The causes of inflammatory bowel disease (IBD) are poorly understood, but now, scientists have pinpointed a runaway immune response that may underlie the condition in some patients.

IBD, which is characterized by chronic inflammation in all or part of the digestive tract, affects millions of people worldwide. Its principal forms are Crohn's disease, which can occur at any point of the gastrointestinal tract, and ulcerative colitis, which affects only the colon and rectum.

While IBD patients may experience similar inflammation, the underlying cause may be different. Understanding those differences could potentially unlock new, targeted angles for treatment, researchers concluded in the new study.

"Identifying these patients early could eventually allow clinicians to move more quickly toward therapies that address the specific mechanism of disease rather than relying on a trial-and-error sequence of medications," Dr. Brad Pasternak, medical director of the IBD Clinic at Phoenix Children's Hospital, who was not involved in the work, told Live Science in an email.

A potential subtype of IBD

The genetics of IBD are complex, with past studies linking the condition to 300 "hotspots" throughout the genome. The strongest known genetic risk factor for ulcerative colitis is a gene variant called HLA-DRB1*01:03, but how this variant contributes to IBD has been unclear.

The new study, published June 10 in The New England Journal of Medicine, helps connect the dots.

A major clue had emerged in previous research by the same team, which tested the blood of two children with IBD. The kids had autoantibodies — immune proteins that target the body itself rather than germs — that were neutralizing a key anti-inflammatory protein called interleukin-10 (IL-10).

IL-10 normally works by inhibiting the secretion of pro-inflammatory proteins, so patients whose bodies block IL-10 are effectively releasing a brake that should be holding off inflammation, Pasternak said.

The researchers suspected that these autoantibodies could be one factor causing IBD. In their latest study, they sought to find out whether more IBD patients had the same autoantibodies.

The study included data from over 4,900 people with IBD and over 1,000 without the condition. Using two separate lab tests, the researchers analyzed blood samples from both groups, finding the autoantibody in 173 of the IBD patients, or about 3.5%. The autoantibody was virtually absent from the blood of the comparison group.

Then, in lab experiments, the team exposed immune cells to blood from the IBD patients who carried the autoantibody. This lowered the amount of IL-10 while triggering a pro-inflammatory response.

Study co-author Dr. Holm Uhlig, a pediatric gastroenterologist at the University of Oxford, told Live Science that identifying what drives the formation of the autoantibodies will be "a question of intense interest." For now, though, their data suggests that patients carrying HLA-DRB1*01:03 are far more likely to have autoantibodies blocking IL-10 than those without the variant.

Historically, the variant has been associated with severe IBD that can require major surgery to treat. "Currently, autoimmune responses are not at all part of the therapeutic repertoire, and that's why we feel it's a relevant study," Uhlig said.

Uhlig also noted that the subgroup of 3.5% of patients they identified is a "significant number," given the large overall number of IBD patients worldwide.

In general, many IBD patients are currently treated with therapies that broadly suppress inflammatory pathways, Pasternak said, but not everyone responds to treatment. This study points to a potential way to someday tailor treatments to the mechanism driving specific patients' diseases, he said.

Aside from offering personalized treatments for IBD patients, Uhlig said their findings may improve diagnoses.

"Patients could undergo genetic testing already in the early stage of their disease diagnosis," he said, "and then it would determine their susceptibility to develop autoantibodies."

This article is for informational purposes only and is not meant to offer medical advice.

Researchers have identified a new species of "walking shark," a rare group of small carpet sharks that use their fins to "walk" along shallow reefs.

A team of divers spotted the newfound shark, which they named Hemiscyllium dudgeonae, in the dark waters around the reefs of southeastern Papua New Guinea. Gliding along the rocks was a small, brown-spotted shark that they didn't recognize.

"I was so excited. … I didn't look very closely at the pattern and quickly caught it and took it back to the boat," Christine Dudgeon, a senior research fellow at the University of the Sunshine Coast in Australia, told Live Science in an email.

Dudgeon handed the shark to Jess Blakeway, a doctoral student and first author of a new study describing the shark. Blakeway "noticed that the shark had a different pattern to the one that we were looking for and called out to me: 'Chris, it's different.'"

The new shark is named the Dudgeon's walking shark after Dudgeon, in recognition of her 20 years of researching the Hemiscyllium genus.

The new find, described June 15 in the Journal of the Ocean Science Foundation, brings the number of known walking shark species to 10, each with their own unique body pattern.

"This discovery is exciting because a lot of new fishes, and in particular, new shark and ray species, tend to be deep sea, so finding something in very shallow [less than 3 feet, or 1 meter] of water is unusual and highlights that there is potentially a lot of biodiversity that we really don't know about," Dudgeon said.

Encountering a new species

The team had been searching for another walking shark species, called Michael's walking shark (Hemiscyllium michaeli), when they encountered the unusual shark.

"Michael's walking shark has leopard prints and Dudgeon's walking shark has small white dashes and brown dots all over its body," Dudgeon said. "But with only one specimen we were not sure if this was an anomaly or a true difference."

The researchers continued surveying nearby reefs, and within two days, they had located 11 additional Dudgeon's walking sharks across three sites. These included males and females, both juveniles and adults, with all displaying the distinctive body pattern. That consistency convinced the team that they were likely looking at an undescribed species.

Dudgeon and Blakeway used genetic data to test this hypothesis at their laboratory in Australia. By comparing DNA from the newly discovered sharks with genetic samples from the other nine walking shark species, they confirmed that the population represented a new species.

Walking on land

Walking sharks are notable for their unusual biology. Unlike larger, open-ocean shark species, walking sharks spend their lives near coral reefs. Their ability to "walk" across the seafloor using their pectoral and pelvic fins is particularly useful during low tide, when parts of the reef become isolated from deeper waters. "Walking" helps the animals remain active when oxygen levels drop so that they can continue hunting prey across reef flats.

Scientists think this ability evolved as a response to the challenging environment of tropical reef flats, where oxygen levels can shift dramatically as the tides rise and fall.

Studies indicate that some walking sharks can survive in low oxygen environments for hours, though more research is needed to understand how the sharks are able to do this, Dudgeon said.

So far, Dudgeon's walking shark has been documented at only three locations in Papua New Guinea. If future research confirms that the species has a highly restricted range, H. dudgeonae could be vulnerable to habitat degradation, climate change or overfishing.

Many walking shark species appear to stay close to the reefs where they were born, which limits their ability to recolonize damaged habitats. Species with small geographic ranges are often more susceptible to population declines because local disturbances can affect a larger portion of the total local population.

The discovery also shows how new shark species are still being found in regions that have received relatively little scientific attention. Dudgeon and her team plan to continue doing surveys in Papua New Guinea to study the new species in its home environment.

"I think many people are not aware of the wonderful diversity of sharks and their relatives, the rays, skates and chimeras," Dudgeon said. "Very few species are dangerous to humans and they are a wonderfully broad and eclectic group of animals. They continue to surprise and fascinate us."

How much of a shark fan are you? Find out with our shark quiz!

The patient: A 29-year-old woman in Lithuania

The symptoms: The woman had been trying to conceive with her male partner but had not become pregnant. Two rounds of in vitro fertilization (IVF) also failed to produce a pregnancy, but gynecological exams did not find any underlying causes for why she was unable to become pregnant. (When the patient's doctors described the case in a report, they did not mention if any fertility tests were also conducted on her partner.)

However, the woman had a history of asthma and sensitivity to inhaled allergens, such as mold, cat fur and dust. So she visited a medical facility to see if her allergies might be affecting her fertility.

What happened next: At the facility, blood tests revealed that the woman had unusually high amounts of eosinophils, a type of white blood cell that defends the body against allergens. Skin tests showed that, in addition to the woman's known allergy triggers, she was sensitive to mites, pollen from weeds and grasses, and allergens from insects and dogs.

The patient was especially sensitive to a protein called Canis familiaris allergen 5 (Can f 5), which is found in dog dander and urine. Sensitivity to Can f 5 can also indicate sensitivity to similar types of proteins found in human semen, the doctors wrote in the report.

In an interview with an allergist at the facility, the patient confirmed that she experienced nasal congestion and sneezing after unprotected intercourse with her male partner. These symptoms were previously overlooked by other specialists during consultations about her inability to conceive, she reported.

The diagnosis: Doctors then conducted further allergy tests using samples of semen collected from the woman's partner. The patient's allergic response confirmed the doctors' suspicions that she had a human seminal plasma allergy. (Seminal plasma is the fluid component of semen that carries the sperm cells.)

Sensitivity to semen "is a potential cause of female infertility," because such allergies can trigger inflammation in reproductive organs, according to the report. It's not immediately clear if the allergy somehow complicated the woman's IVF treatments, as well, given semen would not have been present in the implanted embryos.

The treatment: Barrier contraception — namely, condom use — is the most common intervention for a semen allergy. However, the patient was still eager to conceive with her partner, so she rejected that strategy.

The only known treatment for reducing sensitivity to semen involves introducing the fluid into the patient's body in gradually increasing concentrations, to build up their tolerance to the allergens. But this course of treatment was unavailable in Lithuania, the doctors wrote. Instead, they recommended that the woman take antihistamine medication before intercourse to reduce the severity of her allergic reactions.

She followed their instructions but found this approach "ineffective," the doctors wrote. During a follow-up visit three years later, the woman said that she had still been unable to conceive. What's more, new allergic symptoms now appeared after contact with her partner's semen, including a burning sensation in her vulva, puffy eyelids and watery eyes. No further treatments were recommended, according to the report.

What makes the case unique: Worldwide, medical experts have documented about 80 cases of human seminal plasma allergy, and there is still much to be learned about its impact on pregnancy, especially in the presence of other health-related issues that could hinder conception.

The causes of infertility are often difficult to pinpoint. Therefore, "this case serves as a reminder that seemingly unrelated allergic conditions, when combined, can contribute to reproductive health challenges, warranting comprehensive evaluations," the woman's doctors wrote.

This article was first published July 23, 2025.

This article is for informational purposes only and is not meant to offer medical advice.

When galaxies collide, it's less like a train wreck and more like a marriage: Two separate entities merge into a single massive celestial structure. But relationships are hard, whether you're a human or a galaxy — and ,this process may also "kill" the merging galaxies by unleashing star-quenching winds.

This mechanism may help to explain an enigma in the early universe. A glut of James Webb Space Telescope (JWST) observations have shown that galaxies grew surprisingly massive within 1 billion years of the Big Bang. Just as unexpectedly, many of these galaxies appear to have already stopped producing stars and grown quiescent (or dead) only about a billion years later.

Galactic winds have previously been considered as galaxy-killing culprits, but astronomers lacked the direct evidence to confirm that this process can meaningfully suppress star formation at such an early stage of cosmic history. Now, in a paper published June 10 in the journal Monthly Notices of the Royal Astronomical Society, an international team of astronomers has described how star-driven winds can quench galaxies, creating the kaleidoscope of quiescent structures observed by JWST.

Gas leak near the dawn of time

The researchers used JWST and the Atacama Large Millimeter/submillimeter Array radio telescope in Chile's Atacama Desert to observe a system of galaxies called CRISTAL-02 as it appeared only 1 billion years after the Big Bang.

With a stellar mass around 10 billion times greater than the sun's, CRISTAL-02 is a galactic merger that represents the latter stages of a multigalaxy collision. It also exhibits an immense plume of gas, almost as long as the galaxy system itself, that is escaping into space at hundreds of miles per second.

This immense outflow, comprising 1.5 billion solar masses, appears to be driven by the intense winds generated through a rapid burst of star formation, as well as star death, the study authors said. Both processes occur as galaxies collide, shocking large gas clouds into birthing new stars, including extremely massive ones that die within a few million years in violent supernova explosions.

The intense radioactive winds released from these young stars and their dying elder siblings can then suppress stellar formation, by energizing and dispersing pockets of cool molecular gas before it can gravitationally collapse to birth baby stars.

"The galaxy has a powerful wind that is ejecting material twice as fast as the galaxy forms stars," first author Rebecca Davies, an astrophysicist at the Swinburne University of Technology in Australia, said in a statement.

The CRISTAL-02 galaxy system may be forming around 260 new solar-mass stars per year — a rate three times higher than galaxies with similar masses and ages. Yet it's also losing more than 500 solar masses per year, — 20 times faster than typical massive galaxies, the researchers found.

"We don’t know much about how the first galaxies stopped forming stars. This work directly shows that process in action," co-author Andreas Faisst, an observational astronomer at Caltech, told Live Science via email.

"If the outflow keeps going, the galaxy will run out of gas to form stars in less than 100 million years from now — a blink of an eye in astrophysical terms."

A widespread cosmic phenomenon

This research offers a blueprint for galactic senescence, or gradual deterioration. "Almost half of early massive galaxies are interacting with other nearby galaxies, suggesting this isn't a quirk but a widespread cosmic phenomenon," Davies added.

But previous simulations have suggested that outflows from active black holes, rather than stars, may be primarily responsible for creating quiescent galaxies. Star-burst-driven outflows cease once star formation stops, whereas black-hole-driven outflows can persist for hundreds of millions of years afterward.

Therefore, the researchers cannot rule out that the CRISTAL-02 outflow was generated by a powerful black hole that was inactive at the time of the observation.

Additionally, the researchers compared the outflow from CRISTAL-02 with a sample of 99 other similar outflows spanning 12 billion years to determine whether this feedback process evolves over time.

They discovered that outflow efficiency has remained roughly constant across cosmic history, even as the internal properties of galaxies have changed while the universe has aged and expanded. Additionally, constraining the early-universe feedback mechanisms that dictate galactic evolution can help astronomers improve cosmological simulations that aim to explain why the cosmos looks and behaves the way it does today.

"If many early galaxies collide and experience rapid growth, then it may not be surprising that we see so many dead galaxies in the early universe," Davies explained. "CRISTAL-02 offers a natural solution to the mystery of why these massive galaxies live fast and die young."

These processes are still at work today, governing local star-dense sectors in our galaxy. They may also dictate its far off future, as the Milky Way could collide with our biggest neighbor, Andromeda, in around 4.5 billion years. When this merger occurs, it "will likely trigger a starburst associated with strong stellar winds — maybe similar to what we see in CRISTAL-02," Faisst said via email.

"The Milky Way and Andromeda system will subsequently likely become a large quiescent elliptical galaxy."

Oil lamps have been simple and popular light sources for more than three millennia. But during the Roman and Byzantine empires, many oil lamps were highly decorated works of art. This hanging lamp in the collection of the Metropolitan Museum of Art was made nearly 1,600 years ago in the shape of a human right foot wearing a sandal, likely as an early Christian symbol.

The bronze oil lamp is significantly smaller than a life-size foot, measuring just 3.25 inches (8.3 centimeters) long. Still attached to the lamp is a chain with a hook for hanging, which is over 17 inches (43.5 cm) long.

The right big toe rests against the spout of the lamp, which would have held the wick. A sandal covers the foot, its leather or cord thongs tied at the ankle. The sole of the sandal is decorated with a swastika, which in Byzantine times was known as a gammadion cross and represented good fortune.

At the back of the lamp, there is an opening at the ankle where the lamp could be filled with oil. The flat cover for the opening is topped with a cross, identifying the lamp as a Christian artifact, Vera Ostoia, a curator of medieval art at The Met, wrote in a 1969 study of objects from the The Met Cloisters.

The foot shape may have been a protective image that symbolized good health and healing, according to The Met, and it may have doubled as a symbol of Christian pilgrimage. But the symbolism may have run even deeper.

In early Christian times, oil lamps and the light they produced were metaphors for enlightenment and immortality rather than just functional, Ostoia wrote. This foot lamp may have been connected to Psalm 119:105, which reads: "Thy word is a lamp unto my feet, and a light unto my path," meaning that people should follow the word of God as their path in life.

For more stunning archaeological discoveries, check out our Astonishing Artifacts archives.

As summer in the U.S. heats up, people become more diligent about protecting their skin from the sun. Another option for doing so will soon be available.

On June 9, 2026, the U.S. Food and Drug Administration approved the first new sunscreen ingredient to be permitted for over-the-counter consumer use in the U.S. since 1999 — a chemical called bemotrizinol.

Bemotrizinol isn't new — consumers in Europe and Asia have used it for decades. Some are hailing its long-overdue approval and arrival onto the U.S. sunscreen scene.

I am a biomedical engineer studying skin science — including the damaging effects of the sun's rays. To understand what bemotrizinol does and how it fits in with products already available to consumers in the U.S., let's take a tour of the physics of sunlight and sunscreens.

A short primer on sunlight

Our planet is irradiated by a yellow dwarf star 93,000,000 miles away that we fondly call the sun. It radiates light from its surface at a temperature of about 10,000 degrees Fahrenheit.

The Earth's atmosphere blocks most of the sun's radiation. Of the rays that get through, about half consist of infrared light — which gives you that warm feeling you feel on a sunny day — and 40% visible light, which you are probably familiar with as daylight.

About 10% of those rays are ultraviolet, or UV, light. UV light has the shortest wavelengths of the three types. That makes it the most dangerous — it's invisible and can damage living tissue.

Ultraviolet damage

Physicists further categorize solar UV light into several types, based on the wavelength, which is measured in nanometers. About 95% of it is UVA (315-400 nm) and 5% is UVB (280-315 nm). Sunscreens need to be able to block those rays from penetrating the skin.

The sun also emits two other types of UV light — UVC (200-280 nm) and vacuum UV (100-200 nm) — but these are stopped by the atmosphere, so sunscreens do not typically need to be able to block them.

Scientists used to think only UVB was harmful because UVB rays cause sunburns. But today, researchers know both types of UV can damage the skin.

UVB, with its shorter wavelength, has more energy, but UVA can penetrate the skin more deeply. And all UV can degrade the integrity of your skin, damage the structure of your DNA and cause skin cancer.

The only natural safeguard your body has against UV light is a microscopically thin layer of a pigment called melanin in your epidermis. The skin produces more melanin when exposed to the sun — that's what tanning is.

This extra melanin does protect the skin, but not fully. That's why protecting your skin with sunscreen is so important.

Sunscreens old and new

Sunscreens come in two different forms — mineral and chemical.

The first chemical sunscreen, developed in 1891, was an ointment made from quinine — a plant-derived compound that makes tonic water bitter.

Chemical sunscreens cover the skin in a transparent coating, acting like a solar sponge. They absorb UV photons and undergo a harmless chemical reaction, then dissipate the energy as heat. Bemotrizinol falls into this category.

Mineral sunscreens such as zinc or titanium oxide ward off the sun's rays by forming a protective film that also absorbs most UV light, but reflects some of it. Unlike chemical sunscreens, the film absorbs the light naturally, without a chemical reaction — which is why they are often visible as a white film on the skin.

Chemical sunscreens that have been available in the U.S until now combine ingredients like avobenzone, the most widely used UVA filter, with UVB filters such as octinoxate, octocrylene octisalate and homosalate. Working together, these substances protect the skin against the broad spectrum of ultraviolet rays.

These sunscreens are only effective for a short time because they are degraded by the chemical reactions they undergo, which means they must be frequently re-applied.

Another important element of sunscreen — whether mineral or chemical — is its Sun Protection Factor, or SPF. This number tells you how well a sunscreen prevents your skin from burning — in other words, what amount of UVB rays it absorbs.

An SPF of 2 would mean a sunscreen cuts your exposure to UVB rays in half, filtering out 50% of those rays. An SPF of 30 means the sunscreen lets just 1/30 of the rays penetrate your skin - which is 3.3%. So it blocks about 97% of the UVB rays.

Dermatologists generally recommend using a sunscreen with an SPF of at least 30.

Benefits of bemotrizonol

Bemotrizinol, while new to the U.S., isn't a new compound. European regulators approved it in 2000. Chances are, if you brought back sunscreen from a vacation in Mexico, Europe, Canada or South Korea, you may even have some laying around your house.

One benefit of bemotrizinol is its ability to filter both UVA and UVB rays, so it doesn’t have to be mixed with other products to do the job.

It has some other beneficial features as well. First, its molecules prefer to sit on the surface of the skin rather than being more readily absorbed into the bloodstream, which can occur for some formulations.

Such absorption has raised concerns that sunscreens might be harmful — though this has not been demonstrated in people, it may discourage some people from using it.

Bemotrizinol also does not degrade as readily in the sun than other chemical sunscreen products. That photostability means it can last for four to eight hours, rather than having to be applied every two hours or so.

Regardless of the type, as a skin scientist I can say with certainty that any sunscreen is better than none. Your skin does an excellent job protecting you from the world outside — so make sure you protect it in return.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

Explosive beams of energy crisscross through rainbow-colored space in a scene that evokes a cinematic sci-fi battle. In reality, it’s a scene of birth; in this single image, astronomers have captured every stage of star formation playing out at once.

This new James Webb Space Telescope (JWST) image reveals OMC-2, a beautiful and dense star-forming region within the Orion Molecular Cloud. It places viewers inside a turbulent cosmic nursery, where gas, dust and newborn stars are all in motion.

Just south of the famous Orion Nebula, one of the best-known stellar nurseries in the night sky (located within the three-star asterism known as the Sword of Orion), OMC-2 is a cloud of cold gas and dust where protostars — very young stars still gathering mass — are forming.

The scene is filled with layered clouds of gas and dust glowing in blue, green and yellow. Thick clumps of cold dust appear dark brown to black, blocking light completely and creating dark pockets across the field. Inside some of these clumps, stars may still be forming, hidden from view inside thick cosmic cocoons.

Scattered throughout the clouds are fully-formed stars of different colors and sizes, from small orange points to larger white and blue stars shining through the haze.

But perhaps the most striking feature of the image is the network of pale, glowing streams and wave-like structures cutting through the cloud. These are created by protostar jets as they collide with the surrounding material, carving out bright ridges and shock fronts. The result is an image that looks sculpted, with curved streams of whitish gas marking how young stars shape their environment.

Each jet, ridge and shadow provides clues about the movement of material through the region and helps astronomers trace how stars form and how their energy changes the surrounding cloud. Its colors and textures reveal a complex environment where gravity pulls material together, young stars ignite and energetic outflows reshape the cloud that gave rise to them.

It’s a vivid portrait of cosmic creation made possible by JWST’s infrared vision, which allows it to peer through thick layers of gas and dust that block visible light. By detecting that infrared light, astronomers can see structures and embryonic stars that would otherwise remain secret.

OMC-2 is one of four parts of the Orion Molecular Cloud, a massive filament behind the Orion Nebula. OMC-1 sits immediately behind the nebula, OMC-2 and OMC-3 are to its north and OMC-4 lies to its south.

See more Space Photos of the Week

The Amazon is the largest rainforest in the world, spanning more than 2 million square miles (5.2 million square kilometers) — an area 12 times the size of California. It influences global water cycles, stores years of global carbon emissions, supports 47 million people, and is home to the greatest concentration of biodiversity on Earth.

But the Amazon rainforest is also disappearing, with 17% of it already cut down or destroyed and largely replaced with agriculture. Other grave threats, such as oil drilling and illegal mining, continue to whittle it down. The next century may have outsize importance, as the forest could reach a "tipping point."

So what will the Amazon rainforest look like in 100 years?

The answer depends on a number of compounding threats, Bernardo Flores, a researcher with the EqualSea Lab at the University of Santiago de Compostela in Spain, told Live Science.

Encroaching farmland and organized crime are a couple of the problems chipping away at the Amazon. But those work in tandem with what he considers the three main threats: climate change, which can lead to extreme weather events, "like wetter wet seasons and drier dry seasons," deforestation and fire.

As the Amazon loses more of its forest, it triggers a feedback loop. "You have less rainfall; then you have less forest, [then] less rainfall, less forest," Flores explained. "That ultimately leads to "a global scale feedback involving the Amazon: More forest loss [leads to] more global warming. More global warming, more forest loss."

As forests get drier, it becomes easier for wildfires to burn more areas. Roads also degrade the forest, and "wherever you have roads, you have people doing illegal activities, illegal logging … then this leads to [more] forest fires," Flores said.

The "arc of deforestation" — a roughly 310,000-square-mile (500,000 square km) border along the Amazon considered the largest deforestation frontier in the world — offers a preview of what much of the Amazon could ultimately look like, according to Flores. The forests that remain there have higher tree mortality and more canopy gaps, and they are often "covered with lianas," or woody vines, that become an ecological problem, he said. Lianas compete with trees for light and nutrients in the soil, and significantly reduce not only a tree's chance of survival but also the overall diversity of trees in a forest. "When the whole forest is covered in lianas, you don't see the forest anymore," he added.

Invasive grasses introduced by cattle farmers will likely proliferate in the decades ahead, but "only a few parts" of the Amazon could become "a savanna, because a savanna is a native, biodiverse ecosystem," he said. Invasive grasses "exclude native species, reduce biodiversity" and would not allow native savanna grasses to replace the forest, Flores said. Instead, one possibility is a "degraded open-canopy ecosystem," where native, naturally fire-tolerant trees, combined with invasive grasses, vines and ferns, proliferate, Flores told Live Science.

Wildlife would quickly be affected as well. Aquatic species are especially vulnerable, Flores said. "When you start having these droughts that will simply last for one, two, three years," wetlands will dry out and become flammable, he explained. That could lead to "very quick extinctions in those areas."

The destruction of the Amazon rainforest would be disastrous for the Indigenous people living there, Christian Poirier, program director of Amazon Watch, an environmental and Indigenous rights advocacy group, told Live Science. "Imagine having your backyard bulldozed and your water source poisoned," he said. "You probably need to move from where you live, and that's exactly what's happening in the Amazon."

A devastated Amazon would also lead to "a more chaotic global climate system," Flores said. There could be less rainfall across parts of South America, and global warming will worsen. Earth could eventually reach a tipping point where ice sheets melt, ocean currents malfunction and the collapse of the Amazon accelerate warming all at once, pushing the planet to "cross the tipping point and transition to a much warmer climate," he said, leading to potentially irreversible consequences.

Unlike other major climate risks, such as the potential of the Greenland Ice Sheet melting and contributing to sea level rise, deforestation can in theory be reversed more easily by reforestation, said Arie Staal, an assistant professor of ecosystem resilience at Utrecht University in the Netherlands.

"That gives us a knob to turn that we don't have for other possible tipping points on Earth," he told Live Science. "It is clear that we really need to stop deforestation in the Amazon. And there's hope."

Rainforest quiz: Can you sort the largest rainforests on Earth?

For most people, a minor cut or scrape is no big deal — the body heals itself quickly, and antibiotics can deal with any infections. But some wounds, such as severe burns and diabetic ulcers, are prone to bacterial infections that can become resistant to antibiotics.

"Diabetic wounds are very difficult to heal and people live with these wounds for pretty much the rest of their life," says Vitaliy Khutoryanskiy, a materials scientist at the University of Reading in the United Kingdom.

To address this problem, scientists are developing new ways to treat infected wounds using specially designed nanomaterials that are activated with light and deliver precise antimicrobial action. The approach has shown promise in reducing infection and accelerating wound healing in experiments on mice and pigs but has not yet been tested in people.

Chronic, non-healing wounds offer ideal conditions for the formation of resilient biofilms, which delay healing and significantly raise the risk of amputation. The vast majority of such wounds — over 78 percent — have these stubborn layers of bacteria, which are often antibiotic-resistant.

The new light-activated nanomaterials offer a different way to eradicate bacterial infections, by converting light into localized heat, or by reacting with oxygen present in the tissues to produce toxic molecules that kill bacteria with minimal damage to the surrounding tissue.

Our skin can naturally absorb tiny amounts of radiation but with the help of specially designed nanomaterials, says Zhenpeng Qin, a materials scientist at the University of Texas at Dallas, "you can heat the tissue to a higher temperature." The heat weakens the bacteria and helps with tissue repair. Qin, who coauthored an exploration of the technique in the 2024 Annual Review of Biomedical Engineering, notes that similar, light-triggered therapies have been used to deliver toxins to target certain skin and esophageal cancers, but they have not been applied extensively to wound care.

In one promising study with wounds, Raffaele Mezzenga, a materials scientist from ETH Zurich, and his colleagues began with a naturally occurring antimicrobial protein called lysozyme, which was extracted from egg whites. They engineered the protein into a gel mixed with a light-absorbing dye. In the presence of near-infrared light, the dye heats up, melting the gel and releasing active lysozyme. When the light is turned off and the material cools, the lysozyme reverts to its inactive form.

When the team applied the gel to wounds in mice and pigs, they found it eradicated more than 95 percent of the bacteria present. The wounds also healed more quickly, because the lysozyme — which is toxic for healthy cells, too — was activated in the wound only when irradiated with light, saving the skin from overexposure. To boost healing still further, the team added magnesium ions to the gel, which prime immune cells called macrophages to shift from an inflammatory state to one that promotes healing. "The healing will be much faster because you kill the bacteria and heal the wound at the same time," says Mezzenga.

Since bacterial biofilms are especially persistent on the surfaces of medical implants — where they can cause recurring infections and sometimes require repeated surgeries or even amputations — the team also tested their gel on infected prosthetic joints in mice. They injected the gel around an infected implanted needle and shone near-infrared light through the skin. The treatment cleared biofilms and eradicated about 99 percent of bacteria around the implant, while preserving bone tissue.

In another recent study, scientists from Gannan Medical University and Shanghai University in China treated wounds using a nanomaterial made of gold nanoparticles and graphene-oxide "quantum dots," which are tiny, carbon-based semiconducting particles. When irradiated with blue light, the gold particles absorb the light energy and convert it into heat, while graphene oxide helps to transfer electrons across the material. This boosts reactions that produce toxic, unstable molecules called reactive oxygen species that react with structures on bacterial membranes and destroy them.

When the scientists added this material to a bacterial solution and shone blue light on it for 10 minutes, the mild heat and reactive oxygen species worked together to cause bacterial membranes to disintegrate. Using a stain that distinguished dead from living bacteria, the researchers confirmed that the treatment had killed 97 percent of the bacteria.

Testing the nanomaterial in mice revealed that after nine days, the wounds on treated mice showed 99 percent healing, while those of untreated mice showed only about 70 percent healing.

While these techniques have shown promise in the lab, further work will be needed before they can be applied to people. "There is still some way to go," says Lars Kaestner, a biologist at Saarland University in Germany. To be useful in a clinical setting, he notes, researchers would need to do extensive safety testing and lower the cost of the nanomaterials.

Nevertheless, the idea provides hope for patients with chronic wounds that fail to heal with conventional antibiotics, particularly as drug-resistant infections become more common in hospitals and diabetic care.

"It's a good concept," says Qin. "Wound healing and antibacterial resistance are very big challenges. And I think any advance that we can make in these areas would be welcome."

This article originally appeared in Knowable Magazine, a nonprofit publication dedicated to making scientific knowledge accessible to all. Sign up for Knowable Magazine's newsletter.

Pets form an important part of many people's lives, providing meaningful companionship. However, our pets can sometimes also be a source of unwelcome pathogens and diseases, particularly if they frequently roam outdoors.

We are ecologists and a veterinarian who study wildlife health and the movement of pathogens among wildlife, domestic animals and people. If you let your cat outdoors, or if outdoor cats visit your yard, our recent findings may be relevant.

Zoonotic pathogens are organisms that can infect both animals and humans. From a pathogen's perspective, humans are just another animal host. Wildlife is often emphasized as a source of emerging disease for humans because there are vastly more wild animal species than domestic animal species.

However, even if a pathogen is capable of infecting people, it needs a way to reach us. Humans share more zoonotic pathogens with domestic animals than with wildlife, because domestic animals live close to us. Pathogens benefit even further if they can infect a companion animal.

In our newly published research, we compiled data from more than 400 studies to investigate how a cat's lifestyle, whether they're mostly indoors, outdoor-roaming or feral, affects that cat's likelihood of carrying pathogens that can infect people.

Across this compilation, there were nearly 100 pathogens detected in cats that are considered zoonotic and capable of infecting humans. Familiar examples are rabies, Toxoplasma gondii, roundworms and Salmonella.

Our research

We found that outdoor-roaming pet cats had three to five times the odds of carrying a zoonotic pathogen compared with indoor-only cats. More surprisingly, cats allowed to roam outdoors had similar odds of carrying at least one zoonotic pathogen as feral cats. Outdoor-owned cats carried fewer types of pathogens than feral cats, but the same pathogens that infect feral cats can also infect owned cats.

These risks become a large-scale problem because pet cats that roam freely interact closely with people, wildlife and other domestic animals. Across the studies we reviewed, about 60 per cent of owned cats had unsupervised outdoor access; in some regions, that rate exceeded 90 per cent.

Roaming cats hunt, interact with wildlife or other domestic animals, and move through environments contaminated with pathogens and toxins. Research suggests that cat owners may underestimate hunting by around 80 per cent, meaning that many prey captures and animal contacts go unnoticed.

These interactions are not uncommon and not limited to so-called pest species. Single-country estimates of wildlife killed by cats run into the billions, with more than 2,000 wildlife species documented as prey for domestic cats.

Cats hunt animals that can carry zoonotic pathogens, including rodents, birds and bats, many of which would otherwise have little direct contact with people. Owned cats might bring home rodents carrying viruses, and there are documented cases of cats bringing rabies-positive bats into homes. A cat returning home with prey can therefore create a pathway by which pathogens circulating in wildlife populations reach people.

In addition, it is not only owners who are at risk. Outdoor cats defecate in gardens, parks, playgrounds and other shared spaces, potentially leading to high contamination rates. One study estimated that outdoor cats deposited more than 60 tonnes [60 tons] of feces per 10,000 households each year.

Depending on the parasite, feces can contain hundreds to hundreds of thousands of parasite eggs that can persist in soil or water for months to years, which can infect people or other animals that come in contact with those eggs.

What cat owners can do

The most straightforward intervention is also the most economical and humane: prevent unsupervised roaming. That does not mean denying cats access to the outdoors. It can mean building "catios" or enclosures, leash walks, supervised time outside or other forms of contained outdoor access.

Veterinary care still matters. Treating existing parasitic infections and vaccinating against diseases like rabies are essential precautions, even for indoor cats. Since neither vaccines nor anti-parasitic treatment cover the full spectrum of wildlife-associated pathogens, managing exposure remains the more comprehensive protective approach.

The free-roaming debate is often framed as a false choice: either cats roam freely, or they are deprived of a natural life. That framing is misleading and inconsistent with how we manage other companion animals.

We do not assume dogs need unrestricted access to roads, neighbors' yards or to hunt wildlife to have good welfare. Indoor cats and cats with supervised outdoor access can live healthy, enriched and longer lives.

Policies and strategies that address how and where owned cats roam outdoors can help safeguard biodiversity, feline and wildlife welfare and public health. That is the central insight of One Health, that the same choices that protect ecosystems can also protect the animals and people who share them.

This article was co-authored by David Lapen, who works for and receives research funding from Agriculture and Agri-Food Canada.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.

How much of a cat fan are you? Find out by taking our cat quiz!

This week's science news was filled with things missing and found, with the revelation of the first-ever deep-sea footage of the elusive goblin shark making waves in the press.

Goblin sharks (Mitsukurina owstoni) are mysterious, deepwater creatures that have not changed much since they first appeared on Earth 125 million years ago — making them "living fossils." But capturing a recording of the sharks in their deep habitats is exceptionally difficult, and they have previously been seen alive only after being hooked to the surface on fishing lines. Scientists recently filmed not one, but two goblin sharks: The first near Jarvis Island in the South Central Pacific, and the second 6,550 feet (1,997 meters) deep in the Tonga Trench.

If you like your elusive animals on the wilier (and certainly much cuter) side, we also reported on the first ever photographs of the dwarf fox, a species that was believed to be extinct but has been found near a highway in Cozumel, Mexico.

Elsewhere, archaeologists found a second cannonball from the 1836 Battle of the Alamo, meaning they now have one from each side of the conflict. And separate teams of archaeologists discovered the remains of a prehistoric man in Germany who may have been a human sacrifice and signs of a "prototype" Stonehenge close near the famous Stone Age monument.

If you got this far wondering if the "missing" news items were, well, missing, we also covered how a "cold blob" of absent heat in the Atlantic Ocean is shifting Indian summer monsoons, threatening over one billion people; the Texas-size chunk of ice missing from Antarctica; how an ancient chunk of the moon found in Africa hints at a calamitous lunar collision; and a bizarre viral infection that left a woman unable to recognize her own father.

California is scarily close to a major quake

'The system is critically stressed': San Andreas and San Jacinto faults scarily close to major earthquake, study finds

The next major Californian earthquake could be closer than we thought, according to an alarming new study.

The research, based on historical modeling of earthquake activity, found that Southern California's San Andreas and San Jacinto fault systems are at their highest levels of tectonic stress in more than 1,000 years; while also being connected by a "gate" system that could make them rupture together.

The exact odds of each event happening and the timing of a possible future rupture are unknown. But the scientists stress that understanding how much strain is building up inside the system could help to prepare for whatever comes next.

Life's Little Mysteries

Why does it take our eyes so long to adjust to the dark?

Our eyes are remarkably adaptable, switching from navigating under bright lights to the near pitch-black of a moonless night. But anyone who's stubbed a toe during this acclimation window — and that definitely includes me — may have once or twice asked themselves why it takes our eyes so long to adjust to the dark. Live Science shed a bit of light on the question.

—If you enjoyed this, sign up for our Life's Little Mysteries newsletter

Physicists split a photon

'A mixture from zero to infinity': Physicists split apart a photon — and ended up with an improbable swarm of particles

What do you get if you split a photon? Anywhere from zero to an infinite number of more photons, physicists say.

That's the finding made by a new experiment that simulated a photon being sliced by a shutter under various circumstances, revealing the result was anywhere from zero to one to upwards of an infinite swarm of the tiny light particles. The probability of each of these states corresponded to how quickly the shutter cut the photon.

And the unexpected behavior has some truly profound implications for how we view fundamental particles.

Discover more physics news

—The world's first nuclear clock just ticked on — and it could help detect a fifth fundamental force of physics

—NASA's experimental X-59 jet breaks sound barrier twice, reaching Mach 1.4 in step toward 'quiet supersonic' technology

—Earth-based telescope shares image of Artemis II capsule near the moon — one of the farthest photos of humans ever taken

Also in science news this week

—'A completely different story': 300 million-year-old fossils reveal the first vertebrate land dwellers weren't what we thought, researchers claim

—Oldest known plague victims found in a 5,500-year-old burial ground in Siberia — and many of them were children

—Indonesia's near-identical, 'Twin Peaks' volcanoes form striking mirror image — Earth from space

—Lavish Roman villa discovered outside Rome's walls may have been frequented by Hadrian and Marcus Aurelius

—Neuroscientists are searching for the 'cellular substrate of loneliness'

Science Spotlight

'River in the Sky': China's doomed plan to create a 'cloud seeding corridor' tells us how far the country will go to solve its climate crisis

China's response to the climate crisis continues to astonish. Over the past two decades, the world's industrial powerhouse has presided over the largest and fastest clean energy buildout in modern history, while also working to bring its carbon emissions to a peak before 2030.

But an underdiscussed aspect of China's climate plans are its bold attempts to geoengineer the environment to be more resilient and better suit human needs. That's why, in his three-part "Taming Nature" series, Live Science's production editor James Price investigated the country's efforts to create a permanent atmospheric river and build the world's biggest dam in earthquake-prone Tibet.

Something for the weekend

If you're looking for things to keep you busy over the weekend, here are some of the best news analyses, crosswords, interviews, opinion pieces and quizzes published this week.

—A secretive Chinese probe has just arrived at one of Earth's 'quasi-moons' and will soon attempt a first-of-its-kind landing [News analysis]

—Dangerously hot and humid: Rising temperatures in the US make outdoor exercise hazardous [News analysis]

—'Is having two legs useful' in space?: Astronaut John McFall explains what life in orbit might be like for the first physically disabled person in space [Interview]

—'They reliably chose the statistically more favorable option': A crow researcher explains how these winged geniuses process numbers, and what it could reveal about human math smarts [Interview]

—Bow-Wow, Ding-Dong, Pooh-Pooh: Expert explains early theories of how human language evolved — and their silly names [Opinion]

—Rainforest quiz: Can you sort Earth's largest rainforests from biggest to smallest? [Quiz]

—Live Science crossword puzzle #48: Largest fish on Earth — 6 across [Crossword]

Science video of the week

Watch bison herd defend a newborn calf from wolf attack in a primeval Polish forest

European bison (Bison bonasus) are typically considered to be a non-prey species — only being hunted by humans.

But rare and unexpected camera trap footage from Poland's Bialowieza Primeval Forest (the oldest and best-preserved temperate lowland forest in Europe) has called that into question.

In the video, a herd of bison is recorded rallying around a newborn calf to fend off an attack from five wolves (Canis lupus), successfully driving the predators away. It's a nerve wracking watch, and one that could become more common as wolf packs grow in size thanks to a late 1980s hunting ban across the region.

Follow Live Science on social media

Want more science news? Follow our Live Science WhatsApp Channel for the latest discoveries as they happen. It's the best way to get our expert reporting on the go, but if you don't use WhatsApp we're also on Facebook, X (formerly Twitter), Flipboard, Instagram, TikTok, Bluesky and LinkedIn.

The patient: A 31-year old man in Louisiana

The symptoms: When the patient reached the hospital, he was bleeding from the mouth and had severe neck pain and stiffness. Upon examining the man, his doctors noted a tear in the back of his throat on the right side.

What happened next: The man, a sports fisherman, had been brought to the hospital by boat and helicopter after an accident during an ocean fishing trip. He had caught a white marlin (Kajikia albida), a type of large fish with a long pointy "bill," weighing approximately 60 pounds (27 kilograms). This species can grow up to 180 pounds (82 kg).

As the man leaned over the side of the boat to release the hook from the fish, it jumped and struck him in the mouth with its bill, sending the man tumbling backward into the boat. He felt pain in his neck, which then radiated into his spine.

At the hospital, an X-ray of the man's upper spine did not reveal any abnormalities. However, his intensifying spinal pain and neck stiffness prompted one of the doctors to order a computed tomography (CT) scan of the same area. In the CT scan, physicians noted "a wedge-shaped, hyperdense object," they wrote in a report of the case. The object had penetrated the back of the man's throat and entered his spinal canal. It stuck there, piercing the foramen magnum — a large hole at the base of the skull that the spinal cord passes through.

The diagnosis: The doctors immediately performed surgery on the man to remove the penetrating object. They administered general anesthesia, and the surgeon used retractors — instruments that hold wounds open — to expose the object, which turned out to be the broken tip of a fish bill.

The treatment: The sharp bill fragment was so firmly wedged in the man's skull that the surgeon had to make an additional incision above the man's topmost vertebra in order to remove it, pulling it out along the path of entry. It measured about 1.4 inches (3.5 centimeters) long.

After the fragment was removed, the patient was given five different types of antibiotics both to prevent infection from microbes found in the throat and from bacteria that are unique to marine environments. He was discharged eight days later and continued to take multiple antibiotics for the next two weeks.

At his final follow-up visit, the man had fully recovered and showed no lingering neurological symptoms.

What makes the case unique: In 1848, doctors published the first medical case study of a skull injury from a foreign object: a gunpowder explosion had sent an iron bar through the skull of railroad worker Phineas Gage. Gage recovered, but he exhibited personality changes that doctors attributed to his significant brain injuries.

In another notable case, published in 1895, a man had tripped and fallen face-first onto an oilcan. The spout penetrated his cheek and became stuck at the base of his skull, causing temporary incontinence and permanent memory loss.

Since those 19th-century cases, physicians have reported instances of cranial trauma in different parts of the skull and from a variety of objects, including a crochet hook, a pitchfork, a bike key and a harpoon.

This man's case is the first reported instance of an injury to the foramen magnum, as well as the first injury caused by a fish bill, according to the report.

This article is for informational purposes only and is not meant to offer medical advice.

It's after dark, and the lights go out; a thunderstorm has knocked out your power. At first, it's pitch-black. But slowly, after a while, the light from the moon makes it possible to see your surroundings. The light didn't change; your eyes did.

But why does it take our eyes so long to fully adjust to the dark?

It has to do with the types of cells in the eye and how they evolved, experts told Live Science.

Our eyes use two kinds of cells to sense light. These cells, known as photoreceptors, are called rods and cones, based on their shapes, Alapakkam Sampath, a retinal neuroscientist at UCLA, told Live Science.

Cones are responsible for color vision. Humans possess three kinds of cone cells, which detect red, green or blue light. The colors people can see are a mix of red, green and blue, Anand Swaroop, chief of the Neurobiology Neurodegeneration & Repair Laboratory at the National Eye Institute, told Live Science.

Rods cannot discriminate colors, but they are far more sensitive to light. Each is capable of detecting a single photon, or particle of light. "Rods are what allow you to see in dim light," Swaroop said.

The extraordinary sensitivity of rods has a price, though: Once each rod detects a photon, it can take up to an hour for it to regenerate its ability to see light, Johan Pahlberg, chief of the photoreceptor physiology group at the National Eye Institute, told Live Science.

The compound that helps rods sense light is called rhodopsin, which is derived from vitamin A, Sampath said. Once each rhodopsin molecule absorbs light, it gets "bleached," meaning it can no longer detect light.

Specifically, rhodopsin is made of two compounds: opsin and retinal, Pahlberg said. When rhodopsin absorbs light, the retinal changes from bent to straight and detaches from the opsin. This retinal eventually makes its way into a part of the eye known as the retinal pigment epithelium, where it can get repaired and resume a bent shape. This retinal can then make its way back to an opsin and reattach to create a functional rhodopsin.

If all of the rods in a human eye are bleached, it may take 45 minutes to an hour for all of them to regenerate, Pahlberg said. However, some rods may regenerate within 10 to 15 minutes to grant some level of vision in dim light, he added.

Rods and cones line the retina, the back part of the eyeball. Rods outnumber cones in most mammal retinas. "In each human eye, there are roughly 6 million cones and 100 million rods," Swaroop said. Sampath noted that "since it takes a lot of time for rods to regenerate, your eyes have a huge number of them to compensate."

Cones are found mostly in the center of the retina, where the eye's lens focuses most of the light it receives, while rods dominate the rest of the retina, Sampath explained. This reflects how during the day, we rely mostly on cone cells for our vision. "Rods are mostly not functional at all during that time," he said.

The human eye does have a quicker way to adjust somewhat to the dark. It can enlarge the pupil, the dark hole at the front of the eye, to let in more light, explained Mark Fairchild, professor of color science at the Rochester Institute of Technology in New York, in an article in The Conversation. However, the vast majority of the eye's adaptation to darkness is due to its rods, and the long amount of time it takes for rods to regenerate explains why it takes so long for eyes to fully adapt to the dark.

Before artificial lighting, humans would typically not experience quick shifts from light to dark. Instead, the ability for human eyes to adapt to the dark would have relied on the setting of the sun, which might take about the same time as rod cells take to regenerate. "There was no evolutionary pressure for it to be faster," Sampath said.

Rods are the most vulnerable cells in the retina to disease and dysfunction, Pahlberg said. This is why older adults often have trouble driving at night. "My colleagues are developing a diagnostic test as a normal part of an eye exam to measure the human adaptation to the dark to see how it changes with age," Sampath noted.

A camera trap in an ancient Polish forest has captured extremely rare and unexpected footage of wolves attacking a bison herd made up of adults, youngsters and a newborn calf, a new study shows.

The event took place on Sept. 15, 2025. Five wolves (Canis lupus) enter the camera frame, closely followed by three bison cows and the newborn calf. In the footage, the cows chase after the wolves, leaving the calf alone and exposed. The wolves then surround the calf, bite its neck and try to drag it away, but two cows come to its rescue. The wolves return and seize the calf a second time in the background of the video — however, this time the entire bison herd comes to its defense to end the attack.

The clip is from the Bialowieza Primeval Forest, the oldest and best-preserved temperate lowland forest in Europe, which hosts the world's biggest population of European bison (Bison bonasus). The forest covers 350,600 acres (141,900 hectares) on the border between Poland and Belarus. There are more than 870 bison on the Polish side, according to the new study, while the Belarussian side has roughly 730 bison.

Also known as "the king of the forest," the European bison is typically considered a non-prey species, meaning it has no predators except humans. But the footage calls this into question.

"To our knowledge, we present the first video-recorded evidence of wolves attacking a European bison herd in the Białowieża Primaeval Forest," researchers wrote in the study, published May 29 in the journal Ecology and Evolution. "Although the video did not capture a direct kill, it suggests that other attacks on European bison could potentially be successful."

Historical documents show that wolf attacks on European bison used to be more common, with about 8 kills recorded annually in the Bialowieza Primeval Forest between 1840 and 1849. The forest was a popular hunting ground for monarchs from the 14th century onward, explaining why such detailed records exist.

European bison went extinct in the wild in 1919, but they were reintroduced in the Bialowieza Primeval Forest in 1952. The first confirmed bison kill since then dates to the mid 1990s, and after that, it seems as though wolves stuck to a diet of roe deer (Capreolus capreolus), red deer (Cervus elaphus) and wild boar (Sus scrofa), likely because these are much easier prey than bison, the researchers wrote in the study.

But now, "our observation demonstrated that the European bison is in fact a potential prey for wolves," they wrote. "This raises questions about why predation attempts are so rare, whether the bison can still be described as a non-prey species, and what this could mean for conservation and management of the species."

An intriguing trend in the Bialowieza Primeval Forest is that wolf packs are growing in size, possibly thanks to a late 1980s hunting ban. This shift could increase wolf predation on bison in the future, because bigger packs can handle bigger prey.

"If predation on European bison, specifically young animals, occurs more frequently than previously assumed, wolves could play a small but potentially important role in the natural regulation of bison numbers," the researchers wrote in the study. "In turn, such regulation could possibly lead to mitigation of human-bison conflicts."

High estrogen in the brain's memory center may worsen one's resilience against traumatic events, swaying the tendency to develop memory problems or post-traumatic stress in the aftermath, a recent study in mice suggests.

The research, published in April in the journal Neuron, explored the effects of estrogen in the mouse brain. It zoomed in on the hippocampus, a key part of the brain involved in learning and memory. Both male and female mammals produce significant amounts of estrogen in the hippocampus, despite it often being framed as a "female" hormone.

"We're so biased to think of female high estrogen, male low estrogen," said study co-author Elizabeth Heller, an associate professor of pharmacology at the University of Pennsylvania Perelman School of Medicine. But "in this local brain region, where you have local production of estrogen, actually sometimes the males are higher than the females depending on the female's cycling," Heller told Live Science. Estrogen levels in the female hippocampus rise and fall in line with the body-wide hormone cycle, while its levels in the male hippocampus remain fairly steady.

The study suggests that these local estrogen concentrations may influence one's vulnerability to memory problems following major acute stress. Although the research was conducted in mice, the authors think it likely has relevance to humans.

"I think this is highly translatable," study senior author Dr. Tallie Z. Baram, a professor, developmental neuroscientist and child neurologist at the University of California, Irvine, told Live Science.

Estrogen isn't always a memory booster

Traumatic experiences can cause memory disturbances, including difficulty remembering specific personal experiences and having fearful reactions to formerly safe, familiar situations. When these issues persist and are accompanied by intrusive memories of the traumatic event, they are classified as post-traumatic stress disorder (PTSD).

About 10% to 12% of women experience PTSD in their lifetime, compared with 5% to 6% of men. Some of that difference may stem from variance in men's and women's lived experiences; for instance, women have higher rates of sexual assault at young ages than men do. Biological differences between women and men are another potential factor, but their contribution to the phenomenon is poorly understood.

The new study highlights hippocampal estrogen as one difference that might matter. "The research has uncovered important new avenues for research on PTSD," Victoria Luine, a professor emerita of psychology at Hunter College in New York City who wasn't involved in the work, told Live Science in an email.

In the study, researchers simulated acute traumatic events by exposing lab mice to multiple stressors at the same time, including bright lights, loud music and the odors of other stressed-out mice. They ran the mice through various memory tests before and after the stressful experience and compared these rodents with a group that did not experience such stressors.

Compared with unstressed mice, the stressed-out male mice performed worse on the various memory tests, and those deficits persisted for weeks. "Even a month later, they had a memory deficit — so it's a really perseverative effect," Heller said.

A similar pattern was seen in female mice that were stressed out during proestrus, the phase of their hormone cycle when estrogen peaks and the body prepares for ovulation. Both sets of mice learned to associate certain cues with the stressful experience and avoid them, with females being more sensitive to those cues than males were.

But interestingly, female mice that were stressed during estrus, when estrogen plummets and ovulation occurs, showed resilience. Their behavior and memory remained comparable to those of unstressed mice. "The female mice that had low levels of estrogen laughed it off — they were completely protected," Baram said.

Studies suggest hippocampal estrogen levels are similar in male and proestrus female mice, while estrus females have lower levels. The researchers confirmed this using a technique called mass spectrometry, finding that estrus mice had half the amount of hippocampal estrogen that the males and proestrus females did.

In this context, that lack of estrogen in the hippocampus appeared to guard against the negative effects of stress. This finding was surprising, Baram noted, because estrogen is generally thought to promote memory function in both sexes and declines in estrogen, as seen during menopause, are tied to memory problems. That said, menopause takes place over a much longer timeline than the female mouse hormone cycle, which takes only four or five days.

A connection to DNA

Why do estrogen levels matter for memory? "Estrogen receptors directly control gene expression," Heller said. By binding to its receptors, estrogen turns the activity of certain genes up or down.

Heller's lab studies mechanisms that control gene activity in the context of psychiatric disorders. One of those mechanisms is chromatin remodeling, meaning changes in how DNA is packaged in a cell that can shift which genes can be activated at a given time. A portion of the chromatin can be "open," exposing genes to machinery that turns them on, or "closed," which typically shuts genes down.

It turns out that the high hippocampal estrogen in male mice and proestrus female mice opens up their chromatin in a way that might leave them vulnerable to memory issues ushered by severe stress. Female mice in estrus, by contrast, have a totally distinct chromatin profile that appears to be protective.

"We can see that the function of many of those [open] genes relates to synapse biology," Heller said. Synapses are the points at which different neurons meet and exchange electrical signals, and they're central to the physical structure of memories in the brain.

It may be that, in most circumstances, it's useful to have high levels of hippocampal estrogen because they "open" the chromatin, enabling the hippocampus to forge new memories quickly in response to new experiences, Baram noted. But when these experiences consist of severe acute stress, "that same plasticity, that same ability of the brain to learn, turns problematic," she said. If the results carry over to humans, women may be particularly vulnerable to these memory impacts in certain phases of their menstrual cycles or points in their lifespans when estrogen is high.

In males and females, different flavors of estrogen receptor were responsible for the stress-induced memory issues. The reasons for this difference will be a matter of future study, Baram said. Additionally, future research could attempt to pinpoint exactly where the different estrogen receptors are located throughout the hippocampus, Heller said.

The study provides a "strong demonstration that estrogens drive sex-dependent, stress-induced changes in chromatin networks which can dramatically alter neural functions like memory," Luine said. What's more, "these results present cogent evidence that sex is a powerful biological variable."

Historically, female lab animals were excluded from studies because it was thought that their hormone cycles were too complex and would muck up the findings. The field of neuroscience exemplified this trend. In recent years, the U.S. National Institutes of Health (NIH) has required that scientists take sex differences into account when designing NIH-funded human and animal studies, but progress has been slow on both fronts — and current federal leadership has signaled a lack of support for the initiative.

It's important to include both sexes in research to truly understand how the brain functions and responds to external factors, like stress, Luine said. "An important aim of this and other studies is to protect humans against PTSD," she added, and this study strongly suggests preventive treatments for PTSD might need to be tailored by sex.

Beyond PTSD, Baram thinks the research could have implications for women's risk of aging-related memory problems and dementia.

The decline of estrogen in menopause is thought to raise this risk, but prior to menopause comes perimenopause — a period with massive spikes in estrogen. The study's findings hint that if stress shows up during perimenopause, the combination of stress and high estrogen levels may contribute to memory problems. Thus, perimenopause may represent another time when women are particularly vulnerable to memory disturbances, Baram suggested.

"We need to start thinking a little bit differently," she said. "What is it about women at that stage in life that makes them more vulnerable to memory loss with aging?"

This article is for informational purposes only and is not meant to offer medical advice.

This article was first published May 4, 2026.

See how much you know about the most complex organ in the human body with our brain quiz!

Never-before-seen fossils of newly hatched crocodile-like creatures are shining new light on how our aquatic ancestors conquered land.

Early four-limbed vertebrates (tetrapods), which would eventually give rise to humans, took their first steps on land in the Devonian period, some 419 million to 359 million years ago, marking one of the most important periods in the evolutionary history of animals.

Now, a new study published Thursday (June 18) in the journal Science has revealed that these early tetrapods were less like amphibians and more like us. Rather than having a tadpole phase in their development, as many amphibians do today, new evidence suggests that they were direct developers — growing from smaller to bigger versions of themselves, like their ancestors, humans and many other animals.

The study is an important contribution to our understanding of early tetrapods' reproductive developmental biology, said Tim Smithson, a visiting academic at the University of Cambridge who specializes in early tetrapods but was not involved in the study.

It suggests that the "earliest tetrapods that took those first steps on to land were able to rely on the successful reproductive and developmental strategies of their forebears," Smithson told Live Science in an email. "Direct development made life easier — one less thing to worry about!"

The new research was based partly on fossils from early land-dwelling predators called embolomeres. These animals looked like a cross between a crocodile and an eel and ruled river, lake and swamp habitats 350 million to 280 million years ago, during the Carboniferous and Permian periods. While these creatures could grow to more than 10 feet (3 meters) long as adults, the study unveils rare fossils from Mazon Creek, near Chicago, that preserved embolomeres as hatchlings that were days to a couple of weeks old.

"These are intimate details of the first moments of these animals' lives, and we've never seen that before for this entire part of the evolutionary tree," study co-author Jason Pardo, a postdoctoral fellow of evolutionary biology at Vilnius University in Lithuania and a research associate at the Field Museum in Chicago, told Live Science.

These fossils didn't show evidence of external gills and other tadpole-like features that the researchers would have expected from an early land dweller. The researchers then checked other fossils from before and during the "fin-to-limb transition" but found no evidence of an amphibian-like life cycle in those, either.

"For as long as we've understood evolution, we've assumed this story of how we made that transition from water to land," Pardo said. "We in fact have a completely different story."

Science upended?

A statement released by the Field Museum claimed that the study upends scientists' understanding of how animals conquered the land. However, the experts Live Science spoke to disagreed with this assertion.

"The Mazon Creek material is wonderful, the study is interesting and the interpretation of the fossils is sound, but I don't think the results are terribly surprising," Per Ahlberg, a professor of evolutionary organismal biology at Uppsala University in Sweden, told Live Science in an email.

Ahlberg, who was not involved in the new study, specializes in the early evolution of tetrapods. He noted that scientists knew some early tetrapods had a larval stage similar to that of modern salamanders ‪—‬ namely, those belonging to the group Temnospondyli, which he described as the ancestral stock of modern amphibians. However, he contends that this didn't mean scientists assumed every early tetrapod was the same.

"Nobody has been arguing in recent years that ALL early tetrapods had such a larval stage or that this was essential for enabling the transition to land," Ahlberg said. "I mean, I have been working right at the core of this research field for 40 years and I have never given it any thought."

In response, Pardo agreed that specialists in the field recognized that the data didn't support that early tetrapods had an amphibian-like development. However, he argued that even among specialists, assumptions were still made about metamorphosis — a major developmental transition, like a tadpole transforming into a frog — and amphibian-like bodies.

"Onto something big"

Study co-author Arjan Mann, an assistant curator of early tetrapods at the Field Museum, first saw the study's first baby embolomere fossil during a 2016 trip to the Field Museum while working on his doctorate. At the time, the fossil was a mystery.

Mann and Pardo mused over the fossil's identity for years before high-resolution scans with scanning electron microscopy at the Canadian Museum of Nature confirmed that the ancient creature was an embolomere, according to the museum's statement.

"I think Jason and I both knew we were onto something big, since fossils of this kind of animal and from this phase, and developmental state in early tetrapod evolution have never been found or studied before," Mann told Live Science in an email.

Along with the embolomeres, the researchers looked at megalichthyid fish from before the land transition and limbless, snake-like creatures known as aistopods from during the land transition. All showed signs of direct development, they said.

"I think the take home message of this study is that we should always challenge conventional wisdom in science, especially when these older ideas do not have substantial backing," Mann said.

Some people from Oceania harbor thousands of genetic variants inherited from the Denisovans ‪—‬ a mysterious group of extinct humans ‪—‬ that are still active in their immune systems today, a new study finds.

The findings, published June 11 in the journal Science, come from the largest-ever map of Denisovan-inherited DNA ever created. The discovery shows that Denisovan DNA "is not just a remnant of ancient liaisons; it continues to influence our biology today," study co-author Serena Tucci, an assistant professor of anthropology and head of the Human Evolutionary Genomics Laboratory at Yale University, said in a statement.

Experiments revealed 3,127 variants inherited from Denisovans that still function in the immune systems of modern-day people; some of these variants switch genes that turn the immune response on or off, according to the new research.

However, because many of the immune system genes identified also affect other bodily functions, it is unclear exactly how these genes benefited survival, study first author Patrick Reilly, an evolutionary genomics researcher at Yale, told Live Science.

Denisovan DNA is active in humans today

Previous research has already found that some modern-day people in Oceania ‪—‬ a region that includes New Guinea, the Solomon Islands and Fiji ‪—‬ have some Denisovan DNA. For example, people from Papua New Guinea are known to carry up to 5% Denisovan DNA in their genomes thanks to prehistoric trysts with the enigmatic group of humans who lived in Asia and disappeared around 30,000 years ago. This is among the highest proportion in the world, with modern-day East Asians typically carrying only around 0.1% Denisovan DNA.

Previous research has also shown that modern-day Tibetans carry a Denisovan version of the EPAS1 gene that supports their adaptation to living at high altitudes. People living in the highlands and lowlands of Papua New Guinea have different Denisovan gene variants depending on their local environments.

Yet Oceanians are vastly underrepresented in genomic databases. Sequencing the genomes of Oceanians can give a glimpse into the lives of the Denisovans and is essential for closing gaps in health disparities in Pacific Islanders as a whole, Reilly said.

To fill this gap, Tucci and her team sequenced the genomes of 177 Oceanians from 12 populations and compared them to 1,284 previously published genomes from populations worldwide. Then, they compared these segments to the known Denisovan genome and three Neanderthal genomes.

Combined, the team built a catalog containing three times more Denisovan genetic sequences inherited from Denisovans than were previously identified, over 70% of which were unique to Oceanians.

Natural selection increased the frequency of some of these variants in people from Near Oceania, which includes New Guinea, the Bismarck Archipelago and the Solomon Islands in the Pacific Ocean, including genes linked to bone development, metabolism and fertility.

The team also ran experiments to assess whether any of the Densiovan DNA was changing how genes behaved in these populations, Reilly said.

This revealed that Denisovan genetic variants can switch various immune system genes on or off, although the exact immune functions that were targeted varied among the Oceanic populations studied.

Early migrants to Oceania at least 42,000 years ago benefited from Denisovan genes when they entered their new environment and encountered new disease-causing pathogens, Reilly said.

"This is consistent with multiple independent instances of local adaptation in response to novel immune environments and pathogens during human dispersal into the Pacific," the authors wrote in the study.

Although the researchers don't know exactly why natural selection acted on these genes, the findings highlight the major role pathogens played in shaping the way humans and our extinct relatives evolved, Reilly said.

The research is an "outstanding effort to try to understand the biological implications" of the enduring Denisovan genetic variants, Mathilde André, an evolutionary geneticist at the Pasteur Institute in France who was not involved in the study, told Live Science in an email.

The tripling of known Denisovan-inherited genetic sequences, most of which are unique to Oceanians, highlights the need to sequence the genomes from previously unrepresented populations to capture the diversity of Denisovan DNA, André said.

See how much you know about early humans with our human evolution quiz!

Camera traps from inside the Chernobyl exclusion zone reveal how the occupation of Russian forces at the site in February and March 2022 altered the behavior of wildlife living in the area.

After the invasion, which involved significant armed conflict inside the exclusion zone, mammals like deer and horses became less active and spent less time moving around at night, a new study reports.

Researchers discovered the changes by comparing footage from camera traps collected during the early months of Russia's 2022 invasion with recordings from the same period a year earlier, before the conflict began. The findings, published Thursday (June 18) in the journal Science, offer a rare glimpse of how animals respond to the immediate disruption caused by warfare.

"I wish the opportunity to analyze how the unfolding invasion affected wildlife ha[d] never happened," Svitlana Kudrenko, who conducted the study as part of her PhD at the Albert Ludwig University of Freiburg in Germany, told Live Science in an email. "Unlike in preindustrial times, current interstate conflicts are highly detrimental for wildlife because of a long list of warfare, often operated remotely."

The study took place in the Chernobyl exclusion zone, a roughly 1,000-square-mile (2,600 square kilometers) area surrounding the site of the 1986 Chernobyl nuclear disaster. Following the reactor explosion, authorities evacuated the region and restricted most human activity. Over the decades, with little to no human activity, wildlife populations have flourished, turning the zone into a natural laboratory for scientists studying ecosystem recovery and animal behavior.

But in February 2022, Russian forces seized control of the region during the beginning stages of the invasion of Ukraine. Military vehicles, troop movements, weapons being fired and other wartime disturbances suddenly transformed one of Europe's most unusual wildlife refuges into an active war zone.

To investigate the impact, researchers analyzed data from camera traps already operating in the exclusion zone from 2020 to 2022. Studying the ecological effects of armed conflict is difficult because war zones are dangerous and often hard for researchers to access.

By using the existing network of automated cameras, the scientists captured wildlife responses that would have been impossible to record otherwise. In total, the team analyzed almost 2,000 photographs and videos from the exclusion zone to build a picture of behavioral changes in response to the conflict.

The images and footage revealed responses from 11 wild mammal species, ‪showing that some animals changed their behavior during periods of heavier fighting.

Several mammal species — including roe deer (Capreolus capreolus), red deer (Cervus elaphus), moose (Alces alces) and red foxes (Vulpes vulpes) — were less active during the occupation than before the conflict, especially at night, the team reported.

The findings suggest that the impact of conflict can ripple through entire ecosystems. While Russia no longer occupies the Chernobyl exclusion zone, the authors highlighted that this study still shows how animal behavior can adapt to warfare.

Camera traps could become a valuable tool for measuring the environmental costs of conflict and understanding how wildlife copes with sudden human disturbances across the globe, the researchers added.

"Our study highlights the need to develop and implement research and conservation strategies focusing on armed conflict impacts on wildlife and environment in general, especially in areas of conservation importance," Kudrenko said.

What do you know about the animal kingdom? Test your knowledge with our animal quiz!

Energy used to power artificial intelligence (AI) could jump to 3% of global electricity demand by 2030, guzzling as much water as the 1.3 billion people in sub-Saharan Africa consume in one year to meet their domestic water needs.

Those are the conclusions of a recent United Nations report that estimated the land use, water consumption and greenhouse gas emissions associated with AI's breakneck expansion. If the data centers that underpin AI formed a country, they would rank 11th in the world for energy use due to their high infrastructure and electricity needs to train ever more complicated models and satisfy users, the report found.

By 2030, data centers could rise to sixth in the world for energy consumption, which would have a land footprint the size of Connecticut and release emissions comparable to those of the U.K. in 2025, depending on how much renewable energy is in the mix.

The findings highlight how much additional pressure AI and the infrastructure that supports it could put on the environment and the climate within the next few years. But why does AI have such a huge footprint, who is benefiting or being left out from the opportunities linked to AI's growth, and what can be done to limit the damage?

To find out more, we spoke with Kaveh Madani, lead investigator for the U.N. report; director of the United Nations University Institute for Water, Environment and Health; and the recipient of this year's Stockholm Water Prize.

Sascha Pare: What would you say is the main takeaway from the report?

Kaveh Madani: The main takeaway of this report is that although in the general discourse AI is perceived as something virtual, or digital, or up in the clouds, there is [a] massive physicality to AI and the supply chains and infrastructure that back it up. And that's one thing that this report has tried to do: to remind people that behind every prompt, every use, every interaction, there is some level of impact on the environment. This is because from the top of the supply chain, where the extraction of critical minerals happens, to the point of manufacturing the hardware, the construction of the data centers, then the operation of data centers, and then dealing with the e-waste, there are major environmental impacts. If we take all of those into account, then we realize that what's digital is not necessarily free of impact. There is always some footprint associated with it, and we have to remember that.

SP: Why does AI have such massive land and water footprints, specifically?

KM: The report outlines the carbon, water and land footprints of AI's energy use. All along the supply chain, from the extraction of critical minerals to the point of disposing and dealing with the electronic waste, we have actions and interventions that require water, require land, and are associated with carbon emissions. So, if you think about, for example, the extraction of critical minerals, we know that during the process, a lot of water is being used and a lot of water is being polluted and poisoned. We published a report in April about the water injustice implications of the critical minerals, showing exactly what is happening where we have the extraction of critical minerals.

But let's not forget that the [new] report is focused on AI's energy use, and then tries to argue that the energy production process itself requires also a lot of water and land. If you are using hydropower to provide energy to your data center, you're using a lot of land and a lot of water. This applies to all sorts of energy sources, regardless of being clean or not, or if you consider them renewable or not — they all require water and land. On top of this, of course, you need to build data centers on land, but also you need water for cooling. That's why, throughout the supply chain, throughout the life cycle of AI, we have a lot of water and land use, in addition to carbon emissions.

SP: The report is packed with jaw-dropping statistics about how big AI's environmental footprint could get by 2030. But how significant are the impacts?

KM: First of all, it is very hard to estimate exactly how much energy AI is currently using, but we know that roughly 20% of the current load of data centers can be attributed to AI. We are expecting that to be 40% within a few years. And by then, the data centers that back AI's operations are expected to have an energy demand that is about 3% of the total energy demand of the world. This is equivalent to being the sixth-most-energy-intensive country in the world. The water demand of that is also huge; the water footprint associated with that is enough to satisfy the domestic water needs of 1.3 billion people in sub-Saharan Africa.

SP: Can the environment and communities cope with the projected levels of energy and water consumption needed for AI?

KM: There would be places in the world where big decisions must be made, meaning that you have to decide if you want to continue using your water for agriculture or if you want to put it into data centers. Those would be decisions for the communities — and if the communities are not involved, then the most vulnerable, the poor, will be dealing with the consequences.

At the same time, we know that the world's electricity consumption keeps increasing. That's a major problem, because although we are trying to add more and more renewables to the energy supply systems, the renewables cannot keep up with the increasing electricity demand. This means that not only can we not retire the old systems, but we might also need to use more fossil energy to satisfy this growing demand. And of course, that means more pressure on the fragile environment.

We know some of the data centers are being placed in locations that are already dry or suffering from what we refer to as "water bankruptcy," based on the report we published in January. These are major issues. More pressure on the environment [puts] more pressure on humans, and this recipe means [we could have] a kind of reinforcing degradation loop that would jeopardize both nature and human society.

SP: Who is benefiting the most from AI's expansion, and who is being excluded?

KM: AI expansion is benefiting humanity as a whole. It has changed our lifestyle; it has provided a lot of opportunities and improvements. But at the same time, it has some consequences. The issue that we see right now is that the richer communities and countries of the world are the ones that are benefiting from it the most, and within those communities and countries, it's the rich who are also profiting more from the expansion. If you look at the investment landscape of AI, you can see that there is a lot of push from a number of strong players and private investors. And they don't bear the costs when it comes to pollution, water bankruptcy, land degradation and so on.

If you think about the emissions, they are contributing to global warming, and everybody would suffer from it. Even the countries that don't have AI infrastructure are affected: If you think about where the critical minerals come from, you see a lot of poor communities, poor countries and poor regions in Africa, South America, parts of Asia, where people don't have basic infrastructure — they don't even have clean drinking water and energy infrastructure. They don't benefit from this expansion and the profits and utilities it provides. It's the most vulnerable communities and the poor economies that are going to suffer the consequences, while the other ones will benefit more.

SP: How did you estimate AI's growth by 2030, and how likely is it that your numbers will come true, given the fears that AI is a bubble that's about to catastrophically burst?

KM: We were looking at the data centers, and we still think that our projections are conservative. There is a lot of push from the private sector to further growth. Countries are also seeing investment in AI and data centers as an investment in security, sovereignty and other matters, so there's also a competition there. Some of the investments — some of the decisions about expanding AI — are not necessarily based on comprehensive assessments. Investments remain a bid to stay in the race, and that means more and more push. So we think that what we have projected is probably very conservative.

SP: China is scaling up its energy capacity together with data center buildout, and it is putting data centers in the ocean to try to solve the hardware cooling issue. What do you make of this strategy, and should other countries learn from it?

KM: China's more centralized decision-making system provides advantages, but I think we need to be careful about generalizing the information of one or two projects highlighted by the media to the overall strategy.

We know that China has been expanding its renewable energy production capacity, and that's definitely a good thing. We have to make sure that the additional load of AI would not mean more fossil energy and would not compromise the decarbonization process. But at the same time, we should note that just scaling up renewables is not sufficient if you're thinking about decarbonization. We need a massive addition of renewables if we're going to reverse climate change, and we are not seeing strong enough signs of that around the world. So that's something that we have to be worried about.

That has been the challenge created for the world because of the expansion of AI. When it comes to putting things under the ocean, I think we do not yet have enough information and enough experience to judge if those things come with less environmental impact. What we hide would not be impact-free; there are also other impacts to worry about.

SP: What are some other solutions to the pressures AI is putting on the environment and people? How should we approach the rapid expansion to ensure it is fair?

KM: We offer a framework based on a number of principles about making the AI governance system more fair and transparent and sustainable. So, those are the principles suggested, and they bring responsibility to all stakeholders, including the developers and service providers — those who provide the technology and have responsibilities of ensuring that their systems are more transparent and efficient.

Then, we have the governments that have the responsibility of ensuring that information becomes available, that footprints are properly monitored and disclosed and regulated. They can use a range of incentives, mechanisms or penalties to ensure that footprints are reduced across the supply chain — and I insist on that — from the mines to the landfill. So, that can be done; pollution taxes can be charged and so on. [Governments should ensure] that those who have to deal with the consequences also benefit from the profits and the opportunities that data centers bring to their communities. Decisions must be made based on resource availability and the environmental consequences taken into account.

Users also can do a better job of making smarter choices by using AI more responsibly and only when it's absolutely necessary. When using AI, choose the right models, and be mindful of what is happening behind the scenes. Is it really necessary to generate another image? Is it really necessary to generate a video? Is it necessary to use the model in the "thinking mode"? Together, all the stakeholders can make a difference, and users can also call for more transparency and force governments to take action to force the service providers to provide more information and be more transparent.

Editor's note: This interview has been condensed and lightly edited for clarity.

Rainforests are some of the most important and diverse ecosystems on Earth. Found across several continents, these vast forests are home to millions of plants and animal species, many of which can't be found anywhere else. Many rainforests, both tropical and temperate, also play a crucial role in regulating the planet's climate by absorbing carbon dioxide and producing oxygen.

Rainforests vary immensely in size. Some stretch across multiple countries and cover millions of square miles, while others are much smaller but still support incredible biodiversity. Understanding the relative size of these rainforests helps us appreciate their role on our planet and the challenges involved in preserving them.

In this quiz, you'll test your knowledge by sorting the top 10 biggest rainforests from largest to smallest. Click on and drag the blue rectangles to place them in the right order. Remember to log in to put your name on the leaderboard; hints are available if you click the yellow button.

Related quizzes:

Earth quiz: What do you know about our planet's most amazing features?

Yellowstone quiz: How much do you know about the first national park?

Equator quiz: Can you name the 13 countries that sit on Earth's central line?

Evidence of two ancient wooden posts aligned with the summer and winter solstices has been discovered near Stonehenge in southwest England. The posts have rotted away, and only traces of the postholes survive. But archaeologists say the structure predated Stonehenge, and they think it was a temporary religious monument until a permanent one was built. They even suggest it may have been a Stonehenge prototype.

Analysis suggests that ancient people used the posts to mark the summer and winter solstices, Phil Harding, an archaeologist at Wessex Archaeology who's leading the project, noted at a news conference on Wednesday (June 17).

"These people were capable of establishing the points on the horizon where the sun rises in the midsummer and sets in midwinter," he said. "This was a pioneering achievement." (The 2026 summer solstice will be celebrated at Stonehenge on June 21.)

Harding's team at Wessex Archaeology, a private firm that often works for the government and local authorities, publicly announced the finds June 18 in the U.K., and a report on their research will be peer-reviewed and published. The ancient monument consisted of the two large, wooden posts, about 400 feet (120 meters) apart, on land near the village of Bulford, a few miles east of Stonehenge.

The land is now controlled by the U.K. Ministry of Defence, but archaeologists have been allowed to excavate there since 2015. They previously found traces of two "henges" ‪—‬ rings of ditches and banks made from earth ‪—‬ and dozens of Neolithic pits from about 5,000 years ago, centuries before Stonehenge was completed. The pits were filled with animal bones, pottery, flints and charcoal, and the researchers think they date to the time that the first phase of Stonehenge was being built.

Solstice alignment

The posts were aligned to point along an axis that marked the direction of sunrise on the summer solstice, or "midsummer's day," and the setting of the sun exactly six months later, at the winter solstice, or "midwinter's day," according to a statement from Wessex Archaeology. The same astronomical alignments are seen at Stonehenge.

The animal bones and other signs of feasting in the pits at Bulford are evidence of large numbers of people gathering for religious festivals. (Signs of ancient feasting have also been found at Stonehenge.)

"When we talk about the solstice, we're talking about religion," Matt Leivers, an archaeologist at Wessex Archaeology and one of the researchers, said in the statement. "What we see at Bulford, and later at Stonehenge, is a way of celebrating and marking the passage of time, but it's also about making sure the world keeps working as it should."

The site predates the largest circles of stones at Stonehenge, which have the same alignments. "What we've discovered at Bulford is 500 years earlier than the famous stones we know so well," Harding said. The researchers even suggest that the Bulford monument may have been a sort of prototype for Stonehenge itself.

Ancient stones

Stonehenge is the world's most famous Neolithic monument, but its original purpose was long a mystery. Archaeological investigations have established that the first earthwork henge was started there about 5,000 years ago, and the famous central stones were added about 500 years later.

Recent discoveries at Stonehenge include evidence of ancient cremations, and many archaeologists now think the monument was originally a burial site. If that's the case, the alignment with sunset on the winter solstice might have represented "new life," as the days then became longer and warmer after the depths of winter. However, no human remains have been found at the Bulford site.

Susan Greaney, an archaeologist at the University of Exeter who was not involved in the research, said the new finds show the importance of the region to prehistoric people. "It is intriguing to think that simple posts were erected here to align with the solstices around 500 years before Stonehenge was built," she told Live Science.

The Bulford monument may have been a temporary "model" for Stonehenge itself, Amanda Chadburn, an independent archaeologist who wasn't involved in the research, told Live Science "If you were designing a very complicated piece of engineering like Stonehenge," she said, "you would have had to understand how to make it before starting."

See how much you know about Stonehenge with our Stonehenge quiz!

Archaeologists have discovered an iron cannonball fired by Texans at the Battle of the Alamo in 1836. This is the second intact cannonball they have discovered from the famous conflict. The first one, a bronze cannonball, was found earlier this year and was likely fired by the Mexican army.

"It's a huge deal," Tiffany Lindley, director of archaeology at the Alamo, said in a video statement from Alamo Trust. "We all thought, 'There's no way we can top it,'" she said, referring to the bronze cannonball discovered March 5, just a day before the 190th anniversary of the conflict that killed Davy Crockett, "and then we found another one."

Both cannonballs were recovered from the northeast corner of the church at the Alamo, which was originally built in 1718 as a Spanish mission and fortress in what is now San Antonio. But the Alamo is better known as the location of an 1836 battle during the Texas Revolution, in which Anglo-American settlers and Hispanic Texans known as Tejanos seceded from the Republic of Mexico.

In a 13-day siege culminating in a deadly assault on March 6, 1836, Mexican troops, commanded by Gen. Antonio López de Santa Anna, surrounded the Alamo and killed the 180 Texan rebels defending the structure, including Davy Crockett. The cry "Remember the Alamo!" was used in later skirmishes in the Texas Revolution as soldiers fought Mexican troops for independence.

The newly excavated iron cannonball was found June 2, according to a statement from Alamo Trust.

Of the two cannonballs, "the newest one is slightly larger" and was likely fired from a cannon that shot 6-pound [2.7 kilogram] cannonballs, Kolby Lanham, a senior researcher and historian at the Alamo, said in the statement. "The likelihood is that the bronze one belonged to the Mexican Army and the iron one belonged to the Texans."

Over the years, archaeologists have found numerous pieces of ammunition and shrapnel at the Alamo, Lindley said, but these cannonballs are the first examples of solid shots — spherical projectiles fired from a gun or cannon — they have ever found.

"It's just a huge kind of once-in-a-lifetime deal," Lanham said. "But obviously, it's happened twice."

The Mexican and Texan cannonballs were found near each other, so they are likely the historic remains of the two sides shooting at each other in the fateful siege nearly two centuries ago.

"Whenever they were dropped the very first time — possibly in 1836, probably — they haven't been touched since, and that's what makes them extra special," Lindley said. "I don't think you can undersell it."

The Alamo remains an active archaeological site, where experts have discovered artifacts that span its centuries of history, from Indigenous stone tools that predate the Spanish mission through the late 19th century, when the structure was converted into a general store and warehouse.

Can you identify these historical objects of war? Test your smarts with our weapons of the world quiz!

Physicists recently wondered what would happen if you tried to split a photon ‪—‬ and they found some unexpected behavior that may transform the way we think about particles.

The experiment, in which researchers simulated a photon being sliced by a shutter under various conditions, showed that a severed photon can lead to a complex mixture of zero to infinitely-many photons — raising some big questions about the nature of particle interactions.

Photons are elementary packets of light, which means they are not made up of anything else. So what does it even mean to try splitting a photon? It may be possible thanks to wave-particle duality — a core principle of quantum mechanics, the bizarre physics of the very small.

According to wave-particle duality, a photon is not only a particle but also a wave. Using theoretical calculations, the researchers investigated what would happen if you sent this photon through a shutter and closed it while the photon was passing through, effectively cutting off the tail end of the photon wave.

"I think that most physicists would expect there to be a certain probability that you have zero photons and a certain probability that you have a single photon left after you have done this," Johannes Skaar, co-author of the new study and a professor of theoretical physics at the University of Oslo, told Live Science. "And that is approximately true, but it is not exactly true."

What are the chances?

This brings up another strange aspect of quantum mechanics: its probabilistic nature. Particles exist as a cloud of probabilities stretching to infinity. Until a particle is observed, its properties, such as its position or energy, are in a superposition of possible values; all we can know are the chances of finding it in a certain state.

Through their calculations, Skaar and his colleagues determined how cutting a photon affects these probabilities. In their study, recently accepted in the journal Physical Review Letters, they found that it would create a complex mixture of photon states, including one with an infinite number of photons.

Each of these states has a probability that depends on how quickly the shutter cuts the photon. The expected number of photons becomes infinite only if the shutter is closed infinitely quickly. For realistic shutter speeds, even a thousand photons would be extremely unlikely.

This may sound very strange, but the quantum physicists were unfazed. In fact, what surprised Skaar and his colleagues was what happens if you make measurements of the cut photon from different perspectives.

"When you measure from one side of the shutter, then it will look like a single photon state," Skaar said. "Then, on the other side, it will look like a vacuum state — that means no photons. And that is very strange because the actual state globally is this mixture from zero to infinity."

Changing how we think about particles

The fact that these complex mixtures can be treated locally as very simple states raises fundamental questions about the nature of particles. Skaar said they are still reckoning with the full extent of these implications and they are now considering how this process could play out for other quantum particles, such as electrons.

They hope that by following this theoretical thread through, they may be able to develop a neater way of describing particle interactions. Currently, particles' infinite stretching means they have been interacting for an infinite amount of time. This then poses a problem for causality ‪—‬ the order of cause and effect ‪—‬ in particle interactions, the team said.

These new theoretical photons with a cutoff tail would not have this problem, meaning the causal link in an interaction would be clear, Skaar said. He admitted that there is much more work to be done to develop the theoretical description of this interaction. However, the new result is an important step toward describing particle interactions with a clear causal relationship, which Skaar described as the team's "ultimate goal."

Hunter-gatherers in Siberia fell victim to lethal plague outbreaks around 5,500 years ago, marking the oldest known evidence of plague to date, a new study finds.

A research team investigating the Stone Age remains identified ancient DNA ion over a dozen individuals that came from previously unknown strains of Yersinia pestis, a bacterium that causes pneumonic, bubonic and septicemic plague.

The disease that infected these hunter-gatherers, most likely pneumonic plague, probably spilled over from wild marmots, and ravaged through family groups living around Lake Baikal, according to the study, published Wednesday (June 17) in the journal Nature.

Ancient DNA from the two newfound plague strains revealed a unique gene that codes for proteins that trigger massive immune responses, perhaps explaining why children were the most likely to die from the disease, the authors wrote in the study.

The discovery of two deadly plague outbreaks in prehistoric hunter-gatherers challenges the long-standing assumption that epidemics first occurred after the rise of agriculture, study first author Ruairidh Macleod, a researcher of ancient genomics at the University of Oxford, told Live Science.

"We got the really striking result that we found lots and lots of plague here far earlier than we expected," Macleod said. This is "the closest we'll probably ever get to a direct smoking gun demonstrating the virulence [the ability of germs to cause disease] of these early plagues."

Plague has played an extremely important part in human history and continues to infect people today. The strain of Y. pestis that affects people today still causes epidemics, predominantly in Africa, although seven human cases, on average, are reported in the U.S. each year. Nowadays, Y. pestis cases that are caught early can be treated with antibiotics.

Understanding how the disease has evolved over time is essential for gaining insight into how Y. pestis may change in the future, study co-author Eske Willerslev, an evolutionary geneticist at the University of Copenhagen, said at a news conference Tuesday (June 16), ahead of the study's publication.

Prehistoric plague outbreaks

Research suggests that plague outbreaks devastated communities long before the Black Death, the catastrophic epidemic that swept through 14th-century Europe and killed around 25 million people, or between 25% and 33% of Western Europe's population at the time.

For example, repeated plague outbreaks have been identified from between 5,300 and 4,900 years ago in farmers from what is now Scandinavia. However, whether these early plague strains were deadly or simply caused mild sickness has been hotly debated because the bacterium lacked some known disease-causing genes.

Now, a close inspection of the ancient DNA of hunter-gatherers buried in four cemeteries along the banks of the Angara River, which flows out of Lake Baikal, has provided "the best kind of evidence that we could probably hope for" that prehistoric plague strains were lethal and resulted in mass death, Macleod said.

During previous excavations of these cemeteries, researchers noticed that an unusually high number of children had been buried over a short period. There were no signs of violence or other injuries, Macleod said at the news conference, leaving the archaeologists stumped as to why so many children died.

Macleod and his team stepped in to see if ancient DNA could shed light on this mystery.

The researchers extracted ancient DNA from the teeth of 46 individuals at the four cemeteries. They checked whether any were related while also scanning for ancient DNA from known germs.

To their surprise, they identified large amounts of Y. pestis in 18 individuals. These cases spanned two distinct disease outbreaks: one lasting from around 5,596 to 5,341 years ago, and another most likely spanning 5,126 to 4,926 years ago.

Some graves contained the remains of multiple infected individuals who were buried at the same time, suggesting they died during the same outbreak. One grave belonged to three closely related young girls, while another held a nephew and aunt.

"There must have been survivors who knew these people when they were alive and what their identities were and what their biological relationships were to bury the dead and bury them in shared graves," Macleod said.

It is currently not possible to identify plague-specific antibodies that would identify which individuals survived the outbreaks, he added.

The findings help to support the idea that prehistoric populations were impacted by plague, Aida Andrades Valtueña, a researcher who specializes in ancient pathogens at the Max Planck Institute for Evolutionary Anthropology in Germany but was not involved in the study, told Live Science in an email.

However, more complete sequencing of the plague DNA is needed to confirm that the various cases were from the same outbreak, rather than from separate infections, she noted.

What do you know about the Paleolithic, Mesolithic and Neolithic eras? Find out with our Stone Age quiz.

A Chinese spacecraft has arrived at one of Earth's temporary "quasi-moons" and will soon attempt to land on the space rock to scoop up samples that will be returned to our planet next year. The ambitious mission could help researchers uncover secrets about Earth's main moon and provide clues that may benefit space exploration and planetary defense, experts say.

The Chinese National Space Agency (CNSA) probe, named Tianwen-2, launched from Xichang Satellite Launch Center in southern China on May 28, 2025, Live Science's sister site Space.com reported at the time. The car-sized spacecraft sent back its first images a few weeks later, giving us our first glimpse of its secretive design, followed by a selfie with Earth a few months later.

The mission's primary target is 469219 Kamo'oalewa — also known as 2016 HO3 or simply Kamo'oalewa — a near-Earth asteroid discovered in 2016 by astronomers at Hawaii's Haleakala Observatory. It likely spans somewhere between 130 and 330 feet (40 to 100 meters) across and is a "quasi-satellite" of our planet, meaning it's orbiting the sun right alongside Earth in a temporary partnership. (Kamo'oalewa means "oscillating celestial fragment" in Hawaiian.)

Tianwen-2 is predicted to have arrived at Kamo'oalewa on June 7 and inserted itself into an orbit alongside the asteroid, according to an unverified timeline shared by freelance journalist Andrew Jones, a leading expert on China's space program. Around a month later, on July 4, the probe is expected to descend upon the space rock to collect samples from its surface, potentially employing a never-before-seen drilling technique to do so. (The CNSA has not released an official timeline for the mission or shared any recent updates about its progress.)

If successful, the samples are expected to be returned to Earth on Nov. 29, 2027, according to the same timeline. At this point, Tianwen-2 will then slingshot around our planet and head farther out into the solar system for its secondary mission: to rendezvous with and study 311P/PanSTARRS — a peculiar object beyond Mars, which displays characteristics of both comets and asteroids — in 2035.

Samples from Kamo'oalewa could help answer many interesting questions, including the true origin of the object, which some experts believe may have broken off from the moon.

"What makes [this mission] extraordinary is that we don't yet know [the object's] composition or origin," Li Chunlai, a researcher with the Chinese Academy of Sciences' National Astronomical Observatories and chief commander of Tianwen-2's ground application system, said in a state-sanctioned video translated to English. "We'll only obtain definitive answers after completing our exploration."

What is Kamo'oalewa?

There are currently eight known quasi-moons orbiting the sun alongside Earth, following the most recent quasi-moon discovery in September 2025. Unlike the similarly named "minimoons," which are asteroids that are briefly captured by Earth's gravity for a few months or years at a time, quasi-moons are temporary satellites that slowly circle our planet but are never gravitationally bound to it.

This relationship can last decades, or even centuries. For example, experts think Kamo'oalewa has been accompanying our planet for at least 100 years and could remain alongside it for another 300 years before it starts to fall out of sync with our solar orbit.

"The way Kamo'oalewa moves with Earth is kind of like a dog that might tag along with you for a while on a long walk through the woods, but it's not your dog," Richard Binzel, a planetary scientist and asteroid expert at MIT, told Live Science in an email.

The Ferris-wheel-size space rock is one of the closest quasi-moons to us, with a minimum distance of around 2.9 million miles (4.6 million kilometers) from Earth, or around 12 times farther away than our actual moon. It is also one of the fastest-spinning quasi-moons, rotating around its axis every 30 minutes. But unlike other quasi-moons, which likely originate from the solar system's main asteroid belt, between Mars and Jupiter, our current best guess is that Kamo'oalewa is actually a piece of the moon.

This hypothesis is based on observations from 2021 that showed Kamo'oalewa absorbs and reflects light similarly to the moon, hinting that the space rock may be a chunk of lunar material ejected by a long-ago meteor strike. More recently, in 2024, researchers narrowed down the most likely impact crater from which the asteroid originated: the 13.6-mile-wide (22 km) Giordano Bruno crater, located on the far side of the moon. However, there is still a chance that Kamo'oalewa is a main-belt asteroid that just happens to look an awful lot like lunar material.

"I am curious to find out the answer about its origin, since the debate on its [potential] lunar origin is still very open," Marco Fenucci, a mathematician at the European Space Agency's Near-Earth Objects Coordination Centre who has co-authored multiple studies on Kamo'oalewa, told Live Science. This mission should "definitely give us an answer to this matter," he added.

Scientists are also unsure whether Kamo'oalewa is a "solid monolithic rock," like the $100,000 quadrillion asteroid Psyche (the target of NASA's ongoing Psyche mission), or a "rubble-pile-like asteroid," such as Bennu or Ryugu, both of which have been explored by sample-return missions in recent years, Fenucci said.

Scooping up samples

Having arrived at Kamo'oalewa, Tianwen-2 will spend the next few weeks mapping the asteroid's surface at altitudes between 1,000 feet and 12.5 miles (300 m to 20 km) above its surface, according to limited mission details revealed by Chinese scientists in a January study. The resulting map will allow researchers to estimate the asteroid's density and work out the best landing spot.

On July 4, the probe is expected to swoop down and scoop up around 3.5 ounces (100 grams) of surface material, or regolith, from the asteroid, which is slightly less than what NASA's OSIRIS-REx mission managed to grab from Bennu. However, there are multiple ways this sampling process could play out.

If the asteroid is a pile of rubble, the probe will utilize a touch-and-go approach, which involves hovering just above the surface and using a robotic arm to reach out and grab the sample. This method was also used by OSIRIS-REx for Bennu and by Japan's Hayabusa2 mission, which scooped up samples from Ryugu.

But if Kamo'oalewa has a more solid surface, Tianwen-2 will attempt to land directly on the space rock and anchor itself in place before drilling into the asteroid. This has never been attempted before and could allow for longer contact time and "more controlled sampling," according to The Planetary Society.

After collecting samples, the probe will remain alongside the asteroid and conduct further analysis of its size, shape and trajectory.

In late April 2027, Tianwen-2 will depart Kamo'oalewa and begin the six-month journey back to Earth, where it will dump its samples in a return capsule that will fall to our planet's surface as the probe begins its long journey to rendezvous with 311P/PanSTARRS.

The return capsule will reenter Earth's atmosphere at around 27,000 mph (43,500 km/h), researchers wrote in the January study. That's slightly faster than the Orion capsule carrying the Artemis II astronauts traveled as it fell back to Earth in April.

What could we learn from Tianwen-2?

In addition to ending the debate over Kamo'oalewa's origin, samples from Tianwen-2 could reveal more about the solar system and our place within it.

For example, previously returned asteroid samples have helped to "tell us where Earth's water came from, how complex organic molecules were distributed in the early solar system, and how surface processes like space weathering alter asteroid properties over time," Fenucci said. These samples can also be used to "establish a link to known meteorites found on Earth" and help us learn more about these space rocks, he added.

The proximity of quasi-moons and minimoons to Earth also makes them valuable assets for future space exploration missions. Some researchers have proposed using them as temporary bases or refueling stations that could serve as stops on the way to Mars or other faraway destinations. These objects "could become literal stepping stones for human missions to practice what it is like to leave the Earth-moon cradle," Binzel said.

One particular idea that scientists want to explore is whether water can be extracted from these objects. And if Kamo'oalewa is a piece of the moon, that could have implications for NASA's planned moon base. "Someday, it might be possible to extract that water to provide resources for thirsty astronauts or even generate usable rocket fuel from the hydrogen," Binzel said.

Some near-Earth objects also pose a potential risk to our planet. And while Kamo'oalewa will likely never hit us (and would probably only cause localized damage if it did), there are much larger nearby space rocks that could trigger global catastrophes if they were to impact our planet.

"Over the time scale of centuries, these kinds of objects have a chance of striking the Earth," said Binzel, who invented the Torino scale used to measure the impact potential of near-Earth objects. Therefore, a better understanding of space rocks like Kamo'oalewa "can prepare us in how to deal with a threatening object if one were ever discovered," he added.

Finally, this mission will likely provide another opportunity to assess China's space exploration capabilities, which could hint at whether the country could overtake the U.S. as the top nation in space, as some experts predict.

A giant blob of abnormally cold water in the North Atlantic Ocean is shifting the Indian summer monsoon, threatening the livelihoods of more than 1 billion people, new research suggests.

The link between these two systems highlights a previously unrecognized connection that could inform weather forecasts in South Asia and shed light on climatic events elsewhere, scientists say.

The Indian summer monsoon is a rainfall pattern that lasts from June to September and is driven by temperature differences between the warm northern Indian Ocean and cooler seawater below the equator. Historically, the monsoon triggered heavy rainfall along the west coast of India and a huge region of northern India called the Indo-Gangetic Plain. But since 1999, this pattern has changed dramatically, the researchers reported in a new study.

Northwest India now receives about 25% more rain during the monsoon season than it did before 1999, while the Indo-Gangetic Plain gets roughly 4% less, the team found. This is disastrous for farmers, in particular, because their soils and crops are adapted to the old rainfall pattern, said study first author Mahendra Nimmakanti, a climate scientist at the Indian Institute of Science's Centre for Atmospheric and Oceanic Sciences.

"India is largely dependent on agriculture," Nimmakanti told Live Science in a joint interview with study co-author Matthew Huber, a professor in the Department of Earth, Atmospheric, and Planetary Sciences at Purdue University in Indiana. Higher-than-normal precipitation in northwest India is causing flash floods and crop losses, because agriculture in this region is adapted to dry conditions. Meanwhile, the Indo-Gangetic Plain has seen periods of drought that also caused crop declines and impacted farmers' livelihoods, Nimmakanti said.

Previous studies have linked shifts in the Indian summer monsoon to changes in the Atlantic Meridional Overturning Circulation (AMOC), a giant web of ocean currents in the Atlantic that regulates the global climate and carries heat to the Northern Hemisphere. Data suggests the AMOC is slowing due to climate change and releasing less heat in the North Atlantic Ocean than it did before. This may be causing a southward shift of the Intertropical Convergence Zone, a band of low-pressure atmospheric conditions around the equator that drives tropical monsoons, including the Indian summer monsoon.

But these studies didn't specify how the Indian monsoon might shift or explain the underlying mechanism in detail, Nimmakanti said. "They generally explain that if there is a weakening of AMOC, that suppresses the Indian summer monsoon," he said.

One part of the problem is that current climate models do not show the changes in the Indian monsoon that have happened in real life, possibly because they also don't fully capture shifts in North Atlantic sea surface temperatures. This is especially true for a region southeast of Greenland known as the "cold blob," where the water was colder between 1901 and 2021 than it was in the late 1800s, even as the ocean around it heated up.

The cold blob suggests the AMOC is weakening because it points to a reduction in the amount of heat reaching the North Atlantic.

To pinpoint how and why the Indian monsoon has changed, the researchers fed precipitation data, sea surface temperature records and other real-life observations into dozens of climate models. This reproduced the shifts observed over the past 27 years. However, the results only implied a correlation between shifts in the North Atlantic and changes in the monsoon, not that the former directly caused the latter.

To figure out if North Atlantic sea surface temperatures caused the Indian monsoon to behave strangely, the team added and removed the cold blob in a simulation. The results showed that the cold blob has shifted the Indian monsoon by creating a strong temperature gradient over the North Atlantic, which, in turn, affects jet stream winds and pressure systems in the atmosphere above Eurasia.

Specifically, the jet stream above the North Atlantic has intensified, and a "blocking" system over the Ural Mountains in western Russia has strengthened, Huber said. As a result, weather systems in India have changed, sucking moist air toward the country's northwest and away from other regions.

"It's a shifting of the high- and low-pressure systems," Huber said. "Realizing that these two systems were directly linked through this wave train coming off the North Atlantic, that was novel."

More than 1 billion people in India and other parts of South Asia depend on the monsoon for food security and economic stability. The new results, published April 27 in the journal AGU Advances, could help forecasters predict extreme rainfall and drought events in India and neighboring countries like Pakistan during the monsoon season.

Some researchers think the Indian monsoon is a key tipping point within the global climate, and the findings suggest the system crossed a threshold in 1999. Since then, the cold blob has caused a "persistent jet stream reorganization," leading to abrupt shifts in the monsoon, according to the study.

It's unclear how the Indian monsoon will evolve under intensifying climate change, because climate models produce different predictions of what will happen in the North Atlantic, and other drivers may come into play as the world changes, Huber said.

"What we do now know is that this is one of the key building blocks of formulating a theory for what will happen in the future," he said.

Corvids, including ravens and crows, have earned a reputation for being some of the smartest birds on Earth. They can recognize human faces, use tools, solve multistep puzzles and even hold funerals.

In recent years, scientists have added another surprising skill to the list: a grasp of numbers. Research suggests that corvids can distinguish between different quantities and, in some cases, even perform statistical analysis.

These discoveries have raised a provocative question: How deep do the roots of mathematical thinking go? While modern humans are the only known species to develop formal mathematics, studies of crows, monkeys and other animals suggest that the cognitive building blocks of math may have evolved hundreds of millions of years before people began doing calculations.

Few researchers have done more to uncover these abilities than Andreas Nieder, a professor of animal physiology and the director of the Institute of Neurobiology at the University of Tübingen in Germany. By examining the neural activity of both monkeys and crows, Nieder has found evidence that very different animal brains can process numerical information in surprisingly similar ways. Live Science spoke with Nieder about how these findings may reveal that the origins of mathematics are far older than our species.

Kenna Hughes-Castleberry: How did you get into researching crows and primates?

Andreas Nieder: After studying the auditory and visual systems for several years as a student, I realized that I wanted to focus on the neuronal foundations of intelligence and cognitive control functions. How does the brain give rise to abstract concepts, working memory, or the ability to follow complex rules deliberately? Of course, to study intelligence, you need intelligence specialists. I therefore began working with primates ‪—‬ more specifically, rhesus monkeys, arguably among the most intelligent mammals. They are closely related to humans, possess relatively similar brains, and share many cognitive abilities with us.

However, as a trained biologist, I was always interested in a broader evolutionary question: Are sophisticated cognitive abilities unique to mammals, or can they emerge in very different brains? Crows provided an ideal comparative species. Birds diverged from mammals more than 360 million years ago — roughly six times longer ago than the extinction of the dinosaurs. Yet despite this immense evolutionary distance, corvids display remarkably flexible behavior; in many ways, they are the feathered primates of the air.

KHC: Are crows difficult to study? Are they fun? Do they have personalities?

AN: Both primates and crows are demanding to study. Because they are highly intelligent, they require special housing and care. Since we investigate cognitive abilities under tightly controlled experimental conditions, they also require extensive behavioral training by skilled personnel. And, of course, the regulations governing research with these species are particularly strict.

At the same time, they are fascinating research subjects. Individual monkeys and crows differ noticeably in temperament and behavior. Some are curious and adventurous, others are cautious and reserved, and some learn new tasks much faster than others.

Their qualities can be quite striking. Some are reliable, highly motivated workers that perform consistently day after day. Others are sensitive divas who seem to require special treatment before they are willing to cooperate. Researchers generally avoid anthropomorphizing, but there is little doubt that individual animals exhibit stable behavioral traits that we would reasonably describe as distinct characters.

KHC: You've found that crows understand the concept of zero. How do we know this?

AN: We trained crows to recognize different numbers — sets containing one, two, three, four objects, and so forth. We then included trials in which no items appeared at all. The remarkable finding was that the birds treated an empty set as a quantity and as part of the numerical continuum. They behaved as though the empty set belonged before "one." Their error patterns were particularly revealing: They confused zero more often with one than with larger numbers, exactly as one would expect if zero were mentally represented as a numerical quantity next to one. In addition, recordings from neurons in the crow brain showed cells that responded selectively to empty sets. This suggests that zero is not merely a behavioral trick but is represented neurally as a meaningful numerical category.

KHC: To play devil's advocate, is the ability to recognize the difference between something and the lack of something really that surprising? Is it akin to the human concept of zero?

AN: That's an important question. Simply recognizing that nothing is present or absent is not surprising. Many animals can distinguish between the presence and absence of objects. The key issue is whether they treat "nothing" as a quantity that can be compared to other quantities.

Our experiments suggest that crows do more than detect absence. They position empty sets within an ordered numerical sequence, at the low end of the number line, and show distance effects similar to those observed with other numbers. For example, they find it easier to distinguish zero from two than zero from one.

That said, we should not claim that crows possess the full human mathematical concept of zero. Humans use symbolic zero in arithmetic, algebra, calculus and formal mathematics. What we have demonstrated is a foundational precursor: a nonsymbolic numerical representation of zero. This may represent an evolutionary building block from which more sophisticated human concepts eventually developed.

KHC: You've also found that crows can perform statistical analysis. Tell me more about these findings and what you showed.

AN: We trained carrion crows [Corvus corone] to associate a series of arbitrary visual signs, colored geometric images displayed on a touch screen, with different reward probabilities. One sign might yield a food reward 90% of the time, another 70%, another 50%, and so on down to 10%. Importantly, the signs themselves carried no inherent meaning; the birds had to learn these probabilities through experience.

Once the birds had learned these sign-probability associations, we presented them with pairs of signs and asked them to choose one. To maximize their rewards, they should select the sign associated with the higher reward probability. The crows did exactly that. Even when confronted with many novel pairings, they reliably chose the statistically more favorable option.

This does not mean that crows perform formal statistics in the human sense. They are not calculating percentages or solving probability equations. However, the results show that they can extract probabilistic regularities from experience, store this information in memory, and use it flexibly to make reward-maximizing decisions under uncertainty. These are fundamental ingredients of statistical reasoning and are highly valuable in natural environments, where animals constantly have to make decisions based on incomplete information.

KHC: Have researchers tried similar tests on babies or young humans, and if so, how do we stack up?

AN: Yes. Developmental psychologists have conducted many related studies with infants and young children. Even before learning language, infants show sensitivity to quantities, numerical differences and simple probabilistic information. By around 4 years of age, children also display an intuitive understanding of empty sets.

What is striking is that the behavioral signatures observed in crows resemble those seen in preverbal human infants and nonhuman primates. Of course, human children eventually develop symbolic mathematics through language, education and culture, which takes them far beyond the abilities observed in animals.

KHC: Can these findings tell us anything about how the human understanding of math evolved?

AN: They suggest that some foundations of mathematics may predate humans by a very long evolutionary timescale. Humans did not invent numerical intuition from scratch. Rather, we appear to have inherited ancient cognitive systems that allow brains to estimate quantities, compare numbers, and represent concepts such as zero approximately.

The fact that crows and primates — two distantly related groups — show similar numerical abilities suggests that these capacities may emerge whenever evolution favors flexible intelligence. Human mathematics likely built upon these ancient cognitive foundations and then expanded dramatically through language, symbols and culture.

KHC: What's something a general audience might be surprised to learn about crows?

Many people are surprised to learn that crows are songbirds. Most people associate songbirds with melodic singers such as nightingales or blackbirds, not with the harsh cawing of a crow. Yet crows do learn a significant part of their vocal repertoire and are even known as apt imitators, even of human speech sounds — the internet is full of funny videos in which crows imitate human speech.

What makes this particularly interesting is that their vocalizations are not merely reflexive calls. In our experiments, we found that crows can exert volitional control over their vocal behavior. They can learn to produce vocalizations in response to arbitrary cues and withhold them when required, demonstrating a level of cognitive control over vocal output that is considered an important prerequisite for complex communication and, ultimately, language.

More recently, we showed that crows can even use their vocalizations to count. In a recent study published in [the journal] Science, we trained crows to produce a specific number of calls — between one and four — in response to visual or auditory cues. Remarkably, they not only generated the correct number of vocalizations but also appeared to prepare the intended number before they started calling. This suggests that they can represent numerical information and use it to guide a self-generated sequence of vocal actions.

Taken together, these findings show that crow vocalizations are far more sophisticated than most people assume. Their characteristic "caw" is not just a simple call — it can be brought under deliberate cognitive control and even used to express numerical information. For a bird, that is a remarkably advanced ability.

This interview has been edited for length and clarity.

Are you a bird nerd? Find out with our bird quiz!

In southwest China, Chinese soldiers load and fire rockets toward the sky as aircraft and drones circle overhead, dropping their toxic cargo into the air. The weapons are not trained on an enemy, and the planes aren't dropping bombs. Instead, they are targeting the clouds hovering in the sky.

This footage is just a tiny snapshot of the massive, countrywide effort to seed the clouds with rain at an unprecedented scale.

More than 50 countries around the world use cloud seeding to modify the weather at small scales, including the United States.

But China is the world leader, employing around 50,000 people; using thousands of rocket launchers and dozens of planes; and investing the equivalent of billions of dollars in these initiatives, experts told Live Science.

In 2018, China embarked on its most ambitious cloud seeding plan. The Tianhe ("Sky River") project aimed to create a permanent airborne water "corridor" from one river basin to another on the Tibetan Plateau. The project was intended to be part of the country's much bigger South-North Water Transfer project — a massive effort to transfer water to China's highly populated and water-scarce North and East.

From the start, the Sky River faced scathing criticism from scientists who said the project was unworkable. Yet China forged ahead.

China's pursuit of such a scientifically questionable geoengineering technology shows just how far Chinese authorities are prepared to go to achieve the country's water and climate goals. It also reveals how the Chinese government views the natural world, experts have said.

"There is an impetus to control and to view the environment as a machine or an infrastructure that can be controlled," Emily Yeh, a professor of geography at the University of Colorado Boulder, told Live Science.

The science of cloud seeding

China uses cloud seeding to produce precipitation to build up snowpack, help alleviate droughts, reduce the impact of hailstorms, and create skies clear of clouds and pollution for official events — as it did most famously during the 2008 Beijing Olympics, experts told Live science.

But cloud seeding can't create rain from an empty sky. Instead, it causes existing clouds to generate precipitation more efficiently by injecting particles into a cloud. Water droplets then coalesce around these particles, and the water eventually falls as rain or snow.

"Every single drop in any cloud you have ever seen — there's a particle in it," Rob Rauber, an atmospheric scientist at the University of Illinois Urbana-Champaign, told Live Science. Cloud seeding speeds up the raindrop-forming process by introducing more particles, he explained.

There are two main ways to do this, depending on whether the temperature of the clouds is above or below 32 degrees Fahrenheit (0 degrees Celsius). Warm-cloud seeding is known as hygroscopic seeding, while cold-cloud seeding is called glaciogenic seeding.

"They have the same general goals or approach," Jeff French, head of atmospheric science at the University of Wyoming, told Live Science. "And that is to introduce something into the cloud that would increase the efficiency in which cloud droplets or ice crystals are able to grow to precipitation-size particles and fall out of cloud either as rain or as snow."

A salt such as sodium chloride is typically used for hygroscopic seeding to attract water droplets, French said. Glaciogenic seeding, by contrast, takes advantage of cold clouds' supercooled water — water that is liquid even when temperatures are below freezing — by introducing silver iodide. This substance has a similar structure to ice and collides with supercooled water in a cloud, causing it to freeze and eventually fall from the cloud, French said.

Scientists insert seeding particles into clouds in a number of ways, including by dropping them from planes and drones, firing shells or rockets into the clouds from the ground, or burning materials in chambers that release the combustion byproducts into the air.

Scientists are still learning exactly when and how to use these techniques most effectively. Rauber and French both noted that it's difficult to quantify cloud seeding's impact.

"It becomes kind of a quagmire when you ask that question: 'Does cloud seeding work?'," French said. For his research, he used airplanes, ground sensors and radar across the U.S. Mountain West to measure the effects of seeding from aircraft on the initiation and growth of crystals and eventual snowfall. "From a physical standpoint, I can say very confidently that cloud seeding works," French said.

However, that experiment was in cold, mountainous conditions, and the impact of cloud seeding depends on many conditions, so tracking whether cloud seeding increases precipitation over a longer period and in different conditions can be challenging.

"Not all clouds are created equal," French said. Some are colder or warmer, and the seeding material won't work as well; in others, the size or distribution of droplets makes precipitation less likely. Even within a small region, the snowfall varies tremendously from one point to another. And beyond a small region, all bets are off.

"If you have a very successful cloud seeding program, that is producing, maybe 7% or 9% or even 10% more precipitation over a mountain range, downstream of that mountain range, the impact may be 1%," French said. "But it is a really difficult number to get our arms around."

French added that scientists should be careful to not overpromise what cloud seeding can accomplish.

"If the promise is that cloud seeding is going to eliminate droughts even on a local level, the answer is no, it can't live up to that. There's no scientific evidence," French said. But if targeted properly, it can moderately increase natural precipitation, he said.

Cloud seeding on the Tibetan Plateau

Despite cloud seeding's limitations, China has established weather modification bureaus across the country.

"They have a whole campus of people who are working in the weather modification field," Rauber said. "They have a fleet of aircraft — they're on a whole different scale than anything that goes on anywhere else in the world."

Chinese researchers claim that the country has made huge strides in its weather modification. Reports from state-owned media suggested that weather modification efforts increased precipitation by 168 billion tons between 2020 and 2025, and that in experiments, just one cup of cloud seeding material generated 30 Olympic-size pools' worth of precipitation over an area the size of Yellowstone National Park in the arid Xinjiang region.

These weather modifications have also been conducted on the Tibetan Plateau. The vitally important region, nicknamed Asia's Water Tower, is the source of multiple major rivers that supply water to nearly 2 billion people across Asia. But the plateau is facing increasing desertification and glacier loss due to human-caused climate change and other human activities such as overgrazing animals.

China's cloud-seeding ambitions for the plateau reached a whole new level in 2018, when authorities announced the Sky River project. The controversial project aimed to use cloud seeding to create precipitation across a 620,000-square-mile (1.6 million square kilometers) area in the Tibetan Plateau — about the size of Alaska — to divert Indian monsoon rains above the Yangtze River basin and channel the water to the Yellow River basin. From the Tibetan Plateau, the Yellow River flows north and east into the parched northern regions of China, while the Yangtze flows south and east into less-water-scarce areas. The initial plan claimed the project would transfer up to 7% of the country's total annual water consumption, reports noted.

The atmospheric channel was intended to be part of the country's colossal South-North Water Transfer Project, circumventing the region's challenging terrain by moving the water in the sky instead.

The plan, due to be completed in 2025, called for seeding this atmospheric river using tens of thousands of silver iodide-burning chambers on the ground, linked to a series of meteorological satellites that would analyze the weather conditions. Information from these satellites would automatically trigger the burners when the conditions were suitable for cloud seeding.

However, the plan was immediately met with a barrage of criticism from scientists in China. In a translated statement, Hancheng Lu, a professor at the National University of Defense Technology's School of Meteorology and Oceanography, called the project "an absurd and fantastical project with neither scientific basis nor technological feasibility."

The project was unworkable because it is not possible to convert all atmospheric moisture to rain, or to channel moisture in this way, Yeh said.

As of 2022, researchers were working on a significantly scaled-back version of the project. However, China's official channels have gone dark on the topic.

China's newly announced five-year plan, which sets out the policy direction of the country from 2026 to 2030, references weather modification enhancements but doesn't mention this specific project, according to reports from Chinese media.

This has led experts to speculate that the project was quietly canceled.

"When one goes to China and asks atmospheric scientists not involved in it about it, they just sort of laugh, and it's like this embarrassing incident," Yeh said. "It was never possible."

To see whether the project was still going forward, Live Science reached out to several researchers involved in the project, but they did not reply by the time of publication.

The fears of cloud seeding

The pursuit of the Sky River project — despite the low likelihood that it would ever work —— has caused significant alarm in neighboring countries. India relies on the monsoon rains and rivers such as the Brahmaputra, which starts in the Tibetan Plateau before flowing through India and Bangladesh on a 1,800-mile-long (2,900 km) route to the sea. There are also suspicions about cloud seeding being used to cause flooding across borders.

Many of these fears are overblown, experts told Live Science. Rauber noted that cloud seeding can't influence weather enough to reduce water in a wider weather system.

"This is always a question of, 'Are you robbing Peter to pay Paul?'" Rauber said. But the amount of water in storm clouds "is way greater than anything cloud seeding is going to extract."

Climate geoengineering

China's all-in pursuit of technologies like cloud seeding — even on the internationally important and politically sensitive Tibetan Plateau — has raised concerns that China is prepared to go to extreme lengths to engineer its way out of its problems — even when it involves scientifically dubious geoengineering projects with massive risks.

China's determination to address climate change and investment in megaprojects that attempt to engineer the natural world, such as the upcoming Motuo megadam in Tibet and colossal tree-planting projects in northern China, are also signs that China is moving toward larger climate geoengineering, experts have suggested.

This may even involve attempts to change how much sunlight reaches the planet's surface, experts have speculated.

"Given similarities, weather modification could serve as a means to incrementally build legitimacy for solar radiation management, in China and beyond, which may ultimately make it possible to deploy it," researchers argued in a 2019 study.

However, there's no evidence that China is currently pursuing such climate modifications, and it's unlikely they'd do so without some cooperation or buy-in from other countries, researchers wrote in 2023.

"It is currently unlikely that China would deploy SRM unilaterally. But its weather modification programme does demonstrate the country's willingness and capability to undertake large-scale atmospheric intervention projects," the study authors wrote.

Solar radiation modification aims to release particles such as sulfur high into the atmosphere to reflect sunlight back into space in an effort to limit global heating. It is being increasingly investigated by researchers and governments. The controversial concept has never been demonstrated on a large scale, and studies suggest it has many potential risks, such as the potential to shut down monsoon rains.

Scientists have already seen some of the negative impacts of natural solar radiation modification, for instance in the aftermath of large volcanic eruptions, such as Tambora in 1815. "It led to the suppression of the monsoon, because the monsoon is driven by heating from the sun, Rauber said. "And that cuts back on rain in tropical areas, and that causes droughts, which causes all sorts of diseases and can lead to mass starvation," he added.

"The evidence from nature is don't mess with Mother Nature," he said.

The patient: A 28-year-old woman in New Hampshire

The symptoms: In March 2020, the woman developed a high fever, chest tightness, shortness of breath and diarrhea, and she lost her sense of smell and taste. She also experienced coughing fits so intense that they caused her to faint. Based on these symptoms, her primary care provider diagnosed her with COVID-19, although she was not formally tested for the illness due to the lack of diagnostic testing available at the time.

After her diagnosis, she did not seek further medical care due to concerns about out-of-pocket costs, according to a report of the case.

What happened next: Three weeks after her symptoms started, the patient felt well enough to work from home. However, four weeks after that, many of her symptoms returned. She also noticed new feelings of disorientation and felt that "something was off with faces." Her primary care doctor suggested she go to an emergency room, where a CT scan was taken of her brain. The scan didn't show any active bleeding, the report notes, and she was discharged.

In June 2020, the patient spent time with family for the first time since catching COVID-19 and found she could not recognize her father or visually distinguish him from her uncle. She still recognized people by their voices, though.

The patient worked part time as a portrait artist; she used to be able to check her reference photos every 15 to 30 minutes but found she now struggled to hold the details in her mind. She told doctors that "faces are like water in my head," according to the case report.

The patient also had trouble doing everyday tasks, such as navigating her local grocery store or finding her way back to her car in a parking lot. In November 2020, she also started having balance issues and frequent migraines.

The diagnosis: Based on her wide-ranging and relapsing symptoms and her suspected history of COVID-19, doctors diagnosed the patient with post-acute sequelae of COVID-19 (PASC), now known as long COVID. They diagnosed her difficulties with recognizing faces as "face blindness," or prosopagnosia.

Roughly 2.5% of the general population is thought to be born with some degree of face blindness, while others can acquire the condition later in life. The exact number of people with acquired prosopagnosia is unclear, but some estimates suggest roughly 1 in 30,000 people in the U.S. are affected.

Many people with acquired prosopagnosia also have issues navigating familiar spaces. That was also the case with this patient, likely due to the "proximity of brain regions critical for scene and face processing," the case report authors noted.

To assess the extent of the patient's prosopagnosia, doctors had her complete several tests of facial memory, which asked her either to memorize strangers' faces or recognize celebrities' faces. The patient performed markedly worse on these tests than 10 women of similar age who were used as a comparison group.

However, she performed as well as the comparison group on other types of cognitive tests, suggesting her deficits were fairly specific to faces. She also got normal scores on tests of facial perception — the ability to recognize that a face is a face — so her face blindness seemed tied more to memory deficits for faces, the report authors said.

The treatment: The case report does not detail a specific course of treatment, and in general, few treatments exist for face blindness. If there's a clear cause for the deficit — such as a tumor in a key part of the brain for facial processing — addressing that underlying issue can help reverse acquired face blindness.

If the condition ends up being permanent, there are various strategies that can help patients cope. For instance, "perceptual training" can improve patients' ability to identify and remember the features of a person's face. Additional strategies include training people to use other cues, like voices and social context, to identify people.

What makes the case unique: In this patient's case, the report authors suspect that her COVID-19 infection triggered her face blindness either acutely or in the aftermath of the infection.

Various infections have been tied to face blindness; both bacterial meningitis and Whipple disease (caused by the bacterium Tropheryma whipplei) have been flagged as culprits, although such cases are uncommon. In a second known case involving COVID-19, a different person developed face blindness after an infection but had also had a stroke in the right hemisphere of their brain, a known cause of prosopagnosia.

The 28-year-old woman, by contrast, wasn't thought to have suffered a stroke, and it's unclear exactly how COVID-19 led to her facial processing issues.

The case report authors surveyed more than 50 other people with long COVID, to see if they also had signs of face blindness. While many showed general declines in visual recognition and navigational abilities, the group didn't have a specific problem with faces. So while long COVID is known to cause a range of neurological issues, it appears that face blindness is a rare consequence.

For more intriguing medical cases, check out our Diagnostic Dilemma archives.

This article is for informational purposes only and is not meant to offer medical advice.

Can you guess the diagnosis in these strange medical cases? Find out with our diagnostic dilemma quiz!

Archaeologists in Germany have unearthed an unusual burial of an injured man who was thrown into an abandoned kiln nearly 5,000 years ago. Because archaeologists don't typically find artifacts or bones in kiln pits, they suspect the man may have been a human sacrifice.

While workers were constructing a power line near Gerstewitz, a village in central Germany, archaeologists found a Corded Ware culture grave, according to a June 15 statement from the State Office for Heritage Management and Archaeology (LDA) Saxony-Anhalt.

The Corded Ware culture, named after the distinctive cord-like impressions found in their pottery, spread across Northern Europe between the Late Neolithic and the Bronze Age, around 2900 to 2050 B.C. Graves of Corded Ware people tend to follow a strict pattern: Men were buried on their right side, women were interred on their left, and everyone was buried in a crouched position facing south. But sometimes, graves deviate from this pattern.

The newly excavated grave at Gerstewitz revealed the skeleton of a man who was about 25 years old when he died. He was buried in a crouched position facing south, but rather than being placed in a grave or under a small mound, he was found in a kiln pit. This pit, essentially a hole that had been dug into the ground, held ancient evidence that people had used it to burn material, such as wood or food, or to fire clay. Additionally, the man's skull showed signs of injury.

Experts have suggested three possible explanations for the unusual burial. The skull injury may have resulted from violence, meaning someone murdered the man. Alternatively, he could have perished in a Copper Age battle lost to history. But a third possibility is that he was placed in a kiln pit as a human sacrifice.

Oliver Dietrich, an archaeologist at LDA Saxony-Anhalt, wrote in the statement that, in rare cases, Corded Ware kiln pits contain cow or dog bones thought to be sacrificial offerings to unknown deities. While it's possible this man was a human sacrifice, Dietrich noted that future laboratory analysis should provide more information about the grave and the person buried there.

This is not the first time a sacrificial pit has been found in Gerstewitz. Last year, archaeologists with LDA Saxony-Anhalt discovered 12 pits ringed by a moat-like ditch. The pits were full of dog bones, human skulls and complete ceramic pots and had been sealed with the rubble of burnt houses, according to a 2025 statement about that discovery. An additional human skeleton was found buried in a converted oven pit. These finds, however, were attributed to the Salzmünde Culture (3400 to 3050 B.C.), which predated the Corded Ware people.

Other discoveries near Gerstewitz have revealed that the area was settled and occupied for over 6,000 years. The excavation there will last until at least 2027, when the power line project is expected to be completed.

What do you know about the Paleolithic, Mesolithic and Neolithic eras? Find out with our Stone Age quiz!

Today (June 17), for the first time in 11 years, people across North America will be able to look up in the daytime sky and see Venus temporarily vanish behind the faint crescent moon.

The rare skywatching spectacle can be viewed with the naked eye and recorded without any special equipment, as long as the weather cooperates — however, using a good pair of binoculars or a backyard telescope will make it much easier to see the faint light of Venus in the daytime sky. No matter how you go about skywatching, you must take great care not to stare directly at the sun while doing so.

During the event, known as a lunar occultation, the moon will briefly pass between Earth and Venus, which has been shining especially bright over the past few weeks while hanging out alongside Jupiter in the evening sky. As a result of the occultation, the hellish planet will appear to blink out of existence, before reappearing around an hour later, allowing for two separate skywatching experiences. The last time this happened was on Dec. 7, 2015, and you will not be able to see it again until 2029.

How to see Venus disappear

The occultation will be visible from the 48 contiguous U.S. states, as well as from large parts of Canada and some countries in the northern half of South America — assuming there are clear skies at the time of the event. (The latest forecast suggests that weather conditions will be most favorable along the West Coast.)

As with most skywatching events, such as solar eclipses, not everyone will see it at the same time. For example, people in San Francisco will observe Venus vanish at around 11:34 a.m. PDT, while those in Miami will watch the planet disappear at about 4:06 p.m. EDT (around 92 minutes later when disregarding time zones).

The duration of the occultation will also vary with location. For example, Venus will reappear after around 58 minutes for viewers in San Antonio, but people in Philadelphia will have to wait roughly 80 minutes to see the planet again.

You can see the exact timings for more than 700 locations across the U.S. in a list compiled by the International Occultation Timing Association.

The best place to watch both the disappearance and reappearance of Venus will be from within the shadow of a large tree or building. Blocking out the sun will not only make it easier to see both the moon and Venus but also reduce the risk of sustaining eye damage by looking directly at the sun.

If you are struggling to see the occultation, try using your phone camera to zoom in on the waxing crescent to better locate and record Venus, Spaceweather.com recommends.

What the June 17 lunar occultation will look like

During the event, around 11% of the moon will be faintly visible in the daytime sky, according to Sky & Telescope. Around three-quarters of Venus will be visible — although it will look like a single spot to the naked eye — so the planet will shine much brighter than the moon. The pair will be collectively located around 38 degrees from the sun in the sky.

Venus will vanish behind the side of the moon opposite the illuminated crescent and will take around 30 seconds to disappear completely. It will then reappear above the crescent, similar to the iconic "Earthrise" photos taken by lunar astronauts, such as the Artemis II crew. (The exact spot where Venus disappears and reappears will depend on where you are in the world.)

If you miss this occultation or fancy another skywatching spectacle, be sure to head back outside later the same day, around an hour after sunset, when Venus, Jupiter and Mercury will shine alongside the crescent moon as it passes in front of the Beehive Cluster (also called M44).

A colossal chunk of sea ice roughly the size of Texas is missing from the west coast of Antarctica, and scientists fear it might never form again.

Antarctica is currently in winter, which runs from March to October on the southernmost continent. During the winter months, floating sea ice surrounding the continent typically grows, driving currents that regulate Earth's climate. But this year, there's a notable ice gap over the Bellingshausen Sea, on the western side of the Antarctic Peninsula.

Satellite observations have revealed that around 250,000 square miles (650,000 square kilometers) of sea ice hasn't formed yet, compared with the average amount of sea ice between 1991 and 2020, The Guardian reported last week. For comparison, the ice gap covers an area slightly larger than France or nearly the size of Texas.

Will Hobbs, a sea ice-ocean interaction scientist at the University of Tasmania, told The Guardian that he was "concerned" by the lack of sea ice and that it was "depressing." Hobbs noted that this year represents the third time in four years that the region's sea has been very low.

"I don't think we will see sea ice there any more," he said. "It's done."

Researchers still have a lot to learn about sea ice changes in Antarctica. Hobbs said that the sea ice loss was likely linked to changes in the ocean and that scientists are trying to determine whether global warming was a factor.

Sea ice has declined much more slowly in Antarctica than in the Arctic. But in recent years, scientists have been witnessing an astonishing change in the sea ice extent. One record low in 2016 was followed by another in 2022 and then a third in 2023.

Edward Doddridge, a physical oceanographer at the Institute for Marine and Antarctic Studies in Australia, told ABC News (Australia) that he was no longer surprised by sea ice loss.

"It's not good news, but it has become a pattern that we're expecting now," Doddridge said. "A warming world is going to have less sea ice."

The diminished winter sea ice is likely to have a variety of knock-on effects. For example, this area of sea ice normally provides important habitat for animals like krill and penguins. Sea ice also plays an important role in regulating the climate, including by driving key ocean currents, insulating the ocean from the sun, and protecting ice shelves at the mouths of glaciers.

Down the coast from the missing sea ice, researchers have warned that a key ice shelf is about to disintegrate from Antarctica's Thwaites Glacier — nicknamed the "Doomsday Glacier" because its collapse could raise sea levels by 2.1 feet (65 centimeters) in the coming centuries, flooding coastal communities worldwide. The ice shelf helps protect the mouth of the glacier by acting as a buttress, thereby restraining the flow of ice from the glacier into the sea.

Thwaites Glacier has been melting rapidly since the 1980s, which is part of a wider concern for the West Antarctic Ice Sheet that it helps to support. The collapse of such an ice sheet is considered one of the major environmental tipping points, or "points of no return," that humanity must avoid in the fight to rein in climate change.

The wreck of a Japanese prison ship that was sunk by U.S. warplanes and went down with more than 1,000 Allied prisoners of war in 1944 has been discovered in the Philippines.

The vessel was one of the notorious "hellships" used by the Japanese to ferry POWs between work camps. Many of the prisoners who died when the ship sank had worked on the infamous Burma-Thailand "Death Railway."

"Sadly, a lot of these prisoner transport ships were sunk by the Allies," expedition leader and American TV show host Josh Gates told Live Science. "The ships were painted to just look like military vessels, and they were inside the Japanese convoys — so the Allies thought they were legitimate military targets."

Gates teamed up with the Hellships Memorial Foundation, a U.S.-registered non-profit based in Subic Bay in the Philippines, to investigate the sinking of the hellship Hōfuku Maru. Its wreck had never been found, probably because searchers were guided by incorrect U.S. records to look too far north, he said.

But Japanese wartime records were more precise about the wreck's location, helping the team find the remains of the Hōfuku Maru in January, Gates said. His team has since made five dives to the wreck, which sits a few miles off the west coast of the main Philippines island of Luzon at a depth of about 160 feet (50 meters).

Prison ships

Japan used more than 130 hellships during World War II, but the wrecks of only a few have been found. Many hellships, including the Hōfuku Maru, were converted freighters. The Hōfuku Maru was used as a prison ship from 1942 until its sinking about two years later.

Gates said the vessel was part of a Japanese military convoy sailing from the Philippines to Japan when it was attacked on Sept. 21, 1944. U.S. warplanes had spotted the convoy, and one dropped a torpedo that cut the Hōfuku Maru in half. It quickly sank.

But the ship had roughly 1,200 Allied POWs on board, from the British and Dutch armies, many of whom had been forced to work on the Death Railway. Some were able to swim ashore, but they were recaptured by the Japanese. About 1,040 died in the sinking, Gates said.

War captives

The 1929 Geneva Convention placed strict limits on the use of prisoners of war for labor, but Japan was infamous for flouting these rules during World War II, claiming that it never ratified the convention and that wartime made POW labor important. Japan used POWs for slave labor on railways and docks, as well as in factories and mines. Of the roughly 132,100 prisoners captured from the United States and United Kingdom armies, nearly a third of them — about 35,000 people — died of exhaustion, malnutrition and disease.

Gates said the Japanese hellships used to ferry thousands of POWs between work camps were miserable places themselves: there was little light, air or food, and prisoners might be kept there for months. Human remains have been identified on the newfound wreck, and it will now be considered a war grave, he said. International conventions aim to prevent such wrecks from being disturbed.

The team first spotted the wreck with sonar, and then dove to identify parts of the structure that confirmed it as the Hōfuku Maru. They also mapped the wreck with a remotely operated underwater vehicle, which helped them determine that the ship had split into separate parts, just as accounts of the sinking had reported.

The Hellships Memorial Foundation would now work to try to locate the families of the victims, Gates said.

At age 19, John McFall thought he might never walk again after his right leg was amputated above the knee following a motorcycle accident. Fast-forward more than two decades, and he is now on the verge of becoming the first physically disabled person in space.

McFall, 45, is a British surgeon and former Paralympic athlete who won multiple medals as a T42-class sprinter. In 2022, he joined the European Space Agency's (ESA) Fly! program, which aimed to see if a person with a physical disability could live and work in low Earth orbit. And in February 2025, he became the first member of the program to be cleared for a potential future mission to space.

More recently, on June 2, the U.K. government announced that McFall had been selected as a prospective member of the first crew to live on Haven-1, an upcoming commercial space station from U.S. company Vast that is scheduled to be the first of its kind in low Earth orbit, if it launches on time early next year.

If everything goes according to plan, the roughly 30-day mission will help answer a series of interesting questions about how living in space might be both challenging and advantageous for people with physical disabilities.

Live Science spoke with McFall about what it would mean to break new ground, wearing a prosthesis in space and how microgravity might uniquely affect him.

Harry Baker: How did it feel to get the news that you might be going to space next year?

John McFall: Awesome. Very awesome, very exciting. And it feels like we're one step closer to realizing this amazing opportunity and achieving this very exciting milestone in human space exploration.

HB: What would it mean to you personally to become the first physically disabled astronaut in space?

JM: To me personally, it doesn't make a difference. In terms of "what an achievement for me," I don't tend to think of it like that. However, I am very aware that the broader message that it sends to wider society about what people are capable of — whether they have a disability or not — is very interesting and powerful. So I'm proud to be a very small part of that movement, if you like, and the journey of making society a more tolerant and inclusive place.

HB: What advantages do you think your disability might give you in space compared with other astronauts?

JM: It's a good question because we don't actually know. We can hypothesize, but until we actually get into space and conduct some science that's specifically relevant to my disability, we won't know. But there are some theoretical benefits.

One is that when you live in microgravity, you get a shift of fluid from the lower part of your body up into the upper part of your body and your cranium. This can cause swelling of the optic disk, which can temporarily affect vision. It's called spaceflight-associated neuro-ocular syndrome (SANS), and it affects around 70-75% of astronauts. I would hypothesize that, having a reduced lower limb volume to start with, you're going to get a proportionally smaller fluid shift in microgravity, relative to your physiological capacity to process it, reducing the risk of things like SANS.

Another is that in microgravity, because you're weightless, you're not using your bones as much, and your body naturally resorbs them. So your bones get weaker and thinner. And one of the byproducts of this is that you have to excrete a lot of calcium, and you do this via peeing it out. As it [calcium] passes through your renal system, or kidneys, this causes an increased risk of kidney stones in microgravity. So again, having lower bone mass to start with — but retaining the same physiological capacity to metabolically process calcium — there is potentially a lower risk of kidney stones.

So those are two small-but-hypothetical benefits of my particular disability in space. But the real answer is, we don't know until we do the science (i.e., urine samples, blood samples and eye examinations in orbit).

HB: How might space be more challenging for you than for other astronauts?

JM: Again, we don't know. The question is, do you really need both your lower limbs to help you stabilize and support yourself whilst your hands are doing tasks? And is having two legs useful in what we would call normal intravehicular operations [conducted inside the spacecraft], whether it be cargo operations, maintenance, this sort of stuff?

When we went through the feasibility initiative, trying to think of and work out all these scenarios, we couldn't really think of a disadvantage other than maybe having to work slightly harder.

HB: Will you be wearing a prosthesis in space?

JM: The plan is to wear a prosthesis. We deemed quite early on that wearing a prosthesis in a spacecraft would be a necessity, mainly at launch time. If there was an emergency that required me to get out of the spacecraft and get off the crew access arm and away from the launch site, it would be ideal wearing a prosthesis to do that.

But in space, we don't know whether it's going to be an advantage or be required for these intravehicular activities. Where I would definitely need to use one is on a long-duration mission where I need to exercise lots. I use a prosthesis to exercise on Earth, and I would use a prosthesis to exercise in orbit. However, short-duration missions [like this one] do not.

The prosthetics I use are modular, so I wear a socket — that's what's left of my leg goes inside — and then the hardware, what we call the terminal device, is attached to the socket. What I would envisage doing is always wearing the socket, because that way, you maintain consistency. But [for] the terminal device itself, I have a quick-change adapter that you can just unplug the device, and you can take it off and, likewise, put it back in again.

It's "plug and play," if you like, and [it will allow me to] make assessments of whether it's useful or not.

HB: Will your prosthesis need to be specially made for the trip?

JM: Not really. We are certifying a number of prosthetic hardware items to fly, but they're all what we call "commercial, off-the-shelf items." So they're products that are widely available.

However, there are some very small changes that we need to make to make them compliant with the safety requirements of the space station environment and the spacecraft, such as fireproof tape around certain parts of the device or changing the hydraulic fluid so it's less toxic in case there is a leak.

We're also doing a small amount of redesigning to the shape of the foot to make it more ergonomic to interface with things like rails and straps inside the space station, because you often slip your foot under rails and straps.

HB: Could anything you learn from your mission help physically disabled people back on Earth?

JM: Yeah, I think so, certainly from a prosthetics point of view. There are prosthetic developments that we have made that will benefit other prosthetic users in the future.

I mentioned this quick-change adapter. We have revised or reengineered this particular device to perform in a certain way, which I think will have advantages for a whole range of lower-limb amputees. The socket technology ‪—‬ the interface between my stump and the prosthesis ‪—‬ is [also] going to be redesigned and potentially has very beneficial applications for lower-limb amputees again.

HB: Are you hoping to be selected for more missions in the future? And would you like to become the first physically disabled person on the International Space Station (ISS) or the moon?

JM: Yeah, absolutely. I hope that we use this opportunity to demonstrate that it is very feasible, and I hope that that would put me in line for selection of missions in the future.

I would love to, in the future, potentially spend longer in space, demonstrating that it's possible for someone with a disability to live and work in space and cope with everything that comes with that.

And absolutely, I would love to go to the moon. You know, someone with a lower-limb disability, when you propose that against walking on the moon, it's quite a powerful statement, and I would love to do that.

Editor's note: This interview has been condensed and edited for clarity.

For decades, physicists have pursued a goal that sounds nearly impossible: to build a clock that keeps time using an atom's nucleus rather than the electrons orbiting it.

Now, researchers have demonstrated the first functioning nuclear clock ‪—‬ an advancement that could eventually lead to more robust timekeeping devices and new ways to search for dark matter and physics beyond the Standard Model.

"Having worked in this field for more than 15 years, it is just beautiful, how a very 'wild' idea such as manipulating an atomic nucleus with a laser has turned into reality," Thorsten Schumm, a professor of quantum metrology at the Vienna University of Technology and a member of the research team, told Live Science via email.

How is a nuclear clock different from an atomic clock?

Today's most accurate clocks are optical atomic clocks, which measure the frequency of electrons jumping between different energy levels inside atoms. These clocks are so precise that they would lose less than a second over a 100 million years.

A nuclear clock works similarly, but it uses a transition within the nucleus itself, where the nucleus jumps between energy levels. Because the nucleus sits deep inside the atom, it's far less affected by external disturbances from things like electric or magnetic fields. According to Schumm, the nuclear transition can be 1,000 to 10,000 times less sensitive to environmental noise than atomic transitions are.

"This means that it would be easier to stabilize a nuclear clock over long periods of time," Jacob Higgins, a postdoctoral researcher at Northwestern University who previously worked on thorium clock experiments at JILA in Colorado but was not affiliated with the study, told Live Science in an email. "The transition used for the nuclear clock experiment has a higher quality factor than optical atomic clock transitions, which means that in principle, it can be measured more precisely given the same amount of measurement time."

Together, those advantages could allow nuclear clocks to outperform even today's best atomic clocks according to Higgins.

Why thorium-229 is special

The nuclear clock relies on a rare isotope called thorium-229, whose nucleus contains an unusually low-energy excited state that can be manipulated with ultraviolet laser light.

For decades, scientists had suspected thorium had a low transition, but identifying and controlling it proved extremely challenging. Researchers spent years testing different thorium-containing materials, laser systems and detection methods before finally pinning down the transition.

"It was a long road," Higgins said.

One key advancement was the development of continuous-wave lasers that operate at the precise wavelength needed to excite the thorium nucleus. Before those lasers existed, researchers had to excite the nucleus and then wait several minutes for it to decay and emit a detectable signal. That process was too slow to build a practical clock.

"With the continuous lasers, we can measure the nucleus in absorption and get an immediate response, whether the laser is still at the right frequency (and if not, correct it back)," Schumm said. "Once we had that, it was 'just' implementing some electronics and atomization to have the clock stabilize itself to the nucleus."

Thanks to this set-up, the researchers kept the nuclear clock running continuously for 24 hours.

Unlike many optical atomic clocks, which require ultracold atoms to be suspended in a vacuum chamber, the thorium nuclei are embedded inside a crystal at room temperature.

Because the thorium transition remains stable inside a solid material, researchers may eventually be able to build compact clocks that are useful for navigation systems, telecommunication networks and data synchronization.

A tool for studying the universe

Some physicists are more excited about what nuclear clocks could reveal about fundamental physics, rather than the clocks' timekeeping abilities.

Atomic clocks primarily probe electromagnetic interactions involving electrons. Nuclear clocks, by contrast, are sensitive to the strong nuclear force, weak nuclear force and electromagnetism — three of the four fundamental forces of the universe, along with gravity. This can make them useful detectors of new physics, in a way.

"The nuclear clock is foremost a different clock, ticking on different fundamental physics mechanisms," Schumm said. "Essentially all modern theories beyond the standard model predict additional particles or 5th forces … which can be probed with the nuclear clock in some parameter regime."

Thorium-229 is particularly intriguing because the energy difference between its two nuclear states results from a delicate balance between electromagnetic and nuclear forces. Because those large contributions nearly cancel each other out, even tiny changes in the underlying forces could shift the clock's frequency.

"So small shifts in these forces — like if the nucleus were to couple to certain forms of dark matter or if there were an oscillation of a fundamental constant — will be amplified in our measurement," Higgins said.

Researchers, including Higgins, have already used early versions of the clock to place constraints on some dark matter models, and they expect its sensitivity to improve as the technology itself gets better.

Although the first functioning nuclear clock is a major achievement, these timekeepers remain in their infancy. Scientists still need to gain a better understanding of how the thorium transition responds to factors like temperature and magnetic fields while developing more powerful and stable laser systems.

"I think it will be many years before the thorium clock can compete with today's best optical atomic clocks," Higgins said, "but we will learn a lot of new science on the pathway to getting there."

The San Andreas and San Jacinto fault systems are at their highest levels of tectonic stress in 1,000 years, raising the threat of a major, imminent earthquake that could devastate Southern California, a new study finds.

The faults could rupture separately or together, thanks to an "earthquake gate" between them at Cajon Pass, where the San Jacinto fault splits from the main trace of the San Andreas fault. Researchers discovered that Cajon Pass can prevent or facilitate earthquakes moving between the faults, depending on how similar their stress levels are at the time of rupture.

And right now, the San Andreas and San Jacinto faults appear to have comparable, extremely elevated stress levels, potentially spelling trouble for Los Angeles, San Bernardino, Riverside and the Coachella Valley, the team warned.

"Our results show that stress levels on multiple fault segments are now at or above the highest values seen in the past millennium and that the region may be capable of a large through-going rupture involving both fault systems," study first author Liliane Burkhard, a planetary geologist at the University of Bern in Switzerland and at the University of Hawaii at Manoa, said in a statement.

The San Andreas and San Jacinto faults have caused 36 earthquakes with magnitudes of 6.4 or above in the past 1,000 years. Southern California's last "big one" was a magnitude 7.9 event in 1857, when a 205-mile (330 kilometers) segment of the San Andreas fault slipped horizontally between Parkfield and Cajon Pass. That rupture did not propagate through Cajon Pass, but a similar megaquake in 1812 did, suggesting this could happen again in what is now a much more built-up and densely populated environment, according to the study.

Almost 170 years have passed since the 1857 megaquake, raising fears that another huge earthquake could be due to hit soon.

To estimate this risk, Burkhard and her colleagues built a model replicating the last 1,000 years of major earthquake activity along the southern San Andreas and San Jacinto fault systems.

The researchers used observations such as tree-ring records and age data from sediments that have been displaced to reconstruct Southern California's earthquake history. They fed this information into the model, which simulated the accumulation, release and propagation of tectonic stress in the San Andreas and San Jacinto faults.

The results, published June 3 in the Journal of Geophysical Research: Solid Earth, suggest the San Andreas and San Jacinto faults are primed for an Earth-shattering rupture, which may involve the earthquake gate at Cajon Pass opening to unleash more destruction than a single-fault event would on its own.

If a rupture were to occur along the two branches of the San Andreas fault that connect at Cajon Pass, it would be a joint rupture, according to the study. If both branches of the San Andreas fault and the San Jacinto fault were involved, this would constitute a tripartite rupture.

The chance of each event happening and the timing of a potential rupture are unknown, but understanding how much stress is building up inside the system could help planners and policymakers prepare for whatever comes next, Burkhard said.

"What we can say is that the system is critically stressed, and that physics-based models like this one give us a clearer picture of the range of scenarios we should be prepared for," she said. "That information matters for hazard assessment, infrastructure planning, and emergency preparedness."

The researchers say their model could apply to other fault junctions and be used as a tool for hazard assessment globally. "We are using rigorous, quantitative science to better understand the risk facing millions of people," Burkhard said.

An elusive dwarf fox that was feared extinct has been photographed for the first time, after being spotted near a highway in Cozumel, Mexico.

The tiny animal was part of the mysterious Cozumel fox population, a potentially undescribed species that had not been officially sighted in more than 20 years.

Cozumel foxes live only on Cozumel, an island near Cancún. Researchers know very little about these mysterious predators, which are roughly 20% to 40% smaller than their gray fox (Urocyon cinereoargenteus) cousins that live on the mainland.

Park and museum officials spotted and captured the fox in 2023 and, after a health assessment, released it back into the wild. Researchers have now shared the photographs and documented the encounter in a new study published May 4 in the journal Neotropical Biology and Conservation.

Although the rediscovery confirms that Cozumel foxes are still alive, they are likely on the brink of extinction, the study authors noted; the photographs highlight the need for focused research and conservation efforts.

"The biggest challenge facing the Cozumel fox is that we still know almost nothing about it, including its remaining population size, distribution, or ecology," study first author Travis Bayer, executive director of the conservation organization Pathos Wildlife, said in a statement. "That uncertainty alone is dangerous, because it makes effective conservation extremely difficult."

Cozumel foxes are an example of insular dwarfism, an evolutionary process in which larger animals, including fox-sized mammals, evolve to be smaller after colonizing islands, where there are limited resources and less space than on the mainland. The foxes aren't the only mammals that have shrunk on Cozumel over time; other examples include the island's critically endangered pygmy raccoons (Procyon pygmaeus) and dwarf coatis.

Archaeological evidence suggests that Cozumel foxes have lived on the island for at least 5,000 years, likely since before the arrival of the Maya within the past few millennia, and potentially for tens of thousands of years before that. Prior to this rediscovery, the last confirmed sighting of a Cozumel fox was in 2001, according to the study.

The rediscovery began with reports of a disoriented animal wandering near the highway on the southeastern side of the island. Officials with the Parks and Museums Foundation of Cozumel located and captured the fox, an adult male, on Sep. 14, 2023. They checked its health and later released the fox in the Laguna Colombia State Reserve, a protected area just south of where it was captured.

Recent and historical sightings suggest that Cozumel foxes could have an extremely restricted range in the island's South, where nature is increasingly threatened by development, land-use change, invasive species and natural disasters, the study authors noted.

The researchers recommended surveys to determine the current distribution and size of the Cozumel fox population, along with morphological and genetic assessments to establish its evolutionary status and conservation efforts to protect its assumed habitat in southern Cozumel and minimize human-wildlife conflict.

"Ultimately, we hope this work helps move the Cozumel fox from a little-known, uncertain presence on the island to a better-understood key part of Cozumel's ecosystems," Bayer said. "We also hope it demonstrates that conservation is often most urgent when certainty is lowest and that uncertainty itself can be a call to action."

Since it launched from Kennedy Space Center on April 1, 2026, we've been treated to some truly incredible photos of NASA's historic Artemis II mission, including a dump of 12,000 images captured by the crew. But a blurry snap, which shows the crewed Orion capsule as nothing more than a handful of black and white pixels, is a contender for the most impressive Artemis II photo — because it was captured by an Earth-based telescope more than 200,000 miles (320,000 kilometers) away.

This makes the photo a candidate for the longest-distance image of humans ever taken from Earth. (Images like the "Pale Blue Dot," which were taken from space, don't count.)

The trippy image, shared May 6 by the National Radio Astronomy Observatory (NRAO), was captured by the U.S. National Science Foundation Green Bank Telescope (NSF GBT) in West Virginia. NSF GBT consists of a 328-foot-wide (100 meters) radio dish on a circular rail, making it the world's largest fully steerable radio telescope. It played a key role in tracking the Orion capsule (nicknamed Integrity) throughout the Artemis II mission.

The pixelated photo shows the radio waves emitted by Integrity as it slingshotted around the moon at around 2,000 mph (3,200 km/h) ‪—‬ as fast as a speeding bullet. The camper-van-sized capsule was approximately 213,000 miles (343,000 km) away when the image was captured on April 6 (the sixth flight day of the mission), meaning it was on the same side of the moon as Earth. It was, therefore, taken either just before or just after the crew temporarily disappeared behind the moon's far side and broke the record for the farthest distance traveled from our planet.

At first glance, the photo might not seem striking, but when you start to think about what you're actually looking at and the technology required to capture it, it becomes much more impressive.

"There are four people in those pixels," Will Armentrout, a NSF GBT astronomer who helped track Artemis II, commented to his colleagues when they first saw the image, according to an NRAO statement.

Those four people were mission commander Reid Wiseman, pilot Victor Glover and mission specialist Christina Koch of NASA, as well as mission specialist Jeremy Hansen of the Canadian Space Agency — each of whom broke a different individual spaceflight record during the mission.

Tracking NASA's return to the moon

The Artemis II crew launched to the moon on board NASA's mega Space Launch System rocket and splashed down in the Pacific Ocean on April 10, after reentering Earth's atmosphere at around 25,000 mph (40,000 km/h) — the fastest speed any humans have ever traveled.

Throughout the mission, spaceflight enthusiasts watched the livestream from Earth, keeping tabs on everything that happened, from early toilet troubles and lunar meteor strikes to a touching tribute to Wiseman's late wife and a rather awkward interview with President Donald Trump. But they were not the only ones watching.

The NSF GBT team was also keeping a close eye on Artemis II and helped to accurately track the crew's progress during six-hour observation windows on each of the five days Integrity was closest to the moon. The telescope's extreme sensitivity and precision helped provide crucial data that will help NASA prepare for future Artemis missions, which aim to establish a base on the moon.

"With the GBT, we were able to track the movement of the spacecraft within 0.2 millimeters [0.008 inches] per second of what NASA calculated in its projections," Anthony Remijan, the NSF GBT's site director, said in the statement. "It's like having a speedometer in your car that can track your speed within 0.0004 decimal places per hour."

This is a great example of how scientific institutions across the globe contributed to the mission.

"To get big things done like we're doing in this capsule … you need a big team behind you," Hansen said during an interview while on board Integrity.

This article was first published May 14, 2026.

Artemis II quiz: Is your knowledge of NASA's historic moon mission out of this world?

This awesome astronaut photo shows the striking symmetry of "twin" stratovolcanoes at the heart of Java, Indonesia. The parallel peaks are an eye-catching reminder of the region's extreme tectonic activity.

Mount Sundoro (also known as Sindoro or Sindara) on the left of the image, reaches a maximum height of 10,331 feet (3,149 meters). Its partner, Mount Sumbing, sits to the southeast (on the right of the image) and is slightly taller, at 11,056 feet (3,370 m) above sea level.

Both are considered active. Although Sumbing has not erupted since 1730, Sundoro has blown its top more recently, in 1971, and has experienced seismic activity as recently as 2012, according to the Smithsonian Institution's Global Volcanism Program.

The volcanoes' peaks are just 7.5 miles (12 kilometers) apart. A raised ridge with a major highway runs perpendicularly between them.

Each volcano also has a smaller, secondary cone on its flank left over from previous eruptions (to the upper left of Sundoro and the upper right of Sumbing in the image), and their orientations make the volcanoes look like mirror images of each other.

The slopes of both cones are covered with rings of dark-green forest that sharply terminate at their bases. The volcanic soils surrounding the mountains are excellent for growing crops such as rice, corn, coffee and sugarcane, which has led to the deforestation of their surroundings, according to NASA's Earth Observatory.

This matching coloration accentuates the similarities between the pair, especially when viewed from above.

One of the few differences between Sundoro and Sumbing is that the latter volcano has a sizable crater at its summit, which was carved out by the 1730 eruption. As a result, the larger volcano appears to have a darker point at its top.

The volcanoes are commonly referred to as "twins," due to their near-identical profiles. However, local people often call them "husband and wife," according to a local travel site. In this narrative, Sumbing is considered the husband due to its slight height advantage and "more masculine" profile.

Sundoro and Sumbing are part of the wider Dieng Volcanic Complex, which consists of around 20 volcanic cones stretching across central Java. Indonesia is also positioned along the "Ring of Fire," a roughly horseshoe-shaped arc of volcanoes that runs along a series of tectonic plate boundaries encircling the Pacific Ocean.

Over the past few years, there have been a number of significant eruptions in Indonesia, including a pair of violent blasts at Mount Lewotobi Laki-laki, on Flores Island, in 2024 and 2025. As of June 2026, there are seven ongoing eruptions in Indonesia — the most of any nation.

As the World Cup kicks off across the U.S., Canada and Mexico, scientists have predicted that extreme heat could play a decisive role in determining the outcome.

Nearly half of the scheduled matches — especially those in more southerly areas of the U.S. and low-lying parts of Mexico — have at least a 50% likelihood of "performance-impairing heat." To prepare, many teams have been training intensively in hot conditions, and during the tournament, they will have access to cold-water immersion tubs, ice vests and misting fans to help cool players down if they overheat.

Compared with these major sporting events, which have resources to adapt to extreme heat, community sports participants and recreational exercisers often have fewer options. This lack of adaptability may increasingly affect when, where and how people can safely exercise, especially as climate change makes extreme warming events more frequent and intense.

"The majority of people who play sport for competition or just for fun, recreation and leisure have a fraction of that power [of professional sports organizers] but face greater challenges and harms," Jessica Murfree, an assistant professor in the Department of Exercise and Sport Science at the University of North Carolina at Chapel Hill, told Live Science.

How hot is too hot for exercise?

Sports governing bodies typically use wet-bulb globe temperature (WBGT) to assess heat risk. It measures the combined impacts of temperature, humidity, direct sunlight and wind speed on the human body.

Taking humidity into account is key because, with more water in the air, it's harder for sweat to evaporate off the skin and cool the body. WBGT was developed by the U.S. military in the 1950s to prevent heat-related deaths in training camps. Nowadays, it also shapes safety guidelines for outdoor workers, as well as athletes.

The American College of Sports Medicine divides the U.S. into three regions to account for varying levels of heat acclimatization and defines WBGT ranges that pose a "very high" risk in each region. That threshold is a WBGT of 82.2 degrees Fahrenheit (27.9 degrees Celsius) or higher in Southeastern and Southwestern states, 79.9 F (26.6 C) in Central states, and 76.3 F (24.6 C) in Northern regions.

For unacclimatized individuals and those with poor physical fitness, the health risk jumps at lower thresholds.

Gulf Coast states — particularly Southern Texas, Louisiana, Mississippi, Alabama and Florida — tend to experience the highest WBGT values. High-risk conditions begin in May in South Texas and South Florida, before expanding northward and peaking in July and August. Studies suggest the number of extreme humid heat events has more than doubled in most parts of the U.S. since 1980, and that globally, climate change added roughly three weeks' worth of dangerous humid heat in 2024 alone.

An individual's overall health and fitness, hydration levels and amount of exertion need to be considered, and systemic factors like socioeconomic status also come into play, Murfree said. For instance, lower-income families are more likely to live in hotter urban environments and lack access to air conditioning, meaning they may already be experiencing heat stress at home.

While high humidity and heat make it so sweat can't evaporate easily, the body has other means to cool down. It also sends more blood to the skin, arms and legs, allowing heat to be released through the skin. But physical exertion in extreme heat makes this more difficult.

"We only have a limited amount of blood in our body, and we're simultaneously trying to use it to fuel the reactions in our muscles to be able to facilitate exercise, as well as send it to our skin to help us cool down," said Grant Lynch, a research fellow in the Heat and Health Research Centre at the University of Sydney.

When the body can no longer get rid of extra heat, symptoms of heat exhaustion ‪—‬ including dizziness, nausea, headache and muscle cramps ‪—‬ may set in. If the body continues to overheat, this can progress to heat stroke, a serious and potentially fatal medical emergency where a person's core body temperature rises to 104 F (40 C) or above. Heat stroke can cause central nervous system dysfunction and delirium, convulsions or coma.

In the U.S., exertional heat stroke is a leading cause of preventable death during sport and exercise and is a particular concern for youth athletes. Children, including teens, produce more heat relative to their body weight than adults do while sweating less. Additionally, they may feel less able to advocate for themselves on the playing field if they start to feel ill, Murfree said.

Reducing health risk in hot weather

The body can acclimate to extreme heat, to some extent. At the University of Sydney’s thermal ergonomics laboratory, researchers use a climate chamber to test the body’s capacity to adapt by increasing its blood plasma volume and lowering heart rate and resting temperature.

"We would have them come in for anywhere from five to 14 consecutive days of exposure," Lynch said. "They would be cycling or running for between 90 minutes to 2 hours every day, and the conditions would be [95 F to 104 F] 35 C to 40 C in the room for that entire duration."

The benefits achieved through this kind of heat acclimation aren't permanent. Research suggests that, for every two days spent in a cool environment, one day of heat acclimation is lost. For people exercising just a few times a week in hot weather, "it's pretty unlikely you are physiologically adapting as much as you think you are," Lynch said.

While WBGT is considered the "gold standard" for heat safety monitoring, the special device required to measure it may not be accessible to every community sports organization or individual person exercising. The danger, Lynch said, is that many people focus on ambient temperature alone to determine risk, when multiple factors are involved and can compound.

Sports Medicine Australia, the country's national body for sports medicine and sports science, developed a tool to calculate risk and suggest safety precautions. It combines data automatically extracted from weather stations — including ambient temperature, humidity, wind speed and solar radiation — with sport-specific information, such as typical uniforms and duration of activity.

Generally speaking, the sports body recommends staying hydrated before, during and after physical activity; wearing lightweight and breathable clothing; taking frequent rest breaks using ice towels and misting fans when possible; and delaying or cancelling games when the risk level gets too high. If someone begins to feel overheated, immediate action is important to prevent further heat strain.

"The most important thing to do, without a doubt, is to stop or reduce the intensity of the activity you're performing, seek shade, go into an area where you are not exposed to direct sunlight, and then douse the skin with water," Lynch said.

Heavy sweating, painful muscle cramps, nausea, dizziness, and cool, pale, clammy skin are all signs that someone may be suffering from heat-related illness. Heat stroke symptoms include a very high temperature; hot, dry skin or profuse sweating; confusion; and loss of consciousness. These symptoms should prompt immediate cooling with a cold water bath and emergency medical care.

While rescheduling events to cooler parts of the day is an option, heatwaves are already increasing in most regions and that trajectory is expected to continue as average global temperatures rise. So, some researchers and sports organizations are exploring infrastructure changes that could help: stadiums with shaded and green spaces, schoolyards with grass instead of concrete, and artificial turf with a built-in irrigation system for use in school sports fields.

Murfree said she would like to see heat safety training introduced in schools in areas prone to extreme heat in the U.S., similar to existing fire safety education.

"Sport often asks us to push ourselves harder, be faster and tougher," Murfree said. "It's OK to take breaks, stop, slow down, reschedule and advocate for our bodies and our wellness in the heat."

This article is for informational purposes only and is not meant to offer medical advice.

How much do you know about the greatest athletic feats of all time? Find out with our sports record quiz!

A clandestine excavation on the outskirts of Rome has brought to light a "splendid villa" that may have belonged to a member of the Antonine imperial family, according to archaeologists with the Special Superintendency of Rome. The remains of the first-century villa, which was previously unknown to archaeologists, include frescoed walls and mosaic floors that showcase the elite social status of the owners.

The villa was discovered at Castel di Guido, a village about 12 miles (19 kilometers) west of the ancient city walls of Rome. In ancient times, the area was known as Lorium, and it was frequented by prestigious Roman families, including the Roman emperors Hadrian, Antoninus Pius and Marcus Aurelius.

In February, the local police were alerted to illegal excavations at Castel di Guido on government-owned land, according to a June 15 translated statement from the Italian Ministry of Culture's Special Superintendency of Rome. The unauthorized excavations had been undertaken with a backhoe, which made deep cuts into the villa and left huge piles of dirt.

Superintendency archaeologists led by Alessia Contino carried out emergency excavations to document and stabilize the architecture at the site.

"Thanks to the local report and prompt intervention, it was possible to identify part of a large, previously unknown Imperial-period villa and uncover a splendid array of decorations, as well as the discovery of a statue in fine white marble," Contino said in the statement.

The excavation revealed the atrium at the entrance of the villa, two rooms decorated with frescoes and mosaics, and several other spaces related to the agricultural activities of the large, rural house. The villa was likely built in the early first century and abandoned in the third century.

The atrium's central impluvium — a marble basin in the center of many ancient Roman houses that collected rainwater from an opening in the roof — was surrounded by a floor decorated with bands of black-and-white botanical and geometric mosaics. The rear wall of the room, about 5 feet (1.5 meters) of which was still preserved, was painted red as part of a fresco that featured multicolor panels with human figures and botanical elements.

Surrounding the large room were four smaller ones, three of which still have preserved mosaic floors. One room includes nine black-and-white geometric panels, another includes black octagons on a white background, and the third has black rectangles.

Within the villa's central basin, archaeologists found a broken statue, about 31 inches (80 centimeters) tall, depicting a bearded man wearing a short tunic and carrying a basket with birds and fruit. The statue may represent Silvanus, the Roman deity of woods and other uncultivated lands, who watched over domesticated flocks of animals. Silvanus was also a companion of Bacchus (known in Greek as Dionysus), the god of wine and ecstasy.

The scale of the villa and the quality of the mosaics and frescoes suggest that the villa's owners were Roman aristocrats and may have even been members of the imperial family, according to the statement. In the Roman Empire, elite families like the Aurelii and the Arrii — the paternal and maternal families of Antoninus Pius, who reigned from A.D. 138 to 161 — lived in Lorium. Ancient sources suggest that Antoninus Pius spent his childhood in Lorium, built his imperial palace there, and died there at age 74.

Lorium was also frequented by Emperor Hadrian, who adopted Antoninus Pius to make him his heir, and by Marcus Aurelius, who was Antoninus Pius' nephew, adopted son and son-in-law. Because of Lorium's strong connection to the Antonine imperial dynasty, numerous villas and ancient estates have previously been discovered in the region.

But the newly uncovered villa "is another important piece of the puzzle," Contino said, "opening up new perspectives for understanding and preserving our history-rich territory."

Further work on the villa and its artifacts will help archaeologists date the building more accurately and work out whether it was abandoned when the imperial household was relocated out of Lorium, according to the statement.

Although work on the villa has not been completed, the public has a chance to visit the newly excavated villa and its mosaics on June 20 through a free archaeological hike and guided tour organized by the Special Superintendency of Rome.

From Augustus to Nero, see how much you know about ancient Rome's famous leaders with our Roman emperor quiz!

The Atacama Desert started forming about 20 million years earlier than scientists previously thought, long before the nearby Andes Mountains took shape, new research reveals.

Previously, the desert's hyperarid core was thought to have developed between 15 million and 20 million years ago, around the time the Andes were forming and cold ocean currents were establishing off the Chilean coast. But the new study suggests those ultradry conditions were present more than 40 million years ago, indicating that one of the world's oldest deserts is even more ancient than we thought.

"Our results indicate that the hyperarid core of the Atacama Desert was established in the Mid- to Late-Eocene [47.8 million to 33.9 million years ago], indicated by extremely low surface activity," study co-author Benedikt Ritter-Prinz, a geologist at the University of Cologne in Germany, said in a statement. "This makes it the longest continuously dry region on Earth and forces us to reconsider how and when such extreme environments develop."

The findings, published May 20 in the journal Nature Communications, could help scientists understand the global factors that contribute to desert formation and the evolution of life in dry regions.

Dating the Atacama's arid core

Covering up to 50,000 square miles (130,000 square kilometers) in northern Chile, the Atacama Desert is one of the driest regions in the world. The Andes to the east block precipitation from the Atlantic, and a cliff to the west blocks moisture from fog from the Pacific. The central, hyperarid region of the desert typically receives less than 0.2 inches (5 millimeters) of rainfall per year.

This lack of rainfall limits erosion and allows fluffy, flour-like gypsum soil to build up over time, according to the study. Once the soil reaches a critical thickness, it absorbs rain while leaving the desert surface virtually unchanged over long periods.

In the new study, Ritter-Prinz and his colleagues measured how long the surface of the desert's center had remained unchanged — a clue to when the hyperarid conditions set in.

The team collected quartz pebbles, which resist weathering and wind erosion, from different locations. That required an off-road venture deep into the desert.

"If you drive there, you can sink in up to 2 meters [6.5 feet] of this gypsum dust," Ritter-Prinz told Live Science. "So getting the samples is quite difficult."

Then, they measured the amount of rare isotopes, or versions, of the elements neon and beryllium in those samples. Called cosmogenic nuclides, those isotopes form when cosmic rays from outer space collide with objects on the planet's surface.

About 24% of the samples contained higher-than-expected levels of cosmogenic nuclides, suggesting they had remained on Earth's surface for longer than previously thought. While previous research estimated that the hyperarid core started drying out during the Early to Mid-Miocene epoch, about 20 million to 15 million years ago, the new findings suggest dry conditions may have been in place since at least the Late Eocene, about 40 million years ago.

"The idea just to have pebbles there, which are exposed for up to 45 million years … it's quite amazing," Ritter-Prinz told Live Science.

Instead of forming when the Andes rose and began blocking moisture from the ocean, the desert's core may have started to form when temperatures cooled following the Early Eocene Climate Optimum (54 million to 49 million years ago), a period characterized by extremely high atmospheric carbon dioxide and global temperatures 18 to 29 degrees Fahrenheit (10 to 16 degrees Celsius) above preindustrial levels. This suggests the formation of the Andes merely intensified the drying in the desert, rather than initiating it. Future work using climate models could help discern exactly how that happened, Ritter-Prinz said.

Learning how and when the desert formed could also help to explain the history of plant and animal life in the region.

"With this data, we can better understand how life adapts to specific events," and why certain species diverge, Ritter-Prinz said. For example, a shift to hyperarid conditions could cause certain migration pathways to close, eventually forming new species in isolated groups, he added.

The patient: A 44-year-old man in France

The symptoms: For two weeks prior to going to the doctor, the man had been feeling mild weakness in his left leg. There weren't any notable abnormalities in his medical history or neurological development, except for when a shunt had to be placed in his head when he was 6 months old. The shunt helped relieve fluid buildup in his brain, which had an unknown cause. When he turned 14 years old, the shunt was removed.

What happened next: When the man reported his leg weakness to medical practitioners, doctors ran CT and MRI scans of his head. They also performed neuropsychological testing, which revealed that the man's IQ was 75, below the average score of 100.

The diagnosis: Doctors determined that the patient was living with a brain that was at least half the average size.

The brain scans also revealed a large buildup of fluid in his brain, which allowed little room for tissue. This left the patient with just a thin sheet of brain tissue pushed up against his skull. The scans showed that the fluid-filled cavities in the brain — called ventricles — were extremely dilated. It's likely that this fluid accumulation drove the man's leg weakness.

The treatment: Doctors drained this excess fluid from the man's skull, which helped the patient regain some of his leg strength. In a case report published in The Lancet, the doctors wrote that a new shunt was also inserted inside the man's skull, and within a few weeks, the patient's neurological examinations — which were used to evaluate his leg weakness — returned to baseline. "The findings on neuropsychological testing and CT did not change," they noted, so the man's IQ remained about the same.

What makes the case unique: Over the course of evolutionary history, humans' brains became notably large compared with those of our relatives, leading to improved cognitive capacity and language acquisition. The exact reasons for this growth are not fully understood but are likely linked to a combination of environmental and dietary factors, among other pressures.

A human's brain also grows significantly within a person's lifetime, with the brain during adulthood typically being dramatically larger than the size of their brain as a newborn. In the man's case, it might have been expected that he would show deficits due to having a smaller-than-average brain. However, despite the smaller size of his brain, the man did not show any deficits and was working as a civil servant.

Had he not developed leg weakness, his small brain may well have gone unnoticed.

This article is for informational purposes only and is not meant to offer medical advice.

Some of the earliest Viking "pennies" were made with silver that contained melted-down coins from the Islamic world, a new study reports. The finding confirms the relationship between early Viking and Islamic silver, which was likely the result of long-distance trade.

The silver coins make up the Damhus hoard, a trove of 226 Viking Age pennies found near the town of Ribe on Denmark's Jutland Peninsula in 2018. The trove dates to between A.D. 830 and 850, which makes the silver pieces some of the earliest Viking coins ever discovered, according to the study, which was published June 5 in the journal Archaeometry.

Although the coins are formally called pennies, their weight in silver alone means they were much more valuable than modern pennies when they were made in the ninth century, study first author Thomas Birch, an archaeologist at the National Museum of Denmark, told Live Science. "The word comes from the Old English word 'pening'," he said – similar to "pfennig" in High German. A single pening was enough to buy ale, bread or simple tools.

The ancient coins are also remarkably well preserved after more than 1,000 years in the ground, Birch said. One side shows a face said to represent Wodan or Odin, the chief Norse god, while the other side portrays a stag.

Viking treasure

Crucially, the dies used to stamp the sides of the coins were replaced by similar dies as they wore out, resulting in tiny changes that modern scientists can identify, Birch said.

As a result, Birch and his colleagues saw that at least 30 dies had been used, and they estimate that hundreds of thousands of this type of silver Viking penny were produced by the single mint at Ribe, which was a major settlement at the time.

Early medieval Denmark was a center of the Norse world, and raiders from the coasts of Scandinavia were known as Vikings after the Old Norse word "vikingr," which meant something like "pirate."

The Vikings became notorious in 793 when they raided Christian monks on the English island of Lindisfarne. This event sparked the Viking Age, which ended in 1066 when a Viking army was defeated at Stamford Bridge in England only a few weeks before the Norman Conquest.

Ancient silver

Birch said the Damhus hoard came from a time when Denmark was divided among pagan Norse kingdoms, more than 100 years before their unification and Christianization under Harald Bluetooth.

Examination of 25 of the coins with X-ray fluorescence and other analytical techniques looked at the different isotopes — elements with different numbers of neutrons in their nuclei — of the trace elements mixed in with the silver. The results indicated that, in some cases, more than half of the precious metal had come from Islamic silver coins called "dirhams," he said.

The Viking coins were probably minted from ingots of silver produced outside Scandinavia, in part by melting down Islamic coins in bulk, Birch said, and these ingots had likely been traded to the ancient mint at Ribe.

"This silver has already had a life cycle; it's not coming straight from a mine," he said. "[The silver] has been made into dirhams and then been melted in a pot somewhere."

The coins in the Damhus hoard came from the precise time when silver from the Islamic world was becoming common in the Viking world, he noted; Islamic jewelry from that time has also been discovered in Scandinavia.

"We're right at the juncture of when we can see Islamic silver coming in," Birch said. "If these coins are being minted in the hundreds of thousands, that's a huge quantity of Islamic silver."

See how much you know about ancient norsemen with our Viking quiz!

For the first time ever, scientists have captured deep-sea footage of the elusive goblin shark, extending its known range far into the Central Pacific and down to nearly 6,560 feet (2,000 meters) below the water's surface.

The goblin shark (Mitsukurina owstoni) is a deepwater shark with an elongated snout and protrusible jaws that shoot out to snatch prey. The species, which has been around for about 125 million years, is described as a "living fossil." Until now, it had been seen alive only briefly, when it got hooked on fishing lines and hauled to the surface, according to a new study.

In the new footage, researchers documented two goblin shark sightings — one near Jarvis Island in the South Central Pacific Ocean and another at the Tonga Trench in the Southwest Pacific. Researchers suspect that goblin sharks live throughout the planet's oceans, as they have been caught in many different regions, but the specimen record is very sparse. So far, goblin sharks have been found only in narrow regions in the Atlantic and Indian oceans, as well as in small patches off the western U.S., Australia, Japan and Taiwan.

"The goblin shark is a deep-sea charismatic animal, and I never thought we'd see one alive," study co-author Alan Jamieson, the director of the Minderoo-University of Western Australia Deep-Sea Research Centre, said in a statement.

Not only was it fascinating to capture footage of goblin sharks in their natural habitat for the first time, but the specimen in the Tonga Trench was found swimming 2,300 feet (700 m) deeper than any other goblin shark, at around 6,550 feet (1,997 m), Jamieson said.

"On that expedition we filmed over 50 days of continuous footage between depths of 800 and 10,800 metres [2,600 to 35,400 feet] and this observation was a little over 20 seconds long which is [a] testament to how elusive this species is, and how special it is to have two observations in the same study," he said.

The researchers made the Tonga Trench observation in August 2024, while the Jarvis Island record dates to July 2019. The Tonga Trench shark was likely female and swam along the trench's northern slope, the team wrote in the study.

The Jarvis Island shark, on the other hand, was a male that was more than 11 feet (3.4 m) long and probably over 51 years old. It swam above an unnamed seamount at a depth of 4,058 feet (1,237 m), according to the study, which was published May 19 in the Journal of Fish Biology.

"New discoveries like this demonstrate that there is still so much to explore in our deep ocean home," study first author Aaron Judah, a doctoral student in biological oceanography at the University of Hawaii at Manoa, said in the statement. "Given the newly expanded geographic range of the goblin shark, this species can be included in regional management and a nation's biodiversity list."

Shark quiz: How much do you know about these iconic ocean superstars?

Towering 14,800 feet (4,500 meters) above sea level, the Tibetan Plateau, with its frigid temperatures and glacier-covered mountains, is the source of most of Asia's major rivers — the Yellow, Yangtze, Yarlung Tsangpo (Brahmaputra) and Lancang (Mekong) — which supply almost 2 billion people downstream, including the two most populous countries on Earth: China and India.

For that reason, the Tibetan Plateau is often called the roof of the world, the third pole and Asia's water tower.

But in recent years, the region has also earned a new moniker: Asia's power tower, thanks to its huge, untapped potential for generating hydropower.

Faced with water scarcity in densely populated, industrialized and irrigated regions of China; an insatiable need for energy; and a drive to eliminate fossil fuel use, Chinese authorities are pursuing a number of hydropower projects in the region. Together, they will not only tap the region's vast power potential but also attain unprecedented levels of control over vital water sources its neighbors rely on.

The government's flagship project is the Motuo (also called Medog) megadam project on the Yarlung Tsangpo River. The project officially started construction in July 2025, and its costs are staggering — estimated at up to $168 billion.

The megadam is slated to be completed in less than a decade and will dwarf all other hydroelectric projects in the world with its estimated 300 terawatts of annual power output — three times the output of the Three Gorges Dam on the Yangtze, the world's current largest dam, and more than the entire U.S. produced in net hydropower in 2024.

The dam is just part of a bigger Chinese initiative to transform its environment.

"You have a modern, powerful China who is in a way very, very confident of taming nature," said Tenzin Norgay, a researcher at the International Campaign for Tibet (ICT), a nongovernmental organization that works to promote human rights and democratic freedoms for the people of Tibet. The ICT is closely monitoring dam building in the region. "That's literally what they are trying to do, right?" Norgay told Live Science. "They are trying to tame nature."

But the massive project comes with huge risks for both people in Tibet and the hundreds of millions of people in countries downstream, including those in India and Bangladesh, experts told Live Science.

"Controlling [the] nature of the water or the river itself is a danger for the entire Himalayan belt particularly for countries like India, Bangladesh and to some extent also Nepal," said Jagannath Panda, head of the Stockholm Center for South Asian and Indo-Pacific Affairs at the Institute for Security and Development Policy, told Live Science.

Project of the century

China is the world leader in dam building. The government has constructed around 98,000 dams and reservoirs across China, including 40% of the world's largest dams, and numerous dams outside the country as part of its Belt and Road Initiative. But this new project is different.

"There's nothing on this scale, and nothing close to it," Brian Eyler, director of the Southeast Asia and energy, water and sustainability programs at the Stimson Center think tank in Washington, D.C., told Live Science.

The project will utilize Tibet's unique geography to full effect. In the project area, the Yarlung Tsangpo River (known as the Brahmaputra in India and Jamuna in Bangladesh) flows through the world's deepest canyon, called the Yarlung Tsangpo Grand Canyon, and rapidly drops around the horseshoe-shaped "Great Bend," before continuing to flow down and into India and, eventually, Bangladesh.

The project will dam the upper section of the river and divert the water through a series of tunnels that will be cut through the 25,500-foot-tall (7,800 m) Mount Namcha Barwa, before returning the water to a lower section of the river, circumventing the Great Bend. The project will likely have five dams in total, with hydropower stations inside the tunnels. The water will drop 6,500 feet (2,000 m) within 30 miles (50 kilometers) of tunnels, thereby generating a huge amount of hydroelectric power.

"It's really incredible that this type of project can be built," Eyler added.

The cascading dam system will require huge amounts of water to run effectively, meaning there will likely be a reservoir at the beginning, and so during the dry season the Great Bend will effectively run dry, Eyler said.

Mega project, mega challenges

Building such a large project in this region is fraught with risk, experts noted.

The Tibetan Plateau is one of the most seismically active regions in the world, driven by the ongoing collision between the Indian and Eurasian plates. The region has recently been rocked by several major earthquakes, including the 7.1 magnitude Dingri quake in January 2025, which damaged five dams in the region, and the 7.8 magnitude Nepal earthquake in 2015 that damaged a fifth of the country's hydropower capacity.

Parts of the Himalayas are unsuitable for dam construction due to the high risk of seismicity and its effects, researchers have warned, noting that dams are particularly vulnerable to earthquake-induced landslides.

In addition to naturally caused earthquakes, large-scale projects involving land excavation, tunneling and water redirection have the potential to trigger seismic activity, while the creation of reservoirs has been strongly linked with earthquakes in China.

Other natural disasters could endanger people beyond Tibet.

Glacial lakes — bodies of water created by melting glaciers and permafrost — can pose a problem to people downstream if they suddenly release their water and overwhelm dams. This scenario happened in northeastern India in 2023, causing a large, newly built dam to catastrophically fail, killing at least 46 people and impacting 88,000 more.

Climate change is accelerating glacial melt, meaning the threat will only increase as the region's glaciers are further destabilized, experts have warned.

Climate change could also render the dam obsolete sooner than anticipated. Dams typically function for around 70 to 100 years, experts told Live Science. Water levels in the Yarlung Tsangpo are expected to peak in 2060, so when water levels start to fall after that, the whole dam could become useless during dry periods because the water level will be too low to produce hydropower — a status known as minimum pool elevation. Water levels could even drop so low that they can't pass through a dam. This situation, known as "dead pool," is already an issue for some dams on the Colorado River.

The project will also affect Tibetans. "From our viewpoint, displacement of people around that and submergence of cultural sites" are the biggest issues, Norgay told Live Science.

However, the area is sparsely populated, and the reservoirs needed will almost certainly not be as big or as deep as reservoirs of other megadams. So although there will be an impact, it won't be on the scale of the 1.3 million people displaced by the Three Gorges Dam, Eyler noted.

Downstream impacts

Even without a climate-driven reduction in water, the river's flow will be transformed. To ensure a continuous, controlled flow of water through the dam, authorities typically fill reservoirs during the wet season and release water during the dry season. While this ensures that the hydroelectric dam can function, it inevitably impacts the river's natural flow and has knock-on effects for communities downstream. The filling-and-releasing process also raises the possibility of the upstream country — namely, China — "turning off the taps" to benefit the dam at the expense of other downstream water users.

"If a dam operator has an opportunity to take water during a time of drought, they're going to take at the expense of downstream users," Eyler said. "We've seen this happen in the Mekong, where the downstream was suffering drought, but China still filled its reservoirs," worsening drought in 2019 in Thailand, Cambodia and Vietnam.

In the case of the Motuo megadam, any change in water flow will affect India and Bangladesh. The Brahmaputra flows for about 1,800 miles (2,900 km), eventually joining with the massive Ganges River, and is a vital source of water and natural fertilizer for more than 130 million people. It provides India with 30% of its freshwater reserves, while Bangladesh is heavily dependent on the river to support its irrigated agriculture.

"The greatest ecological and environmental impact will be related to sediment flow. The Great Bend itself is a rich provider of sediment to the downstream [countries]," Eyler said. "Sediment is important for agricultural production. It's a very inexpensive natural fertilizer."

Sediment from the Brahmaputra is integral to building up the Ganges-Brahmaputra delta, helping the low-lying region stay above rapidly rising sea levels. The delta is home to nearly 200 million people — including in the megacity of Kolkata — and is considered one of the places most at risk from sea level rise. The Yarlung Tsangpo in Chinese-controlled territory provides up to 50% of the river's downstream sediment flow.

"River deltas are built by sediment flows pushing land out into the ocean year after year," Eyler said. "And either the dams themselves or the lack of flow within the Great Bend will cause a great reduction in the amount of sediment coming down."

The potential reduction in sediment could threaten food security in the downstream countries.

"Millions of people's lives are dependent on this river," Norgay noted.

India also plans to build major dams on the waterway, Norgay added, which could itself have negative impacts downstream.

Not true "green power"

The Motuo megaproject is just one of several new dams planned or under construction in Tibet; the ICT counts at least 193 dams in the region that have been planned or built since 2000, when China embarked on a policy of expanding infrastructure projects in the region.

The surge in hydropower projects is intended to help China move away from fossil fuels, experts told Live Science.

"It is part of a more widespread strategic vision where China is trying to become more sustainable," said Tom Harper, a lecturer in international relations at the University of East London who specializes in China.

One key to China's strategic vision is phasing out coal.

"This dam has been described as the coal killer. There are numerous coal plants that can be taken offline as a result of this and retired permanently," Eyler said. "When you bring in China's carbon emissions reduction goals, through 2050, the dam makes a lot of sense."

However, hydropower is not as sustainable as it's often portrayed, and it has environmental impacts. Large dams can cause severe environmental damage to river ecosystems. The creation of reservoirs can also release greenhouse gases as trees and plants are covered with water and subsequently rot, though this is less of an issue in cold places like the Tibetan Plateau, Darrin Magee, a hydropower expert at Western Washington University, told Live Science.

Though the authorities claim there will be no significant environmental impact from the dam, that's hard to believe, Eyler said. "Typically, the larger the project, the greater the impacts, and this is the largest dam system ever created."

Scientists also question the necessity of using hydropower to meet sustainability goals, when the Tibetan Plateau has huge, untapped wind and solar power potential.

Experts had different theories of what China would do with such a vast amount of energy generated in such a remote and sparsely populated area.

"There's certainly no need for it, right now or in the foreseeable future in the area where Motuo Dam is sited," Magee said. "But China solves that problem by building ultra-high voltage DC transmission lines at, at a rate that no one in the world is matching." These high-voltage lines transport energy from the west to east, bypassing local grid networks, he added.

Norgay and Panda both think Tibetans are unlikely to benefit.

The power will likely be moved east to power Chinese industry, they said, and it could also align with the political goal of further integrating Tibet into China, Panda added.

Eyler, meanwhile, thinks it will be used to power data centers in Tibet, "which can be built around the super dam, in a naturally cool and cold environment."

Better cooperation needed

There is little official information about the megadam for Chinese authorities, Eyler noted, and the lack of transparency is fueling fears. For example, Indian politicians have expressed concern that the megadam will give China full control of the river, and that China could potentially weaponize ‬the river by deliberately reducing the flow of water or by releasing large amounts of water in one go, thereby devastating downstream communities. Some researchers have called this possibility a "water bomb."

Eyler, however, said that this risk is low, and that the dam system's design means it cannot hold back enough water to cut off supplies downstream.

"I don't think that there's some type of nefarious plot out there from Beijing to bring these countries to heel by controlling the upstream of the rivers," he said. "China's top priority is to develop its economy, bring stability to the country, and building large dams on rivers is one way to do that."

The expansion of hydropower is a key aim for China in the next few years, as the country embarks on the 15th five-year plan from 2026. With shared water resources in short supply, better cooperation among neighboring countries is vital, experts said. Yet China and India share only limited data, Panda noted.

Some of the concerns from neighbors could be mitigated by better communication between stakeholders, Magee said. "Be more transparent with the data, bring more voices into the conversation, have some realistic assessment of both need for the project and the impacts."

But even with better communication, the megadam and other upcoming dams means China will still largely control the region's water resources due to its upstream position.

"This is a dam project which actually gives China the upper hand," Panda said.

Artificial intelligence (AI) has revealed hundreds of previously unknown earthquakes beneath the East Antarctic Ice Sheet, including some in an unexpected place: in the middle of a tectonic plate, far from a plate boundary.

The findings, published May 28 in the journal Science, reveal that Antarctica is more seismically active than previously thought and that new technologies can help to uncover hidden earthquakes in surprising locations.

In the new study, scientists used machine learning, a type of AI, to reanalyze seismic data taken from 49 seismic stations over the past two decades: one dataset from 2001 to 2004, and another from 2012 to 2015. The data revealed over 500 previously unrecognized earthquakes about 60 to 90 miles (100 to 150 kilometers) beneath David Glacier, which stretches nearly 700 miles (1,100 kilometers), bridging East and West Antarctica. This major outlet glacier drains about 4% of the East Antarctic Ice Sheet into the ocean, and its ice has thinned over the past several thousand years.

Earthquakes over 50 miles (80 km) deep are called intermediate-depth earthquakes. This type of earthquake is typically seen only at tectonic plate boundaries ‪—‬ specifically subduction zones, where one tectonic plate dives beneath another.

Yet the study showed that these earthquakes are happening in the middle of the tectonic plate, far from active plate boundaries.

"The earthquakes occur where the cold, rigid crust and upper mantle beneath East Antarctica meets warmer, softer rock beneath West Antarctica, and this contrast creates an abrupt change in tectonic strength," Long Ho, a University of Alabama geologist and first author of the new paper, told Live Science in an email. The detected earthquakes have magnitudes ranging from 1.6 to 3.5. The warm, buoyant material of the upper mantle extends beyond the edges of David Glacier from below, uplifting the edges of the nearby crust and bending them, and this concentrated stress causes the ground to shake, Ho explained.

It was surprising to find so many earthquakes at these depths, far from plate boundaries, Ho said, but similar earthquakes may be occurring in other geographic regions and going unnoticed given their small magnitudes. AI could help to identify those hidden quakes by reanalyzing past seismic data.

"As machine-learning tools continue to improve, they could reveal that deep, continental-interior earthquakes are more common than currently recognized," Ho said. "If so, the role of such events within the plate tectonics framework may need to be re-evaluated."

The results also show that Antarctica is more dynamic than previously thought. "Antarctica was [long] considered to largely lack earthquakes," Richard Alley, a glaciologist at Penn State who was not involved in the new paper, told Live Science in an email. "Now, we know that the apparent lack of earthquakes was really a lack of [tools] to listen to earthquakes." The data from this paper were collected between 2001 and 2004 and are now yielding new results as modern techniques have been developed to analyze the data, Alley said.

The detected earthquakes are not strong enough to threaten the overlying ice sheets or the Antarctic ecosystem, Ho said, so the research team is not concerned about that.

Next, Ho hopes to explore how the enormous weight of the Antarctic Ice Sheet might contribute to the location of earthquakes, and how changes in the ice sheet could affect underlying seismic activity.

It's still puzzling that seismic activity is concentrated at David Glacier rather than spread along the mountains in this region, Alley said, adding that the answer could be linked to the recent history of the ice sheet growing and shrinking, or to a longer history of the ice sheet eroding.

"I worry a lot about the ice sheet," Alley said, "and I hope work like this is continued and expanded, to help us understand the history and improve our understanding of possible futures."

How much do you know about Earth's frozen continent? Test your smarts with our Antarctica quiz!

A rare lunar meteorite that fell to Earth holds evidence of a previously unknown "impact event" that rocked the moon roughly 3.5 billion years ago, researchers say. Studying this ancient impact provides fresh insight into how the solar system was behaving in those early days — about the same time life on Earth began to appear.

In the new study, scientists looked at a lunar meteorite found in northwest Africa. The meteorite, called NWA 12593, contains information about three separate lunar impacts, but the researchers focused on the earliest of these crashes, the team reported in the journal Geology.

"On Earth, the first fossil evidence of life shows up around 3.5 billion years ago, meaning that life is emerging and evolving before then, " Carolyn Crow, first author of the study and a planetary scientist at the University of Colorado Boulder, said in a statement. "The question that we often have, even going back further, is what was the impact record when life was emerging? It is important for understanding how life is taking hold… The cadence of these catastrophic events is an important part of the equation."

In the study, the scientists used radiometric dating on the meteorite. This method charts the decay rate of radioactive materials in the sample, allowing the team to estimate the first impact at 3.5 billion years ago — roughly 1 billion years after the solar system formed.

The meteorite contained cubic zirconia, best known on Earth for its resemblance to diamond. But in the ancient meteorite, this material tells a different story: that the moon's surface became molten through the impact, because cubic zirconia forms only at extremely high temperatures. While the material dissipates at the ultracold temperatures found on the moon, the scientists found its presence through traces of its recrystallized products.

The impact occurred at roughly the same time as other huge impacts, both on Earth and on a very large asteroid called Vesta, that have been identified in independent research. To find three impacts on three different worlds so long ago is rare, because erosion and other processes tend to erase the evidence.

"It's not very common, which is why we're very excited about it," Crow said. "It's pretty rare to have all three records line up like this." The team expects that making deeper comparisons between the impacts will show more about how the solar system was changing 3.5 billion years ago, as the number of asteroids in the neighborhood diminished along with impacts.

Scientists often say the early solar system was a collection of gas and dust that gradually grew into smaller, comet-like and asteroid-like bodies. Over time, a subset of those bodies got even larger (through collisions and accretions) to become today's planets and moons.

The other two impacts on the meteorite were a breccia (rock melt) formed after the big collision 3.5 billion years ago and a third collision that sent the meteorite blasting off the moon and into an Earthbound trajectory.

How much do you know about the moon? Test your lunar smarts with our moon quiz!

This rare example of an Aztec ritual mask was carved from wood over five centuries ago to represent Mictlantecuhtli, the god of death and lord of the underworld, who was always depicted with a skull face. Mictlantecuhtli was responsible for the souls of people who died "heroic deaths" in battle, sacrifice or childbirth, helping them navigate the nine levels of the underworld and find eternal rest.

According to The Walters Art Museum in Baltimore, which has the mask in its collection, the carved wooden artifact measures 6.75 by 5.5 inches (17.2 by 14 centimeters). The sunken eyes with black pupils and the triangular nose give the mask a skull-like quality. On the cheeks, experts discovered traces of small, reddish dots that likely represent splotches of decay associated with Mictlantecuhtli. His teeth have been painted with vertical black lines, and both ears appear to have been pierced, as Mictlantecuhtli was often depicted with ear spools made of human bones.

Masks were an important part of ancient Aztec religion. In some rituals, people would wear masks of key deities, including carved skulls representing death, to transform themselves into supernatural beings. But because this particular mask of Mictlantecuhtli has no eye holes, it was probably affixed to a post or statue rather than worn, according to The Walters Art Museum, making it a rare example of a sculptural Aztec mask.

Mictlantecuhtli was a formidable part of the Aztec pantheon. He was said to be at least 6 feet (1.8 meters) tall and wore a necklace made of human eyeballs. When his full body was depicted, Mictlantecuhtli was shown with his arms raised, ready to tear apart the dead who entered his domain of Mictlan, the Aztec underworld. People who worshipped Mictlantecuhtli even practiced ritual cannibalism at his temple on occasion, according to Michael E. Smith, an emeritus archaeologist at Arizona State University.

One key myth featuring Mictlantecuhtli, according to University of California, Riverside archaeologist emeritus Karl Taube, involves the creation of the generation of people living in the world today. In this origin myth, the feathered serpent deity Quetzalcoatl, the Aztec god of earth, water and wind, among other things, must go to the underworld to retrieve the bones of all the deceased ancestors who had been turned into fish by a massive flood. Mictlantecuhtli agrees to give up the bones if Quetzalcoatl can blow a conch shell trumpet while journeying around the underworld.

Mictlantecuhtli secretly gives Quetzalcoatl a shell without holes, but Quetzalcoatl quickly fashions it into a trumpet, completing the task. Mictlantecuhtli is enraged and doesn't want to hand over the bones, but Quetzalcoatl takes them anyway. He brings them to Cihuacoatl, the fertility goddess, who grinds down the bones and places them into a sacred container. All of the Aztec gods gather around the vessel and shed their blood into the bone meal, creating humans.

This myth demonstrates that, although Mictlantecuhtli was associated with the dead in Aztec mythology, he was also connected to the concepts of regeneration and resurrection.

For more stunning archaeological discoveries, check out our Astonishing Artifacts archives.

Humans are the only species known to use fully symbolic language: a system capable of expressing abstract ideas, imaginary worlds and endless combinations of meaning. But how did we get there?

The origins of language have fascinated philosophers, scientists and storytellers for thousands of years. Despite all our advances in linguistics, archaeology and cognitive science, we still don't know exactly how language began.

That uncertainty hasn't stopped people from trying to solve the mystery. In fact, some of the earliest theories of language's origins are among the strangest and most entertaining ideas in the history of science.

Bow wow, ding-dong

In the 19th century, scholars proposed a flurry of curious theories to explain how speech first emerged. Many of these theories were given playful nicknames by the German philologist Max Müller, who intended them partly as satire. Yet the theories were genuine attempts to tackle one of humanity's biggest questions.

The most famous is probably the Bow-Wow Theory. This suggested language began through imitation of natural sounds. Early humans, according to this theory, copied the noises around them: animal cries, splashing water, thunderclaps and birdsong. Words such as "buzz," "hiss," "bang" and "splash" seem to support the idea because they sound like what they describe.

But there is a problem. Different languages hear the same sounds differently. English dogs go "woof" or "bow-wow," but in Turkish they go "hev-hev," while Indonesian dogs go "guk-guk." Even animal noises, it turns out, are filtered through culture and language.

And onomatopoeic words (words that imitate sounds) make up only a tiny fraction of our vocabularies. Most words sound nothing like their meanings. For instance, there is nothing inherently tree-like about the word "tree."

That brings us to the Ding-Dong Theory, which argued that sounds and meanings are naturally connected in some deeper, almost mystical way.

Some words do seem to fit their meanings uncannily well. "Mini," "teeny" and "itsy-bitsy" feel small and delicate. "Lump," "rump" and "plump" sound heavier and rounder.

Modern linguists call this sound symbolism. One famous experiment asked participants to match two nonsense words, "bouba" and "kiki," to two shapes: one rounded and one jagged. Most people matched "bouba" with the soft shape and "kiki" with the sharp one.

The effect is real, but it is limited. Most language still appears to be arbitrary, which means there is no natural reason why a particular sound should mean a particular thing.

Pooh-pooh, la-la, ye-he-ho

Other theories focused less on imitation and more on emotion and social interaction.

The Pooh-Pooh Theory proposed that speech began with instinctive emotional cries such as "ouch," "oh" or perhaps less publishable exclamations uttered after stubbing a toe. According to this idea, language evolved from spontaneous vocal reactions to pain, surprise, fear or joy.

Again, though, there are complications. Interjections vary widely across languages. English speakers say "ouch." Greeks say "aou." Czechs might exclaim "ach." Emotional sounds are not nearly as universal as they seem.

Then there is the wonderfully named Yo-He-Ho Theory, which suggested language emerged from rhythmic chants used during collective labor, like sailors chanting "yo-heave-ho" while hauling ropes, or workers singing together to coordinate physical effort.

The theory may sound quaint, but modern researchers do think rhythm, cooperation and social bonding played important roles in human evolution. Language is, after all, deeply social.

Another proposal, the La-La Theory, linked language to music. Charles Darwin entertained the possibility that speech evolved from musical calls used in courtship and emotional expression. Before humans spoke, perhaps we sang?

Some modern theories echo this idea. One hypothesis suggests that, as early humans began walking upright, parents increasingly needed to soothe babies from a distance. Sing-song vocalizations, cooing and proto "baby talk" may have helped strengthen emotional bonds and eventually paved the way for speech.

Gestures, symbols and brains

Today, most scientists think no single theory fully explains language origins. Instead, language probably emerged gradually through a combination of gestures, vocalizations, facial expressions, social cooperation and increasing cognitive complexity.

Some researchers argue that language began with gestures before shifting to speech. Others believe language evolved as a tool for social bonding, allowing larger groups of humans to cooperate and share information. Still others see language as tied to the evolution of symbolic thought itself: our ability to imagine, plan, remember and communicate abstract ideas.

Biology is also a factor. Humans have developed unusually precise control over the tongue, lips and vocal tract. We have evolved specialized brain regions linked to language processing.

But anatomy alone cannot explain language. Parrots can mimic speech sounds. Many animals communicate. None, however, appear to possess grammar and symbolism on the human scale. And, frustratingly, early language leaves no evidence behind. Spoken words don't fossilize.

That lack of evidence is one reason the topic became so controversial that, in 1866, the Société de Linguistique de Paris banned discussions about language origins altogether, dismissing the field as hopelessly speculative.

Of course, theories about language origins also appear in religion and mythology. In Greek mythology, the messenger god Hermes was associated with language and communication. In the Hindu tradition, the goddess of knowledge and speech Saraswati bestowed Sanskrit upon humanity. In the Judeo-Christian tradition, language was a gift from God, who enabled Adam to name the animals in the Garden of Eden.

These stories reflect something deeply human: our urge to explain where language came from, because language itself feels almost magical. Every theory of language origins captures a small piece of the puzzle. Imitation, emotion, rhythm, music, gesture, cooperation and symbolic thought probably all played some role.

But none can provide a complete answer. The truth is that language evolved so long ago, and likely so gradually, that we will never pinpoint a single moment when it began, unless someone invents a time machine.

The birth of language will probably remain one of humanity's greatest unsolved mysteries. Still, the theories themselves tell us something important. Humans are always trying to explain what makes us human. And language may be the most human thing of all.

This edited article is republished from The Conversation under a Creative Commons license. Read the original article.