Formation of sedimentary layers of white clay, Tamilnadu, India

Fossil site for wood fossils, Tamilnadu, India

Fossil site in Kerala, India

Fossil site in Kerala, India

Fossil wood park maintained by geological survey of India at Tamilnadu

Cretaceous fossil sites india

Fossils in rack:-Cyad

Fossils in rack:-echiniderms

Fossils in rack:-Rastellum sp

Pre-historic seabed, Cretaceous period

Remobilization of crustal carbon may dominate volcanic arc emissions

August 14th, 2017 Riffin

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A new analysis suggests that much of the carbon released from volcanic arcs, chains of volcanoes that arise along the tectonic plates of a subduction zone, comes from remobilizing limestone reservoirs in the Earth’s crust. Previous research suggested carbon was sourced from the mantle as a result of the subduction process.

The discovery ultimately impacts the amount of organic carbon scientists believe was buried in the past. Carbon cycling between surface reservoirs and the mantle over geologic history is important because the imbalance greatly influences the amount of total carbon at Earth’s surface. However, the source for carbon from volcanic arc outgassing remained uncertain.

This image depicts results by Mason et al. This material relates to a paper that appeared in the July 21, 2017 issue of Science, published by AAAS. The paper, by E. Mason at University of Cambridge in Cambridge, UK, and colleagues was titled, 'Remobilization of crustal carbon may dominate volcanic arc emissions.' Credit: Carla Schaffer / AAA

This image depicts results by Mason et al. This material relates to a paper that appeared in the July 21, 2017 issue of Science, published by AAAS. The paper, by E. Mason at University of Cambridge in Cambridge, UK, and colleagues was titled, ‘Remobilization of crustal carbon may dominate volcanic arc emissions.’Credit: Carla Schaffer / AAA

Emily Mason and colleagues compiled a global data set of carbon and helium isotopes to determine the origin of the carbon. The data reveal that many volcanic arcs mobilize carbon from large, crustal carbonate platforms — particularly in Italy, the Central American Volcanic Arc, Indonesia, and Papua New Guinea.

In contrast, arcs located in the northern Pacific, such as Japan and Kuril-Kamchatka, release carbon dioxide with an isotope signature indicative of a mantle source.

The recognition of a large amount of crustal carbon in the overall carbon isotope signature requires, from a mass balance consideration, downward revision of how much organic carbon was buried in the past.

Journal Reference:Emily Mason, Marie Edmonds, Alexandra V. Turchyn. Remobilization of crustal carbon may dominate volcanic arc emissions. Science, 2017; 357 (6348): 290 DOI: 10.1126/science.aan5049

American Association for the Advancement of Science. “Crustal limestone platforms feed carbon to many of Earth’s arc volcanoes.” ScienceDaily. ScienceDaily, 20 July 2017. <www.sciencedaily.com/releases/2017/07/170720142223.htm>.
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WFS News: A new species of Tritylodontid found in Japan

August 13th, 2017 Riffin

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 Teeth can reveal a lot, such as how the earliest mammals lived with their neighbors. Researchers have uncovered dozens of fossilized teeth in Kuwajima, Japan and identified this as a new species of tritylodontid, an animal family that links the evolution of mammals from reptiles. This finding suggests that tritylodontids co-existed with some of the earliest mammal species for millions of years, overturning beliefs that mammals wiped out mammal-like reptiles soon after they emerged.

Tritylodontids are the last known family of near-mammalian reptiles, before mammals with features such as advanced hearing evolved.

“Tritylodontids were herbivores with unique sets of teeth which intersect when they bite,” explains study author Hiroshige Matsuoka, based at Kyoto University. “They had pretty much the same features as mammals — for instance they were most likely warm-blooded — but taxonomically speaking they were reptiles, because in their jaws they still had a bone that in mammals is used for hearing.”

Tritylodontids are the last known family of near-mammalian reptiles, before mammals with features such as advanced hearing evolved. Researchers have uncovered dozens of fossilized teeth in Kuwajima, Japan and identified this as a new species of tritylodontid. This suggests that tritylodontids co-existed with some of the earliest mammal species for millions of years. Credit: Seishi Yamamoto/Hiroshige Matsuoka

Tritylodontids are the last known family of near-mammalian reptiles, before mammals with features such as advanced hearing evolved. Researchers have uncovered dozens of fossilized teeth in Kuwajima, Japan and identified this as a new species of tritylodontid. This suggests that tritylodontids co-existed with some of the earliest mammal species for millions of years.
Credit: Seishi Yamamoto/Hiroshige Matsuoka

While excavating a geologic layer from the Cretaceous era in Kuwajima, researchers found fossils of dinosaurs, turtles, lizards, fish, many types of plants, and Mesozoic mammals. Among these were more than 250 tritylodontid teeth, the first to be found in Japan.

Tritylodontids lived in the Jurassic era and proliferated worldwide, but were thought to have died out as herbivorous mammals took over their ecological role in the late Jurassic. “This made sense, because otherwise tritylodontids and the herbivorous mammals would have competed for the same niche,” says Matsuoka.

But according to the team’s finding, trytylodontids seem to have survived at least 30 million years longer than what paleontologists had believed.

“This raises new questions about how tritylodontids and their mammalian neighbors shared or separated ecological roles,” says Matsuoka.

The study is also the first of its kind to depend solely on details from teeth to determine whether the species is new, and also where it sits on the evolutionary tree.

“Usually fossils are identified as a new species only when a relatively complete set of structures like a jaw bone are found. In these cases, characteristics of teeth tend to be described only briefly,” adds Matsuoka. “Tritylodontid teeth have three rows of 2-3 cusps. This time we paid attention to fine details like the size and shape of each cusp. By using this method it should be possible to characterize other species on the evolutionary tree as well.”

“Because fossils of so many diverse families of animals are to be found in Kuwajima, we’d like to keep investigating the site to uncover things not just about individual species, but also about entire ecological dynamics.”

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Journal Reference:Hiroshige Matsuoka, Nao Kusuhashi, Ian J. Corfe. A new Early Cretaceous tritylodontid (Synapsida, Cynodontia, Mammaliamorpha) from the Kuwajima Formation (Tetori Group) of central Japan. Journal of Vertebrate Paleontology, 2016; e1112289 DOI: 10.1080/02724634.2016.1112289
Kyoto University. “Mammal-like reptile survived much longer than thought: Fossils in Japan overturn widely accepted theory about tritylodontid extinction.” ScienceDaily. ScienceDaily, 25 April 2016. <www.sciencedaily.com/releases/2016/04/160425112655.htm>.

The birth and death of a tectonic plate

August 11th, 2017 Riffin

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Several hundred miles off the Pacific Northwest coast, a small tectonic plate called the Juan de Fuca is slowly sliding under the North American continent. This subduction has created a collision zone with the potential to generate huge earthquakes and accompanying tsunamis, which happen when faulted rock abruptly shoves the ocean out of its way.

In fact, this region represents the single greatest geophysical hazard to the continental United States; quakes centered here could register as hundreds of times more damaging than even a big temblor on the San Andreas Fault. Not surprisingly, scientists are interested in understanding as much as they can about the Juan de Fuca Plate.

This microplate is “born” just 300 miles off the coast, at a long range of underwater volcanoes that produce new crust from melt generated deep below. Part of the global mid-ocean ridge system that encircles the planet, these regions generate 70 percent of Earth’s tectonic plates. However, because the chains of volcanoes lie more than a mile beneath the sea surface, scientists know surprisingly little about them.

Ocean-bottom seismometers aboard the R/V Welcoma were deployed in the first year of the Cascadia Initiative. Credit: Dave O'Gorman

Ocean-bottom seismometers aboard the R/V Welcoma were deployed in the first year of the Cascadia Initiative.Credit: Dave O’Gorman

UC Santa Barbara geophysicist Zachary Eilon and his co-author Geoff Abers at Cornell University have conducted new research — using a novel measurement technique — that has revealed a strong signal of seismic attenuation or energy loss at the mid-ocean ridge where the Juan de Fuca Plate is created. The researchers’ attenuation data imply that molten rock here is found even deeper within Earth than scientists had previously thought. This in turn helps scientists understand the processes by which Earth’s tectonic plates are built, as well as the deep plumbing of volcanic systems. The results of the work appear in the journal Science Advances.

“We’ve never had the ability to measure attenuation this way at a mid-ocean ridge before, and the magnitude of the signal tells us that it can’t be explained by shallow structure,” said Eilon, an assistant professor in UCSB’s Department of Earth Science. “Whatever is down there causing all this seismic energy to be lost extends really deep, at least 200 kilometers beneath the surface. That’s unexpected, because we think of the processes that give rise to this — particularly the effect of melting beneath the surface — as being shallow, confined to 60 km or less.”

According to Eilon’s calculations, the narrow strip underneath the mid-ocean ridge, where hot rock wells up to generate the Juan de Fuca Plate, has very high attenuation. In fact, its levels are as high as scientists have seen anywhere on the planet. His findings also suggest that the plate is cooling faster than expected, which affects the friction at the collision zone and the resulting size of any potential megaquake.

Seismic waves begin at an earthquake and radiate away from it. As they disperse, they lose energy. Some of that loss is simply due to spreading out, but another parameter also affects energy loss. Called the quality factor, it essentially describes how squishy Earth is, Eilon said. He used the analogy of a bell to explain how the quality factor works.

“If I were to give you a well-made bell and you were to strike it once, it would ring for a long time,” he explained. “That’s because very little of the energy is actually being lost with each oscillation as the bell rings. That’s very low attenuation, very high quality. But if I give you a poorly made bell and you strike it once, the oscillations will die out very quickly. That’s high attenuation, low quality.”

Eilon looked at the way different frequencies of seismic waves attenuated at different rates. “We looked not only at how much energy is lost but also at the different amounts by which various frequencies are delayed,” he explained. “This new, more robust way of measuring attenuation is a breakthrough that can be applied in other systems around the world.

“Attenuation is a very hard thing to measure, which is why a lot of people ignore it,” Eilon added. “But it gives us a huge amount of new information about Earth’s interior that we wouldn’t have otherwise.”

Next year, Eilon will be part of an international effort to instrument large unexplored swaths of the Pacific with ocean bottom seismometers. Once that data has been collected, he will apply the techniques he developed on the Juan de Fuca in the hope of learning more about what lies beneath the seafloor in the old oceans, where mysterious undulations in Earth’s gravity field have been measured.

“These new ocean bottom data, which are really coming out of technological advances in the instrumentation community, will give us new abilities to see through the ocean floor,” Eilon said. “This is huge because 70 percent of Earth’s surface is covered by water and we’ve largely been blind to it — until now.

“The Pacific Northwest project was an incredibly ambitious community experiment,” he said. “Just imagine the sort of things we’ll find out once we start to put these instruments in other places.”

Source:University of California – Santa Barbara. “The birth and death of a tectonic plate.” ScienceDaily. ScienceDaily, 24 May 2017. <www.sciencedaily.com/releases/2017/05/170524152628.htm>

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WFS News: Maiopatagium furculiferum,First winged mammals from the Jurassic period?

August 10th, 2017 Riffin

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Two 160 million-year-old mammal fossils discovered in China show that the forerunners of mammals in the Jurassic Period evolved to glide and live in trees. With long limbs, long hand and foot fingers, and wing-like membranes for tree-to-tree gliding, Maiopatagium furculiferum and Vilevolodon diplomylos are the oldest known gliders in the long history of early mammals.

The new discoveries suggest that the volant, or flying, way of life evolved among mammalian ancestors 100 million years earlier than the first modern mammal fliers. The fossils are described in two papers published this week in Nature by an international team of scientists from the University of Chicago and Beijing Museum of Natural History.

Photograph of the fossil of gliding mammaliaform Maiopatagium furculiferum (type specimen from Beijing Museum of Natural History BMNH 2940). Credit: Zhe-Xi Luo/UChicago

Photograph of the fossil of gliding mammaliaform Maiopatagium furculiferum (type specimen from Beijing Museum of Natural History BMNH 2940).Credit: Zhe-Xi Luo/UChicago

“These Jurassic mammals are truly ‘the first in glide,'” said Zhe-Xi Luo, PhD, professor of organismal biology and anatomy at the University of Chicago and an author on both papers. “In a way, they got the first wings among all mammals.”

“With every new mammal fossil from the Age of Dinosaurs, we continue to be surprised by how diverse mammalian forerunners were in both feeding and locomotor adaptations. The groundwork for mammals’ successful diversification today appears to have been laid long ago,” he said.

Adaptations in anatomy, lifestyle and diet

The ability to glide in the air is one of the many remarkable adaptations in mammals. Most mammals live on land, but volant mammals, including flying squirrels and bats that flap bird-like wings, made an important transition between land and aerial habitats. The ability to glide between trees allowed the ancient animals to find food that was inaccessible to other land animals. That evolutionary advantage can still be seen among today’s mammals such as flying squirrels in North America and Asia, scaly-tailed gliders of Africa, marsupial sugar gliders of Australia and colugos of Southeast Asia.

The Jurassic Maiopatagium and Vilevolodon are stem mammaliaforms, long-extinct relatives of living mammals. They are haramiyidans, an entirely extinct branch on the mammalian evolutionary tree, but are considered to be among forerunners to modern mammals. Both fossils show the exquisitely fossilized, wing-like skin membranes between their front and back limbs. They also show many skeletal features in their shoulder joints and forelimbs that gave the ancient animals the agility to be capable gliders. Evolutionarily, the two fossils, discovered in the Tiaojishan Formation northeast of Beijing, China, represent the earliest examples of gliding behavior among extinct mammal ancestors.

The two newly discovered creatures also share similar ecology with modern gliders, with some significant differences. Today, the hallmark of most mammal gliders is their herbivorous diet that typically consists of seeds, fruits and other soft parts of flowering plants.

But Maiopatagium and Vilevolodon lived in a Jurassic world where the plant life was dominated by ferns and gymnosperm plants like cycads, gingkoes and conifers — long before flowering plants came to dominate in the Cretaceous Period, and their way of life was also associated with feeding on these entirely different plants. This distinct diet and lifestyle evolved again some 100 million years later among modern mammals, in examples of convergent evolution and ecology.

“It’s amazing that the aerial adaptions occurred so early in the history of mammals,” said study co-author David Grossnickle, a graduate student at the University of Chicago. “Not only did these fossils show exquisite fossilization of gliding membranes, their limb, hand and foot proportion also suggests a new gliding locomotion and behavior.”

Thriving among dinosaurs

Early mammals were once thought to have differences in anatomy from each other, with limited opportunities to inhabit different environments. The new glider fossils from the dinosaur-dominated Jurassic Period, along with numerous other fossils described by Luo and colleagues in the last 10 years, however, provide strong evidence that ancestral mammals adapted to their wide-ranging environments despite competition from dinosaurs.

“Mammals are more diverse in lifestyles than other modern land vertebrates, but we wanted to find out whether early forerunners to mammals had diversified in the same way,” Luo said. “These new fossil gliders are the first winged mammals, and they demonstrate that early mammals did indeed have a wide range of ecological diversity, which means dinosaurs likely did not dominate the Mesozoic landscape as much as previously thought.”

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Journal Reference:Qing-Jin Meng, David M. Grossnickle, Di Liu, Yu-Guang Zhang, April I. Neander, Qiang Ji, Zhe-Xi Luo. New gliding mammaliaforms from the Jurassic. Nature, 2017; DOI: 10.1038/nature23476
University of Chicago Medical Center. “First winged mammals from the Jurassic period discovered: 160-million-year-old fossils suggest a new model of life — gliding — for the forerunners of mammals, in an evolutionary parallel to modern mammal gliders.” ScienceDaily. ScienceDaily, 9 August 2017. <www.sciencedaily.com/releases/2017/08/170809140302.htm>.
 

WFS News: Well-preserved 110 MYO dinosaur found in Canada

August 6th, 2017 Riffin

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AN EXTRAORDINARILY well-preserved 110-million-year-old dinosaur found in a mine pit in Canada now has a name and evidence of a troubled past, researchers said Thursday.

With fossilized skin and scales, the dragon-like creature is actually a new kind of nodosaur, coined Borealopelta markmitchelli, after the museum technician Mark Mitchell who spent more than 7000 hours painstakingly removing rock from around the specimen.

The report in the journal Current Biology described it as “the best-preserved armored dinosaur ever found, and one of the best dinosaur specimens in the world.” The 5.5 meter creature was first discovered in 2011 by a mining machine operator named Shawn Funk, who was working at the Suncor Millennium Mine in Alberta.

This recent handout photograph obtained August 2, 2017, courtesy of the Royal Tyrrell Museum of Paleontology shows the well-preserved head of a 110-million-year-old Borealopelta markmitchelli. Picture: Royal Tyrrell Museum of PaleontologySource:AFP

This recent handout photograph obtained August 2, 2017, courtesy of the Royal Tyrrell Museum of Paleontology shows the well-preserved head of a 110-million-year-old Borealopelta markmitchelli. Picture: Royal Tyrrell Museum of PaleontologySource:AFP

The entire animal would have weighed more than 1,300 kilograms. The portion recovered spans from the snout to the hips.

Unlike most dinosaur specimens, which consist of skeletons or bone fragments, this one is three-dimensional and covered in preserved, scaly skin.

“If you just squint your eyes a bit, you could almost believe it was sleeping,” said lead author Caleb Brown, a scientist at the Royal Tyrrell Museum where the creature is on display.

“It will go down in science history as one of the most beautiful and best preserved dinosaur specimens — the Mona Lisa of dinosaurs.”

By studying its skin, researchers found that this plant-eater, though covered in armor and resembling a walking tank, likely faced a significant threat from meat-eating dinosaurs.

An analysis of the 5.5 metre specimen's form, complete with fully armored skin, suggests the creature had predators, despite the fact that it was the "dinosaur equivalent of a tank," weighing in at more than 1,300 kg. Picture: Royal Tyrrell Museum of PaleontologySource:AFP

An analysis of the 5.5 metre specimen’s form, complete with fully armored skin, suggests the creature had predators, despite the fact that it was the “dinosaur equivalent of a tank,” weighing in at more than 1,300 kg. Picture: Royal Tyrrell Museum of PaleontologySource:AFP

 That’s because it employed a shielding technique known as counter-shading, which is also used by many modern-day animals.

Researchers used chemical analysis of organic compounds in the dinosaur’s scales to reveal the pigmentation pattern of this new genus and species of dinosaur, showing it had reddish-brown pigmented skin with countershading across its the body.

This may have helped it blend in with the environment when approached by a taller predator, researchers say.

But most contemporary animals that have countershading — think deer, zebras or armadillos — are much smaller and more vulnerable as prey, signaling that this nodosaur faced a real struggle to survive.

“Strong predation on a massive, heavily-armored dinosaur illustrates just how dangerous the dinosaur predators of the Cretaceous must have been,” said Brown.

Scientists are continuing to study the animal for clues about its life, including its preserved gut contents to find out what it ate for its last meal.

They believe that when the dinosaur died, it fell into a river and was swept out to sea, where it sank on its back to the ocean floor.

The entire animal dubbed the "dinosaur equivalent of a tank” would have weighed more than 1,300 kilograms.

The entire animal dubbed the “dinosaur equivalent of a tank” would have weighed more than 1,300 kilograms.

At that time, Alberta was as warm as south Florida is today, and rivers and oceans likely spread far further inland than they do now.

The dinosaur was first unveiled to the public in May, but it didn’t yet have a formal name.

Source:http://www.news.com.au,Article AFP

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WFS News: Montsechia vidalii ,First Flower on Earth?

August 3rd, 2017 Riffin

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Three was the magic number for the very first flowering plant. The largest study into their early evolution has concluded that its flowers probably had petal-like tepals and pollen-bearing stamens arranged in layered whorls of three. It bore similarities with magnolias, buttercups and laurels – but was unlike any living flower.

The origin of flowering plants and their rapid conquest of the world’s habitats has been a puzzle for nearly a century and a half. In 1879, Charles Darwin described it as an “abominable mystery” that flowers had evolved so late in the history of life yet were still able to take over from the more ancient seed-bearing pines and cycads.

Today, flowering plants account for nine out of every 10 plants – meaning they far outnumber the once-dominant seed plants like conifers that emerged between 350 and 310 million years ago.

Three-dimensional model of the ancestral flower reconstructed

Three-dimensional model of the ancestral flower reconstructed

Studying their evolutionary roots is tricky, though: the delicacy of flowers means they rarely become fossilised. The oldest so far discovered is the 130- million-year-old aquatic plant Montsechia vidalii unearthed in Spain in 2015. However it is thought that flowering plants first appeared much earlier than this, sometime between 250 and 140 million years ago.

Picking flower traits

To unravel what the very first flower was like, a 36-strong team led by Hervé Sauquet of the University of Paris-South, France, spent six years analysing the anatomical evidence of nearly every type of flowering plant to identify their most ancestral traits.

They calibrated their results with dates derived from molecular analyses and constructed evolutionary trees that modelled the earliest stages in flower evolution.

“We looked at the big bang of flowering plant evolution when they first evolved,” says Sauquet.

They discovered that the first flower probably had 11 or more tepals and stamens, generally grouped in threes and carried both male and female reproductive structures. It was arranged in a unique way unlike any living flower. It’s unclear how large the first flower was, but it may have been just 1 centimetre or less in diameter.

One surprise is how many petal-like tepals the first flower had compared with most living flowers. Reducing their number allowed later flowers to develop a dazzling array of specialised shapes and sizes and consequently diversify along with their animal pollinators into the enormous range of ecosystems  they occupy today. There are some 300,000 living flowering plants.

The findings mean that the living flowers identified as being most ancient, such as Amborella from New Caledonia, and water lilies, are actually quite evolved compared with their ancient ancestors.

Source: Article By James O’Donoghue,www.newscientist.com

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WFS News: Whether sills caused mass extinction?

August 1st, 2017 Riffin

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A study by a researcher in the Syracuse University College of Arts and Sciences offers new clues to what may have triggered the world’s most catastrophic extinction, nearly 252 million years ago.

James Muirhead, a research associate in the Department of Earth Sciences, is the co-author of an article in Nature Communications (Macmillan Publishers Limited, 2017) titled “Initial Pulse of Siberian Traps Sills as the Trigger of the End-Permian Mass Extinction.”

His research involves Seth Burgess, the article’s lead author and a geologist at the U.S. Geological Survey, and Samuel Bowring, the Robert R. Shock Professor of Geology at the Massachusetts Institute of Technology.

Their findings suggest that the formation of intrusive igneous rock, known as sills, sparked a chain of events that brought the Permian geological period to a close. In the process, more than 95 percent of marine species and 70 percent of land species vanished.

Seth Burgess, a geologist at the U.S. Geological Survey, studies a columnar joint in the Siberian Traps. Formed by the cooling of basaltic lava, these massive columns are peppered with orange lichen. Credit: Photo by Scott Simper

Seth Burgess, a geologist at the U.S. Geological Survey, studies a columnar joint in the Siberian Traps. Formed by the cooling of basaltic lava, these massive columns are peppered with orange lichen.Credit: Photo by Scott Simper

“There have been five major mass extinctions, since life originated on Earth more than 600 million years ago,” says Burgess, who works at the nexus of volcanic and tectonic processes. “Most of these events have been blamed, at various times, on volcanic eruptions and asteroids impacts. By reexamining the timing and connection between magmatism [the movement of magma], climate change and extinction, we’ve created a model that explains what triggered the end-Permian mass extinction.”

Central to their study is a large igneous province (LIP) in Russia called the Siberian Traps. Spanning more than 500,000 square miles, this rocky outpost was the site of nearly a million years of epic volcanic activity. Broad, flat volcanoes likely dispelled significant volumes of lava, ashes and gas, while pushing sulfur dioxide, carbon dioxide and methane to dangerous levels in the environment.

But that’s only part of the story.

“Until recently, the relative timing and duration of mass extinctions and LIP volcanism was obscured by age imprecision,” Muirhead says. “Our model is based on new, high-resolution age data that suggests surface lava flows erupted too early to drive mass extinction. Instead, there was a subinterval of magmatism — a shorter, particular part of the LIP — that triggered a cascade of events causing mass extinction.”

The trigger? Extreme heat given off during the formation of sills.

“Heat from sills exposed untapped, gas-rich sediments to contact metamorphism [the process in which rock minerals and texture are changed by exposure to heat and pressure], thus liberating the massive greenhouse gas volumes needed to drive extinction,” Muirhead says. “Our model links the onset of extinction with the initial pulse of sill emplacement. It represents a critical juncture in the evolution of life on Earth.”

There are two ways that magma forms igneous rock. One way is extrusion, in which magma erupts through volcanic craters and cracks in the Earth’s surface; the other is intrusion, whereby magma forces itself between or through existing formations of rock, without reaching the surface. Common types of intrusion are sills, dykes and batholiths.

Sills in Siberia’s Tunguska Basin, where Muirhead’s team carries out most of its research, likely pushed their way through limestone, coal, clastic rocks and evaporates. The mixture of hot, molten rock and hydrocarbon-bearing coals is thought to have set the stage for massive greenhouse gas release and global-scale climate change.

“Sediment composition and the amount of hydrocarbons [petroleum and natural gas] available within these sediments help us understand whether or not an LIP can trigger a mass extinction,” says Burgess, adding that his team’s model may apply to other extinction events coinciding with LIPs. “Mass extinction can take 10,000 years or less — the blink of an eye, by geological standards — but its effects on the evolutionary trajectory of life are still observable today.”

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Journal Reference:S. D. Burgess, J. D. Muirhead, S. A. Bowring. Initial pulse of Siberian Traps sills as the trigger of the end-Permian mass extinction. Nature Communications, 2017; 8 (1) DOI: 10.1038/s41467-017-00083-9
Citation:Syracuse University. “What caused the world’s greatest extinction?.” ScienceDaily. ScienceDaily, 31 July 2017. <www.sciencedaily.com/releases/2017/07/170731090834.htm>.

WFS News: Birgeria americana,Large-mouthed fish was top predator after mass extinction

July 27th, 2017 Riffin

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The 26 cm long fossil preserving the right side of the skull of Birgeria americana. Credit: UZH

The 26 cm long fossil preserving the right side of the skull of Birgeria americana.Credit: UZH

The most catastrophic mass extinction on Earth took place about 252 million years ago — at the boundary between the Permian and Triassic geological periods. Up to 90 percent of the marine species of that time were annihilated. Worldwide biodiversity then recovered in several phases throughout a period of about five million years. Until now, paleontologists have assumed that the first predators at the top of the food chain did not appear until the Middle Triassic epoch about 247 to 235 million years ago.

Unexpected find of a large predatory fish

Swiss and U.S. American researchers led by the Paleontological Institute and Museum of the University of Zurich have discovered the fossil remains of one of the earliest large-sized predatory fishes of the Triassic period: an approximately 1.8-meter-long primitive bony fish with long jaws and sharp teeth. This fish belongs to a previously unknown species called Birgeria americana. This predator occupied the sea that once covered present-day Nevada and the surrounding states already one million years after the mass extinction.

Triassic “Jaws”

In the United States, almost no vertebrate fossils from the Early Triassic epoch (252 to 247 million years ago) have been scientifically described until now. “The surprising find from Elko County in northeastern Nevada is one of the most completely preserved vertebrate remains from this time period ever discovered in the United States,” emphasizes Carlo Romano, lead author of the study. The fossil in question is a 26-centimeter-long partial skull of a fierce predator, as evidenced by three parallel rows of sharp teeth up to 2 centimeters long along the jaw margins, as well as several smaller teeth inside the mouth.

Birgeria hunted similarly to the extant great white shark: the prey fish were pursued and bitten, then swallowed whole. Species of Birgeria existed worldwide. The most recent discovery is the earliest example of a large-sized Birgeria species, about one and a half times longer than geologically older relatives.

Predators appeared earlier than assumed

According to earlier studies, marine food chains were shortened after the mass extinction event and recovered only slowly and stepwise. In addition, researchers assumed that the ancient equatorial regions were too hot for vertebrates to live during the Early Triassic. Finds such as the newly discovered Birgeria species and the fossils of other vertebrates now show that so-called apex predators (animals at the very top of the food chain) already lived early after the mass extinction. The existence of bony fish close to the equator — where Nevada was located during the Early Triassic — indicates that the temperature of the sea was a maximum of 36°C. The eggs of today’s bony fish can no longer develop normally at constant temperatures above 36°C.

“The vertebrates from Nevada show that previous interpretations of past biotic crises and associated global changes were too simplistic,” Carlo Romano says. Despite the severity of the extinctions of that time and intense climatic changes, the food webs were able to redevelop faster than previously assumed.

Citation: Carlo Romano, James F. Jenks, Romain Jattiot, Torsten M. Scheyer, Kevin G. Bylund, Hugo Bucher. Marine Early Triassic Actinopterygii from Elko County (Nevada, USA): implications for the Smithian equatorial vertebrate eclipse. Journal of Paleontology, 2017; 1 DOI: 10.1017/jpa.2017.36

University of Zurich. “Large-mouthed fish was top predator after mass extinction.” ScienceDaily. ScienceDaily, 26 July 2017. <www.sciencedaily.com/releases/2017/07/170726102929.htm>.

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WFS News: Ponomarenkia belmonthensis,300 MYO beetle

July 25th, 2017 Riffin

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He’s Australian, around half a centimetre long, fairly nondescript, 300 million years old, and he’s currently causing astonishment among both entomologists and palaeontologists. The discovery of a beetle from the late Permian period, when even the dinosaurs had not yet appeared on the scene, is throwing a completely new light on the earliest developments in this group of insects. The reconstruction and interpretation of the characteristics of Ponomarenkia belmonthensis was achieved by Prof. Dr Rolf Beutel and Dr Evgeny V. Yan of Friedrich Schiller University Jena (Germany). They have published this discovery together with beetle researcher Dr John Lawrence and Australian geologist Dr Robert Beattie in the current issue of the Journal of Systematic Palaeontology. It was Beattie who discovered the only two known fossilised specimens of the beetle in former marshland in Belmont, Australia.

Habitus photos of †Ponomarenkia belmonthensis sp. nov. A, B, holotype 40278; C, paratype 41618. Scale bars = 1 mm.

Habitus photos of †Ponomarenkia belmonthensis sp. nov. A, B, holotype 40278; C, paratype 41618. Scale bars = 1 mm.

“Beetles, which with nearly 400,000 described species today make up almost one-third of all known organisms, still lived a rather shadowy and cryptic existence in the Permian period,” explains Jena zoologist Beutel. “The fossils known to date have all belonged to an ancestral beetle lineage, with species preferring narrow spaces under bark of coniferous trees. They exhibit a whole series of primitive characteristics, such as wing cases (elytra) that had not yet become completely hardened or a body surface densely covered with small tubercles.”

Line drawings of †Ponomarenkia belmonthensis sp. nov. A, B, holotype; C, D, paratype. Scale bars = 1 mm.

Line drawings of †Ponomarenkia belmonthensis sp. nov. A, B, holotype; C, D, paratype. Scale bars = 1 mm.

Earliest form of the modern beetle

In contrast, the species that has now been discovered, assigned to the newly introduced family Ponomarenkiidae, can be identified as a modern beetle, in spite of its remarkable age. Modern characteristics are the antennae resembling a string of beads, antennal grooves, and the unusually narrow abdomen, tapering to a point. What is more, unlike previously known Permian beetles, the wing cases are completely hardened, the body’s surface is largely smooth, and the thoracic segments responsible for locomotion show modern features, notes insect palaeontologist Yan. In addition, it appears that this little beetle had stopped living under tree bark, the habitat favoured by its contemporaries, and had adopted a much more exposed lifestyle on plants. A significant fact is that, due to its unorthodox combination of ancestral and modern characteristics, this genus does not fit in any of the four suborders of beetles that still exist, which is why Yan and Beutel have given it the nickname Bad Boy. “Ponomarenkia belmonthensis shows above all that the first major events of radiation in the evolution of beetles took place before the Permian-Triassic mass extinction,” says Rolf Beutel. Beetles as a whole survived this dramatic event, which saw the acidification of the seas and major volcanic eruptions, considerably better than most other groups of organisms, presumably because of their terrestrial life style and hardened exoskeleton. However, the Bad Boy ran out of luck, as there are no more traces of its existence in the Mesozoic era.

Name honours eminent palaeontologist

The Jena researchers dedicated the genus and family to Moscow palaeontologist Prof. Alexander G. Ponomarenko. He has had a strong influence on beetle palaeontology for decades and supervised Dr Evgeny V. Yan’s doctorate. Yan obtained his doctorate from the Russian Academy of Sciences, spent five years as a postdoc at the Chinese Academy of Sciences in Nanjing, and since June 2016 he has done research at the Institute of Systematic Zoology and Evolutionary Biology with Phyletic Museum of the University of Jena as a guest researcher funded by the Alexander von Humboldt Foundation. It is Yan’s elaborate reconstructions on the computer that have provided the precise insights into Ponomarenkia belmonthensis.

In the first stage, some 40 photographs were taken of the two specimens, which were available as impressions on stone. “With this series of photographs an accurate 2D reconstruction was possible, with which we were able to correct for deformations in the original fossil. This allowed us to get closer to the actual beetle,” explains Dr Yan. Based on precise drawings and with the help of a special computer program that is also used for animation and computer games, a very informative 3D model was created. “The 3D reconstruction also enables us to draw conclusions about the way the beetle moved and lived,” the palaeontologist adds. He has developed this method of visualisation, as well as the analytical process in which he also includes hypothetical ancestors of the beetle, since his arrival in Jena. “We have already been able to apply this process to three newly discovered ancient beetle species,” Prof. Beutel is happy to report. “In this way, we have made significant steps towards deciphering the earliest stages in the evolution of an extremely successful genus of animals.”

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Citation:Friedrich-Schiller-Universitaet Jena. “300 million-year-old ‘modern’ beetle from Australia reconstructed.” ScienceDaily. ScienceDaily, 24 July 2017. <www.sciencedaily.com/releases/2017/07/170724105041.htm>

WFS News: Boy trips, falls and discovers million-year-old Ice Age fossil

July 20th, 2017 Riffin

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Researchers have their hands on a rare fossil from the Pleistocene era thanks to a 10-year-old’s clumsiness.Jude Sparks said he literally fell on the 1.2-million-year-old skull of a stegomastodon — a massive prehistoric creature with tusks like an elephant — while on a hike with his parents on the desert outskirts of his neighborhood in Las Cruces, New Mexico.

“I was running farther up and I tripped on part of the tusk,” Sparks said in a statement from New Mexico State University, where researchers are studying the find. “My face landed next to the bottom jaw. I looked farther up and there was another tusk.”

Jude Sparks, 10, said he literally fell on this 1.2-million-year-old stegomastodon skull on the outskirts of his neighborhood in Las Cruces, New Mexico. NEW MEXICO STATE UNIVERSITY

Jude Sparks, 10, said he literally fell on this 1.2-million-year-old stegomastodon skull on the outskirts of his neighborhood in Las Cruces, New Mexico. NEW MEXICO STATE UNIVERSITY

The stegomastodon is one of three species of proboscideans that inhabited the ancient Rio Grande Valley, and is believed to be an ancestor to modern-day elephants.Sparks’ parents contacted biologist Peter Houde, a professor at New Mexico State University, after hearing he had discovered a similar fossil in a quarry south of campus, the university said.

The fossil was found on private land, and it took several months to get permission to excavate from the property owner. In New Mexico, the law stipulates that vertebrate fossils found on private land belong to the landowner. Here, the property owner asked that the precise site remain confidential, according to the university.

The Sparks family eventually joined with Houde and his students to excavate the skull, a process that took one week.The large skull is deceptively delicate, and the only thing holding it together was the sediment around it, Houde said.

“When the sediments are removed from the sides of [the bones], they start to fall apart immediately and literally fall into tiny, tiny bits. It has to be done carefully by somebody who knows how to go about doing it. It is a very deliberate process that takes a little bit of time,” he said.

The team applied chemical hardeners to the fossil, mimicking the bone strength provided by protein, to keep it intact. Once dug from the ground, the fossil was coated in plaster and supported by wood braces for transport to New Mexico State University’s Vertebrate Museum, where it now lives.

Peter Houde of New Mexico State University poses with the tusk and mandible of a stegomastodon in the university's Vertebrate Museum. NMSU/ANDRES LEIGHTON

Peter Houde of New Mexico State University poses with the tusk and mandible of a stegomastodon in the university’s Vertebrate Museum. NMSU/ANDRES LEIGHTON

“We have the unique opportunity to really compare what the animal looks like [on] a much larger complete scale and compare it with others,” Houde told CBS Albuquerque affiliate KRQE, adding that it’s extremely rare to find a nearly intact skull of a mammal dating back to the Ice Age.

The process to reconstruct the skull, jaw and tusks is likely to take years to complete, Houde said.

“I have every hope and expectation that this specimen will ultimately end up on exhibit and this little boy will be able to show his friends and even his own children, look what I found right here in Las Cruces,” he said.

Source: Article by SHANIKA GUNARATNA CBS NEWS July 19, 2017

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