WFS News: A method for rapid 3D scanning and replication of large paleontological specimens

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Citation: Das AJ, Murmann DC, Cohrn K, Raskar R (2017) A method for rapid 3D scanning and replication of large paleontological specimens. PLoS ONE 12(7): e0179264. https://doi.org/10.1371/journal.pone.0179264

Editor: Pasquale Raia, Seconda Universita degli Studi di Napoli, ITALY

Scanning technique. (a) Small section, high resolution scanning. The user holds a monopod mounted Kinect at close range (0.5–1.5 m) from the target. (b) Large section or complete 360° scanning. The user mounts Kinect on a body supported rig and walks around the artifact (1.5–4.5 m from target) to complete the scan. Sketch by Francis Goeltner.

Scanning technique.(a) Small section, high resolution scanning. The user holds a monopod mounted Kinect at close range (0.5–1.5 m) from the target. (b) Large section or complete 360° scanning. The user mounts Kinect on a body supported rig and walks around the artifact (1.5–4.5 m from target) to complete the scan. Sketch by Francis Goeltner.

The field of paleontology has transformed in the last few years as a result of the developments in 3D scanning technology and rendering software that have enhanced the quality of virtual models [14]. Conventionally, a photograph is utilized for research purposes which has its benefits but also has limited application. A two dimensional (2D) image is easy to capture, interpret and is still a useful method of analysis in paleontology research [57]. However, a 2D image cannot capture the details regarding depth of the scene. Recent studies have shown that 3D scanning and analysis of specimens can provide rich information which can be beneficial in a range of studies [8]. These techniques are increasingly seen in museums and research labs due to the compact nature of some of the imaging devices [34]. 3D scanning can provide depth maps in a non-invasive, non-contact manner which is attractive for studying paleontological specimens due to their delicate physical properties. For instance, it has been used to estimate the mass of dinosaurs by combining it with computer modeling [9]. It has also been used to create virtual skeletons for different fauna for comparative purposes [10]. Other examples of 3D scanning in related fields include typology [11], pottery studies [12] and footprint analysis in archaeology [13].

At the heart of 3D imaging technology is the 3D scanner itself. There are several approaches to perform 3D scanning from structured light scanners to computed tomography (CT). However, most of these scanners are industrial or clinical grade instruments and are generally very expensive and bulky. Structured light scanners need calibration and are inherently expensive due to the requirement of a laser projector and a high end camera to capture the images. There are reports of using structured light based 3D scanning for fossils of the size of several tens of centimeters [14] but not large specimens like T.rex skulls [10]. Several other reports have demonstrated the use of CT imaging due to its ability to study internal details of specimens. However, CT scanners are expensive and the imaging is done at a clinical facility [1516]. Additionally, most studies have used these techniques on small specimens due to the complexity of the scanner and also restriction of the data size that can be handled by the software for large specimens. For instance, a high resolution dental scanner would not be able to handle the large data size when scanning the jaw of a T.rex. Hence, there are limitations in the volume of the object that can be scanned with these methods, the ease of setup and processing the data. Furthermore, the software for these industrial scanners is proprietary making it inaccessible to researchers and museums. Although there have been some reports on the use of free open source photogrammetric software for 3D imaging, the process is cumbersome requiring a large amount of data to reconstruct the models [17]. Hence there is a need for a technique that is accurate, low-cost, easy to implement, has open source software capability and can be adapted for large scale paleontological scanning.

We propose a new technique that provides high quality 3D reconstructions of large specimens with relative ease. We used the Kinect v2 TOF sensor to perform 3D scanning of large paleontological specimens for the first time. Kinect has traditionally been used in gesture recognition [1820] in gaming, computer graphics [21] and more recently in 3D scanning [2224]. There has been one earlier report that used Kinect v1 for paleontological specimens but the reconstructions were noisy and smoothing the data resulted in loss of features [14]. Kinect v1 uses structured light imaging in contrast to Kinect v2 that is based on TOF imaging which has significantly improved since the report by Falkingham [14]. The sensor technology in Kinect v2 is not only superior to Kinect v1 but also the computation aspect has improved providing real-time high quality reconstructions. The Kinect has shown to be a promising tool for full body scanning with improvements in registration and alignment techniques [25]. Most of the earlier demonstrations have been performed on rotating objects where the Kinect is stationary. However, this may not be possible for large paleontological specimens that are housed in enclosures that cannot be modified.

In this report, we present a method for 3D scanning that is well suited for paleontology and has the following advantages; a) It has an short acquisition time of 60-120s even for large specimens, b) Since the scanner is compact so it can be moved around the specimen on a tripod or adapted to a body-mounted wearable geometry; c) The entire set-up being low-cost and the availability of free scanning and post-processing software.

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WFS News: Two-billion-year-old evaporites capture Earth’s great oxidation.

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A 2-billion-year-old chunk of sea salt provides new evidence for the transformation of Earth’s atmosphere into an oxygenated environment capable of supporting life as we know it.

The study by an international team of institutions including Princeton University found that the rise in oxygen that occurred about 2.3 billion years ago, known as the Great Oxidation Event, was much more substantial than previously indicated.

“Instead of a trickle, it was more like a firehose,” said Clara Blättler, a postdoctoral research fellow in the Department of Geosciences at Princeton and first author on the study, which was published online by the journal Science on Thursday, March 22. “It was a major change in the production of oxygen.”

A sample of 2-billion-year-old salt (pink-white recrystallized halite) with embedded fragments of calcium sulfate from a geological drill core in Russian Karelia. Credit: Photo by Aivo Lepland, Geological Survey of Norway; courtesy of Science/AAAS

A sample of 2-billion-year-old salt (pink-white recrystallized halite) with embedded fragments of calcium sulfate from a geological drill core in Russian Karelia.
Credit: Photo by Aivo Lepland, Geological Survey of Norway; courtesy of Science/AAAS

The evidence for the profound upswing in oxygen comes from crystalized salt rocks extracted from a 1.2-mile-deep hole in the region of Karelia in northwest Russia. These salt crystals were left behind when ancient seawater evaporated, and they give geologists unprecedented clues to the composition of the oceans and atmosphere on Earth more than 2 billion years ago.

The key indication of the increase in oxygen production came from finding that the mineral deposits contained a surprisingly large amount of a component of seawater known as sulfate, which was created when sulfur reacted with oxygen.

“This is the strongest ever evidence that the ancient seawater from which those minerals precipitated had high sulfate concentrations reaching at least 30 percent of present-day oceanic sulfate as our estimations indicate,” said Aivo Lepland, a researcher at the Geological Survey of Norway, a geology specialist at Tallinn University of Technology, and senior author on the study. “This is much higher than previously thought and will require considerable rethinking of the magnitude of oxygenation of Earth’s 2-billion year old atmosphere-ocean system.”

Oxygen makes up about 20 percent of air and is essential for life as we know it. According to geological evidence, oxygen began to show up in the Earth’s atmosphere between 2.4 and 2.3 billion years ago.

Until the new study, however, geologists were uncertain whether this buildup in oxygen — caused by the growth of cyanobacteria capable of photosynthesis, which involves taking in carbon dioxide and giving off oxygen — was a slow event that took millions of years or a more rapid event.

“It has been hard to test these ideas because we didn’t have evidence from that era to tell us about the composition of the atmosphere,” Blättler said.

The recently discovered crystals provide that evidence. The salt crystals collected in Russia are over a billion years older than any previously discovered salt deposits. The deposits contain halite, which is called rock salt and is chemically identical to table salt or sodium chloride, as well as other salts of calcium, magnesium and potassium.

Normally these minerals dissolve easily and would be washed away over time, but in this case they were exceptionally well preserved deep within the Earth. Geologists from the Geological Survey of Norway in collaboration with the Karelian Research Center in Petrozavodsk, Russia, recovered the salts from a drilling site called the Onega Parametric Hole (OPH) on the western shores of Lake Onega.

The unique qualities of the sample make them very valuable in piecing together the history of what happened after the Great Oxidation Event, said John Higgins, assistant professor of geosciences at Princeton, who provided interpretation of the geochemical analysis along with other co-authors.

“This is a pretty special class of geologic deposits,” Higgins said. “There has been a lot of debate as to whether the Great Oxidation Event, which is tied to increase and decrease in various chemical signals, represents a big change in oxygen production, or just a threshold that was crossed. The bottom line is that this paper provides evidence that the oxygenation of the Earth across this time period involved a lot of oxygen production.”

The research will spur the development of new models to explain what happened after the Great Oxidation Event to cause the accumulation of oxygen in the atmosphere, Blättler said. “There may have been important changes in feedback cycles on land or in the oceans, or a large increase in oxygen production by microbes, but either way it was much more dramatic than we had an understanding of before.”

  1. C. L. Blättler, M. W. Claire, A. R. Prave, K. Kirsimäe, J.A. Higgins, P. V. Medvedev, A. E. Romashkin, D. V. Rychanchik, A. L. Zerkle, K. Paiste, T. Kreitsmann, I. L. Millar, J. A. Hayles, H. Bao, A. V. Turchyn, M. R. Warke, A. Lepland. Two-billion-year-old evaporites capture Earth’s great oxidationScience, 2018; eaar2687 DOI: 10.1126/science.aar2687
Princeton University. “Two-billion-year-old salt rock reveals rise of oxygen in ancient atmosphere.” ScienceDaily. ScienceDaily, 22 March 2018. <www.sciencedaily.com/releases/2018/03/180322150306.htm>.

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WFS News: Baby tyrannosaur fossil unearthed in Montana

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For now, there are just a few things researchers and students at the University of Kansas want people to dig about the new dinosaur they recently excavated in Montana’s Hell Creek Formation.

Back at the lab, the researchers found the fossil glowed under a black light. Credit: University of Kansas Read more at: https://phys.org/news/2018-03-baby-tyrannosaur-fossil-unearthed-montana.html#jCp

Back at the lab, the researchers found the fossil glowed under a black light. Credit: University of Kansas
Read more at: https://phys.org/news/2018-03-baby-tyrannosaur-fossil-unearthed-montana.html#jCp

Careful, microscopic preparation of its fragile bones is beginning to reveal important information that will help unravel the life history of Tyrannosaurus rex.

Other young tyrannosaur specimens have been recovered over the years, but since animal skeletons change shape as they grow, some confusion as to their evolutionary relationships has ensued. Some paleontologists think the young ones may represent different species, while other workers have suggested they all represent different growth stages of one species—Tyrannosaurus rex.

KU’s new specimen has the information that may provide the deciding factor of which theory is correct.

Researchers believe the specimen is a young Tyrannosaurus rex but are still conducting their analysis to be sure. They expect to publish their findings in the coming months.

“The teeth suggest it’s a Tyrannosaurus rex; however, there is still more work to be done,” said David Burnham, preparator of vertebrate paleontology at the KU Biodiversity Institute. “Because a young T. rex is so rare, there are only a few that have been found over the years, so it’s difficult to discern what are changes due to growth or if the differences in the bones reflect different species. Fortunately, KU has an older T. rex to compare with and another young T. rex on loan to help decipher this problem.”

One possibility is the specimen represents another carnivorous dinosaur dubbed a Nanotyrannus that likewise was discovered in the Hell Creek Formation and described by other scientists. The Nanotyrannus is a subject of controversy because it may represent a separate species, or it may be a juvenile Tyrannosaurus rex.

“Confusing the issue here is age,” Burnham said. “Ontogeny, that’s the process of growth—and during that process we change. Adult dinosaur bones, especially in the skull, don’t look the same as their younger selves. So, if someone finds a baby or juvenile fossil they may think it’s a new species, but we have to be careful since it may represent a younger growth stage of an existing . It’s reasonable to assume Nanotyrannus could be valid—but we must show it’s not just a stage in the life history of T. rex.”

Source: Article By  Brendan M. Lynch, University of Kansas

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WFS News: EVIDENCE OF NEOTECTONIC ACTIVITY ALONG THE EAST COAST OF INDIAN PENINSULA

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EVIDENCE OF NEOTECTONIC ACTIVITY ALONG THE EAST COAST OF INDIAN PENINSULA ( Riffin T Sajeev

Geological Society of America Abstracts with Programs.doi: 10.1130/abs/2017AM-293786,Volume 49,Issue 6,Pages
388 T219. Challenges in Tectonics:Publisher:Geological Society of America (GSA) :https://gsa.confex.com/gsa/2017AM/meetingapp.cgi/Paper/293786
Abstract:

The eastern coastal plains of the Indian peninsula are studied meagerly based on its tectonic aspects. In the previous ventures, the author reported the paleochronological existence of a large estuary, on the basis of fossils of Crassostrea Sp. Dating back to the mio-pliocene Epoch. The author suggests that the paleo-estuary ceased in existence due to a marine regression caused by a regional uplift in between the present day trajectories of the rivers Thamirabharani and Nambiar. The natures of structural characteristics seen in the regional outcrops of the basin indicate a dominant neotectonic feature. Brittle slip faults are abundant in these rocky outcrops containing Khondalite beds. Shearing is visible almost anywhere. This may be caused by the near proximity of the study area with the Achankovil Shear Zone (AKSZ). A second look at the trajectories of the rivers and drainage mentioned above and the structural features on the outcrops indicate that the uplift is neotectonically induced rather than shear induced.During site exploration, the author found rocks of volcanic origin distributed randomly over the study area. Till this date, the geological community had approached volcanic/ neo tectonic activities in this area only through speculations without any physical, visible evidence. The presences of chunks of volcanic rocks are an acute visual evidence of an event of volcanic nature. Through this study, the author aims to analyze the extent of uplift and its impact on the drainage systems of the rivers on its either side and their divide migration possibilities. The neotectonic aspects of the region are analyzed and any solid evidence of active volcanism is collected and studied. The study is primarily aimed to report the existence of neotectonic activity in the south eastern coast of India.

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WFS facts: dating of fossils

Radioactive dating

Radioactive dating

For example if you have a fossil trilobite and it was found in the Wheeler Formation. The Wheeler Formation has been previously dated to approximately 507 million year old, so we know the trilobite is also about 507 million years old. But, how can we determine how old a rock formation is, if it hasn’t previously been dated?

Scientists can use certain types of fossils referred to as index fossils to assist in relative dating via correlation. Index fossils are fossils that are known to only occur within a very specific age range. Typically commonly occurring fossils that had a widespread geographic distribution such as brachiopods, trilobites, and ammonites work best as index fossils. If the fossil you are trying to date occurs alongside one of these index fossils, then the fossil you are dating must fall into the age range of the index fossil.

Sometimes multiple index fossils can be used. In a hypothetical example, a rock formation contains fossils of a type of brachiopod known to occur between 410 and 420 million years. The same rock formation also contains a type of trilobite that was known to live 415 to 425 million years ago. Since the rock formation contains both types of fossils the ago of the rock formation must be in the overlapping date range of 415 to 420 million years.

Studying the layers of rock or strata can also be useful. Layers of rock are deposited sequentially. If a layer of rock containing the fossil is higher up in the sequence that another layer, you know that layer must be younger in age. If it is lower in sequence it’s of a younger age. This can often be complicated by the fact that geological forces can cause faulting and tilting of rocks.

Absolute dating is used to determine a precise age of a rock or fossil through radiometric dating methods. This uses radioactive minerals that occur in rocks and fossils almost like a geological clock. It’s often much easier to date volcanic rocks than the fossils themselves or the sedimentary rocks they are found in. So, often layers of volcanic rocks above and below the layers containing fossils can be dated to provide a date range for the fossil containing rocks.

The atoms in some chemical elements have different forms, called isotopes. These isotopes break down at a constant rate over time through radioactive decay. By measuring the ratio of the amount of the original (parent) isotope to the amount of the (daughter) isotopes that it breaks down into an age can be determined.

We define the rate of this radioactive decay in half-lives. If a radioactive isotope is said to have a half-life of 5,000 years that means after 5,000 years exactly half of it will have decayed from the parent isotope into the daughter isotopes. Then after another 5,000 years half of the remaining parent isotope will have decayed.

While people are most familiar with carbon dating, carbon dating is rarely applicable to fossils. Carbon-14, the radioactive isotope of carbon used in carbon dating has a half-life of 5730 years, so it decays too fast. It can only be used to date fossils younger than about 75,000 years. Potassium-40 on the other hand has a half like of 1.25 billion years and is common in rocks and minerals. This makes it ideal for dating much older rocks and fossils.

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WFS News:60-year-old paleontological mystery of a ‘phantom’ dicynodont

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A new study has re-discovered fossil collections from a 19th century hermit that validate ‘phantom’ fossil footprints collected in the 1950s showing dicynodonts coexisting with dinosaurs.

Before the dinosaurs, around 260 million years ago, a group of early mammal relatives called dicynodonts were the most abundant vertebrate land animals. These bizarre plant-eaters with tusks and turtle-like beaks were thought to have gone extinct by the Late Triassic Period, 210 million years ago, when dinosaurs first started to proliferate. However, in the 1950s, suspiciously dicynodont-like footprints were found alongside dinosaur prints in southern Africa, suggesting the presence of a late-surviving phantom dicynodont unknown in the skeletal record. These “phantom” prints were so out-of-place that they were disregarded as evidence for dicynodont survival by paleontologists. A new study has re-discovered fossil collections from a 19th century hermit that validate these “phantom” prints and show that dicynodonts coexisted with early plant-eating dinosaurs. While this research enhances our knowledge of ancient ecosystems, it also emphasizes the often-overlooked importance of trace fossils, like footprints, and the work of amateur scientists.

This is a skeleton of the dicynodont Placerias, a close relative of the newly-discovered Pentasaurus, with dicynodont trackways (Pentasauropus). Credit: Christian Kammerer

This is a skeleton of the dicynodont Placerias, a close relative of the newly-discovered Pentasaurus, with dicynodont trackways (Pentasauropus).Credit: Christian Kammerer

“Although we tend to think of paleontological discoveries coming from new field work, many of our most important conclusions come from specimens already in museums,” says Dr. Christian Kammerer, Research Curator of Paleontology at the North Carolina Museum of Natural Sciences and author of the new study.

The re-discovered fossils that solved this mystery were originally collected in South Africa in the 1870s by Alfred “Gogga” Brown. Brown was an amateur paleontologist and hermit who spent years trying, with little success, to interest European researchers in his discoveries. Brown had shipped these specimens to the Natural History Museum in Vienna in 1876, where they were deposited in the museum’s collection but never described.

“I knew the Brown collections in Vienna were largely unstudied, but there was general agreement that his Late Triassic collections were made up only of dinosaur fossils. To my great surprise, I immediately noticed clear dicynodont jaw and arm bones among these supposed ‘dinosaur’ fossils,” says Kammerer. “As I went through this collection I found more and more bones matching a dicynodont instead of a dinosaur, representing parts of the skull, limbs, and spinal column.” This was exciting — despite over a century of extensive collection, no skeletal evidence of a dicynodont had ever been recognized in the Late Triassic of South Africa.

Before this point, the only evidence of dicynodonts in the southern African Late Triassic was from questionable footprints: a short-toed, five-fingered track named Pentasauropus incredibilis (meaning the “incredible five-toed lizard foot”). In recognition of the importance of these tracks for suggesting the existence of Late Triassic dicynodonts and the contributions of “Gogga” Brown in collecting the actual fossil bones, the re-discovered and newly described dicynodont has been named Pentasaurus goggai (“Gogga’s five-[toed] lizard”).

“The case of Pentasaurus illustrates the importance of various underappreciated sources of data in understanding prehistory,” says Kammerer. “You have the contributions of amateur researchers like ‘Gogga’ Brown, who was largely ignored in his 19th century heyday, the evidence from footprints, which some paleontologists disbelieved because they conflicted with the skeletal evidence, and of course the importance of well-curated museum collections that provide scientists today an opportunity to study specimens collected 140 years ago.”

A video about this new research can be found here: https://savetubevideo.com/?v=BrdwIQKPCHY

 

Journal reference:Christian F. Kammerer. The first skeletal evidence of a dicynodont from the lower Elliot Formation of South Africa. Palaeontologia Africana, 2018

North Carolina Museum of Natural Sciences. “60-year-old paleontological mystery of a ‘phantom’ dicynodont.” ScienceDaily. ScienceDaily, 14 March 2018. <www.sciencedaily.com/releases/2018/03/180314092330.htm>.

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WFS News: Five New Fossil Forests Found in Antarctica

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Antarctica is one of the harshest environments on the planet. As the coldest, driest continent, it harbors a world of extremes. The powerful katabatic winds that rush from the polar plateau down the steep, vertical drops around the continent’s coast can stir up turbulent snowstorms lasting days or weeks, and the endlessly barren terrain gives Antarctica the title of the world’s largest desert.

Today, polar summers pound the continent with 24 unforgiving hours of light for about half the year, before polar winters plunge it into complete darkness for the other half. Regardless of the season, the temperatures are consistently below freezing, making treks to the landmass unthinkable for the faint of heart.

Scientist Patricia Ryberg returns to Graphite Peak camp after a day collecting fossils on nearby outcrops of rock. The team spent nine days here, living in small mountain tents, and exploring the surrounding terrain between storms. PHOTOGRAPH BY DANNY UHLMANN

Scientist Patricia Ryberg returns to Graphite Peak camp after a day collecting fossils on nearby outcrops of rock. The team spent nine days here, living in small mountain tents, and exploring the surrounding terrain between storms.PHOTOGRAPH BY DANNY UHLMANN

But Antarctica wasn’t always like this. Hundreds of millions of years ago, the continent was smushed together with other modern-day landmasses to form the supercontinent Gondwana. Gondwana was humid and carpeted with a network of hardy plants. As the turbulent climate shifted from hot to cold on a sometimes monthly basis, the streamlined foliage would have needed to withstand extremes.

But then, a massive extinction event pulsed through the land. It catapulted nearly all life to an end, obliterating more than 90 percent of the world’s species at the time.

On the flanks of Graphite Peak, Rudolph Serbet uncovers a 250 million- year-old fossilized tree stump. PHOTOGRAPH BY DANNY UHLMANN

On the flanks of Graphite Peak, Rudolph Serbet uncovers a 250 million- year-old fossilized tree stump.PHOTOGRAPH BY DANNY UHLMANN

What caused this die-off, called the Permian extinction or the Great Dying, is still shrouded in mystery. Clues to the massacre come to us in the form of fossilized trees, but much of the reasons behind this extinction remain unsolved. And that’s why a handful of intrepid scientists traveled to Antarctica this winter, curious to uncover clues about what led to the end of the continent’s forested past.

“Our goal this year was to study fossil ecosystems around the time of the late Permian,” says Erik Gulbranson, a University of Wisconsin-Milwaukee professor who was one of three team leaders on an expedition to the continent in late 2017. “What we’re able to see in these fossil ecosystems is something we’ve never seen before in Antarctica.”

A fallen, fossilized log sits entombed in a bed of sandstone on the flanks of Graphite Peak. PHOTOGRAPH BY DANNY UHLMANN

A fallen, fossilized log sits entombed in a bed of sandstone on the flanks of Graphite Peak.
PHOTOGRAPH BY DANNY UHLMANN

 The team discovered five new fossil forests that would have lived into and beyond the Permian extinction interval. This was the most fossil forests they have found in one season, and it nearly doubles the known fossil forests in Antarctica.

“These new findings tell us how these organisms were reacting or responding to the climatic or environmental changes that were taking place during the extinction crisis,” Gulbranson says. “Having a fossil record of the extinction interval is our only understanding of how life on the planet goes through such an event.”

This work is timely, since many scientists warn that we’re going through an extinction period right now, spurred by human disruptions to natural systems.

MAKING THE TREK

What we know about the Permian extinction we know through marine fossils of animals that once lived in the oceans. Many scientists agree that during this period about 299 to 251 million years ago, a volcanic eventtriggered a crisis that exterminated about 90 percent of all species on the planet. It eradicated more than 95 percent of marine species and more than 70 percent of all land species.

But beyond the broad outlines, a number of the details are unclear. Some geologists and paleontologists say the Permian extinction occurred over 15 million years, but others say it lasted 20,000 years—a blink of an eye in the scheme of geologic time.

The team that Gulbranson, along with his colleague John Isbell and the University of Kansas’s Rudolf Serbit, put together has diverse skillsets. There’s Park University biology professor Patricia Ryberg, who studies the anatomy and morphology of paleobotany, or fossilized plants. There’s also Brian Atkinson, a postdoctoral researcher at the University of Kansas who focuses on seed plants from the Cretaceous period, which is after the Permian. Whereas Ryberg had been on three Antarctic expeditions with Gulbranson, Atkinson had never been to Antarctica before. In fact, this was the second time he had camped out in his life.

“Going to Antarctica is like going to another planet,” Atkinson says. “When you’re searching for plant fossils, it’s like traveling through time. This is as exotic as it gets.”

Gulbranson says this expedition was easily one of the most significant and productive field seasons the team has had to date. At the end of November, the seven-person team left for Antarctica. By early December, they flew a Lockheed LC-130 military aircraft to the Shackleton and McGregor glaciers in the middle of the continent. They pitched two camps, setting up one as a base. For the duration of the 21-day trip, they flew between the two sites by helicopter.

“Those [helicopter] blades are one of the scariest things that you can experience up close,” says Atkinson. The scientists had to constantly jump in and out of choppers—whose thumping blades could slice off a limb in a split second. With the closest hospital thousands of miles away, they had to be cautious coming in and out of the aircraft.

NEW FOSSIL FORESTS

Thirty-mile-per-hour winds pounded the team for days, sometimes lasting up to 12 hours at a time. As they were studying rocks and hiking the first camp, the team discovered five new fossil forests that no one knew existed on the continent. They found some fossil remnants at the second site, but nothing as significant as their findings at the first.

The fossilized trees look a lot like the petrified forests of Yellowstone National Park. Before this expedition, science wasn’t sure if the Permian interval was preserved in sedimentary rocks in Antarctica, but the expedition members think the sedimentary succession they discovered happened at the same time as the extinction interval. That means these new fossil forests would have lived into and beyond the extinction event, representing three distinct ecologic niches from 251 million years ago.

This connection between plants and ecosystems during the extinction event hasn’t been seen until now. The team hopes the discovery can give some clues as to how the Permian extinction played out on land. Ancient microbial life may have played an important role, the team suspects.

“I’m trying to put a puzzle together, but I have no reference picture to do it,” Ryberg says.

PUSHING UP PETRIFIED PLANTS

Permian-era plants are like nothing alive today, Ryberg says. She studies a group of foliage in the genus Glossopteris, which is characterized by woody plants dated roughly 300 to 200 million years ago. The fossil record tells us that Glossopteris plants commonly had tongue-shaped leaves found in thick mats, leading scientists to think they were deciduous.

“Plants are so weird,” Atkinson adds. “There’s a whole lot of different morphologies that you just don’t see in modern plants. The more we get to know these plants, the more weird they become.”

By studying such past changes, scientists hope to get more windows onto the future. There’s time pressure, because conservationists warn that in about 300 years, 75 percent of all mammal species may have disappeared from the planet. By 2060, some say we could see 30 percent of all species go extinct. Whereas other extinction events have been triggered by natural causes, the one we may be in is likely driven by habitat destruction, climate change, and pollution, among other factors.

The Permian extinction may teach us how species react—and adapt—to extinction, Gulbranson says.

For as long as mysteries such as the Great Dying remain, curious scientists will be trekking to remote locations to learn about our planet’s past. This kind of research takes scientific know-how, endurance, and—perhaps most of all—curiosity.

“There’s a certain type of badassness that is required for scientists who want to go to a remote camp in the middle of Antarctica to collect fossils and rock data,” Atkinson says. “I have to go back.”

Source and article : By Photographs by 

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WFS News: Unique diamond impurities indicate water deep in Earth’s mantle

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A UNLV scientist has discovered the first direct evidence that fluid water pockets may exist as far as 500 miles deep into the Earth’s mantle.

Groundbreaking research by UNLV geoscientist Oliver Tschauner and colleagues found diamonds pushed up from the Earth’s interior had traces of unique crystallized water called Ice-VII.

The study, “Ice-VII inclusions in Diamonds: Evidence for aqueous fluid in Earth’s deep Mantle,” was published Thursday in the journal Science.

Rough diamond in kimberlite. (stock image) Credit: © Kacpura / Fotolia

Rough diamond in kimberlite. (stock image)     Credit: © Kacpura / Fotolia

In the jewelry business, diamonds with impurities hold less value. But for Tschauner and other scientists, those impurities, known as inclusions have infinite value, as they may hold the key to understanding the inner workings of our planet.

For his study, Tschauner used diamonds found in China, the Republic of South Africa, and Botswana that surged up from inside Earth. “This shows that this is a global phenomenon,” the professor said.

Scientists theorize the diamonds used in the study, were born in the mantle under temperatures reaching more than 1,000-degrees Fahrenheit.

The mantle — which makes up more than 80 percent of the Earth’s volume — is made of silicate minerals containing iron, aluminum, and calcium among others.

And now we can add water to the list.

The discovery of Ice-VII in the diamonds is the first known natural occurrence of the aqueous fluid from the deep mantle. Ice-VII had been found in prior lab testing of materials under intense pressure. Tschauner also found that while under the confines of hardened diamonds found on the surface of the planet, Ice-VII is solid. But in the mantel, it is liquid.

“These discoveries are important in understanding that water-rich regions in the Earth’s interior can play a role in the global water budget and the movement of heat-generating radioactive elements,” Tschauner said.

This discovery can help scientists create new, more accurate models of what’s going on inside the Earth, specifically how and where heat is generated under the Earth’s crust.

In other words: “It’s another piece of the puzzle in understanding how our planet works,” Tschauner said.

Of course, as it often goes with discoveries, this one was found by accident, explained Tschauner.

“We were looking for carbon dioxide,” he said. “We’re still looking for it, actually,”

  1. O. Tschauner, S. Huang, E. Greenberg, V. B. Prakapenka, C. Ma, G. R. Rossman, A. H. Shen, D. Zhang, M. Newville, A. Lanzirotti, K. Tait. Ice-VII inclusions in diamonds: Evidence for aqueous fluid in Earth’s deep mantleScience, 2018; 359 (6380): 1136 DOI: 10.1126/science.aao3030
University of Nevada, Las Vegas. “Unique diamond impurities indicate water deep in Earth’s mantle: Scientific analysis of diamond impurities — known as inclusions — reveal naturally forming ice crystals and point to water-rich regions deep below the Earth’s crust.” ScienceDaily. ScienceDaily, 9 March 2018. <www.sciencedaily.com/releases/2018/03/180309170700.htm>

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WFS News: Half-Billion-Year-Old Fossil Brains Found in Ancient Predator (Kerygmachela kierkegaardi)

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

An artist's reconstruction of the 520-million-year-old Kerygmachela kierkegaardi depicts the ancient species as a formidable ocean predator. ILLUSTRATION BY REBECCA GELERNTER, NEARBIRD STUDIOS

An artist’s reconstruction of the 520-million-year-old Kerygmachela kierkegaardi depicts the ancient species as a formidable ocean predator. ILLUSTRATION BY REBECCA GELERNTER, NEARBIRD STUDIOS

With help from 15 fossils recently discovered in Greenland, scientists are now able to peer inside the brain of an animal that lived 520 million years ago.

The extinct species, Kerygmachela kierkegaardi, swam in ocean waters during an evolutionary arms race called the Cambrian explosion. Flanked by 11 wrinkly flaps on each side of its body, the ancient predator sported a long tail spine and a rounded head. Its fearsome forward-facing appendages grasped prey, says UK-based paleontologist Jakob Vinther, “making lives miserable for other animals.”

Previous fossil remains of the roughly one- to ten-inch creature came from loose rocks battered by weather. But the new finds are the species’ first to escape exposure to the elements, resulting in fossil nervous tissue that is providing new evolutionary insights into the brains of panarthropods—an animal group that includes water bears (tardigrades), velvet worms, and arthropods like crustaceans and insects.

The study, led by Vinther and the Korea Polar Research Institute‘s Tae-Yoon Park, was published March 9 in the journal Nature Communications.

Contradicting some previous accounts, the team argues that this new evidence appears to show that the common ancestor of all panarthropods did not have a complex three-part brain—and neither did the common ancestor of invertebrate panarthropods and vertebrates.

Modern arthropods begin developing with a single bundle of nerve cells above their gut. They bear two other brain segments, lying beside or beneath the gut, which migrate up during development to fuse with the first nerve bundle, forming an intricate, triple-segmented brain.

That structure can be traced back through the fossil record. Kerygmachela’s relatively simple brain, preserved as thin films of carbon, includes only the foremost of the three segments present in living arthropods.

The team believes that water bears, the eight-legged micro-critters known formally as tardigrades, have a simple one-segment brain similar to what they identify in KarygmachelaVelvet worms—soft-bodied, nocturnal ambush predators—also lack a three-part brain.

A HALF-BILLION-YEAR-OLD BRAINA well-preserved Kerygmachela fossil from Greenland (left) contains identifiable nervous system tissue in the head (closeup, right). This new evidence suggests that the common ancestor of all panarthropods lacked a complex brain. PHOTOGRAPH BY TAE YOON PARK, KOPRI

A HALF-BILLION-YEAR-OLD BRAINA well-preserved Kerygmachela fossil from Greenland  contains identifiable nervous system tissue in the head. This new evidence suggests that the common ancestor of all panarthropods lacked a complex brain.
PHOTOGRAPH BY TAE YOON PARK, KOPRI

So it makes sense to think that the common ancestor these animals share with arthropods also lacked a complex brain. Ditto for the organism that gave rise to both panarthropods and vertebrates, the other animal group whose brains have three segments.

Not all scientists are convinced of the details. Tardigrade brains may or may not develop based on segments at all, says Nicholas Strausfeld, a neuroscientist at the University of Arizona who was not involved in the study.

“If they’re going to say that the brain of Kerygmachela is like that of a tardigrade, you have to be really, really careful,” Strausfeld warns. “Because it might not be.” Tardigrades may lack a segmental brain altogether, instead relying on a ring of nerves around their mouths.

Vinther finds that perspective interesting. Whatever the case, he says, both ideas point to simpler ancestral nervous systems—and thus an evolutionary history in which animals’ brains evolved complex three-part structures multiple independent times.

The competition driving evolutionary arms races, Vinther says, “has led to similar outcomes that we see in different groups: eyes, complex brains, and so forth.”

Source: Article By Andrew Urevig,National Geographic

WFS News: Caudal autotomy as anti-predatory behaviour in Palaeozoic reptiles

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

Imagine that you’re a voracious carnivore who sinks its teeth into the tail of a small reptile and anticipates a delicious lunch, when, in a flash, the reptile is gone and you are left holding a wiggling tail between your jaws.

A new study by the University of Toronto Mississauga research team led by Professor Robert Reisz and PhD student Aaron LeBlanc, published March 5 in the open source journal, Scientific Reports, shows how a group of small reptiles who lived 289 million years ago could detach their tails to escape the grasp of their would-be predators — the oldest known example of such behaviour. The reptiles, called Captorhinus, weighed less than 2 kilograms and were smaller than the predators of the time. They were abundant in terrestrial communities during the Early Permian period and are distant relatives of all the reptiles today.

Fracture planes in captorhinid caudal vertebrae. (a) Artist’s reconstruction of the Permian reptile Captorhinus with an autotomous tail (inset showing anterior caudal vertebrae with fracture planes). (b) Image and (c) SEM image of an isolated anterior caudal vertebra (ROM 73769) with a fracture plane passing through the centrum (black arrow). (d) Ventral view of an anterior, rib-bearing caudal vertebra (ROM 77410) showing the absence of any fracture plane. (e) Ventral view of a caudal vertebra bearing a fracture plane (black arrows) (ROM 73771) (f) thin-section through the sagittal plane of a caudal vertebra (ROM 73773) with a fracture plane (black arrow) passing through the ventral portion of the centrum. (g) Close-up of fracture plane (black arrows) in (f) passing into the notochordal canal. Abbreviations: cb, cortical bone; cct, calcified cartilage; ce, centrum; nc, neural canal; ns, neural spine; ntc, notochordal canal. Reconstruction by Danielle Dufault. Anterior is to the left in all of the images.

Fracture planes in captorhinid caudal vertebrae. (a) Artist’s reconstruction of the Permian reptile Captorhinus with an autotomous tail (inset showing anterior caudal vertebrae with fracture planes). (b) Image and (c) SEM image of an isolated anterior caudal vertebra (ROM 73769) with a fracture plane passing through the centrum (black arrow). (d) Ventral view of an anterior, rib-bearing caudal vertebra (ROM 77410) showing the absence of any fracture plane. (e) Ventral view of a caudal vertebra bearing a fracture plane (black arrows) (ROM 73771) (f) thin-section through the sagittal plane of a caudal vertebra (ROM 73773) with a fracture plane (black arrow) passing through the ventral portion of the centrum. (g) Close-up of fracture plane (black arrows) in (f) passing into the notochordal canal. Abbreviations: cb, cortical bone; cct, calcified cartilage; ce, centrum; nc, neural canal; ns, neural spine; ntc, notochordal canal. Reconstruction by Danielle Dufault. Anterior is to the left in all of the images.

As small omnivores and herbivores, Captorhinus and its relatives had to scrounge for food while avoiding being preyed upon by large meat-eating amphibians and ancient relatives of mammals. “One of the ways captorhinids could do this,” says first author LeBlanc, “was by having breakable tail vertebrae.” Like many present-day lizard species, such as skinks, that can detach their tails to escape or distract a predator, the middle of many tail vertebrae had cracks in them.

Serial transverse sections through the centra of fracture plane-bearing caudal vertebrae in captorhinids. (a) Transverse section taken near the base of the centrum (ROM 73771); (b) Closeup of the fracture plane running across the ventral surface of the centrum in (a). (c) Transverse section taken at the level of the notochordal canal (ROM 73774). (d) Closeup of the fracture plane in c passing through the centrum into the notochordal canal. (e) Transverse section taken along the roof of the centrum (below the neural arch) (ROM 73774). (f) Closeup of fracture plane in (g) passing through the outer cortical bone, but not the more internal endosteal/endochondral bone. Abbreviations: cb, cortical bone; eb, endochondral bone; rl, reversal line; sf, Sharpey’s fibers. Anterior is to the left in all of the images.

Serial transverse sections through the centra of fracture plane-bearing caudal vertebrae in captorhinids. (a) Transverse section taken near the base of the centrum (ROM 73771); (b) Closeup of the fracture plane running across the ventral surface of the centrum in (a). (c) Transverse section taken at the level of the notochordal canal (ROM 73774). (d) Closeup of the fracture plane in c passing through the centrum into the notochordal canal. (e) Transverse section taken along the roof of the centrum (below the neural arch) (ROM 73774). (f) Closeup of fracture plane in (g) passing through the outer cortical bone, but not the more internal endosteal/endochondral bone. Abbreviations: cb, cortical bone; eb, endochondral bone; rl, reversal line; sf, Sharpey’s fibers. Anterior is to the left in all of the images.

It is likely that these cracks acted like the perforated lines between two paper towel sheets, allowing vertebrae to break in half along planes of weakness. “If a predator grabbed hold of one of these reptiles, the vertebra would break at the crack and the tail would drop off, allowing the captorhinid to escape relatively unharmed,” says Reisz, a Distinguished Professor of Biology at the University of Toronto Mississauga.

The authors note that being the only reptiles with such an escape strategy may have been a key to their success, because they were the most common reptiles of their time, and by the end of the Permian period 251 million years ago, captorhinids had dispersed across the ancient supercontinent of Pangaea. This trait disappeared from the fossil record when Captorhinus died out; it re-evolved in lizards only 70 million years ago.

Hypothesized path of autotomy break in the caudal centra of captorhinids. (a–c) Lateral, anterior, and ventral views of a fracture plane-bearing caudal centrum, showing the extend of the fracture plane, which does not pass through the neural arch or spine (ROM 73774). (d,e) SEM images of a post mortem break in a captorhinid caudal vertebra (ROM 77409) along its fracture plane. The break follows the plane of weakness formed by the autotomy plane (white arrow) and is found on the left (d) and right (e) sides, suggesting that this was the plane of weakness in life. (f) Reconstruction of caudal autotomy in a caudal vertebra. During autotomy, the fracture follows the path of least resistance through the dorsal half of the caudal centrum and the posterior base of the neural arch, bypassing the neural spine. Abbreviation: na, neural arch; nc, neural canal; ns, neural spine; ntc, notochordal canal. Anterior is to the left in all of the images.

Hypothesized path of autotomy break in the caudal centra of captorhinids. (a–c) Lateral, anterior, and ventral views of a fracture plane-bearing caudal centrum, showing the extend of the fracture plane, which does not pass through the neural arch or spine (ROM 73774). (d,e) SEM images of a post mortem break in a captorhinid caudal vertebra (ROM 77409) along its fracture plane. The break follows the plane of weakness formed by the autotomy plane (white arrow) and is found on the left (d) and right (e) sides, suggesting that this was the plane of weakness in life. (f) Reconstruction of caudal autotomy in a caudal vertebra. During autotomy, the fracture follows the path of least resistance through the dorsal half of the caudal centrum and the posterior base of the neural arch, bypassing the neural spine. Abbreviation: na, neural arch; nc, neural canal; ns, neural spine; ntc, notochordal canal. Anterior is to the left in all of the images.

They were able to examine more than 70 tail vertebrae — both juveniles and adults — and partial tail skeletons with splits that ran through their vertebrae. They compared these skeletons to those of other reptilian relatives of captorhinids, but it appears that this ability is restricted to this family of reptiles in the Permian period.

Using various paleontological and histological techniques, the authors discovered that the cracks were features that formed naturally as the vertebrae were developing. Interestingly, the research team found that young captorhinids had well-formed cracks, while those in some adults tended to fuse up. This makes sense, since predation is much greater on young individuals and they need this ability to defend themselves.

This study was possible thanks to the treasure trove of fossils available at the cave deposits near Richards Spur, Oklahoma.

  1. A. R. H. LeBlanc, M. J. MacDougall, Y. Haridy, D. Scott, R. R. Reisz. Caudal autotomy as anti-predatory behaviour in Palaeozoic reptilesScientific Reports, 2018; 8 (1) DOI: 10.1038/s41598-018-21526-3
University of Toronto. “Ancient reptile Captorhinus could detach its tail to escape predator’s grasp.” ScienceDaily. ScienceDaily, 6 March 2018. <www.sciencedaily.com/releases/2018/03/180306115741.htm>.

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