пятница, 27 декабря 2019 г.

Iron Age Decorated Mount, National Museum of Scotland, Edinburgh, 27.12.19.

Iron Age Decorated Mount, National Museum of Scotland, Edinburgh, 27.12.19.

* This article was originally published here

Could Greece force EU to demand repatriation of Parthenon Sculptures after Brexit?

As Britain leaves the European Union, it is taking with it one of its members’ most invaluable cultural treasures. It is likely now that the issue of the repatriation of the Parthenon sculptures will take on a new dimension.

Could Greece force EU to demand repatriation of Parthenon Sculptures after Brexit?
Credit: Getty Images
As a member of the EU, Britain remained adamant about the British Museum’s rightful ownership of the sculptures in response to Greece’s repeated requests that they be returned.

The British government even argued at one point that the British Museum itself does not belong to the state; therefore there is nothing that can be done about the issue on a governmental level.

However, it seems that a tiny window may be opening for a new claim that the priceless marbles belong to Greece for cultural and ethical reasons, regardless of any and all arguments of legal ownership by the British Museum.

After Britain’s withdrawal from the Union, the country will have to sign new agreements with the EU on a range of important issues. One of these concerns the realm of culture and cultural artifacts.

And without a doubt, Greece’s ancient Parthenon sculptures belong to this category, and take pride of place in it.

What Greece can push for now is the issue of the repatriation of these particular cultural artifacts to their original and rightful owners, regardless of any possible claims of legality from centuries ago expressed by the British Museum.

Greece has made official appeals to repatriate the priceless historical treasures since the mid-1980s, with then-Minister of Culture Melina Mercouri rallying for this cause for years.

In 2015, the United Nations began an initiative called “The Restitution or Return of Cultural Property in the Countries of Origin,” which includes an explicit reference to the return of the Parthenon Marbles.

A total of 74 countries, including many European Union member states, a significant number of Latin American countries and several Arab and African states are involved in the initiative.

Besides UNESCO, Greece has tried to find justice in international courts on the issue, but to no avail — at least until now. The British Museum went as far as to claim that Greece has no legal rights to the sculptures whatsoever and that they are better protected on its premises than they would be in Greece.

Ironically, while the museum and the British government have been firmly against the repatriation of the invaluable artifacts, the majority of UK citizens are overwhelmingly in support of the reunification of the Greek marbles.

A 2017 poll showed fully 69 percent of Britons were in favor of returning the marbles, while only a mere 13 percent were against the repatriation.

Perhaps most ironically, Britain’s new Prime Minister Boris Johnson is also against the returning of the cultural treasures to Greece. This is especially surprising because Johnson is an outspoken philhellene, who has always admired ancient Greek civilization and its invaluable contributions to western culture.

In fact, Johnson has even been quoted as saying that the marbles “…were rescued quite rightly by Elgin.”

What Greece simply must do now is bring the issue of the repatriation of the Parthenon sculptures to the Brexit negotiation table. All negotiations on any cultural issues whatsoever must absolutely include these priceless marbles.

As a member of the European Union, Greece can at last take a hard stance and use its veto power in all future deals made between Great Britain and the EU. Greece must force the EU to demand the repatriation of the Parthenon marbles as part of the Brexit deal.

Greece has the UNESCO decision, the majority of EU member states, a total of 74 countries — and even a majority of Britons — on its side to correct a wrong that has been perpetuated for over 200 years.

Lord Elgin and the plundered sculptures

Thomas Bruce, the Seventh Earl of Elgin, served as the British ambassador to Constantinople. He was a great admirer of ancient Greece and asked the Ottoman rulers of Greece at the time for the authority to replicate some of the sculptures of the Parthenon.

Elgin was somehow even given permission to chip away and remove some of the sculptures from the mighty edifice as well.

He removed portions of the frieze, along with the metopes and pedimental sculptures of the Parthenon as well as sculptured slabs from the Athenian temple of Nike Apteros, in addition to various antiquities from Attica and other areas of Greece which caught his eye.

Part of the Elgin collection was prepared for shipping to England in 1803, but his ship, the Mentor, wrecked near Cerigo with its priceless cargo of marbles. It was not until after the labors of three years, and the expenditure of large sums of money, that the marbles were successfully recovered by divers.

After acquiring this first booty of plundered antiquities, Elgin continued to make additions to his collection as late as 1812, when eighty new cases full of antiquities arrived on English shores for his delight and delectation.

The British Museum continues to claim that Lord Elgin did not “steal” the artifacts. Instead, the Museum insists that Elgin took them with the complete knowledge and permission of the Ottoman authorities. Taking into account the fact that the Ottomans had invaded Greece, and had no part in the production of these Greek antiquities, somehow has been left out of the equation.

It is estimated that Elgin looted some 247 feet of frieze sculptures from the Parthenon. Furthermore, it is believed that Elgin took around half of what was still standing of the Parthenon structure itself at that time.

After Elgin shipped all his loot to England, he sold the sculptures in 1816 for £35,000. Eventually, they were acquired by the British Museum in London.

However, even back in the early 1800s, the legitimacy of the ownership of the marbles was controversial. Only after a Parliamentary Select Committee debated the legality of Elgin’s ownership, when Elgin argued that the sculptures would be better cared for in Britain than in Greece, did the museum finally take possession of the Parthenon antiquities.

Author: Philip Chrysopoulos | Source: Greek Reporter [December 20, 2019]

* This article was originally published here

NASA's Fermi Mission links nearby pulsar's gamma-ray 'halo' to antimatter puzzle

NASA's Fermi Gamma-ray Space Telescope has discovered a faint but sprawling glow of high-energy light around a nearby pulsar. If visible to the human eye, this gamma-ray "halo" would appear about 40 times bigger in the sky than a full Moon. This structure may provide the solution to a long-standing mystery about the amount of antimatter in our neighbourhood.

NASA's Fermi Mission links nearby pulsar's gamma-ray 'halo' to antimatter puzzle
This animation shows a region of the sky centered on the pulsar Geminga. The first image shows the total number of
gamma rays detected by Fermi’s Large Area Telescope at energies from 8 to 1,000 billion electron volts (GeV) — billions
 of times the energy of visible light — over the past decade. By removing all bright sources, astronomers discovered
the pulsar’s faint, extended gamma-ray halo [Credit: NASA/DOE/Fermi LAT Collaboration]
"Our analysis suggests that this same pulsar could be responsible for a decade-long puzzle about why one type of cosmic particle is unusually abundant near Earth," said Mattia Di Mauro, an astrophysicist at the Catholic University of America in Washington and NASA's Goddard Space Flight Center in Greenbelt, Maryland. "These are positrons, the antimatter version of electrons, coming from somewhere beyond the solar system."

A neutron star is the crushed core left behind when a star much more massive than the Sun runs out of fuel, collapses under its own weight and explodes as a supernova. We see some neutron stars as pulsars, rapidly spinning objects emitting beams of light that, much like a lighthouse, regularly sweep across our line of sight.

Geminga, discovered in 1972 by NASA's Small Astronomy Satellite 2, is among the brightest pulsars in gamma rays. It is located about 800 light-years away in the constellation Gemini. Geminga's name is both a play on the phrase "Gemini gamma-ray source" and the expression "it's not there" -- referring to astronomers' inability to find the object at other energies -- in the dialect of Milan, Italy.

Geminga was finally identified in March 1991, when flickering X-rays picked up by Germany's ROSAT mission revealed the source to be a pulsar spinning 4.2 times a second.

NASA's Fermi Mission links nearby pulsar's gamma-ray 'halo' to antimatter puzzle
This model of Geminga's gamma-ray halo shows how the emission changes at different energies, a result of two effects.
The first is the pulsar's rapid motion through space over the decade Fermi's Large Area Telescope has observed it.
Second, lower-energy particles travel much farther from the pulsar before they interact with starlight and boost
it to gamma-ray energies. This is why the gamma-ray emission covers a larger area at lower energies. One
GeV represents 1 billion electron volts — billions of times the energy of visible light
[Credit: NASA’s Goddard Space Flight Center/M. Di Mauro]
A pulsar naturally surrounds itself with a cloud of electrons and positrons. This is because the neutron star's intense magnetic field pulls the particles from the pulsar's surface and accelerates them to nearly the speed of light.

Electrons and positrons are among the speedy particles known as cosmic rays, which originate beyond the solar system. Because cosmic ray particles carry an electrical charge, their paths become scrambled when they encounter magnetic fields on their journey to Earth. This means astronomers cannot directly track them back to their sources.

For the past decade, cosmic ray measurements by Fermi, NASA's Alpha Magnetic Spectrometer (AMS-02) aboard the International Space Station, and other space experiments near Earth have seen more positrons at high energies than scientists expected. Nearby pulsars like Geminga were prime suspects.

Then, in 2017, scientists with the High-Altitude Water Cherenkov Gamma-ray Observatory (HAWC) near Puebla, Mexico, confirmed earlier ground-based detections of a small gamma-ray halo around Geminga. They observed this structure at energies from 5 to 40 trillion electron volts -- light with trillions of times more energy than our eyes can see.

Scientists think this emission arises when accelerated electrons and positrons collide with nearby starlight. The collision boosts the light up to much higher energies. Based on the size of the halo, the HAWC team concluded that Geminga positrons at these energies only rarely reach Earth. If true, it would mean that the observed positron excess must have a more exotic explanation.

But interest in a pulsar origin continued, and Geminga was front and center. Di Mauro led an analysis of a decade of Geminga gamma-ray data acquired by Fermi's Large Area Telescope (LAT), which observes lower-energy light than HAWC.

"To study the halo, we had to subtract out all other sources of gamma rays, including diffuse light produced by cosmic ray collisions with interstellar gas clouds," said co-author Silvia Manconi, a postdoctoral researcher at RWTH Aachen University in Germany. "We explored the data using 10 different models of interstellar emission."

What remained when these sources were removed was a vast, oblong glow spanning some 20 degrees in the sky at an energy of 10 billion electron volts (GeV). That's similar to the size of the famous Big Dipper star pattern -- and the halo is even bigger at lower energies.

NASA's Fermi Mission links nearby pulsar's gamma-ray 'halo' to antimatter puzzle
Particles travelling near light speed can interact with starlight and boost it to gamma-ray energies. This animation
shows the process, known as inverse Compton scattering. When light ranging from microwave to ultraviolet
 wavelengths collides with a fast-moving particle, the interaction boosts it to gamma rays, the most
energetic form of light [Credit: NASA's Goddard Space Flight Center]
"Lower-energy particles travel much farther from the pulsar before they run into starlight, transfer part of their energy to it, and boost the light to gamma rays. This is why the gamma-ray emission covers a larger area at lower energies ," explained co-author Fiorenza Donato at the Italian National Institute of Nuclear Physics and the University of Turin. "Also, Geminga's halo is elongated partly because of the pulsar's motion through space."

The team determined that the Fermi LAT data were compatible with the earlier HAWC observations. Geminga alone could be responsible for as much as 20% of the high-energy positrons seen by the AMS-02 experiment. Extrapolating this to the cumulative emission from all pulsars in our galaxy, the scientists say it's clear that pulsars remain the best explanation for the positron excess.

"Our work demonstrates the importance of studying individual sources to predict how they contribute to cosmic rays," Di Mauro said. "This is one aspect of the exciting new field called multimessenger astronomy, where we study the universe using multiple signals, like cosmic rays, in addition to light."

A paper detailing the findings was published in the journal Physical Review D.

Author: Francis Reddy | Source: NASA/Goddard Space Flight Center [December 19, 2019]

* This article was originally published here

Fossil research unveils new turtle species, hints at intercontinental migrations

The Arlington Archosaur Site (AAS) of Texas preserves remnants of an ancient Late Cretaceous river delta that once existed in the Dallas-Fort Worth area. Known for discoveries of fossil crocodiles and dinosaurs, a multi-institution research team has described four extinct turtle species, including a new river turtle named after AAS paleontologist Dr. Derek Main and the oldest side-necked turtle in North America. These new turtles include an intriguing combination of native North American forms alongside Asian and Southern Hemisphere immigrants, suggesting extensive intercontinental migration of turtles during this time.

Fossil research unveils new turtle species, hints at intercontinental migrations
Arlington Archosaur Site (AAS) fossil samples of new turtle species "Trinitichelys" maini
[Credit: Brent Adrian, M.F.A.]
Originally discovered by amateur fossil hunter Art Sahlstein in 2003, the AAS is a prolific fossil locality found in the middle of a suburban subdivision. The AAS preserves remnants of an ancient Late Cretaceous river delta around 96 million years ago in what is today the Dallas-Fort Worth area. It preserves a record of a freshwater wetland that sat near the shore of a large peninsula, including a diverse assemblage of crocodile relatives, dinosaurs, amphibians, mammals, fish, invertebrates, and plants, several of which are also new species awaiting description.

"Until this discovery, there were very few turtle fossils from this time period discovered in Appalachia," says Dr. Heather Smith, one of the authors of the paper. The research team describing these discoveries includes Brent Adrian, M.F.A., Heather F. Smith, Ph.D., and Ari Grossman, Ph.D., from Midwestern University in Glendale Arizona, and Christopher Noto, Ph.D., from University of Wisconsin-Parkside.

Fossil research unveils new turtle species, hints at intercontinental migrations
Map of North America during the Cenomanian age (96 million years ago) showing the four turtle families newly
discovered at the Arlington Archosaur Site (AAS). The AAS fossil assemblage includes a diverse combination
of native North American turtle lineages alongside those that migrated from Asia or the Southern hemisphere.
One of these species, "Trinitichelys" maini is a new species to science, described here for the first time
[Credit: Brent Adrian, M.F.A.]
"The AAS turtle assemblage informs a growing understanding of Appalachian ecosystems in the mid-Cretaceous, most of which were obscured by later erosion along coasts and extensive continental river drainages,'' said Brent Adrian, the lead author of the study, published in the current issue of the online journal Palaeontologia Electronica.

One new species—"Trinitichelys" maini—is a baenid turtle, an extinct lineage of aquatic North American turtles that persisted from the Early Cretaceous through the Eocene. These turtles were medium-sized (about the size of a modern snapping turtle), had heavily fused bones and shells, and occupied freshwater river habitats. "Trinitichelys" maini is the oldest member of the group found in the eastern North American subcontinent of Appalachia, which at that time was separated from Laramidia, the western sub-continent of North America.

Fossil research unveils new turtle species, hints at intercontinental migrations
Arlington Archosaur Site (AAS) fossil samples of new turtle species "Trinitichelys" maini
[Credit: Brent Adrian, M.F.A.]
"T." maini honors the late Dr. Derek Main, the first director of the AAS project, who recognized the scientific potential of the site. "Derek's incredible work with the community led to the creation of one of the most extensive and diverse collections of mid-Cretaceous fossils known in Texas," says Dr. Chris Noto, who took over as director of the AAS in 2013, "He was an inspiration to all those who worked with him, and it is only fitting this new species is named after him."

Alongside T. maini, the study describes three more intriguing new turtles from the AAS. One species represents the oldest side-necked (pleurodire) turtle discovered in North America. Side-necked turtles originated in the Southern Hemisphere, and the AAS marks the first time they are found in North America.

Yet another surprise is an early soft-shelled turtle (trionychid), which belongs to a lineage that immigrated from Asia. Adding to this unusual mix is Naomichelys sp., a large semi-aquatic turtle with unusual tubercles (raised bumps) on its shell that is a relict North American species typically found in much older rocks. This combination of turtle species in one location is unique, as it includes Asian, Southern Hemisphere, and native North American forms, and both young and older, relict taxa.

Source: Midwestern University [December 23, 2019]

* This article was originally published here

2019 December 27 A Partial Solar Eclipse Sequence Reflected...

2019 December 27

A Partial Solar Eclipse Sequence Reflected
Image Credit & Copyright: Majid Ghohroodi

Explanation: What’s happened to the Sun? Yesterday, if you were in the right place at the right time, you could see the Sun rise partially eclipsed by the Moon. The unusual sight was captured in dramatic fashion in the featured image not only directly, in a sequence of six images, but also in reflection from Soltan Salt Lake in Iran. The almost-white Sun appears dimmer and redder near the horizon primarily because Earth’s atmosphere preferentially scatters away more blue light. Yesterday’s partial solar eclipse appeared in the sky over much of Asia and Australia, but those with a clear enough sky in a thin band across the Earth’s surface were treated to a more complete annular solar eclipse – where the Moon appears completely surrounded by the Sun in what is known as a ring of fire. The next annular solar eclipse will occur in 2020 June.

∞ Source: apod.nasa.gov/apod/ap191227.html

* This article was originally published here

Ancient wasp-mimicking fly discovered in South Korea

New species was named Buccinatormyia gangnami, after a famous hit by a South Korean singer PSY. It was described based on six impression fossils found near Jinju city in South Korea. On average, members of this species were twice larger than the common house fly, with a proboscis length up to 5 mm. Their darkish abdomenon were embellished with four pairs of light spots, very similar to yellowjacket patterns which typically displayed by hoverflies and other extant flower-loving Diptera active during the day.

Ancient wasp-mimicking fly discovered in South Korea
The long-proboscid fly Buccinatormyia gangnami from the Lower Cretaceous of South Korea
[Credit: Alexander Khramov, Gi-Soo Nam]
The chief model for modern yellowjacket mimics are social wasps united into the Vespidae family. In our time these wasps as really common as everyone knows who has ever seen them stuck in his or her jam.

However, judging by the fossil record, vespid wasps were rare and represented by exclusively solitary taxa in the Early Cretaceous. So probably Buccinatormyia gangnami mimicked something else, or, alternatively, vespid wasps radiated early than currently thought.

Ancient wasp-mimicking fly discovered in South Korea
The fossil fly Buccinatormyia gangnami and the related living wasp mimic fly Stratiomys
[Credit: Alexander Khramov, Gi-Soo Nam]
Buccinatormyia gangnami belongs to Zhangsolvidae, a dipteran family which prospered during the Early Cretaceous, but then went extinct due to unknown causes.

"There were several lineages of long-proboscid flies during the Mesozoic, and all they were initially associated with gymnosperms. Some were managed to survive into our time, while others disappeared, probably due to their inability to adapt themselves to angiosperm-dominated worlds. Why zhangsolvids were destined to lose, we cannot explain yet", said Alexander Khramov, study's leading author and a senior researcher at the Borissiak Paleontological Institute (Moscow).

The details are outline in Alcheringa: An Australasian Journal of Palaeontology.

Source: AKSON Russian Science Communication Association [December 23, 2019]

* This article was originally published here

Cultural evolution caused broad-scale historical declines of large mammals across China

Cultural evolution has been the dominant driver of range contractions in megafauna taxa across China since the beginning of the Common Era, with little or no direct importance of climate. A research team led by Aarhus University along with collaborators from Nanjing University analyzed maps of megafauna distribution dynamics and societal development based on Chinese archival records alongside data on climate across China from 2 to 1953 CE.

Cultural evolution caused broad-scale historical declines of large mammals across China
The Sumatran rhinoceros (Dicerorhinus sumatrensis) was widely distributed in eastern China in historical times,
but was extirpated due to increasing human pressure -- and process that has continued to the present
 day in its remaining range in southeast Asia, threatening to cause the complete extinction
of this species, with likely less than 80 individuals surviving, all in Indonesia
[Credit: Drawing by Friedrich Wilhelm Kuhnert/WikiCommons]
Human activities are now playing a dominant role in driving changes in Earth's biodiversity and are responsible for the incipient sixth mass extinction, but the historical processes leading to this situation are poorly understood, often without emphasis on cultural evolution as a potential key process underlying anthropogenic impacts. A team of researchers from Aarhus University and Nanjing University has now shown that cultural evolution overshadowed climate change in driving historical broad-scale biodiversity dynamics.

By mining the deep Chinese administrative records in relation to culturally important wild megafauna species as well as sociocultural development, the researchers identified the millennia-long spread of agricultural land and agricultural intensification, as well as the specific expansion of the Han culture, as the main cause of the extirpation of five megafauna species from much of China, with little or no direct importance of climate.

Cultural evolution, not climate change, as the main driver

"China's well-preserved written records for more than 2000 years provide a unique opportunity to reconstruct long-term dynamics of culture-nature interactions across large geographical extents," says senior author Professor Jens-Christian Svenning, director of Center for Biodiversity Dynamics in a Changing World (BIOCHANGE), Aarhus University. The five studied megafauna taxa include Asiatic elephant (Elephas maximus), Asian rhinoceroses (Rhinoceros sondaicus, R. unicornis and Dicerorhinus sumatrensis), tiger (Panthera tigris), Asiatic black bear (Ursus thibetanus), and brown bear (Ursus arctos), all of which were widely distributed across the study area and have played an important role in ancient China's cultural activities.

Cultural evolution caused broad-scale historical declines of large mammals across China
Map of the northern boundary of Asian elephant (Elephas maximus) in the study area over the past four millennia, based
on multiple archaeological and historical sources. The distribution dynamics were inconsistent with the trend of mean
 annual temperature across the study area. Oracle bone scripts were used for divination by a cultural group recognized
as Chinese ancestors ruling much of the North China Plain. The significant similarity between these scripts and
their modern forms for the large mammals supports the past wide distribution of these taxa in ancient China
[Credit: Shuqing Teng]
"Ancient China used to host a highly biodiverse assemblage of large mammals even in its nowadays densely populated areas such as the North China Plain and the Middle-Lower Yangtze Plain. Our research shows that the relatively recent loss of this rich megafauna in large part can be attributed to the southward expansion of intensified agricultural practices with the Han culture, which originated in North China," explains postdoc Shuqing Teng from Aarhus University and Nanjing University, the first author of the study.

Regional extirpation of these taxa from the study area were consistent with the sociocultural dynamics described above, but inconsistent with climate change. There were at least two conspicuous cooling-warming cycles during the last 2,000 years, including the Medieval Warm Period and the Little Ice Age, with fluctuations of mean annual temperature around 1 to 1.5 °C, but neither had a conspicuous effect on the megafauna range dynamics.

Importance of cultural filtering

The study provides clear evidence that cultural evolution historically has overshadowed past climate change in shaping broad-scale megafauna patterns, in contrast to the common belief that human societies were unimportant in driving biodiversity dynamics at such large spatiotemporal scales until recent time frames such as the Industrial Revolution or the Great Acceleration of the 20th century.

This finding highlights the importance of culture's role in filtering current ecological assemblages from historical species pools. Perspectives through the lens of cultural filtering should also stimulate thoughts on what is natural—notably helping to overcome the Shifting Baseline Syndrome, the tendency to accept an already degraded state as natural due to lacking recognition of earlier declines—and which natural world we aim to conserve or restore.

Furthermore, modification of cultural filters will be key to responding to the challenges of the Anthropocene biodiversity crisis, as it is fundamentally culturally driven, as shown by this study of historical China, and how to achieve this is an important research challenge.

The findings are published in the Proceedings of the National Academy of Sciences.

Source: Aarhus University [December 23, 2019]

* This article was originally published here

Pictish Sculptured Stones (including the Pictish Inverness Wolf (Image 1)), Inverness Museum and...

Pictish Sculptured Stones (including the Pictish Inverness Wolf (Image 1)), Inverness Museum and Gallery, Inverness, Scotland, 21.12.19.

* This article was originally published here

Climate change not the only threat to vulnerable species, habitat matters

Though climate change is becoming one of the greatest threats to the Earth's already stressed ecosystems, it may not be the most severe threat today for all species, say authors of a new report on the effects of deforestation on two lemur species in Madagascar.

Climate change not the only threat to vulnerable species, habitat matters
A new analysis by an international team shows that climate change is not the only threat to endangered species.
Habitat degradation and fragmentation, overharvesting, overhunting, invasive species and pollution
also play a role [Credit: Andrea Baden/Hunter College]
Writing in the current issue of Nature Climate Change, Toni Lyn Morelli at the U.S. Geological Survey's Northeast Climate Adaptation Science Center at University of Massachusetts Amherst and her international team of co-authors point out that species across the globe now face concurrent pressures on many fronts. These include habitat degradation and fragmentation, overharvesting, overhunting, invasive species and pollution in addition to climate change -- though the latter receives special attention because of its "global reach, ability to reshape entire ecosystems and potential to impact areas that are otherwise 'protected.'"

To understand these threats, they modeled the effects of deforestation and climate change on the two critically endangered ruffed lemur species in the genus Varecia over the next century. "Because of their essential role as some of Madagascar's last large-bodied seed dispersers and their sensitivity to habitat loss, ruffed lemurs serve as critical indicators of rainforest health," says co-author Andrea Baden of Hunter College CUNY, New York. "Ruffed lemurs and rainforests rely on each other. Remove one and the system collapses."

Undertaking what Morelli calls "a massive effort," she and her 21 colleagues combined 88 years of data to report on how deforestation will affect ruffed lemurs. Morelli, who did her doctoral work in Madagascar, says team members conducted research at thousands of sites on this island off the southeast coast of Africa with a wide range of government, foundation and academic support.

They estimate that suitable rainforest habitat could be reduced by as much as 59 % from deforestation, as much as 75 % from climate change alone, and almost entirely lost from both before 2080. Thus, protecting protected areas is a key conservation strategy, research ecologist Morelli says. She and co-authors write, "Maintaining and enhancing the integrity of protected areas, where rates of forest loss are lower, will be essential for ensuring persistence of the diversity of the rapidly-diminishing Malagasy rainforests."

Morelli adds, "Madagascar is facing devastating rates of forest loss, and lemurs are only found there and nowhere else. At this rate, even without climate change we're going to lose the rainforest and its lemurs, but with climate change we'll lose them even faster. If we can slow the deforestation, we can save some of them. Not all of them, but some of them."

Morelli adds, "This is not just about Madagascar, though it's a really special place, recognized as one of the world's biodiversity hotspots, and people really care about it. But there is a broader message. This research reminds us that there are other threats to biodiversity. We show that deforestation continues to be an imminent threat to conservation."

Baden says that the problem is not that people have not been trying to preserve habitat to save the lemurs. "There are already protected areas," she says. "If we want to save habitat and species, in the face of climate change, we have to do a better job of enforcement. But even with well-enforced protected areas, the outlook is pretty grim." The authors also discuss the likelihood that climate change will alter local residents' ability to grow and gather food, perhaps forcing further encroachment on protected lands.

Overall, "We challenge the conservation community to contemplate what should be done if nearly all of Madagascar's rainforest habitat were to be lost," they write. "To date, most conservation on the island has focused on establishment of protected areas, but even these are being eroded, albeit at a slower rate. If protected areas are not able to serve their intended purpose, how can we ensure that the perpetuation of the richness of Madagascar's biodiversity?"

Source: University of Massachusetts Amherst [December 23, 2019]

* This article was originally published here

Balblair Bronze Age Cist Stone, Inverness Museum and Gallery, Inverness, Scotland, 21.12.19.This...

Balblair Bronze Age Cist Stone, Inverness Museum and Gallery, Inverness, Scotland, 21.12.19.

This slab may have been a decorated standing stone before becoming a lid for a cist cairn. The decorative marks on its surface are unique.

* This article was originally published here

Geoscientists document 300 million year old atmospheric dust

Dust plays a crucial role in the life and health of our planet. In our modern world, dust-borne nutrients traveling in great dust storms from the Saharan Desert fertilize the soil in the Amazon Rainforest and feed photosynthetic organisms like algae in the Atlantic Ocean. In turn, it is those organisms that breathe in carbon dioxide and expel oxygen.

Geoscientists document 300 million year old atmospheric dust
This specimen of rock consists almost entirely of fossilized cyanobacteria that once lived in an ancient shallow sea.
Their proliferation decreased the amount of carbon dioxide in the atmosphere but also outcompeted
other life in ancient oceans [Credit: University of Oklahoma]
Mehrdad Sardar Abadi, a researcher in the Mewbourne College of Earth and Energy School of Geosciences and School director Lynn Soreghan, led a study with researchers from Florida State University, the Massachusetts Institute of Technology, Hampton University and the College of Charleston, to understand the role of dust on the Earth's atmosphere in deep time - 300 million years ago.

To do this research, the team needed to find ancient atmospheric dust, which led them to the remnants of a shallow marine ecosystem in modern-day Iran.

Similar to areas of our modern world like the Bahamas, these shallow marine ecosystems cannot survive unless they are in pristine water away from river runoff, Sardar Abadi explained. By targeting the systems, Sardar Abadi and Soreghan knew that silicate particles they found would have been deposited through the air and not from a river.

Sardar Abadi and Soreghan identified and sampled dust trapped in carbonate rocks from two intervals of limestone now preserved in outcroppings in the mountains of northern and central Iran.

Rocks were then subjected to a series of chemical treatments to extract the ancient dust. What was left were silicate minerals like clay and quartz that entered the environment as air-borne particles - 300-million-year-old dust.

Ancient dust in hand, Sardar Abadi could determine how much dust was in the Late Paleozoic atmosphere. Their results suggested that Earth's atmosphere was much dustier during this ancient time. Working with collaborators at Florida State University, he performed geochemical tests to analyze the iron in the samples. Those tests revealed that the ancient dust also contained remarkable proportions of highly reactive iron -- a particularly rich source of this key micronutrient.

While iron is not the only micronutrient potentially carried in dust, it is estimated that this ancient dust contained twice the bioavailable iron as the modern dust that fertilizes the Amazon Rainforest.

This potent dust fertilization led to a massive surge in marine photosynthesizers. Fueled by iron-rich dust, algae and cyanobacteria took in carbon dioxide and expelled oxygen. Researchers speculate that this action, operating over millions of years, changed the planet's atmosphere.

"Higher abundances in primary producers like plants and algae could lead to higher carbon capture, helping to explain declines in atmospheric carbon dioxide around 300 million years ago," said Sardar Abadi.

"If what we are seeing from our samples was happening on a global scale, it means that the dust fertilization effect brought down atmospheric carbon dioxide and was a fairly significant part of the carbon cycle during this time in the Earth's history," said Soreghan.

One carbon sequestration method scientists have proposed is adding bioavailable iron to isolated parts of the ocean that are so remote and far from dust-containing continents, they are essentially deserts. Scientists who have attempted this on a small scale have documented resultant phytoplankton blooms.

But, Soreghan warned, no one knows the unintended consequences of doing this on a large scale. This is why Sardar Abadi and the team of researchers delved into deep time for answers.

"The Earth's geologic record is like a laboratory book. It has run an infinite number of experiments. We can open Earth's lab book, reconstruct what happened in the past and see how the Earth responded to these sometimes very extreme states," said Soreghan.

The data and syntheses help constrain and refine computer climate models. The further back into deep time a modeler goes, the more unconstrained variables there are. By providing data, models can be more accurate.

"By delving back in time, we can uncover the most extreme states the Earth and atmosphere have experienced," said Soreghan. "That information can potentially help us solve problems today."

The team's research was recently published in the Geological Survey of America's journal, Geology.

Source: University Of Oklahoma [December 23, 2019]

* This article was originally published here

Tealing Prehistoric Earth House, Tealing, Angus, Scotland, 22.12.19.

Tealing Prehistoric Earth House, Tealing, Angus, Scotland, 22.12.19.

* This article was originally published here

Chimpanzees more likely to share tools, teach skills when task is complex

Teach a chimpanzee to fish for insects to eat, and you feed her for a lifetime. Teach her a better way to use tools in gathering prey, and you may change the course of evolution.

Chimpanzees more likely to share tools, teach skills when task is complex
An adult female chimpanzee with her offspring fishes for termites at Gombe, Tanzania. New research from Washington
University in St. Louis finds that chimpanzees that use a multi-step process and complex tools to gather
termites are more likely to share tools with novices [Credit: Kara Walker]
For most wild chimpanzees, tool use is an important part of life -- but learning these skills is no simple feat. Wild chimpanzees transfer tools to each other, and this behavior has previously been shown to serve as a form of teaching.

A new study led by researchers at Washington University in St. Louis, the University of Miami and Franklin & Marshall College finds that chimpanzees that use a multi-step process and complex tools to gather termites are more likely to share tools with novices. The research was conducted in partnership with the Wildlife Conservation Society, Lincoln Park Zoo and the Jane Goodall Institute. The study helps illuminate chimpanzees' capacity for prosocial -- or helping -- behavior, a quality that has been recognized for its potential role in the evolution of human cultural abilities.

"Non-human primates are often thought to learn tool skills by watching others and practicing on their own, with little direct help from mothers or other expert tool users," said Stephanie Musgrave, assistant professor of anthropology at the University of Miami, and first author of the study published this week in the Proceedings of the National Academy of Sciences.

"In contrast, the results from this research indicate that social learning may vary in relation to how challenging the task is: during tasks that are more difficult, mothers can in fact play a more active role, including behaviors that function to teach."

Chimpanzees more likely to share tools, teach skills when task is complex
An infant chimpanzee fishes for termites at Gombe, Tanzania
[Credit: Kara Walker]
Beginning with Jane Goodall in the 1960s, researchers have been studying chimpanzee tool use for decades at the Gombe Stream Research Center in Tanzania. The Gombe chimpanzee study is one of the longest running studies of animal behavior in the wild. This year marks the 20-year anniversary of the study of chimpanzees in the Goualougo Triangle, Republic of Congo, where researchers have documented some of the most complex tool behaviors of chimpanzees.

The study is distinctive because it applies standardized methods to directly compare how processes of cultural transmission may differ between two populations of wild chimpanzees. In both populations, the chimpanzees use tools to target the same resource -- but the task varies in complexity.

The findings of the current study are important on a number of levels, Musgrave said. "First, chimpanzee populations may vary not only in the complexity of their tool behaviors but in the social mechanisms that support these behaviors," she said. "Second, the capacity for helping in chimpanzees may be both more robust and more flexible than previously appreciated."

Maintaining chimpanzee cultures

Among animals, chimpanzees are exceptional tool users. Different groups of chimpanzees use different types of tools -- and likewise, researchers have suggested that the teaching process might be customized to facilitate these local skills.

Chimpanzees more likely to share tools, teach skills when task is complex
An adult female chimpanzee and her infant fish for termites at Gombe, Tanzania
[Credit: Kara Walker]
In this study, researchers examined the transfer of tools between chimpanzees during termite gathering, and compared the population in the Goualougo Triangle, Republic of Congo, with the population in Gombe, Tanzania.

Termites and other insects are a valuable source of fat and protein in the diet of wild chimpanzees and also contribute important vitamins and minerals. Termites build complex nest structures that encompass a network of below-ground chambers, sometimes topped with a towering, freestanding mound reaching several meters high.

Chimpanzees in both locations use fishing-probe style tools to harvest termites, but Goualougo chimpanzees use multiple, different types of tools sequentially. They also make tools from specific plant species and customize fishing probes to improve their efficiency.

The researchers found differences in the rate, probability and types of tool transfer during termite gathering between these two populations.

Chimpanzees more likely to share tools, teach skills when task is complex
An adult female chimpanzee in the Goualougo Triangle pushes a puncturing stick into the soil to create an access
tunnel into a subterranean termite nest, while holding a fishing probe in her mouth. Her infant simultaneously
manipulates a puncturing stick [Credit: Ian Nichols/NGS]
At Goualougo, where the fishing tasks were more complex, the rate of tool transfer was three times higher than at Gombe, and Goualougo mothers were more likely to transfer a tool in response to a request. Further, mothers at Goualougo most often responded to tool requests by actively giving a tool to offspring. Such active transfers were never observed at Gombe, where mothers most often responded by refusing to transfer tools. Given that offspring in both populations made comparable requests for tools, these differences suggest that mothers at Goualougo were in fact more willing to provide tools.

"We have previously documented that tool transfers at Goualougo function as a form of teaching," said Crickette Sanz, associate professor of biological anthropology in Arts & Sciences at Washington University. "The population differences we observed in the present study suggest that teaching may be related specifically to the demands of learning to manufacture tools at Goualougo, where chimpanzees use multiple tool types, make tools from select plant species, and perform modifications that increase tool efficiency."

"An increased role for this type of social learning may thus be an important component of the transmission of complex tool traditions over generations," she said.

"While Gombe and Goualougo chimpanzees both fish for termites, we suspected that there might be differences in how this skill is acquired," said Elizabeth Lonsdorf, associate professor of psychology at Franklin & Marshall College. "But only after many years of accumulating these data were we able to rigorously quantify these differences."

"To date, prosocial helping in chimpanzees has been principally examined in captivity or using differing methods in the wild," said Stephen Ross, director of the Lester E. Fisher Center for the Study and Conservation of Apes at Lincoln Park Zoo. "This study provides novel evidence for helping behavior in wild chimpanzees and demonstrates that chimpanzees can help flexibly depending on context."

A shared capacity

Understanding how chimpanzee tool traditions are passed on over generations can provide insights into the evolutionary origins of complex cultural abilities in humans.

"Human evolution is characterized by the emergence and elaboration of complex technologies, which is often attributed to our species' aptitude for passing skills onto one another through mechanisms such as teaching and imitation. However, the evolutionary origins of these capacities remain unclear," Musgrave said.

"Our research shows that the human propensity to assist others in acquiring complex skills may build at least in part upon capacities that we share with our closest living relatives."

Conservation efforts are fundamental to this research and future studies.

"Chimpanzees and their cultures are endangered," said Emma Stokes, director of the Central Africa Program at the Wildlife Conservation Society.

"Recent research shows that human activity imperils the survival of chimpanzee cultures. Studying our closest living relatives offers a unique opportunity to gain insights into the evolutionary origins of cultural behavior -- but this privilege depends on long-term efforts to conserve these apes and their habitats."

Author: Talia Ogliore | Source: Washington University in St. Louis [December 23, 2019]

* This article was originally published here


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