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Scientists have developed a low-cost, durable, highly-sensitive robotic 'skin' that can be added to robotic hands like a glove, enabling robots to detect information about their surroundings in a way that's similar to humans.

The researchers, from the University of Cambridge and University College London (UCL), developed the flexible, conductive skin, which is easy to fabricate and can be melted down and formed into a wide range of complex shapes. The technology senses and processes a range of physical inputs, allowing robots to interact with the physical world in a more meaningful way.

Unlike other solutions for robotic touch, which typically work via sensors embedded in small areas and require different sensors to detect different types of touch, the entirety of the electronic skin developed by the Cambridge and UCL researchers is a sensor, bringing it closer to our own sensor system: our skin.

Although the robotic skin is not as sensitive as human skin, it can detect signals from over 860,000 tiny pathways in the material, enabling it to recognise different types of touch and pressure – like the tap of a finger, a hot or cold surface, damage caused by cutting or stabbing, or multiple points being touched at once – in a single material.

The researchers used a combination of physical tests and machine learning techniques to help the robotic skin 'learn' which of these pathways matter most, so it can sense different types of contact more efficiently.

In addition to potential future applications for humanoid robots or human prosthetics where a sense of touch is vital, the researchers say the robotic skin could be useful in industries as varied as the automotive sector or disaster relief. The results are reported in the journalScience Robotics.

Electronic skins work by converting physical information – like pressure or temperature – into electronic signals. In most cases, different types of sensors are needed for different types of touch – one type of sensor to detect pressure, another for temperature, and so on – which are then embedded into soft, flexible materials. However, the signals from these different sensors can interfere with each other, and the materials are easily damaged.

"Having different sensors for different types of touch leads to materials that are complex to make," said lead author Dr David Hardman from Cambridge's Department of Engineering. "We wanted to develop a solution that can detect multiple types of touch at once, but in a single material."

"At the same time, we need something that's cheap and durable, so that it's suitable for widespread use," said co-author Dr Thomas George Thuruthel from UCL.

Their solution uses one type of sensor that reacts differently to different types of touch, known as multi-modal sensing. While it's challenging to separate out the cause of each signal, multi-modal sensing materials are easier to make and more robust.

The researchers melted down a soft, stretchy and electrically conductive gelatine-based hydrogel, and cast it into the shape of a human hand. They tested a range of different electrode configurations to determine which gave them the most useful information about different types of touch. From just 32 electrodes placed at the wrist, they were able to collect over 1.7 million pieces of information over the whole hand, thanks to the tiny pathways in the conductive material.

The skin was then tested on different types of touch: the researchers blasted it with a heat gun, pressed it with their fingers and a robotic arm, gently touched it with their fingers, and even cut it open with a scalpel. The team then used the data gathered during these tests to train a machine learning model so the hand would recognize what the different types of touch meant.

"We're able to squeeze a lot of information from these materials – they can take thousands of measurements very quickly," said Hardman, who is a postdoctoral researcher in the lab of co-author Professor Fumiya Iida. "They're measuring lots of different things at once, over a large surface area."

"We're not quite at the level where the robotic skin is as good as human skin, but we think it's better than anything else out there at the moment," said Thuruthel. "Our method is flexible and easier to build than traditional sensors, and we're able to calibrate it using human touch for a range of tasks."

In future, the researchers are hoping to improve the durability of the electronic skin, and to carry out further tests on real-world robotic tasks.

The research was supported by Samsung Global Research Outreach Program, the Royal Society, and the Engineering and Physical Sciences Research Council (EPSRC), part of UK Research and Innovation (UKRI). Fumiya Iida is a Fellow of Corpus Christi College, Cambridge.

Materialsprovided byUniversity of Cambridge.Note: Content may be edited for style and length.

While you're probably not pouring your morning cup for the long-term health benefits, coffee consumption has been linked to lower risk of mortality. In a new observational study, researchers from the Gerald J. and Dorothy R. Friedman School of Nutrition Science and Policy at Tufts University found the association between coffee consumption and mortality risk changes with the amount of sweeteners and saturated fat added to the beverage.

The study, published online inThe Journal of Nutrition, found that consumption of 1-2 cups of caffeinated coffee per day was linked to a lower risk of death from all causes and death from cardiovascular disease. Black coffee and coffee with low levels of added sugar and saturated fat were associated with a 14% lower risk of all-cause mortality as compared to no coffee consumption. The same link was not observed for coffee with high amounts of added sugar and saturated fat.

"Coffee is among the most-consumed beverages in the world, and with nearly half of American adults reporting drinking at least one cup per day, it's important for us to know what it might mean for health," said Fang Fang Zhang, senior author of the study and the Neely Family Professor at the Friedman School. "The health benefits of coffee might be attributable to its bioactive compounds, but our results suggest that the addition of sugar and saturated fat may reduce the mortality benefits."

The study analyzed data from nine consecutive cycles of the National Health and Nutrition Examination Survey (NHANES) from 1999 to 2018, linked to National Death Index Mortality Data. The study included a nationally representative sample of 46,000 adults aged 20 years and older who completed valid first-day 24-hour dietary recalls. Coffee consumption was categorized by type (caffeinated or decaffeinated), sugar, and saturated fat content. Mortality outcomes included all-cause, cancer, and cardiovascular disease. Low added sugar (from granulated sugar, honey, and syrup) was defined as under 5% of the Daily Value, which is 2.5 grams per 8-ounce cup or approximately half a teaspoon of sugar. Low saturated fat (from milk, cream, and half-and-half) was defined as 5% of the Daily Value, or 1 gram per 8-ounce cup or the equivalent of 5 tablespoons of 2% milk, 1 tablespoon of light cream, or 1 tablespoon of half-and-half.

In the study, consumption of at least one cup per day was associated with a 16% lower risk of all-cause mortality. At 2-3 cups per day, the link rose to 17%. Consumption beyond three cups per day was not associated with additional reductions, and the link between coffee and a lower risk of death by cardiovascular disease weakened when coffee consumption was more than three cups per day. No significant associations were seen between coffee consumption and cancer mortality.

"Few studies have examined how coffee additives could impact the link between coffee consumption and mortality risk, and our study is among the first to quantify how much sweetener and saturated fat are being added," said first author Bingjie Zhou, a recent Ph.D. graduate from the nutrition epidemiology and data science program at the Friedman School. "Our results align with the Dietary Guidelines for Americans which recommend limiting added sugar and saturated fat."

Limitations of the study include the fact that self-reported recall data is subject to measurement error due to day-to-day variations in food intake. The lack of significant associations between decaffeinated coffee and all-cause mortality could be due to the low consumption among the population studied.

Additional authors are Yongyi Pan and Lu Wang, both of the Friedman School, and Mengyuan Ruan, a graduate of the Friedman School.

The study was supported by the National Institutes of Health's National Institute on Minority Health and Health Disparities under award number R01MD011501. Complete information on methodology is available in the published paper. The content is the sole responsibility of the authors and does not necessarily represent the official views the National Institutes of Health.

Materialsprovided byTufts University.Note: Content may be edited for style and length.

Nematodes are the most abundant animal on earth, but when times get tough, these tiny worms have a hard time moving up and out. So, they play to the strength of their clade. If food runs out and competition turns fierce, they slither towards their numerous kin. They climb onto each other and over one another until their bodies forge a living tower that twists skyward where they might hitch a ride on a passing animal to greener and roomier pastures.

At least that's what scientists assumed. For decades, these worm structures were more mythical than material. Such aggregations, in which animals link bodies for group movement, are rare in nature. Only slime molds, fire ants, and spider mites are known to move in this way. For nematodes, nobody had even seen the aggregations — known as towers — forming anywhere but within the artificial confines of laboratories and growth chambers; and nobody really knew what they were for. Did towers even exist in the real world?

Now, researchers in Konstanz, Germany, have recorded video footage of worms towering in fallen apples and pears from local orchards. The team from the Max Planck Institute of Animal Behavior (MPI-AB) and the University of Konstanz combined fieldwork with laboratory experiments to provide the first direct evidence that towering behavior occurs naturally and functions as a means of collective transport.

"I was ecstatic when I saw these natural towers for the first time," says senior author Serena Ding, group leader at the MPI-AB, of the moment when co-author Ryan Greenway sent her a video recording from the field. "For so long natural worm towers existed only in our imaginations. But with the right equipment and lots of curiosity, we found them hiding in plain sight."

Greenway, a technical assistant at the MPI-AB, spent months with a digital microscope combing through decaying fruit in orchards near the university to record natural occurrences and behavior of worm towers. Some of these whole towers were brought into the lab. What was inside the towers surprised the team. Although the fruits were crawling with many species of nematodes, natural towers were made only of a single species, all at the tough larval stage known as a "dauer."

"A nematode tower is not just a pile of worms," says the first author Daniela Perez, a postdoctoral researcher at MPI-AB. "It's a coordinated structure, a superorganism in motion."

The team observed the natural dauer towers waving in unison, much like individual nematodes do by standing on their tails to latch onto a passing animal. But their new findings showed that entire worm towers could respond to touch, detach from surfaces, and collectively attach to insects such as fruit flies — hitchhiking on mass to new environments.

To probe deeper, Perez built a controlled tower using laboratory cultures ofC. elegans. When placed on food-free agar with a small vertical post — a toothbrush bristle — hungry worms began to self-assemble. Within two hours, living towers emerged, stable for over 12 hours, and capable of extending exploratory "arms" into surrounding space. Some even formed bridges across gaps to reach new surfaces.

"The towers are actively sensing and growing," says Perez. "When we touched them, they responded immediately, growing toward the stimulus and attaching to it."

This behavior, it turns out, is not restricted to the so-called "dauer" larval stage seen from the wild samples. AdultC. elegansand all larval stages in the lab also towered — an unexpected twist that suggests towering may be a more generalized strategy for group movement than previously assumed.

Yet despite the architectural complexity of these towers, the worms inside showed no obvious role differentiation. Individuals from the base and the apex were equally mobile, fertile, and strong, hinting at a form of egalitarian cooperation. But so far only, the authors point out, in the controlled conditions of the laboratory. "C. elegansis a clonal culture and so it makes sense that there is no differentiation within the tower. In natural towers, we might see separate genetic compositions and roles, which prompts fascinating questions about who cooperates and who cheats."

As researchers seek to understand how group behavior evolves — from insect swarms to bird migrations — these microscopic worm towers might rise to provide some of the answers.

"Our study opens up a whole new system for exploring how and why animals move together," says Ding who leads a research program on nematode behavior and genetics. "By harnessing the genetic tools available forC. elegans, we now have a powerful model to study the ecology and evolution of collective dispersal."

Materialsprovided byMax Planck Institute of Animal Behavior.Note: Content may be edited for style and length.

New research led by scientists at the American Museum of Natural History sheds light on the ancient origins of biofluorescence in fishes and the range of brilliant colors involved in this biological phenomenon. Detailed in two complementary studies recently published inNature CommunicationsandPLOS One, the findings suggest that biofluorescence dates back at least 112 million years and, since then, has evolved independently more than 100 times, with the majority of that activity happening among fish that live on coral reefs.

The new work also reveals that in marine fishes, biofluorescence — which occurs when an organism absorbs light, transforms it, and emits it as a different color — involves a greater variety of colors than previously reported, spanning multiple wavelengths of green, yellow, orange, and red.

"Researchers have known for a while that biofluorescence is quite widespread in marine animals, from sea turtles to corals, and especially among fishes," said Emily Carr, a Ph.D. student in the Museum's Richard Gilder Graduate School and the lead author on the two new studies. "But to really get to the root of why and how these species use this unique adaptation — whether for camouflage, predation, or reproduction — we need to understand the underlying evolutionary story as well as the scope of biofluorescence as it currently exists."

For theNature Communicationsstudy, Carr led a comprehensive survey of all known biofluorescent teleosts — a type of bony fish that make up by far the largest group of vertebrates alive today. This resulted in a list of 459 biofluorescent species, including 48 species that were previously unknown to be biofluorescent. The researchers found that biofluorescence evolved more than 100 times in marine teleosts and is estimated to date back about 112 million years, with the first instance occurring in eels.

The team also found that fish species that live in or around coral reefs evolve biofluorescence at about 10 times the rate of non-reef species, with an increase in the number of fluorescent species following the Cretaceous-Paleogene (K-Pg) extinction about 66 million years ago, when all of the non-avian dinosaurs died off.

"This trend coincides with the rise of modern coral-dominated reefs and the rapid colonization of reefs by fishes, which occurred following a significant loss of coral diversity in the K-Pg extinction," Carr said. "These correlations suggest that the emergence of modern coral reefs could have facilitated the diversification of fluorescence in reef-associated teleost fishes."

Of the 459 known biofluorescent teleosts reported in this study, the majority are associated with coral reefs.

For thePLOS Onestudy, Carr and colleagues used a specialized photography setup with ultraviolet and blue excitation lights and emission filters to look at the wavelengths of light emitted by fishes in the Museum's Ichthyology collection. Collected over the last decade and a half on Museum expeditions to the Solomon Islands, Greenland, and Thailand, the specimens in the study were previously observed fluorescing, but the full range of their biofluorescent emissions was unknown.

The new work reveals far more diversity in colors emitted by teleosts — some families of which exhibit at least six distinct fluorescent emission peaks, which correspond with wavelengths across multiple colors — than had previously been reported.

"The remarkable variation we observed across a wide array of these fluorescent fishes could mean that these animals use incredibly diverse and elaborate signaling systems based on species-specific fluorescent emission patterns," said Museum Curator John Sparks, an author on the new studies and Carr's advisor. "As these studies show, biofluorescence is both pervasive and incredibly phenotypically variable among marine fishes. What we would really like to understand better is how fluorescence functions in these highly variable marine lineages, as well as its role in diversification."

The researchers also note that the numerous wavelengths of fluorescent emissions found in this study could have implications for identifying novel fluorescent molecules, which are routinely used in biomedical applications, including fluorescence-guided disease diagnosis and therapy.

Other authors involved in this work include Rene Martin, from the Museum and the University of Nebraska-Lincoln; Mason Thurman, from Clemson University; Karly Cohen, from California State University; Jonathan Huie, from George Washington University; David Gruber, from Baruch College and The Graduate Center, City University of New York; and Tate Sparks, Rutgers University.

Research in the Solomon Islands was supported by the National Science Foundation under Grant Number DEB-1257555.

The Museum greatly acknowledges the Dalio Foundation for its generous support of the inaugural Explore21 Expedition.

The Museum's Exlopre21 initiative is generously supported by the leadership contributions of Katheryn P. and Thomas L. Kempner, Jr.

The 2019 Constantine S. Niarchos Expedition to Greenland was generously supported by the Stavros Niarchos Foundation.

Research in Thailand was funded by the Museum and the National Science Foundation Graduate Research Fellowship Program under Grant Number DEB-1938103.

Additional funding for this work was provided by the National Science Foundation under Grant Number DGE-1746914.

Materialsprovided byAmerican Museum of Natural History.Note: Content may be edited for style and length.

A USC-led research team has created a series of supercomputer-simulated twins of our Milky Way galaxy — which could help scientists unlock new answers about one of the biggest mysteries in the universe: dark matter, the invisible substance that makes up about 85% of all matter in existence.

The research was led by cosmologist Vera Gluscevic, who is an associate professor at the USC Dornsife College of Letters, Arts, and Sciences; as well as Ethan Nadler, formerly a postdoc at USC and Carnegie Observatories who is now an assistant professor at University of California, San Diego; and Andrew Benson, a staff scientist at Carnegie Observatories.

They called their simulation project "COZMIC" — short for "Cosmological Zoom-in Simulations with Initial Conditions beyond Cold Dark Matter."

Scientists have known for decades that dark matter exists — but until now, they could not study how galaxies are born and evolve in a universe where dark and normal matter interact. COZMIC has made that possible, the team said.

The development of COZMIC and the team's results are described in a trio of studies published on June 16 in The Astrophysical Journal, a publication of the American Astronomical Society.

Scientists know that dark matter is real because it affects how galaxies move and stick together. For example, galaxies spin so fast that they should fly apart, but they don't. Something invisible holds them together; many scientists believe that dark matter is at the heart of this — an idea first suggested in 1933 by a Swiss researcher, Fritz Zwicky. Research on dark matter has evolved ever since.

Dark matter is tricky to study because it doesn't emit any light or energy that can be easily detected. Scientists study dark matter by watching how it affects motions and structures like galaxies. However, that is somewhat like studying someone's shadow without being able to examine in detail the actual person who cast the shadow.

For the suite of studies, the research team took the step of deploying new physics — not just standard particle physics and relativity — and programmed a supercomputer to create very detailed cosmological simulations through COZMIC to test different ideas about what dark matter might be doing.

"We want to measure the masses and other quantum properties of these particles, and we want to measure how they interact with everything else," Gluscevic said. "With COZMIC, for the first time, we're able to simulate galaxies like our own under radically different physical laws — and test those laws against real astronomical observations."

In addition to Glusevic, Nadler and Benson, the team behind COZMIC includes Hai-Bo Yu of UC Riverside; Daneng Yang, formerly of UC Riverside and now at Purple Mountain Observatory CAS; Xiaolong Du of UCLA; and Rui An, formerly of USC.

"Our simulations reveal that observations of the smallest galaxies can be used to distinguish dark matter models," said Nadler.

For the studies with COZMIC, the scientists accounted for the following dark matter behavior scenarios:

While running these simulations, the scientists input new physics into the supercomputer to produce a galaxy whose structure bears the signatures of those interactions between normal and dark matter, said Benson.

Gluscevic added: "While many previous simulation suites have explored the effects of dark matter mass or self-interactions, until now, none have simulated dark matter interactions with normal matter. Such interactions are not exotic or implausible. They are, in fact, likely to exist."

The team says it is a big step forward in figuring out what dark matter really is. They hope that by comparing their twin galaxies to real telescope images, they can get even closer to solving one of space's biggest mysteries.

"We're finally able to ask, 'Which version of the universe looks most like ours?'" Gluscevic said.

The COZMIC team plans to expand their work by directly testing the predictions from their simulations with telescope data so they may discover signatures of dark matter behavior in real galaxies.

This next stage could bring scientists closer than ever to understanding what dark matter is, and how it shapes the cosmos.

Materialsprovided byUniversity of Southern California. Original written by Leigh Hopper.Note: Content may be edited for style and length.

An international team of scientists has published a new report that moves towards a better understanding of the behaviour of some of the heaviest particles in the universe under extreme conditions, which are similar to those just after the big bang. The paper, published in the journalPhysics Reports, is signed by physicists Juan M. Torres-Rincón, from the Institute of Cosmos Sciences at the University of Barcelona (ICCUB), Santosh K. Das, from the Indian Institute of Technology Goa (India), and Ralf Rapp, from Texas A&M University (United States).

The authors have published a comprehensive review that explores how particles containing heavy quarks (known as charm and bottom hadrons) interact in a hot, dense environment calledhadronic matter. This environment is created in the last phase of high-energy collisions of atomic nuclei, such as those taking place at the Large Hadron Collider (LHC) and the Relativistic Heavy Ion Collider (RHIC). The new study highlights the importance of including hadronic interactions in simulations to accurately interpret data from experiments at these large scientific infrastructures.

The study broadens the perspective on how matter behaves under extreme conditions and helps to solve some great unknowns about the origin of the universe.

Reproducing the primordial universe

When two atomic nuclei collide at near-light speeds, they generate temperatures more than a 1,000 times higher than those at the centre of the Sun. These collisions briefly produce a state of matter called a quark-gluon plasma (QGP), a soup of fundamental particles that existed microseconds after the big bang. As this plasma cools, it transforms into hadronic matter, a phase composed of particles such as protons and neutrons, as well as other baryons and mesons.

The study focuses on what happens to heavy-flavour hadrons (particles containing charmed or background quarks, such as D and B mesons) during this transition and the hadronic phase expansion that follows it.

Heavy quarks are like tiny sensors. Being so massive, they are produced just after the initial nuclear collision and move more slowly, thus interacting differently with the surrounding matter. Knowing how they scatter and spread is key to learning about the properties of the medium through which they travel.

Researchers have reviewed a wide range of theoretical models and experimental data to understand how heavy hadrons, such as D and B mesons, interact with light particles in the hadronic phase. They have also examined how these interactions affect observable quantities such as particle flux and momentum loss.

"To really understand what we see in the experiments, it is crucial to observe how the heavy particles move and interact also during the later stages of these nuclear collisions," says Juan M. Torres-Rincón, member of the Department of Quantum Physics and Astrophysics and ICCUB.

"This phase, when the system has already cooled down, still plays an important role in how the particles lose energy and flow together. It is also necessary to address the microscopic and transport properties of these heavy systems right at the transition point to the quark-gluon plasma," he continues. "This is the only way to achieve the degree of precision required by current experiments and simulations."

A simple analogy can be used to better understand these results: when we drop a heavy ball into a crowded pool, even after the biggest waves have dissipated, the ball continues to move and collide with people. Similarly, heavy particles created in nuclear collisions continue to interact with other particles around them, even after the hottest and most chaotic phase. These continuous interactions subtly modify the motion of particles, and studying these changes helps scientists to better understand the conditions of the early universe. Ignoring this phase would therefore mean missing an important part of the story.

Understanding how heavy particles behave in hot matter is fundamental to mapping the properties of the early universe and the fundamental forces that rule it. The findings also pave the way for future experiments at lower energies, such as those planned at CERN's Super Proton Super Synchrotron (SPS) and the future FAIR facility in Darmstadt, Germany. ​​​​​​​

Materialsprovided byUniversity of Barcelona.Note: Content may be edited for style and length.

Researchers at Paul Scherrer Institute PSI have demonstrated an innovative method to control magnetism in materials using an energy-efficient electric field. The discovery focuses on materials known as magnetoelectrics, which offer promise for next-generation energy technologies, data storage, energy conversion, and medical devices. The findings are published in the journalNature Communications.

With AI and data centers demanding more and more energy, scientists are searching for smarter, greener technologies. That's where magnetoelectric materials come in — special compounds where electric and magnetic properties are linked. This connection lets researchers control magnetism using electric fields, which could pave the way for super-energy-efficient memory and computing devices.

One such magnetoelectric material is the olive-green crystalcopper oxyselenide(Cu2OSeO₃). At low temperatures, the atomic spins arrange themselves into exotic magnetic textures, forming structures such as helices and cones. These patterns are much larger than the underlying atomic lattice and not fixed to its geometry, making them highly tuneable.

Neutrons watch as electric fields redirect magnetism

Now, scientists at PSI have demonstrated that an electric field can steer these magnetic textures inside copper oxyselenide. In typical materials, magnetic structures – formed from the twisting and alignment of atomic spins — are locked in specific orientations. In copper oxyselenide with the right voltage, the researchers could nudge and reorient them.

This is the first time that the propagation direction of a magnetic texture could be continuously reorientated in a material using an electric field – an effect known as magnetoelectric deflection.

To investigate the magnetic structures, the team used the SANS-I beamline at the Swiss Spallation Neutron Source SINQ, a facility that uses beams of neutrons to map the arrangement and orientation of magnetic structures within a solid at the nanoscale. A custom-designed sample environment enabled the researchers to apply a high electric field whilst simultaneously probing the magnetisation inside the crystal with small-angle neutron scattering (SANS).

"The ability to steer such large magnetic textures with electric fields shows what's possible when creative experiments are paired with world-class research infrastructures," says Jonathan White, beamline scientist at PSI. "The reason we can capture such a subtle effect as magnetoelectric deflection is due to the exceptional resolution and versatility of SANS-I."

The newly discovered magnetoelectric deflection response prompted a deeper investigation into its underlying physics. What they found was intriguing: the magnetic structures didn't just respond — they behaved inthree distinct waysdepending on the strength of the electric field. Low electric fieldsgently deflected the magnetic structures with a linear response.Medium fieldsbrought in more complex, non-linear behaviour. High fieldscaused dramatic 90-degree flips in the direction of propagation of the magnetic texture.

"Each of these regimes present unique signatures that could be integrated into sensing and storage devices," says Sam Moody, postdoctoral researcher at PSI and lead author of the study. "One particularly exciting possibility is hybrid devices that use the ability to tune the onset of these regimes by varying the strength of the applied magnetic field."

The magnetoelectric deflection response offers a powerful new tool to control magnetism without relying on energy-intensive magnetic fields. The high level of flexibility with which the researchers could manipulate the magnetism makes their discovery an exciting prospect for applications in sustainable technology.

Materialsprovided byPaul Scherrer Institute.Note: Content may be edited for style and length.

A giant, strong-jawed salamander once tunneled through ancient Tennessee soil.

And thanks to a fossil unearthed near East Tennessee State University, scientists now better understand how it helped shape Appalachian amphibian diversity.

The giant plethodontid salamander now joins the remarkable roster of fossils from the Gray Fossil Site & Museum.

The findings appeared in the journalHistorical Biology, authored by a team of researchers from the Gray Fossil Site & Museum and ETSU: Assistant Collections Manager Davis Gunnin, Director and Professor of Geosciences Dr. Blaine Schubert, Head Curator and Associate Professor of Geosciences Dr. Joshua Samuels, Museum Specialist Keila Bredehoeft and Assistant Collections Manager Shay Maden.

"Our researchers are not only uncovering ancient life, they are modeling the kind of collaboration and curiosity that define ETSU," said Dr. Joe Bidwell, dean of the College of Arts and Sciences. "This exciting find underscores the vital role our university plays in preserving and exploring Appalachia's deep natural history."

Today, Southern Appalachian forests are renowned for their diversity and abundance of salamander species, especially lungless salamanders of the family Plethodontidae. Tennessee alone is home to more than 50 different salamanders – one in eight of all living salamander species.

Dusky salamanders, common in Appalachian Mountain streams, likely evolved from burrowing ancestors, relatives of Alabama's Red Hills salamander, a large, underground-dwelling species with a worm-like body and small limbs. Their explosive diversification began around 12 million years ago, shaping much of the region's salamander diversity today.

Dynamognathus robertsoni, the powerful, long-extinct salamander recently discovered at the site, had a bite to match its name. Roughly 16 inches long, it ranked among the largest salamanders ever to crawl across the region's ancient forests.

"Finding something that looks like a Red Hills salamander here in East Tennessee was a bit of a surprise," Gunnin said. "Today they're only found in a few counties in southern Alabama, and researchers thought of them as a highly specialized dead-end lineage not particularly relevant to the evolution of the dusky salamanders. Discovery of Dynamognathus robertsoni here in Southern Appalachia shows that these types of relatively large, burrowing salamanders were once more widespread in eastern North America and may have had a profound impact on the evolution of Appalachian salamander communities."

Dynamognathus robertsoni is "the largest plethodontid salamander and one of the largest terrestrial salamanders in the world," Gunnin said. Dusky salamanders in the Appalachians today reach only seven inches long at their largest.

Researchers believe predators like this one may have driven the rapid evolution of Appalachian stream-dwelling salamanders, highlighting the region's key role in salamander diversification.

"The warmer climate in Tennessee 5 million years ago, followed by cooling during the Pleistocene Ice Ages, may have restricted large, burrowing salamanders to lower latitudes, like southern Alabama, where the Red Hills salamander lives today," said Samuels.

Maden explained the naming of this new salamander.

"This group of salamanders has unusual cranial anatomy that gives them a strong bite force, so the genus name – Dynamognathus – Greek for 'powerful jaw,' is given to highlight the great size and power of the salamander compared to its living relatives," said Maden.

The species name robertsoni honors longtime Gray Fossil Site volunteer Wayne Robertson, who discovered the first specimen of the new salamander and has personally sifted through more than 50 tons of fossil-bearing sediment since 2000.

From volunteers and students to staff to faculty, the ETSU Gray Fossil Site & Museum is represented by a dynamic team of lifelong learners and is one of the many reasons ETSU is the flagship institution of Appalachia.

"The latest salamander publication is a testament to this teamwork and search for answers," said Schubert. "When Davis Gunnin, the lead author, began volunteering at the museum as a teenager with an interest in fossil salamanders, I was thrilled, because this region is known for its salamander diversity today, and we know so little about their fossil record. Thus, the possibility of finding something exciting seemed imminent."

Materialsprovided byEast Tennessee State University.Note: Content may be edited for style and length.

Astronomers from the University of Hawaiʻi’s Institute for Astronomy (IfA) have discovered the most energetic cosmic explosions yet discovered, naming the new class of events “extreme nuclear transients” (ENTs). These extraordinary phenomena occur when massive stars—at least three times heavier than our Sun—are torn apart after wandering too close to a supermassive black hole. Their disruption releases vast amounts of energy visible across enormous distances. The team's findings were recently detailed in the journal Science Advances.

"We’ve observed stars getting ripped apart as tidal disruption events for over a decade, but these ENTs are different beasts, reaching brightnesses nearly ten times more than what we typically see," said Jason Hinkle, who led the study as the final piece of his doctoral research at IfA. “Not only are ENTs far brighter than normal tidal disruption events, but they remain luminous for years, far surpassing the energy output of even the brightest known supernova explosions.”

The immense luminosities and energies of these ENTs are truly unprecedented. The most energetic ENT studied, named Gaia18cdj, emitted an astonishing 25 times more energy than the most energetic supernovae known. While typical supernovae emit as much energy in just one year as the Sun does in its 10 billion-year lifetime, ENTs radiate the energy of 100 Suns over a single year.

ENTs were first uncovered when Hinkle began a systematic search of public transient surveys for long-lived flares emanating from the centers of galaxies. He identified two unusual flares in data from the European Space Agency’s Gaia mission that brightened over a timescale much longer than known transients and without characteristics common to known transients.

"Gaia doesn’t tell you what a transient is, just that something changed in brightness," said Hinkle. "But when I saw these smooth, long-lived flares from the centers of distant galaxies, I knew we were looking at something unusual."

The discovery launched a multi-year follow-up campaign to figure out what these sources were. With help from UH’s Asteroid Terrestrial-impact Last Alert System, the W. M. Keck Observatory, and other telescopes across the globe, the team gathered data across the electromagnetic spectrum. Because ENTs evolve slowly over several years, capturing their full story took patience and persistence. Recently, a third event with similar properties was discovered by the Zwicky Transient Facility and reported independently by two teams, adding strong support that ENTs are a distinct new class of extreme astrophysical events.

The authors determined these extraordinary events could not be supernovae because they release far more energy than any known stellar explosion. The sheer energy budget, combined with their smooth and prolonged light curves, firmly pointed to an alternative mechanism: accretion onto a supermassive black hole.

However, ENTs differ significantly from normal black hole accretion which typically shows irregular and unpredictable changes in brightness. The smooth and long-lived flares of ENTs indicated a distinct physical process—the gradual accretion of a disrupted star by a supermassive black hole.

Benjamin Shappee, Associate Professor at IfA and study co-author, emphasized the implications: "ENTs provide a valuable new tool for studying massive black holes in distant galaxies. Because they're so bright, we can see them across vast cosmic distances—and in astronomy, looking far away means looking back in time. By observing these prolonged flares, we gain insights into black hole growth when the universe was half its current age when galaxies were happening places—forming stars and feeding their supermassive black holes 10 times more vigorously than they do today."

The rarity of ENTs, occurring at least 10 million times less frequently than supernovae, makes their detection challenging and dependent on sustained monitoring of the cosmos. Future observatories like the Vera C. Rubin Observatory and NASA’s Roman Space Telescope promise to uncover many more of these spectacular events, revolutionizing our understanding of black hole activity in the distant, early universe.

"These ENTs don’t just mark the dramatic end of a massive star’s life. They illuminate the processes responsible for growing the largest black holes in the universe," concluded Hinkle.

Materialsprovided byUniversity of Hawaii at Manoa.Note: Content may be edited for style and length.

Insect eyes are generally sensitive to ultraviolet, blue and green light. With the exception of some butterflies, they cannot see the color red. Nevertheless, bees and other insects are also attracted to red flowers such as poppies. In this case, however, they are not attracted by the red color, but because they recognize the UV light reflected by the poppy flower.

However, two beetle species from the eastern Mediterranean region can indeed perceive the color red, as an international research team was able to show. The beetles arePygopleurus chrysonotusandPygopleurus syriacusfrom the family Glaphyridae. They feed mainly on pollen and prefer to visit plants with red flowers, such as poppies, anemones and buttercups.

Beetles Have Photoreceptors for long-wave Light

'To our knowledge, we are the first to have experimentally demonstrated that beetles can actually perceive the color red,' says Dr Johannes Spaethe from the Chair of Zoology II at the Biocentre of Julius-Maximilians-Universität (JMU) Würzburg in Bavaria, Germany. He gained the new insights together with Dr Elena Bencúrová from the Würzburg Bioinformatics Chair and researchers from the Universities of Ljubljana (Slovenia) and Groningen (Netherlands). The study has been published in the Journal of Experimental Biology.

The scientists used electrophysiology, behavioral experiments and color trapping. Among other things, they found that the two Mediterranean beetles possess four types of photoreceptors in their retinas that respond to UV light as well as blue, green and deep red light. Field experiments also showed that the animals use true color vision to identify red targets and that they have a clear preference for red colors.

New Model System for Ecological and Evolutionary Questions

The researchers consider the Glaphyrid family to be a promising new model system for investigating the visual ecology of beetles and the evolution of flower signals and flower detection by pollinators.

'The prevailing opinion in science is that flower colors have adapted to the visual systems of pollinators over the course of evolution,' says Johannes Spaethe. However, based on the new findings, it is now possible to speculate whether this evolutionary scenario also applies to Glaphyrid beetles and the flowers they visit.

Why do the researchers think this? The three genera of this beetle family (Eulasia,GlaphyrusandPygopleurus) show considerable differences in their preferences for flower colors, which vary between red, violet, white and yellow. This suggests that the physiological and/or behavioral basis for seeing red and other colors is relatively labile.

The great variety of flower colors in the Mediterranean region and the considerable variation in the color preferences of the beetles made it plausible that the visual systems of these pollinators may adapt to flower colors than is commonly assumed.

Materialsprovided byUniversity of Würzburg.Note: Content may be edited for style and length.