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From dig to digital: Australia’s iconic dinosaurs as you’ve never seen them before

QUT is bringing five iconic Australian dinosaurs to full-sized life, including ‘Banjo’ the Australovenator and the giant herbivore Muttaburrasaurus, on The Cube, the world’s largest interactive learning display.

It’s Australia’s largest known meat-eating dinosaur but until now we’ve never seen how Australovenator moved – not even the man who dug it up and named it.

QUT is bringing five iconic Australian dinosaurs to full-sized life, including ‘Banjo’ the Australovenator and the giant herbivore Muttaburrasaurus, on The Cube, the world’s largest interactive learning display.

The team of Cube Studio game developers has partnered with the Queensland Museum’s renowned palaeontologist Dr Scott Hocknull to recreate the hyper-realistic, scientifically accurate prehistoric reptiles in a virtual environment.

Cube Studio manager Sean Druitt said all Dino Zoo animals were backed by the latest research and evidence on their textures, colouring, sounds, behaviours and movement. Even the environment and food sources in the zoo are scientifically accurate.

The Cube allows everyone to get as close to Jurassic Park as possible – without the danger of being eaten.

“It’s the first time ever these five Australian dinosaurs have been animated in 3D and given a realistic and scientifically defendable treatment.

“The Cube is a huge canvas, providing the perfect opportunity to recreate these dinosaurs in true scale and to give the public a real-world experience of these creatures.

Mr Druitt said, where there was scant information from fossil records, like skin colouring, his team had drawn inspiration from Dr Hocknull’s scientifically studied real-world analogues from creatures living today.

“The dinosaurs’ rich colour and texture might surprise you because it’s nothing like bland browns and greys from picture books – we’re re-educating the public about what they think they know about dinosaurs,’ Mr Druitt said.

“In the case of Banjo, which hunted in the Australian outback of the Late Cretaceous, the best match for living carnivores operating in a similar environment is a cross between a Cassowary, a Komodo Dragon and the African Wild Dog. Banjo’s markings are based on a combination of these three living species.”

Australovenator, is the most complete meat-eating dinosaur ever found in Australia, and is Australia’s answer to the Velociraptor – only three times the size, with 70 razor-sharp teeth and three enormous claws on each hand.

Dr Hocknull led the discovery of its 95 million-year-old bones near Winton in Queensland in 2006.

He also scientifically described and named the dinosaur Australovenator wintonensis (which means “Southern Hunter from Winton”) in 2009.

“Seeing Australovenator walking around for the first time was literally a childhood dream come true for me,” said Dr Hocknull.

“It’s been an incredible experience to discover, name, visualise it in 3D, and then control its movements via remote control within its digital universe.

“I’ve thoroughly enjoyed working with Sean and his team – it’s not every day you get to work with a crack team of developers on something you’ve wanted to do for years.

“This is a unique project because never before have game developers and a palaeontologist worked so closely side by side throughout the whole process to ensure the animals are as realistic as our knowledge allows.

“I’ve been providing information and feedback every step of the way, a luxury moviemakers and documentarians just don’t have the budgets for.

Dr Hocknull said he had learned as much about animation as he had taught the game developers about real-world dinosaurs.

“Seeing these animals fleshed out has very much informed my own research.

“Having that dino’s-eye view of its movement and its environment has given me insights I wouldn’t normally get just looking at the bones – it’s allowed me to form some new hypotheses about their biomechanical movements and behaviour of these dinosaurs that I’m now able to investigate as part of my ongoing research.”

Mr Druitt said the process of creating Dino Zoo had also been eye-opening for his team, who have had to rewrite the rules of animation in order to remain realistic.

“For example, a common trick we use in game development and animation is to over-exaggerate movement and actions to create drama and effect – like exaggerating the inward and outward movement of a rib cage to show that an animal is breathing,” he said.

“But in the real world we don’t see an elephant’s rib cage moving when it breathes normally, and neither would you see a dinosaur’s ribs moving with its breathing.

“We’ve had to strip back a lot of our creative liberties in order to remain true to accuracy.”

Dino Zoo was built using the Unity game engine.

When the free installation at The Cube opens to the public in December, it will house 10 dinosaur species, separated into front and back paddocks by a virtual fence.

Each dinosaur will be equipped with artificial intelligence, allowing it to roam the paddocks at will, based on a set of pre-programmed behavioural parameters.

“You’ll see the dinosaurs doing something different every time you visit, rather than performing the same series of choreographed actions over and over,” Mr Druitt said.

“You can watch them and be awed by them just as you would a lion at a physical zoo, and it will be up to the dinosaurs what they want to do and when.

Dino Zoo will include additional digital activities including a dig pit simulator and an interactive Earth timeline. It will be backed by a series of STEM workshops for visiting high school students.

The public will get a sneak peak of Queensland’s very own Australovenator and Muttaburrasaurus on the run when Dr Hocknull presents a TEDx talk at QUT on September 5. Visit the TEDxQUT website for details.

Note: The above post is reprinted from materials provided by Queensland University of Technology.

Are we wiser about tsunamis? Expert says yes and no

This image shows Northwestern University tsunami expert Emile Okal surveys the devastation of the Pacific island Niuatoputapu, Tonga, following the 2009 Samoa tsunami. The site was a palm grove where all the trees, towering more than 50 feet high, were felled by the wave. In a recent study, Okal found mixed results as to how much wiser people have become about these natural events. Credit: Emile A. Okal, Northwestern University

The world may not be well prepared for the next significant tsunami, reports Northwestern University tsunami expert Emile A. Okal in a new study that includes a “wisdom index” for 17 tsunamis since 2004.

The 2004 Sumatra-Andaman tsunami was the most devastating in recorded history, killing more than 225,000 people, including thousands of tourists. In his review of that event and 16 other significant tsunamis since then, Okal used the concept of a “wisdom index” to grade the performance of scientists, decision-makers and populations at risk. The index was based on the warning issued (or not) during the event and on the response of the population.

Okal found mixed results as to how much wiser people have become about these natural events and how to reduce their impact.

“We cannot foresee how well we will be doing in the next tsunami,” said Okal, a seismologist and professor of Earth and planetary sciences in the Weinberg College of Arts and Sciences. “I found that mitigation of these 17 tsunamis was rather erratic — there is not sustained improvement with time, nor a clear correlation of the wisdom index with the geographic location of the tsunami source.”

In his paper, Okal reflects on the progress made since the catastrophic event of 2004 in various aspects of tsunami science, warning and mitigation and more generally in tsunami resilience, i.e., the preventive adaptation of communities to this form of natural hazard.

“The Quest for Wisdom: Lessons From Seventeen Tsunamis, 2004-2014” was published Sept. 21 by the journal Philosophical Transactions of the Royal Society A.

In addition to the mixed “wisdom indices,” the key results of Okal’s study are:

  • Education is important. “One thing is clear, saving human lives is easier when individuals are educated to the risks in question,” he said. “Education, in all its forms — formal, classroom, drills, ancestral — works.”
  • Substantial progress has been made in terms of controlling tsunami hazard in the “far field” (a tsunami that originates from a source greater than 1,000 kilometers, or 620 miles, away). Only a handful of deaths have occurred in far field tsunamis since the 2004 Sumatra tsunami.
  • The major challenge remains the so-called “tsunami earthquakes,” events which are not strong enough to alarm the population at risk, yet have considerable tsunami potential.
  • Some paradigms which led scientists to think that mega-earthquakes occur only in certain geological environments — featuring young and fast tectonic plates — had to be revised or abandoned. “For lack of a better understanding, scientists must now assume that mega-earthquakes may occur at any subduction zone,” Okal said. (A subduction zone is where one tectonic plate sinks below another.)

Okal stresses the importance of incorporating any new knowledge into tsunami warning procedures and public awareness.

“In this day and age of professional and leisure travel, the general public worldwide should be aware of tsunami risk,” Okal said. “The 2004 Sumatra event was the most lethal disaster in the history of Sweden. The country lost about 500 tourists on the beaches of Thailand.”

Okal said his research was strongly influenced by his 20-year collaboration with Costas Synolakis, director of the Tsunami Research Center at the University of Southern California.

In a separate article in the same issue of the journal, Synolakis critically assesses the 2011 Fukushima Nuclear Power Plant accident in Japan and concludes it was due to the cumulation of a number of scientific, engineering and management blunders that could and should have been prevented.

Reference:
Emile A. Okal. The quest for wisdom: lessons from 17 tsunamis, 2004–2014. Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2015; 373 (2053): 20140370 DOI: 10.1098/rsta.2014.0370

Note: The above post is reprinted from materials provided by Northwestern University. The original item was written by Megan Fellman.

New Geosphere themed issue: The anatomy of rifting

This is a NASA image created by Jesse Allen, Earth Observatory, using data provided courtesy of the MODIS Rapid Response team. Credit: NASA

Research at continental rifts, mid-ocean ridges, and transforms has shown that new plates are created by extensional tectonics, magma intrusion, and volcanism. Studies of a wide variety of extensional processes, ranging from plate thinning to magma intrusion, have helped scientists understand how continents are broken apart to form ocean basins. However, deformation processes vary significantly during the development of continental rifts and mid-ocean ridges. In addition, ocean ridges are offset along their length by major transform faults, the initiation of which is poorly understood.

Data documenting active processes have proven difficult to obtain because most ridges are submerged with only rare portions of the divergent plate boundary being exposed on land. Therefore current knowledge about the length and time scales of magmatism and faulting during rift evolution as well as the mechanisms of initial development of mid-ocean ridges and transforms is limited. In this themed issue, Carolina Pagli and colleagues present contributions that document the wide variety of processes acting at divergent plate boundaries and transforms in order to synthesize some of the most relevant research topics about plate extension and to identify the important questions that remain unanswered.

Reference:
Introduction: Anatomy of rifting: Tectonics and magmatism in continental rifts, oceanic spreading centers, and transforms Carolina Pagli et al., Dipartimento di Scienze della Terra, Università di Pisa, Via S. Maria 53, 56126 Pisa, Italy. New themed issue: Anatomy of Rifting: Tectonics and Magmatism in Continental Rifts, Oceanic Spreading Centers, and Transforms. This article is OPEN ACCESS online at DOI: 10.1130/GES01082.1

Note: The above post is reprinted from materials provided by Geological Society of America.

The Karoo Basin and the end Permian mass extinction

This photo-like image of South Africa was captured on April 12, 2010, by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite. Credit: NASA

Earth’s biosphere witnessed its greatest ecological catastrophe in the latest Permian, dated to about 251.9 million years ago. The current model for biodiversity collapse states that both marine and terrestrial animals were impacted simultaneously, as a consequence of global climate change.

On land, South African vertebrate fossils, and the stratigraphic record in which they are preserved, are reported to document the extinction and recovery associated with the crisis. The pattern — reported as the end of the Dicynodon biozone and beginning of the Lystrosaurus biozones — has been extrapolated to other continents and hemispheres and used to recognize the boundary event globally.

Yet, to date, there has been no age constraint placed near the turnover in vertebrate fossils in this, or any, area. In this new study for Geology, Robert Gastaldo and colleagues present new multidisciplinary data from the Karoo Basin and call into question our current understanding of the terrestrial response to the End Permian Mass Extinction. Paleoecological evidence does not support the reported coincidence of climate aridification, floral collapse, and tetrapod turnover. Similarly, magnetostratigraphic and geochronometric data, when conservatively interpreted, indicate that the turnover between the biozones occurred in the early Changhsingian, more than 1.6 million years beforehand, and was not coeval with the marine mass extinction event.

Reference:
Is the vertebrate-defined Permian-Triassic boundary in the Karoo Basin, South Africa, the terrestrial expression of the end-Permian marine event?
Robert A. Gastaldo et al., Dept. of Geology, Colby College, Waterville, Maine 04901, USA This article is OPEN-ACCESS online; DOI: 10.1130/G37040.1

Note: The above post is reprinted from materials provided by Geological Society of America.

Researchers discover new lineage of prehistoric, plankton-eating sharks

DePaul University paleobiologist Kenshu Shimada’s rendering of a Pseudomegachasma shark hypothesizes it had a large mouth with many small teeth. Credit: Image courtesy of Kenshu Shimada 

An international team of scientists has discovered a new lineage of extinct plankton-feeding sharks, Pseudomegachasma, that lived in warm oceans during the age of the dinosaurs nearly 100 million years ago. The fossil sharks had tiny teeth very similar to a modern-day, plankton-eating megamouth shark.

The study, “A new clade of putative plankton-feeding sharks from the Upper Cretaceous of Russia and the United States,” is published in the September issue of the Journal of Vertebrate Paleontology.

Lead author, Kenshu Shimada, professor of paleobiology at DePaul University, said the findings are based on newly collected tiny fossil teeth, as well as a reinterpretation of previously reported specimens from Cretaceous rocks in the U.S. and Russia.

“The study is significant because Pseudomegachasma would represent the oldest known plankton-feeding shark in the fossil record,” said Shimada. He added that these sharks would have evolved independent of the four known lineages of modern-day planktivorous cartilaginous fishes: the megamouth sharks, basking sharks, whale sharks, and manta rays.

Pseudomegachasma means “false megamouth shark” due to its dental features superficially nearly identical to the modern-day plankton-eating megamouth shark or Megachasma that evolved much later in time. The new genus is represented by two extinct species, Pseudomegachasma casei from Russia and Pseudomegachasma comanchensis from the U.S. that evolved from a group of extinct sandtiger sharks that likely had a fish-eating diet.

Reference:
Kenshu Shimada, Evgeny V. Popov, Mikael Siversson, Bruce J. Welton, Douglas J. Long. A new clade of putative plankton-feeding sharks from the Upper Cretaceous of Russia and the United States. Journal of Vertebrate Paleontology, 2015; 35 (5): e981335 DOI: 10.1080/02724634.2015.981335

Note: The above post is reprinted from materials provided by DePaul University.

Africa’s earliest coelacanth have been found in a 360 million year-old fossil

Serenichthys coelacanth holotype is shown. Credit: Wits University

Various specimens of Africa’s earliest coelacanth have been found in a 360 million year-old fossil estuary near Grahamstown, in South Africa’s Eastern Cape.

More than 30 complete specimens of the new fossil species, Serenichthys kowiensis, were collected from the famous Late Devonian aged Waterloo Farm locality, by palaeontologist Dr Robert Gess and described by him in collaboration with Professor Michael Coates of the University of Chicago.

Gess did the research whilst he was completing his PhD at the Evolutionary Studies Institute at the University of the Witwatersrand. An article describing the new species will be published in the in the Zoological Journal of the Linnean Society of London in August.

“Remarkably, all of the delicate whole fish impressions represent juveniles. This suggests that Serenichthys was using a shallow, waterweed-filled embayment of the estuary as a nursery, as many fish do today,” says Gess.

The fossils come from black shales originally disturbed by road works at Waterloo Farm. These shales are the petrified compacted remains of mud, which was deposited in the quiet reaches of an estuary not unlike some of those along the Eastern Cape coast today.

“This earliest known record of a coelacanth nursery foreshadows a much younger counterpart, known from the 300 million year old Mazon Creek beds of Illinois in the United States,” says Gess.

“This glimpse into the early life history of ancient coelacanths raises further questions about the life history of the modern coelacanth, Latimeria, which is known to bear live young, but whether they, too, are clustered in nurseries remains unknown,” explains Coates.

360 million years ago, Africa was part of the southern supercontinent Gondwana, made up of Africa, India, Australia, Antarctica and South America. At that time, the rocks of Waterloo Farm were forming along the shores of the semi-enclosed Agulhas Sea, not far from the South Pole.

Gess originally identified coelacanth remains from the locality whilst carrying out excavations at Waterloo Farm in the mid-1990s under the supervision of Dr Norton Hiller, of the Rhodes University Geology Department. These fossils were not, however, well enough preserved to be reconstructed and described. His painstaking excavation of tons of shale salvaged during subsequent roadworks has now shed light on dozens more specimens, a few of which are preserved in exquisite detail.

These were prepared under a microscope and have allowed the species to be reconstructed in minute detail. They prove to be a new genus and species.

Coelacanths are believed to have arisen during the Devonian Period (about 419.2 ± 3.2 million years ago), however only five species of reconstructable Devonian coelacanths have previously been described, in addition to a number of very fragmentary remains. None of these came from Africa, but rather from North America, Europe, China and Australia. The new species gives important additional information on the early evolution of coelacanths.

“According to our evolutionary analysis (conducted by Gess and Coates), it is the Devonian species that most closely resembles the line leading to modern coelacanths,” says Gess.

The new species was discovered a mere 100km from the mouth of the Chalumna River, off which the type specimen of Latimeria chalumnae (the first discovered modern coelacanth) was caught in 1938.

Furthermore, the Geology Department at Rhodes, where Gess was based when he found his first fossil coelacanth, is on the site of the former Chemistry Department where Latimeria was first described. In keeping with the naming of its living relative (after an Eastern Cape river), the species name of the new fossil form, kowiensis, is after the Kowie River which rises among the hills where it was found, and the genus name, Serenichthys, honours Serena Gess, who provided land for the storage of more than 70 tons of black shale rescued from roadworks for ongoing research — in which all the new material was found.

All specimens have been deposited in the palaeontological collection of the Albany Natural History Museum, in Grahamstown, Eastern Cape Province, South Africa.

Note: The above post is reprinted from materials provided by University of the Witwatersrand.

Chinese continental shelf of exotic origin collided with continental China 100 million years ago

Portion of the world topographic map, highlighting the continental China and its adjacent land and seas (Google Map, 2015) to illustrate: (1) the Chinese continental shelf (basement of the East and South China Seas) to be of exotic origin; (2) arrival of the buoyant and unsubductable oceanic plateau or micro-continent at the trench jammed the trench at ~ 100 Ma; (3) the jammed trench location is shown in red dashed curve along the southeast coast of continental China although it is unclear in the north as indicated by the dashed light blue curve with question marks; (4) The yellow “drop” dots are granitoid sample locations with ages in the literature. The thick dashed purple line labeled E-W GGL approximates the East-West Great Gradient Line topographically separating the plateau to the west from the low-land hilly plain to the east. Credit: ©Science China Press

It has been axiomatically accepted that the basement of a continental shelf is the offshore extension and geologically part of the same continental lithosphere. While this notion may hold true in places, our analysis of the distribution of Jurassic-Cretaceous granitoids throughout the entire eastern continental China in space and time led us to the conclusion that the basement of the Chinese continental shelf (beneath East China Sea and South China Sea) is of exotic origin geologically unrelated to the continental lithosphere of eastern China. This exotic terrane of a sizeable mass with large compositional buoyancy could be either an oceanic plateau or a micro continent, which was transported by, or along with, the paleo-Pacific plate moving in the course of NW direction and subducting beneath the eastern margin of the continental China in the Mesozoic, responsible for the granitoids with emplacement ages of ~ 190 Ma to ~ 88 Ma.

The termination of the granitoid magmatism throughout the vast region at ~ 88 Ma manifests the likelihood of subduction cessation at this time or more likely shortly beforehand, probably at ~ 100 Ma. Subduction stops only if the trench is jammed by a sizable terrane that is compositionally buoyant and physically unsubductable. The basement of the Chinese continental shelf is understood to be such an unsubductable mass of either an oceanic plateau or micro continent as said above that collided with the eastern margin of the continental China and jammed the trench at ~ 100 Ma.

The trench jam at ~ 100 Ma led to the Pacific plate to change its course of motion from NW to NNW and to subduct beneath the predecessors of the Kamchatka and western Aleutian trenches as manifested by the age progressive Emperor Seamount Chain of the Hawaiian hotspot origin. This Pacific plate re-orientation produced a transform boundary between the NNW moving Pacific plate and the newly accreted eastern Asian continental plate, which explains the ~ 40 Myrs’ time gap of subduction related magmatism in the greater western Pacific region before the present-day western Pacific subduction began at ~ 50 Ma. Because of the large compositional contrast across this transform boundary, it may have evolved into a trench with oblique subduction until ~ 43 Ma when the Pacific plate changed its course again back to the NW direction as manifested by the ~ 43 Ma kink and age progressive Hawaiian Seamount Chain of the Hawaiian hotspot origin.

The locus (or “suture”) of the jammed trench at 100 Ma is predicted to locate on the Chinese continental shelf in the vicinity of, and parallel to, the Southeast coastal line (red dashed curve in Fig. 1). The curved arc-shape of the coastal line is inherited from the pre-100 Ma arc-shaped trench, which is similar in both curvature and size to the India-Asia collision arc (red solid curve in Fig. 1). To locate the locus in the northern section in the East China Sea and Yellow Sea is not straightforward because of the recent (< 20 Ma) tectonic re-organization associated with the opening of the Sea of Japan (see the light blue dashed line with question marks in Fig. 1).

The eastern continental China in the Mesozoic can be interpreted as an active continental margin, but NOT an Andean-Type margin as treated by many. This is because the granitoids do not define “magmatic arcs” at any given time, but distribute randomly in space and time in a wide zone in excess of > 1000 km. This observation indicates the likelihood of the presence of a stagnant paleo-Pacific slab in the mantle transition-zone beneath the region as is the case in the Cenozoic, which is seismically observed at present. The stagnant slab under heating by the ambience above and below caused the slab dehydration. This dehydration caused a sequence of processes of geodynamic and geological significance. The released water facilitated the formation of hydrous melt within and above the transition zone, which percolated through and metasomatized the upper mantle, weakened the base of the lithosphere and transformed it into asthenosphere, hence having thinned lithosphere in the Mesozoic, accompanied by melting of the being-converted “lithospheric material” to produce basaltic melt as the heat source for crustal melting and the granitoid magmatism. Such within plate magmatism was ultimately triggered by subduction and subducted slabs, and can be readily understood as a special (vs. plate boundary zone) consequence of plate tectonics.

This new understanding on the origin of the Chinese continental shelf introduces an innovative hypothesis for consideration and testing. Basement penetration drilling on ideal sites of the shelf in collaboration with industries and IODP is expected to offer the most effective testing towards a genuine understanding of the tectonic evolution of the greater western Pacific since the Mesozoic in a global tectonic context.

Reference:
Niu YL, Liu Y, Xue QQ, Shao FL, Chen S, Duan M, Guo PY, Gong HM, Hu Y, Hu ZX, Kong JJ, Li JY, Liu JJ, Sun P, Sun WL, Ye L, Xiao YY, Zhang Y (2015) Exotic origin of the Chinese continental shelf: New insights into the tectonic evolution of the western Pacific and eastern China since the Mesozoic. Science Bulletin link.springer.com/article/10.1007%2Fs11434-015-0891-z

Note: The above post is reprinted from materials provided by Science China Press.

Unexceptional flooding can cause significant erosion, study shows

The Ricobayo Dam in North West Spain. Credit: Iberdrola 

Exceptionally large floods are not necessary to trigger the creation of gorges within hard rocks such as granite, according to a new study involving Plymouth University.

Researchers from Spain and the UK used a combination of archive images and survey data to demonstrate how the diversion of water down an overspill channel from a dam in North West Spain had a profound impact on its surroundings.

It showed there was rapid erosion in the six years following the dam’s construction, with just five flood events creating a new gorge more than 270m long, 160m wide and 100m deep.

While such change might be expected in cases of extremely large flood events (for example glacial lake outburst floods), this case study suggests it can also be caused by small to moderate events, with the structural pattern of the bedrock being the primary control on landscape change.

Scientists believe this study, published in Nature Communications, could advance our understanding about the potential for gorge erosion across the world, but also where similar morphological features have been identified on other planetary bodies such as Mars.

One of the paper’s authors Dr Anne Mather, Associate Professor in Physical Geography at Plymouth University, said:

“If you showed someone images of the gorge, they would probably say the erosion had taken place over a long period with exceptional flooding. To put it into context, the heads of Niagara Falls and Victoria Falls retreat at around 1.2-2m and 0.5m per year (respectively), but here we saw more than 270m over the space of just six years. It demonstrates that the rate of water flow is not always the major contributing factor to gorge erosion.”

Dr Mather and Dr Martin Stokes, from the University’s School of Geography Earth and Environmental Sciences, worked on the study with colleagues from the Universidad Nacional de Educación a Distancia (UNED) and the Universidad Complutense de Madrid.

They analysed archives relating to the Ricobayo dam, which was constructed along the Río Esla in North West Iberia in the 1930s, in an area previously characterised by seasonal floods.

When it was built, the dam included an unlined spillway and – after its completion in 1933 – a series of overtopping floods occurred. Additional flood gates were added in 1938 and only one incidence of further overtopping being recorded in early 1939.

As such, the widening and retreating effects on the gorge can be confined to this period, with the data and images providing an almost unrivalled snapshot of bedrock erosion.

Dr Mather added:

“There are countless instances where erosion is said to have happened over time, but the level of information relating to the Ricobayo means we can paint a very detailed picture of what happened here. As such, this study highlights several key observations concerning the morphological adjustment of bedrock rivers on Earth and Mars. It is a particularly good analogue for what can happen during a naturally occurring river diversion, or any sudden change to a river that creates a nick point in the system, providing us with an insight into how a bedrock river may respond to environmental change.”

Reference:
“Exceptional river gorge formation from unexceptional floods.” Nature Communications 6, Article number: 7963 DOI: 10.1038/ncomms8963

Note: The above post is reprinted from materials provided by University of Plymouth.

New dinosaur species unveiled by Woodland Park paleontology team

Three-year-old Brynley Lorentz of Colorado Springs checks out a new dinosaur Wednesday, September 16, 2015, at the Rocky Mountain Dinosaur Resource Center in Woodland Park. The dinosaur is believed to be a new, never-before-seen species of prehistoric herbivore and was discovered during excavations at the fossil-rich Judith River Formation in Montana. The creature is nicknamed “Ava” due to initial similarities to Avaceratops. Photo Credit: Mark Reis, The Gazette

The Rocky Mountain Dinosaur Resource Center in Woodland Park on Wednesday unveiled what is believed to be a new, never-before-seen species of prehistoric herbivore discovered by its field team during excavations at the fossil-rich Judith River Formation in Montana.

Nicknamed “Ava” due to initial similarities to Avaceratops, the long-tailed plant eater grazed the Western Interior during the Late Cretaceous Period about 75 million years ago.

The creature had a Triceratops-shaped head and compact body that was “maybe the equivalent of a two-or-three-year-old rhino calf … (but) we don’t have a whole lot of barrel-chested animals around today where 30 percent of the critter is tail,” said Anthony Maltese, the center’s curator and a member of the field excavation team for Triebold Paleontology, Inc. The firm, whose main lab is housed at the center, began uncovering the skeleton from private ranch land in 2012.

The new ceratopsian dinosaur has not been assigned a scientific name differentiating it from the species it closely resembles; that will come after official confirmation by outside experts, Maltese said. In the meantime, the center’s in-house experts are confident their “Ava” is a “Not-Ava.”

“Some differences were major, and some were minor,” Maltese said. “There were enough differences we were sure we’d found something completely new.”

Using mostly hand-held brushes and tools, the team from Triebold Paleontology spent four months uncovering and removing the skull and about 200 disarticulated bones from solid sandstone. The bones were transported to the center’s high-tech lab, where they were restored, molded and cast and used to create a model that could be reconstructed and mounted for display. Digital mirror-imaging and 3D printing were used to recreate the missing pieces of a find that was remarkably intact.

“It’s nice to have a new species, but to have a body so well represented …,” said Mike Triebold, a professional fossil hunter whose $3.5 million dinosaur center houses a public museum as well as one of the world’s more active paleo labs. “The amazing thing about this specimen (is) many, many, many times scientists will create a specimen out of a few bones, but we found 85 percent of the animal.”

Since founding the company in 1989, Triebold and his teams have found about a half-dozen skeletons that were confirmed to represent new species of prehistoric land and marine animals, and those discoveries can be seen, as fully articulated skeletal models, in the museum. Triebold’s firm was among the first to offer molding and casting of dinosaur skeletons, and its creations are on display in universities and museums worldwide.

The original fossilized “Ava” bones will be acquired by a museum or other institution, Triebold said, and the inaugural model cast from those bones will join the center’s traveling Darwin and the Dinosaurs exhibit. First, though, Triebold booked it for a celebrity appearance at next month’s annual meeting of the Society of Vertebrate Paleontology in Dallas.

“All the ceratopsian nerds will be all over it, arguing and comparing and praising. That’s what they do,” Triebold said.

Note: The above post is reprinted from materials provided by Colorado Springs Gazette.

‘Tree of life’ for 2.3 million species released

This circular family tree of Earth’s lifeforms is considered a first draft of the 3.5-billion-year history of how life evolved and diverged. Credit: opentreeoflife.org

A first draft of the “tree of life” for the roughly 2.3 million named species of animals, plants, fungi and microbes — from platypuses to puffballs — has been released.

A collaborative effort among eleven institutions, the tree depicts the relationships among living things as they diverged from one another over time, tracing back to the beginning of life on Earth more than 3.5 billion years ago.

Tens of thousands of smaller trees have been published over the years for select branches of the tree of life — some containing upwards of 100,000 species — but this is the first time those results have been combined into a single tree that encompasses all of life. The end result is a digital resource that available free online for anyone to use or edit, much like a “Wikipedia” for evolutionary trees.

“This is the first real attempt to connect the dots and put it all together,” said principal investigator Karen Cranston of Duke University. “Think of it as Version 1.0.”

The current version of the tree — along with the underlying data and source code — is available to browse and download at https://tree.opentreeoflife.org.

It is also described in an article appearing Sept. 18 in the Proceedings of the National Academy of Sciences.

Evolutionary trees, branching diagrams that often look like a cross between a candelabra and a subway map, aren’t just for figuring out whether aardvarks are more closely related to moles or manatees, or pinpointing a slime mold’s closest cousins. Understanding how the millions of species on Earth are related to one another helps scientists discover new drugs, increase crop and livestock yields, and trace the origins and spread of infectious diseases such as HIV, Ebola and influenza.

Rather than build the tree of life from scratch, the researchers pieced it together by compiling thousands of smaller chunks that had already been published online and merging them together into a gigantic “supertree” that encompasses all named species.

The initial draft is based on nearly 500 smaller trees from previously published studies.

To map trees from different sources to the branches and twigs of a single supertree, one of the biggest challenges was simply accounting for the name changes, alternate names, common misspellings and abbreviations for each species. The eastern red bat, for example, is often listed under two scientific names, Lasiurus borealis and Nycteris borealis. Spiny anteaters once shared their scientific name with a group of moray eels.

“Although a massive undertaking in its own right, this draft tree of life represents only a first step,” the researchers wrote.

For one, only a tiny fraction of published trees are digitally available.

A survey of more than 7,500 phylogenetic studies published between 2000 and 2012 in more than 100 journals found that only one out of six studies had deposited their data in a digital, downloadable format that the researchers could use.

The vast majority of evolutionary trees are published as PDFs and other image files that are impossible to enter into a database or merge with other trees.

“There’s a pretty big gap between the sum of what scientists know about how living things are related, and what’s actually available digitally,” Cranston said.

As a result, the relationships depicted in some parts of the tree, such as the branches representing the pea and sunflower families, don’t always agree with expert opinion.

Other parts of the tree, particularly insects and microbes, remain elusive.

That’s because even the most popular online archive of raw genetic sequences — from which many evolutionary trees are built — contains DNA data for less than five percent of the tens of millions species estimated to exist on Earth.

“As important as showing what we do know about relationships, this first tree of life is also important in revealing what we don’t know,” said co-author Douglas Soltis of the University of Florida.

To help fill in the gaps, the team is also developing software that will enable researchers to log on and update and revise the tree as new data come in for the millions of species still being named or discovered.

“It’s by no means finished,” Cranston said. “It’s critically important to share data for already-published and newly-published work if we want to improve the tree.”

“Twenty five years ago people said this goal of huge trees was impossible,” Soltis said. “The Open Tree of Life is an important starting point that other investigators can now refine and improve for decades to come.”

This research was supported by a three-year, $5.76 million grant from the U.S. National Science Foundation (1208809).

Reference:
C. Hinchliff et al. Synthesis of Phylogeny and Taxonomy Into a Comprehensive Tree of Life. Proceedings of the National Academy of Sciences, 2015 DOI: 10.1073/pnas.1423041112

Note: The above post is reprinted from materials provided by Duke University.

“Living Fossil” Genome Decoded

The mysterious “living fossil,” Lingula anatina. Credit: OIST

A group of scientists from Okinawa Institute of Science and Technology Graduate University (OIST), Nagoya University, and the University of Tokyo decoded the first lingulid brachiopod genome, from Lingula anatina collected at Amami Island, Japan. The paper published in Nature Communications presents the results of their analysis of over 34,000 genes comprising the L. anatina genome and shows that despite Lingula’s reputation as a “living fossil” its genome is actively evolving.

The mysterious “living fossil”

Brachiopods are marine invertebrates with external shells and a stalk. They are often confused with molluscs; however, the resemblance is superficial. Unlike bivalves — clams and mussels — that have shells on the sides of their bodies, brachiopod shells are on the top and bottom. As a result, the plane of symmetry in a bivalve runs along the hinge; hence the two valves are mirror images of one another. In brachiopods the plane of symmetry is perpendicular to the hinge, so that the halves of the valves mirror each other.

Brachiopods are one of the first known examples of animal biomineralisation — a process whereby living organisms stiffen or harden tissues with minerals. The earliest discovered brachiopod fossils date to the early Cambrian period, approximately 520 million years ago. Brachiopods quickly spread all over the world and dominated the seas during the Paleozoic era (542-251 million years ago) and, by virtue of their mineralised shells, left an abundance of fossils.

Lingulid brachiopods had changed so little in appearance since the Silurian period (443-419 million years ago) that Darwin referred to them as “living fossils.” This term often misleads people into believing that these animals do not evolve anymore, but the present study shows otherwise.

Mollusc Cousins

The evolutionary origin of brachiopods and their relations to other species are still unclear. For years, scientists have been debating the phylogenetic position of brachiopods and molluscs, as well as their affinities for other animals in the same group, the Lophotrochozoa, comprising segmented worms, clams, oysters, snails, squids, and so on. The phylogenetic analysis of the Lingula genome indicates that brachiopods are close relatives to molluscs, and more distant cousins to segmented worms; however, their relations to other lophotrochozoans still require further investigation.

“At the molecular level, brachiopods are very similar to molluscs. Both are protostomes — their embryos form mouths first and anuses thereafter. However, brachiopod embryonic development is very different from that of molluscs: it resembles that of deuterostomes, in which embryos form anuses first and mouths second,” says Yi-Jyun Luo, the first author of the paper, “The results of the Lingula genome project will help future research of these differences and the roles that specific genes play in development of various brachiopod body structures.”

A “living fossil”? Not quite!

One would expect that “living fossils” would closely resemble their fossilised ancestors, not only in appearance but in genome as well. While that is close to true for coelacanths, other famous “living fossils,” which have the slowest molecular evolutionary rate among vertebrates, the Lingula genome has been evolving rapidly, despite the lack of changes in appearance.

Shells of fossilised and living Lingula show considerable diversity in chemical structure. Analysis of the soft tissues of fossils also suggests morphological changes among lingulid brachiopods. The authors of the paper also found significant changes in the genomic structure and gene families, contradicting the idea of a genuine “living fossil.” Interestingly, the Lingula genes associated with basic metabolism show the slowest evolutionary change among lophotrochozoans.

Parallel Evolution

One of the great mysteries of animal evolution is that vertebrates and Lingula, although evolutionarily distant, both use calcium phosphate and collagen fibres for biomineralisation. However, genomic scale comparisons show that Lingula lacks genes for bone formation and has different types of collagen fibres. This study indicates that Lingula and bony vertebrates have evolved independently and employ different mechanisms for hard tissue formation. It is an interesting example of parallel evolution.

The Lingula genome decoding sheds some light on the evolutionary history of brachiopods and lophotrochozoans as well as the origin of biomineralisation. Prof. Noriyuki Satoh, the head of the OIST Marine Genomics Unit and the last author of the paper, said, “This is one step toward untangling the mysteries of animal evolution. The study highlights the fact that various animals have taken evolutionary paths independently from one another.” He added, “Conserving the natural habitat for animal diversity is important. This research illustrates the well-nurtured tradition of zoological studies in Japan.”

Video

Reference:
Yi-Jyun Luo, Takeshi Takeuchi, Ryo Koyanagi, Lixy Yamada, Miyuki Kanda, Mariia Khalturina, Manabu Fujie, Shin-ichi Yamasaki, Kazuyoshi Endo, Noriyuki Satoh. The Lingula genome provides insights into brachiopod evolution and the origin of phosphate biomineralization. Nature Communications, 2015; 6: 8301 DOI: 10.1038/ncomms9301

Note: The above post is reprinted from materials provided by Okinawa Institute of Science and Technology Graduate University – OIST.

Pre-reptile may be earliest known to walk upright on all fours

About the same size as a cow, this pre-reptile also stood the same way — upright with its legs underneath. It may be the earliest known creature to do so, according to a new study. Credit: Morgan Turner

A newly published analysis of the bones of Bunostegos akokanensis, a 260-million-year-old pre-reptile, finds that it likely stood upright on all-fours, like a cow or a hippo, making it the earliest known creature to do so.To date all of the known pareiasaurs who roved the supercontinent of Pangea in the Permian era a quarter of a billion years ago were sprawlers whose limbs would jut out from the side of the body and then continue out or slant down from the elbow (like some modern lizards). Morgan Turner, lead author of the study in the Journal of Vertebrate Paleontology, expected Bunostegos would be a sprawler, too, but the bones of the animal’s forelimbs tell a different story.

“A lot of the animals that lived around the time had a similar upright or semi-upright hind limb posture, but what’s interesting and special about Bunostegos is the forelimb, in that it’s anatomy is sprawling-precluding and seemingly directed underneath its body–unlike anything else at the time,” said Turner who performed the analysis under the supervision of Professor Christian Sidor while a student at the University of Washington. Now Turner is a graduate student at Brown University. “The elements and features within the forelimb bones won’t allow a sprawling posture. That is unique.”

The findings allowed Turner, Sidor and her co-authors to characterize how Bunostegos might have looked. Standing like a cow, and about the same size.

“Imagine a cow-sized, plant-eating reptile with a knobby skull and bony armor down its back,” said co-author Linda Tsuji of the Royal Ontario Museum, who discovered the fossils in Niger along with Sidor and a team of paleontologists in 2003 and 2006.

Four forelimb findings

Turner examined much of the skeleton of several individuals. The findings that matter most, however, are all in the forelimbs. In particular, four observations make the case, she said, that Bunostegos stood differently than all the rest, with the legs entirely beneath the body.

Starting at the shoulder joint, or the glenoid fossa, the orientation of it is facing down such that the humerus (the bone running from shoulder to elbow) would be vertically oriented underneath. It would restrict the humerus from sticking out to the side, too.

Meanwhile Bunostegos’s humerus is not twisted like those of sprawlers. In a sprawler, the twist is what could allow the humerus to jut out to the side at the shoulder but then orient the forearm downward from the elbow. But the humerus of Bunostegos has no twist suggesting that only if the elbow and shoulders were aligned under the body, could the foot actually reach the ground, Turner said.

The elbow joint is also telling. Unlike in sprawling pareiasaurs, which had considerable mobility at the elbow, the movement of Bunostegos’s elbow is more limited. The way the radius and ulna (forearm bones) join with the humerus forms a hinge-like joint, and wouldn’t allow for the forearm to swing out to the sides. Instead, it would only swing in a back and forth direction, like a human knee does.

Finally, the ulna is longer than the humerus in Bunostegos, which is a common trait among non-sprawlers, Turner said.

“Many other sprawling 4-legged animals have the reverse ratio,” she said.

Going back 260 million years

The idea that Bunostegos would be an outlier in terms of its posture matches well with the idea that it was somewhat of an outlier in its choice of habitat.

“Bunostegos was an isolated pareiasaur,” Turner said.

Way back when, Niger was an arid place (like some of it is today) where plants and water sources might well have been few and far between. Scientists have associated walking upright on all fours with a more energy efficient posture than sprawling. For the long journeys between meals, Turner said, the upright posture might have been necessary for survival.

The significance of such an early example of the upright posture is that Bunostegos dates very far back on the evolutionary tree, pushing back the clock on when this posture shows up in evolution.

But Turner said she wouldn’t be surprised if other animals of the time are eventually also found to have similarities to this posture, which evolved independently in reptiles and mammals several times over the eras.

“Posture, from sprawling to upright, is not black or white, but instead is a gradient of forms,” Turner said. “There are many complexities about the evolution of posture and locomotion we are working to better understand every day. The anatomy of Bunostegos is unexpected, illuminating, and tells us we still have much to learn.” At Brown, Turner is working in the lab of Professor Stephen Gatesy, where she is studying a continuum of postures and locomotion in ancient creatures. In addition to Turner, Tsuji and Sidor, Oumarou Ide of the University of Niamey in Niger is an author of the study.

Reference:
Morgan L. Turner, Linda A. Tsuji, Oumarou Ide, Christian A. Sidor. The vertebrate fauna of the upper Permian of Niger—IX. The appendicular skeleton ofBunostegos akokanensis(Parareptilia: Pareiasauria). Journal of Vertebrate Paleontology, 2015; e994746 DOI: 10.1080/02724634.2014.994746

Note: The above post is reprinted from materials provided by Brown University.

Silica-sand deposits in Arizona

Figure 2. Distribution of the Bidahochi Formation in northeastern Arizona and adjacent New Mexico (modified from Dickinson, 2013). Also shown is a simplified outline of the extent of the Navajo Indian Reservation. In some areas mineral rights and surface rights are held by different parties.

Nearly pure quartz sands have become increasingly important for oil and gas production. Although used  for hydraulic fracturing (“fracking”) since at least the 1950s, the advent of directional drilling and improvements in hydraulic fracturing techniques have led to widespread exploitation of quartz sands that have appropriate properties for use in hydraulic fracturing(“fracsands”). Such sands are present in the upper Miocene to Pliocene upper Bidahochi Formation of northeastern Arizona. Other sand deposits are present in the State, but are not as well suited for use in hydraulic fracturing. This report is a brief review of the distribution and character of sands in Arizona that may have properties appropriate for use in hydraulic fracturing.

Bidahochi Formation

The Bidahochi Formation in northeastern Arizona(Figures1, 2)consists of three members: (1) a lower playa and lacustrine facies of middle Miocene age (Dallegge et al., 2001,2003), (2) a middle member consisting of mafic lava, volcaniclastic sandstone,and tuff of upper Miocene age(Sutton, 1974; Hackman and Olson, 1977; Ulrich et al., 1984; Damon and Spencer, 2001), and (3) an upper member that consists of fluvial and eolian sand,silt, and clay of uppermost Miocene to Pliocene age (Repenning and Irwin,1954; Repenning et al., 1958;Love, 1989).Although the Bidahochi Formation has beensubdividedinto members, the members are facies with complex depositional relationships(e.g., Kierschand Keller, 1955;Dickinson, 2013). The lower and middle members are completely missing from southern and eastern areas where the upper member rests on Paleozoic and Mesozoic strata (Figure 2).

In the Sanders area the upper, dominantly fluvial member includes bentonite clay deposits(it is not entirely clear that assignment of Bidahochi Formation members is meaningful in this area). The bentonite clay deposits, consisting of calcium montmorillonite and known as the Cheto mine deposits,havebeen exploited fordesiccants, gellants, and acid-activated bentonites since 1924 (Kiersch and Keller, 1955;Eyde and Eyde, 1987). The overlying silts and sands of the upper Bidahochi Formation include sand deposits that contain 93-99% SiO2(Table 1),some of which contain a large fraction of sand in the-20 +40 mesh size that is generally preferred for frac sands (Tables 2-5). Furthermore, the deposits can be mined with a front-end loader, unlike other frac-sand deposits in Texas and elsewhere that must be mined and processed by blasting and crushing (Eyde and Eyde, 1987).

The Preferred Sands plant and quarry (Figure 3) were active in 2015, with employment of 53 workers according to the U.S. Department of Labor (http://www.msha.gov/drs/drshome.htm). Employment reached 95 workers in2012 (actually “sum of average employment” based on hours worked as reported to the USDOL). The quarry operations are located largely at the site of the former Cheto bentonite quarries. Arizona Silica Sand Company was engaged in sand production at Houck through 2011according to the Arizona Mine Inspector’s annual report. However, the Houck silica sand plant and quarry (Figure 3) appeared from aerial imagery to be inactive, and a search of the U.S. Department of Labor web site yielded no information using the search terms “Arizona Silica”, “Houck Silica” and“Houck”.

Lower Colorado River Valley

Sand dunes are exposed over large areas in the Yuma Desert southeast of Yuma and at Cactus Plain southeast of Parker (Figure 1). In both areas sands deposited in the Colorado River Valley by the Colorado River have been displaced by winds and redeposited in sand dunes. Chemical analysis of dune sands from Cactus Plain near Parker and the Algodones Dunesin the Yuma desert near Yuma indicate silica content primarily in the 80-90% range, with none exceeding 90% (Zimbelman and Williams, 2002). Analyses of dune sands in the eastern Mojave Desert, west of the Colorado River, indicate silica content of consistently <80%, apparently because these sand deposits are upwind rather than downwind from quartz-rich sands delivered by the Colorado River (Zimbelman and Williams, 2002). Although Cactus Plain and the Algodones Dunes are both near railroad tracks and could be easily quarried, their physical properties are not appropriate for hydraulic fracturing sands because they contain too much feldspar and perhaps because of other factors such as small grain size.

Conclusion

The unusual purity of sand deposits in the upper Bidahochi Formation, containing little but quartz, and the adequate roundness and grain size, have made these deposits attractive for use in hydraulic fracturing. Other deposits in Arizona that could be economically quarried and processed have not been identified. Given the enormous aerial extent of the upper Bidahochi Formation, it seems likely that this area will continue to be exploited for frac sands as long as hydraulic fracturing remains a viable tool for oil and gas extraction.

Reference:
Spencer, J.E., Niemuth, N.J. Silica-sand deposits in Arizona. http://repository.azgs.az.gov/uri_gin/azgs/dlio/1643

Note: The above post is reprinted from materials provided by AZGS Document Repository.

New Sunshine State Maps Add U.S. Forest Service Data

Updated 2015 version of the Spring Creek US Topo quadrangle with orthoimage turned on. (1:24,000 scale)

Recently released US Topo maps for Florida now feature more trails using data provided by the U.S. Forest Service as well as trail information from other federal, state and private sources.

Several of the 1,028 new US Topo quadrangles for Florida now display parts of the Florida National Scenic Trail (FNST) and other designated public trails. For Gulf Coast residents, recreationalists and visitors who want to explore the featured Florida trails by biking, hiking, horseback or other means, the new trail features on the US Topo maps will be useful.

The FNST is a congressionally-designated, long-distance hiking trail that weaves its way across more than 1,000 miles of Florida from Big Cypress National Preserve in the south to Gulf Islands National Seashore in the western end of Florida’s panhandle. The Trail is a national treasure, being one of only 11 National Scenic Trails in the country, and one of three contained entirely within a single state.

“As administrators of the Florida National Scenic Trail, we work with a variety of partners to ensure that the trail is managed, and interpreted, consistently across changing landscapes and management boundaries,” said Shawn Thomas, Florida National Scenic Trail Program Manager. “Illustrating the FNST on the widely accessible US Topo maps will not only further this management purpose, but allow more recreationists and potential resource stewards to learn about the Florida National Scenic Trail and enjoy the natural, scenic, cultural, and historical resources the Trail corridor has to offer.”

The USGS partnered with the U.S. Forest Service to incorporate the trail data onto the revised Florida US Topo maps. The Florida National Scenic Trail, joins the Appalachian National Scenic Trail, Arizona National Scenic Trail, Continental Divide National Scenic Trail, Ice Age National Scenic Trail, Natchez Trace National Scenic Trail, New England National Scenic Trail, North Country National Scenic Trail, Pacific Crest National Scenic Trail, and the Pacific Northwest National Scenic Trail, as being featured on the new US Topo quads. The USGS plans to eventually include all National Scenic Trails in The National Map products.

The U.S. Forest Service has provided boundary and road data for the US Topo map series for the past five years, and is now working on a national dataset of recreational trails.

Some of the other data for new trails on the maps is provided to the USGS through a nationwide “crowdsourcing” project managed by the International Mountain Biking Association (IMBA).  This unique crowdsourcing venture has increased the amount and diversity of trail data available through The National Map mobile and web apps, and the revised US Topo maps.

During the past two years the IMBA, in a partnership with the MTB Project, has been building a detailed national database of trails. This activity allows local IMBA chapters, IMBA members, and the public to provide trail data and descriptions through their website. MTB Project and IMBA then verify the quality of the trail data provided, ensure accuracy and confirm the trail is officially designated for public use.

Further significant additions to the new quadrangles include map symbol redesign, enhanced railroad information and new road source data.

The new 2015 US Topo map coverage over Florida replaces the first edition US Topo maps for the Sunshine State and are available for free download from The National Map, the USGS Map Locator & Downloader website , and several other USGS applications.

To compare change over time, scans of legacy USGS topo maps, some dating back to the late 1800s, can be downloaded from the USGS Historical Topographic Map Collection.

For more information on US Topo maps: http://nationalmap.gov/ustopo/.

Updated 2015 version of the Spring Creek US Topo quadrangle with orthoimage turned off to better show trails. (1:24,000 scale)
Scan of the 1940 legacy topographic map quadrangle of the Spring Creek area (Arran quad, 1:62,500 scale) from the USGS Historic Topographic Map Collection

.

The Florida National Scenic Trail is currently more than 1,000 miles long, with 1,300 total miles planned. The U.S. Forest Service has divided the Trail into four main geographic regions: the Southern region, the Central region, the Northern region, and the Panhandle region.

Note: The above post is reprinted from materials provided by U.S. Geological Survey.

Siberian Traps likely culprit for end-Permian extinction

Around 252 million years ago, life on Earth collapsed in spectacular and unprecedented fashion, as more than 96 percent of marine species and 70 percent of land species disappeared in a geological instant. The so-called end-Permian mass extinction—or more commonly, the “Great Dying”—remains the most severe extinction event in Earth’s history.

Scientists suspect that massive volcanic activity, in a large igneous province called the Siberian Traps, may have had a role in the global die-off, raising air and sea temperatures and releasing toxic amounts of greenhouse gases into the atmosphere over a very short period of time. However, it’s unclear whether magmatism was the main culprit, or simply an accessory to the mass extinction.

MIT researchers have now pinned down the timing of the magmatism, and determined that the Siberian Traps erupted at the right time, and for the right duration, to have been a likely trigger for the end-Permian extinction.

According to the group’s timeline, explosive eruptions began around 300,000 years before the start of the end-Permian extinction. Enormous amounts of lava both erupted over land and flowed beneath the surface, creating immense sheets of igneous rock in the shallow crust. The total volume of eruptions and intrusions was enough to cover a region the size of the United States in kilometer-deep magma. About two-thirds of this magma likely erupted prior to and during the period of mass extinction; the last third erupted in the 500,000 years following the end of the extinction event. This new timeline, the researchers say, establishes the Siberian Traps as the main suspect in killing off a majority of the planet’s species.

“We now can say it’s plausible,” says Seth Burgess, who received his PhD last year from MIT’s Department of Earth, Atmospheric, and Planetary Sciences and is now a postdoc at the U.S. Geological Survey. “The connection is unavoidable, because it’s clear these two things were happening at the same time.”

Burgess and Sam Bowring, the Robert R. Shrock Professor of Earth and Planetary Science at MIT, have published their results in the journal Science Advances.

A singular event

Around the time of the end-Permian extinction, scientists have found that the Earth was likely experiencing a sudden and massive disruption to the carbon cycle, abnormally high air and sea temperatures, and an increasingly acidic ocean—all signs of a huge and rapid addition of greenhouse gases to the atmosphere. Whatever triggered the mass extinction, scientists reasoned, must have been powerful enough to generate enormous amounts of greenhouse gases in a short period of time.

The Siberian Traps have long been a likely contender: The large igneous province bears the remains of the largest continental volcanic event in Earth’s history.

“It’s literally a singular event in Earth history—it’s a monster,” Burgess says. “It makes Yellowstone … look like the head of a pin.”

It’s thought that as the region erupted, magma rose up through the Earth’s crust, essentially cooking sediments along the way and releasing enormous amounts of greenhouse gases like carbon dioxide and methane into the atmosphere.

“The question we tried to answer is, ‘Which came first, mass extinction or the Siberian Traps? What is their overall tempo, and does the timing permit magmatism to be a trigger for mass extinction?'” Burgess says.

Dates pinned

For the answer, Burgess, Bowring, and colleagues traveled to Siberia on multiple occasions, beginning in 2008, to sample rocks from the Siberian Traps. For each expedition, the team traveled by boat or plane to a small Siberian village, then boarded a helicopter to the Siberian Traps. From there, they paddled on inflatable boats down a wide river, chiseling out samples of volcanic rock along the way.

“We’d have a couple of hundred kilos of rocks, and would go to the market in Moscow and buy 15 sport duffle bags, and in each we’d put 10 kilos of rocks … and hope we could get them all on the plane and back to the lab,” Burgess recalls.

Back at MIT, Burgess and Bowring dated select samples using uranium/lead geochronology, in which Bowring’s lab specializes. The team looked for tiny crystals of either zircon or perovskite, each of which contain uranium and lead, the ratios of which they can measure to calculate the rock’s age. The team dated various layers of rock to determine the beginning and end of the eruptions.

They then compared the timing of the Siberian Traps to that of the end-Permian extinction, which they had previously determined using identical techniques.

“That’s important, because we can compare green apples to green apples. If everything is done the same, there’s no bias,” Burgess says. “Now we’re able to say magmatism definitely preceded mass extinction, and we can resolve those two things outside of uncertainty.”

Richard Ernst, a scientist-in-residence at Carleton University in Ottawa, Ontario, says the new timeline establishes a definitive, causal link between the Siberian Traps and the end-Permian extinction.

“This paper nails it,” says Ernst, who was not involved in the study. “Given that they have dated a portion of the Siberian Traps occurring just before, during, and only for a short time after the extinction, this is the ‘smoking gun’ for this large igneous province being fully correlated with the extinction. At this point, additional dating and other studies will simply provide more details on the link.”

Now that the team has resolved the beginning and end of the Siberian Traps eruptions, Burgess hopes others will take an even finer lens to the event, to determine the tempo of magmatism in the 300,000 years prior to the mass extinction.

“We don’t know if a little erupted for 250,000 years, and right before the extinction, boom, a vast amount did, or if it was more slow and steady, where the atmosphere reaches a tipping point, and across that point you have mass extinction, but before that you just have critically stressed biospheres,” Burgess says. “Now we’ve pinned it down in time, and others can go in with other techniques to get a more fully fleshed out timeline. But we need it to start someplace, and that’s what we’ve got.”

This story is republished courtesy of MIT News (web.mit.edu/newsoffice/), a popular site that covers news about MIT research, innovation and teaching.

Note: The above post is reprinted from materials provided by Massachusetts Institute of Technology.

Unlocking secrets of how fossils form

Scientists pieced together 3,600 tiny images of this shrimp fossil to understand the processes that preserved it. Credit: American Chemical Society

Fossils tell amazing stories and inspire them, too — just think of this summer’s “Jurassic World” blockbuster. But because some of the processes that preserve fossils are not well understood, there’s still more information that they could reveal. Now scientists report in ACS’ journal Analytical Chemistry a new way to probe fossils to find out how these ancient remains formed in greater detail than before.

When most organisms die, they biodegrade and leave little behind. But if they get trapped in sediments that harbor few bacteria and loads of dissolved minerals, they can become fossilized and preserved for millions of years. Scientists use a variety of techniques on the ancient specimens to determine details about lifestyles and diets, as well as information about the geographical distribution of the creatures. One of those methods called scanning electron microscopy, or SEM, showed particular promise for revealing new information about fossils. So Amauri J. Paula and colleagues expanded on this method.

The researchers used a large-field SEM approach to analyze a shrimp fossil from the Araripe Basin, a place in northeastern Brazil known among paleontologists as a treasure trove of flying pterosaur remains. The shrimp specimen dates back to the Cretaceous period, when dinosaurs still roamed the planet. The technique provided evidence for the first time that a rare fossilization process occurred in the basin. It also showed that the fossil over millions of years developed a surprising fractal characteristic — a repeating pattern most commonly recognized in snowflakes but also found in structures as large as spiral galaxies.

Note: The above post is reprinted from materials provided by American Chemical Society.

Upslope migration of tropical plants due to climate change

The Chimborazo volcano towers at a height of up to 6,268 meters. In 2012, Danish researchers followed in Humboldt’s footsteps up the mountainsides to study how much the plant species had migrated upslope during the last two centuries. Credit: Naia Morueta-Holme

The plants on the highest mountain in Ecuador have migrated more than 500 meters to higher altitudes during the last two centuries. This is determined in a new study, in which Aarhus University researchers compared Humboldt’s data from 1802 with current conditions.

Although most of the world’s species diversity is found in tropical areas, there are very few studies that have examined whether tropical mountain species are affected by climate change to the same extent as temperate species. A new study has now determined that major changes have taken place during the last two centuries.

By comparing the migration of plant communities on the Chimborazo volcano in Ecuador with historical data from 1802, Aarhus University researchers found an average upslope shift of more than 500 meters. The entire vegetation boundary has moved upwards from 4,600 meters to almost 5,200 meters. The main explanation for this dramatic shift is climate change over the last 210 years.

In Humboldt’s footsteps

The German scientist Alexander von Humboldt traveled to South and Central America around the 1800s to map the distribution of plants and to explore what determines the different vegetation boundaries. He collected plants over a period of many years, and his collections led to a better understanding of the link between climate and species’ distributions, which he described in several works. One of his most noteworthy works was the Physical Tableau, a cross-section of the Chimborazo inscribed with the names of the plants he found on the mountainside.

“Humboldt’s Tableau and the accompanying descriptions make up the oldest known data set in the world of vegetation along elevation gradients. It provided us with a unique opportunity to study how plant distributions have changed in the tropics during the last two centuries,” says Professor Jens-Christian Svenning, Department of Bioscience, Aarhus University, who is one of the authors of the study.

In summer 2012, the team of researchers followed in Humboldt’s footsteps to Chimborazo to map the current distribution of the plants. The fieldwork was carried out at an altitude of up to 5,200 meters.

“Right up at 5,185 meters, we found the last trace of vegetation. A defiant little plant belonging to the sunflower family and half covered in snow — in full flower in spite of the cold conditions, the thin air, and the harsh wind,” says Naia Morueta-Holme, the lead author of the study. The fieldwork was carried out in connection with her PhD studies at the Department of Bioscience, Aarhus University.

Upward shift of vegetation zones

By comparing the two data sets, it became clear that not only the vegetation growth limit has moved, but also the vegetation zones defined by Humboldt. The individual plant species are now found more than 500 meters upslope than they were 210 years ago. These changes in the vegetation are more than expected as a result of today’s warmer climate.

Other studies show that there is now less precipitation in the area, which has also contributed to the significant shrinkage of the glaciers covering the top of the volcano. In addition, the lower parts of the volcano have been intensively cultivated, and a number of species that were previously only found in the lowland near agricultural areas have been introduced by humans.

A combination of human-induced climate change and the direct impact on the plant communities via cultivation of the landscape around the volcano helps explain the large-scale vegetation shift — more than has been experienced in other regions outside the tropics.

Provides insight into the future

The study shows how historical data sets can be used to demonstrate the way nature is already shifting in response to global and local environmental change. This provides insight into what to expect in the future, when climate change is forecast to be even more severe than witnessed in the last two centuries.

“Even though the plants have kept up on average until now, we see many individual species that are lagging behind, while others — especially common species that are good at spreading and living under many different conditions — are moving upslope. We can thus expect even more drastic changes in the vegetation in the future, and there are concerns about how the rare and specialized species will survive — particularly in the tropics, where most of them grow,” explains Naia Morueta-Holme.

The results of the study can be used for purposes such as nature conservation by giving high priority to efforts to minimize the direct impact of landscape cultivation.

Reference:
Naia Morueta-Holme, Kristine Engemann, Pablo Sandoval-Acuña, Jeremy D. Jonas, R. Max Segnitz, Jens-Christian Svenning. Strong upslope shifts in Chimborazo’s vegetation over two centuries since Humboldt. Proceedings of the National Academy of Sciences, 2015; 201509938 DOI: 10.1073/pnas.1509938112

Note: The above post is reprinted from materials provided by Aarhus University.

Scientists use lasers to simulate shock effects of meteorite impact on silica

Meteor Crater in Arizona, formed by a meteorite impact 50,000 years ago, contains bits of a hard, compressed form of silica called stishovite. Researchers precisely measured the rapid transformation of a fused silica glass into stishovite using SLAC’s X-ray laser, the Linac Coherent Light Source. Credit: National Map Seamless Server/USGS

Scientists used high-power laser beams at the Department of Energy’s SLAC National Accelerator Laboratory to simulate the shock effects of a meteorite impact in silica, one of the most abundant materials in Earth’s crust. They observed, for the first time, its shockingly fast transformation into the mineral stishovite — a rare, extremely hard and dense form of silica.

You can scoop up bits of stishovite at the scene of meteorite impacts, such as a 50,000-year-old meteor crater in Arizona that measures about 3/4-mile across and about 570 feet deep. A similar form also exists naturally at the extreme pressures of Earth’s mantle, hundreds of miles below ground.

The Speed of Stishovite

In the experiment at SLAC, researchers used lasers to create a shock wave in samples of silica glass. The heat and compression of this shock wave caused tiny crystals, or “grains,” of stishovite to grow within just a few nanoseconds, or billionths of a second. This speed defies predictions that the changes take tens or even hundreds of times longer.

“The beauty here is that the quality of the data enabled us to make a measurement that gives us entirely new insight into the mechanism for this transformation,” said Arianna Gleason, who led the experiment at SLAC’s Linac Coherent Light Source (LCLS) X-ray laser, a DOE Office of Science User Facility. The work was published in the Sept. 4 issue of Nature Communications.

“Figuring out how atoms rearrange themselves in this material is important, and to our great surprise, what we expected to be a slower process is really rapid,” said Gleason, who was a postdoctoral researcher at SLAC and Stanford University at the time of the 2012 experiment and is now a postdoctoral fellow at Los Alamos National Laboratory. “That was not known before. LCLS gave us access to this ultrashort timescale combined with the capability to generate a shockwave, which is unique.”

New Insight in Planetary, Materials Science

The improved understanding gives researchers new insight about the basic properties of silica and other materials, and could ultimately lead to improved models of planetary formation and composition and new approaches for designing future materials with improved functionality, such as strength.

In the LCLS experiment, researchers aimed two optical laser pulses at the same point on the silica samples. They used brilliant, ultrashort X-ray pulses produced by LCLS to explore the resulting shock effects on a timescale of femtoseconds and from an atom’s-eye view. They varied the arrival time of the X-ray pulses to pinpoint the speed of the material’s transformation.

Creating stishovite with laser light: The whitish bands that appear in this compiled sequence of X-ray-produced images allow scientists to identify the ultrafast emergence of the mineral stishovite after shocking samples of fused silica with a high-power laser. The time-delay in this sequence is measured in nanosceconds (“ns”). Credit: Arianna Gleason/Los Alamos National Laboratory

Previous experiments, including high-compression experiments that squeezed samples between diamonds, lacked the ultrafast timescales and the atomic-level resolution made possible by LCLS X-rays.

Researchers have since conducted follow-up experiments that explore other shock properties in this and other materials, including metals and semiconductors heavily used in industry.

“We’re really just scratching the surface of being able to visualize transformations during shock compression in real time via snapshots with LCLS, and in understanding the states of materials in the interior of our own planet and other planets,” said Gleason.

Reference:
A. E. Gleason, C. A. Bolme, H. J. Lee, B. Nagler, E. Galtier, D. Milathianaki, J. Hawreliak, R. G. Kraus, J. H. Eggert, D. E. Fratanduono, G. W. Collins, R. Sandberg, W. Yang, W. L. Mao. Ultrafast visualization of crystallization and grain growth in shock-compressed SiO2. Nature Communications, 2015; 6: 8191 DOI: 10.1038/ncomms9191

Note: The above post is reprinted from materials provided by SLAC National Accelerator Laboratory.

New Flea Genus and Species Found in 20-million-year-old Amber

This is a lateral view of Atopopsyllus cionus. Credit: George Poinar, Jr.

Dr. George Poinar, Jr., an entomologist from Oregon State University, has found a fossilized flea the like of which he has never seen. Its basic characteristics are so strange, he says, that it deserves its own genus. And in fact, the name of the genus he has applied to the insect, Atopopsyllus, means “strange flea” in Greek.

Dr. Poinar describes the insect, which he believes is 20-30 million years old, in the latest issue of the Journal of Medical Entomology.

The flea’s most notable unusual features, according to Dr. Poinar, are ones “that I cannot find on any other flea, fossil or extant.”

One strange feature is that it has five-segmented maxillary palps.

“Normally fleas have four-segmented maxillary palps,” Poinar said.

Another feature that caught Poinar’s eye is a structure similar to cerci.

“I couldn’t find anything like that in present-day fleas except in the female,” he said. “That fascinated me, that this male would have a structure similar to that. I don’t know if it’s homologous. All I can say is that it’s there, it’s in the same place that the female’s structure is.”

The cerci are found at the insect’s rear, and the specific epithet of the new flea, Atopopsyllus cionus, recognizes this feature. Cionus is from the Greek “kion” or “pillar,” which refers to the organ found on the flea.

The specimen also shows the connection between insects and pathogenic microorganisms. In addition to the flea’s unusual morphology, Poinar was struck by the microorganisms found in the flea, which is embedded in amber from the West Indies.

“I’ve spent a lot of time looking for pathogens that are vectored by insects in amber,” he said. “I was quite excited when we found pathogens inside the flea in the anal area. We found bacteria that have the characteristics of plague bacteria. We can’t say they’re plague bacteria. All we can say is their morphology is similar to that which is shown to be associated with plague.”

He also found trypanosomes in the specimen.

“So we know that this flea was vectoring at least two pathogens,” he said. “It shows that even back at that time, pathogens were established in fleas in the West Indies. They could have affected rodents because we found rodent hair in the amber. This shows the antiquity of the relationship between vector, host, and pathogen.”

The specimen was actually discovered by Poinar’s wife Roberta while the two of them were going though a collection of amber at their lab at the University of California, Berkeley (before they moved to Oregon). Stimulated by the discovery of this flea, Poinar says that he and his wife will try to find more samples of Atopopsyllus cionus in the future.

Reference:
“A New Genus of Fleas with Associated Microorganisms in Dominican Amber” . DOI: 10.1093/jme/tjv134

Note: The above post is reprinted from materials provided by Entomological Society of America.

New perspectives for long-term climate predictions

This image shows a time series of solar activity (bottom) and the North Atlantic Oscillation in two model simulations, without (blue) and with (yellow) solar forcing. Credit: Graphics, GEOMAR.

Are climate predictions over periods of several years reliable if weather forecast are still only possible for short periods of several days? Nevertheless there are options to predict the development of key parameters on such long time scales. A new study led by scientists at GEOMAR Helmholtz Centre for Ocean Research Kiel shows how the well-known 11-year cycle of solar activity affects the long-time development of dominant large-scale pressure systems in the Northern Hemisphere.

For their investigations the scientists used a coupled ocean-atmosphere model. In addition, this model includes an interactive chemistry module which can for instance cope with the effect of ultraviolet radiation (UV) in the upper atmosphere. This additional component seemed to be key to transmit the variations in the solar radiation which might have only a small direct impact on Earth’s surface, through a complex mechanism from the stratosphere (10-50 km altitude) to the lower atmosphere.

“We have carried out several experiments,” says Dr. Rémi Thiéblemont from GEOMAR, lead author of the study. “We conducted model experiments over a period of 145 years, with and without the influence of solar activity ,” Thiéblemont continued. The sun’s influence could clearly be identified in the so-called North Atlantic Oscillation, which is roughly speaking the pressure difference between the Azores high and the Iceland low. The ratio between these two pressure systems often determines the weather in Europe over longer time periods, such as whether the winter months turn warm and stormy or cold and snowy. The researchers found a time lag between variations in solar irradiance and atmospheric pressure patterns of about one to two years, which can be explained by an interaction between the atmosphere and the ocean. By comparing the two experiments with or without solar activity, they were able to prove for the first time that the sun irradiance serves as a phase-lock for the North Atlantic Oscillation. With this context, an increase of the predictability of the decadal NAO phase can be expected.

“The fact that the circulation in the upper atmosphere responds significantly to the solar fluctuations, is already known,” Prof. Dr. Katja Matthes, initiator and co-author of the study from GEOMAR explains. “On one hand we can demonstrate with this new study how the transmission of the signal to Earth’s surface and its interaction with the ocean works, and on the other hand we can show the importance of the chemical reactions for the coupling,” Prof. Matthes continued. So far, most global climate models have neither a sufficient resolution in the stratosphere nor interactive chemical components. “Although the solar effect on the North Atlantic Oscillation explains only a few percent of the total variance, the close relationship between solar activity and phase North Atlantic Oscillation is an important indicator to improve the predictability of climate variability,” Dr. Thiéblemont summarizes.

There is still a long way to go, for successful and reliable long-term forecasts up to a decade. Nevertheless, for successful predictions it is important to include solar fluctuations, Professor Matthes concludes.

Reference:
Rémi Thiéblemont, Katja Matthes, Nour-Eddine Omrani, Kunihiko Kodera, Felicitas Hansen. Solar forcing synchronizes decadal North Atlantic climate variability. Nature Communications, 2015; 6: 8268 DOI: 10.1038/ncomms9268

Note: The above post is reprinted from materials provided by Helmholtz Centre for Ocean Research Kiel (GEOMAR).

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