WFS News: Moabosaurus discovered in Utah’s ‘gold mine’

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The Moabosaurus discovery was published this week by the University of Michigan’s Contributions from the Museum of Paleontology. The paper, authored by three Brigham Young University researchers and a BYU graduate at Auburn University, profiles Moabosaurus, a 125-million-year-old dinosaur whose skeleton was assembled using bones extracted from the Dalton Wells Quarry, near Arches National Park.

BYU geology professor and lead author Brooks Britt explained that in analyzing dinosaur bones, he and colleagues rely on constant comparisons with other related specimens. If there are enough distinguishing features to make it unique, it’s new.

“It’s like looking at a piece of a car,” Britt said. “You can look at it and say it belongs to a Ford sedan, but it’s not exactly a Focus or a Fusion or a Fiesta. We do the same with dinosaurs.”

BYU researcher Brooks Britt is with the newly discovered Moabosaurus, on display at BYU's Museum of Paleontology. Credit: Jaren Wilkey, BYU

BYU researcher Brooks Britt is with the newly discovered Moabosaurus, on display at BYU’s Museum of Paleontology.
Credit: Jaren Wilkey, BYU

Moabosaurus belongs to a group of herbivorous dinosaurs known as sauropods, which includes giants such as Brontosaurus and Brachiosaurus, who had long necks and pillar-like legs. Moabosaurus is most closely related to species found in Spain and Tanzania, which tells researchers that during its time, there were still intermittent physical connections between Europe, Africa and North America.

Moabosaurus lived in Utah before it resembled the desert we know — when it was filled with large trees, plentiful streams, lakes and dinosaurs. “We always think of Moab in terms of tourism and outdoor activities, but a paleontologist thinks of Moab as a gold mine for dinosaur bones,” Britt said.

In naming the species, Britt and his team, which included BYU Museum of Paleontology curator Rod Scheetz and biology professor Michael Whiting, decided to pay tribute to that gold mine. “We’re honoring the city of Moab and the State of Utah because they were so supportive of our excavation efforts over the decades it’s taken us to pull the animal out of the ground,” Britt said, referencing the digs that began when he was a BYU geology student in the late ’70s.

Credit: Brigham Young University

    Credit: Brigham Young University

A previous study indicates that a large number of Moabosaurus and other dinosaurs died in a severe drought. Survivors trampled their fallen companions’ bodies, crushing their bones. After the drought ended, streams eroded the land, and transported the bones a short distance, where they were again trampled. Meanwhile, insects in the soils fed on the bones, leaving behind tell-tale burrow marks.

“We’re lucky to get anything out of this site,” Britt said. “Most bones we find are fragmentary, so only a small percentage of them are usable. And that’s why it took so long to get this animal put together: we had to collect huge numbers of bones in order to get enough that were complete.”

BYU has a legacy of collecting dinosaurs that started in the early 1960s, and Britt and colleagues are continuing their excavation efforts in eastern Utah. Moabosaurus now joins a range of other findings currently on display at BYU’s Museum of Paleontology — though, until its placard is updated, it’s identified as “Not yet named” (pronunciation: NOT-yet-NAIM-ed).

“Sure, we could find bones at other places in the world, but we find so many right here in Utah,” Britt said. “You don’t have to travel the world to discover new animals.”

Journal Reference:Britt, Brooks B.; Scheets, Rodney D.; Whiting, Michael F.; Wilhite, D. Ray. MOABOSAURUS UTAHENSIS, N. Gen., N. SP., A New Sauropod From The Early Cretaceous (Aptian) of North America. Contributions from the Museum of Paleontology, 2017 [link] andBrigham Young University. “Moabosaurus discovered in Utah’s ‘gold mine’.” ScienceDaily. ScienceDaily, 13 April 2017. <www.sciencedaily.com

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WFS News: Evidence of Earthquakes recorded on fossils

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The Cascadia subduction zone (CSZ) has captured major attention from paleoseismologists due to evidence from several large (magnitude 8-9) earthquakes preserved in coastal salt marshes. Stratigraphic records are proving to be useful for learning about the CSZ’s past, and microfossils may provide more answers about large ancient earthquakes. They may also allow modelers to learn more about potential major hazards related to earthquakes in the area, which would contribute to public preparedness for such events.

Over the past three decades, researchers have found stratigraphic evidence of subsidence occurring during earthquakes beneath the salt marshes of Humboldt Bay, California, USA, at the southern end of the CSZ. J. Scott Padgett of the University of Rhode Island uses analysis of fossil foraminifera to estimate this subsidence at Arcata Bay, just north of Humboldt Bay. He will report on his research on 2 November at the Geological Society of America’s Annual Meeting in Baltimore, Maryland, USA.

mocrofossils

    microfossils

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Padgett notes, “Previous investigations were able to provide estimates of subsidence with large errors, which are only so helpful to the modelers.” More recently, researchers started using an improved analysis on the microfossil data in Oregon, and were able to generate subsidence estimates with smaller errors. Their refined results enabled modelers to produce earthquake models that are more consistent with observed subsidence measurements seen in today’s instrumented earthquakes.

Similar work is being done at Jacoby Creek, a small coastal drainage that flows into northern Arcata Bay. There, researchers have found three sharp contacts between salt marsh peat and intertidal mud dating back over the past 2,000 years. Radiocarbon ages of plant macrofossils at the top of the buried peats are 195, 1280, and 1710 years old. These new ages provide tighter constraints on the timing of past earthquakes and subsidence at the southern end of the CSZ.

Padgett says there are several lines of evidence that support their results and interpretation at Jacoby Creek. “These include the sharp mud-over-peat contacts that are laterally continuous over 5 kilometers, changes in fossil foraminifera assemblages across the buried peat contacts, long-lasting submergence also derived from fossil foraminifera records, and radiocarbon ages of plant macrofossils taken from buried peat deposits that are consistent with other southern Cascadia earthquake chronologies derived from buried peat and tsunami deposits.”

Citation:Geological Society of America. “Earthquakes recorded through fossils.”

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WFS News: How the darkness and the cold killed the dinosaurs

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Sixty six million years ago, the sudden extinction of the dinosaurs started the ascent of the mammals, ultimately resulting in humankind’s reign on Earth. Climate scientists now reconstructed how tiny droplets of sulfuric acid formed high up in the air after the well-known impact of a large asteroid and blocking the sunlight for several years, had a profound influence on life on Earth. Plants died, and death spread through the food web. Previous theories focused on the shorter-lived dust ejected by the impact. The new computer simulations show that the droplets resulted in long-lasting cooling, a likely contributor to the death of land-living dinosaurs. An additional kill mechanism might have been a vigorous mixing of the oceans, caused by the surface cooling, severely disturbing marine ecosystems.

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asteroid impact.

asteroid impact.

“The big chill following the impact of the asteroid that formed the Chicxulub crater in Mexico is a turning point in Earth history,” says Julia Brugger from the Potsdam Institute for Climate Impact Research (PIK), lead author of the study to be published in the Geophysical Research Letters. “We can now contribute new insights for understanding the much debated ultimate cause for the demise of the dinosaurs at the end of the Cretaceous era.” To investigate the phenomenon, the scientists for the first time used a specific kind of computer simulation normally applied in different contexts, a climate model coupling atmosphere, ocean and sea ice. They build on research showing that sulfur- bearing gases that evaporated from the violent asteroid impact on our planet’s surface were the main factor for blocking the sunlight and cooling down Earth.

In the tropics, annual mean temperature fell from 27 to 5 degrees Celsius

“It became cold, I mean, really cold,” says Brugger. Global annual mean surface air temperature dropped by at least 26 degrees Celsius. The dinosaurs were used to living in a lush climate. After the asteroid’s impact, the annual average temperature was below freezing point for about 3 years. Evidently, the ice caps expanded. Even in the tropics, annual mean temperatures went from 27 degrees to mere 5 degrees. “The long-term cooling caused by the sulfate aerosols was much more important for the mass extinction than the dust that stays in the atmosphere for only a relatively short time. It was also more important than local events like the extreme heat close to the impact, wildfires or tsunamis,” says co-author Georg Feulner who leads the research team at PIK. It took the climate about 30 years to recover, the scientists found.

In addition to this, ocean circulation became disturbed. Surface waters cooled down, thereby becoming denser and hence heavier. While these cooler water masses sank into the depths, warmer water from deeper ocean layers rose to the surface, carrying nutrients that likely led to massive blooms of algae, the scientists argue. It is conceivable that these algal blooms produced toxic substances, further affecting life at the coasts. Yet in any case, marine ecosystems were severely shaken up, and this likely contributed to the extinction of species in the oceans, like the ammonites.

“It illustrates how important the climate is for all lifeforms on our planet”

The dinosaurs, until then the masters of Earth, made space for the rise of the mammals, and eventually humankind. The study of Earth’s past also shows that efforts to study future threats by asteroids have more than just academic interest. “It is fascinating to see how evolution is partly driven by an accident like an asteroid’s impact — mass extinctions show that life on Earth is vulnerable,” says Feulner. “It also illustrates how important the climate is for all lifeforms on our planet. Ironically today, the most immediate threat is not from natural cooling but from human-made global warming.”

Citation:Potsdam Institute for Climate Impact Research (PIK). “How the darkness and the cold killed the dinosaurs.” ScienceDaily. ScienceDaily, 13 January 2017. www.sciencedaily.com/releases/2017/01/170113133043.htm.

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WFS News: oldest known member of the phytosaurs found in China

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The skeleton of a small, short-snouted reptile found in China was recently identified as the oldest known member of the phytosaurs — an extinct group of large, semi-aquatic reptiles that superficially resembled the distantly-related crocodylians and lived during the Triassic Period, approximately 250 million years ago to 200 million years ago.

Holotype specimen of Diandongosuchus fuyuanensis (ZMNH M8770), showing relevant cranial features shared with Phytosauria.

Holotype specimen of Diandongosuchus fuyuanensis (ZMNH M8770), showing relevant cranial features shared with Phytosauria.

Virginia Tech researchers led the team that re-evaluated and re-classified the animal, Diandongosuchus fuyuanensis, which had previously been labeled as a poposauroid, a group of animals more closely related to crocodiles.

The shape of the animal’s head, shoulder, and skeleton bones is what gave away the animal’s linkage to the phytosaurs, according to Michelle Stocker, lead author and assistant professor of geosciences in the College of Science. After seeing a photo of the fossil in a paper published in 2012, she and other co-authors met in China in 2015 to re-examine the bones. Their findings were published in Scientific Reports April 10.

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Holotype specimen of Diandongosuchus fuyuanensis (ZMNH M8770) in ventral view with relevant postcranial features shared with Phytosauria (in green) and elements with features not found in other phytosaurs (in orange).

Holotype specimen of Diandongosuchus fuyuanensis (ZMNH M8770) in ventral view with relevant postcranial features shared with Phytosauria (in green) and elements with features not found in other phytosaurs (in orange).

The fossil, which is older than other phytosaur fossils by about 5 million years, fills a critical gap in scientists’ understanding of how the animal evolved. The short snout and small body size suggest that the features the species is most known for — a long snout and large body size — evolved later than previously thought. A long snout is useful for predatory endeavors like reaching, snapping, and biting.

“So much of our study of the fossil record is about filling in the gaps in our knowledge of how animals came to look as they do or live where they are, and Diandongosuchus does that for phytosaurs. We’re never done filling in those gaps,” said Stocker.

“Early members of these Triassic reptile lineages are appearing where they’ve been predicted for years. Now we have the fossils,” said Nesbitt.

Courtesy: www.sciencedaily.com/2017,Riffin T Sajeev,Russel T Sajeev

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WFS News: 3-D map of Earth’s interior

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Because of Earth’s layered composition, scientists have often compared the basic arrangement of its interior to that of an onion. There’s the familiar thin crust of continents and ocean floors; the thick mantle of hot, semisolid rock; the molten metal outer core; and the solid iron inner core.

But unlike an onion, peeling back Earth’s layers to better explore planetary dynamics isn’t an option, forcing scientists to make educated guesses about our planet’s inner life based on surface-level observations. Clever imaging techniques devised by computational scientists, however, offer the promise of illuminating Earth’s subterranean secrets.

Using advanced modeling and simulation, seismic data generated by earthquakes, and one of the world’s fastest supercomputers, a team led by Jeroen Tromp of Princeton University is creating a detailed 3-D picture of Earth’s interior. Currently, the team is focused on imaging the entire globe from the surface to the core-mantle boundary, a depth of 1,800 miles.

This visualization is the first global tomographic model constructed based on adjoint tomography, an iterative full-waveform inversion technique. The model is a result of data from 253 earthquakes and 15 conjugate gradient iterations with transverse isotropy confined to the upper mantle. Credit: David Pugmire, ORNL

This visualization is the first global tomographic model constructed based on adjoint tomography, an iterative full-waveform inversion technique. The model is a result of data from 253 earthquakes and 15 conjugate gradient iterations with transverse isotropy confined to the upper mantle.
Credit: David Pugmire, ORNL

These high-fidelity simulations add context to ongoing debates related to Earth’s geologic history and dynamics, bringing prominent features like tectonic plates, magma plumes, and hotspots into view. In 2016, the team released its first-generation global model. Created using data from 253 earthquakes captured by seismograms scattered around the world, the team’s model is notable for its global scope and high scalability.

“This is the first global seismic model where no approximations — other than the chosen numerical method — were used to simulate how seismic waves travel through Earth and how they sense heterogeneities,” said Ebru Bozdag, a coprincipal investigator of the project and an assistant professor of geophysics at the University of Nice Sophia Antipolis. “That’s a milestone for the seismology community. For the first time, we showed people the value and feasibility of running these kinds of tools for global seismic imaging.”

The project’s genesis can be traced to a seismic imaging theory first proposed in the 1980s. To fill in gaps within seismic data maps, the theory posited a method called adjoint tomography, an iterative full-waveform inversion technique. This technique leverages more information than competing methods, using forward waves that travel from the quake’s origin to the seismic receiver and adjoint waves, which are mathematically derived waves that travel from the receiver to the quake.

The problem with testing this theory? “You need really big computers to do this,” Bozdag said, “because both forward and adjoint wave simulations are performed in 3-D numerically.”

In 2012, just such a machine arrived in the form of the Titan supercomputer, a 27-petaflop Cray XK7 managed by the US Department of Energy’s (DOE’s) Oak Ridge Leadership Computing Facility (OLCF), a DOE Office of Science User Facility located at DOE’s Oak Ridge National Laboratory. After trying out its method on smaller machines, Tromp’s team gained access to Titan in 2013 through the Innovative and Novel Computational Impact on Theory and Experiment, or INCITE, program.

Working with OLCF staff, the team continues to push the limits of computational seismology to deeper depths.

Stitching together seismic slices

When an earthquake strikes, the release of energy creates seismic waves that often wreak havoc for life at the surface. Those same waves, however, present an opportunity for scientists to peer into the subsurface by measuring vibrations passing through Earth.

As seismic waves travel, seismograms can detect variations in their speed. These changes provide clues about the composition, density, and temperature of the medium the wave is passing through. For example, waves move slower when passing through hot magma, such as mantle plumes and hotspots, than they do when passing through colder subduction zones, locations where one tectonic plate slides beneath another.

Each seismogram represents a narrow slice of the planet’s interior. By stitching many seismograms together, researchers can produce a 3-D global image, capturing everything from magma plumes feeding the Ring of Fire, to Yellowstone’s hotspots, to subducted plates under New Zealand.

This process, called seismic tomography, works in a manner similar to imaging techniques employed in medicine, where 2-D x-ray images taken from many perspectives are combined to create 3-D images of areas inside the body.

In the past, seismic tomography techniques have been limited in the amount of seismic data they can use. Traditional methods forced researchers to make approximations in their wave simulations and restrict observational data to major seismic phases only. Adjoint tomography based on 3-D numerical simulations employed by Tromp’s team isn’t constrained in this way. “We can use the entire data — anything and everything,” Bozdag said.

Running its GPU version of the SPECFEM3D_GLOBE code, Tromp’s team used Titan to apply full-waveform inversion at a global scale. The team then compared these “synthetic seismograms” with observed seismic data supplied by the Incorporated Research Institutions for Seismology (IRIS), calculating the difference and feeding that information back into the model for further optimization. Each repetition of this process improves global models.

“This is what we call the adjoint tomography workflow, and at a global scale it requires a supercomputer like Titan to be executed in reasonable timeframe,” Bozdag said. “For our first-generation model, we completed 15 iterations, which is actually a small number for these kinds of problems. Despite the small number of iterations, our enhanced global model shows the power of our approach. This is just the beginning, however.”

Automating to augment

For its initial global model, Tromp’s team selected earthquake events that registered between 5.8 and 7 on the Richter scale — a standard for measuring earthquake intensity. That range can be extended slightly to include more than 6,000 earthquakes in the IRIS database — about 20 times the amount of data used in the original model.

Getting the most out of all the available data requires a robust automated workflow capable of accelerating the team’s iterative process. Collaborating with OLCF staff, Tromp’s team has made progress toward this goal.

For the team’s first-generation model, Bozdag carried out each step of the workflow manually, taking about a month to complete one model update. Team members Matthieu Lefebvre, Wenjie Lei, and Youyi Ruan of Princeton University and the OLCF’s Judy Hill developed new automated workflow processes that hold the promise of reducing that cycle to a matter of days.

“Automation will really make it more efficient, and it will also reduce human error, which is pretty easy to introduce,” Bozdag said.

Additional support from OLCF staff has contributed to the efficient use and accessibility of project data. Early in the project’s life, Tromp’s team worked with the OLCF’s Norbert Podhorszki to improve data movement and flexibility. The end result, called Adaptable Seismic Data Format (ASDF), leverages the Adaptable I/O System (ADIOS) parallel library and gives Tromp’s team a superior file format to record, reproduce, and analyze data on large-scale parallel computing resources.

In addition, the OLCF’s David Pugmire helped the team implement in situ visualization tools. These tools enabled team members to check their work more easily from local workstations by allowing visualizations to be produced in conjunction with simulation on Titan, eliminating the need for costly file transfers.

“Sometimes the devil is in the details, so you really need to be careful and know what you’re looking at,” Bozdag said. “David’s visualization tools help us to investigate our models and see what is there and what is not.”

With visualization, the magnitude of the team’s project comes to light. The billion-year cycle of molten rock rising from the core-mantle boundary and falling from the crust — not unlike the motion of globules in a lava lamp — takes form, as do other geologic features of interest.

At this stage, the resolution of the team’s global model is becoming advanced enough to inform continental studies, particularly in regions with dense data coverage. Making it useful at the regional level or smaller, such as the mantle activity beneath Southern California or the earthquake-prone crust of Istanbul, will require additional work.

“Most global models in seismology agree at large scales but differ from each other significantly at the smaller scales,” Bozdag said. “That’s why it’s crucial to have a more accurate image of Earth’s interior. Creating high-resolution images of the mantle will allow us to contribute to these discussions.”

Digging deeper

To improve accuracy and resolution further, Tromp’s team is experimenting with model parameters under its most recent INCITE allocation. For example, the team’s second-generation model will introduce anisotropic inversions, which are calculations that better capture the differing orientations and movement of rock in the mantle. This new information should give scientists a clearer picture of mantle flow, composition, and crust-mantle interactions.

Additionally, team members Dimitri Komatitsch of Aix-Marseille University in France and Daniel Peter of King Abdullah University in Saudi Arabia are leading efforts to update SPECFEM3D_GLOBE to incorporate capabilities such as the simulation of higher-frequency seismic waves. The frequency of a seismic wave, measured in Hertz, is equivalent to the number of waves passing through a fixed point in one second. For instance, the current minimum frequency used in the team’s simulation is about 0.05 hertz (1 wave per 20 seconds), but Bozdag said the team would also like to incorporate seismic waves of up to 1 hertz (1 wave per second). This would allow the team to model finer details in Earth’s mantle and even begin mapping Earth’s core.

To make this leap, Tromp’s team is preparing for Summit, the OLCF’s next-generation supercomputer. Set to arrive in 2018, Summit will provide at least five times the computing power of Titan. As part of the OLCF’s Center for Accelerated Application Readiness, Tromp’s team is working with OLCF staff to take advantage of Summit’s computing power upon arrival.

“With Summit, we will be able to image the entire globe from crust all the way down to Earth’s center, including the core,” Bozdag said. “Our methods are expensive — we need a supercomputer to carry them out — but our results show that these expenses are justified, even necessary.”

Citation:DOE/Oak Ridge National Laboratory. “A seismic mapping milestone: Team produces 3-D map of Earth’s interior.” ScienceDaily. ScienceDaily, 28 March 2017. <www.sciencedaily.com/releases/2017/03/170328135508.htm

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WFS News: Kimberley fossil tracks are Australia’s ‘Jurassic Park’

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Scientists have described a remarkable collection of dinosaur tracks on beaches in the Kimberley region of Western Australia.

More than 20 different types of fossil footmarks have been captured in sandstone rock.Some are over 1.5m in size, recording the movement of sauropods – the giant beasts with long necks and tails.

The trackways, many only visible at low tide, were “globally unparalleled”, claimed the lead scientist involved.Steve Salisbury called the 25km-long coastline collection Australia’s own Jurassic Park.

 

 

 

 

QUEENSLAND UNIVERSITY / JAMES COOK UNIVERSITY

                             Australia’s own Jurassic Park 

          

 
 Australia's own Jurassic Park.The biggest sauropod prints are over a metre long 

Australia’s own Jurassic Park.The biggest sauropod prints are over a metre long@WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

“This is the most diverse dinosaur track fauna we’ve ever recorded,” he told BBC News.

“In this time slice (127 and 140 million years ago) in Australia, we’ve got no other record – there’s virtually no other fossils from any part of the continent. This is only window, and what we see is truly amazing.

“Twenty-one different types. There are about six different types of tracks for meat-eating dinosaurs; about the same number for sauropod dinosaurs; about four different types of ornithopod dinosaur tracks – so, two-legged plant-eaters – and really exciting, I think, are six types of armoured dinosaur tracks, including stegosaurs, which we’ve never seen before in Australia.”

Australian first: Stegosaurs had angular bony plates protruding from their backs

Australian first: Stegosaurs had angular bony plates protruding from their backs

The researcher put together a team from Queensland University and James Cook University to investigate the footprints after being invited to do so by area’s Goolarabooloo Traditional Custodians.

Back in 2008, the aboriginal people of Western Australia’s Kimberley regi

on had been concerned about the possible development of a liquid natural gas facility.

They asked Dr Salisbury to document the beach prints as part of their campaign of opposition.

The scientist said the indigenous people had long referred to the markings in their oral history – probably for thousands of years.

“They form part of a song cycle – they relate to a creation mythology, and specifically the tracks show the journey of a creation being called Marala – the emu man. “Wherever he went he left behind three-toed tracks that now we recognise as the tracks of meat-eating dinosaurs.”

Dr Salisbury’s team spent more than 400 hours detailing the prints between 2011 to 2016.

Thousands of tracks are recorded at 48 discrete sites centred on Walmadany (James Price Point) on the Dampier Peninsula.

The scientists examined and measured the depressions using three-dimensional photogrammetry, which builds accurate models of the subjects under investigation by taking pictures from various angles.

For a good many, they took silicone peels from which to make casts that could then be shown in museums.

Most of Australia’s dinosaur fossils come from the eastern side of the continent, and are between 115 and 90 million years old.

The research has been published as the 2016 Memoir of the Society of Vertebrate Paleontology.

Courtesy: Article by 

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Paleozoic echinoderm hangover: Waking up in the Triassic

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The end-Paleozoic witnessed the most devastating mass extinction in Earth’s history so far, killing the majority of species and profoundly shaping the evolutionary history of the survivors. Echinoderms are among the marine invertebrates that suffered the most severe losses at the end-Permian extinction.

At least that was the consensus until a team of European paleontologists — Ben Thuy, Hans Hagdorn, and Andy S. Gale — cast a critical eye on some poorly studied Triassic echinoderm fossils. The fossils turned out to belong to groups that supposedly went extinct by the end of the Paleozoic.

These are paleozoic hangover asterozoans. Specimen repositories: MHI = Muschelkalkmuseum Ingelfingen; MnhnL = Natural History Museum Luxembourg. Figure courtesy B. Thuy et al., copyright The Geological Society of America, 2017. Credit: Figure courtesy B. Thuy et al., copyright The Geological Society of America, 2017.

These are paleozoic hangover asterozoans. Specimen repositories: MHI = Muschelkalkmuseum Ingelfingen; MnhnL = Natural History Museum Luxembourg. Figure courtesy B. Thuy et al., copyright The Geological Society of America, 2017.
Credit: Figure courtesy B. Thuy et al., copyright The Geological Society of America, 2017.

Some ancient echinoids, ophiuroids, and asteroids had slipped the bottleneck and coexisted with the ancestors of modern-day sea urchins, brittle stars, sand dollars, and relatives, for many millions of years. These echinoderm hangovers occurred almost worldwide and had spread into a wide range of paleo-environments by the late Triassic.

This discovery challenges the fundamentals of echinoderm evolution with respect to end-Permian survival and sheds new light on the early evolution of the modern clades, in particular on Triassic ghost lineages of the crown-group look-alikes of the Paleozoic hangovers.

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Journal Ref: Andy S. Gale et al. Paleozoic echinoderm hangovers: Waking up in the Triassic. Geology, March 2017 DOI: 10.1130/G38909.1

Courtesy:ScienceDaily. ScienceDaily, 16 March 2017.

WFS News: Paleontologists find fossil relative of Ginkgo biloba

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A discovery of well-preserved fossil plants by paleontologists from the United States, China, Japan, Russia and Mongolia has allowed researchers to identify a distant relative of the living plant Ginkgo biloba.

The find helps scientists better understand the evolution and diversity of ancient seed plants.

The fossils, from the species Umaltolepis mongoliensis, date back to the early Cretaceous Period (some 100-125 million years ago). Scientists discovered the fossils in ancient peat deposits at the Tevshiin Govi mine in the steppes of central Mongolia. Results of the research, supported by the National Science Foundation (NSF), are published in this week’s issue of the journal Proceedings of the National Academy of Sciences (PNAS).

“The stems and leaves are similar to the ginkgo tree, but the seeds, and especially the structures they are born in, are unlike any other known plant, living or extinct,” says scientist Patrick Herendeen of the Chicago Botanic Garden, co-author of the PNAS paper. “Finding something like this does not happen very often.”

Reconstruction of the ancient, dinosaur-era relative of today's Ginkgo biloba plant. Credit: Fabiany Herrera & Patrick Herendeen

      Reconstruction of the ancient, dinosaur-era relative of today’s Ginkgo biloba plant.
                                          Credit: Fabiany Herrera & Patrick Herendeen

Scientists had previously uncovered fossils of U. mongoliensis,but those were in poor condition, making them difficult to study. Hundreds of better-preserved new fossils show that features of the stems and leaves are similar to those of living ginkgo.

However, the seed-bearing structures are not like those of today’s ginkgo tree, Herendeen says. Ginkgo has large seeds with a fleshy outer covering, but U. mongoliensis has small, winged seeds.

As they developed, U. mongoliensis seeds were protected inside a tough, resinous, umbrella-like outer covering, which stayed almost completely closed, opening only to release the seeds.

The key to determining how U. mongoliensis is related to other seed plants lies in understanding its strange seed-bearing capsules.

While the U. mongoliensis seeds are dissimilar to those of any other living or extinct plant, preliminary comparisons connect them with the seed-bearing structures of two groups of extinct plants that may be part of the ginkgo lineage.

These comparisons and the unique features of U. mongoliensisindicate that ginkgo is the last living member of a group of plants that was much more diverse and important in the past.

Ginkgo biloba, primarily known today as a dietary supplement to enhance memory, also plays an important role in the understanding of seed plant evolution,” says Simon Malcomber, program director in NSF’s Division of Environmental Biology. “This research expands our understanding of the diversity in this enigmatic group, in addition to helping clarify relationships among seed plants more generally.”

In addition, the researchers collected other fossils from the Tevshiin Govi mine, including seed plants related to modern pines, spruces, swamp cypresses and redwoods.

Also present in the ancient swamp forests of central Mongolia were a variety of extinct plants thought to be early conifers, but that have no clear living relatives.

“Knowing the diversity of plants in Cretaceous environments provides a better understanding of potential food sources for animals such as plant-eating dinosaurs,” says Judy Skog, program director for paleontology in NSF’s Division of Earth Sciences. “Once the diversity of plants decreases, as this paper indicates is true for the relatives of ginkgo, animal life also declines.”

Scientists have long known about dinosaurs from the Cretaceous of Mongolia, but only now are the plants that supported those extinct animals coming into sharper focus.

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

Citation courtesy: National Science Foundation. “Paleontologists find fossil relative of Ginkgo biloba: Reconstruction of the ancient, dinosaur-era relative of today’s Ginkgo biloba plant.” ScienceDaily. ScienceDaily, 8 March 2017. <www.sciencedaily.com/releases/2017/03/170308114803.htm>.

Sparalepis tingi gen : A fish may have evolved prior to the ‘Age of Fish’

Key: WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev

An ancient fish species with unusual scales and teeth from the Kuanti Formation in southern China may have evolved prior to the “Age of Fish,” according to a study published March 8, 2017 in the open-access journal PLOS ONE by Brian Choo from Flinders University, Australia, and colleagues at the Institute of Vertebrate Paleontology and Paleoanthropology, China.

This is a holotype and interpretative reconstruction of Sparalepis tingi gen. et sp. nov. Credit: Brian Choo: CCAL

This is a holotype and interpretative reconstruction of Sparalepis tingi gen. et sp. nov.
Credit: Brian Choo: CCAL

The Devonian Period (419.2 — 358.9 million years ago) is popularly called the “Age of Fishes” because of the apparent increase in the abundance and variety of jawed fishes when compared with the preceding Silurian Period (443.7 — 419.2 million years ago). Until recently, the Silurian fossil record of jawed vertebrates has been based on highly fragmentary remains, limiting our understanding of their early evolution. Recent discoveries from the Kuanti Formation of Yunnan, southwestern China, have dramatically enhanced our knowledge, with several superbly preserved fish species described in recent years. The fish-bearing sediments of the Kuanti Formation have been dated to the latter part of the Silurian, about 423 million years ago.

Sparalepis tingi gen. et sp. nov., holotype V17915. Detailed images of median dorsal plates and appendicular skeleton. A. 1st (left) and 2nd (right) median dorsal plates in dorsal view. B. interclavicle and right dermal pelvic girdle. C. left cleithrum in flattened ventrolateral view. Abbreviations: dpg, dermal pelvic girdle; icl, interclavicle; sp, pectoral fin spine.

Sparalepis tingi gen. et sp. nov., holotype V17915. Detailed images of median dorsal plates and appendicular skeleton.
A. 1st (left) and 2nd (right) median dorsal plates in dorsal view. B. interclavicle and right dermal pelvic girdle. C. left cleithrum in flattened ventrolateral view. Abbreviations: dpg, dermal pelvic girdle; icl, interclavicle; sp, pectoral fin spine.

Now, Choo and colleagues have described a new genus and species of Kuanti fish, Sparalepis tingi, which represents only the second Silurian bony fish based on more than isolated fragments. This new form, along with its contemporary Guiyu and the slightly more recent Psarolepis, possesses spine-bearing pectoral and pelvic girdles, features once thought to be restricted to the armored placoderm fishes. Sparalepis and its kin may represent an early radiation of stem-sarcopterygians, ancient cousins of modern lungfish, coelacanths and tetrapods.

Scales of Sparalepis tingi gen. et sp. nov., holotype V17915. A. generalised reconstructed silhouette of Sparalepis showing scale zones based on the scheme of Esin [30]. B. Area A scales from the right flank. C. Area A scales from the left flank. D. Area B scale in anterolateral view. E. Area E scales. Abbreviations: l.a, anterior ledge; n.a, anterior notch.

Scales of Sparalepis tingi gen. et sp. nov., holotype V17915.
A. generalised reconstructed silhouette of Sparalepis showing scale zones based on the scheme of Esin [30]. B. Area A scales from the right flank. C. Area A scales from the left flank. D. Area B scale in anterolateral view. E. Area E scales. Abbreviations: l.a, anterior ledge; n.a, anterior notch.

But Sparalepis also has an unusual scale morphology which distinguishes it from its cousins. The scales are particularly tall, thick and narrow, with the ones at the front having interlocking mechanisms on both the outer and inner surfaces. The closely packed squamation resembles a wall of shields, giving rise to the genus name of Sparalepis, a mixture of ancient Persian and Greek meaning “shield scale.”

Life restoration of Sparalepis tingi (foreground) and other fauna from the Kuanti Formation. Also in the scene are numerous conodont animals, a pair of the maxillate placoderm Entelognathus (middle distance) and two examples of the osteichthyan Megamastax (background), the largest known Silurian vertebrate. Illustration by Brian Choo, released under Creative Commons Attribution Licence CC BY 4.0, 2016. http://dx.doi.org/10.1371/journal.pone.0170929.g009

Life restoration of Sparalepis tingi (foreground) and other fauna from the Kuanti Formation.
Also in the scene are numerous conodont animals, a pair of the maxillate placoderm Entelognathus (middle distance) and two examples of the osteichthyan Megamastax (background), the largest known Silurian vertebrate. Illustration by Brian Choo, released under Creative Commons Attribution Licence CC BY 4.0, 2016.
http://dx.doi.org/10.1371/journal.pone.0170929.g009

Sparalepis adds to an ever-growing list of bizarre ancient fishes from the Silurian and earliest Devonian of Yunnan, suggesting that this region may have been an early center of diversification for the jawed vertebrates. The “Age of Fishes” appears to have arrived early during the Silurian of southern China.

Citation:Brian Choo, Min Zhu, Qingming Qu, Xiaobo Yu, Liantao Jia, Wenjin Zhao. A new osteichthyan from the late Silurian of Yunnan, China. PLOS ONE, 2017; 12 (3): e0170929 DOI: 10.1371/journal.pone.0170929

Key: WFS,World Fossil Society,Riffin T Sajeev,Russel T Sajeev