Tag: history

Posted on by

Vatican Secrets Revealed in New Book

This image has an empty alt attribute; its file name is ai-free.png

The Vatican has been trying for years to debunk the idea that its vaunted secret archives are all that secret: It has opened up the files of controversial World War II-era Pope Pius XII to scholars and changed the official name to remove the word “Secret” from its title.

But a certain aura of myth and mystery has persisted — until now.
The longtime prefect of what is now named the Vatican Apostolic Archive, Archbishop Sergio Pagano, is spilling the beans for the first time, revealing some of the secrets he has uncovered in the 45 years he has worked in one of the world’s most important, and unusual, repositories of documents.
In a new book-length interview titled “Secretum”, Pagano divulges some of the unknown, lesser-known and behind-the-scenes details of well-known sagas of the Holy See and its relations with the outside world over the past 12 centuries.
In conversations over the course of a year with Italian journalist Massimo Franco, Pagano delves into everything from Napoleon’s sacking of the archive in 1810 to the Galileo affair and the peculiar conclave — the assembly of cardinals to elect a pope — of 1922 that was financed by last-minute donations from U.S. Catholics.
“It’s the first time and it will also be the last because I’m about to leave,” Pagano, 75, said in an interview with The Associated Press in his archive office, ahead of his expected retirement later this year.
Pope Leo XIII first opened the archive to scholars in 1881, after it had been used exclusively to serve the pope and preserve documentation of the papacies, ecumenical councils and Vatican offices dating from the 8th century.
With 85 kilometers (53 miles) of shelving, much of it underground in a two-story, fireproof, reinforced concrete bunker, the archive also houses documentation from Vatican embassies around the globe as well as specific collections from aristocratic families and religious orders.
While often the source of Dan Brown-esque conspiracies, it functions much as any national or private archive: Researchers request permission to visit and then request specific documents to review in dedicated reading rooms.
Pagano keeps a close eye on them from a giant television screen perched to the side of his desk, which provides a live, closed-circuit feed to the reading rooms downstairs.
Most recently, scholars have been flocking to the archive to read through the documents of the pontificate of Pope Pius XII, the wartime pope who has been criticized for not having spoken out enough about the Holocaust.
The Vatican has long defended Pius, saying he used quiet diplomacy to save lives and didn’t speak out publicly about Nazi crimes because he feared retaliation, including against the Vatican itself. Pagano is no apologist for Pius and stands out among Vatican hierarchs for his willingness to call out Pius’ silence. Specifically, Pagano says he cannot square Pius’ continued reluctance to publicly condemn Nazi atrocities even after the war ended.


https://www.pbs.org/newshour/world/the-keeper-of-the-vaticans-secrets-is-revealing-century-old-discoveries-for-forthcoming-book

AR #79

The Lost Mind”, by Phillip Coppens

Posted on by

New Evidence for Very Early Human Migration in Eastern Asia

This image has an empty alt attribute; its file name is ai-free.png

An international team of researchers has unearthed evidence shedding new light on the ancient migration of Homo sapiens into eastern Asia around 45,000 years ago.

The findings, detailed in a study published in Nature Ecology & Evolution, uncover what is said to be a treasure trove of cultural and technological innovations in the Shiyu site in northern China, marking what is considered a significant moment in human history (https://www.nature.com/articles/s41559-023-02294-4).
According to the researchers, the Shiyu site provides a glimpse into the unique convergence of cultural behaviors and technological advancements of our ancient ancestors, and challenges conventional beliefs about the dispersal of Homo sapiens populations.
Key revelations from the research include:
Shiyu now stands as the oldest and easternmost site of its kind, showcasing Homo sapiens’ presence in eastern Asia around 45,000 years ago as demonstrated by radiocarbon and luminescence dating led by Professor Jia-Fu Zhang of Peking University. This discovery reshapes our understanding of the timing and routes of human migration in the region.
Shiyu exhibits what is described as a remarkable array of technological advancements, including stone tools crafted using Levallois and Volumetric Blade Reduction methods. Additionally, the long-distance transport of obsidian from sources hundreds of kilometers away indicates advanced resource procurement strategies.
Shiyu showcases a cultural blend characterized by a mix of Upper Palaeolithic innovations such as blade reduction and symbolic tools, Middle Palaeolithic traits such as Levallois reduction, and traditional elements of Chinese core-flake industries. The discovery of unique artifacts, such as a shaped graphite disc and bone tools, illustrates, it is claimed, a rich cultural adaptation.
The discovery, say the study authors, presented a different view of human migration and cultural evolution than previous studies of the Shiyu location.
“The Shiyu findings challenge previous notions of early human migration and cultural development in Eastern Asia,” said study author Michael Petraglia.

Picture and Captions:
https://news.griffith.edu.au/2024/01/19/shiyu-discovery-reveals-eastern-asias-early-human-migrations/

AR #21

Searching for Shambala” by Cynthia Gage

Posted on by

Archaeological Mystery Based on Forgery

This image has an empty alt attribute; its file name is ai-free.png

A 280-million-year-old fossil that has baffled researchers for decades has been shown to be, in part, a forgery following new examination of the remnants.

The discovery has led the team led by Dr Valentina Rossi of University College Cork, Ireland (UCC) to urge caution in how the fossil is used in future research.
Tridentinosaurus antiquus was discovered in the Italian alps in 1931 and was thought to be an important specimen for understanding early reptile evolution.
Its body outline, appearing dark against the surrounding rock, was initially interpreted as preserved soft tissues. This led to its classification as a member of the reptile group Protorosauria.
However, this new research, published in the scientific journal Palaeontology, reveals that the fossil renowned for its remarkable preservation is mostly just black paint on a carved lizard-shaped rock surface (https://onlinelibrary.wiley.com/doi/10.1111/pala.12690).
The purported fossilized skin had been celebrated in articles and books but never studied in detail. The somewhat strange preservation of the fossil had left many experts uncertain about what group of reptiles this strange lizard-like animal belonged to and more generally its geological history.
Dr Rossi, of UCC’s School of Biological, Earth and Environmental Sciences, said:
“Fossil soft tissues are rare, but when found in a fossil they can reveal important biological information, for instance, the external colouration, internal anatomy and physiology.
“The answer to all our questions was right in front of us, we had to study this fossil specimen in details to reveal its secrets – even those that perhaps we did not want to know”.
The microscopic analysis showed that the texture and composition of the material did not match that of genuine fossilized soft tissues.
Preliminary investigation using UV photography revealed that the entirety of the specimen was treated with some sort of coating material. Coating fossils with varnishes and/or lacquers was the norm in the past and sometimes is still necessary to preserve a fossil specimen in museum cabinets and exhibits. The team was hoping that beneath the coating layer, the original soft tissues were still in good condition to extract meaningful palaeobiological information.
The findings indicate that the body outline of Tridentinosaurus antiquus was artificially created, likely to enhance the appearance of the fossil. This deception misled previous researchers, and now caution is being urged when using this specimen in future studies.

https://www.ucc.ie/en/news/2024/mystery-solved-the-oldest-fossil-reptile-from-the-alps-is-an-historical-forgery.html

AR #125

“Jurassic Soft Tissue”

Stephen Robbins, Ph.D.

Posted on by

Earth’s Magnetic Field Confirms Old Testament Event

This image has an empty alt attribute; its file name is ai-free.png

A breakthrough achieved by researchers from four Israeli universities will enable archaeologists to identify burnt materials discovered in excavations and estimate their firing temperatures. Applying their method to findings from ancient Gath (Tell es-Safi in central Israel), the researchers validated the Biblical account: “About this time Hazael King of Aram went up and attacked Gath and captured it. Then he turned to attack Jerusalem” (2 Kings 12, 18). They explain that unlike previous methods, the new technique can determine whether a certain item (such as a mud brick) underwent a firing event even at relatively low temperatures, from 200°C and up. This information can be crucial for correctly interpreting the findings. 

The multidisciplinary study was led by Dr. Yoav Vaknin from the Sonia & Marco Nadler Institute of Archaeology, Entin Faculty of Humanities, at Tel Aviv University, and the Palaeomagnetic Laboratory at The Hebrew University. The paper has been published in the scientific journal PLOS ONE (https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0289424).
The new method relies on measuring the magnetic field recorded and ‘locked’ in the brick as it burned and cooled down. Dr. Vaknin: “The clay from which the bricks were made contains millions of ferromagnetic particles – minerals with magnetic properties that behave like so many tiny ‘compasses’ or magnets. In a sun-dried mud brick the orientation of these magnets is almost random, so that they cancel out one another. Therefore, the overall magnetic signal of the brick is weak and not uniform. Heating to 200°C or more, as happens in a fire, releases the magnetic signals of these magnetic particles and, statistically, they tend to align with the earth’s magnetic field at that specific time and place. When the brick cools down, these magnetic signals remain locked in their new position and the brick attains a strong and uniformly oriented magnetic field, which can be measured with a magnetometer. This is a clear indication that the brick has, in fact, been fired.
 In the second stage of the procedure, the researchers gradually ‘erase’ the brick’s magnetic field, using a process called thermal demagnetization. This involves heating the brick in a special oven in a palaeomagnetic laboratory that neutralizes the earth’s magnetic field. The heat releases the magnetic signals, which once again arrange themselves randomly, canceling each other out, and the total magnetic signal becomes weak and loses its orientation.
After proving the method’s validity, the researchers applied it to a specific archaeological dispute: was a specific brick structure discovered at Tell es-Safi – identified as the Philistine city of Gath, home of Goliath – built of pre-fired bricks or burned on location? The prevalent hypothesis, based on the Old Testament, historical sources, and Carbon-14 dating attributes the destruction of the structure to the devastation of Gath by Hazael, King of Aram Damascus, around 830 BCE. However, a previous paper by researchers including Prof. Maeir, head of the Tell es-Safi excavations, proposed that the building had not burned down, but rather collapsed over decades, and that the fired bricks found in the structure had been fired in a kiln prior to construction. If this hypothesis were correct, this would be the earliest instance of brick-firing technology discovered in the Land of Israel. 
 To settle the dispute, the current research team applied the new method to samples from the wall at Tell es-Safi and the collapsed debris found beside it. The findings were conclusive: the magnetic fields of all bricks and collapsed debris displayed the same orientation – north and downwards. Dr. Vaknin: “Our findings signify that the bricks burned and cooled down in-situ, right where they were found, namely in a conflagration in the structure itself, which collapsed within a few hours. Had the bricks been fired in a kiln and then laid in the wall, their magnetic orientations would have been random. Moreover, had the structure collapsed over time, not in a single fire event, the collapsed debris would have displayed random magnetic orientations. We believe that the main reason for our colleagues’ mistaken interpretation was their inability to identify burning at temperatures below 500°C. Since heat rises, materials at the bottom of the building burned at relatively low temperatures, below 400°C, and consequently the former study did not identify them as burnt – leading to the conclusion that the building had not been destroyed by fire. At the same time, bricks in upper parts of the wall, where temperatures were much higher, underwent mineralogical changes and were therefore identified as burnt – leading the researchers to conclude that they had been fired in a kiln prior to construction. Our method allowed us to determine that all bricks in both the wall and debris had burned during the conflagration: those at the bottom burned at relatively low temperatures, and those that were found in higher layers or had fallen from the top –at temperatures higher than 600°C.”
 
https://www.aftau.org/news_item/tau-researchers-use-earths-magnetic-field-to-verify-old-testament-event/

AR #61

“Gnosis and the Secrets of Solomon’s Temple”

by Philip Gardner

Posted on by

Could Oxygen Hold the Secret of Alien Technology?

This image has an empty alt attribute; its file name is ai-free.png

In the quest to understand the potential for life beyond Earth, researchers are widening their search to encompass not only biological markers, but also technological ones. While astrobiologists have long recognized the importance of oxygen for life as we know it, oxygen could also be a key to unlocking advanced technology on a planetary scale.

In a new study published in Nature Astronomy, Adam Frank, the Helen F. and Fred H. Gowen Professor of Physics and Astronomy at the University of Rochester and the author of The Little Book of Aliens (Harper, 2023), and Amedeo Balbi, an associate professor of astronomy and astrophysics at the University of Roma Tor Vergata, Italy, outline the links between atmospheric oxygen and the potential rise of advanced technology on distant planets (https://www.nature.com/articles/s41550-023-02112-8).
Frank and Balbi posit that, beyond its necessity for respiration and metabolism in multicellular organisms, oxygen is crucial to developing fire—and fire is a hallmark of a technological civilization. They delve into the concept of “technospheres,” expansive realms of advanced technology that emit telltale signs—called “technosignatures”—of extraterrestrial intelligence.
“If you don’t have oxygen in the atmosphere, you’re not going to have a technological species.”
On Earth, the development of technology demanded easy access to open-air combustion—the process at the heart of fire, in which something is burned by combining a fuel and an oxidant, usually oxygen. Whether it’s cooking, forging metals for structures, crafting materials for homes, or harnessing energy through burning fuels, combustion has been the driving force behind industrial societies.
Tracing back through Earth’s history, the researchers found that the controlled use of fire and the subsequent metallurgical advancements were only possible when oxygen levels in the atmosphere reached or exceeded 18 percent. This means that only planets with significant oxygen concentrations will be capable of developing advanced technospheres, and, therefore, leaving detectable technosignatures.
The levels of oxygen required to biologically sustain complex life and intelligence are not as high as the levels necessary for technology, so while a species might be able to emerge in a world without oxygen, it will not be able to become a technological species, according to the researchers.
“You might be able to get biology—you might even be able to get intelligent creatures—in a world that doesn’t have oxygen,” Frank says, “but without a ready source of fire, you’re never going to develop higher technology because higher technology requires fuel and melting.”
Enter the “oxygen bottleneck,” a term coined by the researchers to describe the critical threshold that separates worlds capable of fostering technological civilizations from those that fall short. That is, oxygen levels are a bottleneck that impedes the emergence of advanced technology.
“The presence of high degrees of oxygen in the atmosphere is like a bottleneck you have to get through in order to have a technological species,” Frank says. “You can have everything else work out, but if you don’t have oxygen in the atmosphere, you’re not going to have a technological species.”
Targeting extraterrestrial hotspots
The research, which addresses a previously unexplored facet in the cosmic pursuit of intelligent life, underscores the need to prioritize planets with high oxygen levels when searching for extraterrestrial technosignatures.
“Targeting planets with high oxygen levels should be prioritized because the presence or absence of high oxygen levels in exoplanet atmospheres could be a major clue in finding potential technosignatures,” Frank says.
“The implications of discovering intelligent, technological life on another planet would be huge,” adds Balbi. “Therefore, we need to be extremely cautious in interpreting possible detections. Our study suggests that we should be skeptical of potential technosignatures from a planet with insufficient atmospheric oxygen.”
This work was funded in part by a grant from NASA.

https://www.nature.com/articles/s41550-023-02112-8

AR #62

“Fire from Water”

by John Kettler

Posted on by

Brains and the Daydream Factor?

By Catherine Caruso

This image has an empty alt attribute; its file name is ai-free.png

You are sitting quietly, and suddenly your brain tunes out the world and wanders to something else entirely — perhaps a recent experience, or an old memory. You just had a daydream.

Yet despite the ubiquity of this experience, what is happening in the brain while daydreaming is a question that has largely eluded neuroscientists.
Now, a study in mice, published Dec. 13 in Nature, has possibly brought a team led by researchers at Harvard Medical School one step closer to figuring it out (https://www.nature.com/articles/s41586-023-06810-1).
The researchers tracked the activity of neurons in the visual cortex of the brains of mice while the animals remained in a quiet waking state. They found that occasionally these neurons fired in a pattern similar to one that occurred when a mouse looked at an actual image, suggesting that the mouse was thinking — or daydreaming — about the image. Moreover, the patterns of activity during a mouse’s first few daydreams of the day predicted how the brain’s response to the image would change over time.
The research provides tantalizing, if preliminary, evidence that daydreams can shape the brain’s future response to what it sees. This causal relationship needs to be confirmed in further research, the team cautioned, but the results offer an intriguing clue that daydreams during quiet waking may play a role in brain plasticity — the brain’s ability to remodel itself in response to new experiences.
“We wanted to know how this daydreaming process occurred on a neurobiological level, and whether these moments of quiet reflection could be important for learning and memory,” said lead author Nghia Nguyen, a PhD student in neurobiology in the Blavatnik Institute at HMS.
Scientists have spent considerable time studying how neurons replay past events to form memories and map the physical environment in the hippocampus, a seahorse-shaped brain region that plays a key role in memory and spatial navigation.
By contrast, there has been little research on the replay of neurons in other brain regions, including the visual cortex. Such efforts would provide valuable insights about how visual memories are formed.
In the new study, the researchers repeatedly showed mice one of two images, each consisting of a different checkerboard pattern of gray and dappled black and white squares. Between images, the mice spent a minute looking at a gray screen. The team simultaneously recorded activity from around 7,000 neurons in the visual cortex.
The researchers found that when a mouse looked at an image, the neurons fired in a specific pattern, and the patterns were different enough to discern image one from image two. More important, when a mouse looked at the gray screen between images, the neurons sometimes fired in a similar, but not identical, pattern, as when the mouse looked at the image, a sign that it was daydreaming about the image. These daydreams occurred only when mice were relaxed, characterized by calm behavior and small pupils.
Unsurprisingly, mice daydreamed more about the most recent image — and they had more daydreams at the beginning of the day than at the end, when they had already seen each image dozens of times.
Throughout the day, and across days, the activity patterns seen when the mice looked at the images changed — what neuroscientists call “representational drift.” Yet this drift wasn’t random. Over time, the patterns associated with the images became even more different from each other, until each involved an almost entirely separate set of neurons. Notably, the pattern seen during a mouse’s first few daydreams about an image predicted what the pattern would become when the mouse looked at the image later.

AR #76

Deathbed Visitations

by Michael Tymn

Posted on by

Cognitive strategies to augment body with robotic arm

Alain Herzog CC-BY-SA

This image has an empty alt attribute; its file name is ai-free.png

EPFL scientists show that breathing may be used to control a wearable extra robotic arm in healthy individuals, without hindering control of other parts of the body.

Neuroengineer Silvestro Micera develops advanced technological solutions to help people regain sensory and motor functions that have been lost due to traumatic events or neurological disorders. Until now, he had never before worked on enhancing the human body and cognition with the help of technology.
Now in a study published in Science Robotics, Micera and his team report on how diaphragm movement can be monitored for successful control of an extra arm, essentially augmenting a healthy individual with a third – robotic – arm.
“This study opens up new and exciting opportunities, showing that extra arms can be extensively controlled and that simultaneous control with both natural arms is possible,” says Micera, Bertarelli Foundation Chair in Translational Neuroengineering at EPFL, and professor of Bioelectronics at Scuola Superiore Sant’Anna.
The study is part of the Third-Arm project, previously funded by the Swiss National Science Foundation (NCCR Robotics), that aims to provide a wearable robotic arm to assist in daily tasks or to help in search and rescue. Micera believes that exploring the cognitive limitations of third-arm control may actually provide gateways towards better understanding of the human brain.
Micera continues, “The main motivation of this third arm control is to understand the nervous system. If you challenge the brain to do something that is completely new, you can learn if the brain has the capacity to do it and if it’s possible to facilitate this learning. We can then transfer this knowledge to develop, for example, assistive devices for people with disabilities, or rehabilitation protocols after stroke.”

“We want to understand if our brains are hardwired to control what nature has given us, and we’ve shown that the human brain can adapt to coordinate new limbs in tandem with our biological ones,” explains Solaiman Shokur, co-PI of the study and EPFL Senior Scientist at the Neuro-X Institute. “It’s about acquiring new motor functions, enhancement beyond the existing functions of a given user, be it a healthy individual or a disabled one. From a nervous system perspective, it’s a continuum between rehabilitation and augmentation.”
To explore the cognitive constraints of augmentation, the researchers first built a virtual environment to test a healthy user’s capacity to control a virtual arm using movement of his or her diaphragm. They found that diaphragm control does not interfere with actions like controlling one’s physiological arms, one’s speech or gaze.
In this virtual reality setup, the user is equipped with a belt that measures diaphragm movement. Wearing a virtual reality headset, the user sees three arms: the right arm and hand, the left arm and hand, and a third arm between the two with a symmetric, six-fingered hand.
“We made this hand symmetric to avoid any bias towards either the left or the right hand,” explains Giulia Dominijanni, PhD student at EPFL’s Neuro-X Institute.
In the virtual environment, the user is then prompted to reach out with either the left hand, the right hand, or in the middle with the symmetric hand. In the real environment, the user holds onto an exoskeleton with both arms, which allows for control of the virtual left and right arms. Movement detected by the belt around the diaphragm is used for controlling the virtual middle, symmetric arm. The setup was tested on 61 healthy subjects in over 150 sessions.
“Diaphragm control of the third arm is actually very intuitive, with participants learning to control the extra limb very quickly,” explains Dominijanni. “Moreover, our control strategy is inherently independent from the biological limbs and we show that diaphragm control does not impact a user’s ability to speak coherently.”
The researchers also successfully tested diaphragm control with an actual robotic arm, a simplified one that consists of a rod that can be extended out, and back in. When the user contracts the diaphragm, the rod is extended out. In an experiment similar to the VR environment, the user is asked to reach and hover over target circles with her left or right hand, or with the robotic rod.
Besides the diaphragm, but not reported in the study, vestigial ear muscles have also been tested for feasibility in performing new tasks. In this approach, a user is equipped with ear sensors and trained to use fine ear muscle movement to control the displacement of a computer mouse.
“Users could potentially use these ear muscles to control an extra limb,” says Shokur, emphasizing that these alternative control strategies may help one day for the development of rehabilitation protocols for people with motor deficiencies.
Part of the third arm project, previous studies regarding the control of robotic arms have been focused on helping amputees. The latest Science Robotics study is a step beyond repairing the human body towards augmentation.
“Our next step is to explore the use of more complex robotic devices using our various control strategies, to perform real-life tasks, both inside and outside of the laboratory. Only then will we be able to grasp the real potential of this approach,” concludes Micera.

AR #84

Molecular Machines that Defy Darwin

by Casey Luskin

Posted on by

Finnish team found out the composition of asteroid Phaethon

This image has an empty alt attribute; its file name is ai-free.png

The asteroid that causes the Geminid shooting star swarm has also puzzled researchers with its comet-like tail. The infrared spectrum of rare meteorites helped to determine the composition of the asteroid.

Postdoctoral Researcher Eric MacLennan holds in his hands a very rare type of meteorite, the so-called CY carbonaceous chondrite. Only six specimens of the same type are known. The sample is on loan from the Natural History Museum in London. (Image: Susan Heikkinen)
Asteroid Phaethon, which is five kilometers in diameter, has been puzzling researchers for a long time. A comet-like tail is visible for a few days when the asteroid passes closest to the Sun during its orbit.
However, the tails of comets are usually formed by vaporizing ice and carbon dioxide, which cannot explain this tail. The tail should be visible already at Jupiter’s distance from the Sun.
When the surface layer of an asteroid breaks up, the detached gravel and dust continue to travel in the same orbit and give birth to a cluster of shooting stars when it encounters the Earth. Phaethon causes the Geminid meteor shower, which also appears in the skies of Finland every year around mid-December. At least according to the prevailing hypothesis because that’s when the Earth crosses the asteroid’s path.
Until now, theories about what happens on Phaethon’s surface near the Sun have remained purely hypothetical. What comes off the asteroid? How? The answer to the riddle was found by understanding the composition of Phaethon.
A rare meteorite group consisting of six known meteorites
In a recent study published in the journal Nature Astronomy by researchers from the University of Helsinki, the infrared spectrum of Phaethon previously measured by NASA’s Spitzer space telescope is re-analyzed and compared to infrared spectra of meteorites measured in laboratories.
The researchers found that Phaethon’s spectrum corresponds exactly to a certain type of meteorite, the so-called CY carbonaceous chondrite. It is a very rare type of meteorite, of which only six specimens are known.
Asteroids can also be studied by retrieving samples from space, but meteorites can be studied without expensive space missions. Asteroids Ryugu and Bennu, the targets of recent JAXA and NASA sample-return missions, belong to CI and CM meteorites.
All three types of meteorites originate from the birth of the Solar System, and partially resemble each other, but only the CY group shows signs of drying and thermal decomposition due to recent heating.
All three groups show signs of a change that occurred during the early evolution of the Solar System, where water combines with other molecules to form phyllosilicate and carbonate minerals. However, CY-type meteorites differ from others due to their high iron sulfide content, which suggests their own origin.
Phaethon’s spectrum match the spectra of CY carbonaceous chondrites
Analysis of Phaethon’s infrared spectrum showed that the asteroid was composed of at least olivine, carbonates, iron sulfides, and oxide minerals. All of these minerals supported the connection to the CY meteorites, especially iron sulfide. The carbonates suggested changes in water content that fit the primitive composition, while the olivine is a product of thermal decomposition of phyllosilicates at extreme temperatures.
In the research, it was possible to show with thermal modeling what temperatures prevail on the surface of the asteroid and when certain minerals break down and release gases. When Phaethon passes close to the Sun, its surface temperature rises to about 800°C. The CY meteorite group fits this well. At similar temperatures, carbonates produce carbon dioxide, phyllosilicates release water vapor and sulfides sulfur gas.
According to the study, all the minerals identified on Phaethon appear to correspond to the minerals of CY-type meteorites. The only exceptions were the oxides portlandite and brucite, which were not detected in the meteorites. However, these minerals can form when carbonates are heated and destroyed in the presence of water vapor.
The tail and the meteor shower get an explanation
Asteroid composition and temperature explained the formation of gas near the Sun, but do they also explain the dust and gravel forming the Geminid meteors? Did the asteroid have enough pressure to lift dust and rock from the surface of the asteroid?
The researchers used experimental data from other studies in conjunction with their thermal models, and, based on them, it was estimated that when the asteroid passes closest to the Sun, gas is released from the mineral structure of the asteroid, which can cause the rock to break down. In addition, the pressure produces by carbon dioxide and water vapor is high enough to lift small dust particles from the surface of the asteroid.
“Sodium emission can explain the weak tail we observe near the Sun, and thermal decomposition can explain how dust and gravel are released from Phaethon,” says the study’s lead author, postdoctoral researcher Eric MacLennan from the University of Helsinki.
“It was great to see how each one of the discovered minerals seemed to fall into place and also explain the behavior of the asteroid,” sums up associate professor Mikael Granvik from the University of Helsinki.

AR #87

Russians Warn of Asteroid Hit in 2036

Posted on by

Neanderthals Genes from ‘Cousins’ of Modern Humans Found

This image has an empty alt attribute; its file name is ai-free.png

Modern humans migrated to Eurasia 75,000 years ago, where they encountered and interbred with Neanderthals. A new study published in the journal Current Biology shows that at this time Neanderthals were already carrying human DNA from a much older encounter with modern humans. A new study shows that an ancient lineage of modern humans migrated to Eurasia over 250,000 years ago where they interbred with Neanderthals. Over time, these humans died out, leaving a population with predominantly Neanderthal ancestry ( https://www.cell.com/current-biology/fulltext/S0960-9822(23)01315-5 )

“We found this reflection of ancient interbreeding where genes flowed from ancient modern humans into Neanderthals,” says Alexander Platt, a senior research scientist in the Perelman School of Medicine and one of the study’s first authors. “This group of individuals left Africa between 250,000 and 270,000 years ago. They were sort of the cousins to all humans alive today, and they were much more like us than Neanderthals.”
Because most Neanderthal-human interbreeding is thought to have occurred in Eurasia, not in Africa, Neanderthal ancestry is expected to be limited in sub-Saharan Africa; however, a recent study made the puzzling observation that several sub-Saharan populations contain chunks of DNA that resemble Neanderthal DNA. The study was unable to determine how this Neanderthal-like DNA entered these populations, whether it originated from modern humans who had migrated from Africa, interbred with Neanderthals in Eurasia, and then returned, or whether it was the result of an earlier encounter between Neanderthals and humans. Because the study relied on a limited number of genomes from the 1,000 Genomes Project, all of which share a relatively recent common ancestry in Central and Western Africa, it was also unclear whether Neanderthal-like DNA is widespread among sub-Saharan populations.
To better understand how widespread these Neanderthal-like DNA regions are across sub-Saharan Africa and to elucidate their origins, Tishkoff’s team leveraged a genetically diverse set of genomes of 180 individuals from 12 different populations in Cameroon, Botswana, Tanzania, and Ethiopia. For each genome, the researchers identified regions of Neanderthal-like DNA and looked for evidence of Neanderthal ancestry.
Then, they compared the modern human genomes to a genome belonging to a Neanderthal who lived approximately 120,000 years ago. For this comparison, the team developed a novel statistical method that allowed them to determine the origins of the Neanderthal-like DNA in these modern sub-Saharan populations, whether they were regions that Neanderthals inherited from modern humans or regions that modern humans inherited from Neanderthals and then brought back to Africa.
They found that all of the sub-Saharan populations contained Neanderthal-like DNA, indicating that this phenomenon is widespread. In most cases, this Neanderthal-like DNA originated from an ancient lineage of modern humans that passed their DNA on to Neanderthals when they migrated from Africa to Eurasia around 250,000 years ago. As a result of this modern human-Neanderthal interbreeding, approximately 6% of the Neanderthal genome was inherited from modern humans.
In some specific sub-Saharan populations, the researchers also found evidence of Neanderthal ancestry that was introduced to these populations when humans bearing Neanderthal genes migrated back into Africa. Neanderthal ancestry in these sub-Saharan populations ranged from 0 to 1.5%, and the highest levels were observed in the Amhara from Ethiopia and Fulani from Cameroon.
To try to understand whether carrying modern human DNA was helpful or harmful when introduced into the Neanderthal genome, the researchers also investigated where these chunks of modern human DNA were located. To try to understand whether carrying modern human DNA was helpful or harmful, the researchers also investigated where these chunks of modern human DNA were located within the Neanderthal genome. They found that most of the modern human DNA was in noncoding regions of the Neanderthal genome, indicating that modern human gene variants were being preferentially lost from coding sections of the genome, which suggests that having modern human genes in a Neanderthal background is detrimental to fitness. 

AR #81

The Fate of the Watchers

by Andrew Collins

Posted on by

Pliosaur Carcass, the Oldest Sea Monster Yet Found

This image has an empty alt attribute; its file name is ai-free.png

The fossils of a 170-million-year-old ancient marine reptile from the Age of Dinosaurs have been identified as the oldest-known mega-predatory pliosaur – a group of ocean-dwelling reptiles closely related to the famous long-necked plesiosaurs. The findings are rare and add new knowledge to the evolution of plesiosaurs. The study has been published in the journal Scientific Reports (https://www.nature.com/articles/s41598-023-43015-y).

The fossils were found 40 years ago in north-eastern France. An international team of palaeontologists have now analized them and identified them as a new pliosaur genus: Lorrainosaurus.
Pliosaurs were a type of plesiosaur with short necks and massive skulls. They appeared over 200 million years ago, but remained minor components of marine ecosystems until suddenly developing into enormous apex predators. The new study shows that this adaptive shift followed feeding niche differentiation and the global decline of other predatory marine reptiles over 170 million years ago.
Lorrainosaurus is the oldest large-bodied pliosaur represented by an associated skeleton. It had jaws over 1.3 m long with large conical teeth and a bulky ‘torpedo-shaped’ body propelled by four flipper-like limbs.
“Lorrainosaurus was one of the first truly huge pliosaurs. It gave rise to a dynasty of marine reptile mega-predators that ruled the oceans for around 80 million years,” explains Sven Sachs, a researcher at the Naturkunde-Museum Bielefeld, who led the study.
This giant reptile probably reached over 6 m from snout to tail, and lived during the early Middle Jurassic period. Intriguingly, very little is known about plesiosaurs from that time.
“Our identification of Lorrainosaurus as one of the earliest mega-predatory pliosaurs demonstrates that these creatures emerged immediately after a landmark restructuring of marine predator ecosystems across the Early-to-Middle Jurassic boundary, some 175 to 171 million years ago. This event profoundly affected many marine reptile groups and brought mega-predatory pliosaurids to dominance over ‘fish-like’ ichthyosaurs, ancient marine crocodile relatives, and other large-bodied predatory plesiosaurs”, adds Daniel Madzia from the Institute of Paleobiology of the Polish Academy of Sciences, who co-led the study.
Pliosaurs were some of the most successful marine predators of their time. “Famous examples, such as Pliosaurus and Kronosaurus – some of the world’s largest pliosaurs – were absolutely enormous with body-lengths exceeding 10 m. They were ecological equivalents of today’s Killer whales and would have eaten a range of prey including squid-like cephalopods, large fish and other marine reptiles. These have all been found as preserved gut contents”, said senior co-author Benjamin Kear, Curator of Vertebrate Palaeontology and Researcher in Palaeontology at The Museum of Evolution, Uppsala University.
The recovered bones and teeth of Lorrainosaurus represent remnants of what was once a complete skeleton that decomposed and was dispersed across the ancient sea floor by currents and scavengers.
“The remains were unearthed in 1983 from a road cutting near Metz in Lorraine, north-eastern France. Palaeontology enthusiasts from the Association minéralogique et paléontologique d’Hayange et des environs recognised the significance of their discovery and donated the fossils to the Natural History Museum in Luxembourg”, said co-author Ben Thuy, Curator at the Natural History Museum in Luxembourg.

AR #119

The Dragon Factor

by William B. Stoecker