Tag: dinosaur

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Archaeological Mystery Based on Forgery

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A 280-million-year-old fossil that has baffled researchers for decades has been shown to be, in part, a forgery following new examination of the remnants.

The discovery has led the team led by Dr Valentina Rossi of University College Cork, Ireland (UCC) to urge caution in how the fossil is used in future research.
Tridentinosaurus antiquus was discovered in the Italian alps in 1931 and was thought to be an important specimen for understanding early reptile evolution.
Its body outline, appearing dark against the surrounding rock, was initially interpreted as preserved soft tissues. This led to its classification as a member of the reptile group Protorosauria.
However, this new research, published in the scientific journal Palaeontology, reveals that the fossil renowned for its remarkable preservation is mostly just black paint on a carved lizard-shaped rock surface (https://onlinelibrary.wiley.com/doi/10.1111/pala.12690).
The purported fossilized skin had been celebrated in articles and books but never studied in detail. The somewhat strange preservation of the fossil had left many experts uncertain about what group of reptiles this strange lizard-like animal belonged to and more generally its geological history.
Dr Rossi, of UCC’s School of Biological, Earth and Environmental Sciences, said:
“Fossil soft tissues are rare, but when found in a fossil they can reveal important biological information, for instance, the external colouration, internal anatomy and physiology.
“The answer to all our questions was right in front of us, we had to study this fossil specimen in details to reveal its secrets – even those that perhaps we did not want to know”.
The microscopic analysis showed that the texture and composition of the material did not match that of genuine fossilized soft tissues.
Preliminary investigation using UV photography revealed that the entirety of the specimen was treated with some sort of coating material. Coating fossils with varnishes and/or lacquers was the norm in the past and sometimes is still necessary to preserve a fossil specimen in museum cabinets and exhibits. The team was hoping that beneath the coating layer, the original soft tissues were still in good condition to extract meaningful palaeobiological information.
The findings indicate that the body outline of Tridentinosaurus antiquus was artificially created, likely to enhance the appearance of the fossil. This deception misled previous researchers, and now caution is being urged when using this specimen in future studies.

https://www.ucc.ie/en/news/2024/mystery-solved-the-oldest-fossil-reptile-from-the-alps-is-an-historical-forgery.html

AR #125

“Jurassic Soft Tissue”

Stephen Robbins, Ph.D.

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Did Killing off the Dinosaurs Take More than Rocks from Space?

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What wiped out the dinosaurs? A meteorite plummeting to Earth is only part of the story, a new study suggests. Climate change triggered by massive volcanic eruptions may have ultimately set the stage for the dinosaur extinction, challenging the traditional narrative that a meteorite alone delivered the final blow to the ancient giants. That’s according to a study published in Science Advances, co-authored by Don Baker, a professor in McGill University’s Department of Earth and Planetary Sciences ( https://www.science.org/doi/10.1126/sciadv.adg8284 ).

The research team delved into volcanic eruptions of the Deccan Traps—a vast and rugged plateau in Western India formed by molten lava. Erupting a staggering one million cubic kilometers of rock, it may have played a key role in cooling the global climate around 65 million years ago.
The work took researchers around the world, from hammering out rocks in the Deccan Traps to analyzing the samples in England and Sweden.
In the lab, the scientists estimated how much sulfur and fluorine was injected into the atmosphere by massive volcanic eruptions in the 200,000 years before the dinosaur extinction.
Remarkably, they found the sulfur release could have triggered a global drop in temperature around the world—a phenomenon known as a volcanic winter.
“Our research demonstrates that climatic conditions were almost certainly unstable, with repeated volcanic winters that could have lasted decades, prior to the extinction of the dinosaurs. This instability would have made life difficult for all plants and animals and set the stage for the dinosaur extinction event. Thus our work helps explain this significant extinction event that led to the rise of mammals and the evolution of our species,” said Prof. Don Baker.

AR #101

Facing the Extinction Threat

by William B. Stoecker

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Pliosaur Carcass, the Oldest Sea Monster Yet Found

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The fossils of a 170-million-year-old ancient marine reptile from the Age of Dinosaurs have been identified as the oldest-known mega-predatory pliosaur – a group of ocean-dwelling reptiles closely related to the famous long-necked plesiosaurs. The findings are rare and add new knowledge to the evolution of plesiosaurs. The study has been published in the journal Scientific Reports (https://www.nature.com/articles/s41598-023-43015-y).

The fossils were found 40 years ago in north-eastern France. An international team of palaeontologists have now analized them and identified them as a new pliosaur genus: Lorrainosaurus.
Pliosaurs were a type of plesiosaur with short necks and massive skulls. They appeared over 200 million years ago, but remained minor components of marine ecosystems until suddenly developing into enormous apex predators. The new study shows that this adaptive shift followed feeding niche differentiation and the global decline of other predatory marine reptiles over 170 million years ago.
Lorrainosaurus is the oldest large-bodied pliosaur represented by an associated skeleton. It had jaws over 1.3 m long with large conical teeth and a bulky ‘torpedo-shaped’ body propelled by four flipper-like limbs.
“Lorrainosaurus was one of the first truly huge pliosaurs. It gave rise to a dynasty of marine reptile mega-predators that ruled the oceans for around 80 million years,” explains Sven Sachs, a researcher at the Naturkunde-Museum Bielefeld, who led the study.
This giant reptile probably reached over 6 m from snout to tail, and lived during the early Middle Jurassic period. Intriguingly, very little is known about plesiosaurs from that time.
“Our identification of Lorrainosaurus as one of the earliest mega-predatory pliosaurs demonstrates that these creatures emerged immediately after a landmark restructuring of marine predator ecosystems across the Early-to-Middle Jurassic boundary, some 175 to 171 million years ago. This event profoundly affected many marine reptile groups and brought mega-predatory pliosaurids to dominance over ‘fish-like’ ichthyosaurs, ancient marine crocodile relatives, and other large-bodied predatory plesiosaurs”, adds Daniel Madzia from the Institute of Paleobiology of the Polish Academy of Sciences, who co-led the study.
Pliosaurs were some of the most successful marine predators of their time. “Famous examples, such as Pliosaurus and Kronosaurus – some of the world’s largest pliosaurs – were absolutely enormous with body-lengths exceeding 10 m. They were ecological equivalents of today’s Killer whales and would have eaten a range of prey including squid-like cephalopods, large fish and other marine reptiles. These have all been found as preserved gut contents”, said senior co-author Benjamin Kear, Curator of Vertebrate Palaeontology and Researcher in Palaeontology at The Museum of Evolution, Uppsala University.
The recovered bones and teeth of Lorrainosaurus represent remnants of what was once a complete skeleton that decomposed and was dispersed across the ancient sea floor by currents and scavengers.
“The remains were unearthed in 1983 from a road cutting near Metz in Lorraine, north-eastern France. Palaeontology enthusiasts from the Association minéralogique et paléontologique d’Hayange et des environs recognised the significance of their discovery and donated the fossils to the Natural History Museum in Luxembourg”, said co-author Ben Thuy, Curator at the Natural History Museum in Luxembourg.

AR #119

The Dragon Factor

by William B. Stoecker

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The Bird Beak Mystery Said Solved

Fossilized fragments of a skeleton, hidden within a rock the size of a grapefruit, have helped upend one of the longest-standing assumptions about the origins of modern birds.

Researchers Researchers from the University of Cambridge and the Natuurhistorisch Museum Maastricht have found evidence that one of the key skull features that characterizes 99% of modern birds – a mobile beak – evolved before the mass extinction event that killed all large dinosaurs, 66 million years ago (https://www.nature.com/articles/s41586-022-05445-y).


This finding also suggests, say the scientists, that the skulls of ostriches, emus and their relatives evolved ‘backwards’, reverting to a more primitive condition after modern birds arose.


Using CT scanning techniques, the Cambridge team identified bones from the palate, or the roof of the mouth, of a new species of large ancient bird, which they named Janavis finalidens. It lived at the very end of the Age of Dinosaurs and was one of the last toothed birds to ever live. The arrangement of its palate bones shows that this ‘dino-bird’ had a mobile, dexterous beak, almost indistinguishable from that of most modern birds.


For more than a century, it had been assumed that the mechanism enabling a mobile beak evolved after the extinction of the dinosaurs. However, the new discovery, reported in the journal Nature, suggests that our understanding of how the modern bird skull came to be needs to be re-evaluated.


Each of the roughly 11,000 species of birds on Earth today is classified into one of two over-arching groups, based on the arrangement of their palate bones. Ostriches, emus and their relatives are classified into the palaeognath, or ‘ancient jaw’ group, meaning that, like humans, their palate bones are fused together into a solid mass.


All other groups of birds are classified into the neognath, or ‘modern jaw’ group, meaning that their palate bones are connected by a mobile joint. This makes their beaks much more dexterous, helpful for nest-building, grooming, food-gathering, and defence.


The two groups were originally classified by Thomas Huxley, the British biologist known as ‘Darwin’s Bulldog’ for his vocal support of Charles Darwin’s theory of evolution. In 1867, he divided all living birds into either the ‘ancient’ or ‘modern’ jaw groups. Huxley’s assumption was that the ‘ancient’ jaw configuration was the original condition for modern birds, with the ‘modern’ jaw arising later.


“This assumption has been taken as a given ever since,” said Dr Daniel Field from Cambridge’s Department of Earth Sciences, the paper’s senior author. “The main reason this assumption has lasted is that we haven’t had any well-preserved fossil bird palates from the period when modern birds originated.”


The fossil, Janavis, was found in a limestone quarry near the Belgian-Dutch border in the 1990s and was first studied in 2002. It dates from 66.7 million years ago, during the last days of the dinosaurs. Since the fossil is encased in rock, scientists at the time could only base their descriptions on what they could see from the outside. They described the bits of bone sticking out from the rock as fragments of skull and shoulder bones, and put the unremarkable-looking fossil back in storage.

https://www.cam.ac.uk/stories/the-last-toothed-bird


AR #128

Akhenaten, the Bird King

by Jonathon Perrin

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Killing the Dinosaurs: the Mega Volcano Link

The biological history of the Earth has been punctuated by mass extinctions that wiped out a vast majority of living species in a geological instant.

Based on evidence in the fossil record, scientists have identified five such events that reshaped life on Earth, the most familiar of which brought about the demise of the mighty dinosaurs at the end of the Cretaceous Period 66 million years ago.


What caused these catastrophes remains a matter of keen scientific debate. Some scientists argue that comets or asteroids that crashed into Earth were the most likely agents of mass destruction, while others point fingers at large volcanic eruptions.


Dartmouth Assistant Professor of Earth Sciences Brenhin Keller belongs to the latter camp. In a new study published in the Proceeding of the National Academy of Sciences (PNAS), Keller and his co-authors make a strong case for volcanic activity being the key driver of mass extinctions. Their study provides the most compelling quantitative evidence so far that the link between major volcanic eruptions and wholesale species turnover is not simply a matter of chance.


Four of the five mass extinctions are contemporaneous with a type of volcano called a flood basalt, the researchers say. These are a series of eruptions (or one giant one) that flood vast areas with lava in the blink of a geological eye, a mere million years. They leave behind giant fingerprints as evidence—extensive regions of step-like, igneous rock that geologists call large igneous provinces.


To count as “large,” an igneous province must contain at least 100,000 cubic kilometers of magma. For scale, the 1980 eruption of Mount St. Helens involved less than one cubic kilometer of magma.


In fact, a series of eruptions in what is now known as Siberia triggered the most destructive of the mass extinctions about 252 million years ago, releasing a gigantic pulse of carbon dioxide into the atmosphere and nearly choking off all life. Bearing witness are the Siberian Traps, a large region of volcanic rock roughly the size of Australia.


Volcanic eruptions also rocked the Indian subcontinent around the time of the great dinosaur die-off, creating what is known today as the Deccan plateau. This, much like an asteroid strike, would have had far-reaching global effects, blanketing the atmosphere in dust and toxic fumes, asphyxiating dinosaurs and other life.


“It seems like these large igneous provinces line up in time with mass extinctions and other significant climatic and environmental events,” says Theodore Green ’21, lead author of the paper.


Theodore Green ’21, left, and Assistant Professor of Earth Sciences Brenhin Keller were authors of the study.


On the other hand, the researchers say, the theories in favor of annihilation by asteroid impact hinge upon the Chicxulub impactor, a space rock that crash-landed into Mexico’s Yucatan Peninsula around the same time that the dinosaurs went extinct.

https://home.dartmouth.edu/news/2022/09/what-killed-dinosaurs-and-other-life-earth

AR Issue #70

How Old Is The Earth, Really?

By Stephen E. Robbins, Ph.D

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New Evidence of Early Humans in America

About 37,000 years ago, a mother mammoth and her calf met their end at the hands of human beings.

Bones from the butchering site record how humans shaped pieces of their long bones into disposable blades to break down their carcasses, and rendered their fat over a fire. But a key detail sets this site apart from others from this era. It’s in New Mexico – a place where most archaeological evidence does not place humans until tens of thousands of years later.


A recent study led by scientists with The University of Texas at Austin finds that the site offers some of the most conclusive evidence for humans settling in North America much earlier than conventionally thought.


The researchers revealed a wealth of evidence rarely found in one place. It includes fossils with blunt-force fractures, bone flake knives with worn edges, and signs of controlled fire. And thanks to carbon dating analysis on collagen extracted from the mammoth bones, the site also comes with a settled age of 36,250 to 38,900 years old, making it among the oldest known sites left behind by ancient humans in North America.


“What we’ve got is amazing,” said lead author Timothy Rowe, a paleontologist and a professor in the UT Jackson School of Geosciences. “It’s not a charismatic site with a beautiful skeleton laid out on its side. It’s all busted up. But that’s what the story is.”


The findings were published in Frontiers in Ecology and Evolution.


Rowe does not usually research mammoths or humans. He got involved because the bones showed up in his backyard, literally. A neighbor spotted a tusk weathering from a hillslope on Rowe’s New Mexico property in 2013. When Rowe went to investigate, he found a bashed-in mammoth skull and other bones that looked deliberately broken. It appeared to be a butchering site. But suspected early human sites are shrouded in uncertainty. It can be notoriously difficult to determine what was shaped by nature versus human hands.


This uncertainty has led to debate in the anthropological community about when humans first arrived in North America. The Clovis culture, which dates to 16,000 years ago, left behind elaborate stone-wrought tools. But at older sites where  stone tools are absent, the evidence gets more subjective, said retired Texas State University Professor Mike Collins, who was not involved with this paper and who oversaw research at Gault, a well-known archaeological site near Austin with an abundance of Clovis and pre-Clovis artifacts.


Although the mammoth site lacks clearly associated stone tools, Rowe and his co-authors discovered an array of supporting evidence by putting samples from the site through scientific analyses in the lab.


Based on genetic evidence from Indigenous populations in South and Central America and artifacts from other archaeological sites, some scientists have proposed that North America had at least two founding populations: the Clovis and a pre-Clovis society with a different genetic lineage.


The researchers suggest that New Mexico site, with its age and bone tools instead of elaborate stone technology, may lend support to this theory. Collins said the study adds to a growing body of evidence for pre-Clovis societies in North America while providing a toolkit that can help others find evidence that may have been otherwise overlooked.
The research was funded by the Jackson School, the National Science Foundation, and the W.J.J. Gordon Foundation.

https://news.utexas.edu/2022/08/01/new-mexico-mammoths-among-best-evidence-for-early-humans-in-north-america/

AR #108

Calico, California and the Early Man Dispute

by Michael Cremo

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Fresh Water Plesiosaurs in the Sahara

Fossils of small plesiosaurs, long-necked marine reptiles from the age of dinosaurs, have been found in a 100-million year old river system that is now Morocco’s Sahara Desert. This discovery suggests some species of plesiosaur, traditionally thought to be sea creatures, may have lived in freshwater.

Plesiosaurs, first found in 1823 by fossil hunter Mary Anning, were prehistoric reptiles with small heads, long necks, and four long flippers. They inspired reconstructions of the Loch Ness Monster, but unlike the monster of Loch Ness, plesiosaurs were marine animals – or were widely thought to be.


Now, scientists from the University of Bath and University of Portsmouth in the UK, and Université Hassan II in Morocco, have reported small plesiosaurs from a Cretaceous-aged river in Africa, in the journal Cretaceous Research.
The fossils include bones and teeth from three-meter long adults and an arm bone from a 1.5 meter long baby. They hint that these creatures routinely lived and fed in freshwater, alongside frogs, crocodiles, turtles, fish, and the huge aquatic dinosaur Spinosaurus.


These fossils suggest the plesiosaurs were adapted to tolerate freshwater, possibly even spending their lives there, like today’s river dolphins.


“It’s scrappy stuff, but isolated bones actually tell us a lot about ancient ecosystems and animals in them. They’re so much more common than skeletons, they give you more information to work with” said Dr. Nick Longrich, corresponding author on the paper.


“The bones and teeth were found scattered and in different localities, not as a skeleton. So each bone and each tooth is a different animal. We have over a dozen animals in this collection.”


Whilst bones provide information on where animals died, the teeth are interesting because they were lost while the animal was alive – so they show where the animals lived.


What’s more, the teeth show heavy wear, like those fish-eating dinosaur Spinosaurus found in the same beds.
The scientists say that implies the plesiosaurs were eating the same food- chipping their teeth on the armored fish that lived in the river. This hints they spent a lot of time in the river, rather than being occasional visitors.
While marine animals like whales and dolphins wander up rivers, either to feed or because they’re lost, the number of plesiosaur fossils in the river suggest that’s unlikely.


A more likely possibility is that the plesiosaurs were able to tolerate fresh and salt water, like some whales, such as the beluga whale.


It’s even possible that the plesiosaurs were permanent residents of the river, like modern river dolphins. The plesiosaurs’ small size would have let them hunt in shallow rivers, and the fossils show an incredibly rich fish fauna.
Dr Longrich said: “We don’t really know why the plesiosaurs are in freshwater.


“It’s a bit controversial, but who’s to say that because we paleontologists have always called them ‘marine reptiles’, they had to live in the sea? Lots of marine lineages invaded freshwater.”

https://www.bath.ac.uk/announcements/plesiosaur-fossils-found-in-the-sahara-suggest-they-werent-just-marine-animals/

AR #86

Nessie Makes a Comeback

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Dinosaurs Got Sick Too

Researchers discover first evidence indicating dinosaur respiratory infection

The scientists from around the country, including University of New Mexico Research Assistant Professor Ewan Wolff, discovered the first evidence of a unique respiratory infection in the fossilized remains of a dinosaur that lived nearly 150 million years ago.

The study, “The first occurrence of an avian‑style respiratory infection in a non‑avian dinosaur,” was recently published in the Scientific Report.

Researchers examined the remains of an immature diplodocid – a long-necked herbivorous sauropod dinosaur, like “Brontosaurus” – dating back to the Late Jurassic Period of the Mesozoic Era. The dinosaur nicknamed “Dolly,” discovered in southwest Montana, had evidence of an infection in the area of its neck vertebrae.

The study, led by Cary Woodruff of the Great Plains Dinosaur Museum, identified never before seen abnormal bony protrusions that had an unusual shape and texture. These protrusions were located in an area of each bone where they would have been penetrated by air sacs. Air sacs are non-oxygen exchanging parts of the respiratory system in modern birds that are also present in dinosaurs. The air sacs would have ultimately connected to “Dolly’s” lungs and formed part of the dinosaur’s complex respiratory system. CT imaging of the irregular protrusions revealed that they were made of abnormal bone that most likely formed in response to an infection.

“We’ve all experienced these same symptoms – coughing, trouble breathing, fever and here’s a 150-million-year-old dinosaur that likely felt as miserable as we all do when we’re sick.” Woodruff said.

Researchers say these findings are significant because Dolly was considered a non-avian dinosaur, and sauropods, like Dolly, did not evolve to become birds; only avian theropods evolved into birds. The authors speculate this respiratory infection could have been caused by a fungal infection similar to aspergillosis, a common respiratory illness that affects birds and reptiles today and can lead to bone infections. In addition to documenting the first occurrence of such a respiratory infection in a dinosaur, this fossilized infection also has important anatomical implications for the respiratory system of sauropod dinosaurs.

“This fossil infection in Dolly not only helps us trace the evolutionary history of respiratory-related diseases back in time, but it also gives us a better understanding of what kinds of diseases dinosaurs were susceptible to,” Woodruff said.

“This would have been a remarkably, visibly sick sauropod,” Wolff said. “We always think of dinosaurs as big and tough, but they got sick. They had respiratory illnesses like birds do today, in fact, maybe even the same devastating infections in some cases.”

The researchers suggest that if Dolly had been infected with an aspergillosis-like respiratory infection, it likely experienced flu or pneumonia-like symptoms such as weight loss, coughing, fever and breathing difficulties. As aspergillosis can be fatal in birds if untreated, a potentially similar infection in Dolly could have ultimately caused the death of the animal.

“We have to continue to expand our knowledge of ancient diseases. If we look hard enough, we may begin to understand more about the evolution of immunity and infectious disease,” Wolff said. “When we work together between multiple specialties – veterinarians, anatomists, paleontologists, paleopathologists, and radiologists we can come away with a more complete picture of ancient disease.” 

Great Plains Dinosaur Museum, University of New Mexico

The ‘Silurian Hypothesis’ Reconsidered
AR #130