some of the carbon entered the atmosphere as greenhouse gas.

“What we found in records were signatures of carbon transport that indicated there were massive erosion regimes occurring on land,” Lyons said. “Carbon was locked on land and during the PETM it was moved and reburied. We were interested in seeing how much carbon dioxide that could release.”

Lyons was studying PETM core samples from Maryland, in a location that was once underwater, when she discovered traces of older carbon that must have once been stored in rocks on land. She initially believed the samples were contaminated, but she found similar evidence in sediments from other Mid-Atlantic sites and Tanzania.

Carbon in these samples did not share common isotope patterns of life from the PETM and appeared oily, as if it been heated over long periods of time in a different location.

“That told us what we were looking at in the records was not just material that was formed during the PETM,” Lyons said. “It was not just carbon that had been formed and deposited at that time, but likely represented something older being transported in.”

The researchers developed a mixing model to distinguish the sources of carbon. Based on the amount of older carbon in the samples, scientists were able to estimate how much carbon dioxide was released during the journey from rock to ocean sediment.

They estimated the climate feedback could have released enough carbon dioxide to explain the roughly 200,000-year duration of the PETM, something that has not been well understood.

The researchers said the findings offer a warning about modern climate change. If warming reaches certain tipping points, feedbacks can be triggered that have the potential to cause even more temperature change.

“One lesson we can learn from this research is that carbon is not stored very well on land when the climate gets wet and hot,” Freeman said. “Today, we’re pushing the system out of equilibrium and it’s not going to snap back, even when we start reducing carbon dioxide emissions.”

Shelby L. Lyons, Allison A. Baczynski, Tali L. Babila, Timothy J. Bralower, Elizabeth A. Hajek, Lee R. Kump, Ellen G. Polites, Jean M. Self-Trail, Sheila M. Trampush, Jamie R. Vornlocher, James C. Zachos, Katherine H. Freeman. Palaeocene–Eocene Thermal Maximum prolonged by fossil carbon oxidation. Nature Geoscience, 2018; 12 (1): 54 DOI: 10.1038/s41561-018-0277-3

Source: Penn State. “Ancient climate change triggered warming that lasted thousands of years.” ScienceDaily. ScienceDaily, 22 January 2019. <www.sciencedaily.com/releases/2019/01/190122104515.htm>.

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WFS News: Eretmorhipis carrolldongi,Early Triassic marine reptile

January 26th, 2019

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No animal alive today looks quite like a duckbilled platypus, but about 250 million years ago something very similar swam the shallow seas in what is now China, finding prey by touch with a cartilaginous bill. The newly discovered marine reptile Eretmorhipis carrolldongi from the lower Triassic period is described in the journal Scientific Reports Jan. 24.

Apart from its platypus-like bill, Eretmorhipis was about 70 centimeters long with a long rigid body, small head and tiny eyes, and four flippers for swimming and steering. Bony plates ran down the animal’s back.

First nearly complete specimen of the rare hupehsuchian Eretmorhipis carrolldongi (YAGM V 1401), revealing an unusually small skull. (a) photograph. (b) outlines of the bones and impressions. (c) skeletal reconstruction, with flippers from the holotype. The ruler is 5 cm long.

Eretmorhipis was previously known only from partial fossils without a head, said Professor Ryosuke Motani, a paleontologist at the University of California, Davis Department of Earth and Planetary Sciences and coauthor on the paper.

“This is a very strange animal,” Motani said. “When I started thinking about the biology I was really puzzled.”

The two new fossils show the animal’s skull had bones that would have supported a bill of cartilage. Like the modern platypus, there is a large hole in the bones in the middle of the bill. In the platypus, the bill is filled with receptors that allow it to hunt by touch in muddy streams.

In the early Triassic, the area was covered by a shallow sea, about a meter deep, over a carbonate platform extending for hundreds of miles. Eretmorhipis fossils were found at what were deeper holes, or lagoons, in the platform. There are no fossils to show what Eretmorhipis ate, but it likely fed on shrimp, worms and other small invertebrates, Motani said.

The skull and mandible of Eretmorhipis carrolldongi in two new specimens. (a) and (b) YAGM V 1401, in dorsal view. (c) and (d) WGSC V 1601, in ventral view. Scale bars are 20 mm long. Symbols: at, atlas; atns, atlantal neural spine; ax, axis; axnp, axial neural spine; bh, basihyal lingual process; ch, ceratohyal; f, frontal; j, jugal; l, lacrimal; lg, labial groove for labial cartilage; m, maxilla; mand, mandibular rami; n, nasal; os, bone resembling os paradoxum; p, parietal; palatal, unidentified palatal bones; pl, palatine; pm, premaxilla; pob, postorbital; prf, prefrontal; ps-bs, parasphenoid-basisphenoid complex; pt, pterygoid; ptf, postfrontal; q, quadrate; sq, squamosal; st, supratemporal; v, vomer.

Its long, bony body means that Eretmorhipis was probably a poor swimmer, Motani said.

“It wouldn’t survive in the modern world, but it didn’t have any rivals at the time,” he said.

Related to the dolphin-like ichthyosaurs, Eretmorhipis evolved in a world devastated by the mass extinction event at the end of the Permian era. The fossil provides more evidence of rapid evolution occurring during the early Triassic, Motani said.

Preorbito-external-narial region of Eretmorhipis carrolldongi and a bone resembling os paradoxum. (a) ‘Os paradoxum’ of WGSC V 1601, in ventral view with unfinished surface. (b) Same of YAGM V 1401, in dorsal view revealing a median ridge; (c)-(d) Preorbito-external-narial region of YAGM V 1401. Scales for (a) and (b) are 1 mm, and each square in (c) has a side length of 1 mm. See Fig. 4 for symbols.

Co-authors on the study are Long Cheng and Chun-bo Yan, Wuhan Centre of China Geological Survey, Wuhan; Da-yong Jiang, Peking University; Andrea Tintori, Università degli Studi di Milano, Italy; and Olivier Rieppel, The Field Museum, Chicago. The work was supported by grants from the China Geological Survey, the National Natural Science Foundation of China and the Ministry of Science and Technology.

Journal Reference:

Long Cheng, Ryosuke Motani, Da-yong Jiang, Chun-bo Yan, Andrea Tintori, Olivier Rieppel. Early Triassic marine reptile representing the oldest record of unusually small eyes in reptiles indicating non-visual prey detection. Scientific Reports, 2019; 9 (1) DOI: 10.1038/s41598-018-37754-6

SOURCE: University of California – Davis. “A reptile platypus from the early Triassic.” ScienceDaily. ScienceDaily, 24 January 2019. <www.sciencedaily.com/releases/2019/01/190124095055.htm>

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WFS News: T. rex fossil leads researchers to new species of shark

January 24th, 2019

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T. rex fossil leads researchers to new species of shark

Scientists examining rock left over from the discovery of a fossilized Tyrannosaurus rex recently came across a surprise: shark teeth.

The huge meat-eating dinosaur, the remains of which were extricated in the 1990s, was not killed by a shark. But, scientists said on Monday, when the 12.3-metre beast, known these days as Sue, died some 67 million years ago, it fell into a South Dakota river teeming with sharks — albeit small ones — thriving in the freshwater environment.

The skeleton of Sue, the largest, most complete and best-preserved T. rex ever unearthed, is displayed at the Field Museum in Chicago, which kept the leftover rock for years in underground storage. That rock has now yielded fossils from other creatures that were Sue’s neighbours including a shark species called Galagadon nordquistae.

Galagadon, related to a group called carpet sharks found in Indo-Pacific seas today, measured 0.3 to 0.6 metres long, with teeth the size of a sand grain, about one millimetre. Tyrannosaurus teeth were up to 30 centimetres long.

If the sharks ever interacted with Sue, it may have been when the thirsty dinosaur came to the river for a gulp of water.

“It would not surprise me at all if a T. rex individual scared a little Galagadon as it lowered its head to drink,” said North Carolina State University paleontologist Terry “Bucky” Gates, lead author of the research published in the Journal of Paleontology.

If the prehistoric shark resembled its existing relatives, it was a blunt-faced bottom-dweller with barbels by its mouth like a catfish and camouflage patterning.

Researchers hypothesize that the prehistoric shark Galagadon nordquistae was a bottom–dweller with barbels by its mouth, like a catfish, with camouflage patterning. (Velizar Simeonovski/Field Museum/Reuters)

“The teeth have an unusual shape with three unequal points and a wide apron at the root. Some of the teeth bear an uncanny resemblance to the spaceship in the 1980s arcade game Galaga, which inspired the genus name,” said co-author Pete Makovicky, a paleontologist and Field Museum dinosaur curator.

Each Galagadon tooth measures less than a millimetre across, helping researchers estimate the small size of the shark. (Terry Gates/North Carolina State University/Reuters)

Scientists also are studying fossils of at least two other shark species from Sue’s river. Virtually all sharks live in the sea, though two freshwater species today reside permanently in rivers and lakes, and some other species venture into freshwater.

“I doubt Galagadon spent its whole life in freshwater habitats,” Makovicky said, suggesting its river may have been connected to an inland sea 160 kilometres away that at the time split North America in half.

Source: CBC News.

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WFS News: World’s oldest fossil mushroom

January 20th, 2019

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CHAMPAIGN, Ill. — Roughly 115 million years ago, when the ancient supercontinent Gondwana was breaking apart, a mushroom fell into a river and began an improbable journey. Its ultimate fate as a mineralized fossil preserved in limestone in northeast Brazil makes it a scientific wonder, scientists report in the journal PLOS ONE.

The world’s oldest fossil mushroom was preserved in limestone, an extraordinarily rare event, researchers say.Photo by Jared Thomas / Drawing by Danielle Ruffatto

The mushroom somehow made its way into a highly saline lagoon, sank through the stratified layers of salty water and was covered in layer upon layer of fine sediments. In time – lots of it – the mushroom was mineralized, its tissues replaced by pyrite (fool’s gold), which later transformed into the mineral goethite, the researchers report.

The mushroom lived during the Early Cretaceous, a time of dinosaurs when the ancient supercontinent Gondwana was breaking apart.Graphic by Danielle Ruffatto

“Most mushrooms grow and are gone within a few days,” said Illinois Natural History Surveypaleontologist Sam Heads, who discovered the mushroom when digitizing a collection of fossils from the Crato Formation of Brazil. “The fact that this mushroom was preserved at all is just astonishing.

“When you think about it, the chances of this thing being here – the hurdles it had to overcome to get from where it was growing into the lagoon, be mineralized and preserved for 115 million years – have to be minuscule,” he said.

The Crato Formation mushroom fossil is the oldest ever discovered. All others have been found in amber.Graphic by Danielle Ruffatto

Before this discovery, the oldest fossil mushrooms found had been preserved in amber, said INHS mycologist Andrew Miller, a co-author of the new report. The next oldest mushroom fossils, found in amber in Southeast Asia, date to about 99 million years ago, he said.

“They were enveloped by a sticky tree resin and preserved as the resin fossilized, forming amber,” Heads said. “This is a much more likely scenario for the preservation of a mushroom, since resin falling from a tree directly onto the forest floor could readily preserve specimens. This certainly seems to have been the case, given the mushroom fossil record to date.”

The mushroom was about 5 centimeters (2 inches) tall. Electron microscopy revealed that it had gills under its cap, rather than pores or teeth, structures that release spores and that can aid in identifying species.

“Fungi evolved before land plants and are responsible for the transition of plants from an aquatic to a terrestrial environment,” Miller said. “Associations formed between the fungal hyphae and plant roots. The fungi shuttled water and nutrients to the plants, which enabled land plants to adapt to a dry, nutrient-poor soil, and the plants fed sugars to the fungi through photosynthesis. This association still exists today.”

The researchers place the mushroom in the Agaricales order and have named it Gondwanagaricites magnificus.

The INHS is a division of the Prairie Research Institute at the University of Illinois. The National Science Foundation is funding a project to digitize INHS fossil collections.

Citation:Heads SW, Miller AN, Crane JL, Thomas MJ, Ruffatto DM, Methven AS, et al. (2017) The oldest fossil mushroom. PLoS ONE 12(6): e0178327. https://doi.org/10.1371/journal.pone.0178327

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WFS News: Surface exposure dating with cosmogenic nuclides

January 19th, 2019

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Surface exposure dating with cosmogenic nuclides

SUSAN IVY-OCHS & FLORIAN KOBER

Eiszeitalter und Gegenwart Quaternary Science Journal,57/1–2,157–189,Hannover 2008

Abstract: In the last decades surface exposure dating using cosmogenic nuclides has emerged as a powerful
tool in Quaternary geochronology and landscape evolution studies. Cosmogenic nuclides are produced in
rocks and sediment due to reactions induced by cosmic rays. Landforms ranging in age from a few hundred
years to tens of millions of years can be dated (depending on rock or landform weathering rates) by measuring nuclide concentrations. In this paper the history and theory of surface exposure dating are reviewed
followed by an extensive outline of the fields of application of the method. Sampling strategies as well as
information on individual nuclides are discussed in detail. The power of cosmogenic nuclide methods lies in
the number of nuclides available (the radionuclides 10Be, 14C, 26Al, and 36Cl and the stable noble gases 3
He and 21Ne), which allows almost every mineral and hence almost every lithology to be analyzed. As a result
focus can shift to the geomorphic questions. It is important that obtained exposure ages are carefully scrutinized in the framework of detailed field studies, including local terrace or moraine stratigraphy and regional
morphostratigraphic relationships; as well as in light of independent age constraints.

Schematic diagram showing the various landforms that can be dated and approaches for using cosmogenic nuclides to address questions of timing and rates of landscape change (see also BIERMAN & NICHOLS 2004).

Summary and outlook
The ability to use cosmogenic nuclides to determine how long minerals have been exposed at the surface of the earth provides an unrivaled tool for determining ages of landforms and rates of geomorphic processes. Depending or rock and landform weathering rates, landforms ranging in age from a few hundred years to tens of millions of years can be dated. Because of this unique capability, the variety of applications of cosmogenic nuclides will continue to grow. Concern about methodological uncertainties, such as those associated with the production rates, the site latitude and
altitude scaling factors, as well as the effect of past changes in the Earth’s magnetic field, has led to the establishment of an international consortium made up of CRONUS-Earth (www.physics.purdue.edu/cronus) and CRONUS-EU (www.cronus-eu.net).

Analysis of artificial targets and samples from natural sites with independent age control are underway to refine production rates. Scaling factors are being evaluated with neutron monitors and analysis of same age natural samples taken along altitudinal transects (for example lava flows). Numerical modeling is being used to
constrain production rates and scaling factors both now and in the past. The half-lives of radioactive nuclides must be accurately known. In the case of 10Be, two different half-lives have been published, 1.51 and 1.34 Ma (GRANGER
2006; NISHIIZUMI et al. 2007). When these factors are better constrained the errors of the final ages will be closer to the range of the AMS and noble gas mass spectrometry measurement uncertainties (of the order of 1-4 %). With improved knowledge of production rates and their scaling to the site, the precision of obtained ages will improve. But the accuracy of the ages remains a question of geological uncertainties. The degradation of both rock surfaces and the landforms with time imposes clear limitations on the time range and accuracy of dating. Similarly, the natural variability of samples depends on landform morphology and its age. Obtained exposure ages must be evaluated individually for conformity with field relationships, including local terrace or moraine stratigraphy and regional morphostratigraphic relationships; as well as with independent age constraints for the same or correlative features. For older landforms (more than a hundred thousand years) measurement of mulitple cosmogenic nuclides can reveal fundamental information, such as non-continuous exposure, which must be factored into interpretations (ALVAREZ-MARRÓN et al. 2007; KOBER et al. 2007). Cosmogenic nuclides provide a powerful and multifaceted tool whose potential has yet to be fully realized. But this power is tempered with the need for careful sampling based on detailed field mapping.

Source: https://www.researchgate.net/profile/Florian_Kober/publication/236668263_Surface_exposure_dating_with_cosmogenic_nuclides/links/0c960518cc15a63b25000000/Surface-exposure-dating-with-cosmogenic-nuclides.pdf