суббота, 25 января 2020 г.

Mushrooms are older than thought

The origin and evolution of the kingdom Fungi--more commonly known as mushrooms--are still very mysterious. Only 2% of species in this kingdom have been identified, and their delicate nature means fossils are extremely rare and difficult to tell apart from other microorganisms. Until now, the oldest confirmed mushroom fossil was 460 million years old.

Mushrooms are older than thought
Fossilized network of filaments where vestiges of chitin - a very tough compound found in the cell
walls of fungi - was detected [Credit: Steeve Bonneville/Universite Libre de Bruxelles]
A group of researchers led by Professor Steeve Bonneville, from the 'Biogeochemistry and Earth system modelling' research unit (Faculty of Sciences) at the Universite libre de Bruxelles, has discovered a new mushroom fossil--the oldest to ever be identified from its molecular composition. Published in Science Advances, the study was conducted with help from several groups at ULB (Centre for Microscopy and Molecular Imaging and 4MAT), in close collaboration with Professor Liane Benning from the German Research Centre for Geoscience (GFZ Potsdam) and with support from other institutions abroad, including the UK's synchrotron (Diamond Light Source) and the Carnegie Institution for Science (Washington).

The fossilized remains of mycelium (a network of interconnected microscopic strands) were discovered in rocks whose age is between 715 and 810 million years--a time in Earth's history when life on the continents' surface was in its very infancy. These ancient rocks, found in the Democratic Republic of the Congo and part of the collection of the Africa Museum on Tervuren, formed in a lagoon or coastal lake environment. 'The presence of fungi in this transitional area between water and land leads us to believe that these microscopic mushrooms were important partners of the first plants that colonized the Earth's surface around 500 million years ago', explains Steeve Bonneville, professor at the Universite libre de Bruxelles and coordinator of the study.

Previous mushroom fossils had been identified only based on the morphology of organic remains extracted from rocks using corrosive acid compounds. 'This method damages the chemistry of organic fossils and only allows morphological analysis, which can lead to incorrect interpretations because certain morphological characteristics are common to different branches of living organisms', Steeve Bonneville says.

This is why the authors of this new study used multiple molecular analysis techniques at a microscopic scale: synchrotron radiation spectroscopy (XANES, μFTIR), μ-Raman confocal microscopy, fluorescence microscopy (CLSM) and electron microscopy (FIB-TEM-HAADF). Using these techniques, it was possible to study the chemistry of organic remains in situ, without chemical treatment. This enabled the researchers to detect traces of chitin, a very tough compound found in the cell walls of fungi. They also demonstrated that the organisms were eukaryotes, i.e. their cells had a nucleus. "Only by cross- correlating chemical and micro-spectroscopic analyses could we demonstrate that the structures found in the old rock are indeed ~ 800-million-year-old fungal remains", reacts Liane Benning from GFZ Potsdam.

'This is a major discovery, and one that prompts us to reconsider our timeline of the evolution of organisms on Earth', concludes Steeve Bonneville. 'The next step will be to look further back in time, in even more ancient rocks, for evidence of those microorganisms that are truly at the origins of the animal kingdom.'

Source: Universite libre de Bruxelles [January 22, 2020]

* This article was originally published here

3,000-year-old teeth solve Pacific banana mystery

Humans began transporting and growing banana in Vanuatu 3000 years ago, a University of Otago scientist has discovered.

3,000-year-old teeth solve Pacific banana mystery
Skeletons found at a 3,000-year-old Teouma cemetery, just outside the capital of Port Vila in Vanuatu
[Credit: Frederique Valentin]
The discovery is the earliest evidence of humans taking and cultivating banana in to what was the last area of the planet to be colonised.

In an article published this week in Nature Human Behaviour, Dr Monica Tromp, Senior Laboratory Analyst at the University of Otago's Southern Pacific Archaeological Research (SPAR), found microscopic particles of banana and other plants trapped in calcified dental plaque of the first settlers of Vanuatu. The finds came from 3000-year-old skeletons at the Teouma site on Vanuatu's Efate Island.

Dr Tromp used microscopy to look for 'microparticles' in the plaque, also known as dental calculus, scraped from the teeth of the skeletons. That allowed her to discover some of the plants people were eating and using to make materials like fabric and rope in the area when it was first colonised.

Teouma is the oldest archaeological cemetery in Remote Oceania, a region that includes Vanuatu and all of the Pacific islands east and south, including Hawaii, Rapa Nui and Aotearoa. The Teouma cemetery is unique because it is uncommon to find such well-preserved archaeological burials in the Pacific. Bone generally does not preserve in hot and humid climates and the same is true for things made of plant materials and also food.

The first inhabitants of Vanuatu were people associated with the Lapita cultural complex who originated in Island South East Asia and sailed into the Pacific on canoes, reaching the previously uninhabited islands of Vanuatu around 3000 years ago.

3,000-year-old teeth solve Pacific banana mystery
The findings were made from 3,000-year-old skeletons at Teouma, the oldest archaeological cemetery in Remote Oceania,
a region that includes Vanuatu and all of the Pacific Islands east and South, including Hawaii, Rapa Nui
and Aotearoa [Credit: University of Otago]
There has been debate about how the earliest Lapita people survived when they first arrived to settle Vanuatu and other previously untouched islands in the Pacific. It is thought Lapita people brought domesticated plants and animals with them on canoes - a transported landscape. But direct evidence for these plants had not been found at Teouma until Dr Tromp's study.

"One of the big advantages of studying calcified plaque or dental calculus is that you can find out a lot about otherwise invisible parts of people's lives," Dr Tromp says. Plaque calcifies very quickly and can trap just about anything you put inside of your mouth - much like the infamous Jurassic Park mosquito in amber - but they are incredibly small things that you can only see with a microscope."

The study began as part of Dr Tromp's PhD research in the Department of Anatomy and involved collaboration with the Vanuatu Cultural Centre, Vanuatu National Herbarium and the community of Eratap village - the traditional landowners of the Teouma site.

Dr Tromp spent hundreds of hours in front of a microscope finding and identifying microparticles extracted from thirty-two of the Teouma individuals. The positive identification of banana (Musa sp.) is direct proof it was brought with the earliest Lapita populations to Vanuatu.

Palm species (Arecaceae) and non-diagnostic tree and shrub microparticles were also identified, indicating these plants were also important to the lives of this early population, possibly for use as food or food wrapping, fabric and rope making, or for medicinal purposes, Dr Tromp says.

"The wide, and often unexpected range of things you can find in calcified plaque makes what I do both incredibly exciting and frustrating at the same time."

Source: University of Otago [January 22, 2020]

* This article was originally published here

Study reveals two writers penned landmark inscriptions in 8th-century BCE Samaria

The ancient Samaria ostraca -- eighth-century BCE ink-on-clay inscriptions unearthed at the beginning of the 20th century in Samaria, the capital of the biblical kingdom of Israel -- are among the earliest collections of ancient Hebrew writings ever discovered. But despite a century of research, major aspects of the ostraca remain in dispute, including their precise geographical origins -- either Samaria or its outlying villages -- and the number of scribes involved in their composition.

Study reveals two writers penned landmark inscriptions in 8th-century BCE Samaria
Ostraca (ink on clay inscriptions) from Samaria, the capital of biblical Israel. The inscriptions are dated to the
 early 8th century BCE. Colorized Ostraca images are courtesy of the Semitic Museum, Harvard University
[Credit: American Friends of Tel Aviv University/Semitic Museum, Harvard University]
A new Tel Aviv University (TAU) study finds that just two writers were involved in composing 31 of the more than 100 inscriptions and that the writers were contemporaneous, indicating that the inscriptions were written in the city of Samaria itself.

The inscriptions list repetitive shipment details of wine and oil supplies to Samaria and span a minimal period of seven years. For archaeologists, they also provide critical insights into the logistical infrastructure of the kingdom of Israel. The inscriptions feature the date of composition (year of a given monarch), commodity type (oil, wine), name of a person, name of a clan and name of a village near the capital. Based on letter-shape considerations, the ostraca have been dated to the first half of the eighth century BCE, possibly during the reign of King Jeroboam II of Israel.

"If only two scribes wrote the examined Samaria texts contemporaneously and both were located in Samaria rather than in the countryside, this would indicate a palace bureaucracy at the peak of the kingdom of Israel's prosperity," Prof. Finkelstein explains.

"Our results, accompanied by other pieces of evidence, seem also to indicate a limited dispersion of literacy in Israel in the early eighth century BCE," Prof. Piasetzky says.

"Our interdisciplinary team harnessed a novel algorithm, consisting of image processing and newly developed machine learning techniques, to conclude that two writers wrote the 31 examined texts, with a confidence interval of 95%," said Dr. Sober, now a member of Duke University's mathematics department.

"The innovative technique can be used in other cases, both in the Land of Israel and beyond. Our innovative tool enables handwriting comparison and can establish the number of authors in a given corpus," adds Faigenbaum-Golovin.

The new research follows up from the findings of the group's 2016 study, which indicated widespread literacy in the kingdom of Judah a century and a half to two centuries later, circa 600 BCE. For that study, the group developed a novel algorithm with which they estimated the minimal number of writers involved in composing ostraca unearthed at the desert fortress of Arad. That investigation concluded that at least six writers composed the 18 inscriptions that were examined.

"It seems that during these two centuries that passed between the composition of the Samaria and the Arad corpora, there was an increase in literacy rates within the population of the Hebrew kingdoms," Dr. Shaus says. "Our previous research paved the way for the current study. We enhanced our previously developed methodology, which sought the minimum number of writers, and introduced new statistical tools to establish a maximum likelihood estimate for the number of hands in a corpus."

Research for the study was conducted by Ph.D. candidate Shira Faigenbaum-Golovin, Dr. Arie Shaus, Dr. Barak Sober and Prof. Eli Turkel, all of TAU's School of Mathematical Sciences; Prof. Eli Piasetzky of TAU's School of Physics; and Prof. Israel Finkelstein, Jacob M. Alkow Professor of the Archaeology of Israel in the Bronze and Iron Ages, of TAU's Sonia and Marco Nadler Institute of Archaeology. The study was published in PLOS ONE.

Next, the researchers intend to use their methodology to study other corpora of inscriptions from various periods and locations.

Source: American Friends of Tel Aviv University [January 22, 2020]

* This article was originally published here

2020 January 25 Rubin’s Galaxy Image Credit: NASA, ESA,...

2020 January 25

Rubin’s Galaxy
Image Credit: NASA, ESA, B. Holwerda (University of Louisville)

Explanation: In this Hubble Space Telescope image the bright, spiky stars lie in the foreground toward the heroic northern constellation Perseus and well within our own Milky Way galaxy. In sharp focus beyond is UGC 2885, a giant spiral galaxy about 232 million light-years distant. Some 800,000 light-years across compared to the Milky Way’s diameter of 100,000 light-years or so, it has around 1 trillion stars. That’s about 10 times as many stars as the Milky Way. Part of a current investigation to understand how galaxies can grow to such enormous sizes, UGC 2885 was also part of astronomer Vera Rubin’s pioneering study of the rotation of spiral galaxies. Her work was the first to convincingly demonstrate the dominating presence of dark matter in our universe.

∞ Source: apod.nasa.gov/apod/ap200125.html

* This article was originally published here

Great Orme Bronze Age Copper Mines, Llandudno, North Wales.

Great Orme Bronze Age Copper Mines, Llandudno, North Wales.

* This article was originally published here

Evidence of specialized sheep-hunting camp discovered in prehistoric Lebanon

Anthropologists at the University of Toronto (U of T) have confirmed the existence more than 10,000 years ago of a hunting camp in what is now northeastern Lebanon - one that straddles the period marking the transition from nomadic hunter-gatherer societies to agricultural settlements at the onset of the last stone age.

Evidence of specialized sheep-hunting camp discovered in prehistoric Lebanon
Views of Nachcharini Cave and environs [Credit: Stephen Rhodes et al. 2020]
Analysis of decades-old data collected from Nachcharini Cave high in the Anti-Lebanon mountain range that forms the modern-day border between Lebanon and Syria, shows the site was a short-term hunting camp that served as a temporary outpost to emerging and more substantial villages elsewhere in the region, and that sheep were the primary game.

The finding confirms the hypothesis of retired U of T archaeologist Bruce Schroeder, who excavated the site on several occasions beginning in 1972, but who had to discontinue his work when the Lebanese Civil War began in 1975.

"The site represents the best evidence of a special-purpose camp - not a village or settlement - in the region," said Stephen Rhodes, a PhD candidate in the Department of Anthropology in the Faculty of Arts & Science at U of T and lead author of a study published in PLOS ONE. "The cave was a contemporary of larger settlements further south in the Jordan Valley, and is the first site of its kind to show the predominance of sheep among the animals hunted by its temporary inhabitants."

Evidence of specialized sheep-hunting camp discovered in prehistoric Lebanon
El Khiam points and variants from Nachcharini, St. 4d
[Credit: Stephen Rhodes et al. 2020]
Radiocarbon dating of animal bones recovered from the site shows that it dates to an era known as the Pre-Pottery Neolithic A (PPNA), a period from about 10,000-8,000 BCE during which the cultivation of crops, the construction of mud-brick dwellings and other practices of domestication began to emerge. The stone tools found at the sites are mostly tiny arrowheads used for hunting. The new dates presented place the main deposits at the cave securely in the PPNA.

"Previous dates established in the 1970s were problematic and far too recent for unknown reasons, possibly due to contamination or incorrect processing," said Rhodes, who coauthored the study with Professors Edward Banning and Michael Chazan, both members of the Department of Anthropology at U of T. "The results highlight the fact that people in the PPNA took advantage of a wide variety of habitats in a complex system of subsistence practices."

It was already known that sheep hunting was practiced in this region throughout periods that preceded the PPNA, and the evidence found at Nachcharini Cave reinforces that understanding. According to Rhodes, it consolidates our knowledge of the natural range of sheep, which pertains to a potential beginning of domestication in later years.

"We are not saying that hunters at Nachcharini were engaged in early stages of this domestication," he said. "But the evidence of a local tradition makes this area a possible centre of sheep domestication later on."

Source: University of Toronto [January 22, 2020]

* This article was originally published here

Unravelling arthropod genomic diversity over 500 million years of evolution

An international team of scientists report in the journal Genome Biology results from a pilot project, co-led by Robert Waterhouse, Group Leader at the SIB Swiss Institute of Bioinformatics and University of Lausanne, to kick-start the global sequencing initiative of thousands of arthropods. Comparative analyses across 76 species spanning 500 million years of evolution reveal dynamic genomic changes that point to key factors behind their success and open up many new areas of research.

Unravelling arthropod genomic diversity over 500 million years of evolution
The i5k pilot project sequenced, assembled, and annotated the genomes of 28 diverse arthropod species,
substantially increasing the current species sampling to explore arthropod genomic diversity over
500 million years of evolution [Credit: Created by Robert M. WaterhouseReuse licensed under
CC BY 4.0Milkweed Bug by Chiaki UedaLong-Horned Beetle by Robert Mitchell]
Friends and foes, arthropods rule the world

Arthropods make up the most species-rich and diverse group of animals on Earth, with numerous adaptations over 500 million years of evolution that have allowed them to exploit all major ecosystems. They play vital roles in the healthy ecology of our planet as well as being both beneficial and detrimental to the success of humankind through pollination and biowaste recycling, or destroying crops and spreading disease.

"By sequencing and comparing their genomes we can begin to identify some of the key genetic factors behind their evolutionary success," explains Waterhouse, "but will the impact of human activities in modern times bring an end to their rule, or will their ability to adapt and innovate ensure their survival?"

The i5k pilot project: kick-starting arthropod genome sequencing

The i5k initiative to sequence and annotate the genomes of 5000 species of insects and other arthropods, was launched in a letter to Science in 2011. From the outset, the initiative aimed to support the development of new genomic resources for understanding the molecular biology and evolution of arthropods.

Since then, the i5k has grown into a broad community of scientists using genomics to study insects and other arthropods in many different contexts from fundamental animal biology, to effects on ecology and the environment, and impacts on human health and agriculture.

To kick-start the i5k, a pilot project was launched at the Baylor College of Medicine led by Stephen Richards to sequence, assemble, and annotate the genomes of 28 diverse arthropod species carefully selected from 787 community nominations.

Large-scale multi-species genome comparisons

"The identification and annotation of thousands of genes from the i5k pilot project substantially increases our current genomic sampling of arthropods," says Waterhouse.

The evolutionary innovations of insects and other arthropods are as numerous as they are wondrous, from terrifying fangs 
and stingers to exquisitely coloured wings and ingenious feats of engineering. DNA sequencing allows us to chart the 
genomic blueprints underlying this incredible diversity that characterises the arthropods and makes them the most 
successful group of animals on Earth. An international team of scientists report in the journal Genome Biology results 
from a pilot project, co-led by SIB Group Leader Robert Waterhouse at the University of Lausanne, to kick-start the
 global sequencing initiative of thousands of arthropods. Comparative analyses across 76 species spanning 
500 million years of evolution reveal dynamic genomic changes that point to key factors behind 
their success and open up many new areas of research [Credit: Robert Waterhouse]

Combining these with previously sequenced genomes enabled the researchers to perform a large-scale comparative analysis across 76 diverse species including flies, butterflies, moths, beetles, bees, ants, wasps, true bugs, thrips, lice, cockroaches, termites, mayflies, dragonflies, damselflies, bristletails, crustaceans, centipedes, spiders, ticks, mites, and scorpions.

PhD students Gregg Thomas from Indiana University, USA, and Elias Dohmen from the University of Munster, Germany, used the annotated genomes to perform the computational evolutionary analyses of more than one million arthropod genes.

Dynamic gene family evolution - a key to success?

The team's analyses focused on tracing gene evolutionary histories to estimate changes in gene content and gene structure over 500 million years. This enabled identification of families of genes that have substantially increased or decreased in size, or newly emerged or disappeared, or rearranged their protein domains, between and within each of the major arthropod subgroups.

The gene families found to be most dynamically changing encode proteins involved in functions linked to digestion, chemical defence, and the building and remodelling of chitin - a major part of arthropod exoskeletons.

Adaptability of digestive processes and mechanisms to neutralise harmful chemicals undoubtedly served arthropods well as they conquered a wide variety of ecological niches. Perhaps even more importantly, the flexibility that comes with a segmented body plan and a dynamically remodellable exoskeleton allowed them to thrive by physically adapting to new ecosystems.

Innovation through invention and repurposing

Newly evolved gene families also reflect functions known to be important in different arthropod groups, such as visual learning and behaviour, pheromone and odorant detection, neuronal activity, and wing development. These may enhance food location abilities or fine-tune species self-recognition and communication.

In contrast, few changes were identified in the ancestor of insects that undergo complete metamorphosis: the dramatic change from the juvenile form to the fully developed adult (like a caterpillar transforming into a butterfly). This has traditionally been thought of as a major step in the evolution of insects from the original state of developing through gradual nymph stages until finally reaching the adult stage.

"These findings support the idea that this key transition is more likely to have occurred through the rewiring of existing gene networks or building new networks using existing genes, a scenario of new-tricks-for-old-genes" explains Waterhouse.

Genomic insights into arthropod biology and evolution

Several detailed genomic studies of individual i5k species have focused on their fascinating biological traits such as the feeding ecology and developmental biology of the milkweed bug, insecticide resistance, blood feeding, and traumatic sex of the bed bug, horizontal gene transfer from bacteria and fungi and digestion of plant materials by the Asian long-horned beetle, and parasite-host interactions and potential vaccines for the sheep blowfly. The combined analyses reveal dynamically changing and newly emerged gene families that will stimulate new areas of research.

"We can take these hypotheses into the lab and use them to directly study how the genome is translated into visible morphology at a resolution that cannot be achieved with any other animal group," says co-lead author, Ariel Chipman, from the Hebrew University of Jerusalem, Israel.

The new resources substantially advance progress towards building a comprehensive genomic catalogue of life on our planet, and with more than a million described arthropod species and estimates of seven times as many, there clearly remains a great deal to discover!

Next steps in arthropod genomics and beyond

More effective and cost-efficient DNA sequencing technologies mean that new ambitious initiatives are already underway to sequence the genomes of additional arthropods. These include the Global Ant Genome Alliance and the Global Invertebrate Genomics Alliance, as well as the Darwin Tree of Life Project that is targeting all known species of animals in the British Isles, and the global network of communities coordinated by the Earth BioGenome Project (EBP) that aims to sequence all of Earth's eukaryotic biodiversity7.

The EBP's goals also include benefitting human welfare, where the roles of arthropods are clear and the hidden benefits are likely to be substantial, as well as protecting biodiversity and understanding ecosystems, where alarming reports of declining numbers make arthropods a priority.

"The completion of the i5k pilot project therefore represents an important milestone in the progress towards intensifying efforts to develop a comprehensive genomic catalogue of life on our planet", concludes Richards.

Source: Swiss Institute of Bioinformatics [January 23, 2020]

* This article was originally published here

Clays in Antarctica from millions of years ago reveal past climate changes

Members of the TASMANDRAKE research group of the Andalusian Earth Sciences Institute (IACT), which pertains to the University of Granada and CSIC, have published a research paper in the prestigious international journal Scientific Reports describing their analysis of clays from Antarctica dating back 35.5 million years, to reconstruct past climate changes.

Clays in Antarctica from millions of years ago reveal past climate changes
Glaucony grains observed under an electron microscope
[Credit: University of Granada]
Their study was conducted in the area known as Drake Passage—the body of water that separates South America from Antarctica, between Cape Horn (Chile) and the South Shetland Islands (Antarctica). The results help to better understand the climatic conditions prior to the formation of the Antarctic Circumpolar Current, thus evaluating possible links between the development of the ice sheet in Antarctica and the changes in the tectonic and paleoceanographic configuration. Such questions constitute key facets of past climate functioning that provide boundary conditions for today's climate models, which predict a general rise in sea levels over the coming centuries.

The article analyses the relevance as a climatic indicator of the mineral commonly known as 'glauconite', which is more properly termed 'the glauconia facies' or 'glauconia'. This is a type of green clay, formed mainly in shallow marine environments (<500 m) with temperatures below 15° C, under very specific oxygenation conditions.

The existence of this clay formation in the Antarctic region has received little scholarly attention to date compared to other geological records on the planet. The characteristic green-coloured mineral has been observed around Antarctica and the Antarctic Ocean in sedimentary sequences of the Terminal Eocene Event—that is, before one of the main climatic transitions in Earth's history. The Eocene–Oligocene climate transition took place approximately 34–33.6 million years ago.

Clays in Antarctica from millions of years ago reveal past climate changes
Northwest region of the Antarctic Peninsula (South Shetland Islands)
[Credit: University of Granada]
This scientific contribution describes, for the first time in the Antarctic Ocean, a glauconitisation event (in which glauconia was formed) approximately 35.5 million years ago in the Weddell Sea, northeast of the Antarctic Peninsula between South America and Antarctica.

The formation of glauconia 35.5 million years ago marks the onset of progressive sea level rise in the north Weddell Sea during the Terminal Eocene. The results of this scientific study thus provide new insights regarding changes in paleoceanographic conditions just prior to the Eocene–Oligocene climate transition and the controversial opening and deepening of Drake Passage.

Studying the weather of the past to predict the future

The separation of the Antarctic continent from South America and Oceania allowed bodies of water to transfer freely between the Pacific and Atlantic Oceans. This new circulation of bodies of water resulted in the Circumpolar Current and, with it, the thermal insulation of the Antarctic and the formation of the ice cap on a continental scale.

Clays in Antarctica from millions of years ago reveal past climate changes
Map of Antarctica showing the location of the Antarctic Circumpolar Current (ACC), which flows from west to east.
The ACC is a fundamental element in the deep global circulation connecting the Pacific, Atlantic, and Indian
Oceans. It is therefore an important part of the global ocean circulation network that distributes
 heat around the Earth [Credit: University of Granada]
The opening of Drake Passage between South America and the Antarctic Peninsula is therefore considered one of the most important events in the history of the Earth's oceanic and atmospheric circulation. However, in the absence of dating for the formation of the sedimentary basins of Drake Passage, it is difficult to specify the precise age when the Passage began to open up and the Circumpolar Current started to form. The glauconia analysis conducted by the TASMANDRAKE research group contributes to progress in this area of study.

To put these changes into perspective, Adrian Lopez Quiros, the principal author of the research, notes that "it is necessary to study the past to understand the present and help predict the future," by better understanding the tectonic, climatic, and paleoceanographic conditions that led to the onset and subsequent evolution of this important ocean current.

The United Nations' Intergovernmental Panel on Climate Change (IPCC), a major reference source for climate forecasts, established several possible future climate scenarios in 2014. However, the new data, when comparing simulations with real-world data, predict even greater impacts than those previously foreseen in the IPCC climate scenarios. Therefore, climate change is developing faster than previously thought. With its research, the TASMANDRAKE group aims to provide new variables for these models—focusing on sediments and geophysics—to ensure that its results reflect real-life events even more accurately, especially in terms of the transoceanic currents, global warming, and rising sea levels.

Source: University of Granada [January 23, 2020]

* This article was originally published here

Mount Vesuvius blast turned ancient victim’s brain to glass

The eruption of Mount Vesuvius turned an incinerated victim’s brain material into glass, the first time scientists have verified the phenomenon from a volcanic blast, officials at the Herculaneum archaeology site said Thursday.

Mount Vesuvius blast turned ancient victim’s brain to glass
This photo shows a fragment of brain material of a victim incinerated by the ancient blast
of Mount Vesuvius and turned into glass [Credit: Herculaneum press office via AP]
Archaeologists rarely recover human brain tissue, and when they do it is normally smooth and soapy in consistency, according to an article detailing the discovery in the New England Journal of Medicine. The eruption of Vesuvius in the year 79 instantly killed the inhabitants of Pompeii and neighboring Herculaneum, burying an area 20 kilometers (12 miles) from the volcano in ash in just a few hours.

The remains of a man lying on a wooden bed were discovered at Herculaneum, closer to Vesuvius than Pompeii, in the 1960s. He is believed to have been the custodian of a place of worship, the Collegium Augustalium.

A team led by Pier Paolo Petrone, a forensic anthropologist at the Federico II University in Naples, determined that the victim’s brain matter had been vitrified, a process by which tissue is burned at a high heat and turned into glass, according to the new study. The fragments presented as shards of shiny black material spotted within remnants of the victim’s skull.

Mount Vesuvius blast turned ancient victim’s brain to glass
The unfortunate victim's final resting place outside a building in Herculaneum
[Credit: Pier Paolo Petrone]
A study of the charred wood nearby indicates a maximum temperature of 520 degrees Celsius (968 degrees Fahrenheit). "This suggests that extreme radiant heat was able to ignite body fat and vaporize soft tissue," the study said.

The resulting solidified spongy mass found in the victim’s chest bones is also unique among other archaeological sites and can be compared with victims of more recent historic events like the firebombing of Dresden and Hamburg in World War II, the article said.

The flash of extreme heat was followed by a rapid drop in temperatures, which vitrified the brain material, the authors said.

"This is the first time ever that vitrified human brain remains have been discovered resulting from heat produced by an eruption," Herculaneum officials said.

Source: Associated Press [January 23, 2020]

* This article was originally published here

UK museums may have to follow 'decolonisation' checklist

British museums will be asked to assess their collections with a new "decolonising" checklist to ease the repatriation of cultural treasures, and could face financial repercussions if they fail to do so.

UK museums may have to follow 'decolonisation' checklist
Arts Council England has called on experts to draw up new guidelines to address sacred and
significant objects like the Parthenon Marbles and Rosetta Stone [Credit: Telegraph]
Arts Council England has called on experts to draw up new guidelines to address sacred and significant objects like the Parthenon Marbles and Rosetta Stone, which have long provoked pleas for repatriation from aggrieved nations after being seized in the age of empire.

The Government-backed body already requires its portfolio organisations to follow protocols on diversity in order to receive funding, so could demand institutions adhere to its planned credo on colonialism.

It is hoped the checklist would be followed by all UK museums and fill a gap in guidance, but the Arts Council said it was “too soon” to say there would be a financial impact for the organisations it funds.

The guidance will urge UK institutions to be “proactive” about repatriation, and navigating divided public opinion surrounding contested collections.

Following the example of France, where repatriation of colonial spoils has been accelerated by the promises of Emmanuel Macron, experts will be contracted to help UK museums deal with media attention, Government policy, and the long-term future of priceless artefacts.

UK museums may have to follow 'decolonisation' checklist
Easter Islanders have demanded return of the Hoa Hakananai’a statue
[Credit: Londstephen Chung/LNPON News Pictures Ltd]
An Arts Council spokeswoman said: “The aim of the guidance is to encourage a more proactive and coordinated approach across the UK museum sector by providing museums with a practical resource to support them in engaging with and responding to all aspects of restitution and repatriation.

“At this point we’re focused on developing and providing the guidance.”

The Arts Council said it was “too soon” to comment on financial arrangements , or groups being required to follow guidance in order to receive funding, in the same way diversity practices must be demonstrated by the 828 organisations within its portfolio.

An Easter Island Moai looming in the British Museum, an Aboriginal shield, and Ethiopian sacred tablets are among the many artefacts acquired amid imperial expansion which have been demanded back by their ancestral owners.

Last year Cambridge University’s Jesus College handed back a Benin bronze cockerel to Nigeria following student pressure to repatriate the plundered object, and the University of Manchester returned Aboriginal artifacts to their original communities.

UK museums may have to follow 'decolonisation' checklist
Artefacts like this sarcophagus have been repatriated in the past
[Credit: EPA]
Foreseeing ever-increasing demands for repatriation in future, the Arts Council has offered a £42,000 contract to experts who can draw up guidance on decolonisation.

The contract states: “There is significant government, public and press interest and increasing calls for action by UK museums and sector bodies to address this agenda.”

It is understood that planned guidance will work as a checklist to handle claims, from how to deal with publicity and activist agitation, to possible repatriation.

The guidance will urge museums to be proactive in assessing their collections, recognising the potential colonial history of items, and working to educate visitors on both the objects and their provenance.

The Arts Council is keen to stress these benefits of decolonisation, which may lead to items being removed from collections, but can give curators and the public a greater knowledge and appreciation of the objects themselves.

UK museums may have to follow 'decolonisation' checklist
Cambridge University returned this Benin bronze cockerel to Nigeria
[Credit: AFP]
The organisation I understood not to be making moral judgments in the call for guidance, either for or against repatriation, but wishes to provide a uniform template for best practice across the sector.

It is understood future funding may help foreign delegations appraise objects in British museums which could be ripe for repatriation, and the the Arts Council would welcome the range of perspectives on decolonisation provided by staff diversity.

Author: Craig Simpson | Source: Telegraph [January 17, 2020]

* This article was originally published here


https://t.co/hvL60wwELQ — XissUFOtoday Space (@xufospace) August 3, 2021 Жаждущий ежик наслаждается пресной водой после нескольких дней в о...