Triassic beetle research mistake rectified


This May 2014 video says about itself:

The rove beetles are a family (Staphylinidae) of beetles, primarily distinguished by their short elytra that leave more than half of their abdomens exposed. With approximately 58,000 species in thousands of genera, the group is currently recognized as the largest family of beetles. It is an ancient group, with fossil rove beetles known from the Triassic, 200 million years ago, and possibly even earlier if the recently described Leehermania proves to be a member of this family. They are an ecologically and morphologically diverse group of beetleI, and commonly encountered in terrestrial ecosystems.

I did not leave all these inverts together, this video was taken just after I dumped what i’d found into a container to sort through them (I brought a small container with me in the woods).

From the Field Museum in the USA:

Identity crisis for fossil beetle helps rewrite beetle family tree

September 9, 2019

Summary: A tiny fossil beetle, about the size of FDR‘s nose on the US dime, is a totally different species than scientists thought it was, meaning that the beetle family tree needs a rewrite.

There are more different kinds of beetle than just about any other kind of animal — scientists have described about 5,800 different species of mammals, compared with nearly 400,000 species of beetles. Of those 400,000 kinds of beetles, more than 64,000 species are members of the rove beetle family, Staphylinidae. These mostly small earwig-looking insects are found all over the world, and they’ve been around since the time of the dinosaurs. But scientists are still figuring out exactly when rove beetles first evolved. A new study in Systematic Entomology suggests that the fossil beetle species believed to be the oldest rove beetle isn’t a rove beetle at all, meaning the beetle family tree needs a rewrite.

The beetle at the center of this mix-up, about the size of Franklin D. Roosevelt’s nose on the U.S. dime, is Leehermania prorova. When the fossils of Leehermania were first discovered in the 1990s along the Virginia and North Carolina border, they were believed to be the oldest rove beetles ever discovered — by about 50 million years.

Until 2012, the only public information on the fossils was two images, published in 1996 and 2005, but no formal description. Anyone who didn’t have direct access to the fossils of the species could only make guesses about its placement in the tree of life based on those photos.

So, when a formal description of the beetle was finally published, beetle scientists around the world were excited to read it.

“When Leehermania was formally described, and more photos came out, we thought to ourselves ‘that doesn’t look quite right for a staphylinid,'” says Margaret Thayer, a scientist at the Field Museum in Chicago and one of the paper’s nine authors. It didn’t look like the rove beetles that Thayer has spent her career studying.

“I happened to be at the museum when I first read the paper, so I went and looked through the specimens in our collection to compare,” said Alfred Newton, also a Field Museum scientist and paper author. His hunch was that this beetle might be more closely related to Hydroscaphidae, a living family of miniature insects known as skiff beetles, placed in a different suborder from rove beetles.

Across the Atlantic, Martin Fikáček recalled a similar feeling upon comparing the description and photos with the classification of Leehermania as a staphylinid. To Fikáček, a scientist at the National Museum in Prague, the beetle seemed to be a closer fit in the Myxophaga — the suborder that contains skiff beetles. Scientist Chenyang Cai at China’s Nanjing Institute of Geology and Paleontology and several other authors came to the same conclusion.

One of the clues that Leehermania wasn’t really a staphylinid was its mandibles — the pincer-like jaws. “Staphylinids all have exposed mandibles, from at least some angle,” says Newton. “In Leehermania, what were originally interpreted as mandibles are actually maxillary palpi — a different mouthpart structure entirely. The mandibles aren’t exposed here at all, at least from what we can see.”

Another hallmark of staphylinid beetles is their somewhat club-shaped antennae, which start with a narrow base and get wider toward the tip. In Leehermania, the antennae were club-shaped, but the club was more narrowed toward the tip.

Given the hidden mandibles, distinct antennal shape, and other features, including “paratergites” — little plates on the sides of most staphylinid abdomens that are absent in Leehermania — and the shape of the female insects’ genitalia, something wasn’t adding up. Leehermania seemed to be a much better fit in the suborder Myxophaga than in Staphylinidae.

Thanks to the power of the internet, the scientists were able to collaborate freely and quickly across four continents. “The international collaboration that occurred here was really important to the success of the study,” said Shûhei Yamamoto, a Field Museum scientist and paper author who studies staphylinidae and other beetles.

As the group’s hunch turned to a theory, then a study, then a formal analysis, the tests they ran showed Leehermania fitting nicely as a member of the beetle suborder Myxophaga, likely as a sister to the ancestors of today’s skiff beetles. This discovery means that the rove beetle family isn’t yet documented to be as old as scientists thought, but the skiff beetle family is now way older — Leehermania lived 226 million years ago, 100 million years before the next oldest fossil skiff beetle known.

Misclassification of extinct species happens all the time in science, for a variety of reasons.

For one, fossils can be extremely difficult to decipher. Since compression fossils like Leehermania are trapped in a sheet of rock, there is often only one viewing angle, though two in this case: a bird’s-eye-view called “dorsal,” or the top surface, and the “lateral” or side view. Any information about the species has to be gathered from these limited perspectives, so some information on colors, textures, patterns, anatomical details, and of course life-cycle information may be impossible to retrieve. Analysis is even more challenging when your specimens are only 2-3 mm long.

Lack of comparative data also causes problems for researchers. Not only are many characteristics of the insects lost in fossils, but until 2011, the large amount of data used here to test Leehermania’s placement in different families didn’t exist.

“Our analysis made use of a huge data set of morphological characters of beetles gathered for the ‘Beetle Tree of Life’ [BToL] project,” says Thayer. “That project was really crucial to our analysis and provided a framework upon which we were able to analyze Leehermania.” Four authors of the new paper, including Thayer and Newton, were among the authors of the published version of the BToL morphology paper. DNA-based analyses published by the BtoL project and other researchers were also essential to the Leehermania analyses.

Testing and revising the placement of living things in the tree of life is like working on a huge sudoku puzzle with contributors from all over the world. You have methods to figure out where the numbers should go, but if they’re incorrectly placed, you only know — eventually — based on their relationships to the surrounding numbers. If you carry on with the puzzle for too long with an incorrect placement, numbers filled in after the fact might also be incorrect. Revisiting Leehermania’s classification was important to help other researchers avoid using the fossils incorrectly to date analyses of beetles as a whole or identify other beetles as staphylinids based on Leehermania.

For the staphylinid family, losing their oldest ancestor produces new questions about how the family evolved.

“The re-classification of Leehermania means that staphylinids are now 50 million years younger than we thought,” says Fikáček. “But if staphylinids are so much younger, that means that this family evolved into many lineages much more rapidly than we thought they did.” Of course, older staphylinidae fossils are likely to turn up in the future and new analyses will be needed.

At a time in the Earth’s history when life was still recovering after a mass extinction, the appearance of Leehermania and staphylinidae is a testament to how resilient and adaptable beetles can be to diverse, and often harsh, living conditions.

“Throughout history, beetles have survived conditions that other animals have not,” says Fikáček. “As we study these insects, we might reveal some secret to evolutionary success that beetles possess.”

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Were Coelophysis dinosaurs cannibals?


This 14 August 2019 video says about itself:

Was This Dinosaur a Cannibal?

Paleontologists have spent the better part of two decades debating whether Coelophysis ate its own kind. It turns out, the evidence that scientists have had to study in order to answer that question includes some of the strangest and grossest fossils that any expert would ever get to see.

Dinosaur age Triassic tuatara relative discovery


This 5 February 2018 video from Britain says about itself:

New small reptile species that lived 205 million years ago discovered in a quarry in South Wales

Fossils discovered in a quarry in South Wales have been identified as a new small species of reptile that lived 205 million years ago. The species has been called Clevosaurus cambrica, the second part is Latin and refers to the fact that it comes from Wales.

They belong to a new species of Clevosaurus (Gloucester lizard), named in 1939 after Clevum, the Latin name of Gloucester.

The new species, Clevosaurus cambrica lived side by side with a small dinosaur, Pantydraco, and a crocodile-like animal, Terrestrisuchus.

We compared it with other examples of Clevosaurus from places around Bristol and South Gloucestershire, but our new beast is quite different in the arrangement of its teeth. In the Late Triassic period, the foothills of south Wales and southwest England formed an archipelago that was inhabited by small dinosaurs and relatives of the tuatara, a reptilian ‘living fossil’ from New Zealand. The limestone quarries of the region have many caves or fissures that contain sediments filled with bones of small species of reptiles that collapsed at the feet of dinosaurs.

Now, another relative of these reptiles, found far from Wales.

From Midwestern University in the USA:

In the shadow of the dinosaurs

A new sphenodontian from Brazil is the oldest record of the group in Gondwana

August 14, 2019

Research published this Wednesday (August 14th) in Scientific Reports describes Clevosaurus hadroprodon, a new reptile species from Rio Grande do Sul state in southern Brazil. Its fossils remains — jaws and associated skull bones — were collected from Triassic rocks (c. 237-228 million-years old) making it the oldest known fossil of its kind in Gondwana, the southern supercontinent that would eventually become Africa, Antarctica, Australia, India, and South America.

Clevosaurus hadroprodon was a small animal, similar in size with common house geckos. It belongs to the Sphenodontia, a group of lepidosaurs (which also includes snakes, lizards and amphisbaenians), that was very diverse and widespread during the Mesozoic era (the “Age of Dinosaurs”), but today has only one remaining living species in New Zealand. Clevosaurus hadroprodon is the oldest member of the Clevosauridae, a group of small sphenodonts that were the first globally distributed lepidosaurs with fossils from the Late Triassic and Early Jurassic of North America, Europe, Asia, Africa and South America.

The dentition of Clevosaurus hadroprodon is an unexpected mix of primitive and derived teeth. It is the oldest occurrence of the typical fully acrodont dentition (teeth fused to the top of the jaw bones) of sphenodontians, but most of its teeth are relatively simple and blade-like, which differs from other, only slightly younger Clevosaurus species that possess well-developed medial-posteromedial (side-to-side) expansions of the teeth for complex grinding. “However, Clevosaurus hadroprodon also possess a large, blunt, tusk-like tooth in the first tooth position of the both premaxilla (upper jaw) and of dentary (lower jaw). This feature is typically observed only in later sphenodontian lineages” says Annie Schmaltz Hsiou, Associate Professor at the University of São Paulo and head of the study. The name “hadroprodon” is Greek for “larger first tooth” in reference to these tusk-like teeth.

“Clevosaurus hadroprodon is an important discovery because it combines a relatively primitive sphenodontian-type tooth row with the presence of massive tusk-like teeth that were possibly not for feeding, but rather used for mate competition or defense. If correct, this means that non-feeding dental specializations predated changes in the sphenodontian dentition related to feeding strategies. This is a very exciting discovery.” says co-author Randall Nydam, Professor at Midwestern University (US).

In addition to its unique dentition, the authors stress that Clevosaurus hadroprodon also adds to the growing evidence that the early diversification of sphenodontians occurred in the widely separated regions of Gondwana destined to become South American and India. This illustrates the importance of the role of the Gondwanan lepidosaur fauna in our growing understanding of the earliest stages of sphenodontian evolution and the global biogeographic distribution of lepidosaurs.

Permian-Triassic mass extinction, 250,000,000 years ago


This 18 July 2019 video says about itself:

The Siberian Traps: A 250 Million Year Old Crime Scene

The event that killed the dinosaurs 66 million years ago might be the most famous mass extinction ever, but it’s not the only one in Earth’s history, nor is it the worst… not by a long shot.

Permian-Triassic mass extinction, caused by volcanoes?


This 15 September 2015 video from the USA says about itself:

Around 252 millions years ago life on Earth collapsed in a unprecedented fashion as more than 96 percent of marine species and 70 percent of land species disappeared.

The cause of this severe extinction has been a mystery, until now. (Learn more here. MIT researchers have now determined the Siberian Traps erupted at the right time and for the right duration to have been a likely trigger for the end-Permian extinction.

Video produced and edited by Melanie Gonick/MIT

Additional footage and stills: Henrik Svensen, Scott Simper and Seth Burgess

Music sampled from “Out” by Ryan Cross

From the University of Cincinnati in the USA:

New evidence suggests volcanoes caused biggest mass extinction ever

Mercury found in ancient rock around the world supports theory that eruptions caused ‘Great Dying’ 252 million years ago.

April 15, 2019

Researchers say mercury buried in ancient rock provides the strongest evidence yet that volcanoes caused the biggest mass extinction in the history of the Earth.

The extinction 252 million years ago was so dramatic and widespread that scientists call it “the Great Dying.” The catastrophe killed off more than 95 percent of life on Earth over the course of hundreds of thousands of years.

Paleontologists with the University of Cincinnati and the China University of Geosciences said they found a spike in mercury in the geologic record at nearly a dozen sites around the world, which provides persuasive evidence that volcanic eruptions were to blame for this global cataclysm.

The study was published this month in the journal Nature Communications.

The eruptions ignited vast deposits of coal, releasing mercury vapor high into the atmosphere. Eventually, it rained down into the marine sediment around the planet, creating an elemental signature of a catastrophe that would herald the age of dinosaurs.

“Volcanic activities, including emissions of volcanic gases and combustion of organic matter, released abundant mercury to the surface of the Earth,” said lead author Jun Shen, an associate professor at the China University of Geosciences.

The mass extinction occurred at what scientists call the Permian-Triassic Boundary. The mass extinction killed off much of the terrestrial and marine life before the rise of dinosaurs. Some were prehistoric monsters in their own right, such as the ferocious gorgonopsids that looked like a cross between a sabre-toothed tiger and a Komodo dragon.

The eruptions occurred in a volcanic system called the Siberian Traps in what is now central Russia. Many of the eruptions occurred not in cone-shaped volcanoes but through gaping fissures in the ground. The eruptions were frequent and long-lasting and their fury spanned a period of hundreds of thousands of years.

“Typically, when you have large, explosive volcanic eruptions, a lot of mercury is released into the atmosphere,” said Thomas Algeo, a professor of geology in UC’s McMicken College of Arts and Sciences.

“Mercury is a relatively new indicator for researchers. It has become a hot topic for investigating volcanic influences on major events in Earth’s history,” Algeo said.

Researchers use the sharp fossilized teeth of lamprey-like creatures called conodonts to date the rock in which the mercury was deposited. Like most other creatures on the planet, conodonts were decimated by the catastrophe.

The eruptions propelled as much as 3 million cubic kilometers of ash high into the air over this extended period. To put that in perspective, the 1980 eruption of Mount St. Helens in Washington sent just 1 cubic kilometer of ash into the atmosphere, even though ash fell on car windshields as far away as Oklahoma.

In fact, Algeo said, the Siberian Traps eruptions spewed so much material in the air, particularly greenhouse gases, that it warmed the planet by an average of about 10 degrees centigrade.

The warming climate likely would have been one of the biggest culprits in the mass extinction, he said. But acid rain would have spoiled many bodies of water and raised the acidity of the global oceans. And the warmer water would have had more dead zones from a lack of dissolved oxygen.

“We’re often left scratching our heads about what exactly was most harmful. Creatures adapted to colder environments would have been out of luck,” Algeo said. “So my guess is temperature change would be the No. 1 killer. Effects would exacerbated by acidification and other toxins in the environment.”

Stretching over an extended period, eruption after eruption prevented the Earth’s food chain from recovering.

“It’s not necessarily the intensity but the duration that matters,” Algeo said. “The longer this went on, the more pressure was placed on the environment.”

Likewise, the Earth was slow to recover from the disaster because the ongoing disturbances continued to wipe out biodiversity, he said.

Earth has witnessed five known mass extinctions over its 4.5 billion years.

Scientists used another elemental signature — iridium — to pin down the likely cause of the global mass extinction that wiped out the dinosaurs 65 million years ago. They believe an enormous meteor struck what is now Mexico.

The resulting plume of superheated earth blown into the atmosphere rained down material containing iridium that is found in the geologic record around the world.

Shen said the mercury signature provides convincing evidence that the Siberian Traps eruptions were responsible for the catastrophe. Now researchers are trying to pin down the extent of the eruptions and which environmental effects in particular were most responsible for the mass die-off, particularly for land animals and plants.

Shen said the Permian extinction could shed light on how global warming today might lead to the next mass extinction. If global warming, indeed, was responsible for the Permian die-off, what does warming portend for humans and wildlife today?

“The release of carbon into the atmosphere by human beings is similar to the situation in the Late Permian, where abundant carbon was released by the Siberian eruptions,” Shen said.

Algeo said it is cause for concern.

“A majority of biologists believe we’re at the cusp of another mass extinction — the sixth big one. I share that view, too,” Algeo said. “What we should learn is this will be serious business that will harm human interests so we should work to minimize the damage.”

People living in marginal environments such as arid deserts will suffer first. This will lead to more climate refugees around the world.

“We’re likely to see more famine and mass migration in the hardest hit places. It’s a global issue and one we should recognize and proactively deal with. It’s much easier to address these problems before they reach a crisis.”

Swiss Triassic fossil fish, new study


Fossil Fish Eosemionotus diskosomus. Credit: A. López-Arbarello

From the Ludwig-Maximilians-Universität München in Germany:

Paleontology: Diversification after mass extinction

March 1, 2019

A team led by Ludwig-Maximilians-Universitaet (LMU) in Munich paleontologist Adriana López-Arbarello has identified three hitherto unknown fossil fish species in the Swiss Alps, which provide new insights into the diversification of the genus Eosemionotus.

Monte San Giorgio in the Swiss canton of Ticino is one of the most important known sources of marine fossils from the Middle Triassic Period (around 240 million years ago). The new and exquisitely preserved fossil fish specimens, which Dr. Adriana López-Arbarello (a member of the Institute of Paleontology and Geobiology and of the Geobiocenter at LMU) has been studying in collaboration with colleagues based in Switzerland were also discovered in these dolomites and limestones. As the researchers now report in the online journal Palaeontologia Electronica, the specimens represent three previously unknown species of Eosemionotus, a genus of ray-finned fishes. “The largest episode of mass extinction in the history of the Earth took place about 250 million years ago,” as López-Arbarello explains. “Our finds now provide further evidence that after this catastrophic event, the biosphere recovered relatively fast and went through a period of rapid diversification and the emergence of numerous new species during the Middle Triassic.”

The first member of the genus Eosemionotus was discovered in the vicinity of Berlin in 1906, and was named E. vogeli. Almost a century later, in 2004, a second species was described from Monte San Giorgio as E. ceresiensis. Detailed anatomical studies of new material from this locality, carried out by López-Arbarello, have now enabled the recognition of three further species that can be assigned to same genus — E. diskosomus, E. sceltrichensis and E. minutus. All five species are small in size, but they can be clearly distinguished from each other on the basis of the relative proportions of their bodies, the position of the fins, the morphology of the skull, and the disposition of teeth and scales. “These differences indicate that each species was adapted to different ecological niches,” López-Arbarello concludes.

These findings provide new insights into the evolution of the genus. “Our phylogenetic analyses demonstrate that Eosemionotus is the oldest known member of an extinct family within the Order Semionotiformes. Although the Semionotiformes were a species-rich and highly diversified clade during the Mesozoic Era, the order died out in the Cretaceous. Only a few members of its sister group have survived down to the present day, and this ancient lineage is now represented by a single family, the gars,” says López-Arbarello.

Triassic fossil frogs discovery in Arizona, USA


This June 2016 video from the USA says about itself:

In this episode of the Rocks of Utah we explore the Triassic Chinle River Formation. The Rocks of Utah is a YouTube series that explores the unique geology of Utah, and hosted by Benjamin Burger, a geology professor at Utah State University Uintah Basin Campus in Vernal, Utah.

No fossils were collected in this episode, rocks and fossils can not be collected from Dinosaur National Monument, and vertebrate fossils require a permit to collect from Bureau of Land Management Lands in Utah.

From Virginia Tech in the USA:

Oldest frog relative found in North America

February 27, 2019

A team of paleontologists led by Virginia Tech’s Michelle Stocker and Sterling Nesbitt of the Department of Geosciences have identified fossil fragments of what are thought to be the oldest known frogs in North America.

The fossils are comprised of several small pieces of hip bone, called an ilium, from Chinle frogs, a distant long-extinct branch of, but not a direct ancestor of, modern frogs. The fragments are packed into rock and are smaller than a pinky nail. They represent the first known and earliest equatorial remains of a salientian — the group containing living frogs, and their most-closely related fossil relatives — from the Late Triassic, roughly 216 million years ago.

The name of the fossil derives from where they were found, the Chinle Formation of Arizona.

Stocker, an assistant professor of geosciences in the Virginia Tech College of Science, says the fossils, discovered in May 2018, underscore the importance of microfossil collection and analysis for understanding extinct species whose total length is under three feet in length.

“This new find highlights just how much there is still to learn about the Late Triassic ecosystem, and how much we find when we just look a little closer,” Stocker said. “We’re familiar with the charismatic archosaurs from the Chinle Formation, but we know that based on other ecosystems, they should make up a small percentage of the animals that lived together. With this new focus we’re able to fill in a lot of those missing smaller components with new discoveries.”

Coming from multiple individuals, the hip bones are long and hollow, with a hip socket offset rather than centered. The bones of the frogs show how tiny they were: Just a bit over half-an-inch long. “The Chinle frog could fit on the end of your finger,” Stocker added.

Stocker and her team include researchers from Virginia Tech, Arizona’s Petrified Forest National Park, and the University of Florida’s Museum of Natural History, with the findings published today in the online journal Biology Letters. Even though the fossils are part of the Chinle frog family, they are not yet naming the specific fossils.

“We refrain from naming this Chinle frog because we are continuing to process microvertebrate matrix that will likely yield additional skull and postcranial material that has the potential to be even more informative,” Stocker added.

The Chinle frog shares more features with living frogs and Prosalirus, an Early Jurassic frog found in sediments from the present-day Navajo Nation, than to Triadobatrachus, an Early Triassic frog found in modern day Madagascar in Africa. “These are the oldest frogs from near the equator,” Stocker added. “The oldest frogs overall are roughly 250 million years old from Madagascar and Poland, but those specimens are from higher latitudes and not equatorial.”

Added Nesbitt, also an assistant professor of geosciences, “Now we know that tiny frogs were present approximately 215 million years ago from North America, we may be able to find other members of the modern vertebrate communities in the Triassic Period.”

(During the Triassic, the separate continents we recognize today formed the single landmass named Pangaea. Present-day Arizona was located roughly 10 degrees north of the equator.)

The team added this discovery also marks the first time that frog fossils have been found directly with phytosaurs, and … early dinosaurs.

The Virginia Tech team included both undergraduate and graduate students from across the university, using fossils found in the field and dousing additional rock samples repeatedly in water buckets. Further study of the fossils was completed by CT scans. The undergraduates who accompanied Stocker and Nesbitt on the spring 2018 expedition to Arizona included Elizabeth Evans, a major in the School of Performing Arts; Rebecca Hawkins, majoring in the Department of Fish and Wildlife Conservation; and Hector Lopez, majoring in biological sciences.

“Through my internship with Drs. Stocker and Nesbitt in Arizona, I learned firsthand the hard work that paleontologists put into finding fossils,” said Hawkins, a sophomore in the College of Natural Resources and Environment. “Every day you have to brave long treks, heavy loads, scorching heat, and more. But, with just the right combination of patience and luck, you can find something truly amazing that makes the toil worth it, like a tiny frog hip that tells a big story.”

“Our development of methods that recover delicate bones from small-bodied vertebrates enabled this exciting discovery,” said Ben Kligman, a Ph.D. student in Geosciences from Philadelphia, Pennsylvania. “Our aim is to use similar techniques in the Chinle Formation to uncover the early history of other small-bodied animals including lizards, salamanders, turtles, and mammals.”

Funding for the study came from the National Science Foundation, the National Geographic Society, the David B. Jones Foundation, the Petrified Forest Museum Association, and the Friends of Petrified Forest National Park