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The northern highlands of Ethiopia are among Africa's oldest agricultural landscapes. Some of the world's most important crops originated here, particularly pulses and grains, including teff. Yet another crop has a less well-known history in Ethiopia's Tigray region: the grapevine.

When an adult refuses to let an injustice pass—stands up to a bully or asserts their rights—we call it principle. When a 15-year-old retaliates to an insult thrown in a school corridor, risking detention, we call it a failure to think ahead. It's easy to ascribe this to a not-yet-developed teenage brain: a convenient shorthand for assuming they simply cannot weigh consequences properly.

In nature, the rarest ingredient can be the one that holds everything together. In a new article published in Trends in Ecology & Evolution, Dr. Erika C. Freeman of the Leibniz Institute of Freshwater Ecology and Inland Fisheries (IGB) in Berlin argues that a handful of scarce molecules can shape entire living communities, far out of proportion to how little is present. These are what ecologists call "keystone molecules."

The laws of thermodynamics state that heat naturally flows from hotter systems or regions to colder systems or regions until a state of thermal equilibrium is reached. This simple principle underpins the operation of numerous technologies, ranging from refrigerators to power plants.

Researchers have developed a DNA vacuum that can suck genetic traces from animals out of the air and reveal which animals live in an area. In two new studies, the researchers collected air samples in three natural areas in Denmark and showed that the method can be used to map local wildlife. This brings them a major step closer to better monitoring biodiversity using DNA from the air.

Northern Eurasia contains about 20% of the world's forests and plays a crucial role in mitigating climate change by absorbing atmospheric carbon dioxide, thereby acting as a major carbon sink. However, understanding the region's carbon sink is challenging because it is influenced by multiple interacting factors, including rapid climate change, wildfires, land-use change and limited observational coverage across its vast extent.

Many molecules exist in two mirror-image forms—like left and right hands—that look identical but can behave very differently, especially in biological systems and pharmaceuticals. Distinguishing between these enantiomers (also called chiral molecules) is a longstanding challenge in science and technology. A useful analogy is that of a screw and a nut: A right-handed screw fits only into a right-handed thread, while a left-handed one will not engage properly.

The fossilized spines of saber-toothed cats in the La Brea Tar Pits reveal evidence of an unexpectedly high prevalence of rare spinal nerve tumors, suggesting that the species became inbred just before extinction. These tumors, which cause significant pain and reduced limb function, could have made the cats particularly vulnerable to the lure of prey animals stuck in the tar pits.

A virtual reality (VR) platform has given researchers new insights into how artificial light at night alters the way coral reef fish respond to predators. The study brings together, for the first time, the metabolic expertise of the University of Glasgow with an innovative immersive virtual reality (VR) platform designed at the Institut de Neurosciences de la Timone and implemented at CRIOBE (Center de Recherches Insulaires et Observatoire de l'Environnement).

Imagine holding one of our most precise quantum devices at a fixed position outside a black hole. A Josephson junction—two superconductors separated by an ultrathin barrier—can turn a voltage into a quantum oscillation with extraordinary precision. Would intense gravity change that quantum rule, or only change how a faraway observer reads the device?

There are countless cultures and societies around the world, spanning thousands of years. One thing they all have in common is that death is a part of everybody's life. Examining how different societies commemorate their dead can give archaeologists and anthropologists insight into how those societies work and what matters to them.

Animals are constantly moving to find food, water, suitable habitats, mates and safe places to rest. Because moving requires substantial energy, animals often rely on various biological and behavioral strategies to reduce unnecessary costs while seeking available resources.

On a boat off the coast of California, Sara Lesser gazes wistfully at dozens of dolphins playing in the vessel's wake. This summer, extreme heat is making such a scene increasingly rare.

A U.S.-Russian space crew landed safely in the steppes of Kazakhstan on Sunday after an eight-month stint on the International Space Station.

A new study has found that mass shootings and deaths by suicide in the United States share seasonal patterns, reaching their highest levels during summer months. Analyzing national data spanning 2014–2021, researchers observed consistent summertime peaks in both mass shootings and suicide deaths, suggesting that common environmental, behavioral or biological factors may contribute to seasonal fluctuations in these forms of violence.

The need for a national deer management strategy to manage the decline of native forests is highlighted in a new research paper published today in the New Zealand Journal of Ecology. Led by Te Whare Wānanga o Waitaha | University of Canterbury (UC) Emeritus Professor David Norton, the paper, "Deer in the headlights: sleepwalking our way to a native forest catastrophe," warns of a slowly developing crisis that is often hard to see.

One of the challenges of searching for technosignatures (i.e., signs that intelligent life somewhere in the universe has created technology) is understanding what to look for. Technology is a very broad area, and different types would show up as different features. One of the most commonly cited is a Dyson sphere, which attempts to encapsulate a star and capture its outgoing light to produce energy. But while we've looked for the mid-infrared waste heat these structures would produce for decades

Black holes represent some of the most extreme environments in the universe. They are the sources of the strongest gravitational fields, allowing us to test Einstein's theory of general relativity to an extent impossible with small objects. But we are also reaching the limit of what we can learn about one remotely. So, various authors have put forward ideas for how we might eventually send a probe directly to a black hole to observe it up close. One of the most vocal of those authors is Cosimo B

The actions of big business shape public health, so local authorities need to carefully consider how to govern their relationships with them.

The way to make a plant grow more may be to take something away. Trimming a section off a plant gene raised rice harvests by up to 25% in new tests by University of Chicago scientists. The plants also showed a better tolerance for drought and heat.

Lithium in drinking water is a widespread and persistent source of human exposure across Tribal communities in the Western United States, according to a new study from Columbia University Mailman School of Public Health. The findings document substantial regional variation in exposure and provide some of the strongest evidence to date that household drinking water is a major contributor to lithium levels measured in the body.

SpaceX's Starship super-rocket deployed operational next-generation Starlink satellites for the first time during its 13th flight test, which addressed snags that arose in the previous test.

Teaching science and religious education (RE) in a more connected way improves students' engagement with science and boosts interest in STEM careers, according to a UCL study. The findings suggest that helping young people see that science and religion can be compatible may encourage greater interest in future STEM (Science, Technology, Engineering and Mathematics) study and careers among students regardless of religious beliefs.

Pennsylvania's roughly 100,000 oil and gas wells produce wastewater that's many times saltier than seawater and contains radium, a known carcinogen. For decades, that saltwater, called brine, was spread on dirt and gravel roads across the state to control dust and on paved roads to melt ice.

When a devastating heat wave, hurricane, flood or wildfire strikes, people often want to know: How much did human-caused climate change influence this event, if at all?

Young people are navigating their romantic and sexual lives in an increasingly complex world. Social media content, including content from misogynistic influencers, has contributed to rapidly changing norms around gender, sex and relationships.

Some people love to swear. In the workplace, some of those people might be in charge.

Five young Pallas's cats—dubbed the world's grumpiest felines for their sullen facial expressions—went on display at a zoo in Japan on Thursday.

As the construction of a hydroelectric dam loomed, archaeologists raced to uncover Angola's earliest dated burials and its only known cremation at a 15th-century settlement before it vanished beneath the water.

In the increasingly polarized political realm, moderates may be viewed as disloyal by both conservatives and liberals when the opposing side seems threatening, according to research published in the Journal of Experimental Psychology.

By analyzing the data from NASA's Fermi gamma-ray space telescope, Chinese astronomers have investigated a recently identified millisecond pulsar known as PSR J0435+3233. As a result, they found that the pulsar exhibits gamma-ray pulsations. The discovery was detailed in a paper published July 17 on the pre-print server arXiv.

When you pick up a gallon (3.8 liters) of milk at the store, the nutrients it contains may depend on both what's on the label and the time of year. A new study reports that omega-3 fatty acids are highest in milk labeled as organic grass-fed and lowest in conventionally produced milk. Other fatty acids varied by dairy production method and season.

Firefighters battled massive blazes tearing through forests across France and Spain on Monday, as authorities warned of a fresh heat wave set to engulf the scorched French wine-growing region around the major city of Bordeaux.

The gigantic wildfire ravaging southwestern France has created an extremely dangerous "pyrocumulonimbus"—a phenomenon never before seen in the country—the spokesman for the country's National Firefighters Federation of France (FNSPF) told AFP.

Searching for extraterrestrial intelligence has so far primarily meant focusing on one particular type of signal—and that signal has normally been based on our own current cutting-edge technology. But what if that's the wrong way to look for signs of alien intelligence? What if a resource-conscious civilization decided it was too complicated to send femtosecond lasers in high-energy bursts across the universe? A new paper, available as a preprint on arXiv, from researchers Dániel Apai, Chia-Lung

Insect wings are bristling with senses, feeling the wind blowing and even tasting potential mates, but little was known about whether moth wings are equipped with a sense of smell. Sonja Bisch-Knaden and Bill Hansson from the Max Planck Institute for Chemical Ecology, Germany, had a hunch that moth wings might be able to sniff out certain aromas.

The idea of having living fungi cover your body might not be the most appealing thing in the world. But what if it was part of a clothing fabric that could change color, protect you from UV rays and even repair its own tears? Those are just some of the possibilities of a new material described in a paper published in the journal Science.

Researchers have uncovered a surprising mechanism that allows plants to carefully coordinate the formation and growth of new leaf parts. The study shows that the hormone auxin regulates different phases in organ formation by oppositely affecting the activity of another hormone, gibberellin, to trigger the formation of new leaf structures before reversing course and boosting gibberellin to drive their expansion. The findings offer new insight into how plants build complex organs and could eventua

Biomedical engineers at Duke University have demonstrated a method for systematically developing novel, complex combinations of probiotics and prebiotics to more effectively maintain gut health and treat various gastrointestinal diseases.

The descriptions of the two new additions to the European snail fauna, named Cochlostoma komarnica and Cochlostoma dobrido, have been published in the open-access Biodiversity Data Journal.

"Shark Week," which kicks off this week, has captivated audiences for decades with stories of these powerful ocean predators. But the secret behind their extraordinary swimming abilities lies far deeper than their impressive teeth or iconic tails—it's hidden inside their spines.

A new study published in Nature Physics reports the first direct experimental evidence of a Floquet topological state, a novel light-induced phase of matter that, until now, has existed only on paper and in simulations. Topological insulators can conduct electricity along their surface while remaining insulating throughout their bulk. Physicists have spent years developing Floquet engineering, a technique that uses intense, rapidly oscillating light fields to temporarily reshape a material's ele

What dangers does smoke from wildfires pose? Who is most at risk? Here are some answers to health questions often asked, especially now with fires in France and Spain.

Neural networks have transformed how machines find patterns in data, from recognizing faces in photos to predicting the shapes of proteins. So far, all of this progress has been made on ordinary classical computers, but with quantum computers now edging into practical use, there is a real possibility that neural networks could tap into distinctly quantum effects and operate in ways that classical machines never could. So far, however, neural networks have proven far more difficult to run on quan

Scottish firefighters fought a wildfire Saturday that was burning through Cairngorms National Park in the north, with authorities advising residents to evacuate.

Thousands crowded into emergency shelters in France and Spain on Sunday after wildfires drove more than 300,000 people to flee their homes and vacation accommodations.

In the words of a former Antarctic tour guide we interviewed: "You'd see massive glacier calvings, and you'd just want to cry. But all the guests would be cheering. And you'd be like … 'can you not put two and two together?'"

A Taiwan–led study of Mandarin-speaking learners shows that the sounds we hear and produce are deeply shaped by our prior language experience, offering new insights into how humans learn and use language.

When Amy posts a photograph of herself on Instagram, she knows what will attract attention. A picture of her in a bikini may receive thousands of views. A post explaining the realities of living with a stoma (an opening in her abdomen that directs waste to a bag attached to it) may reach far fewer people.

Swidden agriculture—often called "slash-and-burn"—has been practiced on every inhabited continent throughout human history, and for decades it has been blamed for the destruction of the world's rainforests. However, a new study of more than 18,000 forest patches around the world found that the environmental impact of swidden is more nuanced and less destructive than the term "slash-and-burn" suggests—and that unwritten social rules in small societies, not government oversight, often regulate lan