Prehistoric peopling in southeast Asia: Genomics of Jomon and other ancient skeletons

Uncovering the expansion processes of human habitats in the past is of great importance for understanding the origins and establishment of present-day populations and the acquisition of genetic characteristics of individuals as well as for investigating mechanisms of resistance against diseases and pathogens. Previous genetic/genomic studies aimed to uncover the expansion processes using present-day human genomes of different individuals and locations. However, it is not always possible to elucidate the expansion processes based on the genomic similarity of present-day populations due to the possibility of migrations of populations between regions in various periods. It is therefore impossible to uncover the precise expansion processes of populations in the past without knowledge of the genomic information existing in a designated region and period. Thus, expansion processes hypothesized so far were nothing but speculations based on assumptions about present-day genomes.

Model for migration routes into Southeast Asia uncovered by genomic data of prehistoric skeletons. Credit: Kanazawa University

Model for migration routes into Southeast Asia uncovered by genomic data of prehistoric skeletons.
Credit: Kanazawa University

Recent developments of DNA analysis technology have made it possible to obtain whole genome information from ultratrace amounts of DNA; we are now in an era where whole genome information can be obtained directly from ancient human skeletons discovered at archaeological sites. There remain, however, technical problems for obtaining whole genome information of ancient human skeletons. In particular, there are two main problems: first, genomic analyses*1) of poorly-preserved ancient remains in hot and humid regions of the world have up until now failed. Secondly, there is the risk of contamination of present-day human DNA in the DNA samples of ultratrace amounts from prehistoric remains. To evaluate objectively the possibility of such contamination, several different research groups must cross-check*2) one another in order to achieve exact genome sequencing; in other words, establishment of a collaborative research system is a prerequisite for attaining the highest level of scientific authenticity.

In order to cope with these problems, the present international research team, led by researchers from the University of Copenhagen with the participation of three researchers from Kanazawa University has established technologies to efficiently extract human DNA from skeletons discovered at prehistoric remains even under very poor conditions for DNA preservation. At the same time, an international system of research collaboration has been established for objectively evaluating the effects of contamination by present-day human DNA. Thanks to these efforts, the team has uncovered the expansion processes of human habitats and genetic interactions in hot and wet Southeast Asia, which was not possible previously with conventional technologies and research systems.

Worthy of special mention, the present study has been successful in determining the “whole genome” sequence of an individual with typical Jomon culture, while previous studies were only able to show a very limited “partial genome” sequence of two Jomon individuals. Thus, the present study is the first successful example to show the possibility of whole genome sequencing of prehistoric individuals in regions like Japan where preservation conditions are quite poor, possibly leading to further major progress in prehistoric genome studies.

In the present study, the international research team succeeded in extracting and sequencing DNA from 25 ancient individuals’ skeletons from Southeast Asian remains, where the condition of DNA preservation is very poor, and from one Japanese Jomon female skeleton. Upon comparison of the genomic data of ancient human skeletons with those of present-day human skeletons, it has become clear that those prehistoric populations in Southeast Asia can be classified into six groups.

Group 1 contains Hoabinhians from Pha Faen, Laos, hunter-gatherers (~8000 years ago), and prehistoric populations discovered from Gua Cha, Malaysia (~4000 years ago), being genetically close to present-day Önge and Jarawa from the Andaman Islands and Jehai from the Peninsular Malaysia. To our surprise, group 1 has higher genetic affinities with Ikawazu*3) Jomon individual (Tahara, Aichi), a female adult*4), than other present-day Southeast Asians. In addition, the Ikawazu Jomon genome*5) is best modelled contributing genetically present-day Japanese.

On the other hand, Groups 2-6 consist of ancient skeletons from the Neolithic Age, when farming started, until ~500 years ago. It is now found that they are genetically much different from Hoabinhians, each group having histories of migration and genetic interaction, i.e., inter-population mixture. Group 2 is found to be genetically close to the present-day Austroasiatic language-speaking groups such as Mlabri, but to have few genetic components common with the present-day East Asian populations. Group 3 is found to be genetically close to Kradai, Thailand, in the present-day Southeast Asian populations and to the Austronesian language-speaking groups. Group 4 is found to be genetically close to the present-day populations in South China. Group 5 is genetically close to the present-day populations in the western part of Indonesia. Group 6 is most closely related to present day Austronesian populations, with one individual showing slightly elevated Denisovan ancestry, an archaic hominin which is classified as a sister group of Neanderthals.

As above, Neolithic Southeast Asians are found to have been partially genetically influenced by ethnic groups in South China and to have had a genetic connection with populations in Taiwan; Neolithic Southeast Asians are found not to have been indigenous hunter-gatherers passively accepting farming but to have accepted farming gradually in the process of migrations of populations between the continent and islands. Conventional archaeology proposed the two-layer hypothesis that, in those periods, a large population with farming culture with rice and millet migrated into Southeast Asia and that they replaced the indigenous population. Additionally, the present study indicates that the genetic influence from South China with rice farming was only partial and that the migrating population did not replace the indigenous population completely. The present analysis shows that there were at least four big migration waves; migrations of Southeast Asians should be investigated with a new “complex model” framework.

The present study successfully elucidates for the first time the expansion/migration of prehistoric populations by genome analysis of skeletons discovered in Southeast Asia; conventionally, it was thought that such population expansion/migration could only be investigated using archaeological artifacts. An important outcome of the present study is that the same or analogous analyses could be applied to various regions to evaluate the history of population expansion/migration in much more detail and in a more scientific manner.

The genomic data obtained from ancient skeletons in Southeast Asia and from a Ikawazu Jomon individual provides an important basis for investigations on the origins of populations in wider East Asia. The whole genome information of a Jomon individual will be useful for direct comparison of genomic similarity with ancient East Asians of the corresponding period to Jomon in present-day Korea, China, Russia and others in the vicinity of the Japanese archipelago. More comparative studies are in progress on populations in wider areas. Note that the whole genome sequence obtained in this study for a Jomon individual corresponds to the Draft Genome Sequence in the Human Genome Project for the present-day humans. We aim at Complete Genome Sequence with higher accuracy.

This study is an interdisciplinary undertaking combining anthropology and archaeology in a close collaboration, allowing us to establish ourselves at the starting point for research on the origin of Jomon and its diversity. By more genome analyses of more Jomon skeletons from different Jomon sites, genetic diversity of Jomon populations will be explored over the Japanese archipelago. It is expected through such studies that various interactions among Jomon groups should be revealed together with migrations of archaeological artifacts such as potteries and stone tools as well as migrations of populations. Based on the outcome of the present study, novel anthropological and archaeological approaches would be further developed.

Source: www.sciencedaily.com

Citation: Kanazawa University. “Prehistoric peopling in southeast Asia: Genomics of Jomon and other ancient skeletons.” ScienceDaily. ScienceDaily, 9 August 2018. <www.sciencedaily.com/releases/2018/08/180809093427.htm>.

WFS News: Nano-Scale Spheroids and Fossils from the Ediacaran Doushantuo Formation in China

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

Exceptionally preserved nano-scale spheroids derived from microbial processes and nano-scale fossils have been discovered from the black shales of the Jijiawan section of the Ediacaran Doushantuo Formation in the Yangtze Gorge area of Hubei Province, southern China. The numerous soccer ball-like spheroids are pyritized. Their morphology and abundant preservation may suggest that they could possibly be related to larger spheroids, regardless of the tremendous dimensional gap found in the phosphorite and cherts of the Doushantuo Formation, including those recognized as ‘embryos’. The colony-like spheroids preserved in situ and obtained by acid maceration are compared with known Neoproterozoic microfossils—Bavlinella faveolata (or Sphaerocongregus variabilis). Additionally, nano-scale fossil bodies, characterized by morphological features comparable to living cyanobacteria, fungi and possible unicellular heterotrophic protists were observed in different minor laminae of the black shale samples. This study aims to reveal the aspects of nano-scale biota preserved in the black shale of the Ediacaran Doushantuo Formation, and highlight the taphonomy of microorganisms during the key transition from the anoxic deeper oceans to the oxygenated oceans of the early Ediacaran interval.

Nano-scale spheroids found in the black shales of the Ediacaran Doushantuo Formation in the Jijiawan section, Hubei, China.A–E, I, L, M Soccer ball-like spheroids with probable hollow interior and polygonal cracks, preserved in situ (except specimen M, which was obtained by acid maceration); specimen I displays tuberculiform ornamentation on its surface. F, G colony-like spheroids, which were obtained from organic residues of acid maceration and are compared with known fossils — Bavlinella faveolata. G is a magnification of part of F to show ductile walls (arrow) and possible fine ornamentation on the surface. H, J, K single spheroids with hollow cavities, H was obtained from organic residues of acid maceration, J and K are preserved in situ.

Nano-scale spheroids found in the black shales of the Ediacaran Doushantuo Formation in the Jijiawan section, Hubei, China.A–E, I, L, M Soccer ball-like spheroids with probable hollow interior and polygonal cracks, preserved in situ (except specimen M, which was obtained by acid maceration); specimen I displays tuberculiform ornamentation on its surface. F, G colony-like spheroids, which were obtained from organic residues of acid maceration and are compared with known fossils — Bavlinella faveolata. G is a magnification of part of F to show ductile walls (arrow) and possible fine ornamentation on the surface. H, J, K single spheroids with hollow cavities, H was obtained from organic residues of acid maceration, J and K are preserved in situ.

Morphological features similar to those of modern cyanobacteria characterize the preservation of nano-scale fossils [45]. Possible fungal spore and unicellular heterotrophic protists may imply that a diverse nano-scale biota, including prokaryotes and heterotrophic eukaryotes, existed in the early Ediacaran anoxic deeper ocean. Although most of the nano-scale spheroids and fossils obtained from the black shale of the lower part of the Doushantuo Formation were strongly carbonized and mineralized, these findings further reveal aspects of life during this key period of transition from anoxic deeper oceans to oxygenated oceans.

Consequently, the investigation of the biological link that may have existed between such nano-scale microbes and much larger microfossils, particularly acanthmorphic acritarchs, animal embryos and other possible animal remains, during the earlier Ediacaran period is significant. Mineralogically, the studied black shales contain abundant pyrite and gypsum, which alternate within thin laminae. This may signify that redox conditions were fluctuating and a semi-enclosed marine lagoonal palaeoenvironment could have been suitable for the sedimentation and diagenesis of the studied Doushantuo black shales. The fact that many specimens of colony-like spheroids are comparable in their nano-scale biotic associations to Bavlinellafaveolata and other cyanobacteria may suggest that an extraordinarily stressed environment existed during this key geological interval.

Tenger Borjigin1Leiming Yin2*Lizeng Bian3Xunlai Yuan2Chuanming Zhou2Fanwei Meng2Xiaomin Xie1Fang Bao1
1 Key Laboratory of Petroleum Accumulation Mechanisms, Wuxi Research Institute of Petroleum Geology, SINOPEC, Wuxi 214151, Jiangsu, China
2 State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences, Nanjing 210008, Jiangsu, China
3 School of Earth Sciences and Engineering, Nanjing University, Nanjing 210008, Jiangsu, China

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

Scientists solve the mystery behind the origin of skeletons!!!

Scientists at The University of Manchester and the University of Bristol have used powerful X-rays to peer inside the skeletons of some of our oldest vertebrate relatives, solving a 160-year-old mystery about the origin of our skeletons.

Living vertebrates have skeletons built from four different tissue types: bone and cartilage (the main tissues that human skeletons are made from), and dentine and enamel (the tissues from which our teeth are constructed). These tissues are unique because they become mineralised as they develop, giving the skeleton strength and rigidity.

Evidence for the early evolution of our skeletons can be found in a group of fossil fishes called heterostracans, which lived over 400 million years ago. These fishes include some of the oldest vertebrates with a mineralised skeleton that have ever been discovered. Exactly what tissue heterostracan skeletons were made from has long puzzled scientists.

Now a team of researchers from the University of Manchester, the University of Bristol and the Paul Scherrer Institute in Switzerland have taken a detailed look inside heterostracan skeletons using Synchrotron Tomography: a special type of CT scanning using very high energy X-rays produced by a particle accelerator. Using this technique, the team have identified this mystery tissue.

Lead researcher Dr Joseph Keating, from Manchester’s School of Earth of Environmental Scientists, explained: “Heterostracan skeletons are made of a really strange tissue called ‘aspidin’. It is crisscrossed by tiny tubes and does not closely resemble any of the tissues found in vertebrates today. For a 160 years, scientists have wondered if aspidin is a transitional stage in the evolution of mineralised tissues.”

A fossil heterostracan, Errivaspis waynensis, from the early Devonian (approximately 419 million years ago) of Herefordshire, UK. Credit: Image from Keating et al. 2018

A fossil heterostracan, Errivaspis waynensis, from the early Devonian (approximately 419 million years ago) of Herefordshire, UK.
Credit: Image from Keating et al. 2018

The results of this study, published in Nature Ecology and Evolution, show that the tiny tubes are voids that originally housed fibre-bundles of collagen, a type of protein found in your skin and bones.

These findings enabled Dr Keating to rule out all but one hypothesis for the tissue’s identity: aspidin is the earliest evidence of bone in the fossil record.

Co-author, Professor Phil Donoghue from the University of Bristol concludes: “These findings change our view on the evolution of the skeleton. Aspidin was once thought to be the precursor of vertebrate mineralised tissues. We show that it is, in fact, a type of bone, and that all these tissues must have evolved millions of years earlier.”

Citation: University of Manchester. “160-year-old mystery about the origin of skeletons solved.” ScienceDaily. ScienceDaily, 31 July 2018. <www.sciencedaily.com/releases/2018/07/180731104259.htm>.

Source: www.sciencedaily.com

Sound waves reveal enormous diamond cache deep in Earth’s interior

There may be more than a quadrillion tons of diamond hidden in the Earth’s interior, according to a new study from MIT and other universities. But the new results are unlikely to set off a diamond rush. The scientists estimate the precious minerals are buried more than 100 miles below the surface, far deeper than any drilling expedition has ever reached.

The ultradeep cache may be scattered within cratonic roots — the oldest and most immovable sections of rock that lie beneath the center of most continental tectonic plates. Shaped like inverted mountains, cratons can stretch as deep as 200 miles through the Earth’s crust and into its mantle; geologists refer to their deepest sections as “roots.”

In the new study, scientists estimate that cratonic roots may contain 1 to 2 percent diamond. Considering the total volume of cratonic roots in the Earth, the team figures that about a quadrillion (1016) tons of diamond are scattered within these ancient rocks, 90 to 150 miles below the surface.

There may be more than a quadrillion tons of diamond hidden in the Earth's interior. Credit: © KristijanZontar / Fotolia

There may be more than a quadrillion tons of diamond hidden in the Earth’s interior.
Credit: © KristijanZontar / Fotolia

“This shows that diamond is not perhaps this exotic mineral, but on the [geological] scale of things, it’s relatively common,” says Ulrich Faul, a research scientist in MIT’s Department of Earth, Atmospheric, and Planetary Sciences. “We can’t get at them, but still, there is much more diamond there than we have ever thought before.”

Faul’s co-authors include scientists from the University of California at Santa Barbara, the Institut de Physique du Globe de Paris, the University of California at Berkeley, Ecole Polytechnique, the Carnegie Institution of Washington, Harvard University, the University of Science and Technology of China, the University of Bayreuth, the University of Melbourne, and University College London.

A sound glitch

Faul and his colleagues came to their conclusion after puzzling over an anomaly in seismic data. For the past few decades, agencies such as the United States Geological Survey have kept global records of seismic activity — essentially, sound waves traveling through the Earth that are triggered by earthquakes, tsunamis, explosions, and other ground-shaking sources. Seismic receivers around the world pick up sound waves from such sources, at various speeds and intensities, which seismologists can use to determine where, for example, an earthquake originated.

Scientists can also use this seismic data to construct an image of what the Earth’s interior might look like. Sound waves move at various speeds through the Earth, depending on the temperature, density, and composition of the rocks through which they travel. Scientists have used this relationship between seismic velocity and rock composition to estimate the types of rocks that make up the Earth’s crust and parts of the upper mantle, also known as the lithosphere.

However, in using seismic data to map the Earth’s interior, scientists have been unable to explain a curious anomaly: Sound waves tend to speed up significantly when passing through the roots of ancient cratons. Cratons are known to be colder and less dense than the surrounding mantle, which would in turn yield slightly faster sound waves, but not quite as fast as what has been measured.

“The velocities that are measured are faster than what we think we can reproduce with reasonable assumptions about what is there,” Faul says. “Then we have to say, ‘There is a problem.’ That’s how this project started.”

Diamonds in the deep

The team aimed to identify the composition of cratonic roots that might explain the spikes in seismic speeds. To do this, seismologists on the team first used seismic data from the USGS and other sources to generate a three-dimensional model of the velocities of seismic waves traveling through the Earth’s major cratons.

Next, Faul and others, who in the past have measured sound speeds through many different types of minerals in the laboratory, used this knowledge to assemble virtual rocks, made from various combinations of minerals. Then the team calculated how fast sound waves would travel through each virtual rock, and found only one type of rock that produced the same velocities as what the seismologists measured: one that contains 1 to 2 percent diamond, in addition to peridotite (the predominant rock type of the Earth’s upper mantle) and minor amounts of eclogite (representing subducted oceanic crust). This scenario represents at least 1,000 times more diamond than people had previously expected.

“Diamond in many ways is special,” Faul says. “One of its special properties is, the sound velocity in diamond is more than twice as fast as in the dominant mineral in upper mantle rocks, olivine.”

The researchers found that a rock composition of 1 to 2 percent diamond would be just enough to produce the higher sound velocities that the seismologists measured. This small fraction of diamond would also not change the overall density of a craton, which is naturally less dense than the surrounding mantle.

“They are like pieces of wood, floating on water,” Faul says. “Cratons are a tiny bit less dense than their surroundings, so they don’t get subducted back into the Earth but stay floating on the surface. This is how they preserve the oldest rocks. So we found that you just need 1 to 2 percent diamond for cratons to be stable and not sink.”

In a way, Faul says cratonic roots made partly of diamond makes sense. Diamonds are forged in the high-pressure, high-temperature environment of the deep Earth and only make it close to the surface through volcanic eruptions that occur every few tens of millions of years. These eruptions carve out geologic “pipes” made of a type of rock called kimberlite (named after the town of Kimberley, South Africa, where the first diamonds in this type of rock were found). Diamond, along with magma from deep in the Earth, can spew out through kimberlite pipes, onto the surface of the Earth.

For the most part, kimberlite pipes have been found at the edges of cratonic roots, such as in certain parts of Canada, Siberia, Australia, and South Africa. It would make sense, then, that cratonic roots should contain some diamond in their makeup.

“It’s circumstantial evidence, but we’ve pieced it all together,” Faul says. “We went through all the different possibilities, from every angle, and this is the only one that’s left as a reasonable explanation.”

This research was supported, in part, by the National Science Foundation.

Citation: Massachusetts Institute of Technology. “Sound waves reveal enormous diamond cache deep in Earth’s interior: Study finds one to two percent of Earth’s oldest mantle rocks are made from diamond.” ScienceDaily. ScienceDaily, 16 July 2018. <www.sciencedaily.com/releases/2018/07/180716114538.htm>.

Source: www.sciencedaily.com

Glaciers in East Antarctica also ‘imperiled’ by climate change

Source:University of California – Irvine

A team of scientists from the University of California, Irvine has found evidence of significant mass loss in East Antarctica’s Totten and Moscow University glaciers, which, if they fully collapsed, could add 5 meters (16.4 feet) to the global sea level.

In a paper published this week in the American Geophysical Union journal Geophysical Research Letters, the glaciologists estimate that between April 2002 and September 2016, the two glaciers lost about 18.5 billion tons of ice per year — equivalent to 0.7 millimeters (0.03 inches) of global sea level rise over the analyzed time period.

UCI’s researchers discovered this by applying a locally optimized technique to data from NASA’s Gravity Recovery & Climate Experiment satellite mission, combined with mass balance approximations from regional atmospheric climate models and ice discharge measurements by NASA’s Operation IceBridge and Measures projects.

“For this research, we used an improved methodology with GRACE data to retrieve the mass loss in an area undergoing rapid change,” said lead author Yara Mohajerani, a graduate student in UCI’s Department of Earth System Science. “By overlaying these data with independent measurements, we improve our confidence in the results and the conclusion that Totten and Moscow University are imperiled.”

Making up roughly two-thirds of the Antarctic continent, East Antarctica has been viewed by polar researchers as less threatened by climate change than the volatile ice sheets in West Antarctica and the Antarctic Peninsula.

“Both of these glaciers are vulnerable to the intrusion of warm ocean water and hold considerable potential for sea level rise,” said co-author Eric Rignot, Donald Bren Professor and chair of Earth system science at UCI. “This work highlights that East Antarctic glaciers are as important to our future as those in the continent’s western regions.”

According to co-author Isabella Velicogna, professor of Earth system science, it’s challenging to study the Totten and Moscow University glaciers because the signal of change is much weaker than that of their counterparts in the west.

“In this remote part of the world, the data from GRACE and other satellite missions are critical for us to understand the glacier evolution,” she said.

Citation: University of California – Irvine. “Glaciers in East Antarctica also ‘imperiled’ by climate change: Usually seen as less vulnerable, they carry the potential to add 16 feet to global sea level.” ScienceDaily. ScienceDaily, 26 July 2018. <www.sciencedaily.com/releases/2018/07/180726161009.htm>.

Yellowstone super-volcano has a different history than previously thought

The long-dormant Yellowstone super-volcano in the American West has a different history than previously thought, according to a new study by a Virginia Tech geoscientist.

Scientists have long thought that Yellowstone Caldera, part of the Rocky Mountains and located mostly in Wyoming, is powered by heat from the Earth’s core, similar to most volcanoes such as the recently active Kilauea volcano in Hawaii. However, new research published in Nature Geoscience by Ying Zhou, an associate professor with the Virginia Tech College of Science’s Department of Geosciences, shows a different past.

“In this research, there was no evidence of heat coming directly up from the Earth’s core to power the surface volcano at Yellowstone,” Zhou said. “Instead, the underground images we captured suggest that Yellowstone volcanoes were produced by a gigantic ancient oceanic plate that dove under the Western United States about 30 million years ago. This ancient oceanic plate broke into pieces, resulting in perturbations of unusual rocks in the mantle which led to volcanic eruptions in the past 16 million years.”

This is the location of the Yellowstone's hotspot track. The triangles indicate general locations of the Yellowstone and Snake River Plain age-progressive volcanoes with ages shown in millions of years, plotted on a topography map of the Western United States. Credit: Virginia Tech

This is the location of the Yellowstone’s hotspot track. The triangles indicate general locations of the Yellowstone and Snake River Plain age-progressive volcanoes with ages shown in millions of years, plotted on a topography map of the Western United States.
Credit: Virginia Tech

The eruptions were very explosive, Zhou added. A theoretical seismologist, Zhou created X-ray-like images of the Earth’s deep interior from USArray — part of the Earthscope project funded by the National Science Foundation — and discovered an anomalous underground structure at a depth of about 250 to 400 miles right beneath the line of volcanoes.

“This evidence was in direct contradiction to the plume model,” Zhou said.

In her study, Zhou found the new images of the Earth’s deep interior showed that the oceanic Farallon plate, which used to be where the Pacific Ocean is now, wedged itself beneath the present-day Western United States. The ancient oceanic plate was broken into pieces just like the seafloor in the Pacific today. A section of the subducted oceanic plate started tearing off and sinking down to the deep earth.

The sinking section of oceanic plate slowly pushed hot materials upward to form the volcanoes that now make up Yellowstone. Further, the series of volcanoes that make up Yellowstone have been slowly moving, achingly so, ever since. “The process started at the Oregon-Idaho border about 16 million years ago and propagated northwestward, forming a line of volcanoes that are progressively younger as they stretched northwest to present-day Wyoming,” Zhou added.

The previously-held plume model was used to explain the unique Yellowstone hotspot track — the line of volcanoes in Oregon, Idaho, and Wyoming that dots part of the Midwest. “If the North American plate was moving slowly over a position-fixed plume at Yellowstone, it will displace older volcanoes towards the Oregon-Idaho border and form a line of volcanoes, but such a deep plume has not been found.” Zhou said. So, what caused the track? Zhou intends to find out.

“It has always been a problem there, and scientists have tried to come up with different ways to explain the cause of Yellowstone volcanoes, but it has been unsuccessful,” she said, adding that hotspot tracks are more popular in oceans, such as the Hawaii islands. The frequent Geyser eruptions at Yellowstone are of course not volcanic eruptions with magna, but due to super-heated water. The last Yellowstone super eruption was about 630,000 years ago, according to experts. Zhou has no predictions on when or if Yellowstone could erupt again.

The use of the X-ray-like images for this study is unique in itself. Just as humans can see objects in a room when a light is on, Zhou said seismometers can see structures deep within the earth when an earthquake occurs. The vibrations spread out and create waves when they hit rocks. The waves are detected by seismometers and used in what is known as diffraction tomography.

“This is the first time the new imaging theory has been applied to this type of seismic data, which allowed us to see anomalous structures in the Earth’s mantle that would otherwise not be resolvable using traditional methods,” Zhou said.

Zhou will continue her study of Yellowstone. “The next step will be to increase the resolution of the X-ray-like images of the underground rock,” she added.

“More detailed images of the unusual rocks in the deep earth will allow us to use computer simulation to recreate the fragmentation of the gigantic oceanic plate and test different scenarios of how rock melting and magma feeding system work for the Yellowstone volcanoes.”

Citation: Virginia Tech. “Yellowstone super-volcano has a different history than previously thought: Yellowstone super-volcano eruptions were produced by gigantic ancient oceanic plate.” ScienceDaily. ScienceDaily, 26 July 2018. <www.sciencedaily.com/releases/2018/07/180726085827.htm>.

Source: www.sciencedaily.com

Paleontologists discover largest dinosaur foot ever

The Black Hills region of the United States is famous today for tourist attractions like Deadwood and Mount Rushmore, but around 150 million years ago it was home to one of the largest dinosaurs known. This dinosaur was a member of the sauropod family with long necks and tails. These giant plant-eating dinosaurs like Brontosaurus and Diplodocus were the largest land animals that ever lived on this planet.

The foot described in a new scientific paper recently published in the open-access journal PeerJ — the Journal of Life and Environmental Sciences was excavated in 1998 by an expedition from the University of Kansas, with Anthony Maltese, lead author of the study, as member of the crew. As he writes, it was immediately apparent that the foot, nearly a meter wide, was from an extremely large animal — so the specimen was nicknamed “Bigfoot.”

Photograph from the excavations in 1998, with the brachiosaur foot bones below a tail of a Camarasaurus. University of Kansas expedition crew member as a scale. Credit: Photo courtesy of the KUVP archives

Photograph from the excavations in 1998, with the brachiosaur foot bones below a tail of a Camarasaurus. University of Kansas expedition crew member as a scale.
Credit: Photo courtesy of the KUVP archives

Now, after detailed preparation and study, Maltese and his international team of researchers from the USA, Switzerland, and Germany identified it as belonging to an animal very closely related to Brachiosaurus, famous for its appearance in the 1993 film Jurassic Park.

Anthony Maltese, Emanuel Tschopp, Femke Holwerda, and David Burnham used 3D scanning and detailed measurements to compare Bigfoot to sauropod feet from numerous species. Their research confirmed that this foot was unusually large. According to Holwerda, a Dutch PhD student at the Ludwig Maximilians University of Munich, Germany, comparisons with other sauropod feet showed that Bigfoot was clearly the largest dinosaur foot discovered to date.

It also confirmed that brachiosaurs inhabited a huge area from eastern Utah to northwestern Wyoming, 150 million years ago. “This is surprising,” says Tschopp, a Swiss paleontologist working at the American Museum of Natural History in New York, “many other sauropod dinosaurs seem to have inhabited smaller areas during that time.”

According to Maltese, who was part of the original University of Kansas team in 1998 but is now at the Rocky Mountain Dinosaur Resource Center in Woodland Park, Colorado, the rock outcrops that produced this fossil hold many more “fantastic dinosaur skeletons,” and the research team hopes to continue their studies on fossils from there.

Citation: PeerJ. “Paleontologists discover largest dinosaur foot ever.” ScienceDaily. ScienceDaily, 24 July 2018. <www.sciencedaily.com/releases/2018/07/180724110119.htm>.

Source: www.sciencedaily.com

The Earth’s youngest banded iron formation discovered.

Source:University of Alberta

The banded iron formation, located in western China, has been conclusively dated as Cambrian in age. Approximately 527 million years old, this formation is young by comparison to the majority of discoveries to date. The deposition of banded iron formations, which began approximately 3.8 billion years ago, had long been thought to terminate before the beginning of the Cambrian Period at 540 million years ago.

Earth's youngest banded iron formation in western China. Credit: Zhiquan Li

Earth’s youngest banded iron formation in western China.
Credit: Zhiquan Li

“This is critical, as it is the first observation of a Precambrian-like banded iron formation that is Early Cambrian in age. This offers the most conclusive evidence for the presence of widespread iron-rich conditions at a time, confirming what has recently been suggested from geochemical proxies,” said Kurt Konhauser, professor in the Department of Earth and Atmospheric Sciences and co-author. Konhauser supervised the research that was led by Zhiquan Li, a PhD candidate from Beijing while on exchange at UAlberta.

The Early Cambrian is known for the rise of animals, so the level of oxygen in seawater should have been closer to near modern levels. “This is important as the availability of oxygen has long been thought to be a handbrake on the evolution of complex life, and one that should have been alleviated by the Early Cambrian,” says Leslie Robbins, a PhD candidate in Konhauser’s lab and a co-author on the paper.

The researchers compared the geological characteristics and geochemistry to ancient and modern samples to find an analogue for their deposition. The team relied on the use of rare earth element patterns to demonstrate that the deposit formed in, or near, a chemocline in a stratified iron-rich basin.

“Future studies will aim to quantify the full extent of these Cambrian banded iron formations in China and whether similar deposits can be found elsewhere,” says Kurt Konhauser.

Citation: University of Alberta. “Scientists discover Earth’s youngest banded iron formation in western China: Discovery provides evidence of iron-rich seawater much later than previously thought.” ScienceDaily. ScienceDaily, 11 July 2018. <www.sciencedaily.com/releases/2018/07/180711182731.htm>.

Earth’s ancient biosphere deciphered using prehistoric lake deposits.

Source:McGill University

A sample of ancient oxygen, teased out of a 1.4 billion-year-old evaporative lake deposit in Ontario, provides fresh evidence of what the Earth’s atmosphere and biosphere were like during the interval leading up to the emergence of animal life.

The findings, published in the journal Nature, represent the oldest measurement of atmospheric oxygen isotopes by nearly a billion years. The results support previous research suggesting that oxygen levels in the air during this time in Earth history were a tiny fraction of what they are today due to a much less productive biosphere.

“It has been suggested for many decades now that the composition of the atmosphere has significantly varied through time,” says Peter Crockford, who led the study as a PhD student at McGill University. “We provide unambiguous evidence that it was indeed much different 1.4 billion years ago.”

The study provides the oldest gauge yet of what earth scientists refer to as “primary production,” in which micro-organisms at the base of the food chain — algae, cyanobacteria, and the like — produce organic matter from carbon dioxide and pour oxygen into the air.

A smaller biosphere

“This study shows that primary production 1.4 billion years ago was much less than today,” says senior co-author Boswell Wing, who helped supervise Crockford’s work at McGill. “This means that the size of the global biosphere had to be smaller, and likely just didn’t yield enough food — organic carbon — to support a lot of complex macroscopic life,” says Wing, now an associate professor of geological sciences at University of Colorado at Boulder.

To come up with these findings, Crockford teamed up with colleagues from Yale University, University of California Riverside, and Lakehead University in Thunder Bay, Ontario, who had collected pristine samples of ancient salts, known as sulfates, found in a sedimentary rock formation north of Lake Superior. Crockford shuttled the samples to Louisiana State University, where he worked closely with co-authors Huiming Bao, Justin Hayles, and Yongbo Peng, whose lab is one of a handful in the world using a specialized mass-spectrometry technique capable of probing such materials for rare oxygen isotopes within sulfates.

The work also sheds new light on a stretch of Earth’s history known as the “boring billion” because it yielded little apparent biological or environmental change.

“Subdued primary productivity during the mid-Proterozoic era — roughly 2 billion to 800 million years ago — has long been implied, but no hard data had been generated to lend strong support to this idea,” notes Galen Halverson, a co-author of the study and associate professor of earth and planetary sciences at McGill. “That left open the possibility that there was another explanation for why the middle Proterozoic ocean was so uninteresting, in terms of the production and deposit of organic carbon.” Crockford’s data “provide the direct evidence that this boring carbon cycle was due to low primary productivity.”

Exoplanet clues

The findings could also help inform astronomers’ search for life outside our own solar system.

“For most of Earth history our planet was populated with microbes, and projecting into the future they will likely be the stewards of the planet long after we are gone,” says Crockford, now a postdoctoral researcher at Princeton University and Israel’s Weizmann Institute of Science. “Understanding the environments they shape not only informs us of our own past and how we got here, but also provides clues to what we might find if we discover an inhabited exoplanet.”

Credit: Sciencedaily.com

Curious armoured dinosaur fossil discovered in Utah!!!!

Source:University of Utah

Fossils of a new genus and species of an ankylosaurid dinosaur — Akainacephalus johnsoni — have been unearthed in the Kaiparowits Formation of Grand Staircase-Escalante National Monument (GSENM), in Kane County, southern Utah, U.S.A., and are revealing new details about the diversity and evolution of this group of armored dinosaurs. Expected to look like other North American Late Cretaceous ankylosaurid dinosaurs with smooth bony armor on the skull, the new research suggests just the opposite and indicates that the defining features of Akainacephalus, specifically the spiky bony armor covering the skull and snout, align more closely with Asian ankylosaurids, who also have more pronounced spikes covering their skulls.

Akainacephalus was announced today in the open-access scientific journal PeerJ and unveiled on exhibit in the Past Worlds Gallery of the Natural History Museum of Utah at the Rio Tinto Center in Salt Lake City, Utah. The genus name is derived from the Greek words akaina, which means ‘thorn’ or ‘spike’, and cephalus, meaning ‘head.’ The species epithet johnsoni honors Randy Johnson, a dedicated museum volunteer who skillfully prepared its skull. Other talented volunteers helped to prepare the rest of the specimen.

“I’m a retired chemist, but I’ve always been interested in most of the science disciplines. I never thought that I would have the opportunity to actually work on fossils that could be important for paleontologists,” said Randy Johnson. “Now that I’m a museum volunteer, I’m getting the opportunity to work on a large variety of fossils and consult with top paleontologists — it’s like a dream second career. I couldn’t believe it when they told me they are naming the ankylosaur after me, a once in a lifetime honor,” said Johnson.

Ankylosaurids are a group of four-legged herbivorous armored dinosaurs with imposing bony tail clubs. Though ankylosaurids originated in Asia between 125 — 100 million years ago, they do not appear in the western North American fossil record until ~77 million years ago. The new species Akainacephalus lived 76 million years ago during the Late Cretaceous Period and offers the most complete skeleton of an ankylosaurid dinosaur found in the southwestern US. It includes a complete skull, much of the vertebral column, including a complete tail club, several fore and hind limbs elements, and bony body armor that includes two neck rings and spiked armor plates.

The unique arrangement of bony armor in the shape of small cones and pyramids covering the snout and head is the key research finding indicating that Akainacephalus is closely related to the New Mexican ankylosaurid Nodocephalosaurus kirtlandensis. Surprisingly, Akainacephalus and Nodocephalosaurus are more closely related to Asian ankylosaurids such as Saichania and Tarchia than to other Late Cretaceous North American ankylosaurids, including Ankylosaurusand Euoplocephalus. Both of the latter taxa possess flat skull armor.

“A reasonable hypothesis would be that ankylosaurids from Utah are related to those found elsewhere in western North America, so we were really surprised to discover that Akainacephalus was so closely related to species from Asia,” remarked Randall Irmis, co-author of the study.

Though ankylosaurids originated in Asia between 125 — 100 million years ago, they do not appear in the North American fossil record until around 77 million years ago. Akainacephalus once roamed the southern part of Laramidia, a landmass on the western coast of a shallow sea that flooded the central region, splitting the continent of North America in two. This caused isolation along western and eastern portions of the North American continent during the Late Cretaceous Period, between 95-70 million years ago.

Lead author Jelle Wiersma suggests that the geographic distribution of Late Cretaceous ankylosaurids throughout the Western Interior was the result of several geologically brief intervals of lowered sea level that allowed Asian ankylosaurid dinosaurs to immigrate to North America several times during the Late Cretaceous, resulting in the presence of two separate groups of ankylosaurid dinosaurs. This lowering of sea levels exposed the Beringian land bridge, allowing dinosaurs and other animals to move between Asia and North America.

“It is always exciting to name a new fossil taxon, but it is equally exciting if that taxon also provides additional insights into the bigger picture of its life, such as its diet or aspects of its behavior, and the environment it lived in,” said Wiersma. “Such is exactly the case with Akainacephalus johnsoni; not only is this the first described and named Late Cretaceous ankylosaurid dinosaur from Utah, but this unique animal also strengthens the evidence that distinct northern and southern provincialism existed during the late Campanian stage in Laramidia, because to date, we don’t see this type of ankylosaurid dinosaurs in the fossil record of northern Laramidia,” he said.

Wiersma explained that additionally, together with its close relative Nodocephalosaurus from New Mexico, Akainacephalus looks very different compared to other North American ankylosaurids such as Ankylosaurus, but instead, look much more like Asian ankylosaurids including Saichania and Tarchia. From these observations we can conclude that at least two immigration events took place during Late Cretaceous times when lowered sea levels exposed the Beringian land bridge, connecting Asia with western North America.

Ankylosaurid dinosaurs, among many other groups of animals, eventually crossed this land bridge, emigrating from Asia into western North America, resulting into two different types of Late Cretaceous ankylosaurid dinosaurs: ones that evolved flatter skull armor like Ankylosaurus and Euoplocephalus, and ones possessing very spiky skull armor such as Akainacephalus and Nodocephalosaurus.

“It is extremely fascinating and important for the science of paleontology that we can read so much information from the fossil record, allowing us to better understand extinct organisms and the ecosystems they were a part of,” concluded Wiersma.

These new findings are part of a study funded in large part by the Bureau of Land Management, as well as the Geological Society of America, and a University of Utah Department of Geology & Geophysics Graduate Student Grant. The project was led by University of Utah M.Sc. student Jelle Wiersma, now a Ph.D. student in the Dept. of Geosciences at James Cook University, Queensland, Australia. Wiersma was advised by co-author Dr. Randall Irmis, chief curator and curator of paleontology at the Natural History Museum of Utah, and associate professor in the Dept. of Geology and Geophysics, University of Utah.

Anklysaurid Dinosaurs on the Lost Continent of Southern Laramidia

Akainacephalus johnsoni was discovered in Grand Staircase-Escalante National Monument (GSENM) which encompasses a large area of high desert terrain in south-central Utah. This vast and rugged region, part of the National Landscape Conservation System administered by the Bureau of Land Management (BLM), was the last major area in the lower 48 states to be formally mapped by cartographers.

During the Late Cretaceous, GSENM was in the southern portion of Laramidia, which stretched from the Arctic Circle to the Gulf of Mexico. Akainacephalus is part of a growing number of new dinosaur discoveries over the past 15 years demonstrating the incredible diversity of animals and plants living on Laramidia between 80-75 million years ago. One of the most exciting conclusions from this work is that nearly every species of dinosaur discovered in GSENM is new to science, and Akainacephalus is no exception. Other recently discovered species include large and small meat-eating dinosaurs (e.g., tyrannosaurs), horned dinosaurs, and duck-billed dinosaurs. “A major long-term goal of our work in southern Utah is to try and understand why the species in GSENM differ from relatives of the same geologic age found in other parts of Laramidia,” said Wiersma. Hypotheses for the differences include changes in sea level, climate differences across latitude, and physical barriers to animal movement such as mountains and large rivers.

Fact Sheet: Major Points of the Paper

(1) Akainacephalus is a remarkable new species of ankylosaurid dinosaur from the upper Campanian Kaiparowits Formation in Grand Staircase-Escalante National Monument in Kane County, southern Utah.

(2) Akainacephalus is the most complete Late Cretaceous ankylosaurid dinosaur discovered from Utah and the southwestern U.S., and is distinguished by a number of unique features, including spikes and cones of the bony exterior covering the head and snout.

(3) The spikes and cones of bony armor on the skull of Akainacephalus are similar to those found on the New Mexican ankylosaurid Nodocephelausaurus kirtlandensis but distinct from all other known Late Cretaceous Laramidian ankylosaurids such as AnkylosaurusEuoplocephalus, and Ziapelta, indicating these two species are more closely related to some Asian ankylosaurids.

(4) The new ankylosaurid Akainacephalus suggests multiple ankylosaurid emigration events from Asia to Laramidia during the Late Cretaceous.

(5) Together with some anklylosaurid dinosaurs from northern Laramidia, including Dyoplosaurus acutossquameus and Scolosaurus cutleri (both ~ 77 Ma), Akainacephalus represents one of the oldest known ankylosaurid dinosaurs from the Late Cretaceous of western North America (~76 Ma).

New Dinosaur Name: Akainacephalus johnsoni

  • The first part of the name, Akaina, is a Greek word that can be translated to spike or thorn. The second part of the name cephalus means head, and the epithet johnsoni honors Randy Johnson, a dedicated paleontology volunteer at the Natural History Museum of Utah who prepared the specimen’s skull.

Size

  • Akainacephalus, is a medium-sized dinosaur, and was 13-16 feet long (4-5 meters) and was 3 ½ feet tall (1 — 1.5 meters) at the hips.

Relationships

  • Akainacephalus belongs to a group of herbivorous armored dinosaurs called anklosaurids that lived in Asia and western North America during the Late Cretaceous Period (100-66 million years ago). One of the unique features of ankylosaurid dinosaurs is the presence of a characteristic bony tail club.

Anatomy

  • Akainacephalus walked on four legs, which were positioned directly underneath his body.
  • Akainacephalus was covered in bony armor from head to tail, with various sized and shaped bony plates, called osteoderms, which are thought to provide protection.
  • Akainacephalus is characterized by its elaborate covering of spikes and horns on the skull, as well a large bony club at the end of its tail.
  • Akainacephalus presumably had small, leaf-shaped teeth for eating plants. These fell out of the jaw after death, but before the skeleton was buried by sediment.

Age and Geography

  • Akainacephalus lived during the upper Campanian stage of the Late Cretaceous Period, which spanned from approximately 84 million to 72 million years ago. This animal lived about 76 million years ago.
  • Akainacephalus was discovered in 76 Ma old rocks of the Kaiparowits Formation, a geological/stratigraphic unit exposed in southern Utah consisting of sedimentary rocks deposited by rivers and streams.

Discovery & Excavation

  • Akainacephalus was first discovered in 2008 during a museum-led paleontological expedition in a remote area of BLM-administered Grand Staircase-Escalante National Monument (GSENM) in Kane County, southern Utah, USA. The site was discovered by BLM employee Scott Richardson.
  • The bones of Akainacephalus that were discovered include a complete skull, bony armor that includes neck rings and spiked plates, many vertebrae, forelimb and hindlimb bones, and a near complete tail with tail club.
  • Akainacephalus was found together with skeletons of several other animals at the same site, including a duck-bill dinosaur (Gryposaurus), a recently-described species of turtle (Arvinachelys), and a yet unnamed relative of alligators and caimans).
  • Akainacephalus is permanently housed in the collections of the Natural History Museum of Utah at the Rio Tinto Center in Salt Lake City and on public display at the museum’s Past Worlds exhibit.
  • These discoveries are the result of an ongoing collaboration between the Natural History Museum of Utah and the Bureau of Land Management.

Preparation

  • It required almost four years to fully prepare all of the bones of Akainacephalus.
  • Preparation of the skull was done by museum volunteer Randy Johnson, who is honored in the new name, Akainacephalus johnsoni

Credits: Sciencedaily.com