вторник, 25 декабря 2018 г.

‘A Balancing Act’, Idol Rock, Brimham Rocks, Yorkshire, 24.12.18.This...

‘A Balancing Act’, Idol Rock, Brimham Rocks, Yorkshire, 24.12.18.

This striking wind and water shaped stone is the product of the last Ice Age.

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2018 December 25 M100: A Grand Design Spiral Galaxy Image…

2018 December 25

M100: A Grand Design Spiral Galaxy
Image Credit: NASA, ESA, Hubble

Explanation: Majestic on a truly cosmic scale, M100 is appropriately known as a grand design spiral galaxy. It is a large galaxy of over 100 billion stars with well-defined spiral arms that is similar to our own Milky Way Galaxy. One of the brightest members of the Virgo Cluster of galaxies, M100 (alias NGC 4321) is 56 million light-years distant toward the constellation of Berenice’s Hair (Coma Berenices). This Hubble Space Telescope image of M100 was taken recently with the Wide Field Camera 3 and accentuates bright blue star clusters and intricate winding dust lanes which are hallmarks of this class of galaxies. Studies of variable stars in M100 have played an important role in determining the size and age of the Universe.

∞ Source: apod.nasa.gov/apod/ap181225.html

Stellar corpse reveals clues to missing stardust

Everything around you – your desk, your laptop, your coffee cup – in fact, even you – is made of stardust, the stuff forged in the fiery furnaces of stars that died before our sun was born. Probing the space surrounding a mysterious stellar corpse, scientists at the University of Arizona have made a discovery that could help solve a long-standing mystery: Where does stardust come from?

Stellar corpse reveals clues to missing stardust
The Butterfly Nebula, also known as the Twin Jet Nebula, is an example of a so-called bipolar planetary nebula. The object
of this study, K4-47, is much less known, but may be similar in appearance. Having nothing to do with planets, a planetary
nebula is a glowing, often colorful, shell of gas and dust shed into space by a dying star at high speed
[Credit: ESA/Hubble & NASA/Judy Schmidt]

When stars die, they seed the cosmos around them with the elements that go on to coalesce into new stars, planets, asteroids and comets. Most everything that makes up Earth, even life itself, consists of elements made by previous stars, including silicon, carbon, nitrogen and oxygen. But this is not the whole story. Meteorites commonly contain traces of a type of stardust that, until now, was believed to form only in exceptionally violent, explosive events of stellar death known as novae or supernovae – too rare to account for the abundance preserved in meteorites.

Researchers at the UA used radio telescopes in Arizona and Spain to observe gas clouds in the young planetary nebula K4-47, an enigmatic object approximately 15,000 light-years from Earth. Classified as a nebula, K4-47 is a stellar remnant, which astronomers believe was created when a star not unlike our sun shed some of its material in a shell of outflowing gas before ending its life as a white dwarf.

To their surprise, the researchers found that some of the elements that make up the nebula – carbon, nitrogen and oxygen – are highly enriched with certain variants that match the abundances seen in some meteorite particles but are otherwise rare in our solar system: so-called heavy isotopes of carbon, nitrogen and oxygen, or 13C15N and 17O, respectively. These isotopes differ from their more common forms by containing an extra neutron inside their nucleus.

Fusing an additional neutron onto an atomic nucleus requires extreme temperatures in excess of 200 million degrees Fahrenheit, leading scientists to conclude those isotopes could only be formed in novae – violent outbursts of energy in aging binary star systems – and supernovae, in which a star blows itself apart in one cataclysmic explosion.

“The models invoking only novae and supernovae could never account for the amounts of 15N and 17O we observe in meteorite samples,” said Lucy Ziurys, senior author of the paper, which is published in the journal Nature. “The fact that we’re finding these isotopes in K4-47 tells us that we don’t need strange exotic stars to explain their origin. It turns out your average garden variety stars are capable of producing them as well.”

In lieu of cataclysmic explosive events forging heavy isotopes, the team suggests they could be produced when an average-size star such as our sun becomes unstable toward the end of its life and undergoes a so-called helium flash, in which super-hot helium from the star’s core punches through the overlaying hydrogen envelope.

“This process, during which the material has to be spewed out and cooled quickly, produces 13C,  15N and 17O,” explained Ziurys, a professor with dual appointments in the UA’s Steward Observatory and Department of Chemistry and Biochemistry. “A helium flash doesn’t rip the star apart like a supernova does. It’s more like a stellar eruption.”

The findings have implications for the identification of stardust and the understanding of how common stars create elements such as oxygen, nitrogen and carbon, the authors said.

The discovery was made possible through a collaboration between disciplines that traditionally have remained relatively separate: astronomy and cosmochemistry. The team used radio telescopes at the Arizona Radio Observatory and Institut de Radioastronomie Millimetrique (IRAM) to observe rotational spectra emitted by the molecules in the K4-47 nebula, which reveal clues about their mass distribution and their identity.

“When Lucy and I started collaborating on this project, we realized that we could reconcile what we found in meteorites and what we observe in space,” said co-author Tom Zega, associate professor of cosmochemistry, planetary materials and astrobiology in the UA’s Lunar and Planetary Laboratory.

The researchers are eagerly awaiting the discoveries that lie ahead for NASA’s OSIRIS-REx asteroid sample return mission, which is led by the UA. Just two weeks ago, the spacecraft arrived at its target asteroid, Bennu, from which it will collect a sample of pristine material in 2020. One of the mission’s major goals is to understand the evolution of Bennu and the origins of the solar system.

“You can think of the grains we find in meteorites as stellar ashes, left behind by stars that had long died when our solar system formed,” Zega said. “We expect to find those pre-solar grains on Bennu – they are part of the puzzle of the history of this asteroid, and this research will help define where the material on Bennu came from.”

“We can now trace where those ashes came from,” Ziurys added. “It’s like an archaeology of stardust.”

“The study of explosive helium burning inside stars will start a new chapter in the story of the origin of the chemical elements,” said Neville “Nick” Woolf, Professor Emeritus at Steward Observatory and the fourth co-author.

The article’s first author is Deborah Schmidt, a doctoral student at the Steward Observatory.

Author: Daniel Stolte | Source: University of Arizona [December 20, 2018]



Faint starlight in Hubble images reveals distribution of dark matter

Astronomers using data from the NASA/ESA Hubble Space Telescope have employed a revolutionary method to detect dark matter in galaxy clusters. The method allows astronomers to “see” the distribution of dark matter more accurately than any other method used to date and it could possibly be used to explore the ultimate nature of dark matter. The results were published in the journal Monthly Notices of the Royal Astronomical Society.

Faint starlight in Hubble images reveals distribution of dark matter
Two massive galaxy clusters — Abell S1063 (left) and MACS J0416.1-2403 (right) — display a soft blue haze, called
intracluster light, embedded among innumerable galaxies. The intracluster light is produced by orphan stars that no
 longer belong to any single galaxy, having been thrown loose during a violent galaxy interaction, and now drift freely
throughout the cluster of galaxies. Astronomers have found that intracluster light closely matches with a map of mass
distribution in the cluster’s overall gravitational field. This makes the blue “ghost light” a good indicator of how invisible
dark matter is distributed in the cluster. Dark matter is a key missing link in our understanding of the structure and evolution
of the universe. Abell S1063 and MACS J0416.1-2403 were the strongest examples of intracluster light providing a much
 better match to the cluster’s mass map than X-ray light, which has been used in the past to trace dark matter
[Credit: NASA, ESA, and M. Montes (University of New South Wales)]

In recent decades astronomers have tried to understand the true nature of the mysterious substance that makes up most of the matter in the Universe — dark matter — and to map its distribution in the Universe. Now two astronomers from Australia and Spain have used data from the Frontier Fields programme of the NASA/ESA Hubble Space Telescope to accurately study the distribution of dark matter.

“We have found a way to ‘see’ dark matter,” explains Mireia Montes (University of New South Wales, Australia), lead author of the study. “We have found that very faint light in galaxy clusters, the intracluster light, maps how dark matter is distributed.”

Intracluster light is a byproduct of interactions between galaxies. In the course of these interactions, individual stars are stripped from their galaxies and float freely within the cluster. Once free from their galaxies, they end up where the majority of the mass of the cluster, mostly dark matter, resides.

“These stars have an identical distribution to the dark matter, as far as our current technology allows us to study,” explained Montes. Both the dark matter and these isolated stars — which form the intracluster light — act as collisionless components. These follow the gravitational potential of the cluster itself. The study showed that the intracluster light is aligned with the dark matter, tracing its distribution more accurately than any other method relying on luminous tracers used so far.

This animation switches between an original image of the galaxy cluster MACS J0416.1–2403, as it was observed by the 

Frontier Field team, and a version, in which the intracluster light (in blue) is highlighted. Intracluster light is a byproduct 

of interactions between galaxies. It can be used to make the distribution of dark matter in galaxy clusters visible 

[Credit: ESA/Hubble, NASA, HST Frontier Fields team (STScI), and M. Montes & I. Trujillo]

This method is also more efficient than the more complex method of using gravitational lensing. While the latter requires both accurate lensing reconstruction and time-consuming spectroscopic campaigns, the method presented by Montes utilises only deep imaging. This means more clusters can be studied with the new method in the same amount of observation time.

The results of the study introduce the possibility of exploring the ultimate nature of dark matter. “If dark matter is self-interacting we could detect this as tiny departures in the dark matter distribution compared to this very faint stellar glow,” highlights Ignacio Trujillo (Instituto de Astrofísica de Canarias, Spain), co-author of the study. Currently, all that is known about dark matter is that it appears to interact with regular matter gravitationally, but not in any other way. To find that it self-interacts would place significant constraints on its identity.

For now, Montes and Trujillo plan to survey more of the original six clusters to see if their method remains accurate. Another important test of their method will be the observation and analysis of additional galaxy clusters by other research teams, to add to the data set and confirm their findings.

The team can also look forward to the application of the same techniques using future space-based telescopes like the NASA/ESA/CSA James Webb Space Telescope, which will have even more sensitive instruments able to resolve faint intracluster light in the distant Universe.

“There are exciting possibilities that we should be able to probe in the upcoming years by studying hundreds of galaxy clusters,” concludes Ignacio Trujillo.

Source: ESA/Hubble Information Centre [December 20, 2018]



Beyond the black hole singularity

Our first glimpses into the physics that exist near the center of a black hole are being made possible using “loop quantum gravity”–a theory that uses quantum mechanics to extend gravitational physics beyond Einstein’s theory of general relativity. Loop quantum gravity, originated at Penn State and subsequently developed by a large number of scientists worldwide, is opening up a new paradigm in modern physics. The theory has emerged as a leading candidate to analyze extreme cosmological and astrophysical phenomena in parts of the universe, like black holes, where the equations of general relativity cease to be useful.

Beyond the black hole singularity
Artist representation of a black hole. The bottom half of the image depicts the black hole which, according to general
relativity, traps everything including light. Effects based on loop quantum gravity, a theory that extends Einsteins general
relativity using quantum mechanics, overcome this tremendous pull and liberate everything (top half of image), thus
providing a concrete avenue for recovery of information previously thought to be lost in the black hole singularity
[Credit: A. Corichi and J. P. Ruiz]

Previous work in loop quantum gravity that was highly influential in the field analyzed the quantum nature of the Big Bang, and now two new papers by Abhay Ashtekar and Javier Olmedo at Penn State and Parampreet Singh at Louisiana State University extend those results to black hole interiors. The papers appear as “Editors’ suggestions” in the journals Physical Review Letters.

“The best theory of gravity that we have today is general relativity, but it has limitations,” said Ashtekar, Evan Pugh Professor of Physics, holder of the Eberly Family Chair in Physics, and director of the Penn State Institute for Gravitation and the Cosmos. “For example, general relativity predicts that there are places in the universe where gravity becomes infinite and space-time simply ends. We refer to these places as ‘singularities.’ But even Einstein agreed that this limitation of general relativity results from the fact that it ignores quantum mechanics.”

At the center of a black hole the gravity is so strong that, according to general relativity, space-time becomes so extremely curved that ultimately the curvature becomes infinite. This results in space-time having a jagged edge, beyond which physics no longer exists–the singularity. Another example of a singularity is the Big Bang.

Asking what happened before the Big Bang is a meaningless question in general relativity, because space-time ends, and there is no before. But modifications to Einstein’s equations that incorporated quantum mechanics through loop quantum gravity allowed researchers to extend physics beyond the Big Bang and make new predictions. The two recent papers have accomplished the same thing for the black hole singularity.

“The basis of loop quantum gravity is Einstein’s discovery that the geometry of space-time is not just a stage on which cosmological events are acted out, but it is itself a physical entity that can be bent,” said Ashtekar. “As a physical entity the geometry of space-time is made up of some fundamental units, just as matter is made up of atoms. These units of geometry–called ‘quantum excitations’–are orders of magnitude smaller than we can detect with today’s technology, but we have precise quantum equations that predict their behavior, and one of the best places to look for their effects is at the center of a black hole.”

According to general relativity, at the center of a black hole gravity becomes infinite so everything that goes in, including the information needed for physical calculations, is lost. This leads to the celebrated ‘information paradox’ that theoretical physicists have been grappling with for over 40 years. However, the quantum corrections of loop quantum gravity allow for a repulsive force that can overwhelm even the strongest pull of classical gravity and therefore physics can continue to exist. This opens an avenue to show in detail that there is no loss of information at the center of a blackhole, which the researchers are now pursuing.

Interestingly, even though loop quantum gravity continues to work where general relativity breaks down–black hole singularities, the Big Bang–its predictions match those of general relativity quite precisely under less extreme circumstances away from the singularity. “It is highly non-trivial to achieve both,” said Singh, associate professor of physics at Louisiana State. “Indeed, a number of investigators have explored the quantum nature of the black hole singularity over the past decade, but either the singularity prevailed or the mechanisms that resolved it unleashed unnatural effects. Our new work is free of all such limitations.”

Source: Penn State University [December 20, 2018]



Lower oxygen levels to impact the oceanic food chain

Tiny fish known to survive where most marine life could not, may no longer be able to thrive under diminishing oxygen levels.

Lower oxygen levels to impact the oceanic food chain
Krill is one of the species determined unable to handle further ocean deoxygenation. They’re very important
in the diets of fishes, squids and whales [Credit: Stephani Gordon, Open Boat Films]

A new study published in Science Advances finds just the slightest change in oxygen level could have tremendous ramifications on the food chain. Rising temperatures are causing mid-water regions with very low oxygen, known as Oxygen Minimum Zones (OMZs), to expand in the eastern tropical North Pacific Ocean. While some organisms in certain regions may be able to adapt, researchers found those living in OMZs likely cannot as they’re already pushed to their physiological limits.

“These animals have evolved a tremendous ability to extract and use the small amount of oxygen available in their environment,” said study author Brad Seibel, Ph.D., professor of biological oceanography at the University of South Florida College of Marine Science. “Even so, we found that natural reductions in oxygen levels of less than 1% were sufficient to exclude most species or alter their distribution.”

Researchers looked at many different types of marine zooplankton, which includes fishes and crustaceans that are essential to the marine food chain. Cyclothone, for example, is among the most abundant vertebrates in the world, while krill are important in the diets of fishes, squids and whales.

With the expansion of OMZs, these species may be pushed into shallower water where there’s more sunlight, higher temperatures and greater risk of predators.

Seibel was chief scientist of the expedition that studied the physiological tolerance of animals across a range of oxygen values. He found that animals in this region had a tremendous tolerance for low oxygen, but that they were living at oxygen values near their evolved limits. Thus, small oxygen changes had a substantial impact on the abundance and distribution of most species. Further climate-related deoxygenation may dramatically alter these marine ecosystems.

Source: University of South Florida [December 20, 2018]



New threat to ozone recovery

Earlier this year, the United Nations announced some much-needed, positive news about the environment: The ozone layer, which shields the Earth from the sun’s harmful ultraviolet radiation, and which was severely depleted by decades of human-derived, ozone-destroying chemicals, is on the road to recovery.

New threat to ozone recovery
MIT researchers have back-tracked chloroform in East Asia using AGAGE measurements and 3-dimensional 
atmospheric transport models [Credit: Xuekun Fang et al. 2018]

The dramatic turnaround is a direct result of regulations set by the 1987 Montreal Protocol, a global treaty under which nearly every country in the world, including the United States, successfully acted to ban the production of chlorofluorocarbons (CFCs), the main agents of ozone depletion. As a result of this sustained international effort, the United Nations projects that the ozone layer is likely to completely heal by around the middle of the century.

But a new MIT study, published in Nature Geoscience, identifies another threat to the ozone layer’s recovery: chloroform — a colorless, sweet-smelling compound that is primarily used in the manufacturing of products such as Teflon and various refrigerants. The researchers found that between 2010 and 2015, emissions and concentrations of chloroform in the global atmosphere have increased significantly.

They were able to trace the source of these emissions to East Asia, where it appears that production of products from chloroform is on the rise. If chloroform emissions continue to increase, the researchers predict that the recovery of the ozone layer could be delayed by four to eight years.

“[Ozone recovery] is not as fast as people were hoping, and we show that chloroform is going to slow it down further,” says co-author Ronald Prinn, the TEPCO Professor of Atmospheric Science at MIT. “We’re getting these little side stories now that say, just a minute, species are rising that shouldn’t be rising. And certainly a conclusion here is that this needs to be looked at.”

Xuekun Fang, a senior postdoc in Prinn’s group, is the lead author of the paper, which includes researchers from South Korea, Japan, England, Australia, and California.

Short stay, big rise

Chloroform is among a class of compounds called “very short-lived substances” (VSLS), for their relatively brief stay in the atmosphere (about five months for chloroform). If the chemical were to linger, it would be more likely to get lofted into the stratosphere, where it would, like CFCs, decompose into ozone-destroying chlorine. But because it is generally assumed that chloroform and other VSLSs are unlikely to do any real damage to ozone, the Montreal Protocol does not stipulate regulating the compounds.

“But now that we’re at the stage where emissions of the more long-lived compounds are going down, the further recovery of the ozone layer can be slowed down by relatively small sources, such as very short-lived species — and there are a lot of them,” Prinn says.

Prinn, Fang, and their colleagues monitor such compounds, along with other trace gases, with the Advanced Global Atmospheric Gases Experiment (AGAGE) — a network of coastal and mountain stations around the world that has been continuously measuring the composition of the global atmosphere since 1978.

There are 13 active stations scattered around the world, including in California, Europe, Asia, and Australia. At each station, air inlets atop typically 30-foot-tall towers pull in air about 20 times per day, and researchers use automated instruments to analyze the atmospheric concentrations of more than 50 greenhouse and ozone-depleting gases. With stations around the world monitoring gases at such a high frequency, AGAGE provides a highly accurate way to identify which emissions might be rising and where these emissions may originate.

When Fang began looking through AGAGE data, he noticed an increasing trend in the concentrations of chloroform around the world between 2010 and 2015. He also observed about three times the amount of atmospheric chloroform in the Northern Hemisphere compared to the Southern Hemisphere, suggesting that the source of these emissions stemmed somewhere in the Northern Hemisphere.

Using an atmospheric model, Fang’s collaborators on the paper estimated that between 2000 and 2010, global chloroform emissions remained at about 270 kilotons per year. However, this number began climbing after 2010, reaching a high of 324 kilotons per year in 2015. Fang observed that most stations in the AGAGE network did not measure substantial increases in the magnitude of spikes in chloroform, indicating negligible emission rises in their respective regions, including Europe, Australia, and the western United States. However, two stations in East Asia — one in Hateruma, Japan, and the other in Gosan, South Korea — showed dramatic increases in the frequency and magnitude of spikes in the ozone-depleting gas.

The rise in global chloroform emissions seemed, then, to come from East Asia. To investigate further, the team used two different three-dimensional atmospheric models that simulate the movement of gases and chemicals, given global circulation patterns. Each model can essentially trace the origins of a certain parcel of air. Fang and his colleagues fed AGAGE data from 2010 to 2015 into the two models and found that they both agreed on chloroform’s source: East Asia.

“We conclude that eastern China can explain almost all the global increase,” Fang says. “We also found that the major chloroform production factories and industrialized areas in China are spatially correlated with the emissions hotspots. And some industrial reports show that chloroform use has increased, though we are not fully clear about the relationship between chloroform production and use, and the increase in chloroform emissions.”

“An unfortunate coherence”

Last year, researchers from the United Kingdom reported on the potential threat to the ozone layer from another very short-lived substance, dichloromethane, which, like chloroform, is used as a feedstock to produce other industrial chemicals. Those researchers estimated how both ozone and chlorine levels in the stratosphere would change with increasing levels of dichloromethane in the atmosphere.

Fang and his colleagues used similar methods to gauge the effect of increasing chloroform levels on ozone recovery. They found that if concentrations remained steady at 2015 levels, the increase observed from 2010 to 2015 would delay ozone recovery by about five months. If, however, concentrations were to continue climbing as they have through 2050, this would set a complete healing of the ozone layer back by four to eight years.

The fact that the rise in chloroform stems from East Asia adds further urgency to the situation. This region is especially susceptible to monsoons, typhoons, and other extreme storms that could give chloroform and other short-lived species a boost into the stratosphere, where they would eventually decompose into the chlorine that eats away at ozone.

“There’s an unfortunate coherence between where chloroform is being emitted and where there are frequent storms that puncture the top of the troposphere and go into the stratosphere,” Prinn says. “So, a bigger fraction of what’s released in East Asia gets into the stratosphere than in other parts of the world.”

Fang and Prinn say that the study is a “heads-up” to scientists and regulators that the journey toward repairing the ozone layer is not yet over.

“Our paper found that chloroform in the atmosphere is increasing, and we identified the regions of this emission increase and the potential impacts on future ozone recovery,” Fang says. “So future regulations may need to be made for these short-lived species.”

“Now is the time to do it, when it’s sort of the beginning of this trend,” Prinn adds. “Otherwise, you will get more and more of these factories built, which is what happened with CFCs, where more and more end uses were found beyond refrigerants. For chloroform, people will surely find additional uses for it.”

Source: Massachusetts Institute of Technology [December 20, 2018]



Genetic study reveals how citrus became the Med’s favorite squeeze

Genetic detective work has illuminated the important role of Jewish culture in the widespread adoption of citrus fruit by early Mediterranean societies.

Genetic study reveals how citrus became the Med's favorite squeeze
Buddha’s Hands – citron study highlights historic path of domestication
[Credit: Mathulack Photography]

The fascinating find came to light in an investigation into a bizarre acidless mutation which makes citrus juice 1000 times less acidic.

John Innes Centre researchers used genetic analysis to trace the acidless mutations in citron, the first citrus species to be cultivated in the Mediterranean.

“Some people thought that this was a recent mutation that originated in Corsica, or somewhere in the Mediterranean, but we have found that this is not new. It’s an ancient mutation that is present in Chinese fingered citrons known as Buddha’s Hands and those used in the Sukkot Jewish ritual,” explains Dr. Eugenio Butelli of the John Innes Centre and first author of the paper.

The acidless mutations have captivated botanists and breeders for centuries and appear in many citrus varieties including citron, sweet lime, limetta, lemon and sweet orange.

Acidless citrus fruit have also lost the ability to produce anthocyanin pigments, that give a blush of dark red to leaves, flowers and, sometimes, flesh.

The researchers identified a gene, which they called Noemi, as the key factor behind the regulation of fruit acidity. Analysis also revealed that this gene works in partnership with another, named Ruby, to control anthocyanin production.

The study identified specific mutations affecting the Noemi gene in several acidless citrus species and hybrids. These acidless fruits are often referred to as sweet or insipid because of the reduction in fruit acidity and are highly prized citrons (Etrog in Hebrew) used in the Jewish harvest festival of Sukkot.

One of these mutations matched those found in fingered citron varieties first cultivated in China 3300 years ago. This confirmed that this mutation originated before the arrival of citron into the Mediterranean.

Further analysis revealed that the same ancient Noemi allele characteristic of the acidless trait was present in the Yemen citron, an ancient variety traditionally used in the Sukkot tradition since the time of the destruction of the first temple in 587 B.C.E. Another variety traditionally used in the Sukkot ritual, the Greek citron, also bore the same genetic hallmark.

The analysis suggests that the authentic Jewish Etrog used ritually was an acidless one, an idea supported by a reference to “sweet citron” in the Jewish legal text, the Talmud, dating from 200 C.E.

The study which appears in Current Biology illuminates the path of domestication of citron. It supports the view that the spread of citron in Mediterranean regions was facilitated by its adoption in Jewish culture as an important religious symbol. Some scholars speculate that Jews in exile in Babylonia brought the citron back to Palestine.

Why was this sweet, or insipid citrus, with plain white flowers and leaves drained of colour, the chosen fruit?

“Citron was first cultivated for its medicinal properties in China and its rind was used as a medicinal product, not as a food” explains Professor Cathie Martin of the John Innes Centre and a co-author on the study.

“By the time it reached the Mediterranean in Roman times, citron was a luxury item used for its fragrance to keep linen fresh. The presence of white flowers in the acidless mutation seems important because they are a symbol of purity and we speculate that there was a strong selection for the loss of anthocyanins, which normally add colour to leaves and flowers.”

Citron is one of four primary species that make up the citrus genus, a complex group of flowering plants with notable nutritional, medicinal and aromatic value. Despite becoming one of the world’s most economically important fruit crops, its history of evolution and domestication has remained obscure until recently.

The characterisation of Noemi provides researchers with an important genetic marker opening a fascinating landscape for genetic analysis of seeds found amid the burials of the ancient world and fossil remains from even further back in time.

The study also gives researchers the information they need to develop fruit of the future—to modulate their level of acidity and to increase their content of health-protecting anthocyanin compounds.

“If you could introduce these mutations stably in lemon, for example, you could make lemonade which does not need so much added sugar in it, making it healthier to drink and better for growing teeth.” explains Professor Martin.

Source: John Innes Centre [December 20, 2018]



Spectacular flying reptiles soared over Britain’s tropical Jurassic past

Spectacular flying reptiles armed with long teeth and claws which once dominated the skies have been rediscovered, thanks a palaeontology student’s PhD research.

Spectacular flying reptiles soared over Britain's tropical Jurassic past
Well armed Klobiodon: Flying reptiles, including the newly discovered Klobiodon rochei,
have been put together from fragments found in fossil-rich Stonesfield, in Oxfordshire
[Credit: Mark Witton]

Dr Michael O’Sullivan, at the University of Portsmouth, has uncovered evidence of well armed and substantial flying reptiles from historically important, but overlooked, British Jurassic fossils.

He’s also found a new species of pterosaur with a wingspan of two metres – as large as a modern mute swan, and a giant in its time.

Some 200 fossils of flying reptiles – pterosaurs – have been collected over the last two centuries from the Stonesfield Slate, but their significance has been long neglected by palaeontologists, probably because they are mere fragments.

Closer inspection has revealed evidence of multiple pterosaur lineages in the UK’s Jurassic past, including some unexpectedly large and formidably armed species.

The research is published in Acta Palaeontologica Polonica where it is highlighted as ‘editor’s choice’.

Dr O’Sullivan, in the University’s School of Earth and Environmental Sciences, said: “It’s large fangs would have meshed together to form a toothy cage, from which little could escape once Klobiodon had gotten a hold of it.

“The excellent marine reptiles and ammonites of the UK’s Jurassic heritage are widely known, but we celebrate our Jurassic flying reptiles far less.

Spectacular flying reptiles soared over Britain's tropical Jurassic past
The first dinosaur ever found, the predatory Megalosaurus came from same location, in Oxfordshire
[Credit: Mark Witton]

“The Stonesfield pterosaurs are rarely pretty or spectacular, but they capture a time in flying reptile evolution which is poorly represented globally. They have an important role to play in not only understanding the UK’s natural history, but help us understand the bigger global picture as well.”

He has named the new species Klobiodon rochei. The generic name means ‘cage tooth’, in reference to its huge, fang-like teeth – up to 26mm long at a time when few pterosaurs had any teeth – and the species name honours comic book artist Nick Roche in recognition of the role popular media has in how extinct animals are portrayed.

Only the lower jaw of Klobiodon is known, but it has a unique dental configuration that allows it to be distinguished from other pterosaurs. It was likely a gull or tern-like creature – a coastal flier that caught fish and squid using its enormous teeth, swallowing them whole.

Much of Dr O’Sullivan’s research has involved untangling the messy science associated with these neglected specimens.

He said: “Klobiodon has been known to us for centuries, archived in a museum drawer and seen by dozens or hundreds of scientists, but it’s significance has been overlooked because it’s been confused with another species since the 1800s.”

Klobiodon and the other Stonesfield pterosaurs lived alongside one of the most famous and important dinosaurs in the world, the predatory Megalosaurus, the first dinosaur ever named. But as global sea levels were higher, and the world was much warmer, their Jurassic Britain was a series of large tropical islands.

Dr O’Sullivan was examining the Stonesfield pterosaur collections held in museums across the UK for his PhD studies when he found evidence of three distinct types of pterosaur, some of which are the oldest of their kind, as well as evidence of a new pterosaur species.

Stonesfield Slate, where the new pterosaur fossils were found, is a rich source of Jurassic fossils about 10 miles northwest of Oxford. It is where, in 1824, Britain’s first discovered dinosaur, the Megalosaurus, was found.

The quantity and quality of such fossils from the area might be why these fragments have until now been overlooked.

Source: University of Portsmouth [December 20, 2018]



Newborn insects trapped in amber show first evidence of how to crack an egg

Fossilised newborns, egg shells, and egg bursters preserved together in amber provide the first direct evidence of how insects hatched in deep time, according to a new article published in the journal Palaeontology.

Newborn insects trapped in amber show first evidence of how to crack an egg
Four complete Tragychrysa ovoruptora newborns preserved together with egg shell remains
and one visible egg burster (right inset) [Credit: Palaeontology, 2018]

One of the earliest and toughest trials that all organisms face is birth. The new findings give scientists evidence on how tiny insects broke the barrier separating them from life and took their first steps into an ancient forest.

Trapped together inside 130 million-year-old Lebanese amber, or fossilised resin, researchers found several green lacewing newborn larvae, the split egg shells from where they hatched, and the minute structures the hatchlings used to crack the egg, known as egg bursters. The discovery is remarkable because no definitive evidence of these specialised structures had been reported from the fossil record of egg-laying animals, until now.

The fossil newborns have been described as the new species Tragichrysa ovoruptora, meaning ‘egg breaking’ and ‘tragic green lacewing’, after the fact that multiple specimens were ensnared and entombed in the resin simultaneously.

“Egg-laying animals such as many arthropods and vertebrates use egg bursters to break the egg surface during hatching; a famous example is the ‘egg tooth’ on the beak of newborn chicks,” explains Dr Ricardo Pérez-de la Fuente, a researcher at Oxford University Museum of Natural History and lead author of the work. “Egg bursters are diverse in shape and location. Modern green lacewing hatchlings split the egg with a ‘mask’ bearing a jagged blade. Once used, this ‘mask’ is shed and left attached to the empty egg shell, which is exactly what we found in the amber together with the newborns.”

Newborn insects trapped in amber show first evidence of how to crack an egg
Studied amber preparations (top) and extant green lacewing egg batch (bottom) for comparison. Note the pinhead
for scale [Credit: Ricardo Pérez-de la Fuente, Oxford University Museum of Natural History]

Green lacewing larvae are small hunters which often carry debris as camouflage, and use sickle-shaped jaws to pierce and suck the fluids of their prey. Although the larvae trapped in amber differ significantly from modern-day relatives, in that they possess long tubes instead of clubs or bumps for holding debris, the studied egg shells and egg bursters are remarkably similar to those of today’s green lacewings. Altogether, they provide the full picture of how these fossil insects hatched like their extant counterparts, about 130 million years ago during the Early Cretaceous.

“The process of hatching is ephemeral and the structures that make it possible tend to disappear quickly once egg-laying animals hatch, so obtaining fossil evidence of them is truly exceptional,” remarks Dr Michael S. Engel, a co-author of the study from the University of Kansas.

The Tragichrysa ovoruptora larvae were almost certainly trapped by resin while clutching the eggs from which they had freshly emerged. Such behaviour is common among modern relatives while their body hardens and their predatory jaws become functional. The two mouthparts forming the jaws are not interlocked in most of the fossil larvae, which further suggests that they were recently born.

All the preparations studied were obtained from the same amber piece and are as thin as a pinhead, allowing a detailed account of the fossils and finding the tiny egg bursters, according to Dr Dany Azar, another co-author of the work, from the Lebanese University, who discovered and prepared the studied amber samples.

Newborn insects trapped in amber show first evidence of how to crack an egg
Reconstruction of two Tragychrysa ovoruptora newborns clutching the eggs from where they recently hatched,
moments before they were trapped by resin. Larvae color and egg stalks are conjectural
[Credit: Palaeontology, 2018]

It would seem reasonable to assume that traits controlling a life event as crucial as hatching would have remained quite stable during evolution. However, as Dr Enrique Peñalver of the Spanish Geological Survey (IGME; Geomining Museum) and co-author of the work explains: “There are known instances in modern insects where closely related groups, even down to the species level, show different means of hatching that can entail the loss of egg bursters. So, the long-term stability of a hatching mechanism in a given animal lineage cannot be taken for granted.”

Nonetheless, this new discovery in fossil green lacewings shows the existence 130 million years ago of a sophisticated hatching mechanism which endures to this day.

Source: University of Oxford [December 20, 2018]



The idiosyncratic mammalian diversification after extinction of the dinosaurs

Mass extinction typically conjures up a picture of a meteor falling to Earth and decimating the dinosaurs along with everything else. However, this is not exactly what happened. Different groups of living beings were affected differently by the various mass extinctions that have occurred during the planet’s history.

The idiosyncratic mammalian diversification after extinction of the dinosaurs
Origination, extinction and diversification rates for the three mammalian clades in North America.
Dotted lines denote the Cretaceous-Paleogene boundary [Credit: Biology Letters, 2018]

Consider mammals, a class of vertebrates that already existed during the dinosaur era and survived the mass extinction event in which almost all the dinosaurs were wiped out 66 million years ago, marking the end of the Cretaceous Period.

Four lineages of mammals were contemporaries of the giant reptiles. All four survived. Some were worse hit than others. In a study published in the journal Biology Letters, biologists Tiago Bosisio Quental of the University of São Paulo (USP) and Mathias Pires of the University of Campinas (UNICAMP), both from Brazil, set out to understand how the different groups of mammals made it through the end-Cretaceous mass extinction. Their research was supported by São Paulo Research Foundation – FAPESP.

“When people talk about a mass extinction, it’s assumed that they’re referring to a single extinction event of exceptional magnitude during which a large number of species became extinct in a relatively short time,” Pires said.

Another way of looking at mass extinctions consists of observing the number of species in the fossil record. It can be inferred that a mass extinction occurred in a given geological period when the total number of species that disappeared from the fossil record was much higher than the number of new species that emerged.

“In other words, the extinction rate – the speed at which species are lost – surpasses the speciation rate – the speed at which species are created. This makes the diversification rate negative, since the diversification rate is given by the difference between the extinction and speciation rates,” Pires said.

Five great mass extinctions have been identified in the fossil record in the last 500 million years (as well as many others on a smaller scale). They occurred for various reasons, such as magma spills lasting thousands or millions of years and releasing billions of tons of greenhouse gases that poisoned the atmosphere and blocked out the sun’s rays.

This is what caused the worst of all mass extinctions, in which over 90% of species vanished. It happened 252 million years ago, marking the boundary between the Permian and Triassic Periods (and between the Paleozoic and Mesozoic Eras).

Mass extinctions have also been caused by huge greenhouse effects due to the release of billions of tons of carbon gas (CO2) trapped under the seabed. One such episode is believed to have occurred at the end of the Triassic some 201 million years ago, killing 80% of all species.

The reverse has also happened, with billions of tons of CO2 being sequestered from the atmosphere and causing temperatures to crash and ice to cover the planet. This was the case 444 million years ago at the end of the Ordovician, when 86% of life forms disappeared.

The mass extinction that occurred 66 million years ago is known as the K-Pg event. The acronym refers to the end of the Cretaceous (Kreide in German) and the onset of the Paleogene (Pg).

On a larger time scale, the K-Pg event marks the boundary between the Mesozoic, the era dominated by dinosaurs, and the Cenozoic, the era extending from 66 million years ago to the present day during which mammals have been one of the dominant groups on the planet.

The K-Pg event was caused by a combination of two factors: devastating magma spills in what is now India and the impact of a comet or asteroid with a diameter of 10 km on the Yucatán peninsula in Mexico.

“All these mass extinction episodes are heterogeneous. They occurred for different reasons and unfolded in different ways. Their impact on life forms was not absolute but relative. Some groups suffered more, others less. Some disappeared, while others took advantage of the new environmental conditions after the catastrophe to diversify rapidly,” Pires said.

In the new study that was supported by FAPESP, the researchers set out to investigate how the different lineages of mammals that existed at the end of the Cretaceous succeeded in emerging from the biotic bottleneck represented by the K-Pg event. Daniele Silvestro of the University of Gothenburg (Sweden) and Brian Rankin of the University of California Berkeley (USA) also participated in the study.

The great class of mammals emerged in the Triassic at least 220 million years ago. This is the age of the oldest known fossil. At the end of the Cretaceous, mammalian species were highly diversified. There were the Eutheria or placental mammals, the clade to which Homo sapiens belongs, as do all primates, rodents, bats, cetaceans, and ungulates, among others.

In addition, there were Metatheria or marsupials, the clade to which today’s opossums, kangaroos, and koalas belong. They shared the planet with monotremes (egg-laying mammals) and multituberculates (an extinct taxon of rodent-like mammals named for the specific shape of their teeth, which had multiple tubercles).

The study by Pires and Quental stresses that mammals were particularly hard hit by the mass extinction in the Cretaceous. This does not mean that all four groups suffered equally. The mass extinction was more severe for some than for others.

During the Cretaceous, between 145 million and 66 million years ago, the multituberculates were the dominant and most diversified group of mammals. We know this because multituberculates are the vast majority in the fossil record prior to the K-Pg event. Fossils of placentals and marsupials are less numerous but also plentiful.

Monotremes are the exception. Today, they are few and far between. Indeed, they are comprised of just two families: one includes the duck-billed platypus while the other regards echidnas. Monotremes are also rare in the fossil record both before and after the Cretaceous, suggesting that the group has always been relatively marginal among mammals. For this reason, the researchers did not include monotremes in their study.

Given the knowledge that there were multituberculates, placentals, and marsupials, which group of mammals was most severely affected by the K-Pg event? Which had the most surviving genera? Which displayed the largest increase in diversity (or highest speciation rate) in the millions of years that followed the biotic bottleneck? Which group failed to recover from the cataclysm?

The only way to find answers to these questions is by analyzing the fossil record in a specific region of the planet to try to ensure that all groups of mammals were affected more or less to the same extent by the catastrophe 66 million years ago and in that region.

Quental and Pires chose North America as the focus for their study. One hundred and fifty years of continuous paleontological prospecting in the region have created a detailed picture of mammalian diversity before, during and after the K-Pg event.

“North America has a fossil record of sufficient quality for this kind of study. Other studies have been conducted to analyze how mammals as a whole survived the Cretaceous extinction, but as far we know, this is one of the first studies to analyze the dynamics of diversification in the different groups of mammals,” Quental said.

Distinct diversification patterns

The scientists used a dataset containing 188 recent fossil assemblages from the Cretaceous and Paleocene (spanning from 69.9 million to 55 million years ago) located in the western interior of North America.

“The North American mammal fossil record has the richest and most extensively studied assemblages near the K-Pg event. Fossil occurrences are relatively well resolved, minimizing taxonomic uncertainty. This dataset includes information on nearly 290 genera of mammals, including multituberculates, eutherians, and metatherians,” Quental said.

Several advanced statistical methods were used to estimate origination, extinction and diversification patterns before, during and after the K-Pg event. The results showed that the three groups emerged very differently from the mass extinction.

The origination rate for Methateria (marsupials), for example, remained approximately constant throughout the studied interval. However, a clear peak in extinction was identified during the K-Pg, generating a pulse of negative net diversification. After the K-Pg, the extinction rate gradually diminished, but negative net diversification persisted for more than 2 million years until approximately 64 million years ago.

Multituberculates were diversifying toward the end of the Cretaceous prior to the K-Pg boundary, showing high origination rates and relatively low extinction rates. Near the K-Pg boundary, the extinction rate remained low, but a drop in origination reduced the diversification of multituberculates to near zero. In other words, during the K-Pg, the diversification rate was in balance, as roughly the same number of genera were being created and becoming extinct.

According to the study, after the K-Pg boundary, the extinction rate for multituberculates continued to fall; however, the decrease in multituberculates’ origination rate was even sharper, hence leading to negative diversification. Thus, the number of genera continued to diminish throughout the rest of the period analyzed, until 55 million years ago. The decline appears to have persisted for a long time, given that the multituberculates steadily disappear from the world fossil record. The clade ends approximately 35 million years ago.

Scientists believe the reason for the disappearance of the multituberculates may have been growing competition with rodents, a new eutherian lineage that originated shortly after the K-Pg in the Paleogene.

Eutherians (placentals) display high origination and high extinction near the K-Pg, resulting in high diversity turnover. Originations were higher than extinctions, except between 66 million and 64 million years ago.

Not long after this, there was a second origination pulse accompanied by a drop in the extinction rate, evidencing a short burst in diversification. Around 62 million years ago origination decreased and diversification remained around zero, suggesting diversity equilibrium.

“We found three diversification patterns among the mammalian groups. Metatheria (marsupials) conformed to the classic mass extinction response, with several temporally clustered extinctions leading to a sharp drop in diversification,” Quental said.

Multituberculates underwent a reduction in diversity, with a decrease in diversification and subsequent diversity loss driven by declining origination rates rather than extinction. In other words, their diversity diminished because the creation of new species took a long time.

“Among eutherians there was a more complex rise-and-fall pattern due to rapid fluctuations in the speciation rate during and just after the K-Pg, while the extinction rate rose but not enough to cause negative diversification for long,” Quental said.

According to Pires, the study shows that the K-Pg mass extinction was ecologically selective among mammalian lineages. “Extinctions were concentrated among the specialized carnivorous metatherians and insectivorous eutherians, whereas more generalized eutherians and multituberculates survived and maintained higher diversity,” he said.

Although the results suggest eutherians suffered substantial losses at the K-Pg boundary, these losses were offset by increased origination. Diversification may have occurred among the survivors as other groups of eutherians came to North America from other continents.

“The dietary plasticity of multituberculates may have enabled some species to persist, explaining the low extinction rates. The ecological and taxonomic diversity of multituberculates increased during the late Cretaceous. However, our analysis shows that the multituberculates failed to offset extinction losses because they created less and less diversity, unlike the eutherians, whose losses were offset by high origination rates,” Pires said.

In their conclusion, the authors note that when clades are assessed individually, mass extinction events may be seen as shifts in extinction, in origination, or in both regimes.

“This means that studies of macroevolutionary phenomena focusing on broad taxonomic groups may miss a much richer macroevolutionary history, which can be perceived only at finer taxonomic scales,” Pires said.

Author: Peter Moon | Source: FAPESP [December 20, 2018]



Fur trade may have spread the plague through Europe

A new ancient DNA study shows that 14th century plague outbreaks might have resulted from repeated introductions of Yersinia pestis to Europe. Commercial trade routes, including the fur trade routes, would have contributed to the rapid spread of plague in whole Europe during the Middle Ages.

Fur trade may have spread the plague through Europe
Around 30 per cent of the European population died from plague between 1347 and 1353.
Illustration by Pieart dou Tielt [Credit: WikiCommons]

The bacterium Yersinia pestis is the causative agent of bubonic and pulmonary plague in humans. Plague is primarily a disease of wildlife and is maintained in reservoirs, which nowadays are present on all continents with the exception of Australia and Western Europe.

Without doubt, the Black Death, which marks the arrival of Y. pestis into Europe in 1347, represents one of the most significant events that marked the beginning of the second plague pandemic during the medieval period. In fact, from 1347 to 1353, plague spread through whole Europe like wildfire, leading to the decline of the European population by 30 %. After this dramatic period and for more than 350 years, Europe knew a series of recurrent devastating outbreaks of Y. pestis.

Understanding the plague

During the last decades, different studies tried to understand the origin of these outbreaks. Two hypotheses emerged from these studies. According to the first hypothesis, after a first introduction during the Black Death, one or more reservoirs of Y. pestis were established in Western Europe – which explains these recurrent outbreaks.

“The other hypothesis suggest that the plague was repeatedly introduced to Western Europe from a reservoir located in Eastern Europe/Central Asia and spread via commercial trade routes and human movement”, explains Professor Nils Chr. Stenseth. He was the leader of the Centre for Ecological and Evolutionary Synthesis (CEES) at the University of Oslo for more than 10 years, and is now a strategic advisor at the UiO’s Faculty of Mathematics and Natural Sciences.

In a new paper from the CEES, published in Proceedings of the National Academy of Sciences, these two scenarios are investigated using five newly presented ancient genomes (aDNA) of Y. pestis  isolated from skeletons distributed in archaeological sites from South (Abbadia San Salvatore, Italy and Saint-Laurent-de-la-Cabrerisse, France) to North Europe (Bergen-op-Zoom in the Netherlands and Oslo, Norway). The ancient genomes from Abbadia San Salvatore and Oslo are the first ancient DNA sequences reported from Italy and Norway.

Fur trade may have spread the plague through Europe
The fur trade from the East towards Western Europa followed two major routes during the Middle Ages
[Credit: Amine Namouchi]

The Second Pandemic

Contrary to previous studies, the authors built an integrative approach aiming at interpreting all ancient genomes of the Second plague Pandemic with regards to their historical context. A total number of 126 Y. pestis strains and fifteen ancient genomes were analysed in this study. Five out of the eleven ancient DNA samples dated to the Second Plague Pandemic were part of the first wave of introduction of Y. pestis into Europe during the Black Death.

These ancient DNA samples were isolated from the cities of Abbadia San Salvatore (Italy), Saint-Laurent-de-la-Cabrairisse (France), Barcelona (Spain), London (United Kingdom) and Oslo (Norway). Intriguingly, all these ancient genomes were identical except the one isolated from Abbadia San Salvatore, for which the authors found two extra point mutations.

Historical data investigation of contacts and bed testaments conducted by the authors revealed the high percentage of people killed by plague within four months from late June to early September 1348 in Abbadia San Salvatore. CEES researcher Amine Namouchi and colleagues advance in their paper that these two additional point mutations were acquired through a large transmission chain in Italy, rather than having been gained within a newly established local wildlife reservoir. Regarding the aDNA found in Oslo, the authors found that it is most likely dated to 1348. This is in line with historical, archaeological and radiocarbon dating data described in their paper.

A new hypothesis

While the origin of the Black Death remains unclear, in their PNAS paper, the authors advance a new hypothesis that relates the onset of the Black Death with the arrival of a considerable variety of fur in the ports of the Black Sea by 1340 from trade routes starting from Sarai.

In fact, during the same period a new mainland route connecting Sarai, Tana and Caffa had been established with the support of the Golden Horde, observes Amine Namouchi and colleagues. The Golden Horde was originally a Mongol and later Turkicized khanate established in the 13th century and originating as the northwestern sector of the Mongol Empire. The Crimean Khanate and the Kazakh Khanate, the last remnants of the Golden Horde, survived until 1783 and 1847 respectively.

Fur trade may have spread the plague through Europe
The Norwegian artist Theodor Kittelsen (1857-1914) pictured the Black Death as an old woman
travelling from farm to farm in rural Norway, bringing death and destruction with her.
Here she is coming up the stairs [Credit: WikiCommons]

Just after the Black Death period, the authors confirm the so-called pestis secunda that occured from 1357 to 1366.

“The group of aDNA that belongs to the pestis secunda includes samples from London, Bolgar-City (Russia) and the newly presented two aDNA from Bergen-op-Zoom. Four point mutations separate the group of aDNA of the Black Death from the group that belongs to the pestis secunda. Corroborated with historical data, we  claim that the pestis secunda might also be the result of the introduction of Y. pestis along the fur trade routes established between Novgorod (Russia) and Western Europe through the Hanseatic League”, adds Namouchi.

Multiple waves of introduction

Overall, in this new paper published in PNAS, by describing all previously and newly described aDNA of Y. pestis in their historical context, Namouchi and colleagues provided additional evidence that the recurrent plague outbreaks during the Second plague Pandemic were the result of multiple waves of introduction of Y. pestis from a reservoir located in Eastern Europe/Central Asia.

This result is in line with previous studies based on Ecological evidence. Commercial trade routes, including the fur trade route, as-well-as human movement would have contributed to the rapid spread of plague in whole Europe during the Middle Ages.

The investigation behind the new scientific paper was done in the context of the research project MedPlag, led by the paleogenetist and CEES researcher Barbara Bramanti. In 2013, she received an Advanced Grant from the European Research Council (ERC). The grant is being used to investigate, using DNA technology, the plague and other potential human diseases caused by medieval microbes.

Author: Bjarne Røsjø | Source: University of Oslo [December 20, 2018]



Traces of possible pre-Roman theatre discovered in Pompeii

Pompeii may have had a theatre already at the time of the arrival of the Samnites in the fourth century BC, Superintendent Massimo Osanna said Thursday after the discovery of a concave area next to the second-century BC theatre that was preserved by the 79 AD eruption of Vesuvius. The new digs at the famed archaeological site have “raised this hypothesis”, he said.

Traces of possible pre-Roman theatre discovered in Pompeii
Credit: ANSA

There are archaeological remains in Pompeii for Greeks, Etruscans, Samnites, and an unnamed indigenous Italic population in addition to the Romans. The foundation of the city, and the exact phases of each cultural group, are a bit murky but are believed to date back to the sixth century BC.

It is however clear from the archaeological record in Pompeii and in other towns of southern Italy that sometime in the fourth century BC the people of Samnium moved down from the mountains and into some of the more urban areas. Just in Campania, there is evidence of Samnite populations in Capua and Nola in addition to Pompeii.

The tomb of a Samnite woman was found in Pompeii three years ago, while a recent dig uncovered a Samnite temple.

Archaeologists said the temple dated to the third century BC and was probably devoted to Mefitis, a Samnite version of Venus worshipped in volcanic areas and swamps. She was the personification of the poisonous vapours of the earth.

Traces of possible pre-Roman theatre discovered in Pompeii
Credit: ANSA

The Samnites, an Oscan-speaking people who once humiliated the Romans, were a tribe which controlled much of Italy south of Rome before the fourth century BC.

They fought three losing wars with Rome for the control of the region around Naples and later helped Rome’s great Carthaginian enemy Hannibal before finally being crushed in 82 BC.

The discovery of the temple revolutionized archaeologists’ concepts of the Samnites, showing them to be far more advanced than previously thought.

Samnites had largely been considered mountain warriors, whose settlements thrived due to a military pact with Rome.

But the temple dedicated to the swamp goddess showed that the Samnite culture was more sophisticated than realized.

Traces of possible pre-Roman theatre discovered in Pompeii
Credit: ANSA

The name Samnite comes by way of Greek and alludes to the point of a javelin. It suited the warlike tribesmen who fought a series of wars with the Romans and even defeated them soundly in the Battle of the Caudine Forks in 321 B.C., but who were eventually beaten back into their Apennine fastness, only to be absorbed by the Roman State.

A large amount of votive material was found at the temple site including lamps, terra cotta work, sea shells, coins and various kinds of bones.

Next to the temple archaeologists found the ruins of baths which may have been used for so-called “sacred prostitution,” in which betrothed maiden were given a coin before losing their virginity in the temple prior to marriage.

Archaeologists said the find provided further evidence that Pompeii was a full-fledged city before it was taken over by the Romans.

Emmanuele Curti of London’s Birkbeck College said the find was “of enormous interest” in a key area of the city between the Roman Forum and port.

Source: ANSA [December 21, 2018]



2018 excavations of Bronze Age settlement at Kissonerga-Skalia completed

The 2018 season of archaeological excavations at the Bronze Age settlement of Kissonerga-Skalia near Paphos, under the direction of Dr Lindy Crewe (Director, Cyprus American Archaeological Research Institute), has been completed. The site demonstrates a long Bronze Age sequence, and earlier Chalcolithic occupation, beginning before 2,500 BC and connected with the neighbouring Neolithic–Philia phase settlement of Kissonerga-Mosphilia. The site was abandoned around 1600 BC, during the transition to the Late Cypriot Bronze Age.

2018 excavations of Bronze Age settlement at Kissonerga-Skalia completed
Figure 1: Area P/B2 showing location of ashy area (upper right) and ground stone installations and post hole
(lower left). The position of Red Polished IV bowl (KS651) prior to removal is shown in the red circle
[Credit: Department of Antiquities, Republic of Cyprus]

During the final occupation phase a complex including some roofed areas and large open spaces was constructed. The complex has no evidence for domestic occupation and activities seem to be industrial, including large fire-related installations and the previously published malting kiln likely used in beer production. During the 2018 season the team further exposed the initial floor construction associated with the primary building phase.

As in previous years, this is usually constructed from extremely compacted mud plaster or plaster. The majority of features and emplacements are associated with the primary construction phase and during a second later phase some of these were deliberately floored over. It is likely that we are seeing a decline in the site, with a decrease in activities and perhaps a slow abandonment. This is further suggested by the number of mended pottery vessels found on the final floors, perhaps indicating that there were no potters remaining in the last years of occupation.

In the northern areas two walls run approximately parallel and form a contained space. On the interior faces of both walls wall tumble and collapse has been investigated, suggesting that this area may have been roofed and as the roof collapsed both walls were drawn inwards. This collapse was further investigated in 2018, exposing a further area of working space with large stone grinders and a stone platform for supporting a post or a vessel.

Figure 1 shows this area in the centre lower left of the photograph. Associated with this arrangement was a large Red Polished IV spouted bowl which had been deliberately smashed in place and a piece of the base removed (Figure 2), presumably to collect and drain a material ground with one of the stone grinders.

2018 excavations of Bronze Age settlement at Kissonerga-Skalia completed
Figure 2: Red Polished IV spouted bowl (KS651). The bowl was smashed in place and a fragment deliberately
removed during the Bronze Age. The handle was already missing when the bowl was deposited
[Credit: Department of Antiquities, Republic of Cyprus]

Excavations continued southwards to establish whether there was an interior space to the west of the courtyard previously associated with beer production. This bounded space in B2 forms a parallelogram rather than a rectangular space and with interior benches, made with a base of small stones and an upper packing of mud brick or mud plaster. To the south of the room it has been revealed that the malting kiln is now located at the centre of an L-shaped courtyard.
In the north of the plot the Bronze Age deposits had been completely truncated during agricultural activity that took place in the 1970’s, exposing earlier Chalcolithic levels and revealing four Chalcolithic pit graves cut into a trampled occupation surface. As burials at neighbouring Kissonerga-Mosphilia, were previously thought to be entirely within the settlement, this is important for understanding wider Chalcolithic burial practices and it appears we have a dedicated burial area. The team’s physical anthropologist, Dr Michelle Gamble, reports that the latest burial excavated contains the remains of a single adult female, lying on her right side. No grave goods were present in any of the burials in this area and all burials have been identified as females or children.

The Final Phase Complex now encompasses an area of 1200m2. The areas excavated all have evidence for large-scale cooking/heating or processing working areas and we have yet to establish a possible purpose for the large open spaces. Kissonerga-Skalia is an example of a phenomenon that occurs at the transition to the Late Bronze Age where people began to build big and produce goods at a greater scale. As the site was abandoned shortly after the complex was built and the remains are not obscured by later human activity we are able to examine this phenomenon in detail.

Source: Department of Antiquities, Republic of Cyprus [December 21, 2018]



Zahi Hawass calls for return of Nefertiti bust from Germany

Egyptologist and former Antiquities Minister Zahi Hawass called for the return of a bust of Nefertiti from Germany to Egypt, during his lecture in the Brazilian city of Sao Paulo, organized by the Egyptian Embassy in Brazil.

Zahi Hawass calls for return of Nefertiti bust from Germany
The stunning artefact has garnered huge popularity in Germany and has been famously
nicknamed The Lady of Berlin [Credit: Cairo Scene]

“Nefertiti’s head came out of [Egypt] illegally, and I call for its return to be seen by Egyptians at the inauguration of the Great Egyptian Museum,” he said.

Nefertiti’s story dates back to 1912, when a German archeological mission headed by Egyptologist Ludwig Borchardt visited Cairo and signed a contract with the Egyptian government, giving it the right to acquire some of the artifacts found in the area of Tell el-Amarna, which was built by Akhenaten, and became the capital instead of Thebes. Among the artifacts transferred by the mission outside Egypt was Nefertiti’s head.

The Nefertiti bust became a cultural symbol of Berlin, and sparked a heated debate between Egypt and Germany over Egypt’s request to return it among smuggled artifacts, according to Youm7.

Nefertiti lived in the 14th century BC, and was the wife of the Egyptian Pharaoh Akhenaten, one of the kings of the 18th Dynasty in ancient Egypt who ruled Egypt from 1352 BC to 1336 BC. Together, they heralded a religious revolution, based on the worship of the sun, or “Aton”.

Zahi Hawass calls for return of Nefertiti bust from Germany
Excavator Ludwig Borchardt (far left) brought Nefertiti to Berlin after her discovery in 1912,
 but there are questions about whether he used fraudulent measures to do so
[Credit: Universitätsarchiv Freiburg/Nachlass Prinz Johann Georg]

From the unveiling of the statue at the Berlin Museum in 1925 to this day, there has been widespread debate about the restoration of the statue.

In 1925, the Egyptian government declared a ban on German missions, until the head of the Pharaonic queen was returned to Egypt. During the reign of Adolf Hitler, he rejected any plan to return the bust to Egypt.

Some European countries, including Germany, have passed a law that considered any artifact that has been admitted on its territories for 25 years a national treasure, which formed a political and legal crisis regarding the Nefertiti statue.

Hawass argued that the Nefertiti statue was illegally exported from Egypt and should therefore be returned. He called in 2005 on Germany to prove that it legally obtained the statue.

Source: Al Bawaba [December 21, 2018]




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