Oldest giant ichthyosaur discovery


Cymbospondylus

Cymbospondylus

From ScienceDaily, 23 December 2021, by the Natural History Museum of Los Angeles County in the USA:

The two-meter skull of a newly discovered species of giant ichthyosaur, the earliest known, is shedding new light on the marine reptiles’ rapid growth into behemoths of the Dinosaurian oceans, and helping us better understand the journey of modern cetaceans (whales and dolphins) to becoming the largest animals to ever inhabit the Earth.

While dinosaurs ruled the land, ichthyosaurs and other aquatic reptiles (that were emphatically not dinosaurs) ruled the waves, reaching similarly gargantuan sizes and species diversity. Evolving fins and hydrodynamic body-shapes seen in both fish and whales, ichthyosaurs swam the ancient oceans for nearly the entirety of the Age of Dinosaurs.

“Ichthyosaurs derive from an as yet unknown group of land-living reptiles and were air-breathing themselves,” says lead author Dr. Martin Sander, paleontologist at the University of Bonn and Research Associate with the Dinosaur Institute at the Natural History Museum of Los Angeles County (NHM). “From the first skeleton discoveries in southern England and Germany over 250 years ago, these ‘fish-saurians’ were among the first large fossil reptiles known to science, long before the dinosaurs, and they have captured the popular imagination ever since.”

Excavated from a rock unit called the Fossil Hill Member in the Augusta Mountains of Nevada, the well-preserved skull, along with part of the backbone, shoulder, and forefin, date back to the Middle Triassic (247.2-237 million years ago), representing the earliest case of an ichthyosaur reaching epic proportions. As big as a large sperm whale at more than 17 meters (55.78 feet) long, the newly named Cymbospondylus youngorum is the largest animal yet discovered from that time period, on land or in the sea. In fact, it was the first giant creature to ever inhabit the Earth that we know of.

“The importance of the find was not immediately apparent,” notes Dr. Sander, “because only a few vertebrae were exposed on the side of the canyon. However, the anatomy of the vertebrae suggested that the front end of the animal might still be hidden in the rocks. Then, one cold September day in 2011, the crew needed a warm-up and tested this suggestion by excavation, finding the skull, forelimbs, and chest region.”

The new name for the species, C. youngorum, honors a happy coincidence, the sponsoring of the fieldwork by Great Basin Brewery of Reno, owned and operated by Tom and Bonda Young, the inventors of the locally famous Icky beer which features an ichthyosaur on its label.

In other mountain ranges of Nevada, paleontologists have been recovering fossils from the Fossil Hill Member’s limestone, shale, and siltstone since 1902, opening a window into the Triassic. The mountains connect our present to ancient oceans and have produced many species of ammonites, shelled ancestors of modern cephalopods like cuttlefish and octopuses, as well as marine reptiles. All these animal specimens are collectively known as the Fossil Hill Fauna, representing many of C. youngorum’s prey and competitors.

C. youngorum stalked the oceans some 246 million years ago, or only about three million years after the first ichthyosaurs got their fins wet, an amazingly short time to get this big. The elongated snout and conical teeth suggest that C. youngorum preyed on squid and fish, but its size meant that it could have hunted smaller and juvenile marine reptiles as well.

The giant predator probably had some hefty competition. Through sophisticated computational modeling, the authors examined the likely energy running through the Fossil Hill Fauna’s food web, recreating the ancient environment through data, finding that marine food webs were able to support a few more colossal meat-eating ichthyosaurs. Ichthyosaurs of different sizes and survival strategies proliferated, comparable to modern cetaceans’ — from relatively small dolphins to massive filter-feeding baleen whales, and giant squid-hunting sperm whales.

Co-author and ecological modeler Dr. Eva Maria Griebeler from the University of Mainz in Germany notes, “due to their large size and resulting energy demands, the densities of the largest ichthyosaurs from the Fossil Hill Fauna including C. youngourum must have been substantially lower than suggested by our field census. The ecological functioning of this food web from ecological modeling was very exciting as modern highly productive primary producers were absent in Mesozoic food webs and were an important driver in the size evolution of whales.”

Whales and ichthyosaurs share more than a size range. They have similar body plans, and both initially arose after mass extinctions. These similarities make them scientifically valuable for comparative study. The authors combined computer modeling and traditional paleontology to study how these marine animals reached record-setting sizes independently.

“One rather unique aspect of this project is the integrative nature of our approach. We first had to describe the anatomy of the giant skull in detail and determine how this animal is related to other ichthyosaurs,” says senior author Dr. Lars Schmitz, Associate Professor of Biology at Scripps College and Dinosaur Institute Research Associate. “We did not stop there, as we wanted to understand the significance of the new discovery in the context of the large-scale evolutionary pattern of ichthyosaur and whale body sizes, and how the fossil ecosystem of the Fossil Hill Fauna may have functioned. Both the evolutionary and ecological analyses required a substantial amount of computation, ultimately leading to a confluence of modeling with traditional paleontology.”

They found that while both cetaceans and ichthyosaurs evolved very large body sizes, their respective evolutionary trajectories toward gigantism were different. Ichthyosaurs had an initial boom in size, becoming giants early on in their evolutionary history, while whales took much longer to reach the outer limits of huge. They found a connection between large size and raptorial hunting — think of a sperm whale diving down to hunt giant squid — and a connection between large size and a loss of teeth — think of the giant filter-feeding whales that are the largest animals ever to live on Earth.

Ichthyosaurs’ initial foray into gigantism was likely thanks to the boom in ammonites and jawless eel-like conodonts filling the ecological void following the end-Permian mass extinction. While their evolutionary routes were different, both whales and ichthyosaurs relied on exploiting niches in the food chain to make it really big.

“As researchers, we often talk about similarities between ichthyosaurs and cetaceans, but rarely dive into the details. That’s one way this study stands out, as it allowed us to explore and gain some additional insight into body size evolution within these groups of marine tetrapods,” says NHM’s Associate Curator of Mammalogy (Marine Mammals), Dr. Jorge Velez-Juarbe. “Another interesting aspect is that Cymbospondylus youngorum and the rest of the Fossil Hill Fauna are a testament to the resilience of life in the oceans after the worst mass extinction in Earth’s history. You can say this is the first big splash for tetrapods in the oceans.”

C. youngorum will be permanently housed at the Natural History Museum of Los Angeles County, where it is currently on view.

310-million-year-old horseshoe crab brain discovery


The brain (white at center) of an extinct horseshoe crab called Euproops danae was fossilized in a clay mineral called kaolinite. The whole crab stretches only about 10 millimeters. R. Bicknell

By Rebecca Dzombak:

August 20, 2021 at 8:00 am

How fossilization preserved a 310-million-year-old horseshoe crab’s brain

A newly analyzed specimen is a ‘one-in-a-million’ find, researchers say

Paleontologists can spend years carefully splitting rocks in search of the perfect fossil. But with a 310-million-year-old horseshoe crab brain, nature did the work, breaking the fossil in just the right way to reveal the ancient arthropod’s central nervous system.

Of all soft tissues, brains are notoriously difficult to preserve in any form (SN: 10/31/16). Stumbling across such a detailed specimen purely by chance was “a one-in-a-million find, if not rarer,” says evolutionary paleontologist Russell Bicknell of the University of New England in Armidale, Australia.

The fossilized brain is remarkably similar to the brains of modern horseshoe crabs, giving clues to the arthropods’ evolution, Bicknell and colleagues report July 26 in Geology. And the brain’s peculiar mode of preservation could point paleontologists toward new places to look for hard-to-find fossils of soft tissues.

4-year-old girl’s 220-million-year-old dinosaur footprint discovery


This 30 January 2020 video says about itself:

“Dino-mite” invention: Lily Wilder, 4, finds 215-million-year-old ‘two-footed’ dinosaur footprint

A girl from Wales has discovered a perfectly preserved 215-million-year-old dinosaur print, described as the ‘finest’ of its type found in 10 years.

Read more here.

Triassic marine reptile Atopodentatus


This 22 December 2020 video says about itself

The Triassic Reptile With “Two Faces”

Figuring out what this creature’s face actually looked like would take paleontologists years. But understanding this weird animal can help us shine a light on at least one way for ecosystems to bounce back from even the worst mass extinction.

Only Irish dinosaurs described


This December 2018 video says about itself:

Dinosaurs existed for over 170 million years and lived all over the Earth. You might expect to find fossil evidence of them everywhere you look, but only two dinosaur fossils have been found in Ireland.

Dr Mike Simms, Senior Curator of Natural History at National Museums Northern Ireland, explains why.

Read more on this story here.

From the University of Portsmouth in England:

Only dinosaurs found in Ireland described for the first time

November 26, 2020

Summary: The only dinosaur bones ever found on the island of Ireland have been formally confirmed for the first time by a team of experts. The two fossils are from two different dinosaurs, a four-legged plant-eater called Scelidosaurus and a two-legged meat-eater similar to Sarcosaurus.

The only dinosaur bones ever found on the island of Ireland have been formally confirmed for the first time by a team of experts from the University of Portsmouth and Queen’s University Belfast, led by Dr Mike Simms, a curator and palaeontologist at National Museums NI.

The two fossil bones were found by the late Roger Byrne, a schoolteacher and fossil collector, who donated them along with many other fossils to Ulster Museum. Analysis has confirmed they are from early Jurassic rocks found in Islandmagee, on the east coast of County Antrim.

Ulster Museum has announced plans to put them on display when it reopens after the latest rounds of restrictions are lifted.

Dr Simms, National Museums NI, said: “This is a hugely significant discovery. The great rarity of such fossils here is because most of Ireland’s rocks are the wrong age for dinosaurs, either too old or too young, making it nearly impossible to confirm dinosaurs existed on these shores. The two dinosaur fossils that Roger Byrne found were perhaps swept out to sea, alive or dead, sinking to the Jurassic seabed where they were buried and fossilised.”

The article, published in the Proceedings of the Geologists’ Association, is part of a larger project to document Jurassic rocks in Northern Ireland and draws on many fossils in Ulster Museum’s collections.

Originally it was assumed the fossils were from the same animal, but the team were surprised to discover that they were from two completely different dinosaurs. The study, employing the latest available technology, identified the type of dinosaur from which each came. One is part of a femur (upper leg bone) of a four-legged plant-eater called Scelidosaurus. The other is part of the tibia (lower leg bone) of a two-legged meat-eater similar to Sarcosaurus.

The University of Portsmouth team, researcher Robert Smyth, originally from Ballymoney, and Professor David Martill, used high-resolution 3D digital models of the fossils, produced by Dr Patrick Collins of Queen’s University Belfast, in their analysis of the bone fragments.

Robert Smyth said: “Analysing the shape and internal structure of the bones, we realised that they belonged to two very different animals. One is very dense and robust, typical of an armoured plant-eater. The other is slender, with thin bone walls and characteristics found only in fast-moving two-legged predatory dinosaurs called theropods.”

“Despite being fragmentary, these fossils provide valuable insight on a very important period in dinosaur evolution, about 200 million years ago. It’s at this time that dinosaurs really start to dominate the world’s terrestrial ecosystems.”

Professor Martill said: “Scelidosaurus keeps on turning up in marine strata, and I am beginning to think that it may have been a coastal animal, perhaps even eating seaweed, like marine iguanas do today.”

To find out when the fossils will go on display at the Ulster Museum follow @ulstermuseum on Twitter, @ulstermuseumbelfast on Facebook and @ulstermuseum on Instagram.

Extinct walrus species discovery in California, USA


This July 2020 video says about itself:

The rise and fall of ancient walruses, and how modern ones got their tusks, is a story that spans almost 20 million years. And while there are parts of the story that we’re still trying to figure out, it looks like tusks didn’t have anything to do with how or what these animals ate.

From ScienceDaily:

Paleontologists uncover three new species of extinct walruses in Orange County, California

Study gives insight to tusk evolution of the marine mammal

November 16, 2020

Millions of years ago, in the warm Pacific Ocean off the coast of Southern California, walrus species without tusks lived abundantly.

But in a new study, Cal State Fullerton paleontologists have identified three new walrus species discovered in Orange County and one of the new species has “semi-tusks” — or longer teeth.

The other two new species don’t have tusks and all predate the evolution of the long iconic ivory tusks of the modern-day walrus, which lives in the frigid Arctic.

The researchers describe a total of 12 specimens of fossil walruses from Orange, Los Angeles and Santa Cruz counties, all estimated to be 5 to 10 million years old. The fossils represent five species, with two of the three new species represented by specimens of males, females and juveniles.

Their research, which gives insights on the dental and tusk evolution of the marine mammal, was published today in the Journal of Vertebrate Paleontology.

Geology graduate Jacob Biewer, and his research adviser James F. Parham, associate professor of geological sciences, are authors of the study, based on fossil skull specimens.

Parham and Biewer worked with Jorge Velez-Juarbe, an expert in marine mammals at the Natural History Museum of Los Angeles County, who is a co-author of the paper. Velez-Juarbe is a former postdoctoral scholar in Parham’s lab and has collaborated on other CSUF fossil research projects. Parham is a research associate at the museum, which provides research opportunities for him and his students.

The researchers teamed to study and describe the anatomy of the specimens, most of which are part of the museum’s collection.

“Orange County is the most important area for fossil walruses in the world,” said Biewer, first author of the paper who conducted the research for his master’s thesis. “This research shows how the walruses evolved with tusks.”

Extinct Walrus Species Get Names

Today, there is only one walrus species and its scientific name is Odobenus.

For the new species found in Orange County, the researchers named the semi-tusked walrus, Osodobenus eodon, by combining the words Oso and Odobenus. Another is named Pontolis kohnoi in honor of Naoki Kohno, a fossil walrus researcher from Japan. Both of these fossils were discovered in the Irvine, Lake Forest and Mission Viejo areas.

Osodobenus eodon and Pontolis kohnoi are both from the same geological rock layer as the 2018 study by Parham and his students of another new genus and species of a tuskless walrus, Titanotaria orangensis, named after CSUF Titans. These fossils were found in the Oso Member of the Capistrano Formation, a geological formation near Lake Forest and Mission Viejo.

The third new walrus species, Pontolis barroni, was found in Aliso Viejo, near the 73 Toll Road. It is named after John Barron, a retired researcher from the U.S.Geological Survey and world expert on the rock layer where the specimens were found, Parham said.

Analysis of these specimens show that fossil walrus teeth are more variable and complex than previously considered. Most of the new specimens predate the evolution of tusks, Parham said.

“Osodobenus eodon is the most primitive walrus with tusk-like teeth,” Parham said. “This new species demonstrates the important role of feeding ecology on the origin and early evolution of tusks.”

Biewer explained that his work focused on getting a better understanding of the evolutionary history of the walrus in regards to its teeth.

“The importance of dental evolution is that it shows the variability within and across walrus species. Scientists assumed you could identify certain species just based on the teeth, but we show how even individuals of the same species could have variability in their dental setup,” said Biewer, who earned a master’s degree in geology in 2019.

“Additionally, everyone assumes that the tusks are the most important teeth in a walrus, but this research further emphasizes how tusks were a later addition to the history of walruses. The majority of walrus species were fish eaters and adapted to catching fish, rather than using suction feeding on mollusks like modern walruses.”

Biewer, now a paleontologist in the Modesto area, also examined whether climate changes in the Pacific Ocean had an impact on ancient walruses. His work suggests that a rise in water temperature helped to boost nutrients and planktonic life, and played a role in the proliferation of walruses about 10 million years ago, which may have contributed to their diversity.

Background

For the fossil walrus research project, geology graduate Jacob Biewer spent hours in the lab measuring and describing the walrus bones.

“I sat many hours with a handy caliper taking notes on the lengths of teeth and width of skulls, among many other measurements,” he said. “Describing bones is much more in-depth and meticulous than it sounds. There are traits that the bones of each walrus species have — the size, shape and number of teeth. I recorded how the bones are different from, or similar to, other extinct walrus species.”

Biewer, a paleontologist who lives in Modesto, noted that despite the pandemic, he and Parham worked on the scientific paper with 300 miles of social distancing.

Completing his first journal publication, based on his master’s work, and conducting the research project helped him to understand scientific methods and techniques that he now uses in his career, where he monitors construction sites for paleontological resources. He also teaches undergraduate geology courses at Cal State Stanislaus, where he earned a bachelor’s degree in geology, and is considering pursuing a doctorate.

“The experiences I had in conducting this research, especially the presentations at national paleontological conferences, led to a big increase in my confidence in my scientific abilities,” Biewer said. “I credit my time working with Dr. Parham directly to the achievements in my current employment — from the skills he imparted to the doors he helped open.”

Permian-Triassic mass extinction and volcanoes, new research


This 2017 video is called Fireball Earth: The Permian Extinction – History Documentary.

From Tohoku University in Japan:

Large volcanic eruption caused the largest mass extinction

November 10, 2020

Researchers in Japan, the US and China say they have found more concrete evidence of the volcanic cause of the largest mass extinction of life. Their research looked at two discrete eruption events: one that was previously unknown to researchers, and the other that resulted in large swaths of terrestrial and marine life going extinct.

There have been five mass extinctions since the divergent evolution of early animals 450 — 600 million years ago. The third was the largest one and is thought to have been triggered by the eruption of the Siberian Traps — a large region of volcanic rock known as a large igneous province. But the correlation between the eruption and mass extinction has not yet been clarified.

Sedimentary mercury enrichments, proxies for massive volcanic events, have been detected in dozens of sedimentary rocks from the end of the Permian. These rocks have been found deposited inland, in shallow seas and central oceans, but uncertainty remains as to their interpretation. Mercury can be sourced from either direct atmospheric deposition from volcanic emissions and riverine inputs from terrestrial organic matter oxidation when land/plant devastation — referred to as terrestrial ecological disturbance — occurs.

The largest mass extinction occurred at the end of the Permian — roughly 252 million years ago. This mass extinction was marked by the transition from the divergence of the Paleozoic reptiles and marine animals like brachiopods and trilobites to Mesozoic dinosaurs and marine animals such as mollusks. Approximately 90% of species disappeared at the end of the Permian.

Current professor emeritus at Tohoku University, Kunio Kaiho led a team that looked into possible triggers of the largest mass extinction. They took sedimentary rock samples from two places — southern China and Italy — and analyzed the organic molecules and mercury (Hg) in them. They found two discrete coronene-Hg enrichments coinciding with the first terrestrial ecological disturbance and the following mass extinction in both areas.

“We believe this to be the product of large volcanic eruptions because the coronene anomaly was formed by abnormally high temperature combustion,” says professor Kaiho. “High temperature magma or asteroid/comet impacts can make such a coronene enrichment.

From the volcanic aspect, this could have occurred because of the higher temperature combustion of living and fossil organic matter from lava flows and horizontally intruded magma (sill) into the sedimentary coal and oil. The different magnitude of the two coronene-mercury enrichments shows that the terrestrial ecosystem was disrupted by smaller global environmental changes than the marine ecosystem. The duration between the two volcanic events is tens of thousands of years.”

Huge volcanic eruptions can produce sulfuric acid aerosols in the stratosphere and carbon dioxide in the atmosphere, which causes global climate changes. This rapid climate change is believed to be behind the loss of land and marine creatures.

Coronene is a highly condensed six-ring polycyclic aromatic hydrocarbon, which requires significantly higher energy to form as compared to smaller PAHs. Therefore, high temperature volcanic combustion can cause the coronene enrichments. This means that high temperature combustion of hydrocarbons in the sedimentary rocks by lateral intrusion of magmas formed CO2 and CH4 causing high pressure and eruption to induce global warming and the mass extinction. The coronene-mercury concentration firstly evidenced that volcanic hydrocarbon combustion helped contribute to the extinction through global warming.

Kaiho’s team is now studying other mass extinctions in the hopes of further understanding the cause and processes behind them.

Titanosaur dinosaur infected by parasites


An illustration of the titanosaur with open wounds caused by parasites. Hugo Cafasso

From New Scientist:

Ancient parasites in a titanosaur’s bones made it look like a zombie

20 November 2020

By Joshua Rapp Learn

Some of the oldest evidence of bone disease may have been caused by tiny 83-million-year-old parasites infecting a titanosaur, which are among the largest land animals that ever lived. This is the first discovery of parasites in a dinosaur bone.

“It’s a new kind of parasite,” says Aline Ghilardi at the Federal University of Rio Grande do Norte in Brazil. “We don’t have anything similar to it.”

This fossilised parasite was seen in a sample from a dwarf titanosaur.

World´s first animals, Greenland discovery


This 21 July 2020 video is called The Cambrian Explosion and the evolutionary origin of animals with Professor Paul Smith.

From Uppsala University in Sweden:

Half-a-billion year old microfossils may yield new knowledge of animal origins

November 9, 2020

When and how did the first animals appear? Science has long sought an answer. Uppsala University researchers and colleagues in Denmark have now jointly found, in Greenland, embryo-like microfossils up to 570 million years old, revealing that organisms of this type were dispersed throughout the world. The study is published in Communications Biology.

“We believe this discovery of ours improves our scope for understanding the period in Earth’s history when animals first appeared — and is likely to prompt many interesting discussions,” says Sebastian Willman, the study’s first author and a palaeontologist at Uppsala University.

The existence of animals on Earth around 540 million years ago (mya) is well substantiated. This was when the event in evolution known as the “Cambrian Explosion” took place. Fossils from a huge number of creatures from the Cambrian period, many of them shelled, exist. The first animals must have evolved earlier still; but there are divergent views in the research community on whether the extant fossils dating back to the Precambrian Era are genuinely classifiable as animals.

The new finds from the Portfjeld Formation in the north of Greenland may help to enhance understanding of the origin of animals. In rocks that are 570-560 mya, scientists from Uppsala University, the University of Copenhagen and the Geological Survey of Denmark and Greenland have found microfossils of what might be eggs and animal embryos. These are so well preserved that individual cells, and even intracellular structures, can be studied. The organisms concerned lived in the shallow coastal seas around Greenland during the Ediacaran period, 635-541 mya. The immense variability of microfossils has convinced the researchers that the complexity of life in that period must have been greater than has hitherto been known.

Similar finds were uncovered in southern China’s Doushantuo Formation, which is nearly 600 million years old, over three decades ago. Since then, researchers have been discussing what kinds of life form the microfossils represented, and some think they are eggs and embryos from primeval animals. The Greenland fossils are somewhat younger than, but largely identical to, those from China.

The new discovery means that the researchers can also say that these organisms were spread throughout the world. When they were alive, most continents were spaced out south of the Equator. Greenland lay where the expanse of the Southern Ocean (surrounding Antarctica) is now, and China was roughly at the same latitude as present-day Florida.

“The vast bedrock, essentially unexplored to date, of the north of Greenland offers opportunities to understand the evolution of the first multicellular organisms, which in turn developed into the first animals that, in their turn, led to us,” Sebastian Willman says.