WFS

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: Mbiresaurus raathi,a long-neck plant-eating dinosaur found in Zimbabwe

September 9th, 2024

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

Artistic reconstruction of Mbiresaurus raathi (in the foreground) with the rest of the Zimbabwean animal assemblage in the background. It includes two rhynchosaurs (at front right), an aetosaur (at left), and a herrerasaurid dinosaur chasing a cynodont (at back right)
ANDREY ATUCHIN/VIRGINIA TECH

An international team of paleontologists have uncovered what they believe to be the oldest dinosaur skeleton ever discovered in Africa. The skeleton of the Mbiresaurus raathi — described as a long-neck plant-eating dinosaur — was found in northern Zimbabwe, according to a news release Wednesday from Virginia Tech. The Mbiresaurus raathi lived more than 230 million years ago, researchers said.

The Mbiresaurus raathi was about 6-feet-long, had a long tail, and weighed anywhere from 20 to 65 pounds. The Mbiresaurus raathi is considered a sauropodomorph, a long-necked dinosaur.

The mostly intact skeleton was found by Virginia Tech student Christopher Griffin and other paleontologists during two digs in Zimbabwe in 2017 and 2019. The international team of researchers who found the skeleton said its only missing parts were some of the hand and portions of the skull.

“The discovery of Mbiresaurus raathi fills in a critical geographic gap in the fossil record of the oldest dinosaurs, and shows the power of hypothesis-driven fieldwork for testing predictions about the ancient past,” Griffin said in a statement.

Based off their findings, the Mbiresaurus stood on two legs and had a relatively small head with serrated triangle-shaped teeth.

“These are Africa’s oldest-known definitive dinosaurs, roughly equivalent in age to the oldest dinosaurs found anywhere in the world.” Griffin said. “The oldest known dinosaurs — from roughly 230 million years ago, the Carnian Stage of the Late Triassic period — are extremely rare and have been recovered from only a few places worldwide, mainly northern Argentina, southern Brazil and India.”

Most of the Mbiresaurus skeleton is being kept in Virginia Tech’s Derring Hall to be cleaned and studied. However, it will eventually be transferred to the Natural History Museum of Zimbabwe in Bulawayo, along with any additional fossils found in the area, the university said.

“The fact that the Mbiresaurus skeleton is almost complete makes it a perfect reference material for further finds,” Michel Zondo, a curator and fossil preparer at the museum, stated in a press release. “It is the first sauropodomorph find of its size from Zimbabwe, otherwise most of our sauropodomorph finds from here are usually of medium- to large-sized animals.”

Source: Article by Greg Cannella,https://www.cbsnews.com

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WFS News: Mysterious 50-million-year-old fish to get a new genus

September 8th, 2024

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“Pegasus” volans, MCSNV T.293. Credit: Paleontology (2024). DOI: 10.1101/2024.08.19.608581

A pair of paleontologists, one with the Museum für Naturkunde, in Germany, the other from the Università degli Studi di Torino, in Italy, has found new evidence that an ancient fish, which has defied categorization for hundreds of years, may belong to fishes in the group Teleostei. Donald Davesne and Giorgio Carnevale have published a paper describing their analysis of the only two known fossil samples of the fish on the bioRxiv preprint server.

Back in the 1700s, a fossilized fish was found in the northern part of Italy. Its appearance was so unlike any other find that it was impossible to classify. Clearly it was a new species, but what family did it come from? No one could say. Giovanni Serafino Volta, a naturalist who worked to identify other fish, classified it within the genus Pegasus, which lumped it in with seamoths.

Since that time, others in the field have pointed out that the fish fossil bears no resemblance to seamoths. Still, no one else could come up with anything better, even after another specimen was found; thus, it has held on to its genus.

In this new effort, the researchers undertook an intensive study of both fossils, hoping to establish a true classification on the tree of life.

Like others before them, the researchers noted that the ancient fish, which has been dated to approximately 50 million years ago, had a ribbon-like body. The researchers took pictures of the fossils using an ultraviolet light and observed them with a stereomicroscope. This allowed them to rule out classification within the oarfish family, one possibility suggested by others.

Artistic reconstruction of a living “Pegasus” volans feeding on bioluminescent plankton at night. Digital painting by Margaux Boetsch. Credit: bioRxiv (2024). DOI: 10.1101/2024.08.19.608581

The pair did note similarities between the fossils and cusk-eel larvae and also other fish in the Teleostei group—many have long dorsal fins similar to those of the fossilized fish. They also noted that it had an exceptionally thick abdomen, which, they note, suggested it likely had a pouch further below that held its internal organs; another finding that points to Teleostei.

On the other hand, the pair found no evidence suggesting that the fossils were larvae—instead, their large bodies and ossified skeletons suggested they were adults. But the researchers suggest that the fossils could have simply matured, and therefore still exhibited larval traits.

The researchers acknowledge that they were unable to find any firm relationship between the fossils and any other type of fish, but still insist the ancient specimens need a new genus—they plan to announce the one they have chosen for it when their paper is officially published.

Ref:Donald Davesne et al, An extraordinary larval-like teleost fish from the Eocene of Bolca, bioRxiv (2024). DOI: 10.1101/2024.08.19.608581

Source: Article by Bob Yirka , Phys.org

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WFS News:Matching dinosaur footprints found on opposite sides of the Atlantic Ocean

August 29th, 2024

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A topographic scan of the wing bones that were found broken into three pieces but still well-preserved

An international team of researchers led by SMU paleontologist Louis L. Jacobs has found matching sets of Early Cretaceous dinosaur footprints on what are now two different continents.

More than 260 footprints were discovered in Brazil and in Cameroon, showing where land-dwelling dinosaurs were last able to freely cross between South America and Africa millions of years ago before the two continents split apart.

“We determined that in terms of age, these footprints were similar,” Jacobs said. “In their geological and plate tectonic contexts, they were also similar. In terms of their shapes, they are almost identical.”

The footprints, impressed into mud and silt along ancient rivers and lakes, were found more than 3,700 miles, or 6,000 kilometers, away from each other. Dinosaurs made the tracks 120 million years ago on a single supercontinent known as Gondwana—which broke off from the larger landmass of Pangea, Jacobs said.

“One of the youngest and narrowest geological connections between Africa and South America was the elbow of northeastern Brazil nestled against what is now the coast of Cameroon along the Gulf of Guinea,” Jacobs explained. “The two continents were continuous along that narrow stretch, so that animals on either side of that connection could potentially move across it.”

Matching dinosaur footprints found on opposite sides of the Atlantic Ocean — Theropod footprint from Sousa Basin, Lower Cretaceous of northeastern Brazil. Credit: Ismar de Souza Carvalho

Most of the dinosaur fossils were created by three-toed theropod dinosaurs. A few were also likely made by sauropods or ornithischians, said Diana P. Vineyard, who is a research associate at SMU and co-author of the study.

Other co-authors of the study were Lawrence J. Flynn in the Department of Human Evolutionary Biology at Harvard University, Christopher R. Scotese in the Department of Earth and Planetary Sciences at Northwestern University and Ismar de Souza Carvalho at the Universidade Federal do Rio de Janeiro and Centro de Geociências.

The study was published by New Mexico Museum of Natural History & Science in a tribute to the late paleontologist Martin Lockley, who spent much of his career studying dinosaur tracks and footprints.

Dinosaur footprints tell the whole story

Africa and South America started to split around 140 million years ago, causing gashes in Earth’s crust called rifts to open up along pre-existing weaknesses.

As the tectonic plates beneath South America and Africa moved apart, magma from the Earth’s mantle rose to the surface, creating new oceanic crust as the continents moved away from each other. And eventually, the South Atlantic Ocean filled the void between these two newly-shaped continents.

Signs of some of those major events were evident between both locations where the dinosaur footprints were found—at the Borborema region in the northeast part of Brazil and the Koum Basin in northern Cameroon. Half-graben basins—geologic structures formed during rifting as the Earth’s crust pulls apart and faults form—are found in both areas and contain ancient river and lake sediments.

Along with dinosaur tracks, these sediments contain fossil pollen that indicate an age of 120 million years.

Before the continental connection between Africa and South America was severed, “rivers flowed and lakes formed in the basins” Jacobs said.

“Plants fed the herbivores and supported a food chain. Muddy sediments left by the rivers and lakes contain dinosaur footprints, including those of meat-eaters, documenting that these river valleys could provide specific avenues for life to travel across the continents 120 million years ago.”

Provided by Southern Methodist University

Source :PHYS.ORG

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WFS News: Gaiasia jennyae : Giant Fossil Discovery in Namibia Challenges Long-Held Evolutionary Theories

August 28th, 2024

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

Researchers have unearthed a giant basal tetrapod fossil in Namibia, revealing new aspects of early land animal evolution and highlighting the importance of southern continents in the study of these ancient species.

An international team of paleontologists has discovered a fossilized giant basal tetrapod in Namibia. Basal tetrapods, early four-legged vertebrates with fingers and toes, lived around 280 million years ago during the transition from aquatic to terrestrial life. These ancient carnivores are among the earliest ancestors of all modern animals. The nearly complete 3-meter-long skeleton, discovered in the Ugab River valley in Damaraland, belongs to a new species named Gaiasia jennyae.

This groundbreaking finding challenges the previous assumption that early tetrapods were only found in the northern hemisphere and offers new insights into the evolution of land-dwelling animals.

Unearthing a New Species

In their study, recently published in Nature, the team searched for evidence of the earliest four-legged animals to set foot on land in the ancient supercontinent Gondwana. Gondwana, which existed from about 550 to 180 million years ago, included what are now South America, Africa, Antarctica, Australia, and India.

While conducting fieldwork in Namibia, the researchers spotted something exciting. “The nearly complete skeleton was preserved in mudstone from an ancient freshwater lake. As the soft tissue decomposed, gases formed that caused calcium carbonate to crystallise around the bones, creating a hard crust that protected them from being crushed as they were buried deeper,” explains Prof. Roger Smith, Distinguished Professor at the Evolutionary Studies Institute at Wits and Emeritus Research Associate at Iziko Museums, Cape Town.

Sibusiso Mtungata, a highly skilled fossil technician from the Iziko Museum, describes the discovery moment: “We had found isolated vertebrae of something big, so we were looking for a more complete skeleton. I came across two round cylinders of rock with bone in the middle which fitted together – and then a third. I called Roger over to help me find more, and as we walked upslope, he spotted a large flat rock which he recognised as the head. When we looked along the edge and saw rows of teeth, we knew we had finally found what we had been searching for – a nearly complete skull and skeleton!”

The Significance of Gaiasia

Prof. Claudia Marsicano from the University of Buenos Aires, Argentina, elaborates on the significance of the find. “As soon as I saw this enormous animal, I knew it was a different species. There is no record of giant basal tetrapods during the Carboniferous-Permian transition (approximately 299 million years ago) anywhere in the world, and certainly none from the southern continents that made up Gondwana. What caught my attention next was the structure of the front part of the skull, which was sticking out of the ground. It showed unusually interlocking large fangs.” It was an ambush predator that ate the fish that lived in the same lake.

Collecting the fossil took some time. “The skeleton had already weathered out of the rock, so there was no need for excavation, but the whole team spent hours searching for fragments that had fallen off the skull block and moved downslope,” says Mtungata. The skeleton was then taken to the Iziko South African Museum in Cape Town to be painstakingly prepared in the Karoo Fossil Laboratory, a process that took two years. “Mechanical preparation was a challenge because it was too large to CT scan, so I didn’t know what to expect – especially in the palate where teeth of all different sizes were everywhere. And there was up to 10cm of rock around the vertebrae that needed to be drilled away, creating so much red dust that we had to bring in a special extractor,” Mtungata explains.

Analysis and Exhibition

The fossil preparation revealed that the large, flattened skull was decorated with unusual patterns and had a unique palate structure. It had enormous, backward-curved fangs in both the upper and lower jaws, making its mouth unlike anything seen before. Initially thought to be a large amphibian, further study showed that the skull had features of much older, less evolved four-legged animals, previously found only in older rocks in the northern hemisphere.

“We named the new species Gaiasia jennyae. ‘Gaiasia’ is after Gaias, a nearby desert spring where the fossil was found. ‘Jennyae’ honours Professor Jennifer Clack, a world-renowned expert in early tetrapod evolution, who passed away in 2020,” explains Smith.

The new findings strongly suggest that early tetrapods were well-established in the cold-temperate regions of Gondwana as early as the Carboniferous-Permian transition. “This discovery challenges previous beliefs about early tetrapod distribution and evolution, which were mostly based on fossils from the northern hemisphere,” says Marsicano. “Our research shows a well-established early Permian fauna, with Gaiasia as an apex predator, in rocks from high-latitude Gondwana, now located in central Namibia. This challenges previous ideas and proves that the early history of tetrapods in Pangea during the Palaeozoic was much more complex than we thought.”

The specimen has been returned to Windhoek, where it will soon be on display in the Geological Museum of Namibia.

Reference: “Giant stem tetrapod was apex predator in Gondwanan late Palaeozoic ice age” by Claudia A. Marsicano, Jason D. Pardo, Roger M. H. Smith, Adriana C. Mancuso, Leandro C. Gaetano and Helke Mocke, 3 July 2024, Nature.
DOI: 10.1038/s41586-024-07572-0

Source: Article by BY UNIVERSITY OF THE WITWATERSRAND@Scitechdaily.

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WFS News: Giant Fossil Beans Unlock Secrets of Ancient Rainforests

August 25th, 2024

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

Scans of a giant fossil legume revealed the extinct species is a relative of the modern black bean tree. Credit: Edward Spagnuolo

Ancient fossil beans the size of modern limes may provide new insight into the evolution of today’s diverse Southeast Asian and Australian rainforests, according to Penn State researchers who identified the plants.

The researchers determined that the fossils, which are among the largest seeds in the fossil record, represent a now-extinct legume genus that lived in Southeast Asia and was closely related to modern Castanospermum, known as the black bean tree. This tree is only found today in the coastal rainforests of northern Australia and neighboring islands.

The study, conducted in collaboration with paleontologists from Indonesia, Canada, the United Kingdom, and elsewhere in the United States, was recently published in the International Journal of Plant Sciences.

Insights from Eocene-Era Fossils

The fossils, discovered in Indonesian Borneo, date back to the Eocene period approximately 34 to 40 million years ago. They suggest that the ancestors of the black bean tree migrated from Asia into Australia during the tectonic-plate collision that brought the land masses together and allowed for an exchange of plants and animals between the continents. The collision of the Southeast Asian and Australian tectonic plates, which began about 20 million years ago and continues today, led to a large exchange of plant and animal species between the landmasses, the scientists said.

Giant bean fossils of the newly described extinct legume Jantungspermum gunnellii were found in Indonesian Borneo. The legumes were closely related to the Australian back bean tree, Castanospermum, found today only in lowland rainforests of northern Australia and neighboring islands. Credit: Edward Spagnuolo

The findings provide the first macrofossil evidence of a plant lineage moving from Asia into Australia after the Asia-Australia tectonic collision, the researchers said. The fossils are also the oldest definite fossil legumes — the bean family — from the Malay Archipelago and the first fossil record anywhere of plants related to the black bean tree.

“These fossil seeds suggest that the ancient relatives of Castanospermum migrated into Australia from Southeast Asia during the tectonic collision event and later went extinct in Asia,” said Edward Spagnuolo, a doctoral student in the Department of Geosciences at Penn State and lead author of the study.

Overcoming Challenges in Fossil Collection

These findings challenge most of the existing direct macrofossil evidence for plant migrations, which represents lineages that moved from Australia into Asia. According to the scientists, the lack of direct evidence for movement from Asia to Australia is at least partially due to a poor plant fossil record in the Malay Archipelago, which includes the Philippines, Indonesia, East Timor, Papua New Guinea, and parts of Malaysia.

“It’s really hard to collect fossils in this part of the world,” Spagnuolo said. “Most surface rocks are destroyed by the heavy tropical rainfall or covered by vegetation, agriculture and buildings, so there are few places to look for fossils other than mine and quarry exposures. There is also very little paleontological infrastructure. We’re fortunate to have a partnership with Indonesian paleontologists at Institut Teknologi Bandung in Java, who make this work possible.”

Field Discoveries and Fossil Analysis

An international research team, including Peter Wilf, professor of geosciences at Penn State, collected the fossils in 2014 from the seams of a coal mine in South Kalimantan, Indonesian Borneo. The collection included three large beans, pollen samples, and about 40 leaves. Along with plants, the team also discovered diverse fossilized bird tracks, burrowing traces of marine invertebrates and fossil turtle remains, among other fossils recently published or under continued study.

The seeds are some of the largest in the fossil record, excluding coconuts and some other palms. They would have grown in a pod that most likely reached up to 3 feet long, or the length of a baseball bat, and fit up to five seeds, the scientists said.

After fieldwork, the fossils were loaned to Penn State, where the seeds underwent CT scan imaging. Spagnuolo and Wilf analyzed the fossil beans taxonomically, describing anatomical characters useful for identification, and found they most closely resembled modern Castanospermum, which has no previous fossil representatives.

“Although some of the characteristics of these fossils are common across legumes, there is no fossil or living legume group besides Castanospermum that has a combination of features closely matching the fossils,” Spagnuolo said. “That makes us confident with our identification.”

The fossil seeds were named Jantungspermum gunnellii. The genus name refers to the heart shape of the fossil — jantung means heart in Indonesian and spermum means seed in Latin. The species name honors the late Gregg Gunnell, a vertebrate paleontologist formerly of the Duke University Lemur Center, who led the field trip.

Legumes are a diverse family of flowering plants, with about 20,000 species alive today that include many large tropical trees, the scientists said. But despite their abundance and diversity in modern ecosystems, these seeds are the only definite legume fossils from before the Neogene period, the interval between 2.6 million and 23 million years ago, in the Southeast Asian wet tropics.

“The tropics are the most diverse biome on Earth,” Wilf said. “We know very little from the fossil record about how tropical ecosystems evolved, especially in Asia, even as extinction risks are rising quickly, and we lose vast areas every year to deforestation. The Penn State paleobotany group is working on this problem in the field with colleagues in several Asian countries, and the new giant fossil beans from Borneo are a fantastic example of the discovery potential.”

These findings confirm legumes’ presence in Southeast Asia and fill a critical hole in the fossil record, the scientists said.

“We have a great legume fossil record for much of the world but not Southeast Asia,” Spagnuolo said. “Our work highlights the neglected paleobotanical potential of this region and the need for more fossil sampling in the Malay Archipelago.”

Reference: “Giant Seeds of an Extant Australasian Legume Lineage Discovered in Eocene Borneo (South Kalimantan, Indonesia)” by Edward J. Spagnuolo, Peter Wilf, John-Paul Zonneveld, David Shaw, Aswan, Yan Rizal, Yahdi Zaim, Jonathan I. Bloch and Russell L. Ciochon, 25 July 2024,

Source : Article By MATTHEW CARROLL, PENN STATE in https://scitechdaily.com

WFS News:A new theropod dinosaur from the Callovian Balabansai Formation of Kyrgyzstan

August 24th, 2024

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

Theropod dinosaurs are one of the most important large groups of dinosaurs, including well-known predators, such as Tyrannosaurus and Allosaurus, as well as modern birds. A variety of theropods are known from the Mesozoic Era, the age of the dinosaurs.

Just as lions today are mainly found in Africa and tigers only in Asia, Allosaurus, for example, was widespread in the Jurassic of North America and south-western Europe, while the similarly sized Metriacanthosaurs lived in China. However, the region in between, i.e., between central Europe and East Asia, was so far terra incognita—no large Jurassic predatory dinosaurs were previously known from this huge region.

Postorbital of A. kyrgyzicus. A–D, left postorbital IGB 2-1 in lateral (A, stereophotographs), posterior (B), medial (C), and dorsal (D, stereophotographs) views. E, F, right postorbital IGB 2-2 in lateral (E) and medial (F) views. Abbreviations: g, groove; jf, jugal facet; ls, laterosphenoid contact; ob, orbital brow; pp, posterior process; sf, supratemporal fossa; sq, squamosal facet; st, step. Scale bar is 5 cm.

A new discovery has now significantly altered the situation: Alpkarakush kyrgyzicus is the name of the first theropod dinosaur found in Kyrgyzstan. The first remains of the fossil were discovered in 2006 by Kyrgyz paleontologist Aizek Bakirov.

The discovery site is located in the mountainous desert regions near the city of Tashkumyr in western Kyrgyzstan. The sediments of the Balabansai Formation exposed here were deposited during the Middle Jurassic period around 165 million years ago.

During several excavation campaigns between 2006 and 2023, skull bones, dorsal and pelvic vertebrae, fragments of the shoulder girdle and forelimbs as well as the almost complete pelvic girdle and hind limbs of a predatory dinosaur about 8–9 meters long were recovered.

It is a new genus and species with previously unknown characteristics. Particularly impressive is its extremely protruding “eyebrow” on the so-called postorbital bone, a skull bone behind the eye opening, which indicates the presence of a horn at that point. Other unique features are found on the dorsal vertebrae and the femur.

Left quadratojugal of A. kyrgyzicus, IGB 2-9, in lateral (A), posterior (B), and medial (C) views. Abbreviations: djp, articular facet for the dorsal jugal prong; dqc, dorsal quadrate contact; vjp, facet for the ventral jugal prong; vqc, ventral quadrat contact. Scale bar is 5 cm.

Comparisons with numerous other theropods show that the new species belongs to the metriacanthosaurids, and it is closely related to the large predatory dinosaurs of East Asia. Paleontologists suggest the origin of metriacanthosaurids and other important theropod groups in Southeast Asia, from where they spread to other continents via Central Asia and Europe.

“Although the affiliation of Alpkarakush with the metriacanthosaurids is not necessarily a surprise, this discovery closes a huge gap in our knowledge of the Jurassic theropods. It leads us to important new insights into the evolution and biogeography of these animals,” says Prof. Oliver Rauhut from the Bavarian Collection of Paleontology and Geology in Munich (SNSB-BSPG) and first author of the study published in the Zoological Journal of the Linnean Society.

Alpkarakush kyrgyzicus were also found at the site. Examination of the internal bone structure revealed that the large specimen was almost an adult, at least 17 years old, and certainly already sexually mature, while the smaller individual is a juvenile. Maybe a parent animal was on tour with its young 165 million years ago.

Digital photogammetric 3D models of all relevant bones of the Alpkarakush were generated. “These models are now available online and allow researchers worldwide to carry out follow-up studies and make 3D prints,” says co-author Dr. Oliver Wings, Director of the Bamberg Natural History Museum.

The fossil is named after Alpkarakush, a giant bird in the mythological Kyrgyz “Manas” epic, which often comes to the aid of the heroes in critical moments. The species name “kyrgyzicus” refers directly to the Kyrgyz Republic, the origin of the new predatory dinosaur.

Alpkarakush kyrgyzicus could even become the first original dinosaur skeleton ever to be exhibited in Kyrgyzstan: if enough supporters are found, a reconstruction is planned with the original bones in the National Historical Museum in Bishkek, pending the acquisition of the necessary funding.

More information: Oliver W M Rauhut et al, A new theropod dinosaur from the Callovian Balabansai Formation of Kyrgyzstan, Zoological Journal of the Linnean Society (2024). DOI: 10.1093/zoolinnean/zlae090

Journal information: Zoological Journal of the Linnean Society

Provided by The Bavarian Natural History Collections

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WFS News: Half-a-billion-year-old slug reveals mollusc origins

August 17th, 2024

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The fossil was initially referred to as “the plastic bag” because of its appearance

A half-a-billion-year-old spiny slug has shed light on the origins of animals like oysters and octopuses, researchers have said.

Scientists, including experts from the University of Oxford, have discovered a new species of mollusc that lived 500 million years ago.

The fossil, called Shishania aculeata, reveals that the earliest molluscs were flat, shell-less slugs covered in a protective spiny armour.

Shishania was initially referred to as “the plastic bag” because of its appearance.

First author Guangxu Zhang, a recent PhD graduate from China’s Yunnan University who discovered the specimens, said the fossils were “completely different” from any others he had seen.

Molluscs are animals that do not have a backbone and today come in many different forms, from snails to squids.

This diversity evolved very quickly a long time ago, and very few fossils have been left behind that chronicle their early evolution.

The new species was found in well-preserved fossils from eastern Yunnan Province in southern China, dating from a geological period approximately 514 million years ago.

The specimens are all only a few centimetres long and are covered in small spikey cones.

Some of the fossils were preserved upside down and show that the bottom of the animal was naked, with a muscular foot like that of a slug.

Experts suggest it would have used this food to creep across the seafloor.

Corresponding author associate prof Luke Parry, of the department of earth sciences at Oxford, said it showed “the very earliest mollusc ancestors were armoured spiny slugs”.

Its spines show an internal system of canals that are less than a hundredth of a millimetre in diameter.

These features show that the cones were secreted at their base by tiny protrusions of cells, which researchers compared to the workings of a natural 3D printer.

Source: Galya Dimitrova & PA Media,BBC News

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WFS News : Ammonites’ fate sealed by meteor strike that wiped out dinosaurs

June 29th, 2024

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Ammonites basking under the Late Cretaceous sun. Credit: Artwork by Callum Pursall

Ammonites were not in decline before their extinction, scientists have found

The marine mollusks with coiled shells, one of paleontology’s great icons, flourished in Earth’s oceans for more than 350 million years until they died out during the same chance event that wiped out the dinosaurs 66 million years ago.

Some paleontologists have argued that their demise was inevitable and that ammonite diversity was decreasing long before they went extinct at the end of the Cretaceous.

However, new research, published in Nature Communications and led by paleontologists at the University of Bristol, shows that their fate was not set in stone. Instead, the final chapter in ammonite evolutionary history is more complex.

“Understanding how and why biodiversity has changed through time is very challenging,” said lead author Dr. Joseph Flannery-Sutherland. “The fossil record tells us some of the story, but it is often an unreliable narrator. Patterns of diversity can just reflect patterns of sampling, essentially where and when we have found new fossil species, rather than actual biological history.

“Analyzing the existing Late Cretaceous ammonite fossil record as though it were the complete, global story is probably why previous researchers have thought they were in long-term ecological decline.”

To overcome this issue, the team assembled a new database of Late Cretaceous ammonite fossils to help fill in the sampling gaps in their record.

“We drew on museum collections to provide new sources of specimens rather than just relying on what had already been published,” said co-author Cameron Crossan, a 2023 graduate of the University of Bristol’s Palaeobiology MSc program. “This way we could be sure that we were getting a more accurate picture of their biodiversity prior to their total extinction.”

Credit: Pixabay/CC0 Public Domain

Using their database, the team then analyzed how ammonite speciation and extinction rates varied in different parts of the globe. If ammonites were in decline through the Late Cretaceous, then their extinction rates would have been generally higher than their speciation rates wherever the team looked. What the team instead found was that the balance of speciation and extinction changed both through geological time and between different geographic regions.

“These differences in ammonoid diversification around the world are a crucial part of why their Late Cretaceous story has been misunderstood,” said senior author Dr. James Witts of the Natural History Museum, London. “Their fossil record in parts of North America is very well sampled, but if you looked at this alone, then you might think that they were struggling, while they were actually flourishing in other regions. Their extinction really was a chance event and not an inevitable outcome.”

To find out what was responsible for the continued success of ammonites through the Late Cretaceous, the team looked at potential factors that might have caused their diversity to change through time. They were particularly interested in whether their speciation and extinction rates were driven mainly by environmental conditions like ocean temperature and sea level (the Court Jester Hypothesis), or by biological processes like pressure from predators and competition between ammonites themselves (the Red Queen Hypothesis).

“What we found was that the causes of ammonite speciation and extinction were as geographically varied as the rates themselves,” said co-author Dr. Corinne Myers of the University of New Mexico. “You couldn’t just look at their total fossil record and say that their diversity was driven entirely by changing temperature, for example. It was more complex than that and depended on where in the world they were living.”

“Paleontologists are frequently fans of silver bullet narratives for what drove changes in a group’s fossil diversity, but our work shows that things are not always so straightforward,” Dr. Flannery Sutherland concluded. “We can’t necessarily trust global fossil datasets and need to analyze them at regional scales. This way we can capture a much more nuanced picture of how diversity changed across space and through time, which also shows how variation in the balance of Red Queen versus Court Jester effects shaped these changes.”

More information: Late Cretaceous ammonoids show that drivers of diversification are regionally heterogeneous, Nature Communications (2024). DOI: 10.1038/s41467-024-49462-z

Journal information: Nature Communications

Source:Phys.org

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

WFS News: Shifts in marine community structures can predict future extinctions

June 26th, 2024

Riffin

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

A study using foraminifera fossils suggests that shifts in marine community structures can predict future extinctions, highlighting the role of historical data in forecasting climate change impacts on biodiversity.

For hundreds of millions of years, single-celled organisms known as foraminifera, which are microscopic and hard-shelled, have thrived in the oceans. These tiny creatures form the foundation of the food chain. The fossils of these ancient organisms provide insights into potential shifts in global biodiversity linked to our warming climate.

Using a high-resolution global dataset of planktonic foraminifera fossils that are among the richest biological archives available to science, researchers have found that major environmental stress events leading to mass extinctions are reliably preceded by subtle changes in how a biological community is composed, acting as a pre-extinction early warning signal.

Planktonic foraminifera fossils. Credit: Tracy Aze / University of Leeds

The results are in Nature, co-led by Anshuman Swain, a Junior Fellow in the Harvard Society of Fellows, a researcher in the Department of Organismic and Evolutionary Biology, and an affiliate of the Museum of Comparative Zoology. A physicist by training who applies networks to biological and paleontological data, Swain teamed with co-first author Adam Woodhouse at the University of Bristol to probe the global, community structure of ancient marine plankton that could serve as an early warning system for future extinction of ocean life.

“Can we leverage the past to understand what might happen in the future, in the context of global change?” said Swain, who previously co-authored a study about the formation of polar ice caps driving changes in marine plankton communities over the last 15 million years. “Our work offers new insight into how biodiversity responds spatially to global changes in climate, especially during intervals of global warmth, which are relevant to future warming projections.”

Leveraging Historical Data for Future Predictions

The researchers used the Triton database, developed by Woodhouse, to ascertain how the composition of foraminifera communities changed over millions of years – orders of magnitude longer time spans than are typically studied at this scale. They focused on the Early Eocene Climatic Optimum, the last major period of sustained high global temperatures since the dinosaurs, analogous to worst-case global warming scenarios.

They found that, before an extinction pulse of 34 million years ago, marine communities became highly specialized everywhere but southern high latitudes, implying that these micro-plankton migrated en masse to higher latitudes and away from the tropics. This finding indicates that community-scale changes like the ones seen in these migration patterns are evident in fossil records long before actual extinctions and losses in biodiversity occur.

The researchers thus think it’s important to place emphasis on monitoring the structure of biological communities to predict future extinctions.

According to Swain, the results from the foraminifera studies open avenues of inquiry into other organismal groups, including other marine life, sharks, and insects. Such studies may spark a revolution in an emerging field called paleoinformatics, or use large spatiotemporally resolved databases of fossil records to glean new insights into the future of Earth.

Reference: “Biogeographic response of marine plankton to Cenozoic environmental changes” by Anshuman Swain, Adam Woodhouse, William F. Fagan, Andrew J. Fraass and Christopher M. Lowery, 17 April 2024, Nature.
DOI: 10.1038/s41586-024-07337-9

WFS News,Simpsonigobius, new species of fossil fish

June 17th, 2024

Riffin

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

Gobies or Gobioidei are one of the most species-rich groups of marine and freshwater fish in Europe. Spending most of their lives on the bottom of shallow waterbodies, they make substantial contributions to the functioning of many ecosystems.

Fossil fish of the new genus †Simpsonigobius. Credit: Moritz Dirnberger

With the identification of a new genus of a fossil freshwater goby, students of the international master program Geobiology and Paleobiology at LMU and paleontologist Bettina Reichenbacher, professor at the Department of Earth and Environmental Sciences at LMU, have made a discovery that provides critical insights into the evolutionary history of these fish.

The find is reported in the Journal of Systematic Palaeontology.

Measuring up to 34 mm, the small fish of the new genus †Simpsonigobius were discovered in 18-million-year-old rocks in Turkey and are marked by a distinct combination of morphological features, including otoliths (hearing stones) with a unique shape.

Modern research techniques elucidate position in family tree

To determine the relationships of †Simpsonigobius within the gobioid phylogenetic tree, the researchers utilized a “total-evidence” phylogenetic dataset, which they enhanced in order to combine a total of 48 morphological characters and genetic data from five genes for 48 living and 10 fossil species.

In addition, the team employed “tip-dating” for fossil gobioid species for the first time. This is a phylogenetic method in which the age of the fossils (= tips) included in the phylogenetic tree is used to infer the timing of the evolutionary history of the entire group.

The results show that the new genus is the oldest skeleton-based member of the family Oxudercidae—which is classified among the “modern” gobies (families Gobiidae and Oxudercidae)—and the oldest freshwater goby within this modern group.

The tip-dating analysis estimated the emergence of the Gobiidae at 34.1 million years ago and that of the Oxudercidae at 34.8 million years ago, which is consistent with previous dating studies using other methods. Moreover, stochastic habitat mapping, in which the researchers incorporated fossil gobies for the first time, revealed that the gobies probably possessed broad salinity tolerance at the beginning of their evolutionary history, which challenges previous assumptions.

“The discovery of †Simpsonigobius not only adds a new genus to the Gobioidei, but also provides vital clues about the evolutionary timeline and habitat adaptations of these diverse fishes. Our research highlights the importance of analyzing fossil records using modern methods to achieve a more accurate picture of evolutionary processes,” says Reichenbacher.

First author Moritz Dirnberger, currently a doctoral candidate at the University of Montpellier, adds, “The findings are expected to pave the way for further studies on gobioid evolution and the role of environmental factors in shaping their diversity.”

More information: Moritz Dirnberger et al, A new freshwater gobioid from the Lower Miocene of Turkey in a significantly amended total evidence phylogenetic framework, Journal of Systematic Palaeontology (2024). DOI: 10.1080/14772019.2024.2340498

Journal information: Journal of Systematic Palaeontology

SOurce: PHYS.ORG.Editors notes

Provided by Ludwig Maximilian University of Munich

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