Formation of sedimentary layers of white clay, Tamilnadu, India

Fossil site for wood fossils, Tamilnadu, India

Fossil site in Kerala, 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: A new fossil katydid of the genus Arethaea Stål (Orthoptera: Tettigoniidae) with exceptionally preserved internal organs from the Eocene Green River Formation of Colorado

July 6th, 2023 Riffin

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

A new fossil katydid of the genus Arethaea Stål (Orthoptera: Tettigoniidae) with exceptionally preserved internal organs from the Eocene Green River Formation of Colorado

A new fossil katydid of the genus Arethaea Stål (Orthoptera: Tettigoniidae) with exceptionally preserved internal organs from the Eocene Green River Formation of Colorado

50 million years ago in what is now northwestern Colorado, a katydid died, sank to the bottom of a lake and was quickly buried in fine sediments, where it remained until its compressed fossil was recovered in recent years. When researchers examined the fossil under a microscope, they saw that not only had many of the insect’s hard structures been preserved in the compressed shale, so had several internal organs and tissues, which are not normally fossilized.

They describe their findings in the journal Palaeoentomology.

“Katydids are very rare in the fossil record, so any new katydid fossil you find represents a new data point in the evolutionary history of katydids,” said palaeoentomologist and study lead Sam Heads, the director of the Prairie Research Institute’s Center for Paleontology. “But perhaps the most striking feature of this fossil is the really exceptional, remarkable preservation of internal organs — organs that you just don’t see in fossils.”

The fossil was found in the Green River Formation in Rio Blanco County, Colorado. The formation is vast, extending into three states, and is a famous fossil bed in the western U.S. because the fine-grained shales yield a very detailed record of the plants and animals that once inhabited the region, Heads said.

The katydid belongs to the genus Arethaea, a group today known as thread-legged katydids for their extremely slender, grasslike legs, Heads said. The specimen represents a new but extinct species, which Heads and his colleagues named Arethaea solterae after their colleague Leellen Solter.*

“Obviously, having a fossil species of a modern genus is really significant because it confirms the antiquity of this lineage,” Heads said. “Now we know that about 50 million years ago, this genus had already evolved and already had a morphology that mimics the grass in which it lives and hides from predators.”

The find will help scientists understand how this group of insects evolved and when they developed their unique physical structure, he said.

The rare glimpse of soft internal organs in a 50-million-year-old fossil is also remarkable, Heads said.

“Part of the digestive tract is preserved, a part of the midgut we call the ventriculus,” he said. “That’s not so unusual; we have other specimens from this location that have gut traces, so I wasn’t particularly struck by that.”

But when he looked at the specimen under a microscope, Heads saw evidence of other internal structures that he was not expecting to be preserved. There were traces of the fibers making up thoracic muscles associated with the wings or flank muscles. There was some undifferentiated tissue known as a “fat body,” an organ that aids in insect metabolism.

Even more surprisingly, “there are these little tubules that all seem to connect to a round structure — and that can only be a testis and accessory glands that are associated with the testis,” Heads said. “That’s just phenomenal. I was not expecting to see that kind of structure preserved in a rock compression. I’ve never seen that before.”

To double-check his analysis, Heads dissected several katydid specimens of the same genus to match what he was seeing in the fossil.

“They look exactly the same,” he said. “The testis, the accessory glands and the ventriculus were all the same in the present-day katydids. I was just blown away by it. To my knowledge, this is the first example of this level of preservation.”

  1. Sam W. Heads, M. Jared Thomas, Tyler J. Hedlund, Yinan Wang. A new fossil katydid of the genus Arethaea Stål (Orthoptera: Tettigoniidae) with exceptionally preserved internal organs from the Eocene Green River Formation of Colorado. Palaeoentomology, 2023; 6 (3) DOI: 10.11646/palaeoentomology.6.3.10
 <www.sciencedaily.com/releases/2023/06/230626164301.htm>.

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

 

 

WFS News: Megalodon was no cold-blooded killer

June 28th, 2023 Riffin

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

The largest marine predator that ever lived was no cold-blooded killer.

                   The largest marine predator that ever lived was no cold-blooded killer.

Well, a killer, yes. But a new analysis by environmental scientists from UCLA, UC Merced and William Paterson University sheds light on the warm-blooded animal’s ability to regulate its body temperature — and might help explain why it went extinct.

After analyzing isotopes in the tooth enamel of the ancient shark, which went extinct about 3.6 million years ago, the scientists concluded the megalodon could maintain a body temperature that was about 13 degrees Fahrenheit (about 7 degrees Celsius) warmer than the surrounding water.

That temperature difference is greater than those that have been determined for other sharks that lived alongside the megalodon and is large enough to categorize megalodons as warm-blooded.

The paper, published in Proceedings of the National Academy of Sciences, suggests that the amount of energy the megalodon used to stay warm contributed to its extinction. And it has implications for understanding current and future environmental changes.

“Studying the driving factors behind the extinction of a highly successful predatory shark like megalodon can provide insight into the vulnerability of large marine predators in modern ocean ecosystems experiencing the effects of ongoing climate change,” said lead researcher Robert Eagle, a UCLA assistant professor of atmospheric and oceanic sciences and member of the UCLA Institute of the Environment and Sustainability.

Megalodons, which are believed to have reached lengths up to 50 feet, belonged to a group of sharks called mackerel sharks — members of that group today include the great white and thresher shark. While most fish are cold-blooded, with body temperatures that are the same as the surrounding water, mackerel sharks keep the temperature of all or parts of their bodies somewhat warmer than the water around them, qualities called mesothermy and regional endothermy, respectively.

Sharks store heat generated by their muscles, making them different from fully warm-blooded or endothermic animals like mammals. In mammals, a region of the brain called the hypothalamus regulates body temperature.

Various lines of evidence have hinted that megalodon might have been mesothermic. But without data from the soft tissues that drive body temperature in modern sharks, it has been difficult to determine if or to what extent megalodon was endothermic.

In the new study, the scientists looked for answers in the megalodon’s most abundant fossil remains: its teeth. A main component of teeth is a mineral called apatite, which contains atoms of carbon and oxygen. Like all atoms, carbon and oxygen can come in “light” or “heavy” forms known as isotopes, and the amount of light or heavy isotopes that make up apatite as it forms can depend on a range of environmental factors. So the isotopic composition of fossil teeth can reveal insights about where an animal lived and the types of foods it ate, and — for marine vertebrates — information like the chemistry of the seawater where the animal lived and the animal’s body temperature.

“You can think of the isotopes preserved in the minerals that make up teeth as a kind of thermometer, but one whose reading can be preserved for millions of years,” said Randy Flores, a UCLA doctoral student and fellow of the Center for Diverse Leadership in Science, who worked on the study. “Because teeth form in the tissue of an animal when it’s alive, we can measure the isotopic composition of fossil teeth in order to estimate the temperature at which they formed and that tells us the approximate body temperature of the animal in life.”

Because most ancient and modern sharks are unable to maintain body temperatures significantly higher than the temperature of surrounding seawater, the isotopes in their teeth reflect temperatures that deviate little from the temperature of the ocean. In warm-blooded animals, however, the isotopes in their teeth record the effect of body heat produced by the animal, which is why the teeth indicate temperatures that are warmer than the surrounding seawater.

The researchers hypothesized that any difference between the isotope values of the megalodon and those of other sharks that lived at the same time would indicate the degree to which the megalodon could warm its own body.

The researchers collected teeth from the megalodon and other shark contemporaries from five locations around the world, and analyzed them using mass spectrometers at UCLA and UC Merced. Using statistical modeling to estimate sea water temperatures at each site where teeth were collected, the scientists found that megalodons’ teeth consistently yielded average temperatures that indicated it had an impressive ability to regulate body temperature.

Its warmer body allowed megalodon to move faster, tolerate colder water and spread out around the world. But it was that evolutionary advantage that might have contributed to its downfall, the researchers wrote.

The megalodon lived during the Pliocene Epoch, which began 5.33 million years ago and ended 2.58 million years ago, and global cooling during that period caused sea level and ecological changes that the megalodon did not survive.

“Maintaining an energy level that would allow for megalodon’s elevated body temperature would require a voracious appetite that may not have been sustainable in a time of changing marine ecosystem balances when it may have even had to compete against newcomers such as the great white shark,” Flores said.

Project co-leader Aradhna Tripati, a UCLA professor of Earth, planetary and space sciences and a member of the Institute of Environment and Sustainability, said the scientists now plan to apply the same approach to studying other species.

“Having established endothermy in megalodon, the question arises of how frequently it is found in apex marine predators throughout geologic history,” she said.

  1. Michael L. Griffiths, Robert A. Eagle, Sora L. Kim, Randon J. Flores, Martin A. Becker, Harry M. Maisch, Robin B. Trayler, Rachel L. Chan, Jeremy McCormack, Alliya A. Akhtar, Aradhna K. Tripati, Kenshu Shimada. Endothermic physiology of extinct megatooth sharks. Proceedings of the National Academy of Sciences, 2023; 120 (27) DOI: 10.1073/pnas.2218153120

Source: <www.sciencedaily.com/releases/2023/06/230626164144.htm>

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

WFS News: Origin and geographic evolution of cycads clarified

June 13th, 2023 Riffin

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

The African cycad Encephalartos altensteinii Lehm is widely cultivated in botanical gardens around Europe (like this one in the Botanical Garden of the University of Naples "Federico II"), including one specimen that was brought from South Africa to the UK in 1775 and that is still alive today. Large Encephalartos are highly prized as ornamental plants, and unfortunately many species have been brought to the brink of extinction by poaching. Credit: Mario Coiro

The African cycad Encephalartos altensteinii Lehm is widely cultivated in botanical gardens around Europe (like this one in the Botanical Garden of the University of Naples “Federico II”), including one specimen that was brought from South Africa to the UK in 1775 and that is still alive today. Large Encephalartos are highly prized as ornamental plants, and unfortunately many species have been brought to the brink of extinction by poaching. Credit: Mario Coiro

Paleobotanist Mario Coiro of the Institute of Paleontology at the University of Vienna and colleagues at the University of Montpellier (France) have made an important breakthrough in understanding the origin and geographic distribution of cycads. By combining genetic data with leaf morphological data from both fossil and living species for the first time, the researchers created a phylogenetic tree of these fascinating and endangered plants. The results of the study have now been published in the journal New Phytologist.

Cycads (order Cycadales) are an evolutionarily very old and once very diverse group of palm-like plants that were widespread worldwide at the time of the dinosaurs. Now their distribution is limited to subtropical regions of the Earth with low latitudes, and some of them have been considered as “living fossils.”

Until now, little was known about the origin of these plants, which are also highly valued by garden lovers and collectors, and their evolutionary distribution paths—a fact that Coiro’s team have actively challenged. To this end, they developed an innovative research approach that makes a significant contribution to clarifying the biogeographical distribution of .Modern methods and ancient plants

“We knew from fossil cycad finds that there must have been dramatic changes in their ranges during Earth’s history,” explains paleobiologist Coiro. “So we included leaf morphological data from fossil and living  in our studies and combined them with  from living cycads,” adds co-author Leyla Seyfullah.

The inclusion of the fossils in the study was of immense importance for the successful estimation of the areas of origin of the cycad ancestors and the understanding of the underlying evolutionary processes. Using a special analysis method (“Bayesian total evidence dating”), it was thus possible to create a  of the cycads, including the  finds, and to uncover important information about their origin and biogeography.

A specimen of Ctenis nilsonii (Nath.) Harris, from the Rhaetian of Scania, Sweden. This lineage of cycads lived from the Triassic to the Miocene but did not leave any extant relatives. Credit: Mario Coiro

A specimen of Ctenis nilsonii (Nath.) Harris, from the Rhaetian of Scania, Sweden. This lineage of cycads lived from the Triassic to the Miocene but did not leave any extant relatives. Credit: Mario CoiroA moving history

The study showed that cycads actually can look back on a dynamic evolutionary distribution history, with some important lineages becoming extinct and others spreading more recently. Geographically,  of both the Northern and Southern Hemispheres played a major role in the evolution of cycads. During the Carboniferous, cycads originated on the Laurasian landmass, which corresponded to the continents of today’s Northern Hemisphere. During the Jurassic, their distribution extended particularly to Gondwana, a landmass formed by the continents of today’s Southern Hemisphere. Cycads also reached their maximum latitudinal range during this time.

“We were able to demonstrate that Antarctica and Greenland, as well as land links that have already disappeared today, were crucial biogeographical nodes for the distribution of cycads,” explains Coiro. Global climatic cooling during the Neogene (15 million years ago) caused cycads to become extinct in areas of higher latitude, which explains the limitation of their current distribution to the subtropics.

The results of this study offer valuable insights into biodiversity research and also have implications for efforts to conserve recent cycads. “By understanding the historical biogeography of cycads, we gain valuable knowledge into the geographic mode of speciation and about those areas that favor speciation,” Coiro says. “Thus, our work serves as a guide for conservation strategies aimed at preserving these fascinating and endangered plants.”

Journal data: Mario Coiro et al, Reconciling fossils with phylogenies reveals the origin and macroevolutionary processes explaining the global cycad biodiversity, New Phytologist (2023). DOI: 10.1111/nph.19010

Source: Report by  University Of Vienna in Phys.org.

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

WFS News: Scientists Discover 5.5 Million-Year-Old Elephant Graveyard in Florida

June 12th, 2023 Riffin

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

Researchers and volunteers with the Florida Museum of Natural History have discovered the ancient remains of several gomphotheres at a fossil site in North Florida. Credit: Florida Museum photo by Kristen Grace

Researchers and volunteers with the Florida Museum of Natural History have discovered the ancient remains of several gomphotheres at a fossil site in North Florida. Credit: Florida Museum photo by Kristen Grace

Approximately five and a half million years ago, a number of gomphotheres, now-extinct relatives of elephants, met their end in or near a river in Northern Florida. Even though their demise probably transpired centuries apart, their remains were all deposited in a single location, entombed alongside other animals that had met with a similar fate.

Today, the river no longer exists, but the residual fossils provide a vast snapshot of life in primordial Florida to paleontologists. Early last year, researchers and volunteers commenced the excavation of these gomphotheres at the Montbrook Fossil Dig, which is expected to result in a groundbreaking discovery.

“This is a once-in-a-lifetime find,” said Jonathan Bloch, curator of vertebrate paleontology at the Florida Museum of Natural History. “It’s the most complete gomphothere skeleton from this time period in Florida and among the best in North America.”

Gomphotheres were among the most diverse proboscideans and spread to nearly every continent during their 20 million-year reign. Credit: Florida Museum illustration by Merald Clark

Gomphotheres were among the most diverse proboscideans and spread to nearly every continent during their 20 million-year reign. Credit: Florida Museum illustration by Merald Clark

Bloch and his team discovered portions of a gomphothere skeleton early in the spring of 2022. Isolated gomphothere bones have been found at Montbrook in the past, so there was no reason to suspect that this was anything out of the ordinary. But a few days later, a volunteer digging nearby discovered the articulated foot of something very large.

“I started coming upon one after another of toe and ankle bones,” said Dean Warner, a retired chemistry teacher and Montbrook volunteer. “As I continued to dig, what turned out to be the ulna and radius started to be uncovered. We all knew that something special had been found.”

Within a few days, it became clear there was not just one but several complete skeletons, including one adult and at least seven juveniles. The research team will need to fully excavate the specimens before they can accurately determine their size, but Bloch estimates the adult was eight feet tall at the shoulders. With the tusks included, the skull measures over nine feet in length.

According to Rachel Narducci, collection manager of vertebrate paleontology at the Florida Museum, it’s likely the fossils were successively deposited or transported to the area. “Modern elephants travel in herds and can be very protective of their young, but I don’t think this was a situation in which they all died at once,” she said. “It seems like members of one or multiple herds got stuck in this one spot at different times.”

Research teams have been excavating at Montbrook since 2015, when Eddie Hodge contacted Florida Museum researchers about fossils that had been discovered on his property. Since then, the site’s fine sands and compacted clays have yielded a layer cake of fossils up to nine feet deep in some places.

The fossil beds are located 30 miles inland from the Gulf of Mexico, but the area was much closer to the sea when the bones were deposited in the late Miocene, during which time temperatures and sea levels were higher than they are at present.

As a result, the remnants of camels, rhinoceroses, and llamas are encased next to both fresh and saltwater fish, turtles, alligators, and burrowing shrimp. And because the limestone the ancient river cut through was laid down when Florida was a shallow, marine platform, fossils of much older marine species, such as sharks, are also occasionally found.

Over the last seven years, paleontologists working at Montbrook have discovered the oldest deer in North America, the oldest known skull of a smilodontine sabertoothed cat and a new species of extinct heron. Fossil mainstays from the time, like bone-crushing dogs and short-faced bears, also show up scattered across the wide-brimmed fossil bed.

Despite the diversity of fossils at Montbrook, most of these animals were interred after being transported by running water, and their remains are rarely found intact. The discovery of several complete gomphotheres was entirely unexpected.

“We’ve never seen anything like this at Montbrook,” Narducci said. “Usually, we find just one part of a skeleton at this site. The gomphotheres must have been buried quickly, or they may have been caught in a curve of the river where the flow was reduced.”

Elephants and their extinct relatives are collectively called proboscideans. Before the arrival of humans, they were a common component of almost every major continent, and gomphotheres were among the most diverse. Unlike their better-known woolly mammoth counterparts — which originated and disappeared just before and after the Pleistocene ice ages — gomphotheres have an exceptionally long fossil record spanning more than 20 million years.

They first evolved in Africa in the early Miocene, roughly 23 million years ago, after which they dispersed into Europe and Asia. By 16 million years ago, they’d reached North America via the Bering land bridge, and when the Isthmus of Panama rose above the sea 2.7 million years ago, gomphotheres were waiting on the shoreline to cross into South America.

Along the way, gomphotheres evolved several unique features that allowed them to thrive in the new environments they encountered.

“We all generally know what mastodons and woolly mammoths looked like, but gomphotheres aren’t nearly as easy to categorize,” Narducci said. “They had a variety of body sizes, and the shape of their tusks differed widely between species.”

In addition to the usual pair of upper tusks common in proboscideans, some gomphotheres had a second set attached to the lower jaw, which were fashioned by natural selection into increasingly implausible configurations. Many species had small lower tusks that splayed apart or extended in parallel at the tip of a significantly elongated jaw. Tusks in the platybelodon gomphotheres were flattened and joined, resembling a massive pair of buck teeth, which they used to scrape bark from trees.

Paleontologists often use these tusks as a diagnostic feature. The gomphotheres from Montbrook have a spiral band of enamel running along the length of each tusk, giving them the appearance of a barber’s pole. Only one group of gomphotheres with this unique banding pattern existed at the time. This allowed Bloch and Narducci to narrow the identity of the Montbrook fossils to species in the genus Rhyncotherium, which were once widespread across North and Central America.

“A fossil site in southern California is the only other place in the U.S. that has produced a large sample of Rhynchotherium juveniles and adults,” Bloch said. “We’re already learning so much about the anatomy and biology of this group that we didn’t know before, including new facts about the shape of the skull and tusks.”

Gomphotheres thrived in open savannahs, which were once common in Africa, Eurasia, and the Americas. But a sustained pattern of global cooling that began about 14 million years ago led to the prominence of vast grasslands, which gradually replaced savannahs and caused gomphothere diversity to wane. Some species were able to successfully switch from tree browsing to a diet that primarily consisted of grasses, but gomphotheres were dealt another blow at the end of the Miocene, when a new group of proboscideans entered the stage.

Mammoths and elephants originated in Africa before trekking north into Eurasia, following in the footsteps of the gomphotheres that had gone before and displacing them in the process. By the time humans arrived in the Americas, there were only a few gomphothere species left, which wouldn’t last long. Faced with rapid climate change and overhunting from the continents’ newest inhabitants, the last gomphotheres disappeared at the end of the ice ages, along with the majority of other large mammal species.

The Montbrook discovery gives new life to Rhynchotherium gomphotheres and provides scientists with the opportunity to learn more about the charismatic fauna that once populated North America.

“The best part has been to share this process of discovery with so many volunteers from all over the state of Florida,” Bloch said. “Our goal is to assemble this gigantic skeleton and put it on display, taking its place alongside the iconic mammoth and mastodon already at the Florida Museum of Natural History.”

Source: Article By FLORIDA MUSEUM OF NATURAL HISTORY in  scitechdaily.com/

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

WFS News: Newly discovered dinosaur, ‘Iani,’ was face of a changing planet

June 7th, 2023 Riffin

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

A newly discovered plant-eating dinosaur may have been a species’ “last gasp” during a period when Earth’s warming climate forced massive changes to global dinosaur populations.

The specimen, named Iani smithi after Janus, the two-faced Roman god of change, was an early ornithopod, a group of dinosaurs that ultimately gave rise to the more commonly known duckbill dinosaurs such as Parasaurolophus and Edmontosaurus. Researchers recovered most of the juvenile dinosaur’s skeleton—including skull, vertebrae and limbs—from Utah’s Cedar Mountain Formation. The research is published in PLoS ONE.

Iani smithi lived in what is now Utah during the mid-Cretaceous, approximately 99 million years ago. The dinosaur’s most striking feature is its powerful jaw, with teeth designed for chewing through tough plant material.

The mid-Cretaceous was a time of big changes, which had big effects on dinosaur populations. Increased  during this time caused the Earth to warm and sea levels to rise, corralling dinosaurs on smaller and smaller landmasses. It was so warm that rainforests thrived at the poles. Flowering plant life took over  and supplanted normal food sources for herbivores.

Iani smithi. Credit: Jorge Gonzalez

In North America, giant plant-eating sauropods—once titans of the landscape—were disappearing, along with their allosaurian predators. At the same time, smaller plant eaters, like early duckbills and horned dinosaurs, and feathered theropods like tyrannosaurs and enormous oviraptorosaurs, were arriving from Asia.

Enter Iani smithi, unique not only because it’s newly discovered, but also because of its rarity in the North American fossil record and its position in dinosaur history.

Location of holotype locality for Iani smithi. (A) Global map showing location of Mussentuchit Member outcrop in central Utah, western North America, and a stratigraphic section at the quarry with dated ash horizons; and (B) graphical representation of preserved skeletal elements of the holotype specimen. Preserved elements are colored on the left facing skeletal whether they derive from the right or left side of the body. Exact positions of chevrons and ribs unknown due to poor preservation. Credit: Zanno et al., 2023, PLOS ONE, CC-BY 4.0 (creativecommons.org/licenses/by/4.0/)

Location of holotype locality for Iani smithi. (A) Global map showing location of Mussentuchit Member outcrop in central Utah, western North America, and a stratigraphic section at the quarry with dated ash horizons; and (B) graphical representation of preserved skeletal elements of the holotype specimen. Preserved elements are colored on the left facing skeletal whether they derive from the right or left side of the body. Exact positions of chevrons and ribs unknown due to poor preservation. Credit: Zanno et al., 2023, PLOS ONE, CC-BY 4.0 (creativecommons.org/licenses/by/4.0/)

“Finding Iani was a streak of luck. We knew something like it lived in this ecosystem because isolated teeth had been collected here and there, but we weren’t expecting to stumble upon such a beautiful skeleton, especially from this time in Earth’s history. Having a nearly complete skull was invaluable for piecing the story together,” says Lindsay Zanno, associate research professor at North Carolina State University, head of paleontology at the North Carolina Museum of Natural Sciences, and corresponding author of the work.

Zanno and her team used the well-preserved skeleton to analyze the evolutionary relationships of Iani and were surprised—and a bit skeptical—of the results.

“We recovered Iani as an early rhabdodontomorph, a lineage of ornithopods known almost exclusively from Europe,” Zanno says. “Recently, paleontologists proposed that another North American dinosaur, Tenontosaurus—which was as common as cattle in the Early Cretaceous—belongs to this group, as well as some Australian critters. If Iani holds up as a rhabdodontomorph, it raises a lot of cool questions.”

Key among these is, could Iani be a last gasp, a witness to the end of a once successful lineage? Zanno thinks that studying this fossil in the context of environmental and biodiversity changes during the mid-Cretaceous will give us more insight into the history of our planet.

Iani smithi is named for Janus, the two-faced god who symbolized transitions—an apt name, given its position in history.

“Iani may be the last surviving member of a lineage of dinosaurs that once thrived here in North America but were eventually supplanted by duckbill dinosaurs,” Zanno says. “Iani was alive during this transition—so this dinosaur really does symbolize a changing planet.

“This dinosaur stood on the precipice,” she says, “able to look back at the way North American ecosystems were in the past, but close enough to see the future coming like a bullet train. I think we can all relate to that.”

More information: An early-diverging iguanodontian (Dinosauria: Rhabdodontomorpha) from the Late Cretaceous of North America, PLoS ONE (2023). DOI: 10.1371/journal.pone.0286042

Courtesy: North Carolina State University

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

 

 

WFS News: Irritator challengeria two-legged, meat-eating dinosaur, a spinosaurid

June 2nd, 2023 Riffin

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

Irritator challengeri was a two-legged, meat-eating dinosaur, or more precisely—a spinosaurid. The knowledge of the species is based on the most complete fossil skull known from this group. With the aid of X-ray computed tomographs usually used in the context of medicine or material science, paleontologists from Greifswald, Munich (both Germany), Alkmaar (Netherlands) and Fribourg (Switzerland) thoroughly investigated the fossil and made astonishing discoveries.

Interpretative line drawings of the re-arranged and articulated skull of Irritator challengeri (SMNS 58022). A, right lateral view; B, sagittal cut with removed right skull half, revealing medial aspects of the left skull half. Speculatively, grey silhouettes add unknown parts to the skull known from other spinosaurids. Abbreviations: an, angular; ar, articular; boc, basioccipital; d, dentary; ep, ectopterygoid; epi, epipterygoid; f, frontal; j, jugal; l, lacrimal; ls; laterosphenoid; m, maxilla; n, nasal; osp, orbitosphenoid; oto, otoccipital; pa, palatine; par, parietal; pbsp, parabasisphenoid; pm, premaxilla; po, postorbital; pro, prootic; pra, prearticular; prf, prefrontal; pt, pterygoid; q, quadrate; qj, quadratojugal; s, stapes; sur, surangular; soc, supraoccipital; sq, squamosal; v, vomer.

Interpretative line drawings of the re-arranged and articulated skull of Irritator challengeri (SMNS 58022). A, right lateral view; B, sagittal cut with removed right skull half, revealing medial aspects of the left skull half. Speculatively, grey silhouettes add unknown parts to the skull known from other spinosaurids. Abbreviations: an, angular; ar, articular; boc, basioccipital; d, dentary; ep, ectopterygoid; epi, epipterygoid; f, frontal; j, jugal; l, lacrimal; ls; laterosphenoid; m, maxilla; n, nasal; osp, orbitosphenoid; oto, otoccipital; pa, palatine; par, parietal; pbsp, parabasisphenoid; pm, premaxilla; po, postorbital; pro, prootic; pra, prearticular; prf, prefrontal; pt, pterygoid; q, quadrate; qj, quadratojugal; s, stapes; sur, surangular; soc, supraoccipital; sq, squamosal; v, vomer.

In what is now Brazil, it is presumed that Irritator hunted relatively small prey with a strongly inclined snout that evolved to close quickly. A big surprise for the experts: when the hunter opened its muzzle, the lower jaws spread out to the sides, widening the throat region. The study was published in Palaeontologia Electronica.

Marco Schade has worked with  for several years. The creatures he investigates became extinct millions of years ago and mostly incomplete fossils are all that is left of them. The remains of extinct organisms are often housed—as in this case, in the Staatliches Museum für Naturkunde Stuttgart—in public collections and sometimes provide unexpected insights into life on our planet in times that have long since passed.

Spinosaurids are among the largest land-dwelling predators to have ever lived on Earth. Their peculiar anatomy and sparse fossil record make spinosaurids mysterious in comparison to other large-bodied carnivorous dinosaurs. Spinosaurids bear relatively long and slender snouts with numerous near-conical teeth, sturdy arms with impressive claws and very long processes on their spines.

Interpretative line drawings of the re-arranged and articulated skull of Irritator challengeri (SMNS 58022). A, anterior view; B, posterior view. Speculatively, grey silhouettes add unknown parts to the skull known from other spinosaurids. Abbreviations: an, angular; boc, basioccipital; ep, ectopterygoid; epi, epipterygoid; f, frontal; j, jugal; l, lacrimal; lsp, laterosphenoid; m, maxilla; n, nasal; oto, otoccipital; par, parietal; pbsp, parabasisphenoid; pm, premaxilla; po, postorbital; pra, prearticular; pt, pterygoid; q, quadrate; qj, quadratojugal; sur, surangular; soc, supraoccipital; sq, squamosal.

Interpretative line drawings of the re-arranged and articulated skull of Irritator challengeri (SMNS 58022). A, anterior view; B, posterior view. Speculatively, grey silhouettes add unknown parts to the skull known from other spinosaurids. Abbreviations: an, angular; boc, basioccipital; ep, ectopterygoid; epi, epipterygoid; f, frontal; j, jugal; l, lacrimal; lsp, laterosphenoid; m, maxilla; n, nasal; oto, otoccipital; par, parietal; pbsp, parabasisphenoid; pm, premaxilla; po, postorbital; pra, prearticular; pt, pterygoid; q, quadrate; qj, quadratojugal; sur, surangular; soc, supraoccipital; sq, squamosal.

The most complete fossil skull of a spinosaurid is represented by Irritator challengeri found in approx. 115 Ma old sedimentary rocks from eastern Brazil. While the species, being estimated to have reached some 6.5 m in , represents the largest animal in its ecosystem, paleontologists also found fossils from other dinosaurs, pterosaurs, relatives of crocodiles, turtles and diverse fish species there.

For their latest study, the scientists reconstructed every single skull bone of the fossil and put them together in their original position to find out what makes spinosaurids so special. With the aid of CT data, they found that Irritator probably held its snout around 45° inclined in situations that required close attention to its surroundings. This position facilitated an area of three-dimensional vision to the front, since no structures, such as the long muzzle, obstructed the field of view being produced by both eyes.

Furthermore, the skull of Irritator was evolutionarily shaped in a way that produced a relatively weak but very fast bite. Due to the shape of the lower jaw joint, when this predator opened its mouth, the lower jaws spread out to the sides, which widened the pharynx. This is somewhat similar to what is displayed by pelicans, but achieved by different biomechanical processes. These are hints for Irritator’s preference for relatively small items of prey, including fish, which were snapped up and heavily injured with speedy jaw movements in order to swiftly swallow them whole.

Verified spinosaurid fossils all come from the Early and Late Cretaceous period and encompass approx. 35 million years, which also corresponds with the length of time that separates spinosaurids from other large predatory dinosaurs in respect to their evolutionary history. The study allows new insights into the lifestyle of spinosaurids and shows that—in relation to their closer relatives—they acquired many new anatomical features in a geologically short amount of time, which eventually made them the highly specialized and exceptional dinosaurs we know today.

 

Brazil in the Early Cretaceous, 115 Ma ago: the predatory dinosaur Irritator challengeri forages with spreading lower jaws in shallow water for small prey, including fish. Credit: Olof Moleman

Brazil in the Early Cretaceous, 115 Ma ago: the predatory dinosaur Irritator challengeri forages with spreading lower jaws in shallow water for small prey, including fish. Credit: Olof Moleman

More information: Marco Schade et al, A reappraisal of the cranial and mandibular osteology of the spinosaurid Irritator challengeri (Dinosauria: Theropoda), Palaeontologia Electronica (2023). DOI: 10.26879/1242

Source: phys.org

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WFS News: What role does anoxia play in exceptional fossil preservation?

June 1st, 2023 Riffin

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All that glitters is not gold, or even fool’s gold in the case of fossils.

A recent study by scientists at The University of Texas at Austin and collaborators found that many of the fossils from Germany’s Posidonia shale do not get their gleam from pyrite, commonly known as fool’s gold, which was long thought to be the source of the shine. Instead, the golden hue is from a mix of minerals that hints at the conditions in which the fossils formed.

The discovery is important for understanding how the fossils — which are among the world’s best-preserved specimens of sea life from the Early Jurassic — came to form in the first place, and the role that oxygen in the environment had in their formation.

“When you go to the quarries, golden ammonites peek out from black shale slabs,” said study co-author Rowan Martindale, an associate professor at the UT Jackson School of Geosciences. “But surprisingly, we struggled to find pyrite in the fossils. Even the fossils that looked golden, are preserved as phosphate minerals with yellow calcite. This dramatically changes our view of this famous fossil deposit.”

The research was published in Earth Science Reviews. Drew Muscente, a former assistant professor at Cornell College and former Jackson School postdoctoral researcher, led the study.

The fossils of the Posidonia Shale date back to 183 million years ago, and include rare soft-bodied specimens such as ichthyosaur embryos, squids with ink-sacs, and lobsters. To learn more about the fossilization conditions that led to such exquisite preservation, the researchers put dozens of samples under scanning electron microscopes to study their chemical composition.

“I couldn’t wait to get them in my microscope and help tell their preservational story,” said co-author Jim Schiffbauer, an associate professor at the University of Missouri Department of Geological Sciences, who handled some of the larger samples.

The researchers found that in every instance, the fossils were primarily made up of phosphate minerals even though the surrounding black shale rock was dotted with microscopic clusters of pyrite crystals, called framboids.

“I spent days looking for the framboids on the fossil,” said co-author Sinjini Sinha, a doctoral student at the Jackson School. “For some of the specimens, I counted 800 framboids on the matrix while there was maybe three or four on the fossils.”

The fact that pyrite and phosphate are found in different places on the specimens is important because it reveals key details about the fossilization environment. Pyrite forms in anoxic (without oxygen) environments, but phosphate minerals need oxygen. The research suggests that although an anoxic seafloor sets the stage for fossilization — keeping decay and predators at bay — it took a pulse of oxygen to drive the chemical reactions needed for fossilization.

These findings complement earlier research carried out by the team on the geochemical conditions of sites known for their caches of exceptionally preserved fossils, called konservat-lagerstätten. However, the results of these studies contradict long-standing theories about the conditions needed for exceptional fossil preservation in the Posidonia.

“It’s been thought for a long time that the anoxia causes the exceptional preservation, but it doesn’t directly help,” said Sinha. “It helps with making the environment conducive to faster fossilization, which leads to the preservation, but it’s oxygenation that’s enhancing preservation.”

It turns out, the oxygenation — and the phosphate and accompanying minerals — also enhanced the fossil’s shine.

The research was funded by Cornell College and the National Science Foundation. The Posidonia fossil specimens used in this study are now part of the collections at the Jackson School’s Non-Vertebrate Paleontology Laboratory.

Journal Reference:

  1. A.D. Muscente, Olivia Vinnes, Sinjini Sinha, James D. Schiffbauer, Erin E. Maxwell, Günter Schweigert, Rowan C. Martindale. What role does anoxia play in exceptional fossil preservation? Lessons from the taphonomy of the Posidonia Shale (Germany). Earth-Science Reviews, 2023; 238: 104323 DOI: 10.1016/j.earscirev.2023.104323
University of Texas at Austin. “‘Golden’ fossils reveal origins of exceptional preservation.” ScienceDaily. ScienceDaily, 2 May 2023. <www.sciencedaily.com/releases/2023/05/230502155416.htm>.
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WFS News:107-million year-old pterosaur bones found in Australia

May 30th, 2023 Riffin

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Reconstruction of an Australian pterosaur. Researchers have verified that pterosaur bones found in Australia over 30 years ago are the oldest of their kind, dating back to 107 million years ago. Credit: Peter Trusler

Reconstruction of an Australian pterosaur. Researchers have verified that pterosaur bones found in Australia over 30 years ago are the oldest of their kind, dating back to 107 million years ago. Credit: Peter Trusler

107-million-year-old pterosaur bones, the oldest of their kind, have been confirmed by researchers in Australia, as reported in Historical Biology. The fossils, discovered over three decades ago, belonged to two distinct individuals, one of which was a juvenile — a first for Australia. The findings enhance our understanding of these creatures’ adaptation to harsh climates and raise questions about their breeding habits.

A team of researchers has confirmed that 107-million-year-old pterosaur bones discovered more than 30 years ago are the oldest of their kind ever found in Australia, providing a rare glimpse into the life of these powerful, flying reptiles that lived among the dinosaurs.

Published in the journal Historical Biology and completed in collaboration with Museums Victoria, the research analyzed a partial pelvis bone and a small wing bone discovered by a team led by Museums Victoria Research Institute’s Senior Curator of Vertebrate Palaeontology Dr. Tom Rich and Professor Pat Vickers-Rich at Dinosaur Cove in Victoria, Australia in the late 1980s.

The team found the bones belonged to two different pterosaur individuals. The partial pelvis bone belonged to a pterosaur with a wingspan exceeding two meters, and the small wing bone belonged to a juvenile pterosaur — the first ever reported in Australia.

Lead researcher and PhD student Adele Pentland, from Curtin’s School of Earth and Planetary Sciences, said pterosaurs — which were close cousins of the dinosaurs — were winged reptiles that soared through the skies during the Mesozoic Era.

“During the Cretaceous Period (145–66 million years ago), Australia was further south than it is today, and the state of Victoria was within the polar circle — covered in darkness for weeks on end during the winter. Despite these seasonally harsh conditions, it is clear that pterosaurs found a way to survive and thrive,” Ms. Pentland said.

“Pterosaurs are rare worldwide, and only a few remains have been discovered at what were high palaeolatitude locations, such as Victoria, so these bones give us a better idea as to where pterosaurs lived and how big they were.

“By analyzing these bones, we have also been able to confirm the existence of the first ever Australian juvenile pterosaur, which resided in the Victorian forests around 107 million years ago.”

Ms. Pentland said that although the bones provide important insights about pterosaurs, little is known about whether they bred in these harsh polar conditions.

“It will only be a matter of time until we are able to determine whether pterosaurs migrated north during the harsh winters to breed, or whether they adapted to polar conditions. Finding the answer to this question will help researchers better understand these mysterious flying reptiles,” Ms Pentland said.

Dr Tom Rich, from Museums Victoria Research Institute, said it was wonderful to see the fruits of research coming out of the hard work of Dinosaur Cove which was completed decades ago.

“These two fossils were the outcome of a labor-intensive effort by more than 100 volunteers over a decade,” Dr. Rich said.

“That effort involved excavating more than 60 meters of tunnel where the two fossils were found in a seaside cliff at Dinosaur Cove.”

Reference: “Oldest pterosaur remains from Australia: evidence from the Lower Cretaceous (lower Albian) Eumeralla Formation of Victoria” 30 May 2023, Historical Biology.
DOI: 10.1080/08912963.2023.2201827

The research was co-authored by researchers from Curtin’s School of Earth and Planetary Sciences, the Australian Age of Dinosaurs Museum of Natural History, Monash University, and Museums Victoria Research Institute.

Source: Article by  CURTIN UNIVERSITY in scitechdaily.com

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WFS News: The “Rosetta Stone” of Paleontology: 400 Million-Year-Old Fossil Cache Unveils Early Life

May 28th, 2023 Riffin

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A small piece of Rhynie fossil plant with fossil fungi colonizing the ends, viewed through a microscope. Credit: Loron et al.

A small piece of Rhynie fossil plant with fossil fungi colonizing the ends, viewed through a microscope. Credit: Loron et al.

Cutting-edge technology has revealed new insights about a globally famous fossil treasure trove, which may provide critical evidence concerning early life on Earth.

Scientists investigating the 400 million-year-old fossil cache, discovered in the remote northeastern region of Scotland, report that their results display a higher level of molecular preservation in these fossils than what was previously expected.

Fresh scrutiny of the exquisitely preserved treasure trove from Aberdeenshire has enabled scientists to identify the chemical fingerprints of the various organisms within it.

Just as the Rosetta Stone helped Egyptologists translate hieroglyphics, the team hopes these chemical codes can help them decipher more about the identity of the life forms, that other more ambiguous fossils represent.
The spectacular fossil ecosystem near the Aberdeenshire village of Rhynie was discovered in 1912, mineralized and encased by chert – hard rock composed of silica. Known as the Rhynie chert, it originates from the Early Devonian period – about 407 million years ago – and has a significant role to play in scientists’ understanding of life on earth.

Researchers combined the latest non-destructive imaging with data analysis and machine learning to analyze fossils from collections held by National Museums Scotland and the Universities of Aberdeen and Oxford. Scientists from the University of Edinburgh were able to probe deeper than has previously been possible, which they say could reveal new insights about less well-preserved samples.

Employing a technique known as FTIR spectroscopy – in which infrared light is used to collect high-resolution data – researchers found impressive preservation of molecular information within the cells, tissues, and organisms in the rock.

Since they already knew which organisms most of the fossils represented, the team was able to discover molecular fingerprints that reliably discriminate between fungi, bacteria, and other groups.

These fingerprints were then used to identify some of the more mysterious members of the Rhynie ecosystem, including two specimens of an enigmatic tubular “nematophyte”.

These strange organisms, which are found in Devonian – and later Silurian – sediments have both algal and fungal characteristics and were previously hard to place in either category. The new findings indicate that they were unlikely to have been either lichens or fungi.

Dr. Sean McMahon, Chancellor’s Fellow from the University of Edinburgh’s School of Physics and Astronomy and School of GeoSciences, said: “We have shown how a quick, non-invasive method can be used to discriminate between different lifeforms, and this opens a unique window on the diversity of early life on Earth.”

The team fed their data into a machine learning algorithm that was able to classify the different organisms, providing the potential for sorting other datasets from other fossil-bearing rocks.

The study, published in Nature Communications, was funded by The Royal Society, Wallonia–Brussels International, and the National Council of Science and Technology of Mexico.

Dr Corentin Loron, Royal Society Newton International Fellow from the University of Edinburgh’s School of Physics and Astronomy said the study shows the value of bridging paleontology with physics and chemistry to create new insights into early life.

“Our work highlights the unique scientific importance of some of Scotland’s spectacular natural heritage and provides us with a tool for studying life in trickier, more ambiguous remnants,” Dr. Loron said.

Dr. Nick Fraser, Keeper of Natural Sciences at National Museums Scotland, believes the value of museum collections for understanding our world should never be underestimated.

He said: “The continued development of analytical techniques provides new avenues to explore the past. Our new study provides one more way of peering ever deeper into the fossil record.”

Reference: “Molecular fingerprints resolve affinities of Rhynie chert organic fossils” by C. C. Loron, E. Rodriguez Dzul, P. J. Orr, A. V. Gromov, N. C. Fraser and S. McMahon, 13 March 2023, Nature Communications.
DOI: 10.1038/s41467-023-37047-1

Source: Article By UNIVERSITY OF EDINBURGH in Science daily.com

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WFS News: Stelladens mysteriosus: A Strange New Mosasaurid (Squamata) from the Maastrichtian (Late Cretaceous) of Morocco

May 19th, 2023 Riffin

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Scientists have discovered a new species of mosasaur, a sea-dwelling lizard from the age of the dinosaurs, with strange, ridged teeth unlike those of any known reptile. Along with other recent finds from Africa, it suggests that mosasaurs and other marine reptiles were evolving rapidly up until 66 million years ago, when they were wiped out by an asteroid along with the dinosaurs and around 90% of all species on Earth.

The new species, Stelladens mysteriosus, comes from the Late Cretaceous of Morocco and was around twice the size of a dolphin.

It had a unique tooth arrangement with blade-like ridges running down the teeth, arranged in a star-shaped pattern, reminiscent of a cross-head screwdriver.

Most mosasaurs had two bladelike, serrated ridges on the front and back of the tooth to help cut prey, however Stelladens had anywhere from four to six of these blades running down the tooth.

“It’s a surprise,” said Dr Nick Longrich from the Milner Centre for Evolution at the University of Bath, who led the study. “It’s not like any mosasaur, or any reptile, even any vertebrate we’ve seen before.”

Dr Nathalie Bardet, a marine reptile specialist from the Museum of Natural History in Paris, said: “I’ve worked on the mosasaurs of Morocco for more than 20 years, and I’d never seen anything like this before — I was both perplexed and amazed!”

That several teeth were found with the same shape suggests their strange shape was not the result of a pathology or a mutation.

The unique teeth suggest a specialised feeding strategy, or a specialised diet, but it remains unclear just what Stelladens ate.

Dr Longrich said: “We have no idea what this animal was eating, because we don’t know of anything similar either alive today, or from the fossil record.

“It’s possible it found a unique way to feed, or maybe it was filling an ecological niche that simply doesn’t exist today. The teeth look like the tip of a Phillips-head screwdriver, or maybe a hex wrench.

“So what’s it eating? Phillips head screws? IKEA furniture? Who knows.”

The teeth were small, but stout and with wear on the tips, which seemed to rule out soft-bodied prey. The teeth weren’t strong enough to crush heavily armoured animals like clams or sea urchins, however.

“That might seem to suggest it’s eating something small, and lightly armoured — thin-shelled ammonites, crustaceans, or bony fish — but it’s hard to know,” said Longrich. “There were weird animals living in the Cretaceous- ammonites, belemnites, baculites — that no longer exist. It’s possible this mosasaur ate something, and occupied a niche, that simply doesn’t exist anymore, and that might explain why nothing like this is ever seen again.

“Evolution isn’t always predictable. Sometimes it goes off in a unique direction, and something evolves that’s never been seen before, and then it never evolves again.”

The mosasaurs lived alongside dinosaurs but weren’t dinosaurs. Instead, they were giant lizards, relatives of Komodo dragons, snakes, and iguanas, adapted for a life at sea.

Mosasaurs evolved around 100 million years ago, and diversified up to 66 million years ago, when a giant asteroid hit the Yucatan Peninsula in Mexico, plunging the world into darkness.

Although scientists have debated the role of environmental changes towards the end of the Cretaceous in the extinction, Stelladens, along with recent discoveries from of Morocco, suggests that mosasaurs were evolving rapidly up to the very end — they went out at their peak, rather than fading away.

The new study shows that even after years of work in the Cretaceous of Morocco, new species are continuing to be discovered. The reason may be that most species are rare.

The authors of the study predict that in a very diverse ecosystem, it may take decades to find all of the rare species.

“We’re not even close to finding everything in these beds,” said Longrich, “This is the third new species to appear, just this year. The amount of diversity at the end of the Cretaceous is just staggering.”

Nour-Eddine Jalil, a professor at the Natural History Museum and a researcher at Univers Cadi Ayyad in Morocco, said: “The fauna has produced an incredible number of surprises — mosasaurs with teeth arranged like a saw, a turtle with a snout in the form of snorkel, a multitude of vertebrates of various shapes and sizes, and now a mosasaur with star-shaped teeth.

“We would say the works of an artist with an overflowing imagination.

“Morocco’s sites offer an unparalleled picture of the amazing biodiversity just before the great crisis of the end of the Cretaceous.”

  1. Nicholas R. Longrich, Nour-Eddine Jalil, Xabier Pereda-Suberbiola, Nathalie Bardet. Stelladens mysteriosus: A Strange New Mosasaurid (Squamata) from the Maastrichtian (Late Cretaceous) of Morocco. Fossils, 2023; 1 (1): 2 DOI: 10.3390/fossils1010002
Source: University of Bath. “Fossil of mosasaur with bizarre ‘screwdriver teeth’ found in Morocco.” ScienceDaily. ScienceDaily, 18 May 2023. <www.sciencedaily.com/releases/2023/05/230518120907.htm>.
@WFS,World Fossil Society, Athira,Riffin T Sajeev,Russel T Sajeev
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