пятница, 11 января 2019 г.

Unpublished 360° picture of the hidden side of the Moon


CLEP – China Lunar Exploration Program logo.


Jan. 11, 2019



360° picture of the hidden side of the Moon

The Chinese lunar probe sent an impressive panoramic photo of its arrival location, showing a gray landscape dotted with craters.



Sequence of landing pictures by Chang’e-4 onboard camera. Image Credits:CNSA/CLEP

The Chang’e-4 mission succeeded, on January 3rd, the first smooth landing of the history on this hemisphere of the Moon which turns permanently back to the Earth. This is a crucial step in China’s ambitious space program. A small wheeled remote-controlled robot Yutu-2 (“Jade Bunny 2”) has left the lander and is moving on the lunar surface to perform analyzes.



Chang’e-4 landing (Onboard Camera View)

A camera, installed on the probe Chang’e-4, took a picture released Friday by China National Space Agency CNSA (China National Space Administration).



Image above: The 360-degree panoramic image shows a gray lunar surface, part of the probe and the little robot with the marks left by its wheels. “The researchers completed the preliminary analysis of the lunar surface topography around the moon landing site based on the image taken by the camera,” said the CNSA. Image Credits: CLEP/CNSA.


Extremely hot temperatures


The Chang’e-4 probe, the Jade Bunny 2, and the Queqiao satellite responsible for returning the information to Earth “are in a stable state and all programs are proceeding as planned,” the statement said.



Chang’e 4 lander-rover relayed back via satellite relay.Image Credits: CASC/CNSA

The small 140 kg remote-controlled robot resumed its activity on Thursday after being put on standby for several days to avoid the extremely hot temperatures that prevailed on the lunar surface.


This is the second time China has sent a machine to explore the moon after the first Yutu rover in 2013.


Related article:


China’s Yutu-2 rover Enters Standby Mode for ‘Noon Nap’ as Chang’e 4 Tests Continue
https://orbiterchspacenews.blogspot.com/2019/01/chinas-yutu-2-rover-enters-standby-mode.html


For more information about China Aerospace Science and Technology Corporation (CASC), visit: http://english.spacechina.com/n16421/index.html


For more information about China National Space Administration (CNSA), visit: http://www.cnsa.gov.cn/


Images (mentioned), Video, Text, Credits: CNSA/CLEP/AFP/SciNews/Orbiter.ch Aerospace/Roland Berga.


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Team of telescopes finds X-ray engine inside mysterious supernova



ESA – Integral Mission patch / ESA – XMM-Newton Mission patch.


11 January 2019


ESA’s high-energy space telescopes Integral and XMM-Newton have helped to find a source of powerful X-rays at the centre of an unprecedentedly bright and rapidly evolving stellar explosion that suddenly appeared in the sky earlier this year.


The ATLAS telescope in Hawaii first spotted the phenomenon, since then named AT2018cow, on 16 June. Soon after that, astronomers all over the world were pointing many space- and ground-based telescopes towards the newly found celestial object, located in a galaxy some 200 million light years away.



Supernova host galaxy

They soon realised this was something completely new. In only two days the object exceeded the brightness of any previously observed supernova – a powerful explosion of an aging massive star that expels most of its material into the surrounding space, sweeping up the interstellar dust and gases in its vicinity.


A new paper, accepted for publication in the Astrophysical Journal, presents the observations from the first 100 days of the object’s existence, covering the entire electromagnetic spectrum of the explosion from radio waves to gamma rays.


The analysis, which includes observations from ESA’s Integral and XMM-Newton, as well as NASA’s NuSTAR and Swift space telescopes, found a source of high-energy X-rays sitting deep inside the explosion.


The behaviour of this source, or engine, as revealed in the data, suggests that the strange phenomenon could either be a nascent black hole or neutron star with a powerful magnetic field, sucking in the surrounding material.


“The most exciting interpretation is that we might have seen for the first time the birth of a black hole or a neutron star,” says Raffaella Margutti of Northwestern University, USA, lead author of the paper.


“We know that black holes and neutron stars form when stars collapse and explode as a supernova, but never before have we seen one right at the time of birth,” adds co-author Indrek Vurm of Tartu Observatory, Estonia, who worked on modelling the observations.



Supernova on 17 August

The AT2018cow explosion was not only 10 to 100 times brighter than any other supernova previously observed: it also reached peak luminosity much faster than any other previously known event – in only a few days compared to the usual two weeks.


Integral made its first observations of the phenomenon about five days after it had been reported and kept monitoring it for 17 days. Its data proved crucial for the understanding of the strange object.


“Integral covers a wavelength range which is not covered by any other satellite,” says Erik Kuulkers, Integral project scientist at ESA. “We have a certain overlap with NuSTAR in the high-energy X-ray part of the spectrum but we can see higher energies, too.”


So while data from NuSTAR revealed the hard X-ray spectrum in great detail, with Integral the astronomers were able to see the spectrum of the source entirely, including its upper limit at soft gamma-ray energies.


“We saw a kind of a bump with a sharp cut-off in the spectrum at the high-energy end,” says Volodymyr Savchenko, an astronomer at the University of Geneva, Switzerland, who worked on the Integral data. “This bump is an additional component of the radiation released by this explosion, shining through an opaque, or optically thick, medium.”


“This high-energy radiation most likely came from an area of very hot and dense plasma surrounding the source,” adds Carlo Ferrigno, also of the University of Geneva.



Supernova evolution in X-rays

Because Integral kept monitoring the AT2018cow explosion over a longer period of time, its data was also able to show that the high-energy X-ray signal was gradually fading.


Raffaella explains that this high-energy X-ray radiation that went away was the so-called reprocessed radiation – radiation from the source interacting with material ejected by the explosion. As the material travels away from the centre of the explosion, the signal gradually wanes and eventually disappears completely.


In this signal, however, the astronomers were able to find patterns typical of an object that draws in matter from its surroundings – either a black hole or a neutron star.



ESA’s high-energy space telescopes Integral

“This is the most unusual thing that we have observed in AT2018cow and it’s definitely something unprecedented in the world of explosive transient astronomical events,” says Raffaella.


Meanwhile, XMM-Newton looked at this unusual explosion twice over the first 100 days of its existence. It detected the lower-energy part of its X-ray emission, which, according to the astronomers, comes directly from the engine at the core of the explosion. Unlike the high-energy X-rays coming from the surrounding plasma, the lower-energy X-rays from the source are still visible.


The astronomers plan to use XMM-Newton to perform a follow-up observation in the future, which will allow them to understand the source’s behaviour over a longer period of time in greater detail.



XMM-Newton X-ray Observatory

“We are continuing to analyse the XMM-Newton data to try to understand the nature of the source,” says co-author Giulia Migliori of University of Bologna, Italy, who worked on the X-ray data. “Accreting black holes leave characteristic imprints in X-rays, which we might be able to detect in our data.” 


“This event was completely unexpected and it shows that there is a lot of which we don’t completely understand,” says Norbert Schartel, ESA’s XMM-Newton project scientist. “One satellite, one instrument alone, would never be able to understand such a complex object. The detailed insights we were able to gather into the inner workings of the mysterious AT2018cow explosion were only achievable thanks to the broad cooperation and combination of many telescopes.”


Notes for editors:


“An embedded X-ray source shines through the aspherical AT2018cow: revealing the inner workings of the most luminous fast-evolving optical transients” by R. Margutti et al is accepted in Astrophysical Journal:
https://arxiv.org/abs/1810.10720


Related article:


Holy Cow! Mysterious Blast Studied with NASA Telescopes
https://orbiterchspacenews.blogspot.com/2019/01/holy-cow-mysterious-blast-studied-with.html


Related links:


ESA’s Integral: http://sci.esa.int/integral/


ESA’s XMM-Newton: http://sci.esa.int/xmm-newton/


Text, Credits:ESA/Markus Bauer/Norbert Schartel/Erik Kuulkers/INAF–Institute of Radioastronomy, University of Bologna/Giulia Migliori/Department of Astronomy, University of Geneva/Carlo Ferrigno/Volodymyr Savchenko/University of Tartu/Indrek Vurm/Department of Physics and Astronomy, Northwestern University/Raffaella Margutti/Images: W. M. Keck Observatory/R. Margutti/Animation: Courtesy of R. Margutti et al. (2019).


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SpaceX – IRIDIUM-8 Mission Success


SpaceX – Iridium NEXT VIII Mission patch.


Jan. 11, 2019



Falcon 9 carrying Iridium NEXT VIII lift off

On Friday, January 11 at 7:31 a.m. PST, 15:31 UTC, SpaceX successfully launched the eighth and final set of satellites in a series of 75 total satellites for Iridium’s next generation global satellite constellation, Iridium NEXT.



IRIDIUM-8 MISSION

Falcon 9’s first stage delivered the second stage to its targeted orbit followed by deployment of all 10 Iridium NEXT satellites approximately 1 hour and 12 minutes after launch.


Following stage separation, the first stage of Falcon 9 successfully landed on SpaceX’s “Just Read the Instructions” droneship stationed in the Pacific Ocean. Falcon 9’s first stage for the Iridium-8 mission previously supported the Telstar 18 VANTAGE mission in September 2018.


A SpaceX Falcon 9 rocket launches 10 satellites (Iridium Next 66-75) for the Iridium next mobile communications fleet.



Iridium NEXT satellite

Iridium will use its new satellite network to provide improved communications services to more than a million customers across a variety of industries, including expanded services for the so-called “Internet of Things”—smart devices that need their own communications network to connect to the internet.


For more information about SpaceX, visit: https://www.spacex.com/


For more information about Iridium NEXT, visit: https://www.iridium.com/network/iridium-next/


Images, Video, Text, Credits: SpaceX/Iridium/Orbiter.ch Aerospace/Roland Berga.


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Beech trees in Ohio are dying and nobody’s sure why

A confounding new disease is killing beech trees in Ohio and elsewhere, and plant scientists are sounding an alarm while looking for an explanation.











Beech trees in Ohio are dying and nobody's sure why
Intense effort underway to find culprit behind rapid disease spread
[Credit: Ohio State University]

In a study published in the journal Forest Pathology, researchers and naturalists from The Ohio State University and metroparks in northeastern Ohio report on the emerging “beech leaf disease” epidemic, calling for speedy work to find a culprit so that work can begin to stop its spread.


Already, the disease has been found in 11 Ohio counties, eight Pennsylvania counties and five counties in Ontario, Canada. It’s characterized by dark-green “bands” that appear between the veins of the trees’ leaves and provide the first hint that the tree is diseased. In later stages, leaves become uniformly darker, shrunken, crinkly and leathery. Affected limbs stop forming buds and, over time, the tree dies. Young trees seem to be particularly vulnerable.


“It’s hard at this point to say where this disease will go, but it has all the hallmarks of something like emerald ash borer or sudden oak death, threats to trees that start slowly and quickly pick up speed. We seem to be in that rapid expansion phase right now,” said senior researcher Pierluigi “Enrico” Bonello, an Ohio State professor of plant pathology.


From 2012 to 2016, the disease spread in one Ohio county at almost 1,250 acres a year. The threat is significant in Ohio and throughout more than 30 states in the eastern U.S., where beech trees are common and serve as habitats for a variety of animal species and as food for woodland birds and mammals, including squirrels and bears.


If just half of American beech trees in Ohio were lost, it would come at environmental costs of approximately $225 million, according to an estimate in the new paper that takes into account various factors, including the trees’ role in removing carbon from the atmosphere, maintaining biodiversity, furnishing habitat for wildlife, aiding in water purification, providing aesthetic and recreational value as well as other ecosystem services.


Scientists can’t be sure yet what is causing beech leaf disease, but researchers at Ohio State think that the symptoms point to a microbe rather than an insect. Based on that theory, work is underway to look for an explanation by comparing DNA and RNA found on diseased tree leaves to that found on healthy trees.











Beech trees in Ohio are dying and nobody's sure why
Beech leaf disease symptoms include dark banding between the veins in early stages,
followed by crinkling leaves [Credit: Forest Pathology, Ohio State]

Bonello and graduate student Carrie Ewing, lead author of the new paper on the disease, are employing molecular techniques that can identify tiny microbial differences between trees with beech leaf disease and those without.


“The hope is to find a needle in one haystack — the diseased trees — by comparing it with other haystacks, or non-symptomatic trees,” Bonello said. “It’s all about subtracting out all the things they have in common and finding what doesn’t match up.”


In particular, they’re looking for evidence showing whether the disease is bacterial, fungal, viral or possibly caused by a phytoplasma.


“We’re really not 100 percent sure that it’s a microbe causing this, but the symptoms resemble those of other plant diseases caused by microorganisms,” Ewing said. “There are no infestations or boreholes, or chewing of the leaves like you’d typically see if the disease was caused by an insect.”


That said, some other research has pointed to a microscopic worm, or nematode, as a possible culprit.


In addition to American beech trees, or Fagus grandifolia, the disease has been reported in European (F. sylvatica) and Oriental (F. orientalis) species in nurseries and at Holden Arboretum in northeastern Ohio.


This is worrisome because it appears to mean that the risk of disease extends beyond a single species, putting more trees in more areas of the world under threat, Bonello said.


Until scientists determine what is causing beech leaf disease, there’s little they can offer in the way of specific recommendations to stop its spread. Bonello and Ewing are hopeful their work might produce some answers by this summer.


“In general, we know it’s not a good idea to move symptomatic plant material, but beyond that we can’t give any recommendations in terms of what might inhibit this disease,” Bonello said.


Constance Hausman, an ecologist with Cleveland Metroparks and one of the authors of the paper, said it was first discovered in that park system in northeast Cuyahoga County in 2014 and has since spread throughout the entire park district. Thus far, there is no documented evidence of trees developing resistance or recovering from the disease, she said.


“Beech trees are a significant food and habitat resource for wildlife. We can’t treat or manage our beech forests effectively if we don’t know what is causing the decline,” Hausman said.


Other study authors were John Pogacnik of Lake Metroparks in Ohio, who first spotted beech leaf disease in 2012, and Jason Slot, an Ohio State assistant professor of fungal evolutionary genomics.


Author: Misti Crane | Source: Ohio State University [January 09, 2019]



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T. rex bite ‘no match for a finch’

Tyrannosaurus rex, renowned for being one of the most fearsome creatures to have ever lived, evolved a bite that was less impressive in relation to its body size than a tiny Galapagos ground finch, scientists say.











T. rex bite 'no match for a finch'
Bite me: The Galapagos large ground finch squares off against the T-rex [Credit: PA]

New analysis by scientists at the University of Reading and the University of Lincoln has shown the evolution of T. rex was not led by a strong need for a bone-crushing bite to kill its prey. Instead, it had a bite force (57,000 Newtons) that was completely average for its body mass (8 tonnes) and which evolved gradually over tens of millions of years.


Comparatively, a Galapagos large ground finch was found to have the most powerful bite in relation to its body size of all the animals in the study, packing an impressive 70N of force, despite weighing just 33 grammes. This makes the bite force of the finch about 320 times more powerful, pound-for-pound, than T. rex. Moreover, the finch evolved its mega-bite relatively quickly, in less than one million years.


The research also suggests human intelligence may have led to us having an extremely weak bite. This is owing to the evolution of our larger brains taking up space in our heads where the muscles critical for hard biting would otherwise be.


Dr. Manabu Sakamoto, biological scientist at the University of Reading and lead author of the study, said: “The image of T. rex with its fierce jaws has helped it become the most iconic of dinosaurs, but our research shows its bite was relatively unremarkable. Bite force was not what gave T. rex its evolutionary advantage, as was previously presumed.


“Large predators like T. rex could generate enough bite force to kill its prey and crush bone just by being large, not because they had a disproportionately powerful bite. This counters the idea that an exceptionally strong need for a powerful bite drove these ancient beasts to evolve bone-crushing bite forces.”



Dr. Chris Venditti, University of Reading, co-author on the study, said: “Our research provides new insight into the latest theories about the speed and drivers of evolution. It also allows us to create some fascinating hypothetical match-ups.


“The proclaimed ‘King of the Dinosaurs’ would be no match for a finch in a fight, if they were the same size.”


The authors argue that the study, published in the Royal Society journal Proceedings B, shows the course of evolutionary history should not be ignored when looking at how animals developed distinctive traits.


The scientists used supercomputers to analyse the largest ever collection of bite force data from 434 species both extinct and surviving, including reptiles, birds and mammals. They investigated the theory that animals with more powerful bites were forced to rapidly evolve that way owing to changes to their diets.


They instead found that the bite power of most of these animals developed proportionally to evolutionary changes to their body size over time, with only some seeing their bite forces develop at a faster rate than other changes.


Accelerated bursts of bite power evolution were seen in some animals, especially finches – a species famously first noted as an example of natural selection by Charles Darwin. However, expected increases along with body size during the passage of time was seen to be the most common driver of this trait.


The team even observed more dramatic reductions in bite forces during evolution than increases. This was true for early humans, whose bite power decreased rapidly despite their body size increasing over time.


Dr. Sakamoto said: “An evolutionary trade-off with increasing brain size in humans may be the reason that our bite power is pretty pathetic.


“Once we learnt to cook food, bite power became even less important. In effect, we evolved the cooking pot as our way of making our food easier to swallow. This is in line with other studies showing that humans chew their food less than other animals.”


Source: University of Reading [January 09, 2019]



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15-metre-long ancient whale Basilosaurus isis was top marine predator

The stomach contents of ancient whale Basilosaurus isis suggest it was an apex predator, according to a study published in the open-access journal PLOS ONE by Manja Voss from the Museum für Naturkunde Berlin, Germany, and colleagues.











15-metre-long ancient whale Basilosaurus isis was top marine predator
Examination of the bones found in Egypt suggest Basilosaurus was a top predator that fed
on other ancient whales [Credit: Pavel.Riha.CB]

The authors uncovered an adult B. isis specimen in 2010 in the Wadi Al Hitan (“Valley of Whales”) site in Cairo, Egypt. This site was once a shallow sea during the late Eocene period and is remarkable for its wealth of marine fossils. While excavating this main B. isis specimen, the authors also revealed the remains of sharks, large bony fish, and, most numerously, bones from Dorudon atrox, a smaller species of ancient whale.
The Basilosaurus skeleton was distinct from other skeletons in the cluster, containing pointed B. isis incisors and sharp cheek teeth as well as bones. Most of the fish, and Dorudon whale remains showed signs of breakage and bite marks, were fragmented, and tended to be clustered within the body cavity of the B. isis specimen.











15-metre-long ancient whale Basilosaurus isis was top marine predator
Skeletons of Basilosaurus isis (A; CGM 42195) and Dorudon atrox (B; CGM 42183 and UM 97512, 100146, 101215,
101222) from Wadi Al Hitan, Egypt, as exhibited at the University of Michigan. Both are adult, fully grown, and
 illustrated at the same scale (scale bar equals 1 meter). CGM 42195 shows a cast of a 15 metre
long B. isis specimen [Credit: Voss et al., 2019]

One hypothesis to explain the clustering of these remains was that D. atrox had scavenged the B. isis carcass and fish. However, the D. atrox were juveniles, capable only of drinking mother’s milk. Bite marks on prey skulls also indicated predation rather than scavenging, since predators commonly target the head. The authors therefore position B. isis as a top predator which ate its prey live, rather than by scavenging. They propose that the remains of fish and juvenile D. atrox in the cluster are remnants of previous B. isis meals, while the teeth of sharks indicate postmortem scavenging.
Voss and colleagues draw a comparison with the modern-day killer whale (Orcinus orca), another toothed whale apex predator which often feeds on smaller whales and frequently hunts humpback whale calves during humpback calving season. The authors hypothesize that the Wadi Al Hitan site was a whale calving site for prey whale Dorudon, making it a hunting site for top predator B. isis during the late Eocene.


Source: PLOS [January 09, 2019]



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Reconstruction of trilobite ancestral range in the southern hemisphere

The first appearance of trilobites in the fossil record dates to 521 million years ago in the oceans of the Cambrian Period, when the continents were still inhospitable to most life forms. Few groups of animals adapted as successfully as trilobites, which were arthropods that lived on the seabed for 270 million years until the mass extinction at the end of the Permian approximately 252 million years ago.











Reconstruction of trilobite ancestral range in the southern hemisphere
Brazilian researchers used biogeographic analysis to study trilobites, arthropods that became
extinct over 252 million years ago [Credit: Dlloyd/WikiCommons]

The longer ago organisms lived, the more rare are their fossils and the harder it is to understand their way of life; paleontologists face a daunting task in endeavoring to establish evolutionary relationships in time and space.


Surmounting the difficulties inherent in the investigation of a group of animals that lived such a long time ago, Brazilian scientists affiliated with the Biology Department of São Paulo State University’s Bauru School of Sciences (FC-UNESP) and the Paleontology Laboratory of the University of São Paulo’s Ribeirão Preto School of Philosophy, Science and Letters (FFCLRP-USP) have succeeded for the first time in inferring paleobiogeographic patterns among trilobites.


Paleobiogeography is a branch of paleontology that focuses on the distribution of extinct plants and animals and their relations with ancient geographic features. The study was conducted by Fábio Augusto Carbonaro, a postdoctoral researcher at UNESP’s Bauru Macroinvertebrate Paleontology Laboratory (LAPALMA) headed by Professor Renato Pirani Ghilardi. Other participants included Max Cardoso Langer, a professor at FFCLRP-USP, and Silvio Shigueo Nihei, a professor at the same university’s Bioscience Institute (IB-USP).


The researchers analyzed the morphological differences and similarities of the 11 species of trilobites described so far in the genus Metacryphaeus; these trilobites lived during the Devonian between 416 million and 359 million years ago (mya) in the cold waters of the sea that covered what is now Bolivia, Peru, Brazil, the Malvinas (Falklands) and South Africa.


The Devonian Period is subdivided into seven stages. Metacryphaeus lived during the Lochkovian (419.2-410.8 mya) and Pragian (410.8- 407.6 mya) stages, which are the earliest Devonian stages.


The results of the research were published in Scientific Reports and are part of the project “Paleobiogeography and migratory routes of paleoinvertebrates of the Devonian in Brazil”, which is supported by São Paulo Research Foundation -FAPESP and Brazil’s National Council for Scientific and Technological Development (CNPq). Ghilardi is the project’s principal investigator.


“When they became extinct in the Permian, 252 million years ago, the trilobites left no descendants. Their closest living relatives are shrimps, and, more remotely, spiders, scorpions, sea spiders and mites,” Ghilardi said.


Trilobite fossils are found abundantly all over the world, he explained – so abundantly that they are sometimes referred to as the cockroaches of the sea. The comparison is not unwarranted because anatomically, the trilobites resemble cockroaches. The difference is that they were not insects and had three longitudinal body segments or lobes (hence the name).


In the northern hemisphere, the trilobite fossil record is very rich. Paleontologists have so far described ten orders comprising over 17,000 species. The smallest were 1.5 millimeters long, while the largest were approximately 70 cm long and 40 cm wide. Perfectly preserved trilobites can be found in some regions, such as Morocco. These can be beautiful when used to create cameos or intaglio jewelry. Trilobite fossils from Brazil, Peru and Bolivia, in contrast, are often poorly preserved, consisting merely of the impressions left in benthic mud by their exoskeletons.


“Although their state of preservation is far from ideal, there are thousands of trilobite fossils in the sediments that form the Paraná basin in the South region of Brazil, and the Parnaíba basin along the North-Northeast divide,” said Ghilardi, who also chairs the Brazilian Paleontology Society.


According to Ghilardi, their poor state of preservation could be due to the geological conditions and climate prevailing in these regions during the Paleozoic Era, when the portions of dry land that would one day form South America were at the South Pole and entirely covered by ice for prolonged periods.


During the Devonian, South America and Africa were connected as part of the supercontinent Gondwana. South Africa was joined with Uruguay and Argentina in the River Plate region, and Brazil’s southern states were continuous with Namibia and Angola.


Parsimonious analysis


The research began with an analysis of 48 characteristics (size, shape and structure of organs and anatomical parts) found in some 50 fossil specimens of the 11 species of Metacryphaeus.


“In principle, these characteristics serve to establish their phylogeny – the evolutionary history of all species in the universe, analyzed in terms of lines of descent and relationships among broader groups,” Ghilardi said.


Known as a parsimonious analysis, this method is widely used to establish relationships among organisms in a given ecosystem, and in recent years, it has also begun to be used in the study of fossils.


According to Ghilardi, parsimony, in general, is the principle that the simplest explanation of the data is the preferred explanation. In the analysis of phylogeny, it means that the hypothesis regarding relationships that requires the smallest number of characteristic changes between the species analyzed (in this case, trilobites of the genus Metacryphaeus) is the one that is most likely to be correct.


The biogeographic contribution to the study was made by Professor Nihei, who works at IB-USP as a taxonomist and insect systematist. The field of systematics is concerned with evolutionary changes between ancestries, while taxonomy focuses on classifying and naming organisms.


“Biogeographic analysis typically involves living groups the ages of which are estimated by molecular phylogeny, or the so-called molecular clock, which estimates when two species probably diverged on the basis of the number of molecular differences in their DNA. In this study of trilobites, we used age in a similar manner, but it was obtained from the fossil record,” Nihei said.


“The main point of the study was to use fossils in a method that normally involves molecular biogeography. Very few studies of this type have previously involved fossils. I believe our study paves the way for a new approach based on biogeographic methods requiring a chronogram [a molecularly dated cladogram] because this chronogram can also be obtained from fossil taxa such as those studied by paleontologists, rather than molecular cladograms for living animals.”


As a vertebrate paleontologist who specializes in dinosaurs, Langer acknowledged that he knows little about trilobites but a great deal about the modern computational techniques used in parsimonious analysis, on which his participation in the study was based. “I believe the key aspect of this study, and the reason it was accepted for publication in as important a journal as Scientific Reports, is that it’s the first ever use of parsimony to understand the phylogeny of a trilobite genus in the southern hemisphere,” he said.


Gondwanan dispersal


The results of the paleobiogeographical analyses reinforce the pre-existing theory that Bolivia and Peru formed the ancestral home of Metacryphaeus.


“The models estimate a 100% probability that Bolivia and Peru formed the ancestral area of the Metacryphaeus clade and most of its internal clades,” Ghilardi said. Confirmation of the theory shows that parsimonious models have the power to suggest the presence of clades at a specific moment in the past even when there are no known physical records of that presence.


In the case of Metacryphaeus, the oldest records in Bolivia and Peru date from the early Pragian stage (410.8-407.6 mya), but the genus is believed to have evolved in the region during the Lochkovian stage (419.2-410.8 mya).


Parsimony, therefore, suggests Metacryphaeus originated in Bolivia and Peru some time before 410.8 mya but not earlier than 419.2 mya. In any event, it is believed to be far older than any known fossils.


According to Ghilardi, the results can be interpreted as showing that the adaptive radiation of Metacryphaeus to other areas of western Gondwana occurred during episodes of marine transgression in the Lochkovian-Pragian, when the sea flooded parts of Gondwana.


“The dispersal of Metacryphaeus trilobites during the Lochkovian occurred from Bolivia and Peru to Brazil – to the Paraná basin, now in the South region, and the Parnaíba basin, on the North-Northeast divide – and on toward the Malvinas/Falklands, while the Pragian dispersal occurred toward South Africa,” he said.


Fossil trilobites have been found continuously in the Paraná basin in recent decades. Trilobites collected in the late nineteenth century in the Parnaíba basin were held by Brazil’s National Museum in Rio de Janeiro, which was destroyed by fire in September 2018.


“These fossils haven’t yet been found under the rubble and it’s likely that nothing is left of them. They were mere shell impressions left in the ancient seabed. Even in petrified form, they must have dissolved in the blaze,” Ghilardi said.


Source: Fundação de Amparo à Pesquisa do Estado de São Paulo [January 09, 2019]




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Illuminating women’s role in the creation of medieval manuscripts

During the European Middle Ages, literacy and written texts were largely the province of religious institutions. Richly illustrated manuscripts were created in monasteries for use by members of religious institutions and by the nobility. Some of these illuminated manuscripts were embellished with luxurious paints and pigments, including gold leaf and ultramarine, a rare and expensive blue pigment made from lapis lazuli stone.











Illuminating women's role in the creation of medieval manuscripts
Dental calculus on the lower jaw a medieval woman entrapped lapis lazuli pigment
[Credit: Christina Warinner]

In a study published in Science Advances, an international team of researchers led by the Max Planck Institute for the Science of Human History and the University of York shed light on the role of women in the creation of such manuscripts with a surprising discovery — the identification of lapis lazuli pigment embedded in the calcified dental plaque of a middle-aged woman buried at a small women’s monastery in Germany around 1100 AD. Their analysis suggests that the woman was likely a painter of richly illuminated religious texts.
A quiet monastery in central Germany


As part of a study analyzing dental calculus — tooth tartar or dental plaque that fossilizes on the teeth during life — researchers examined the remains of individuals who were buried in a medieval cemetery associated with a women’s monastery at the site of Dalheim in Germany. Few records remain of the monastery and its exact founding date is not known, although a women’s community may have formed there as early as the 10th century AD. The earliest known written records from the monastery date to 1244 AD. The monastery is believed to have housed approximately 14 religious women from its founding until its destruction by fire following a series of 14th century battles.











Illuminating women's role in the creation of medieval manuscripts
Magnified view of lapis lazuli particles embedded within medieval dental calculus
[Credit: Monica Tromp]

One woman in the cemetery was found to have numerous flecks of blue pigment embedded within her dental calculus. She was 45-60 years old when she died around 1000-1200 AD. She had no particular skeletal pathologies, nor evidence of trauma or infection. The only remarkable aspect to her remains was the blue particles found in her teeth. “It came as a complete surprise — as the calculus dissolved, it released hundreds of tiny blue particles,” recalls co-first author Anita Radini of the University of York. Careful analysis using a number of different spectrographic methods — including energy dispersive X-ray spectroscopy (SEM-EDS) and micro-Raman spectroscopy — revealed the blue pigment to be made from lapis lazuli.


A pigment as rare and expensive as gold


“We examined many scenarios for how this mineral could have become embedded in the calculus on this woman’s teeth,” explains Radini. “Based on the distribution of the pigment in her mouth, we concluded that the most likely scenario was that she was herself painting with the pigment and licking the end of the brush while painting,” states co-first author Monica Tromp of the Max Planck Institute for the Science of Human History.


The use of ultramarine pigment made from lapis lazuli was reserved, along with gold and silver, for the most luxurious manuscripts. “Only scribes and painters of exceptional skill would have been entrusted with its use,” says Alison Beach of Ohio State University, a historian on the project.


The unexpected discovery of such a valuable pigment so early and in the mouth of an 11th century woman in rural Germany is unprecedented. While Germany is known to have been an active center of book production during this period, identifying the contributions of women has been particularly difficult. As a sign of humility, many medieval scribes and painters did not sign their work, a practice that especially applied to women. The low visibility of women’s labor in manuscript production has led many modern scholars to assume that women played little part in it.











Illuminating women's role in the creation of medieval manuscripts
Foundations of the church associated with a medieval women’s religious community at Dalheim, Germany
[Credit: Christina Warinner]

The findings of this study not only challenge long-held beliefs in the field, they also uncover an individual life history. The woman’s remains were originally a relatively unremarkable find from a relatively unremarkable place, or so it seemed. But by using these techniques, the researchers were able to uncover a truly remarkable life history.


“She was plugged into a vast global commercial network stretching from the mines of Afghanistan to her community in medieval Germany through the trading metropolises of Islamic Egypt and Byzantine Constantinople. The growing economy of 11th century Europe fired demand for the precious and exquisite pigment that traveled thousands of miles via merchant caravan and ships to serve this woman artist’s creative ambition,” explains historian and co-author Michael McCormick of Harvard University.


“Here we have direct evidence of a woman, not just painting, but painting with a very rare and expensive pigment, and at a very out-of-the way place,” explains Christina Warinner of the Max Planck Institute for the Science of Human History, senior author on the paper. “This woman’s story could have remained hidden forever without the use of these techniques. It makes me wonder how many other artists we might find in medieval cemeteries — if we only look.”


Source: Max Planck Institute for the Science of Human History [January 09, 2019]



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Solving the ancient mysteries of Easter Island

The ancient people of Rapa Nui (Easter Island, Chile) built their famous ahu monuments near coastal freshwater sources, according to a team of researchers including faculty at Binghamton University, State University of New York.











Solving the ancient mysteries of Easter Island
Examples of the Easter Island statues, or moai [Credit: Dale Simpson, Jr.]

The island of Rapa Nui is well-known for its elaborate ritual architecture, particularly its numerous statues (moai) and the monumental platforms that supported them (ahu.) Researchers have long wondered why ancient people built these monuments in their respective locations around the island, considering how much time and energy was required to construct them. A team of researchers including Binghamton University anthropologist Carl Lipo used quantitative spatial modeling to explore the potential relations between ahu construction locations and subsistence resources, namely, rock mulch agricultural gardens, marine resources, and freshwater sources–the three most critical resources on Rapa Nui. Their results suggest that ahu locations are explained by their proximity to the island’s limited freshwater sources.
“The issue of water availability (or the lack of it) has often been mentioned by researchers who work on Rapa Nui/Easter Island,” said Lipo. “When we started to examine the details of the hydrology, we began to notice that freshwater access and statue location were tightly linked together. It wasn’t obvious when walking around–with the water emerging at the coast during low tide, one doesn’t necessarily see obvious indications of water. But as we started to look at areas around ahu, we found that those locations were exactly tied to spots where the fresh groundwater emerges — largely as a diffuse layer that flows out at the water’s edge. The more we looked, the more consistently we saw this pattern. Places without ahu/moai showed no freshwater. The pattern was striking and surprising in how consistent it was. Even when we find ahu/moai in the interior of the island, we find nearby sources of drinking water. This paper reflects our work to demonstrate that this pattern is statistically sound and not just our perception.”



“Many researchers, ourselves included, have long speculated associations between ahu/moai and different kinds of resources, e.g., water, agricultural land, areas with good marine resources, etc.,” said lead author Robert DiNapoli of the University of Oregon. “However, these associations had never been quantitatively tested or shown to be statistically significant. Our study presents quantitative spatial modeling clearly showing that ahu are associated with freshwater sources in a way that they aren’t associated with other resources.”


According to Terry Hunt of the University of Arizona, the proximity of the monuments to freshwater tells us a great deal about the ancient island society.


“The monuments and statues are located in places with access to a resource critical to islanders on a daily basis–fresh water. In this way, the monuments and statues of the islanders’ deified ancestors reflect generations of sharing, perhaps on a daily basis–centered on water, but also food, family and social ties, as well as cultural lore that reinforced knowledge of the island’s precarious sustainability. And the sharing points to a critical part of explaining the island’s paradox: despite limited resources, the islanders succeeded by sharing in activities, knowledge, and resources for over 500 years until European contact disrupted life with foreign diseases, slave trading, and other misfortunes of colonial interests.”


The researchers currently only have comprehensive freshwater data for the western portion of the island and plan to do a complete survey of the island in order to continue to test their hypothesis of the relation between ahu and freshwater.


The paper, “Rapa Nui (Easter Island) monument locations explained by freshwater sources,” was published in PLOS ONE.


Source: Binghamton University [January 10, 2019]



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Sculpted Standing Stones at the base of Tre’r Ceiri Iron Age Hillfort, North Wales,...

Sculpted Standing Stones at the base of Tre’r Ceiri Iron Age Hillfort, North Wales, 4.1.19.











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2019 January 11 Partial Eclipse over Beijing Image Credit…


2019 January 11


Partial Eclipse over Beijing
Image Credit & Copyright: Li Zhaoqi


Explanation: On January 6 the New Moon rose in silhouette with the Sun seen from northeastern Asia. Near maximum, the dramatic partial solar eclipse is captured in this telephoto view through hazy skies. In the foreground, the hill top Wanchun pavilion overlooking central Beijing’s popular Forbidden City hosts eclipse-watching early morning risers. This was the first of five, three solar and two lunar, eclipses for 2019. Next up is a total lunar eclipse during this month’s Full Perigee Moon. At night on January 21, that celestial shadow play will be visible from the hemisphere of planet Earth that includes the Americas, Europe, and western Africa.


∞ Source: apod.nasa.gov/apod/ap190111.html


Dyffryn Ardudwy Burial Chambers, Dyffryn Ardudwy, North Wales, 4.1.19.


Dyffryn Ardudwy Burial Chambers, Dyffryn Ardudwy, North Wales, 4.1.19.











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