Category: 7. Science

About 56 million years ago, when Earth experienced a dramatic rise in global temperatures, one meat-eating mammal responded in a surprising way: It started eating more bones.

That’s the conclusion reached by a Rutgers-led team of researchers, whose recent study of fossil teeth from the extinct predator Dissacus praenuntius reveals how animals adapted to a period of extreme climate change known as the Paleocene–Eocene Thermal Maximum (PETM). The findings, published in the journal Palaeogeography, Palaeoclimatology, Palaeoecology, could help scientists predict how today’s wildlife might respond to modern global warming.

“What happened during the PETM very much mirrors what’s happening today and what will happen in the future,” said Andrew Schwartz, a doctoral student in the Department of Anthropology at the School of Arts and Sciences, who led the research. “We’re seeing the same patterns. Carbon dioxide levels are rising, temperatures are higher and ecosystems are being disrupted.”

Associate Professor Robert Scott of the Department of Anthropology is a co-author of the study.

Schwartz, Scott and another colleague used a technique called dental microwear texture analysis to study the tiny pits and scratches left on fossilized teeth. These marks reveal what kinds of food the animal was chewing in the weeks before it died.

The ancient omnivore was about the size of a jackal or a coyote and likely consumed a mix of meat and other food sources like fruits and insects. “They looked superficially like wolves with oversized heads,” Schwartz said, describing them as “super weird mammals.” “Their teeth were kind of like hyenas. But they had little tiny hooves on each of their toes.”

Before this period of rising temperatures, Dissacus had a diet similar to modern cheetahs, eating mostly tough flesh. But during and after this ancient period, its teeth showed signs of crunching harder materials, such as bones.

“We found that their dental microwear looked more like that of lions and hyenas,” Schwartz said. “That suggests they were eating more brittle food, which were probably bones, because their usual prey was smaller or less available.”

This dietary shift happened alongside a modest reduction in body size, likely because of food scarcity. While earlier hypotheses blamed shrinking animals on hotter temperatures alone, this latest research suggests that limited food played a bigger role, Schwartz said.

This period of rapid global warming lasted about 200,000 years, but the changes it triggered were fast and dramatic. Schwartz said studies of the past like his can offer practical lessons for today and what comes next.

“One of the best ways to know what’s going to happen in the future is to look back at the past,” he said. “How did animals change? How did ecosystems respond?”

The findings also highlight the importance of dietary flexibility, he said. Animals that can eat a variety of foods are more likely to survive environmental stress.

“In the short term, it’s great to be the best at what you do,” Schwartz said. “But in the long term, it’s risky. Generalists, meaning animals that are good at a lot of things, are more likely to survive when the environment changes.”

Such an insight may be helpful for modern conservation biologists, allowing them to identify which species today may be most vulnerable, he said. Animals with narrow diets, such as pandas, may struggle as their habitats shrink. But adaptable species, including jackals or raccoons, might fare better.

“We already see this happening,” Schwartz said. “In my earlier research, jackals in Africa started eating more bones and insects over time, probably because of habitat loss and climate stress.”

The study also showed that rapid climate warming as seen during the ancient past can lead to major changes in ecosystems, including shifts in available prey and changes in predator behavior. This may suggest that modern climate change could similarly disrupt food webs and force animals to adapt, or risk extinction, he said.

Even though Dissacus was a successful and adaptable animal that lived for about 15 million years, it eventually went extinct. Scientists think this happened because of changes in the environment and competition from other animals, Schwartz said.

Schwartz conducted his research using a combination of fieldwork and lab analysis, focusing on fossil specimens from the Bighorn Basin in Wyoming, a site with a rich and continuous fossil record spanning millions of years. Schwartz chose the location because it preserves a detailed sequence of environmental and ecological changes during the ancient period of climate warming.

Schwartz has been interested in paleontology, specifically dinosaurs, since he was a boy, journeying with his father, an amateur fossil hunter, on treks through New Jersey’s rivers and streams. Now, as a late-stage doctoral student, he hopes to use ancient fossils to answer urgent questions about the future.

He also wants to inspire the next generation of researchers.

“I love sharing this work,” he said. “If I see a kid in a museum looking at a dinosaur, I say, ‘Hey, I’m a paleontologist. You can do this, too.’”

In addition to Schwartz and Scott, Larisa DeSantis of Vanderbilt University is an author of the study.

Explore more of the ways Rutgers research is shaping the future

On July 4, 2025, a NASA-backed telescope in Maui, Hawaii, Pan-STARRS2, spotted a wild little asteroid zipping through space. Nicknamed 2025 OW, this rocky rebel is about 200 feet wide, shaped like a cosmic potato, and spins like a top on espresso, one full rotation every 90 to 180 seconds!

Thanks to radar from Goldstone, scientists got a close-up look, spotting surface details as small as 12 feet across. That makes 2025 OW one of the fastest-spinning near-Earth asteroids ever caught on radar.

On July 28, 2025, NASA’s Goldstone radar snapped a series of 41 images of asteroid 2025 OW as it cruised past Earth. No need for panic, this space rock kept a respectful distance of 400,000 miles, about 1.6 times farther than the Moon.

It was a cosmic flyby, not a collision course. Just another day of Earth dodging space debris like a pro.

Asteroids aren’t just drifting rocks; they’re dancers in space, and sunlight is their choreographer. When sunlight hits an asteroid’s bumpy surface, it’s absorbed and re-emitted unevenly. Each escaping photon carries a whisper of momentum, gently nudging the asteroid into a spin. This slow but steady torque is called the YORP effect, like sunlight giving the asteroid a cosmic twirl.

For asteroid 2025 OW, spinning once every couple of minutes, that’s a dizzying pace! To keep from flying apart, it likely isn’t a loose pile of space gravel. Instead, it may be a solid chunk of rock, tough enough to hold itself together while spinning like a record in zero gravity.

Thanks to radar snapshots from NASA’s Goldstone Observatory, scientists now have a much clearer idea of asteroid 2025 OW’s path, not just today, but for decades to come. The data helped tighten predictions about its distance from Earth and future movements.

It’s July 28, 2025, and flyby was the closest it’ll get to Earth anytime soon. So while it gave us a good look this time, 2025 OW is heading back to the cosmic highway. For now, Earth can breathe easy.

The Great Barrier Reef has suffered its biggest annual drop in live coral in two out of three areas monitored by scientists since 1986, a new report has revealed.

The Australian Institute of Marine Science (Aims) report is the first to comprehensively document the devastating impacts of the early 2024 mass coral bleaching event – the most widespread and severe on record for the Great Barrier Reef.

In the months that followed that event, scientists described a “graveyard of corals” around Lizard Island in the north and a study recorded the death of 40% of corals at One Tree Island in the south.

Aims has conducted annual in-water surveys of the world’s biggest reef system since 1986, checking the health and extent of corals.

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This year’s survey report found that in the reef’s northern section – between Cooktown and the tip of Cape York – bleaching, two cyclones and associated flooding had caused coral cover to fall by 25%.

In the southern section, from Mackay to just north of Bundaberg, coral cover had fallen by 30%. The northern and southern zones suffered the highest annual drops on record.

Coral cover fell by 13% in the central section, which had escaped the worst of the heat in 2024.

Dr Mike Emslie, who leads the long-term reef monitoring program at Aims, said coral cover was becoming more volatile.

“It has been a pretty sobering year of surveys with the biggest impacts I have seen in the 30-plus years I have been doing this,” he said.

“This volatility is very likely a sign of an unstable system. That’s our real concern. We’re starting to see record highs in coral cover that quickly get turned around to record falls.”

Quick Guide

What is coral bleaching?

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Coral bleaching describes a process whereby the coral animal expels the algae that live in its tissues and give it its colour and much of its nutrients.

Without its algae, a coral’s white skeleton can be seen through its translucent flesh, giving off a bleached appearance.

Mass coral bleaching over large areas, first noticed in the 1980s around the Caribbean, is caused by rising ocean temperatures.

Some corals also display fluorescent colours under stress when they release a pigment that filters light. Sunlight also plays a role in triggering bleaching.

Corals can survive bleaching if temperatures are not too extreme or prolonged. But extreme marine heatwaves can kill corals outright.

Coral bleaching can also have sub-lethal effects, including increased susceptibility to disease and reduced rates of growth and reproduction.

Scientists say the gaps between bleaching events are becoming too short to allow reefs to recover.

Coral reefs are considered one of the planet’s ecosystems most at risk from global heating. Reefs support fisheries that feed hundreds of millions of people, as well as supporting major tourism industries.

The world’s biggest coral reef system – Australia’s Great Barrier Reef – has suffered seven mass bleaching events since 1998, of which five were in the past decade. 

With relatively benign impacts from cyclones and bleaching in the five years before the 2024 event, coral cover had reached record levels in some places.

But that recovery, Emslie said, was largely driven by fast-growing acropora corals that were more susceptible to heat stress.

“We had said it could all get turned around in one year and, low and behold, here we are,” he said, adding that coral cover was now mostly back in line with long-term averages.

‘Closer and closer’

The 2024 and 2025 events were part of an ongoing global mass coral bleaching event that led to more than 80% of the planet’s reefs being hit with enough heat to cause bleaching, affecting corals in at least 82 countries and territories.

A study last year found ocean temperatures on the Great Barrier Reef were likely at their hottest for at least 400 years and were an “existential threat” to the Unesco World Heritage-listed reef.

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Widespread mass bleaching of the Great Barrier Reef was first seen in 1998 and happened again in 2002, 2016, 2017, 2020, 2022, 2024 and 2025.

Emslie said: “These impacts we are seeing are serious and substantial and the bleaching events are coming closer and closer together.

“We will ultimately get to a tipping point where coral cover can’t bounce back because disturbances come so quickly that there’s no time left for recovery.

“We have to mitigate the root causes of the problem and reduce emissions and stabilise temperatures.”

The Aims report comes a month before the federal government is due to reveal its emissions reduction target for 2035.

The Albanese government promised Unesco last year it would “set successively more ambitious emissions reduction targets” that would be “in alignment with efforts to limit global temperature increase to 1.5C”.

Last week, the Climate Change Authority, which will advise the government on what target to set, released a report that said holding warming “as close as possible to 1.5C” was key to addressing the threats facing the reef.

Richard Leck, head of oceans at WWF Australia, said the government needed to set a target consistent with 1.5C.

“This is the one action the government can take to give the reef a fighting chance.”

This is the first time silicate emission has been detected in planetary-mass objects.

Giant free-floating planets could make their own miniature planetary systems without needing a star to orbit around, finds a new study from Scotland’s University of St Andrews.

Scientists investigated eight young and isolated cosmic objects with masses five to 10 times that of Jupiter using the James Webb Space Telescope (JWST). For comparison’s sake, Jupiter is around 318 times as massive as Earth.

These objects are comparable to giant planets in their properties, but they don’t orbit around a star. Instead, they float freely in space.

Current research suggests that these are the lowest mass objects formed from the collapse of giant gas clouds, similar to stars. However, unlike stars, these planets do not accumulate enough mass to start any fusion reactions at their cores.

Scientists suggest that these free-floating planets could have formed in a similar manner to other planets, in orbit around a star, but later ejected from orbit to float on their own.

These objects are difficult to observe since they are very dim – as they do not emit light – and radiate mostly in the infrared spectrum.

So, in order to study them, the team, made up of researchers from the School of Physics and Astronomy at St Andrews, along with co-authors from Ireland, England, the US, Italy and Portugal, used instruments on the JWST that are extremely sensitive to infrared light. The team analysed detailed spectroscopic observations for these objects from August to October 2024.

Their findings characterises these objects in depth and confirm that they have masses around the same size as Jupiter. Six of them also have excess emission in the infrared spectrum caused by warm dust in their immediate surrounding.

According to the study published last week, these emissions are a sign of disks around the objects, which are generally the birthplaces of planets.

In addition, observations also show emission from silicate grains in these disks, with clear signs of dust growth and crystallisation, which is typically the first steps in the formation of rocky planets.

Although silicate emission has been found in stars and brown dwarfs before, this is its first detection in planetary-mass objects.

The latest finding builds on another study published from the University of St Andrews, which showed that disks around free-floating planetary mass objects can last several million years, giving them enough time to form planets.

“Taken together, these studies show that objects with masses comparable to those of giant planets have the potential to form their own miniature planetary systems. Those systems could be like the solar system, just scaled down,” said Dr Aleks Scholz, the principal investigator of the project.

“Whether or not such systems actually exist remains to be shown.”

In another recent study, scientists, for the first time, observed the very early stages of the creation of a new solar system around a baby star.

The newborn planetary system that was just discovered is emerging around HOPS-315, a baby star around 1,300 light-years away. Astronomers say that Hops-315 is comparable to the sun.

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The authors analyzed over one million papers and preprints published between 2020 and 2024, focusing on abstracts and introductions. These are the sections most often edited with the help of language models. To detect signs of AI use, the researchers applied statistical methods that track the frequency of certain words commonly found in AI-generated text, such as “pivotal,” “showcase,” and “intricate.”

According to James Zou, a co-author of the study and a computational biologist at Stanford University, a sharp increase in AI-generated content was seen just months after ChatGPT became publicly available. The trend was especially strong in fields closely tied to artificial intelligence, including computer science, electrical engineering, and related areas.

By comparison, signs of language model use were found in only 7.7% of math abstracts, with even lower rates in biomedical research and physics. Still, the trend is gradually spreading across all scientific fields.

Early on, the academic community tried to limit the use of generative AI. Many journals introduced policies requiring authors to disclose if such tools were used.

In practice, though, enforcing these rules has proven difficult. Some papers included obvious traces of language models, such as phrases like “regenerate response” or “my knowledge cutoff.” Researchers, including University of Toulouse computer scientist Guillaume Cabanac, began compiling databases of questionable publications.

Today, detecting AI involvement is becoming increasingly difficult. Authors have learned to avoid giveaway phrases, and current detection tools often deliver inconsistent results, especially when evaluating work by non-native English speakers.

Risks and challenges

Although the study focused mainly on abstracts and introductions, co-author and data scientist at the University of Tübingen, Dmitry Kobak warns that researchers may increasingly turn to AI to write sections that review previous studies. This could make those parts of papers more uniform and eventually create a vicious cycle, where new language models are trained on content generated by earlier ones.

The publication of AI-generated papers that include errors or fabricated information raises concerns about the reliability of the peer review process and may undermine trust in scientific publishing overall.

Earlier, Kazinform News Agency reported on the influence of artificial intelligence on the labor market and future jobs.

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

This is a summary of: Wang, G. et al. Spatial quantitative metabolomics enables identification of remote and sustained ipsilateral cortical metabolic reprogramming after stroke. Nat. Metab. https://doi.org/10.1038/s42255-025-01340-8 (2025).

Newswise — Rather than completely burning up when a spacecraft reenters Earth’s atmosphere, its heat shield’s outer surface is sacrificed to protect the rest of the vehicle. The carbon fibers decompose, dissipating the heat. It was assumed that this only happens on the surface, but in a recent study, researchers from The Grainger College of Engineering, University of Illinois Urbana-Champaign and four other institutions gained new information about how the protective carbon fiber material evolves, not just at the surface, but beneath, where structural failure could occur and threaten the life of the vehicle.  

“We often assume that degradation of the heat shield only happens at the surface, which is not always a bad assumption. But given the degradation we observed throughout the material volume, our work shows that this assumption does not always hold, demonstrating that the heat shield’s structural integrity can be significantly compromised under certain conditions,” said aerospace engineering Ph.D. student Ben Ringel. “Also, this in-depth weakening could lead to spallation—when large chunks of material are torn off, causing the thermal protection system to degrade faster.”

According to Ringel’s advisor, Francesco Panerai, “The oxidation of carbon fiber is a key process in thermal protection. It is also one of the most studied in material science and its theory is very well established. But here, we executed an elegant, simple, although very difficult to execute, experiment. For the first time, we could see this theory in action, with some unexpected twists.”

Panerai and his collaborators at the Berkeley Lab Advanced Light Source performed the experiments at the Paul Scherer Institute in Switzerland. They used the TOMCAT beamline at the Swiss Light Source—a specialized facility where dynamic processes can be tracked in space and time, using an ultra-fast end station and a special camera system that resolves micron-scale structures with sub-second time resolution for extended durations.

The team subjected small samples of ablative carbon fiber material to heat under the bright X-rays of TOMCAT, collecting a time-series of 3D images of the sample as it rotated and was consumed by oxygen.

“The level of detail that TOMCAT provided was incredible,” Panerai said. “We could observe fiber ablation at a resolution that we had not seen before.”

Ringel was given about 19 TB of raw data collected in Switzerland and began processing it.

“After reconstructing the data, I used deep learning to segment it—identifying the fibers from the void,” Ringel said. “It was a huge data management challenge. From the beginning, I could qualitatively see a shift in material response between conditions.”

Next came intensive analysis. He examined how easily oxygen diffuses through the material compared to how quickly it reacts with the carbon fibers.

“There’s a finite amount of oxygen that’s available to react with the carbon fibers. In high-temperature cases, reactions happen fast, and the oxygen doesn’t have time to diffuse into the material before getting eaten up at the surface,” Ringel said. “But, as the temperature decreases, reactions slow down, giving the oxygen time to percolate through the material, leading to weakening of fibers throughout the volume of the material.

“We captured this happening. We visualized and quantified how deep into the material reactions were occurring based on temperature and pressure. We mapped them using non-dimensional analysis, which describes the competition between diffusion and reaction rates in materials. Our numbers from the images correlated with what we saw.”

The second phase of the analysis involved a close collaboration with NASA’s Ames Research Center. Ringel and colleagues used NASA’s Porous Microstructure Analysis software on the National Energy Research Scientific Center supercomputer to run over 1,600 material property simulations.

“Simulations utilized our evolving 3D images, providing us with information on properties of the material at each timepoint. We also developed a novel method to calculate the properties of the material as a function of both time and space. For the first time, we can see how the properties change throughout the heat shield material under varying diffusion-reaction regimes.”

The information generated from this research on diffusion and reaction is invaluable for advancing modern ablation models, enhancing heat shield performance, and tailoring materials to specific operational conditions.

“Our data provides valuable measurements to help other heat shield researchers validate and improve their ablation models, which are then applied to in-flight vehicles.

“With an improved understanding of how diffusion-reaction competition influences heat shield degradation throughout flight, a world of innovative engineering becomes possible. This knowledge empowers the development of advanced manufacturing approaches, such as 3D-printed heat shields with precisely engineered internal structures designed to meet the specific conditions of hypersonic reentry.”

The study, “Carbon Fiber Oxidation in 4D,” written by Benjamin M. Ringel and Francesco Panerai from Illinois; Federico Semeraro, and Bruno Dias from AMA Inc at NASA’s AMES; Joseph C. Ferguson from Stanford University; Harold S. Barnard, Sam Schickler, Kara Levy, Shawn Shacterman, Talia Benioff-White, Julian Davis, Alastair A. MacDowell and Dilworth Y. Parkinson from Advanced Light Source at Lawrence Berkeley National Laboratory; C.M. Schlepütz from Swiss Light Source at the Paul Scherrer Institute; and Edward S. Barnard from the Molecular Foundry at Lawrence Berkeley National Laboratory. It is published in and featured on the cover of Advanced Materials. DOI:10.1002/adma.202502007

This work was supported by grants from the Air Force Office of Scientific Research and NASA. Advanced Light Source is a facility funded by the Department of Energy.

Get ready stargazers: the Perseid meteor shower peaks next week, Aug. 12-13, bringing up to 100 shooting stars per hour, along with the potential for dazzling fireballs

The Perseid meteor shower occurs each year as Earth barrels through the trail of ancient debris shed by comet 109P/Swift-Tuttle. These cometary fragments — often no larger than a grain of sand — collide with Earth’s atmosphere at speeds of up to 37 miles (59 kilometers) per second. The resulting friction swiftly vaporizes the debris, creating the bright flashes that we see as fiery “shooting stars”.