Archaeologists have unearthed the oldest evidence of cannabis use from a 2,800-year-old monumental tomb in Siberia. The presence of plant seeds in the grave and chemical traces of the drug in mummy hair suggest people practiced a funeral ritual that may have involved a grim practice: calming human sacrifice victims with cannabis.

In a study published Thursday (Nov. 5) in the journal Science, researchers investigated the contents of a "royal mound" burial at the Tunnug archaeological site in the Uyuk valley of southern Siberia. Archaeologists discovered four wooden structures containing several log coffins in the middle of the mound. On top of the wooden burial structures were the skeletons of horses that once formed a "spectral cavalcade," a Scythian funeral tradition that involved sacrificing horses and humans. And inside the burial structures, the archaeologists discovered piles of tiny seeds from the plant Cannabis ruderalis, a wild type of cannabis or marijuana.

Cannabis likely originated in Asia and was cultivated thousands of years ago for various purposes, including for ropes and textiles, and 6,000 years ago as an oilseed crop, according to the study. But it's unclear when people learned about the psychoactive properties of the plant. In the fifth century B.C., the ancient Greek historian Herodotus wrote that the Scythian nomads inhaled the fumes from burning hemp seeds. And evidence of cannabis use was previously discovered in a cemetery in China dated to about 500 B.C. The new study, however, pushes back this date by three centuries.

Researchers discovered more than 1,000 whole cannabis seeds and around 500 partial seeds in the Tunnug burial mound, and they carbon-dated them to between 800 and 760 B.C. They also recovered several human hair samples from the grave. An analysis of the hair revealed signals matching cannabinol and THC (tetrahydrocannabinol), psychoactive chemical compounds found in cannabis. The tests could not determine how much of the drug people consumed, however.

"The molecular traces in the hair and the cannabis seeds come from the same grave and suggest that cannabis was used for its intoxicating properties," study first author Gino Caspari, an archaeologist at the Max Planck Institute of Geoanthropology in Jena, Germany, said in a statement.

But given the burial context of the discovery, the use of cannabis may have had a darker purpose.

"In this princely tomb, the burials were accompanied by extensive horse sacrifices and, most likely, human sacrifices as well," Caspari said. The tradition of human sacrifice, in particular, "would have potentially made the plant a useful agent to calm individuals who were to be included in the rituals," the researchers wrote in the study.

The new study confirms the ancient use of cannabis in funerals in Central Asia and extends the date back to 2,800 years ago, the researchers noted. Future work is planned but will focus on other aspects of ancient cannabis.

"We have already begun sequencing some of the plant samples," Caspari said. "This will help us learn more about the history of the domestication and spread of the crop soon."

An Elizabethan padlock has been opened for the first time in more than 400 years after researchers used X-ray imaging techniques to crack its four-letter combination.

The brass lock was part of the Ann Francis treasure hoard, named after the British merchant ship that wrecked during a storm off the coast of Wales in 1583. Researchers believe the lock once secured a chest aboard the ship, before becoming separated from whatever riches it was protecting.

Some of the Ann Francis' cargo was recovered at the time of the wreck, while the rest was claimed by the sea. In recent decades, dredging and storms on Margam beach in South Wales have exposed some of the ship's lost treasure.

Between 1996 and 2017, metal detectorist Peter Hughes found the lock and much of the hoard, which included gold and silver coins. The lock was subsequently acquired by Amgueddfa Cymru — National Museum Wales, which worked with researchers at Cardiff University in Wales to decipher its combination.

To study the lock's internal mechanisms, the team used micro-CT scans, which make thousands of X-rays that can then be configured into a 3D digital image. By matching internal notches to external letters in the digital 3D image, the researchers were able to decipher the correct four-letter code — "ANCE" — and open the lock.

"We normally use this technology to study bones and other biological structures, so investigating a 400-year-old padlock was certainly a first for us," David Williams, a research associate at the Musculoskeletal Biomechanics Research Facility at Cardiff University, said in a statement. "It's not every day you get to solve a 400-year-old mystery!"

Smugglers' ship

The Ann Francis was owned by Francis Shaxton, a merchant and notorious smuggler. Francis claimed the ship was sailing along the eastern English coast from King’s Lynn to Hartlepool, when it was actually traveling in the opposite direction, heading to Spain to deliver a cargo of wheat. Spain was dependent on grain shipments at the time and paid for such shipments in gold and silver from colonial conquests in Central and South America, according to Amgueddfa Cymru.

The ship was traveling back from Spain to England when, on the evening of Dec. 28, 1583, it was caught in a violent storm. After heading off course, the ship ended its journey in ruin off Margam beach.

A parish register noted the loss of 14 sailors during the same month as the wreckage, which could have been The Ann Francis's crew, according to Amgueddfa Cymru. The deaths were blamed on the nefarious work of a supposed witch.

Locals were quick to loot the Ann Francis wreck before a legal dispute ensued over who had the right to its goods. One Welsh lord claiming the wreck made an inventory list of items he impounded, which included cannons, guns, a piece of mast, Spanish silver and three chests with their locks broken. The newly cracked lock could have originally secured one of these chests, according to Amgueddfa Cymru.

Centuries after the ship was wrecked, Hughes found the lock near a previously undiscovered stash of Spanish silver coins and coin weights while metal detecting on the beach.

"When I found the lock I was immediately astonished by the incredible workmanship and its astonishing condition," Hughes said. "When I moved the ring dials of the combination they turned with ease after over 400 years beneath the sands and I was left in disbelief."

Hughes said he attempted to open the lock himself over many years but could never find the right combination. After Amgueddfa Cymru acquired the lock, staff were concerned that they could hear grit moving around inside the dials, and with more than 1,000 possible combinations, they didn't want to cause any damage.

The micro-CT scans offered a nondestructive view inside the lock, and an opportunity to finally identify the correct four-letter combination.

"Elizabethan combination locks are known in Britain, but this one is in exceptionally good condition and is associated with a dated wreck, making it a unique find and the code a tantalising mystery to solve," Alastair Willis, the senior curator for numismatics and the Welsh economy at Amgueddfa Cymru, said in the statement. "Of course, now we've solved it, we are left wondering if the code meant something to its owner."

Archaeologists investigating the genomes of a dozen people buried in an abandoned Roman-era settlement in northwestern Germany have discovered a surprising organism lurking in one man's remains: a rare strain of Mycobacterium leprae, which causes leprosy.

This strain of leprosy has never been seen in this part of Europe before, which hints that the individual had traveled and interacted with people from across the Roman world. The man was buried in a wooden boat surrounded by unusual objects, indicating he was a high-status person, according to a research study.

"The results were particularly striking in the case of one individual," study co-author Ben Krause-Kyora, an archaeologist at the Institute of Clinical Molecular Biology (IKMB) at Kiel University in Germany, said in a Nov. 3 statement. "He could, for example, have been a mercenary in the Roman army who later settled between the Elbe and the Weser [rivers]."

In the study, published online Oct. 15 in the journal iScience, Krause-Kyora and colleagues analyzed the genomes of people buried at the coastal settlement of Fallward. The settlement originated in the first century B.C. but gradually declined and became a cemetery by the fifth century A.D. Among the 200 cremation burials and 60 inhumation burials originally excavated in the 1990s was a distinctive grave made from a wooden boat.

The oak boat was over 13 feet (4 meters) long and sealed with a roof-like structure, the researchers said. It held the skeleton of a man who was about 50 years old when he died some time between A.D. 425 and 450. His grave goods included a small box shaped like a water bird, an ornate chair or throne carved out of alder wood, a bronze basin and a maple stool with a hunting scene and a runic inscription. The maritime artifacts coupled with the man's well-developed upper arm bones suggest he may have worked as a fisherman or boatman just before he died, the researchers wrote.

"The grave goods placed in the tomb aroused particular scientific interest," study co-author Hauke Jöns, an archaeologist at the Lower Saxony Institute for Historical Coastal Research, said in the statement. "The man possessed a late Roman military belt, which suggested that the deceased had had connections across great distances."

A rare form of leprosy

To learn more about this unusual burial and to determine where the man was from, researchers analyzed his DNA.

"Genetic analyses confirm that a man buried at Fallward originated from the Danube region," study first author Daniel Myburgh, an ancient DNA researcher at IKMB, said in the statement. "He was also infected with a very rare leprosy pathogen."

The researchers found the DNA of the bacterium M. leprae in one of the man's teeth and in a foot bone. Because the leprosy DNA was so well preserved, the researchers were able to narrow down the strain that had infected him. This strain of leprosy may have evolved in Egypt around the fourth to second centuries B.C. and had never before been found in Central or Northern Europe, according to the statement.

But the man showed no signs of leprosy lesions in his skeleton, the researchers said. Leprosy first attacks the nerves and skin, but it can eventually eat away at the bones of the skeleton, particularly affecting the nose, jaw, hands and feet.

"Leprosy is a chronic disease," study co-author Almut Nebel, a biologist at IKMB, said in the statement. "Either he was affected by an asymptomatic form of the disease, or the disease had so far only affected soft tissues. He may have travelled long distances whilst carrying the disease."

While the researchers don't know exactly what happened in this man's life, they suggested he might have been a mercenary who served in the Roman army and later retired to northwest Germany, becoming a high-status member of the community who was honored with an alder-wood "throne" in his burial. But he also may have acquired the Roman belt through trade, inheritance or as a war trophy, the researchers wrote.

Either way, the man's skeleton and his grave goods suggest that northwest Germany had long-distance connections in Europe even after the fall of the Roman Empire, according to the statement.

What do you know about the bones in your body? Test your knowledge with our human skeleton quiz.

Across 53 challenging days between fall 2020 and spring 2021, a 360-pound (160 kilograms) young male grizzly bear nicknamed "Lingenpolter" tried to cross Interstate 90 in western Montana 46 times. High-resolution GPS tracking showed him moving parallel to four lanes of roaring traffic, bouncing off the highway like a furry pinball as he searched for a gap.

Eventually, Lingenpolter beat the odds, probably by slipping under a river bridge. But his hero's journey shows what a formidable barrier a busy highway can be for wildlife, Cecily Costello, a research wildlife biologist at Montana's Department of Fish, Wildlife and Parks, told Live Science. "It is easy to imagine the difficulty this grizzly bear experienced trying to reach the other side," Costello said.

This past May, another grizzly wasn't so lucky. Braving a crossing near one of Lingenpolter's attempts, the 27-year-old male bear was struck and killed by a truck, triggering a multicar rollover.

It's crucial for grizzly bears (Ursus arctos), also known as brown bears, to have room to roam. When they can't move between populations to mate, small groups get genetically isolated. And what's true for bears can also be true for other wildlife. "It's really challenging to be a small, fragmented population," said Michael Proctor, a wildlife biologist at Birchdale Ecological Ltd., a Canada-based environmental consulting firm. Such fragmentation is "one of the mechanisms by which we lose entire communities, and sometimes whole species," he told Live Science.

Nowhere is this challenge more urgent than in the 2,100 mile long (3,400 kilometers) region stretching along the spine of the Rocky Mountains between Yellowstone in Wyoming and the Yukon in northern Canada. The area, which spans five U.S. states, two Canadian provinces, and more than 75 Indigenous territories "represents the most intact, connected, wild, large mountain region in the world," Jordan Reeves, program director of landscape connectivity at the Yellowstone to Yukon Conservation Initiative (Y2Y), which aims to secure connectivity throughout the region told Live Science.

But as highways, rail lines, and human development fragment its valleys, maintaining connected pathways for grizzly bears across this landscape has become a challenge.

Grizzlies range across vast, diverse terrain, spanning high-elevation alpine habitats, mid-mountain slopes, and low valley bottoms, which means safeguarding their movement can also protect passageways for coexisting species, including wolverines, mountain goats, elk and bighorn sheep, Proctor said. That's why researchers are trying to understand why, where and when grizzlies move. And what stops them in their tracks.

"We're looking at how a bear sees the world," Andrew Derocher, a bear biologist at the University of Alberta who has used GPS collars on grizzly bears to trace their movements, told Live Science.

Nature versus nurture

When Sarah Sells started her graduate studies in animal behavior, her supervisor told her to "try to crawl into their fur brains and understand how they think," Sells told Live Science. Although we can't recreate exactly what's going on between a grizzly's ears, GPS collars that track animal movement hourly can tell scientists a lot about how animals behave, said Sells, who is currently the assistant unit leader of the U.S. Geological Survey's Montana Cooperative Wildlife Research Unit.

That tracking data is starting to produce an incredibly detailed picture not just of where bears go but also how and why they're making those choices.

"Bears are food finding machines," Chris Servheen, a bear biologist with the International Union for Conservation of Nature's Bear Specialist Group, told Live Science. "So remembering where they found food is critical to their success in life."

Using a combination of telemetry data (information collected by tracking devices) and movement modeling, Derocher and colleagues have investigated how well grizzlies remember where food is and when it is best to visit a foraging patch. Derocher's research showed that about two-thirds of the bears have a great memory for where and in what season they previously found food. His tracking data also revealed that wild bears generally avoid humans. But bears have only a few months to fatten up for winter. If food is scarce, many bears go into human environments and sometimes get killed, Proctor said.

The data is also offering insight into different bear "personalities." Bears are ultimately individuals, with their own traits and quirks, Servheen said.

Tracking data suggests that a lot of bear behavior is transmitted culturally via a mother's influence. Sometimes, the wrong behavior can get passed down to the next generation, Servheen said. For example, an infamous female grizzly known as 399 jaywalked potentially hundreds of times in the Jackson Hole valley in Wyoming while managing to keep her distance from humans. Her 20-odd cubs learned to follow her example, but they lacked her strategic caution. Several were killed by vehicles or management euthanizations.

"It's a risky thing to teach your kids to do stuff like that," Servheen said. "And her offspring weren't as smart as she was."

A cracked windshield

Further north along the region between Yellowstone and the Yukon, Proctor's first DNA survey across 1,500 square miles (4,000 square kilometers) of southern British Columbia in the late 1990s shattered his illusion that the bears, along with bighorn sheep (Ovis canadensis) and other species in this province, were free to roam. Instead, he found a "cracked windshield" landscape, where roads and human sprawl had fractured the wilderness into isolated genetic islands. In the 2000s, the genetic diversity of the South Selkirk grizzly bears — a detatched subpopulation inhabiting southeastern British Columbia, northern Idaho, and northeastern Washington — was so low, for example, that biologists feared the bears wouldn't survive.

But Proctor and his colleagues went on to use bear movement data to model pathways through human-settled valleys. Proctor was so convinced about the viability of one potential corridor that he paid 10,000 Canadian dollars ($7,000) of his own money to buy a key piece of land right in the middle of it. "That was the first canoe over the waterfall of purchasing connectivity land," Proctor said

Proctor’s land secured a segment of a crucial connectivity corridor and, in the following years, he and other scientists partnered with trusts to purchase other land parcels, build fences, and establish safe corridors for grizzlies in the Creston Valley in southeastern British Columbia. These actions helped bears move north and south (sometimes across the border) and between the South Selkirk Mountains and Purcell Mountains. The researchers then watched bears like "Captain Hook," who'd been shot in the leg, hobble into the South Selkirks and breed with eight females. By 2021, nine immigrant bears had produced 27 new offspring within the population.

"This is gene flow; this is connectivity," Proctor said. "We took a completely isolated population and pretty much recovered it."

Despite efforts to safeguard corridors through human occupied landscape, roads continue to stop bears in their tracks. When Servheen tracked bears near Highway 2 in northwest Montana, he found that many of the grizzlies avoided the highway altogether and those that crossed did so at night. But he also found that the bears' crossings clustered in specific sections of the road. Finding the crossing zones has helped researchers identify good locations for constructing overpasses and underpasses on many busy highways, but a crossing structure on its own is not enough, Servheen cautioned.

A bear's memory for where to find food is exemplary, but there's no special reward in a bear's brain for crossing a road safely — only a fatal penalty when they don't, Servheen said. So conservationists can't rely on bears to remember where crossings are. Instead, they must build fencing along the highway to funnel wildlife into the underpasses or overpasses. Then, the immediate land on each side needs to allow animals safe passage. "Otherwise, you have a bridge to nowhere," Servheen said.

Now researchers such as Sells are trying to use data about bears' likeliest routes to determine potential corridors in locations where they have little tracking data or where few bears live yet.

To do this, Sells is developing a virtual "Sims for Bears" that recreates the Continental Divide Ecosystem in Montana. In the life-simulation video game "The Sims," players give virtual humans personality traits, preferences and needs, and then drop them into a virtual environment to see how they behave.

Sells built the model using the GPS collaring data from 65 grizzly bears navigating individual paths through greenery, riparian areas and around forests and roads. Then, she "parachutes" an individual digital bear into a detailed computer simulation of real-world terrain and has them take thousands of virtual steps. By running these multiple simulated bears through thousands of iterations across the digital terrain, the researchers can watch where the virtual bears repeatedly choose to walk, effectively creating a map of predicted movement corridors.

Sells has used the model to predict how grizzly bears might recolonize the Bitterroot ecosystem of Idaho and Montana, which Lingenpolter was heading toward when attempting to cross Interstate 90.

To get to the Bitterroot Mountains, bears must pass through a valley filled with people, roads, garbage and fruit trees. "So knowing where they are more likely to end up is helpful to address things that could be difficult for humans or bears," Sells told Live Science.

The people problem

The data is also confirming that the greatest barrier bears face comes from human contact or transportation infrastructure across the entire Yellowstone-to-Yukon region. Studies from across west-central North America report that humans directly or indirectly caused between 77% and 90% of grizzly bear deaths from 1989 to 2015. Hunting, managed kills in urban areas and road and rail collisions all take a toll.

Bears in the wild usually avoid people, but some bears seek out human-dominated areas because they know these places are a source of food. People move to the Elk Valley in southeastern British Columbia because they love nature, but then they plant apple trees in their backyard, which attract bears, said Clayton Lamb, a wildlife scientist at the nonprofit Biodiversity Pathways.

Quickly, a bear eating backyard apples gets labeled a "problem bear," "when really it is a 'people problem,'" Lamb told Live Science.

Even human recreation takes a toll on bears' health and ability to move freely. Lamb's research has shown that grizzly bears try to avoid areas next to busy cycling and hiking trails.

To minimize human-bear conflict, Michelle McLellan, a wildlife ecologist at Biodiversity Pathways, has tracked trail use by both people and grizzlies in the West Kootenay region of British Columbia. McLellan documented people's habits using trail cameras and apps such as Strava Metro. Her research shows that the bears use the trails to move quickly between foraging spots but have learned not to use the trails that are most popular with humans. Consequently, the Nelson Cycling Club decided to close certain trails in the spring and cautioned riders about when and how to use the open trails. "Ride aware, make noise, slow down when needed," the club cautioned in its May newsletter.

Working with information from McLellan, the club has cut back overgrown vegetation along sight lines to prevent mountain bikers from startling bears at close range. They've also constructed wooden platforms on sections of trails that clatter and rumble as bikes pass over them, giving bears early notice of approaching riders. "The key is to not surprise them by making a lot of noise." McLellan told Live Science, noting that grizzlies are more likely to attack if they are surprised.

One advantage of having human mountain biking and hiking trails concentrated close to towns is that it focuses recreation into specific areas, Lamb said. Keeping trails condensed supplies multiple accessible paths and reduces humans encroaching on true wilderness — prime bear habitat. "The goal would be to ensure that there's sufficient recreation opportunities for people to stay healthy and connected to their local landscape while ensuring that wildlife can still move around and access their habitats," Lamb said

Learning to share

As humans increasingly live, work and play in bear territory, it's important to recognize the impact on the animals, Servheen said. "The bears never get a day off," he said. "Every day, they're trying to stay away from people and make a living in a place with multiple people on the landscape."

Bears expend a lot of much-needed energy trying to avoid people, and they won't be able to do that forever, Servheen said. As humans increase the development of private lands and recreation in bear territory, the squeeze is on. "There's going to be more conflicts with bears, and more dead bears," Servheen said.

The bears have done their part, Lamb said. His research has shown that bears living near humans are adapting by becoming mostly nocturnal, which reduces their odds of clashing with humans. "So, we need to meet them where they are at and see what we can do to share the space," Lamb said.

On the human side, people need to make it less tempting for bears to be in human dominated areas, McLellan said. That means keeping garbage stowed and making sure there is no ripe fruit available. "If you live rurally, you want them to be able to pass through your property but not linger near your home or in your front yard," McLellan said.

Bears have proved to be adaptable and persistent; Lingenpolter tried to cross the highway dozens of times before finding a way under. However, Servheen warned that we are putting them in a tough spot. To keep bear populations stable, scientists need data on bear behavior to help inform land management policies that create safe pathways for grizzlies to move through human dominated areas and regulate recreation with bears in mind, Servheen said.

"If we want to have bears in the future, we need to think about the needs bears have for some level of space on the landscape," Servheen said.

Securing that space across the vast Yellowstone to Yukon landscape requires more than just land acquisitions and highway overpasses — it requires increasing public awareness and counteracting the perception that bears are inherently aggressive and irrational, Proctor said. If people understand bear behavior, they can learn to act in ways that neither attract bears nor threaten them. And understanding the totality of bears’ strong drive to survive, and protect each other, can elicit empathy and motivation to protect this iconic species.

Early in his career, Proctor captured, immobilized and radio-collared a mother grizzly with her two yearlings, or newly adolescent bears. While the research team worked, the young bears circled quietly at a distance. When the scientists finally stepped back and the mother began to stir, the yearlings approached cautiously. As the mother's groggy head rested on a log, the yearlings' long-clawed front paws delicately explored the radio collar. Then, each one rested its head directly on hers, to form a quiet pile of three bear heads.

"They just wanted to touch mom after this ordeal," Proctor said. "Yes, grizzlies can be rough and dangerous but they can also be gentle at times," Proctor said.

Reporting and travel for this story was supported by the Sitka Foundation and the Science Media Centre of Canada.

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Every year, the Royal Meteorological Society's Weather Photographer of the Year competition offers a reminder that some of the world's most compelling images emerge from the unpredictable forces of nature. The 2026 short list includes 30 photographs selected from more than 5,500 entries submitted by photographers around the world. Each offers a different perspective into the relationship among weather, landscapes and the people who experience these natural phenomena.

The short-listed images span a range of settings and subjects, from lightning strikes, to cloud swirls, to rainbows. You can explore the full short list and vote for your favorite photo before the competition ends on Thursday (Nov. 5).

Live Science rounded up seven images that stood out for their composition, atmosphere and ability to tell a story. Which one is your favorite? Let us know in the comments!

"Mount ShastaTop Hatat Sunset"

Photographer Lisa K. Kuhn captured a lenticular cloud above Mount Shasta in California.

"Triple strike NYC"

Watching from Bayonne, New Jersey, photographer Dan Martland captured this triple lightning strike above New York City.

"A Supercell in the Sandhills of Nebraska"

"Mother Nature was kind enough to give us a supercell and lightning at night," said photographer Laura Hedien about seeing this storm in Nebraska.

"Lakeland Rainbow"

During a walk in England's Lake District, photographer Mat Robinson waited in the pouring rain and eventually took this image of a beautiful rainbow.

"Ice Hearts"

While walking through a wintery landscape in Bachledova dolina, Slovakia, photographer Dominika Koszowska noticed ice forming on wire mesh, creating unique heart shapes.

"Fire"

Photographer Erfan Samanfar snapped a haunting image of a farmer trying to protect his farmland from a raging fire in Marvdasht, Iran.

"Castles in the Wind"

Photographer Andres Miraglia captured the moment a floating iceberg was seen in the sunset off of Antarctica's Paradise Harbour.

A peanut allergy diagnosis in infancy can mean years of avoiding the food or undergoing treatments to build tolerance. But a recent study suggests that more than one-third of babies thought to have the allergy may stop reacting badly to peanuts within months of that diagnosis.

In an analysis published in The Journal of Allergy and Clinical Immunology: In Practice, researchers conducted supervised "food challenges" with infants diagnosed with a peanut allergy. These challenges involved giving the babies increasing amounts of peanut protein, with the intention of confirming whether they indeed had an allergy.

The team found that more than 1 in 3 infants who underwent the food challenge tolerated the peanut protein, meaning they didn't experience symptoms of an allergic reaction.

"This rate is much higher than we thought," study co-author Dr. Timothy Brettig, a pediatric allergist at the National Allergy Centre of Excellence in Australia, told Live Science.

Between April 2024 and October 2025, Brettig and colleagues retroactively reviewed the medical records of 1,275 infants who had been referred to Australian public hospitals after having a reaction to peanuts before their first birthday. These babies had first been assessed by allergy specialists at a median of 10 months of age.

For their initial diagnosis, the babies had to have a history of an allergic reaction to peanuts and show evidence of peanut sensitization on an allergy test. These tests included a skin-prick test, in which peanut extract is placed on the skin before it's lightly pricked, to check for a local reaction; and blood tests that detect antibodies against peanut proteins.

"Children under 1 year of age are an interesting group, as their immune system is still in rapid development and existing allergy tests may not reflect their allergic status well," said Dr. Alexandra Santos, a professor of pediatric allergy at King's College London who was not involved in the study. While these tests can hint that a child is sensitized to certain foods, they don't necessarily confirm that a baby will have an allergic reaction upon eating said food; the tests can also give false positives.

Of the 1,275 infants, 778 later underwent a food challenge roughly six months after their first recorded allergic reaction; at that point, their median age was 13 months old. They were given up to seven gradually increasing doses of peanut protein, ranging from 15 to 1,300 milligrams. These doses were given at 15-minute intervals while medical staff monitored the children for signs of an allergic reaction.

Nearly 35% of the participants — 271 kids — completed the challenge without reacting.

"This is an excellent article," said Dr. Drew Bird, a pediatric allergist at the University of Texas Southwestern Medical Center who was not involved in the study. "The take-home message is to strongly consider a supervised oral food challenge when an infant's peanut allergy diagnosis is uncertain."

Bird emphasized that these challenges should ideally be done before a child starts oral immunotherapy, a treatment in which patients regularly consume carefully measured amounts of the food they are allergic to. The dose is gradually increased under medical supervision, with the goal of helping the patient tolerate greater amounts of the allergen and reducing the risk of reactions from accidental exposure.

The starting dose is often determined through a similar oral food challenge to the one used in this study, though. So in theory, that challenge would help reveal whether the child needs treatment in the first place.

Bird cautioned that food challenges should be performed by a board-certified allergist-immunologist and an experienced allergy team in a setting equipped to treat anaphylaxis — a severe, potentially life-threatening allergic reaction.

In this study, 507 infants reacted during the food challenge, and of those, 61 developed anaphylaxis and were treated with epinephrine (the hormone in EpiPens).

"In an ideal world, with infinite resources," Santos said, "all patients except for those with a history of severe reactions would have a food challenge for diagnosis."

Because that is not the case, the families of infants whose allergy diagnosis is uncertain may be advised to avoid peanut products while they await a formal food challenge, she noted. But in the interim, they may miss an opportunity to help the child develop tolerance and, in turn, increase the risk that their allergy will persist.

Food challenges should be prioritized for infants whose allergy diagnoses are uncertain, she said. This would include babies who have low levels of peanut-specific antibodies in their blood or who show only small welts on skin-prick tests.

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

A particle-detecting telescope sunk more than a mile beneath the sea off the coast of France has tested a core principle of Einstein's relativity and found no cracks.

The detector, called Oscillation Research with Cosmics in the Abyss (ORCA), detects elusive particles called neutrinos. As a doctoral student, Alba Domi rode onto the Mediterranean aboard one of two boats that helped build the telescope, lowering some of its first detection units to the seafloor about 1.5 miles (2.4 kilometers) below the waves off Toulon, France.

Now, data from those first detection units have been used to test one of the founding rules of Einstein’s relativity: the idea that the laws of nature look the same no matter which way you face or how fast you move.

The team found no sign that this rule, called Lorentz invariance, is broken. But even with a detector only a fraction of its planned size, they set limits that compete with those of far larger and longer-running experiments.

The results were published Wednesday (Nov. 4) in the Journal of Cosmology and Astroparticle Physics.

A crack in space-time?

Physics rests on two successful theories: general relativity, conceived by Albert Einstein more than 100 years ago, and the Standard Model of subatomic physics.

"General relativity describes the universe well on a cosmic scale, and the Standard Model of particle physics describes the microscopic scale; really, the single particles, how they behave," said study co-author Lukas Hennig, a doctoral student in advanced physics at Erlangen-Nürnberg.

Both theories assume Lorentz invariance to be true. But in extreme settings, such as the first moments after the Big Bang, the two theories don't mesh. That has fueled a decades-long hunt for a theory of quantum gravity that unites them. Some candidates, including versions of string theory and loop quantum gravity, suggest that space-time might have a hidden "grain" at the tiniest scales — and that Lorentz invariance, "one of the most basic assumptions we make about our universe, might be violated," Hennig said.

Any such violation would be extremely small. To spot it, physicists would need a probe that could travel long distances and barely interact with anything along the way. Enter the neutrino.

Shape-shifting ghosts

Neutrinos are nearly massless particles that pass through Earth every second and carry zero charge. They barely interact with anything and come in three types: electron, muon and tau neutrinos. As neutrinos travel, they morph from one type into another in a predictable pattern that physicists call neutrino oscillation.

If Lorentz invariance were broken, that oscillation would change, with the effect growing more pronounced the farther the neutrinos traveled. So the team focused on neutrinos created when cosmic rays slam into the atmosphere elsewhere on the globe before traveling up through the planet to the detector. Some of the tested neutrinos crossed the entire 7,900-mile (12,700 km) width of Earth.

ORCA is part of the KM3NeT neutrino telescope. Each of its detection units is anchored to the seabed and holds 18 glass spheres packed with 31 light sensors apiece. When a neutrino collides with a particle in the water, it produces a faint flash of blue light that the sensors catch. The many sensors in each sphere help the team pin down which direction the light came from, Domi said.

Earth itself serves as a filter. The researchers selected only particles traveling upward through the planet, and they were able to weed out the flood of other particles from the atmosphere that would otherwise swamp the signal. "Only the neutrinos can get through," Hennig said.

That setup differs from that of IceCube, the Nobel Prize-winning detector buried in Antarctic ice. "Ice scatters the light more than water, but on the other hand, water absorbs the light more than ice," Domi said, which changes how each team reconstructs a neutrino's energy and path.

Small but mighty

The researchers used 5,828 neutrinos collected over about 17 months between 2020 and 2021. They found that the oscillations matched standard physics. That means if Lorentz violation exists, it must be weaker than the limits the team set.

Those limits matter for theorists. If a model "predicts a Lorentz invariance violation [stronger than the new limits], the data rule it out. In that case, you can be pretty sure that this model is not correct," Hennig said.

The team also set the first direct limits on a kind of violation that would treat muon neutrinos and tau neutrinos differently.

The detector's limits on several key measures are competitive with those from Japan's Super-Kamiokande, which used 12 years of data, and from IceCube, which used two years of data from its full array.

"I'm surprised that we have competitive results with only six detection units," Hennig said. Today, 44 units are in the water, and the collaboration plans to activate 108 by 2030.

The best tests may still lie ahead. Because Lorentz-violating effects grow with distance and energy, neutrinos from distant cosmic sources are "actually the best candidates to do this kind of research," Domi said. The team plans to repeat the search using ORCA's sister detector, ARCA (Astroparticle Research with Cosmics in the Abyss), which sits off the coast of Sicily and is designed to catch those high-energy cosmic travelers.

If space-time does have a grain, those particles may be among the first to feel it.

See how much you know about Albert Einstein with our Albert Einstein quiz!

Southeast Asia's tropical forests owe their rich biodiversity to a tiny fragment of Earth's crust that split from what is now northwestern Australia roughly 150 million years ago, a new study reports.

The fragment transported hundreds of flowering species and a flourishing collection of other ancient plants north across the prehistoric Tethys Ocean, the research reveals. The findings contradict previous theories that the fragment originated closer to what is now Southeast Asia and that Southeast Asia's tropical forests evolved sometime after the extinction of the dinosaurs around 66 million years ago.

At the time the fragment formed, Australia was connected to Antarctica and India within the ancient supercontinent Gondwana, which the Tethys Ocean separated from another ancient supercontinent, called Laurasia.

After drifting northward for 100 million years, the microplate eventually collided with Southeast Asia, seeding tropical forests that evolved into the lush ecosystems found in this part of the world today, the researchers said.

"The rich tropical rainforest flora of [Southeast Asia] is not endemic but owes much of its biota to the great southern land, Gondwana," study co-author Byron Lamont, a distinguished professor emeritus in Curtin University's School of Molecular and Life Sciences in Australia, told Live Science in an email.

But the collision with Southeast Asia was far from smooth, Lamont said. The fragment, which is known as the West Burma Block (WBB) or the Burma terrane due to its location in western Myanmar, wasn't the only piece of crust crossing the Tethys Ocean around 100 million years ago. The Indian subcontinent was also moving north, and it was doing so at a relatively rapid speed of 4 inches (10 centimeters) per year.

Around 80 million years ago, the Indian Plate bumped into the WBB, altering the fragment's orientation. The Indian Plate continued to shove the WBB until they both collided with Asia. The Indian Plate then slid beneath the Eurasian Plate to form the Himalayas, and the WBB ground to a halt to the west of present-day Myanmar, where it created a deep valley between mountain ranges about 35 million years ago, Lamont explained.

Both the Indian Plate and the WBB "took some time to stop," he said.

From the time the WBB broke off from Gondwana until its collision with Southeast Asia starting 50 million years ago, the microplate spent tens of millions of years hovering near the equator, where it was humid and hot like it is today. This climate and the fragment's isolation provided a refuge where ancient plant lineages could survive and diversify, Lamont said.

For the study, Lamont and his colleagues examined more than 3,000 plant fossils from Myanmar that were preserved in amber around 100 million years ago. The fossils included flowers, leaves, fruits and seeds. They belonged to at least 392 types of flowering plants and a vast array of conifers, ferns, mosses, cycads and liverworts that reached Southeast Asia by floating on the WBB.

Amber has been mined from the north end of the WBB valley for at least a century, Lamont said. "Its beautiful fossils, preserved in 3D, have long attracted interest for their novelty value alone and there has been much commercial interest in them, especially from Chinese traders," he noted.

Some of the study's co-authors acquired chunks of amber from traders at least a decade ago, and they have been studying these pieces ever since. Advice was often required from experts at other institutions around the world, which is how Lamont got involved in the study, he said.

The findings, published Oct. 27 in the journal Nature Ecology & Evolution, reveal the deep evolutionary roots of the tropical forests that grow in Southeast Asia today. The WBB didn't strip Australia of its ancient flora, because the descendants of many plants found in the 100 million-year-old amber still exist in the country's Northeast, which is hot and humid, Lamont said.

It's hard to say what kinds of animals arrived in Southeast Asia via the WBB, because only creatures small enough to be preserved in amber are represented in this fossil assemblage.

"The animals present in the amber are small insects, such as ants and mosquitoes," Lamont said. "Typical Australian vertebrates, such as marsupials, emus and nectar-feeding birds, arrived from South America in Australia over 100 million years later [after the WBB split off], and of course they would not have got caught in the resin even if they had been around."

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

It's the end of an era: NASA's Swift telescope has reached the conclusion of its nearly 22-year mission, burning up in Earth's atmosphere after studying some of the universe's most powerful and mysterious events.

According to NASA, the spacecraft reentered the atmosphere at "7:39 a.m. EST Wednesday over the North Sumatra region of Indonesia, at approximately 3.4 degrees north latitude and 98.6 degrees east longitude." NASA expected most of the telescope's structure to burn up during its passage through Earth's atmosphere, estimating a 1-in-2,100 chance of any surviving debris falling over a populated area. No damage or injuries have been reported.

Weighing approximately 3,200 pounds (1,450 kilograms), the Neil Gehrels Swift Observatory was initially designed for a two-year mission, but it far exceeded expectations. Over two decades, Swift became an important tool in the study of gamma-ray bursts, supernovas, black holes and other cosmic phenomena.

Exceeding expectations

Launched in November 2004, Swift was designed to detect gamma-ray bursts, powerful explosions that occur throughout the universe. Its three onboard telescopes let scientists observe cosmic events across different wavelengths, including ultraviolet, optical and X-ray light. The telescope could swivel to focus on different sky targets in a matter of minutes, allowing it to rapidly follow up on sudden events like supernova explosions.

NASA estimates that Swift's scientific observations have contributed to approximately 7,000 research papers, leaving behind an extensive collection that scientists can continue studying for years.

Why did Swift's mission end?

Swift's return was driven by atmospheric drag, which eventually slowed the spacecraft and caused its orbit to decay. Increased solar activity intensified the drag, thus accelerating the space telescope's descent toward Earth.

Earlier this year, NASA explored an ambitious rescue mission to extend Swift's operational life. In August 2026, a privately developed robotic spacecraft built by Katalyst Space Technologies was intended to rendezvous with Swift and boost it into a higher orbit. However, the mission failed after launching, leaving the observatory on its path toward reentry.

NASA officially ended Swift's scientific operations on Oct. 20 after its declining altitude made observations too difficult. For NASA and the broader astronomy community, Swift's story is a reminder that even missions designed to last just a few years can fundamentally change our understanding of our universe.

Archaeologists in Ukraine have found a colorful belt buckle that may have been worn by a nomadic equestrian warrior 1,800 years ago on the fringes of the Roman Empire.

The belt buckle was unearthed by local residents in the Tsetsyn Forest in southeastern Ukraine and given to Antonii Moisei, a professor at Bukovinian State Medical University, according to a translated statement. The roughly square metal buckle, which is about 0.8 inches (2.1 centimeters) on each side, has teal, blue and yellow enamel decorations.

The style of the decoration and the metal construction place the creation of the buckle in the second to third centuries A.D., when this part of Ukraine was in the ancient province of Roman Dacia, according to Moisei.

Under Emperor Trajan, Rome fought the Dacian Wars (A.D. 101-102 and 105-106) against the denizens of the Dacian kingdom and its leader, Decebalus. Roman legions destroyed Dacia and annexed it as a new province. Trajan celebrated his victory in Rome, complete with a famous column that depicts details of the Dacian Wars.

In addition to the buckle, Moisei collected a decorative belt fitting and three small, round metal objects that probably belonged to the same belt. Moisei created a reconstruction of what the belt might have looked like before it was lost in the forest nearly two millennia ago.

But it's unclear who lost the belt. One of Moisei's theories is that the belt belonged to a horse-riding Sarmatian warrior originally from the Black Sea region. The Sarmatians were a group of tribes that lived outside the borders of the Roman Empire, in what are now central Ukraine, southern Russia and the Balkans. While some Sarmatian warriors fought against the incursion of the Roman Empire, others fought with Rome as mercenaries.

The metal belt fragments are part of a Roman provincial craft tradition, according to the statement, and they may have been obtained through trade or as a trophy of war. But Moisei is still studying the artifacts to confirm whether they were Sarmatian. Either way, the military belt provides new evidence of Roman military contact on the outskirts of the empire, and future work could help experts understand how the Romans interacted with the local Dacians during wartime.

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

A noxious gas found seeping through cracks on Mars hints that there may be magma flowing beneath the Red Planet's surface — and perhaps even an environment similar to habitable ones on Earth, a new study suggests.

Europe's ExoMars Trace Gas Orbiter (TGO) spacecraft spotted a possible signal of hydrogen chloride gas leaking from rifts in the region of Alba Mons, the largest volcano on Mars in terms of surface area. (Mars' famous Olympus Mons is the largest volcano in terms of height.) Scientists interpret this gas as emissions from hot magma below the regolith of Mars.

Although more research is required to confirm the emissions, the team suggested that Alba Mons may host an environment similar to hydrothermal vents on Earth, where life once likely arose and continues to thrive today.

The study, published in the journal Science Advances Wednesday (Nov. 4), is not the first to suggest that magma may be flowing on Mars; NASA's InSight lander interpreted its presence through seismic observations and modeling earlier this year. But the new findings are the strongest evidence yet of gases being released by dormant volcanoes on Mars, first study author Alexander Trokhimovskiy, at Russia's Space Research Institute, told Live Science.

"Our study offers a complementary and potentially independent line of evidence [of Martian magma]: Atmospheric observations that reveal a possible signature of gas release from a subsurface magmatic system," Trokhimovskiy wrote in an email.

Europe smelt it — but what dealt it?

TGO first detected hydrogen chloride gas in Mars' atmosphere in 2021, but scientists were hesitant to link it to volcanic activity. The gas appeared to be seasonal, its distribution was not localized at a possible volcanic region, and other signs of volcanic gases, like sulfur, were not present, study co-author Kevin Olsen, a visiting researcher at the University of Oxford who studies Mars gases, told Live Science in a separate email.

Further work, however, suggested that the gas wasn't just popping up in the warmer spring and summer in Mars' southern hemisphere; it also appeared in the winter in the northern hemisphere, he noted.

"I managed to catch two observations from the start of northern winter in the first Mars year of our mission, and a single observation the next year," Olsen said, adding that a year on Mars is closer to two years on Earth due to the planet's wider orbit. "These out-of-season measurements were close to one another in location and time in both years, which was rather surprising. We then set about creating a campaign of special, targeted measurements at this time and place."

That campaign lasted two Mars years — roughly four Earth years — and increased the likelihood that scientists are seeing "an injection" of hydrogen chloride into the atmosphere from volcano-adjacent vents, Olsen said.

The scientists confirmed the unseasonal observations in the northern hemisphere, finding a "distinct and pronounced signal" that then diminishes and falls below the spacecraft's detection threshold. "This inconsistency is more suggestive of a puff of gas entering the atmosphere than of regular atmospheric chemistry," he said. "While the link remains a hypothesis, we have now seen this gas appear locally, and nowhere else, over four Mars years of observations."

Daniel Mège, also a co-author of the paper and a professor who studies planetary geology at the Polish Academy of Sciences, identified the fissures where the gas may be emerging. He said the complementary evidence from InSight (on the ground) and TGO (circling above) helps give the study weight: InSight spotted activity in the crust, while TGO detected the emissions in the atmosphere.

Although magma activity is not in itself a sign of life, Mège noted that Earth's first life-forms came from sites like hydrothermal zones, which have a similar confluence of materials and energy as the potential vents on Mars. But conditions would need to be favorable in that area for at least millions of years to allow life to form, he cautioned.

"If these requirements are met at local scale, at the scale of the seepage structures, then living organisms might wait for us to discover them," he told Live Science in an email. "But maintaining stable conditions over such a long period at a very local scale is not obvious."

What do you know about the Red Planet? Test your knowledge with our Mars quiz!

A toothbrush that generates its own electricity with every stroke could offer a new way to fight the microbes behind cavities and gum disease.

Conventional toothbrushes rely on physical scrubbing to remove plaque from teeth and gums. But even after a thorough brush, some bacteria remain and begin rebuilding plaque. To solve that problem, researchers have developed a self-powered toothbrush that converts the friction of brushing into an electrical charge. That electricity is intended to zap the plaque-promoting bacteria and keep them from colonizing teeth.

"It's great to have new approaches that actually enhance the effect of mechanical cleaning," said Nicholas Jakubovics, an oral microbiologist at Newcastle University in the U.K. who was not involved in the study. "The idea that the toothbrush surface itself is actively doing something is really interesting."

The experimental brush has bristles made from polyvinylidene fluoride (PVDF), a plastic that generates electricity when bent; these types of energy-producing materials are called piezoelectric. As the bristles flex during brushing, they produce an electrical charge that then triggers chemical reactions in saliva and water. These reactions release reactive oxygen species (ROS), which are highly reactive molecules that can damage bacterial cells.

Even when the bristles are not being used to brush, they carry a faint surface charge that helps prevent bacteria from clinging to the brush head when the toothbrush isn't in use, the team reported Wednesday (Nov. 4) in the journal Science Advances.

In laboratory tests where the toothbrush was used on isolated germs, its electrified bristles killed more than half of the Streptococcus mutans bacteria present. These microbes contribute to tooth decay. By comparison, nylon bristles killed just 9% of the bacteria. They also reduced levels of Porphyromonas gingivalis, a bacterium linked to gum disease, by up to 78%, while nylon brushes reduced them by less than 8%.

When the researchers added an antioxidant — a compound that neutralizes ROS — the new toothbrush's antibacterial effect largely disappeared, highlighting that the ROS are likely the key to its effects.

The team also found that the activity of certain genes in both S. mutans and P. gingivalis fell after exposure to the electrified bristles. These genes are involved in making ATP-binding cassette (ABC) transporters — molecular pumps that help shuttle essential nutrients across bacterial cell membranes. The researchers suspect that disrupting this machinery makes it harder for these microbes to survive and cling to teeth.

But Jakubovics was not convinced by that part of the team's explanation. "ABC transporters transport all sorts of different things," he said, adding that the findings did not clearly show how changes in these genes affected the bacteria.

The researchers also tested the new brush against plaque biofilms — hardy communities of bacteria that stick together and cling to tooth surfaces. For the experiment, they grew human dental plaque on cow tooth enamel and found that the brush removed more than 99% of the biofilm, outperforming a regular nylon brush.

Finally, the team moved to humans, putting the brush to the test in 115 adults with gum inflammation or tooth decay. These study participants were randomly assigned to use either the new toothbrushes or traditional nylon-bristled brushes twice a day for three months. (The study didn't note whether participants noticed a difference in sensation when using the electrified brushes.)

By the end of the trial, the participants who used the electrified bristles had less plaque, less gum inflammation and less bleeding than the participants who used ordinary brushes. Plaque samples also showed that the people who used electrified brushes had lower levels of bacteria associated with oral disease and higher levels of beneficial bacteria, which have previously been reported to suppress harmful oral bacteria and support oral health.

The researchers think that the disease-linked bacteria may have relatively fragile cell membranes, making them more vulnerable to damage from ROS than the beneficial bacteria. That's a theory that requires further study, though, so it's not completely clear how selective the brush is against plaque-causing bacteria.

In a test of the toothbrush's durability, the PVDF bristles retained their structure and electrical properties over three months of simulated use. Lab-grown mouse cells repeatedly exposed to brush material showed no signs of damage, and brushing on cow tooth enamel did not increase surface roughness. However, these tests cannot establish whether repeated use of these brushes is safe for humans.

"We would want to make sure that it is safe on the tissues for long-term use," Jakubovics said. He noted that, in lab tests, bacteria are grown directly on the bristles and exposed to their electricity for hours, "whereas in reality, in the mouth, your bristle is only in contact with the tooth or oral tissue for a very short time."

The trial with humans provides some insight into how the brush works in real life, but it was relatively small. Larger studies will be needed to find out whether the toothbrush offers a meaningful advantage over conventional brushes. For now, Jakubovics sees the recent study as just a proof of concept; more information and more convincing clinical data are still needed, he emphasized.

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

One of autumn's best opportunities to see brilliant "fireballs" arrives overnight Wednesday and Thursday (Nov. 4-5) during the Southern Taurid meteor shower.

Although the Southern Taurids are a minor meteor shower that produces only a handful of "shooting stars" each hour, it occasionally features exceptionally bright meteors called fireballs, which can briefly light up the night sky. According to NASA, fireballs are meteors at least as bright as Venus.

The Southern Taurids are active for several weeks in fall and peak Oct. 14, but the American Meteor Society expects the "fireball swarm component" to peak around Nov. 4-5.

Meteors can streak across any part of the sky, but for this meteor shower, they appear to radiate from the constellation Taurus, which will rise in the eastern sky as night falls and climb higher as the night progresses. That makes the hours around midnight a good time to look for shooting stars. However, unlike major meteor showers such as the Perseids (which peak Aug. 12-13) and the Geminids (which peak Dec. 13-14), the Southern Taurids have a broad peak, so there's no need to be outside at an exact time.

The Southern Taurids are the first of two fireball-rich meteor showers to be visible this month. The Northern Taurids will peak overnight on Nov. 11-12, giving stargazers another chance to spot a fireball. Both meteor showers result from dust and debris left in the inner solar system by Comet 2P/Encke striking Earth's atmosphere.

Discovered in 1786, Encke is a massive comet, measuring 2.98 miles (4.8 kilometers) in diameter, according to NASA ‪—‬ around one-third the size of the object thought to have killed the nonavian dinosaurs. Encke orbits the sun every 3.3 years, one of the shortest known orbital periods of any comet in the solar system. Scientists theorize that Encke is one of many fragments of a giant comet that broke apart 20,000 to 30,000 years ago.

After the Southern and Northern Taurids, the next meteor shower will be the Leonids, which peak Nov. 17-18 and produce around 15 shooting stars per hour, and the Geminids, which peak Dec. 13-14 and can deliver up to 120 shooting stars per hour close to the peak.

It's best to watch meteor showers with the naked eye, but a good backyard telescope will serve you well in the months to come. As the long nights of winter kick off in the Northern Hemisphere, skywatching opportunities abound — including four consecutive supermoons from Nov. 2026 to Feb. 2027.

Dinosaurs are more than extraordinary specimens with massive price tags. They are irreplaceable snapshots of our planet's history and our own human journey. When scientifically important fossils are reduced to luxury commodities, we are robbed of the evidence that makes them valuable in the first place.

On Oct. 27, a 19.6-foot-long (6 meters) skeleton of Nanotyrannus lancensis known as "Jodi" was sold at Sotheby's in New York for $47,255,000, far exceeding its $6 million to $9 million estimate. The buyer and seller were not identified. It was the latest in a string of multimillion-dollar dinosaur auctions, following the $50.1 million sale of a T. rex (Gus) in July and the $44.6 million sale of a Stegosaurus (Apex) in 2024.

Fossils like Jodi, Apex, and Gus belong in public collections, where they can contribute to science and remain accessible for future generations. Not in the hands of private collectors.

There are three main reasons why. First: Fossils are evidence, not objects. A dinosaur's bones can reveal how it grew, moved, fed, and lived. They preserve traces of injury and disease, help reconstruct ancient ecosystems, and offer clues about the "rules of life" governing our world that scientists are still learning to interpret.

Jodi illustrates exactly why access to physical evidence matters. For nearly half a century, paleontologists debated whether Nanotyrannus was a distinct dinosaur or simply a juvenile T. rex. A lack of well-preserved fossils available for study only fueled the uncertainty. And then a remarkable specimen, once in private hands, moved into the public trust.

The fossil was uncovered in Montana in 2006 alongside a Triceratops. Dubbed the "Dueling Dinosaurs," it took until 2022, and an appeal in the state's Supreme Court, for the remains to be acquired by the Museum of Natural Sciences so they could be fully studied. This research provided a powerful new perspective, arguing that Nanotyrannus lancensis was a distinct dinosaur and, moreover, that a second species of Nanotyrannus once roamed the American West.

This hypothesis has big implications for the health of ecosystems before one of Earth's most severe extinction events — but it currently rests on the scant few Nanotyrannus specimens housed in public collections. Specimens like Jodi could uphold or dethrone it. Without access, we, and Jodi’s true identity, will remain in the dark.

It is hard to overstate the irony of Jodi's sale: a specimen recently listed as a juvenile T. rex now captures the world's imagination, and commands double the price tag, as a "Nanotyrannus." Yet if a similar fate had befallen the Dueling Dinosaurs and they had remained in private hands, we would not have known for certain that Nanotyrannus ever existed.

Scientific progress depends on researchers being able to compare specimens, test hypotheses, and revisit earlier conclusions. When access relies on a private owner's permission, repeatability is not assured, and science cannot proceed. A specimen might be available today but inaccessible tomorrow. This is why access to the evidence must endure.

This brings us to the second problem with privately owned dinosaurs. Digital scans cannot replace the original fossil.

Three-dimensional scans and digital models are powerful tools. We use them to measure bones, compare anatomy, share information, and educate the public. But digital models capture only the most superficial aspects of a fossil's story.

To understand dinosaur growth, we examine microscopic structures inside fossilized bone through a technique called bone histology. We also analyze the chemistry of fossils to investigate diet, migration patterns, and metabolism. Such work requires physical samples, not just images of a bone's surface. We also need contextual data about the surrounding sediments, preservation mode, and ancient environment in order to explore questions about the ecosystems in which the animals once lived. Much of this information is lost in the rush to excavate and prepare fossils as quickly as possible for the auction block. It can never be reclaimed.

We cannot predict what novel technologies future researchers will employ to make new discoveries from old bones, or even which questions they will ask. Technology will continue to advance, bringing analytical methods we cannot anticipate. A scan made today does not guarantee that researchers will have the physical evidence needed for tomorrow's discoveries. Digital access should complement preservation of original specimens, not justify losing it.

Finally, private ownership cannot guarantee lasting public access. Yes, some private collectors financially support research and education and donate specimens they purchase. Those contributions are valuable. But the issue is not whether an individual owner is generous; it is whether access is guaranteed over time.

A temporary loan is insufficient. A loaned specimen can be withdrawn, sold, or inherited by someone with different priorities, situations that are becoming increasingly common in the U.S. and abroad. By contrast, a fossil deposited in a responsible public research institution is documented, cared for, studied, and made available to future researchers and educators in perpetuity. The question is not whether people should be able to admire dinosaurs; it is whether the evidence that helps us understand them will remain available to everyone.

Nor should museums consider selling scientifically important fossils to cover operating shortfalls. Collections are not ordinary financial assets to liquidate when budgets tighten. Selling an irreplaceable specimen provides a one-time payment while sacrificing future scientific potential. Museums need sustainable funding for collections care, research, and education, not pressure to trade away the very resources they exist to preserve.

Jodi's sale is complete, but the fossil's long-term future remains uncertain. With the buyer's identity undisclosed, the public cannot know what arrangements, if any, will ensure continued access for researchers and educators. We hope the new owner will make Jodi available for scientific study and public education, through permanent placement in a public research institution. But hope is not a substitute for a guarantee.

There is a better way to support paleontology. Enthusiasts who want to share in the excitement of discovery can fund fieldwork and research, endow curatorial positions, strengthen museum collections, or donate important fossils to public institutions where we can all learn from them.

Dinosaurs inspire wonder because they connect us to a world vastly different from our own. But their importance extends far beyond their power to captivate us. They are part of our shared natural heritage and an irreplaceable record of Earth's history.

We should measure a dinosaur's worth not by the price it commands at auction, but by the knowledge it can help us build, and by whether we preserve that opportunity for generations to come. Earth's history belongs to all of us, not to the highest bidder.

Editor's note: This article was updated on Nov. 4 at 8.22 a.m. ET to correct the year the Museum of Natural Sciences acquired the Dueling Dinosaurs.

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The patient: A woman in upstate New York

The symptoms: About two weeks after her baby's birth, the woman began experiencing intensely negative emotions at every breastfeeding session. These feelings of "extreme unhappiness" would start just before her milk ejection reflex (during which milk moves from the breast ducts to the nipples) and last up to two minutes.

The feelings would end abruptly when she finished breastfeeding and then appear again the next time she was about to release milk, according to a report of the case, which the patient co-authored. The patient was a breastfeeding counselor for the United States Department of Agriculture Women, Infants, and Children (WIC) Program.

Until the baby was about 18 months old, this phenomenon would happen every time the woman breastfed — about five times per day, on average. Unlike postpartum depression,‬ which can cause persistent feelings of despondency, anxiety and mood swings in new parents,‬ the woman felt "helpless, hopeless, [and] worthless" only during her milk release. She reported that she otherwise felt happy and bonded with her new baby.

What happened next: When her baby was 7 months old, the woman began meeting with a lactation consultant, who later co-authored the case report. They worked together to track the mother's symptoms over time, noting when negative feelings began and if any intervention made them subside or worsen.

The diagnosis: Because the woman's condition did not have a formal name at the time, she began calling it "dysphoric milk ejection reflex," or D-MER.

The case report authors initially suspected that fluctuations in the woman's oxytocin levels might be causing D-MER, since the hormone is released into the bloodstream prior to the milk ejection reflex during breastfeeding. However, external factors that are known to affect oxytocin levels, such as tobacco use, did not always trigger the woman's symptoms.

Next, they looked at dopamine. The chemical messenger's fluctuations during breastfeeding are less studied than those of oxytocin and prolactin, another hormone linked to lactation. However, dopamine levels have otherwise been connected to strong emotional responses. Activities that seemed to ease the patient's D-MER symptoms — such as taking the cold medication pseudoephedrine, smoking cigarettes or binging on chocolate ice cream — are also known to increase dopamine levels. Meanwhile, acute stress, which reduces dopamine, worsened her symptoms.

The authors hypothesized that an abrupt drop in dopamine prior to milk release might be a trigger for D-MER.

The treatment: The woman began taking bupropion (better known by the brand name Wellbutrin), an antidepressant that increases the amount of dopamine in the brain. She saw a dramatic reduction in her D-MER symptoms within a day, and five days later, her symptoms were almost entirely gone.

However, she stopped taking the drug after a few weeks due to unwanted side effects (which aren't described in the report), and the symptoms came back. She then tried an herbal remedy containing roseroot (Rhodiola rosea), a plant historically used in some places to manage depression. Some recent studies suggest that compounds in R. rosea interact with receptors for chemical messengers in the brain; however, there is little reliable evidence demonstrating its purported therapeutic benefits, according to the National Center for Complementary and Integrative Health.

She took R. rosea three to four times per day, reporting that her symptoms became "much milder" but returned if she skipped a day. As her daughter grew older and the woman breastfed less often, the woman stopped taking the supplement. When the child was 3 years old and no longer breastfeeding, the woman's D-MER symptoms went away entirely.

What makes the case unique: Prior to this report, published in 2011, D-MER was not widely recognized or documented in the scientific literature, and there was no research into its causes or treatment.

The patient and co-author of the report created the website D-MER.org in 2007 to share information about the condition more widely. She hoped to raise awareness among medical professionals and to help breastfeeding people who experience this condition by providing resources and support and encouraging them to understand that what they were feeling was a physiological side effect of nursing. Since the site's launch, hundreds of visitors have described having negative feelings while breastfeeding, according to the report.

Over the past two decades, more case reports describing the condition have been published. In a 2025 paper in the European Journal of Obstetrics & Gynecology and Reproductive Biology, researchers estimated that roughly 14.2% of lactating parents experience D-MER and that 1 in 6 stop breastfeeding as a result. Dopamine is thought to play a part, but the exact cause of D-MER has not been definitively established in peer-reviewed research yet.

There is no definitive treatment for D-MER, although some have anecdotally found relief through techniques for stress reduction, such as meditation and breathing exercises, and by seeking support from partners, friends and breastfeeding groups online.

Short-lived negative feelings resembling D-MER have also been reported in people who are not lactating. These anecdotal accounts describe intense, negative feelings brought on by nipple stimulation. One online discussion group referred to this phenomenon as "sad nipple syndrome," according to the authors of the case report. As with D-MER, dopamine may play a part, but the overall neurochemistry underlying that emotional response is unknown.

Breastfeeding and parenthood can be an emotional roller coaster even under the best circumstances, the authors noted. In that sense, they explained, people with D-MER have "the same emotional peaks and valleys" as all new parents do. Yet the negative feelings that accompany D-MER are nonetheless different from the normal range of emotions in the parents of newborns, and they can cause extreme distress if they are not correctly identified and addressed as being specific to breastfeeding.

People with D-MER, the authors concluded, "serve as a reminder to us all that we do not yet have a complete understanding of human lactation."

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!

A crewed mission to Mars could be one of humanity's greatest achievements, but getting there may come with serious health risks. Beyond the challenges of surviving in space for months at a time, astronauts would face prolonged exposure to cosmic radiation ‪—‬ high-energy particles in space that can penetrate the human body and potentially damage vital organs.

A new study suggested that cosmic radiation could pose a particular threat to heart health. Researchers found evidence that rats that were exposed to radiation similar to what human astronauts might encounter during a mission to Mars and back developed more scar tissue around the small vessels in their hearts compared with rats that weren't exposed to space radiation.

Although the findings haven't been confirmed in humans yet, they add to the growing concerns about the long-term health effects of sending astronauts on long-duration space missions.

NASA and other space agencies are working on ways to eventually send humans to Mars and beyond. Given these latest findings, would you travel to Mars? Vote in the poll below, and let us know your thoughts in the comments.

Editor's note: As of 11:15 a.m. EST on Wednesday (Nov. 4), NASA and the Aerospace Corporation both predict that the Swift observatory could have reentered Earth's atmosphere by now. However, no new details on reentry have been provided. Stay tuned for more updates about where and when the telescope will fall.

NASA's decades-old Neil Gehrels Swift Observatory is rapidly falling out of orbit and could tumble back to Earth any moment now, the space agency says.

According to NASA's latest estimates, shared Monday (Nov. 2), the roughly 3,200-pound (1,450 kilograms) spacecraft was likely to reenter Earth's atmosphere around 3:30 a.m. EST Wednesday (Nov. 4), with an uncertainty of plus or minus 11 hours — meaning the defunct observatory could have plunged down as early as Tuesday evening, and as late as Wednesday afternoon.

An independent analysis from the private nonprofit Aerospace Corporation, which tracks thousands of objects in orbit, similarly estimates that the telescope should have reentered the atmosphere at 6:56 a.m. EST Wednesday, give or take three hours. Both estimates suggest the Swift spacecraft could have already met its demise as of Wednesday morning, though no official confirmation has been shared.

As with all spacecraft reentries, the risk to humans is minimal. Most of the Swift telescope is expected to burn up in the atmosphere, according to NASA. Any surviving fragments will likely fall somewhere between 20.6 degrees south latitude and 20.6 degrees north latitude — a range that includes parts of Mexico, the Caribbean, Central and South America, the Arabian Peninsula, India, Africa and Oceania, but also a lot of ocean.

NASA predicts that the chances of Swift debris falling over a populated area are approximately 1 in 2,100. For comparison, the odds of a person being struck by lightning in their lifetime are 1 in 15,300, according to the National Weather Service.

NASA will continue to update their predictions as the reentry window draws closer.

What is the Swift spacecraft?

The Neil Gehrels Swift Observatory is a multiwavelength optical, ultraviolet and X-ray telescope that launched in November 2004 on a mission to study the most powerful explosions in space. Initially designed for a two-year primary mission, the telescope ultimately spent more than 10 times that duration hunting for supernovas, gamma-ray bursts and black-hole-induced eruptions around the universe.

Swift has been rapidly losing altitude for more than a year, after rampant solar activity increased the drag on the aging spacecraft. This past August, a costly mission to boost Swift's orbit with a private spacecraft failed shortly after launch, hammering the final nail in Swift's coffin.

Engineers on the Swift team officially shut down the observatory's science operations on Oct. 20, after the spacecraft fell too low in orbit to continue taking steady observations of the sky.

As Swift goes out with a fiery bang, it leaves behind a trove of scientific data, including contributions to more than 7,000 scientific papers so far, according to NASA. This number will only increase as Swift's final observations are processed.

Earlier this year, an astronaut on board the International Space Station (ISS) snapped some striking photos, and an eerily beautiful video, of a "fireball" streaking over Earth as chunks of space debris burned up in the nighttime sky.

NASA's Chris Williams, who lived and worked on the ISS between November 2025 and July 2026, captured the eye-catching images from the station's cupola — a large, roughly dome-shaped series of windows that constantly points down at our planet — and later shared them on the social media platform X.

"Just as we were passing over West Africa, I saw a bright object directly below us, streaking through the upper atmosphere," Williams wrote in the post. "I saw its tail grow and then split apart into a shower of smaller pieces," he added. "It was quite a light show!"

Williams initially peered down at Earth to catch a glimpse of the Russian cargo spacecraft Progress 95, which successfully delivered essential supplies and additional equipment to the ISS later the same day. Instead, he saw what he believed was "some piece of orbital debris or a satellite breaking up as it entered the atmosphere."

Live Science's sister site Space.com later revealed that Williams had actually witnessed the burning remains of the Russian Soyuz rocket that had carried Progress 95 into space, after it lifted off from a recently repaired launchpad at the Baikonur Cosmodrome in Kazakhstan.

Shortly after deploying the resupply shuttle into low Earth orbit, the rocket's fairings and booster fell back toward our planet as expected, breaking apart into smaller pieces that were superheated and later vaporized by intense friction as they hit the upper atmosphere, according to Space.com. A very similar fireball was seen above Australia in August 2023, when another Soyuz rocket reentered the atmosphere.

Russia's prior resupply mission, Progress 94, also made headlines earlier this year when one of its antennae failed to deploy after separation from its Soyuz rocket, forcing cosmonauts (Russian astronauts) to use a remote control "backup system" to dock the spacecraft to the ISS.

Historically, the only fireballs visible in Earth's skies have been those caused by meteors, which can similarly break apart in flames. We were recently reminded of this when fireballs were spotted above the U.S. this spring, including one space rock that exploded with a massive sonic boom over Ohio and another that crashed through the roof of a house in Houston. (A NASA statement said the fireball Williams witnessed also may have been caused by meteor activity but was more likely to be the Soyuz rocket.)

However, fireballs from human-made objects are becoming more common. The number of spacecraft orbiting Earth has skyrocketed (pun intended) in recent decades, and "what goes up must come down."

Most spacecraft and large pieces of space junk burn up around 50 miles (80 kilometers) above Earth's surface — just below the imaginary boundary with space, known as the Kármán line. While this may lead to visually stunning spectacles like the one Williams captured, scientists are starting to realize that these fireballs may be having a bigger impact on the upper atmosphere than they previously expected.

In recent years, researchers have detected a sharp increase in atmospheric metal pollution from vaporized spacecraft. And while they are still trying to figure out what effect this may have, some scientists have proposed that it could affect the ozone layer or potentially alter Earth's magnetic field.

Additionally, as the number of falling spacecraft rises, the chances that debris may fall to Earth's surface — after failing to properly burn up upon reentry — also increase. This came to the fore in March 2024, when the remains of a 3-ton battery pack that was discarded from the ISS crashed into a family home in Florida.

See more Earth from space

Exposure to space radiation may increase astronauts' risk of a dangerous heart condition, a new study in rats hints.

The research, published Sept. 30 in the journal PLOS One, found that rats exposed to levels of radiation similar to what an astronaut might experience on a long-term trip to Mars developed more scar tissue around the small blood vessels of their hearts than rats that were not exposed to this radiation. This scar tissue is indicative of a condition known as cardiac fibrosis, which is known to increase the risk of heart failure.

This scar tissue was observed nearly a year after the rats were first exposed to the radiation.

But since this study was in rats, it cannot definitively say whether this effect will play out in humans. For example, given that humans have a longer life expectancy than rats (80 years versus 2 to 4 years), the effects seen in rats may take around 30 years to show up in humans. However, the study authors say the research highlights the importance of following astronauts' health long after they return to Earth.

"The message that we try to convey … is that the follow-up time is really important," study co-author John Baker, a professor of surgery in the Radiation Bioscience Laboratory at the Medical College of Wisconsin, told Live Science. "When astronauts come back to the Earth, they expect ‪—‬ and we expect ‪—‬ that they're going to live for a long time. I think we have to be wary that they could well develop at least some type of cardiac disease."

How space radiation affects the heart

The link between exposure to radiation and cardiac issues has been well documented. However, "no astronaut has ever been exposed to galactic cosmic radiation for long periods of time," Baker said, which makes it difficult to determine exactly how space radiation affects the heart.

Although Baker and his team previously pinpointed cardiac issues among rats exposed to radiation, this new study utilized NASA's Simulated Galactic Cosmic Ray Simulation (SimGCRSim). This new simulator provides a more precise comparison of the levels of space radiation an astronaut might experience while exploring deep space for more than a year.

During the study, the researchers exposed rats to several minutes of radiation proportionate to their size, similar to what they might experience on a trip to Mars and back (a roughly 18-month round trip, with current technology). Some of the rats' hind legs were suspended, to "simulate conditions of weightlessness," Baker said.

After 360 days, the rats that were exposed to cosmic radiation developed twice as much scar tissue around the heart's small blood vessels than unexposed rats. This buildup of scar tissue means "the heart can't relax to the point when it needs to," thereby increasing the risk of heart failure, Baker said.

This effect was not seen in the rats who were exposed only to simulated weightlessness, confirming "it was only the radiation that produced the damaging effect on the heart," Baker said. However, long-term testing revealed that this group of rats had lower levels of key immune cells, suggesting that microgravity also may affect aspects of long-term health. (Numerous studies have shown various short-term health impacts related to microgravity.)

This study "is a very valuable contribution to space biology," Rupak Pathak, an associate professor of pharmaceutical science at the University of Arkansas for Medical Sciences who was not involved in the study but holds a doctorate in radiation biology, told Live Science. While rats and humans have clear differences, "they share more than 90% of genetic information," he said, as well as very similar cardiac systems.

Given that the study authors were able to expose the rats to radiation only once, Pathak would like to see further experiments exploring whether chronic radiation exposure affects the function of the heart and other vital organs.

Baker and his colleagues hope that future experiments can be used to help NASA implement safeguards for astronauts on long-term missions, such as providing astronauts heart medications or improving shielding for the spacecraft.

"The more we know before we start, then the better NASA is going to be at working out what types of countermeasures can be developed," said Baker.

A Bronze Age man buried in a monumental tomb near the Black Sea may have died from complications of a urinary tract infection (UTI) more than five millennia ago, according to a new study. Archaeologists identified a grape-size object consistent with a kidney or bladder stone in the man's burial.

"He lived with a chronic urogenital infection," study lead author Natalia Berezina, an anthropologist at Lomonosov Moscow State University in Russia, told Live Science in an email.

"It was not a brief episode," she said. "His last years were probably marked by considerable and more or less constant pain."

Berezina and colleagues investigated a small, stone-like object found in an Early Bronze Age burial in the Stavropol Upland region of southwestern Russia. They published their findings Sept. 30 in the journal Archaeological and Anthropological Sciences.

The burial was part of a kurgan cemetery, an ancient steppe funeral tradition that involved constructing a large mound of dirt over a grave. Archaeologists discovered a catacomb when they excavated the mound, and inside was the skeleton of a man who was in his 40s when he died around 5,300 years ago. The researchers found a flint arrowhead near the man's pelvis.

But during a laboratory analysis after the skeleton was excavated, researchers noticed an odd stone-like object in the collection of hand bones. The brownish object was round with several protrusions and measured about 0.8 inches (2.1 centimeters) in diameter, or roughly the size of a grape. A small crack in the object showed a crystal-like structure inside.

To learn more, the researchers used several analytical methods to determine what the tiny object was made of. First, X-ray fluorescence analysis revealed that the main components of the object were calcium and phosphorus. Then, they used X-ray powder diffraction analysis to identify the crystal structures.

In addition to common minerals, the researchers discovered the presence of whitlockite, a rare calcium salt that is known to occur in kidney, bladder and prostate stones. These "stones," collectively called calculi, are hard masses of minerals, such as calcium-containing salts. They differ in terms of the organ they form within, the exact mechanism of how they form, and their chemical makeup, although kidney and bladder stones tend to contain very similar compounds.

Whitlockite is strongly associated with bacterial infections in the human body, which suggests that the Bronze Age man had a chronic infection that resulted in the stone, the scientists concluded.

"On the balance of the available evidence, we regard a renal [kidney] stone secondary to chronic upper urinary tract infection as the most probable origin," the researchers wrote. That is, the man dealt with chronic or recurrent UTIs, which led to the formation of the stone and likely caused him considerable discomfort. UTIs can contribute to the formation of kidney stones by altering the acidity of urine and making minerals more likely to accumulate.

The researchers aren't sure why the man had urinary tract issues or whether it contributed to his death.

Notably, kidney stones can sometimes travel to the bladder, so it's unclear exactly where the stone was in the man's body when he died. If the stone had obstructed the man's ureter ‪—‬ one of the two long tubes that connect the kidneys to the bladder ‪—‬ it may have caused kidney swelling, a secondary infection or sepsis. These conditions were frequently fatal prior to the invention of antibiotics.

Other possibilities for what caused the stone include a bacterial infection of the man's prostate gland or even a sexually transmitted infection.

The man was likely on the move frequently within this Early Bronze Age steppe society, and other injuries to his skeleton suggested he had a physically demanding life, the researchers wrote. His bones showed that he was well muscled but was also dealing with degenerative joint disease in his spine, shoulders, hips, hands and feet. He had a series of healed fractures in his right shoulder, ribs and forearm.

"These were people who worked with cattle and heavy wagons on the open steppe," Berezina said, "and the injuries that follow from that are the injuries we find." In a previous study at a nearby cemetery, Berezina and colleagues found the skeleton of a man who was injured when a wagon ran over him, several years before his death. "Against that background, four healed fractures in our man look unremarkable," she said.

But the urinary tract stone would have made the man's life difficult, the researchers noted. "This individual suffered from a painful and debilitating chronic urogenital infection, a condition that would have significantly impacted his quality of life," they wrote.

What do you know about the bones in your body? Test your knowledge with our human skeleton quiz.

Red blood cells found in a 115 million-year-old dinosaur fossil from Brazil are the oldest chemical evidence of blood-related material in a dinosaur fossil, a new study claims.

However, not everyone agrees with the research team's conclusions, with some experts saying the shape doesn't match those of reptilian red blood cells.

In the new research, published Monday (Nov. 2) in the journal PNAS, the scientists said they identified microscopic structures resembling red blood cells alongside chemical signatures of heme, the oxygen-carrying component of hemoglobin.

The new findings come from limb bones of a roughly 10-foot-long (3 meters) dinosaur called Aratasaurus museunacionali. While previous research has detected blood in dinosaur fossils, this is the first study to use chemical processes to identify heme-based signatures in dinosaur bones.

"Traditionally, fossils give us information through bones, teeth, shells and morphology. But exceptionally preserved fossils may contain another archive of information: microscopic structures and molecular traces of the original organism," study co-author Kliti Grice, a professor in the School of Earth and Planetary Sciences at Curtin University in Australia, told Live Science via email. "That opens the possibility of asking questions about ancient biology that skeletal anatomy alone cannot answer."

Deep in the bones

The team was not originally looking for traces of dinosaur blood, Grice said. Her research was driven by a broader question: How much of an ancient organism's original biology can survive fossilization?

To investigate, Grice and her team studied the limb bones of A. museunacionali, an extinct species of small theropod that lived during the Early Cretaceous period in Brazil. Theropods were a group of mostly meat-eating dinosaurs that walked on two legs. They included famous predators such as Tyrannosaurus rex and Velociraptor.

Using microscopic and chemical analysis on the theropod's limb bones, the researchers found numerous microscopic structures within vascular canals, channels that once carried blood vessels through the bone. Their shape, size and location were consistent with red blood cells, the team said.

"We combined microscopy, mineralogical analyses and molecular geochemistry," Grice said. "Critically, we investigated the chemistry in situ [in the bone itself], so we could relate the chemical signals to the microscopic structures in their physical context within the fossil. That is much stronger than simply extracting molecules from a piece of fossil and assuming where they originated."

The team's chemical analyses detected preserved heme-related compounds associated with these structures, providing more chemical evidence to support the idea that the finding could be traces of dinosaur blood, as heme is the iron-containing, ring-shaped molecule that forms a key part of the molecule hemoglobin in red blood cells.

A time capsule

Grice and the team think the conditions the theropod dinosaur was buried in could have helped preserve the vascular structures and the red blood cells within them. They suggested that the animal was rapidly covered by sediment in a low-oxygen environment containing microbial mats ‪—‬ thin biofilms made of microorganisms. These conditions may have altered the normal process of decomposition, helping to preserve the microscopic structures and associated chemical signatures.

"The red-blood-cell-like structures were mineralised with hausmannite, a manganese oxide mineral (Mn₃O₄)," Grice said. "We think early mineralisation helped stabilise or replicate microscopic biological structures before they were completely destroyed, while aspects of the associated chemistry also survived in altered form."

The fossil also contained preserved amino acids associated with collagen, the structural protein found in bone.

Not everyone is convinced

While blood has been found in dinosaur fossils before, not everyone agrees that these latest findings are truly red blood cells.

"I very much appreciate this team bringing rigor to the study of deep time fossils," said Mary Schweitzer, a molecular paleontologist at North Carolina State University who was not involved in the study but has previously studied soft tissues from the dinosaur age. "I am in agreement that endogenous [produced within the body] molecules can persist over geological time in some form, and that there is much these can teach us. However, I am not convinced that the images they figure are remnant RBCs [red blood cells] for several reasons."

For one, the structures do not convincingly match the expected appearance of red blood cells in nonmammalian animals, Schweitzer said. Unlike mammalian red blood cells, which lose their nuclei during development, those of birds and reptiles retain their nuclei. This typically produces a characteristic nuclear bulge in the shape of the cell.

According to Schweitzer, the latest findings show the microstructures having more of a concave shape with no nuclear bulge. The structures also were smaller than most non-mammalian red blood cells, "so morphological similarity is not met," Schweitzer said.

"I appreciate these authors bringing technological innovations to the study of dinosaur fossils," she said. "I am excited to see that this team and others are moving forward with a molecular approach to ancient fossil remains."

Editor's Note: This article was updated at 5:44 p.m. E.D.T. to remove an outside comment that suggested the study did not include resonance Raman spectroscopy. The team did perform that analysis.

Egyptian researchers have found a hidden 2,600-year-old structure the size of a football field after using satellites to peer below the ground. But what they found beneath the structure may be just as remarkable as the building itself.

The site they examined is known as Buto (modern-day Tell el-Fara'in), a sprawling mound of layered history in the northwestern Nile Delta. To the ancient Egyptians, it was the sacred home of Wadjet, the cobra goddess of Lower Egypt, and one of the most religiously important cities in the pharaonic landscape.

Archaeologists have excavated its upper layers for decades, finding remains from the rule of the Macedonian Ptolemaic dynasty (305 to 30 B.C.) and Roman era (30 B.C. to A.D. 395). But the deeper, older layers at the site — including a mound called Kom C, sitting below groundwater level in waterlogged delta clay — had stayed stubbornly out of reach. Kom C itself rises above the surface as a visible mound, but earlier excavations had reached only the Ptolemaic and Roman layers before hitting the water table.

Now, researchers have turned to noninvasive tools, including satellite imagery, to delve into the mysterious subterranean layers.

First, they turned to the European Space Agency's Sentinel-1 satellite, which can produce radar images by beaming down microwave pulses from orbit and then measuring how they reflect back; the returning signals can reveal subtle differences in surface moisture, elevation and reflectivity that can hint at buried structures beneath the ground. After looking at these radar images, the team spotted a large oval-shaped anomaly buried beneath Kom C that was 420 feet long and 203 feet wide (128 by 62 meters).

To learn more without disturbing the site, the team ran 15 parallel lines of electrical resistivity tomography (ERT) across an area of roughly 58,100 square feet (5,400 square meters). This technique reveals the underground landscape by passing electrical currents through the earth, measuring how they travel and creating a map that archaeologists can read.

The picture that came back was layered. Between the surface and 10 feet (3 m) down, the team found scattered Ptolemaic and Roman debris, including displaced mudbricks, pottery shards and broken limestone, which point to centuries of continued occupation and rebuilding on the site. Later residents dismantled older structures for reuse and left a scatter of displaced material behind.

Deeper still, between 10 and 20 feet (3 and 6 m), the researchers found a large mudbrick structure from the 26th dynasty (688 to 525 B.C.), also known as the Saite period. They were able to date this discovery based on its layer, the unique shape of the mudbricks and other artifacts such as pottery, which the team dated by style and their archaeological layer, with carbon-14 dating applied to associated organic material. The large structure may be a tomb, a house for priests or a religious shrine, the team wrote in the study, published in March in the journal Acta Geophysica.

And below that, at 20 to 23 feet (6 to 7 m) underground, the researchers unexpectedly found a thick, clean layer of sand.

That sand is the discovery within the discovery, the team wrote in the study.

The Nile Delta's clay is notoriously treacherous to build on. It absorbs moisture and swells, and then contracts and shifts as it dries — posing a slow-motion threat to anything heavy sitting on top of it. The Saite builders, it seems, knew this. Before laying the foundations to their structure, they packed a cushion of clean sand beneath it. This sand would have spread the building's weight, let groundwater drain through, and stopped the clay from creeping. It is the same logic behind modern load-distributing foundations — applied here more than two and a half millennia ago.

"By combining satellite radar with deep ERT profiles, we didn't just map the walls of this massive Saite-era structure — we were also able to analyze the subsurface layers," study co-author author Abdelaziz Elfadaly, an associate research professor at Egypt's National Authority for Remote Sensing and Space Sciences, told Live Science. "The detection of a significant, clean sand foundation layer beneath the mudbrick walls explains how these heavy structures survived the high water table and shifting clayey soil of Buto."

The sand layer, in effect, acts as a barrier; it stops groundwater from wicking upward into the mudbrick, which would soften and dissolve it. The sand also lets water drain sideways instead of pooling against the foundation, according to Elfadaly.

A 3-by-3 foot (10 by 10 m) excavation trench that was around 20 to 23 feet (6 to 7 m) deep confirmed the presence of thick mudbrick walls resting on that sand layer, and nearby, a spread of objects that hint at the site's sacred function. According to Elfadaly, these finds included ushabti and shawabti figurines — small servant statues typically placed in tombs to serve the deceased in the afterlife — and a limestone altar whose carved channels bore dried residues consistent with animal blood, pointing to offering rituals performed at the site. The study also noted a rarer find: a faience baboon figurine, the kind associated with Thoth, the god of wisdom.

The Saite period was a moment of cultural revival. After generations of Assyrian and Libyan domination, Egyptian pharaohs retook the throne and poured resources into restoring Egypt's religious landscape, particularly in the Nile Delta, which had been their power base. Buto, with its deep ties to Lower Egyptian identity, was a natural focus. The Saite kings ruled from the nearby delta city of Sais, so restoring Buto reinforced their roots and their claim to the throne.

"A monumental building of this scale underscores the Saite pharaohs' intense commitment to glorifying the Delta region," Hussein Bassir, director of the Antiquities Museum at a cultural research center known as Bibliotheca Alexandrina who wasn't involved with the study, told Live Science in a WhatsApp message. "Using pure sand as a stabilizing cushion was a brilliant, deliberate tactic — the ancient builders profoundly understood their environment."

The team is planning a return visit, this time using wider-spaced electrical resistivity surveys to reach deeper layers, along with specialists who study ancient plants and also understand how geological features changed over time, which may help reconstruct what the landscape around Buto looked like when these walls were first laid.

Are you a fan of mummies and hieroglyphs? Find out with our ancient Egypt quiz!

For decades, psychiatrists and other mental health professionals have used the "Diagnostic and Statistical Manual of Mental Disorders," or DSM, to diagnose patients with conditions such as major depression, anorexia and post-traumatic stress disorder (PTSD). To reach diagnoses, mental health practitioners identify symptoms via interview, case history, questionnaire, or observation to paint a clinical picture.

But for the next version of this "psychiatry bible", the DSM-6, scientists are planning to add other factors into the diagnostic criteria.

Dr. Anand Kumar, a psychiatrist who served for two years on the DSM Strategy Committee, says one of the most important potential changes is the introduction of biological factors into the diagnostic framework. While Kumar, the head of the Department of Psychiatry at the University of Illinois Chicago, no longer serves on the committee, he was influential in discussions about how biology could be incorporated into the DSM-6. Some of these biological factors include data from genome-wide association studies of hundreds or thousands of genes that each increase the risk of a mental disorder by a tiny amount. Other biological factors include signs of inflammation or immune-system dysfunction that may show up in blood tests or brain scans.

Live Science spoke to Kumar about how this update to the DSM could change the way mental disorders are understood and potentially help improve treatment.

Kenna Hughes-Castleberry: How is the DSM-6 going to be different from the DSM-5?

Anand Kumar: Up to this point, the distinctions between the different major groups — who has clinical depression, or what we call major depression; who has an eating disorder; who has PTSD, etc. — have been based exclusively on clinical grounds: You meet certain criteria, and you fall into this category. If you meet some other criteria, you fall into another category.

An attempt that's being made now, one of the major attempts for the next DSM, is to introduce biological factors into the manual.

The idea is not new. It's been discussed in the past, but it was difficult to get a consensus on what goes in and what should not go in. That's still going to be tricky, but at least there's a broad acknowledgement that the time is ready to start introducing biology into the DSM.

It's very likely that, at the end of it, there will be meaningful changes in a positive kind of way. It's not going to make everyone happy. There are going to be gaps, but the idea is to incrementally improve this and make it more modern as we go along.

KHC: What sort of biological markers have you seen that we can actually correlate with these disorders?

AK: What the committee is doing is taking a more nuanced approach. Outside the realm of Alzheimer's disease, which I'll get into in a minute, there are no clear-cut diagnostic biomarkers — meaning no blood tests or brain scans that you can look at and say, "This person has a diagnosis of depression," or "This person has PTSD," or "This person has schizophrenia."

The committee talked about how, in addition to biological biomarkers, there's a concept of biological factors. What I mean by that is biological pathways and mechanisms that have a role in the development of a particular disorder, but the findings have not crystallized into a laboratory test.

For example, immunology — the study of the body's response to a variety of stresses, including infections and others — has been shown to be impactful in about 30% of cases of major depression. Yet there is no single biological laboratory test that is currently available that can be used [to diagnose immune-mediated depression] in clinical practice. So these come under the category of what we call biological factors.

In the Alzheimer's disease field there are clear-cut biomarkers. There are now blood tests for proteins called tau and amyloid that have been approved by the FDA [Food and Drug Administration] as biomarkers for Alzheimer's disease. Meaning, if you have a clinical picture and a mental-status exam consistent with intellectual decline, you must have a positive biomarker test to be categorized as having definitive Alzheimer's disease.

And that's new. Ten or 15 years back, there were brain scans, and if you did a lumbar puncture, you could find these proteins in the spinal fluid. But those are invasive. Now you actually have a blood test.

But that degree of precision, for lack of a better term, is not available in the other branches of psychiatry. Nonetheless, there are clues that other pathways and mechanisms are involved.

I mentioned immunology as one. Another big elephant in the room is genetics.

Most people think of genetics as an abnormal gene or a mutation — meaning a gene switches or changes and confers increased risk — as one mutation causing one disease. That's how most people in the general public think about mutations: They cause disease.

But when you get into complex diseases like heart disease and diabetes, there are multiple genes involved. And diseases may or may not be caused by a gene. Abnormal genes may or may not cause the disease, but they increase risk.

With mental disorders, the situation becomes immensely more complicated. It's not just a few genes here and there. There are hundreds of genes, each increasing the risk for depression, schizophrenia and anxiety disorders by a small amount.

So while there is no single genetic test that can now be used, large numbers of genes have consistently been shown — and many of the recent studies are strong — to be associated with certain disorders. But because there's no single gene or small group of genes, we cannot walk away from the science. Complexity doesn't mean we throw our hands up and say, "Well, it's all too much."

It may seem overwhelming, but genetic profiles are better understood today than they were 20 years ago. So that's something else this committee is thinking about and I think should take into account going forward: to somehow incorporate that into the diagnostic categories.

KHC: Do you think there's any sort of risk with adding those biological factors into the DSM?

AK: I don't think so, because if you think about genetics, it's not going to be introduced as a biological test.

Most folks know that mental disorders, like other medical disorders, run in families. And genetics is the most plausible explanation for that. What this does, I hope, is introduce a degree of more comprehensive description of these disorders. So when a busy clinician looks at it, it confirms what they already suspected: There's a family history here, and family history means genetics.

It's complex, many genes are involved, and it produces a better characterization of this. The diagnosis is still going to remain clinical, but this provides a biological context, very much like, say, diabetes or heart disease.

Genes and environment cause a variety of medical disorders. With heart disease, there's no one gene. When cardiologists develop a risk profile for heart disease, it includes genes, other physiological factors such as BMI, which is the weight-height ratio, diet and a variety of environmental factors.

That degree of classification is missing today in mental health and psychiatry. We hope this is a first step in correcting, if you will, those conceptions about what causes these disorders.

KHC: How would you end up using this in a psychiatrist's office to guide treatment?

AK: I can give you one possible example. I'm reaching a bit.

There's a term commonly used in clinical psychiatry and psychology called comorbidity. What it means is that people who are diagnosed with depression also have anxiety, or people who are diagnosed with an anxiety disorder also have substance abuse or alcoholism in general.

That is not coincidental. It's not something that we just somehow find. A lot of these disorders share genes.

For example, about 45%, roughly, of patients diagnosed with a major mood disorder also have an anxiety disorder. And you flip that around: About 45%, roughly, of patients diagnosed with an anxiety disorder — it could be generalized anxiety disorder, what we call PTSD, or a phobia — also have a mood disorder.

I think when clinicians classify them together, not as the same disorder but as sharing a lot of psychological as well as genetic risk, clinicians should be on the lookout for both. A patient with a mood disorder, for example, could either now or at some later point develop an anxiety disorder. Or someone with an anxiety disorder is at risk for substance abuse.

So treatments need to be tailored a little more broadly. I'm hoping that'll be something clinicians think about when they talk to patients and their families.

KHC: What do you think is the most unique aspect, from your perspective, of this upcoming DSM-6?

AK: My bias is the biology. I say this because a lot of the other things, the cultural factors, etc., are largely appreciated, and they'll be better characterized. Some things like cognitive changes, such as working memory and attention [tests], are not unique to any given disorder.

Biology will be qualitatively new when introduced into the DSM, and I hope it's done well. I hope that they do it appropriately, and I think they will [do it] correctly.

It's not going to be perfect, but it's going to be a first step. I think introducing the idea that genetics, immunology and other factors are very important in the causation of mental disorders, and explain some of the phenomena that we previously could not find an explanation for, is — I hate to use the word "leapfrog" — but that's kind of what it is.

It moves the field conceptually forward, and not as a slow, steady, gradual increase. For the DSM, it would be an important step forward.

This interview has been condensed and edited lightly for clarity.

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The Lycurgus Cup is a Roman-era glass goblet that changes color from jade green to ruby red depending on if a light is shining on its front or back. But experts are unsure where the cup was found, where it was made, or whether the glassblower who made it created the color-changing effect on purpose.

In 1958, the British Museum acquired the cup from the Rothschild banking family, which had owned the artifact since the mid-19th century. Known colloquially as the Lycurgus Cup for its depiction of the mythical king who angered the god Dionysus, the glass is about 6.3 inches (15.9 centimeters) tall and weighs around 1.6 pounds (700 grams).

The glass is a remarkably well-preserved example of a Roman "cage-cup," according to a 1959 study of the artifact by archaeologists D. B. Harden and Jocelyn Toynbee. Only a handful of cage-cups still exist, and experts believe the goblets were made by cutting and grinding decoration into thick glass. Because small bridges were left to ensure the decoration remained on the glass, the overall effect is like a cage. Harden and Toynbee estimated that the Lycurgus Cup was manufactured in the fourth century, likely in Italy, but they noted that the bronze frame that forms the stem and rim of the goblet is probably a 19th-century addition.

Depicted on the cup is the myth of the punishment of Lycurgus, king of the Thracian tribe called the Edoni (also called the Edonians). Lycurgus did not approve of the worship of Dionysus and banished the god into the sea with an ax. But one of Dionysus' priestesses, Ambrosia, decided to fight Lycurgus. Ambrosia changed herself into a vine and wound herself around Lycurgus, who was unable to escape. The other priestesses thronged around them and tormented Lycurgus. Given that Dionysus was a god of wine and merriment, the depiction of Lycurgus' punishment may have been particularly appropriate for this goblet. Additionally, the change in color from green to red may have been meant to mimic the ripening of grapes on the vine.

Color-changing cups, also called dichroic cups, were mentioned in ancient Roman historical records. For example, a second-century letter possibly penned by Emperor Hadrian to his brother-in-law mentions a gift of two dichroic cups to use during banquets. But very few fragments of this mysterious type of glass survive today, a 2007 study noted.

For decades, experts have been working out how ancient Romans produced dichroic cups, and some have even replicated the Lycurgus Cup's color-changing effect. A 1963 study confirmed that the key seems to be the addition of microscopic nanoparticles of gold and silver during glassblowing that produce the appearance of milky-green glass when lit from the front and nearly translucent red glass when lit from behind. The metal nanoparticles are smaller than grains of sand and interact with light, creating the perception of a color change.

A replica of dichroic glass made by Corning Glassworks in the 1960s went from green to amethyst in the light, the 2007 study reported, and in 2020, researchers included silver and gold nanoparticles in 3D printing to replicate the color-changing properties of the glass.

More recently, experts at the University of Sheffield in the U.K. reproduced the dichroic glass by reverse-engineering the "recipe" from the original Lycurgus Cup. The team then commissioned a glass artist to create a Lycurgus-inspired design from the replica.

But because so few examples of dichroic glass exist, experts are still unsure whether Roman artisans created the color-changing effect on purpose or whether traces of gold, which would have been available in an ancient craft studio, slipped into the molten glass and made a rare and unusual material that mystified even the most skilled glassblowers.

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

Can you put together last week's Astonishing Artifact?

For nine months, a scientific expedition searched for blue whales in the waters around the Galápagos Islands but found none. Between October 2025 and July 2026, the researchers surveyed areas of the Ecuadorian archipelago where the giants had historically been recorded, hoping to attach satellite tags and learn more about the animals' migratory routes. The search ended without the team tagging a single whale.

The absence coincided with unusually warm ocean conditions during an El Niño event. Sea surface temperatures were as high as 82 degrees Fahrenheit (28 degrees Celsius), while at a depth of 330 feet (100 meters) water temperatures ranged from 66 to 67 F (18.9 to 19.4 C) — up to 9 F (5 C) warmer than usual for that time of the year.

This raised the possibility that El Niño changed where blue whales were finding food and, in turn, where they went. The researchers suspect the animals may be seeking colder, more productive waters. However, the whales themselves are still missing.

"The hypothesis is that the whales are staying in areas with greater productivity [more food] farther south, in waters with slightly cooler temperatures," Daniela Alarcón, the expedition's leader and a researcher at the Universidad San Francisco de Quito's Galápagos campus and the Galápagos Science Center, told Live Science.

As to where the missing whales have gone, possibilities include the waters off Peru and offshore areas where the animals could go undetected. In this scenario, the unusually warm waters around the Galápagos Islands would act as a "temperature barrier," Alarcón said, preventing them from feeding in the archipelago's waters.

Why water temperature matters

Blue whales (Balaenoptera musculus) can consume up to 12,100 pounds (5,500 kilograms) of krill — small crustaceans that make up the whales' primary food source — every day. That means they need to find areas with enough food to sustain them.

"These are very large animals that need to move to areas where they can keep feeding," Alarcón said.

It's not yet clear whether this year's El Niño caused a krill shortage in the waters off the Galápagos, but some indirect evidence points that way.

Past expeditions suggested that blue whales tend to feed in water layers around 71 F, which this season was identified around the Galápagos at a depth of about 197 feet (92 m). By contrast, peak chlorophyll concentrations, an indirect indicator of abundance of the krill's food source, phytoplankton ‪—‬ were recorded much higher in the water column, at between 39 and 121 feet (12 to 37 m) below the surface. Because krill abundance wasn't directly measured, that data suggests, but does not establish, that there was a mismatch between the whales' preferred feeding layer and the presence of their food.

"Honestly, we had never encountered such unusual conditions before," Juan Pablo Muñoz, a marine biologist at the Universidad San Francisco de Quito who was also on the expedition, told Live Science.

Continuation of a trend

The whales' absence did not come as a complete surprise to the team. Sightings had already begun to decline before the most recent expedition. Reports submitted through Cetácea Galápagos, a citizen science network, began to dwindle between August and September 2025. There were two isolated reports of blue whales, in May and June 2026, but the team could not confirm either one, despite intensifying its search.

"We knew conditions wouldn't be the same, but we thought that if we put in more effort, we might be able to find some individuals. But we searched, and searched, and searched — and found nothing," Alarcón recalled.

Part of that could be down to the elusive nature of the giant creatures. Humpback whales (Megaptera novaeangliae)are generally easier to spot, Muñoz noted. In some places, they can be seen from the shore or after a half-hour boat ride. Blue whales, by contrast, rarely approach mainland Ecuador's coast and tend to stay far from populated areas in the Galápagos.

Sensitive to temperature fluctuations

Fernando Félix, a marine biologist at the Pontifical Catholic University of Ecuador who was not part of the expedition, was unsurprised by the result.

"We already knew there wouldn't be any blue whales in the Galápagos," said Félix, who is also a researcher at the Whale Museum (Museo de Ballenas).

Félix told Live Science that there are historical precedents for this behavior in the southeastern Pacific. During the 1982-1983 El Niño, which also brought substantial ocean warming, blue whales and other species, including fin whales (Balaenoptera physalus) and Bryde's whales (Balaenoptera brydei), were recorded shifting southward.

"We might think that because they are 'just animals,' they lack memory or don't understand these processes — but we would be wrong," Félix said. "They can clearly sense that when temperatures are unusually high as they travel north from the south, vertical mixing has been disrupted and there is no food in the Galápagos. They perceive environmental conditions and naturally direct their movements toward areas where they believe feeding conditions are better."

Rather than indicating a mass die-off, the whales' disappearance may reflect a shift in their movements in response to changing ocean conditions, Félix said.

"I don't think the whales have died," Felix said. "They simply didn't go to the Galápagos region. They went elsewhere, where conditions were better."

This response to environmental conditions may also have impacted dolphin movements. Pods may have moved toward colder waters, where food could be more abundant, or may have even dispersed, Félix suggested.

When will blue whales return to the Galápagos?

El Niño's effects will likely persist over the coming months. "Between January and May 2027, we'll have warm water coming from the north and warm water coming from the west," Félix warned. "This is going to hit us extremely hard."

Blue whales, humpback whales and dolphins would likely return to Galápagos waters once El Niño subsides and ocean conditions begin to normalize. He said pelagic fish (species that live in the water column rather than on or near the seafloor) ‪—‬ including tuna, swordfish, anchovies and sardines, which have also moved toward colder waters ‪—‬ would return as well.

Muñoz agreed. Krill populations can rebound just one to three months after cold, nutrient-rich waters begin to rise to the surface. More whale sightings were recorded in the years following the 2015 and 2023 El Niño events. Based on these precedents, he suggested that 2028 could be a promising year if cold water returns to the surface. "The system bounces back," he said.

Félix compared El Niño to a computer restart. "It resets the environment, allowing ecological processes to begin again," he said. He's confident that blue whales will return to the area. "I can guarantee that there will be large numbers of blue whales at this time in 2028," he told Live Science.

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In space, nobody can hear you scream — or meow, for that matter. This was as true for Félicette — the stray Parisian tuxedo cat who safely completed the world's first (and only) suborbital feline flight, in 1963 — as it is for the gargantuan Cat's Head Nebula, which is featured in stunning new images from the Hubble and James Webb space telescopes.

Rising from the cloudy Carina Nebula some 7,500 light-years from Earth, the Cat's Head Nebula is a column of star-sculpted gas and dust that vaguely resembles a feline sitting with its back to us, coyly turning its head to show off a single red eye. That eye is a young star that's embedded deep within the dust and possibly transforming it before our eyes.

Nebulas like these occur when the radiation from active young stars lights up and erodes the material around them. They are beautiful and easy to find; if this cosmic cat gets bored staring at us, it can just waltz over to the other side of the Carina Nebula and crawl into a similar globule of gas that looks exactly like a box with an open lid. (Cats will be cats, after all.)

In honor of Halloween, the European Space Agency (ESA) shared three competing views of the Cat's Head Nebula — one from the Hubble Space Telescope, which captures optical light, and two from the infrared instruments aboard the James Webb Space Telescope (JWST). The three views, shown below, reveal different features of the nebula in different wavelengths of light, getting progressively spookier as more color drains out of the scene.Take a look at all three images — and cast your vote for the spookiest in the poll at the end.

Hubble's view

Observing the nebula in the same visible wavelength range that you could see through a strong backyard telescope, Hubble highlights the dark pillar of dust that has survived the ultraviolet assault of nearby stars. The wispy edges at the right of the column show where starlight is evaporating the gas around it, slowly whittling it away to nothing.

The glow of blue, yellow, orange and red light around the dust pillar mark where starlight is interacting with different gas molecules, including oxygen, hydrogen and sulfur, according to ESA. The process is similar to how different molecules in Earth's atmosphere produce different-colored auroras when excited by solar radiation — just on a much grander scale.

JWST's near-infrared view

Switching to light human eyes cannot see, JWST's Near-Infrared Camera cuts through the wispier outer layers of dust to show the densest material at the column's center. Countless additional stars and galaxies appear in the field of view as their infrared glow penetrates the surrounding material.

Here we see a more complex, turbulent column, showing how stellar radiation is carving up the inside of the cat's head as well as its edges. JWST's view also illuminates a disembodied, hand-like structure to the left of the cat, reaching out as if to pet its cosmic companion.

JWST's mid-infrared view

The final view, taken with JWST's Mid-Infrared Instrument, cuts to the ghostly core of the nebula, showing little more than smoky, bluish light. According to ESA, these are the emissions of molecules called polycyclic aromatic hydrocarbons — typically colorless molecules of carbon and hydrogen related to combustion.

While most starlight disappears in this view, a strange new bright spot emerges to the right of the cat's head. This orange speck is a true mystery, according to ESA, and its relationship to the rest of the nebula is unknown.

Each year, Earth's Northern and Southern hemispheres cycle through four seasons, including summer.

Given that the hemispheres are symmetric about the equator, you may think that, on both sides of the world, summers should be similar – both in terms of their climate and factors like their length. But are Northern and Southern hemisphere summers really the same?

Climate experts tell Live Science that they differ quite a bit — and that comes with a clear recommendation for sun enthusiasts.

The most obvious difference is that Northern and Southern summers happen at different times. According to NASA, this arises because Earth's axis is tilted 23.4 degrees relative to the plane of our planet's orbit around the sun.

This tilt causes the Northern and Southern hemispheres to be oriented toward the sun at different times throughout the year. Between the Northern Hemisphere's summer solstice and autumnal equinox, the Northern Hemisphere is oriented toward the sun, resulting in summer, and vice versa in the Southern Hemisphere.

This means that summers between the Northern and Southern hemispheres sit six months out of sync with each other — with Northern summers spanning late June to late September and Southern ones going from late December to late March. (Summers are also defined meteorologically, or relative to changes in weather phenomena, as being the hottest months of the year. Under this definition, Northern summers run from June to August, and Southern ones go from December to February.)

Northern summers are longer

Another difference between Northern and Southern summers is their duration. According to NASA, Northern Hemisphere summers are, on average, 4.5 days longer than Southern Hemisphere summers. (This is with respect to the astronomical definition; meteorologically, Northern summers are longer than Southern ones by two days in non-leap years, but this is due to February being the calendar's shortest month.)

The 4.5-day difference occurs because Earth's orbit around the sun is slightly elliptical instead of perfectly circular, according to NASA. Consequently, Earth's orbital velocity (the speed at which our planet hurtles around the sun) isn't constant.

During the Northern Hemisphere's summer, Earth is farther away from the sun and thus moving more slowly, said Georg Feulner, a senior researcher at the Potsdam Institute for Climate Impact Research in Germany. This is due to Kepler's second law of planetary motion, he added.

This means that at aphelion ‪(the point at which our planet is farthest from the sun)‬ Earth is traveling at 18.2 miles per second (29.3 kilometers per second). This jumps to 18.82 miles per second (30.29 km/s) at perihelion ‪(the point when Earth is closest to the sun ) which occurs during Southern summers.

While this may seem like a tiny difference in speed, it causes our planet's path around the sun to be 53,686 miles (86,400 kilometers) shorter in a 24-hour-interval at aphelion compared with at perihelion. In other words, Earth covers more "ground" at aphelion than at perihelion over a 24-hour-interval. "Therefore, the time between the Northern Hemisphere spring and autumn equinoxes is longer than the time between the Southern Hemisphere spring and autumn equinoxes, Feulner told Live Science in an email.

Northern summers are hotter

A third point of difference is that Northern summers are typically hotter than Southern ones. A 2015 study in the journal Climate Dynamics showed the precise value of this depends on whether temperatures are measured on the surface air, land or ocean, and the latitude at which they're taken. Nonetheless, when averaged over all domains and latitudes, Northern summers are 7.83 degrees Fahrenheit (4.35 degrees Celsius) hotter than Southern ones.

So what's behind this? Earth's changing distance from the sun isn't important. If it were, Earth's aphelion crossing during Northern summers should make them cooler than Southern summers during the perihelion crossing. Instead, several other factors are responsible.

One is the Northern Hemisphere's bigger fraction of land compared to its large water bodies like oceans. "Land has a lower heat capacity than water and so increases temperature more for a given heating than water does," Richard Seager, a professor at Columbia University's Lamont-Doherty Earth Observatory, told Live Science in an email. As a result, the many inland sites in the Northern Hemisphere heat up rapidly and have higher summer temperatures, according to the UCAR Center for Science Education.

Additionally, Seager said, another difference lies in the way heat is distributed through air and water. The solar heat that land receives warms only the first few feet of the atmosphere, while the heat water absorbs gets mixed throughout its depths. This makes the Southern Hemisphere — with its larger fraction of water — cooler over summer.

The second factor for the North Hemisphere's higher summer temperatures are cross-equatorial ocean currents. Such currents cross the equator, transferring water and heat between the hemispheres. The primary current is the Atlantic Meridional Overturning Current (AMOC). "The AMOC transports heat from the SH [Southern Hemisphere] to the NH in the Atlantic," Feulner said. This warms Northern oceans and seas, which, in turn, heats up adjacent land-masses.

So, Northern Hemisphere summers are longer and hotter than Southern ones. If you want to stretch out your summer, you now know where to go.

How much do you know about our blue planet? Test your terran knowledge with our Earth quiz!

The mysterious force that cleared the cosmic fog at the dawn of the universe may not be what we thought, a new study suggests. The results hint that astronomers may need to rethink a major aspect of cosmological evolution, which led to the universe we clearly see today.

Around 400,000 years after the Big Bang, the fledgling universe finally cooled enough to form atoms — mostly hydrogen. But these neutral, non-electrically charged hydrogen atoms shrouded the cosmos in a fog that made it opaque to ultraviolet (UV) light.

Then, after the first stars flickered to life and gathered into galaxies, bursts of radiation ionized the neutral hydrogen. This turned the impenetrable fog of atoms into electrically charged protons and electrons, allowing light to pass through interstellar space unimpeded and, eventually, reach our observatories. This cosmic curtain parting is known as the Epoch of Reionization, or what a team of researchers studying it call the "last major phase transition in the universe."

"We don't know exactly what objects caused reionization or how it evolved," Cody Carr, an astronomer who focuses on galaxy evolution at the University of Michigan and first author of a new study of the epoch, said in a statement. "We know that it took place, but we don't have complete answers to those questions."

Astrophysicists previously thought that this fog-clearing effect depended on supernovas, the violently explosive deaths of stars around eight to 50 times the mass of the sun.

But in the new study, published Oct. 15 in the journal Nature Astronomy, Carr and colleagues presented evidence that supernovas exerted the opposite effect, trapping the so-called Lyman continuum (LyC) photons of ionizing UV radiation that dispelled the celestial fog instead of scattering them.

"The most interesting thing about our paper is the observation that the strongest LyC emitters do not have fast galactic winds," Carr told Live Science via email. "This challenges the notion that galaxies require fast supernova-driven winds to enable LyC escape."

Which way the winds blow

The researchers used the Hubble Space Telescope to observe an analogue of the ancient universe in the local cosmos: six star-forming, wind-launching galaxies around 3.5 billion light-years away.

These compact starburst galaxies are generally smaller than 6,500 light-years in diameter and form around 10 solar masses' worth of stars per year. That star-birthing rate is several times higher than that of the Milky Way, which is up to 20 times larger.

The galaxies' spectra, or light-based fingerprints, revealed the origin, chemical composition, speed and direction of their stellar winds, which were whipped up by the radiation from their newly formed stars.

The researchers also described how these processes changed as the massive young stars evolved and died in energetic supernovas several billion years later, with the resultant galactic winds overpowering the stellar winds.

These nearby galaxies highlighted a counterintuitive two-phase process.

In the initial phase, which occurred during the first 3 million years of star formation, the newly formed massive stars' stellar winds carved through their galaxies' neutral gas and dust at nearly 2,000 miles per second (3,000 kilometers per second). This allowed LyC light to escape the galaxy and ionize the neutral gas and dust in intergalactic space.

The second phase, which emerged around 3 million years after star formation, seemed to reverse this process. As O-type stars — the hottest, bluest and most massive stars in the cosmos — lived fast and died young, their expelled stellar guts added to the opaque galactic gas and dust, churning it and loading it with mass, which created a trap for LyC light.

The oldest galaxies in this study ‪—‬ and, therefore, the ones with the fastest supernova-generated galactic winds ‪—‬ allowed the least amount of ionizing radiation to escape their environs.

"In general, our results are in disagreement with most cosmological simulations, which typically show the LyC escape fraction peaking after the launch of supernova-driven winds," Carr explained via email. In other words, supernovas didn't drive the Epoch of Reionization, but they may have dampened it. The intense light of newborn stars now seems like the most viable source of reionization.

Future research could aim to obtain additional galactic samples and higher-resolution observations across other wavelengths.

Archaeologists have discovered a ghostly human-shaped artifact at a fifth-century burial mound in Japan. The clay figurine's appearance suggests it represents a female shaman who once guarded a tomb.

The artifact was unearthed at the archaeological site of Nishikaminomiya, northwest of Tokyo, according to a translated statement from Japan's Gunma prefectural government. At the site, archaeologists found nearly a dozen burial mounds known as "kofun" dated to the fifth and sixth centuries.

This time period in Japanese history, which lasted from about A.D. 300 to 710, is called the Kofun period. Many tombs in this period had cylindrical clay sculptures called "haniwa" that were used as offerings to the dead and were often thought to contain the souls of the deceased.

The newly unearthed haniwa is about 16 inches (40 centimeters) tall; but only the head and torso remain, so it would have originally been a lot larger. The figurine was discovered in a moat around an enormous burial mound that measured about 145 feet (45 meters) in diameter. It's likely that the haniwa was originally placed near a boat-shaped sarcophagus archaeologists discovered in the mound and that it slipped down the hill over time to land in the moat, according to the statement.

Experts think the haniwa represents a female shaman known as a "miko," or "shrine maiden." These priestesses bridge the gap between the human and spiritual realms in the Shinto religion. During the Kofun period, miko would have performed important funeral rituals and offered spiritual guidance.

The haniwa figurine has a traditional Japanese topknot hairstyle called a "shimada," which indicates that the haniwa represents a miko, according to the statement. Both of the figurine's wrists have bracelets made from clay and red pigment. The haniwa's fingers have been carefully molded, and the figurine has a prominent nose. In addition, she wears a red sash painted on her torso and holds a rod-shaped ritual implement in her left hand.

"These details suggest that considerable care was taken in making the figure, even in features that would not be visible from a distance," representatives of the Gunma prefectural government said in the statement.

Archaeologists discovered the haniwa this year during excavations of the main burial mound at Nishikaminomiya, but they have been working at the site since 2020.

The haniwa is currently on display at the Gunma Prefectural Archaeological Research Center's Excavation Information Museum in the city of Shibukawa.

The iconic nature documentary "Blue Planet" is set to return with a splash this weekend as Sir David Attenborough narrates the third installment of the BBC series. The six new episodes promise to take us deeper into the world's oceans than ever before, so wherever you are in the world, here are all the TV and streaming you need to dive right in.

The new season promises to push the boundaries of underwater wildlife filmmaking, using next-generation camera technology including "splash drones" that can land, float and take off directly from the water.

Whereas "Blue Planet II" (2017) exposed the impact of plastic pollution, each episode of "Blue Planet III" shifts the focus to "stories of hope and recovery" across five spectacular marine habitats: tropical seas, open ocean, seasonal seas, polar waters and the deep.

The sixth and final episode, "Future Seas," will look ahead to the challenges facing our oceans and what we can do to protect them for future generations.

Read on as we show you where to watch "Blue Planet III" online and on TV.

How to watch "Blue Planet III" in the U.K.

"Blue Planet III" premieres on BBC One at 8 p.m. on Sunday, Nov. 1, and will also be available to stream on BBC iPlayer.

BBC iPlayer is a free streaming platform for U.K. viewers — although you will need to confirm that you have a TV licence.

Watch "Blue Planet III" from anywhere

If you're traveling abroad you can access your usual streaming services from anywhere with a good VPN.

A VPN — or virtual private network — is a piece of internet security software that can alter your device's digital location, unlocking the geo-restrictions on most streaming platforms.

Our expert colleagues at TechRadar rate Surfshark as one of the best VPNs. Not only is it great for unblocking streaming services, it has top-level security features, a reasonable price tag and, right now, a big discount.

Can I watch "Blue Planet III" in the U.S.?

Viewers in the U.S. face a three-month wait as "Blue Planet III" won't air on BBC America and AMC+ until 8 p.m. ET/PT on Saturday, Jan. 23, 2027.

The six-part David Attenborough documentary will air weekly on Saturdays, with episodes also available to stream on AMC+.

Remember, if you're from the U.K., but in the U.S. for work or on vacation, you can use a good-quality VPN to watch your usual British streaming services from anywhere.

Can I watch "Blue Planet III" in Australia?

Australian viewers will be able to watch "Blue Planet III" on Channel Nine, which has snagged the rights to the six-part Attenborough documentary.

However, an Australian premiere date has yet to be announced.

If you're just visiting Australia, you can always use a VPN to access your usual streaming services from anywhere.

"Blue Planet III" global trailer

We test and review VPN services in the context of legal recreational uses. For example: 1. Accessing a service from another country (subject to the terms and conditions of that service). 2. Protecting your online security and strengthening your online privacy when abroad. We do not support or condone the illegal or malicious use of VPN services. Consuming pirated content that is paid-for is neither endorsed nor approved by Future Publishing.

Most trickery in nature happens without a shred of awareness behind it. An orchid mantis (Hymenopus coronatus) doesn't know it looks like a flower, and a moth with eyespots on its wings has no concept of the predator it's startling. These are adaptations shaped by natural selection over countless generations, not conscious choices. But a smaller set of animal behaviors look like something else entirely — deliberate tactical, and aimed at manipulating another individual's beliefs, the same way human lies do.

Figuring out which is which turns out to be one of the trickiest questions in animal behavior research, James O'Hanlon, zoologist and science communicator, told Live Science.

In this excerpt from his new book, "Liars, Cheats and Copycats: Trickery and Deception in Nature" (Columbia University Press, 2026), O'Hanlon explores camouflage, mimicry and misdirection throughout the natural world, building toward the book's central question: Can animals tell lies?

In it, O'Hanlon examines one of the strongest candidates for an animal that deliberately lies: the fork-tailed drongo (Dicrurus adsimilis), a small African bird whose ever-changing repertoire of false alarm calls has made it a favorite subject for scientists studying tactical deception.

James O'Hanlon interview: 'You start painting pictures of squirrels twirling their mustaches': A biologist on whether animals can lie

Fork-tailed drongos are remarkable vocal mimics and can do an uncanny impression of a meerkat alarm call. The meerkats respond to it just as they would one of their own and scamper to safety. Meanwhile the drongo flies in once more to steal the meerkats' abandoned food.

They don't stop there; drongos mimic a whole range of other animals' signals, mimicking various avian neighbors like the caped glossy starling or the pied babbler. Those ever-watchful meerkats fall for the ruse once more, leaving their meals behind. Researchers have identified over fifty unique deceptive vocalizations in the drongo's arsenal.

By constantly rotating their "cry-wolf" tactics, these birds ensure their victims don't grow wise to the deception, allowing the theft to continue unabated. Yet, their cleverness isn't reserved solely for exploited meerkats.

This remarkable talent for mimicry extends to other creatures as well. Pied babblers and sociable weavers, who both forage in groups upon the earth, frequently find themselves bamboozled into fleeing their food by these false warnings. Had the legendary boy who cried wolf possessed such adaptive ingenuity, he might have successfully maintained his trickery.

It would, however, have resulted in a peculiar fable with an entirely different, perhaps darker, moral lesson.

It's early days in our understanding of whether animals can tell lies. Social group-living animals are likely candidates for finding animal tricksters in the wild, and we have only scratched the surface of what kinds of trickery goes on in these societies. Time will tell whether similar forms of deception are happening in the subsonic songs of whales and dolphins, the chemical mists of ants and termites, or the barks and howls of wild dogs.

Despite the growing list of evidence, scientists are still hesitant to conclude definitively that animals can intentionally deceive another, in a similar way to humans. This might have more to do with the professional conduct of scientists than it has to do with the reality of what goes on in animal societies.

Firstly, one of the most important rules in studying animal behaviour is to not anthropomorphise animals. In other words, don't project human-like qualities or emotions onto other species. Scientists must be completely objective and not assume that other animals think, behave or make decisions for the same reasons we do.

Since lying has always been perceived as a human behaviour, scientists are incredibly hesitant to conclude that it could be happening in other animals.

The second reason is that scientists are trained to never definitively conclude anything. There is an idea in science that you can disprove things, but never really prove things. This is why you will find scientific writing littered with phrases like "the evidence suggests," "it's probable that," or — my personal favourite — "the most parsimonious explanation is," and so on and so forth.

A professional scientist will often give a direct "No" answer but rarely a direct "Yes." It's like squeezing blood from a stone. But this is a good thing. What often sounds like indecisiveness or a lack of certainty is actually just good professional practice. It's part of a scientist's job description — to consider all possible explanations for the observations they have made and examine every possibility on its own merits.

Then the conclusions that are drawn come down to which of these possibilities is most likely. In a universe of infinite possibilities and scales of enquiry, it would take an impossible amount of overwhelming data for scientists to exclude all possibilities but one.

This article is adapted from Liars, Cheats, and Copycats: Trickery and Deception in Nature by James O’Hanlon . Copyright © James O’Hanlon 2027, 2025 First published in Australia by NewSouth, an imprint of UNSW Press Ltd. Used by arrangement with Columbia University Press. All rights reserved.

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Most deception in nature happens without much awareness from the creature involved. From a moth that has evolved to look like a hornet to orchid mantises that mimic flowers to lure in pollinators, deception is part of these animals' nature. But in his book "Liars, Cheats and Copycats: Trickery and Deception in Nature" (Columbia University Press, 2026), biologist James O'Hanlon turns to tactical deception aimed at manipulating what another animal believes — and whether we can consider this as lying.

Live Science spoke with O'Hanlon about his book, and why so many scientists are reluctant to say "yes, animals can lie."

Read an excerpt: Can animals lie? This sneaky bird might be proof.

Olivia Maule: The chapter opens with a moment from a talk you gave, where a woman at a senior citizens' club asked you a question about orchid mantises that left you stumped: "How does the mantis know to look like a flower?" Why did that moment stick with you enough to open the chapter with it?

James O'Hanlon: Because it was such a simple, straightforward question that I couldn't give a simple, straightforward answer to. At the time, I was thinking about what's going on in the brains of the animals I was looking at — does a camouflaged animal actually know it's camouflaged? Does an insect that looks like a leaf know what a leaf even is?

And it got me thinking: they don't need to. This stuff just sort of works because it works. That's a completely different type of deception to the other things dealt with in this chapter, which is: Do animals actually know that they can lie? Can they intentionally deceive, like we can?

OM: So would you say you have an answer to that question now? And if so, what would it be?

JO: If I had to answer, it would be yes. It looks like it. But scientists are paid to be pedantic, so it's always going to be a "yes, but" or a "possibly." There's a ton of behaviors that look like animals can lie, and they're really good at it, but with any type of science, we're never going to know for certain what's going on in their brains. It's a best-guess situation.

OM: How would you help readers hold those two ideas at once — that this is genuine deception in an evolutionary sense, but not necessarily lying in the way we mean it as humans?

JO: When we talk about lying in humans, there's a value judgment attached. We're judging each other on whether we're good or bad people, doing right or wrong things. We kind of have to relax that judgment a bit when we're talking about other animals.

I guess it becomes an ethical question — we look at deception as being right or wrong, morally good or bad, and that's a very human-centric way of thinking. Ethics and morals are things we've developed to help us get along in our own societies. Who knows what's going on in animal societies?

There's an example in the book of golden snub-nosed monkeys that use deceptive alarm calls to scare off other members of their group and steal their food. After a while, those monkeys start to get ignored, and the group stops responding to their calls. So maybe there is some sort of animal-society rules and regulations keeping lying in check. Maybe. We'll see.

OM: I do want to ask about the chimpanzee study, in which chimpanzees intentionally misled competitive handlers to boxes without food, and compare it to the 2017 dog study, where dogs learned to mislead handlers much faster than the chimps did. What did that result do to the assumption that big brains equal better lying?

JO: There's always been this idea that lying is a really cognitively complex task — you need the brains not just to realize what's going on in the real world but to imagine a false possibility, and then to describe that false possibility as if it were real. We talked that up as something you need big brains to do, and there was also a bit of patting ourselves on the back for being such smart animals — maybe we lie a lot because we're such smart animals. But the more we learn about animals and what they're capable of, the more we realize they can do so much more than we thought was possible with the brains they've got.

OM: Does that suggest lying is less about raw intelligence and more a byproduct of needing to survive in a group?

JO: As far as all the examples of tactical deception in the book that look like they're intentional, they all, or mostly all, come from social animals. We don't seem to see it in solitary animals. That's a big sign that maybe it's something that's evolved because individuals can exploit it in a social setting. But it's still such early days, so it's hard to say for definite how different levels of sociality, and how bonded individuals are within groups, correlate with more deception.

OM: Could you elaborate on the distinction between deception and something like the camouflage you introduce in the book with the tiger's stripes?

JO: Compared to the intentional deception we've been talking about, things like camouflage still work regardless of whether the animal doing it is aware of it or not. The idea behind lying and tactical deception is that it only works because it's intentional — there's some sort of choice to do it.

Whether the animals are aware of that choice is another question. Think about the way we do it as humans — are we always aware of it? Whenever your friend asks whether you like their new haircut and you just go, "Yeah, it's great," you don't really think about the fact that you're probably lying. It's just part of our social norms. So it becomes a very blurry gray area very quickly.

OM: It sort of boils down to the choice of it all — whether they can choose to do it or not, which raises the question of whether it's conscious or unconscious.

JO: It's tricky, because as soon as you start talking about it being a conscious decision these animals make, you start painting pictures of squirrels twirling their mustaches, giggling at how evil they are for pretending to hide nuts. And you start to think, maybe this isn't the right exact way to think about lying and deception.

OM: The drongo — a bird renowned for its ability to deceive meerkats — doesn't just have one trick, it cycles through different alarm calls and borrows calls from other bird species. Does that put it in a different category of liar than squirrels or monkeys, or is it the same trick with a different toolbox?

JO: It could just be the same trick with a different toolbox. It's essentially doing the same thing as the golden snub-nosed monkeys we were talking about before. But birds are incredible singers and have very flexible call structures, and there are tons of birds that can mimic other birds. Maybe you just pair that ability with this deception adaptation, and it looks a bit different, but it's the same kind of trick.

OM: Do you think these behaviors are inherited, or just innate characteristics of the drongos themselves?

JO: I don't know — I'd be interested to find out. The evolutionary aspect would be that the ones who can do it get more food and are better able to survive and reproduce. Whether they learn it from their parents, it's entirely possible. We know from birds in general that they learn calls from their parents and their social groups, and there are even studies showing birds will start learning calls while they're still in the egg, listening to their parents' calls. So it's entirely possible they learn this trick socially, as far as I know.

OM: In writing this book, what did you find is the best way to approach understanding animal behavior as it relates to human traits like lying or deception?

JO: I think there's still a little bit of baggage from old-school thinking, that you need bigger brains to be deceptive and tricky in this way, and there are still people who think it must be things like the higher apes and great apes that are capable of this stuff.

As soon as you start studying that in something like an invertebrate, it's really hard to get the idea out there — other scientists will come back and say, "No, that couldn't be possible, this must be some other type of behavior, or it just looks like tactical deception, but it's not." This happened with the researchers who did the work on cuttlefish that change one side of their body to look like a male and the other to look like a female — there was a lot of resistance to that idea, seemingly just because it was a cuttlefish, this little invertebrate, so it couldn't possibly be capable of such cleverness. But as far as the actual evidence goes, and what we can see, it's really no different from what we see in these big-brained mammals, so why not assume the same thing is going on?

A lot of it comes down to the culture and practice of science, and the people doing the science. We're supposed to be as objective as possible, but we're still humans, we're still animals. It takes a while for ideas to change.

OM: Is there a risk that this caution has become its own kind of bias, where we assume human specialness by default until proven otherwise?

JO: Yeah, definitely. It's important, as part of scientific practice, to be as objective as possible, and as a general rule, to not anthropomorphize. But at the same time, we're just animals too — we're just another one of the great apes. We share characteristics with lots of different animals, so it's not a huge stretch to think that what's going on in our brains is also going to be similar to what's going on in other animal brains.

It's just a question of when we apply that kind of thinking, and when it's useful or not. Something similar happened in the field of understanding pain in animals — scientists studying this were always trying not to anthropomorphize, not to assume animals experienced pain the way we did. Then, the more we understood it, it became quite clear that they probably did, and it almost became an ethical question to stop with the anti-anthropomorphizing and instead go, no, we know what pain feels like, we can say that.

We're never going to be able to see what's going on in their brains, but that doesn't excuse us from recognizing what's going on. So I think it became okay not to anthropomorphize but to recognize the similarities between humans and other animals, as opposed to always hinging on the differences between us.

OM: At the end of the chapter, you say that if you buy a scientist a few drinks, they'll eventually admit that animals can lie. I obviously can't buy you a drink over email, so I'll just ask you directly — do you think animals can lie?

JO: Yeah. I'll give a straightforward yes, because I can.

You need to get scientists out of their professional mindset, where they're trained to give the most correct answer that they can. And yes is a bit of a broad-stroke answer for a scientist when they're in professional mode, which is why you need to get them out of the lab and out to a bar or a cafe, and get them talking in human terms again.

OM: What would you say is your favorite example in the book — what are you most excited for readers to walk away with?

JO: I'll go with the cuttlefish example — the one where a male cuttlefish will put male color patterns on one side of its body and female patterns on the other, to trick other male cuttlefish. It might be my favorite because, as a young student, I worked on this particular species of cuttlefish. We were studying them, watching all of their crazy color-changing abilities, and just wondering what on earth they must be talking about, what was going on there. Then, years later, seeing the aforementioned research come out was this sort of lightbulb moment — that's what I was watching them do all along. I think that has a personal connection for me. I spent so much time looking at these creatures, being mesmerized by what they were doing, with no idea what was going on. So it was great to see scientists come in and figure it out, and answer those questions.

This interview has been condensed and edited lightly for clarity.

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You may have heard that sharks are older than trees. And yes, sharks are truly ancient, with an evolutionary lineage dating back hundreds of millions of years.

But are they really older than trees? Experts told Live Science that the answer depends on what we classify as a shark.

"It's all in the fine print," John Maisey, the curator-in-charge emeritus of fossil fish at the American Museum of Natural History in New York, told Live Science. "The takeaway is that the shark lineage within the fishes generally does go back further than trees. But it really depends on how you define what we mean by shark."

The modern sharks we see today first emerged around 195 million years ago, during the Jurassic period. Fossils of ancient sharks from this time can be traced to living lineages, namely Hexanchiformes, an order of sharks identified by their six or seven gills and single dorsal fin.

This means that modern sharks, at least, are not older than trees. Experts generally agree that trees first evolved in the Middle Devonian epoch, around 380 million to 390 million years ago. "I think it's not very controversial, when we had the first trees," Cindy Looy, a paleobotanist at the University of California, Berkeley, told Live Science.

For instance, the first true tree in the evolutionary record is considered to be Archaeopteris, an extinct genus discovered in a 385 million-year-old fossil forest near Cairo, New York. Looking at these fossils, Archaeopteris has many characteristics of trees we have today, including a tall, woody trunk; leaves; and a deep root system. Other early trees ‪—‬ such as Eospermatopteris found in ancient forests near Gilboa, New York, and Calamophyton in southwest England ‪—‬ also appeared in the fossil record 390 million and 393 million years ago, respectively.

But when we look at the extinct relatives of modern sharks, "that's where it gets a bit wobbly," Maisey said. There are fossils from the sister groups of modern sharks that can be traced back through the Permian period and into the Devonian period (around 359 million to 420 million years ago). The most abundant group are hybodonts, an extinct group of spiny fish that have a unique calcification pattern in their cartilage that is similar to that of modern sharks.

"It’s called tessellated calcified cartilage, and that's a very important hallmark of most of the shark-like fishes and their ancestors," said Maisey, who has studied a spiny fish fossil called Doliodus problematicus from the early Devonian. If this definition is used, these sharks first appeared around 400 million years ago, before trees emerged.

Sharks' rough skin can be traced even further back, with the dermal denticles — the tooth-like scales that roughen a shark's skin — first appearing in the fossil record around 450 million years ago.

These transition fossils, where fish were evolving into sharks and gaining shark-like traits, introduce a gray area in the definition of sharks. "When you get back into the ancient past, when you're not dealing with things that we have living examples to compare with anymore, then it becomes a bit more tricky [to figure out what they are]," Maisey said.

Fossils also present a very limited picture. Many contain only fragments of an animal, like a fallen tooth, so scientists are still piecing together the clues of exactly how and when sharks arose. That means every fish fossil discovery often leads to more questions about what other transition fossils could be out there, Maisey said.

There is also much to be discovered about trees, Looy added. Terrestrial fossils, especially ones that clearly show parts of a tree, are quite rare. Finding a fossil forest requires a lot of luck, she said, although there is little indication that trees were present before the Middle Devonian.

"That's why I think the fossil record is so intriguing," Maisey said. "Because it may not give us all the answers, but it certainly raises questions."

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

Lucid dreaming — in which the dreamer is aware that they are dreaming and can sometimes influence the dream's trajectory — is a skill that can be honed, a new study finds. And the researchers found that doing this is surprisingly easy, after training participants to do exactly that using virtual reality (VR) twice a week for just one month.

The study's results could have practical benefits, said Daniel Morris, a cognitive neuroscientist at Northwestern University who studies dreams and was not involved with the work. "Lucid dreaming can benefit people with nightmares by allowing them to transform their nightmares into positive dreams and feel greater agency in their dreams," Morris told Live Science in an email.

Before this study, published Sept. 28 in the journal Frontiers in Psychology, neuroscientists tried to induce lucid dreaming with various methods. These included meditation exercises and so-called reality checks, in which participants ask themselves while awake whether unusual phenomena they encounter — such as people wearing odd Halloween costumes — are real or if they're dreaming. The idea is that they will ask themselves the same question in their sleep during bizarre dreams.

However, "for most people, our day-to-day lives may not feel 'dream-like,'" Morris said, explaining why reality checks have had mixed results and don't reliably trigger lucid dreaming.

Since dream-like scenarios are rare in waking life, the neuroscientists behind the new study used VR simulations of bizarre situations to complement reality-check exercises.

The team, based at the University of Trento in Italy, recruited university students and asked them to meditate and then perform the VR training. The meditation was intended to increase students' awareness of what they were thinking about in a given moment. Each time they encountered bizarre happenings in the VR environment, such as objects or people violating laws of physics or rapid switches from one scene to another, they performed reality checks.

After the training, participants went home and were asked to keep a dream diary that they wrote in every morning. They also filled out daily questionnaires, citing the number of dreams they recalled and how many they remembered being lucid.

The participants experienced lucid dreams four times more often than participants did in a second group that did reality checks without performing any meditation or VR training. The study also included another comparison group, in which participants carried out reality checks during realistic rather than dream-like VR simulations; these participants were over eight times less likely to report lucid dreams. This latter comparison ensured that the results were not caused solely by the use of VR, the researchers said.

It was particularly surprising to find that such little training with the dream-like VR simulations was needed to develop lucid dreaming as a skill, said study co-author Nicola De Pisapia, a neuroscientist at the University of Trento. His team ran the experiment for only a month because any longer would have been too demanding for the participants, De Pisapia noted.

Study co-author Andrea Signorelli, a doctoral student in De Pisapia's lab, thinks the VR intervention is at the heart of why the approach worked. People often don't realize that they're dreaming because the dreams "fool" your senses and feel realistic in the moment, he explained.

"Virtual reality is the technology to fool you on stereoscopic vision and auditory information," he said. The term "stereoscopic" refers to techniques that create 3D illusions from 2D images by mimicking how human eyes see.

"It's basically the most immersive technology that we have at the moment," making it a good intervention for reality check exercises, Signorelli said.

The team also compared the number of lucid dreams participants reported against their total number of recalled dreams, which revealed an interesting pattern. On average, participants in each group recalled more dreams after starting the experiment than they did beforehand. However, the dream-simulating VR group recalled the fewest dreams overall after entering the experiment, even though they had the highest number of lucid dreams.

Signorelli speculated that perhaps it takes a lot of energy to have lucid dreams, which could divert resources away from recalling other dreams. Morris argued that, alternatively, participants in the lucid-dream VR group "may have been less motivated to report non-lucid dreams than the control groups." So there may have been some bias in the reporting.

The study had some limitations, such as its small sample size of 38 participants. Plus, neither of the two control groups were asked to meditate, so it is impossible to say whether the meditations or the dreamlike VR sessions had more influence over lucid dreaming in the test group.

The team is now doing a follow-up study in which the meditation part has been removed, Signorelli said, to reveal whether the VR dream scenarios are the critical factor, as suspected.

Signorelli said that he would like to see lucid-dream training tailored for each individual. For example, the VR simulations could be personalized to simulate a recurrent nightmare that a given person experiences, training them to recognize triggers specific to that dream, he said.

"Other future research could explore the potential therapeutic benefits of this intervention for people with nightmares, anxiety, or PTSD [post-traumatic stress disorder]," Morris suggested.

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

How much do you know about sleep and dreams? Find out with our sleep quiz!

When the sun inevitably dies, not even the outer solar system will be safe from the resulting chaos, new research hints.Scientists have long thought the outer solar system ‪—‬ which comprises the four giant planets Jupiter, Saturn, Uranus and Neptune — would mostly retain its present-day appearance for hundreds of billions of years to come. But a new study suggests that the outer giants may develop weirdly shaped orbits as the sun runs out of fuel, causing the planets to cross paths and destroy themselves through collisions within three billion years of the sun's transformation into a red giant.

The findings, published Sept. 21 in The Astrophysical Journal Letters, could change our understanding of what kinds of exoplanets orbit certain stars.

In about 5 billion years, the sun will balloon outward as a red giant after exhausting all of the hydrogen in its core. During this red giant phase, our star will swell to 100 times its present-day size, gobbling up Mercury, Venus and possibly even Earth in the process, Nathan Kaib, a planetary scientist at the University of Oklahoma who wasn't involved in the new research, told Live Science in an email. Following this violent swelling, the sun will crumple into a collapsed core called a white dwarf.

Until now, scientists thought the four outer planets would escape this phase relatively unscathed. A 1998 simulation-based study suggested that the gas the sun spews from its outer layers will push this planetary quartet outward, doubling the radius of each planet's orbit. Only the gravitational impact of a runaway star could destabilize this new order, and such events are thought to occur only once every billion billion years.

Solar recoil

These predictions hinged on the assumption that the sun will eject its outer layers smoothly. However, recent observations of stars suggest a jerkier loss of mass, with gas clouds lofted by plumes of plasma in the sun — as though our star were spitting out mass blobs. "They're kind of like coronal mass ejections, except much larger," Jim Fuller, a professor of theoretical astrophysics at Caltech and co-author of the new study, told Live Science in an email.

Each "blob" pushes the star backward, similar to how a fired bullet causes a gun to recoil. Although every push is small, moving the sun just a few feet per second, many pushes can, over time, impart the equivalent of an enormous kick that alters the sun's speed by several hundred feet per second. In fact, astronomers have already seen white dwarfs suffer such kicks in other star systems.

When Fuller, who studied these kicks, described them to Konstantin Batygin, a professor of planetary science at Caltech and the study's first author, Batygin "realized this would have important consequences for the evolution of our own solar system," Fuller said. That's because the kicks change the sun's gravitational pulls on everything around it.

Chaos at the edge of town

To determine how the sun's mass loss would influence the giant planets, Batygin created computer-based simulations of the sun and the outer planets. The researchers considered three scenarios: if the sun lost its mass smoothly, if it spit out distinct mass blobs during its entire time evolving as a red giant, and if the sun spewed the blobs only during its last stages. The researchers also varied each ejected blob's mass.

The first scenario produced results similar to those of previous studies, with the outer solar system retaining almost all of its features for billions of years. In contrast, the other two cases had drastically different results. Using 672 simulations, the researchers found that if the sun lost mass in blobs, the giant planets would be thrown into chaos, switching places, developing weirdly oval-shaped orbits, and even getting ejected out of the solar system entirely. Most dramatically, in 96% of the simulations with the heaviest ejected mass packets, the planets get destroyed as they crashed into each other.

These developments also happened much more rapidly — less than a few hundred million years after the sun transformed into a white dwarf, or even during the red giant phase, in the most extreme scenarios.

The study's findings hint that analogues of the present-day outer solar system around white dwarf stars are less likely to exist than previously thought. Kaib noted that the study's results suggest that planets with oval-shaped orbits should dominate instead. It's thought that habitable planets could exist around white dwarfs, but this study's findings show that our understanding of those distant star systems may be incomplete, and that such worlds may, in reality, be unstable.

See how well you know our planetary neighborhood with our solar system quiz!

While people use artificial intelligence (AI) tools to help with tasks like learning new skills or answering questions, a new study suggests that these benefits may come with a downside.

The findings, presented at the 2026 Conference on Language Modeling in San Francisco earlier this month, revealed that people who used AI assistance for reading comprehension or math problems were more likely to struggle or give up when the AI assistance was removed. The results suggest that relying too much on AI could lower people's motivations to overcome challenging situations.

In the wake of this study, Live Science recently polled its readers on whether they felt AI was making them less motivated after using it.

More than 140 readers voted in the poll, with 30% of voters picking "No, I don't use AI at all, so this situation doesn't apply to me."

"If AI were only a tool, controlled by those who use it I might give it a try," said one commenter in response. "But it isn't under control at all. It gets into your bank accounts and moves money without authorization. It encourages suicide and self-harm. It is addictive and makes people lazy. I know someone who uses it to answer questions and while it is detailed, it makes her lazier, asking one question and getting the answer without her searching for it. AI Is a danger. It should not be allowed."

Other comments reflected this sentiment, with one reader writing, "Use of all automatic aids decrease[s] attention and retention. I see it in the use of navigation devices where drivers ought to recognize routes after a couple of times. AI helps research and cuts down lengthy searches, but over use of summaries weakens critical faculties."

Other commenters questioned whether AI is the problem, or if people are just inclined to take the easy option, asking "Would you get the same results if the answers to all but a few problems were provided on separate sheet of paper?" and another writing, "I think researchers should also investigate whether shovels decrease motivation to dig holes with one's hands. AI, like a shovel, is only a tool."

Do you agree with these readers? Let us know in the comments!

Nearly 30% of U.S. adults have lied to doctors in an effort to obtain antibiotics, either by exaggerating their actual symptoms or by fabricating symptoms, the results of a new national survey suggest. Additionally, in a second survey, about one-quarter of children's caregivers reported lying about their kids' symptoms to get antibiotics on their behalf.

"As clinicians, we know that patients lie to us sometimes," Dr. Jeffrey Linder, a general internist and primary care clinician-investigator at Northwestern Medicine, wrote in a commentary about the survey findings.

However, the results are still important because the inappropriate use of antibiotics can contribute to the mounting problem of antibiotic resistance, in which bacteria build up a tolerance to the drugs designed to kill them. Recent data released by the Centers for Disease Control and Prevention (CDC) highlight the extent of the problem: In 2023, drug-resistant bacteria and fungi caused about 9.7 million infections in the U.S., up from 2.8 million in 2017. In turn, the estimated number of deaths caused by drug-resistant germs rose from 35,000 to 50,800 between the two years.

A major factor driving resistance among bacteria is the misuse of antibiotics — in other words, using antibiotics for ailments like viral infections, which the drugs do not treat. For individual patients, such prescriptions don't cure their illness and can result in an upset stomach or issues with the gut microbiome, the community of microbes in the intestines. Simultaneously, they place extra pressure on bacteria to evolve resistance, granting the germs opportunities to pick up new strategies for thwarting antibiotics.

Doctors play a big role in ensuring that the antibiotic prescriptions they write are necessary. Part of their decision-making process comes down to what patients say about their symptoms, some of which may be fabricated, the two new surveys suggest.

Motivations for lying

The new surveys were published Friday (Oct. 30) in the journal JAMA Network Open.

The first survey was completed by nearly 960 adults from across the U.S. in January and February 2026. It asked whether the respondents had ever told a healthcare provider that their symptoms were worse or more long-lasting than they were in order to get antibiotics, as well as whether they'd ever made up symptoms for the same reason. It then inquired about what motivated a given patient to lie — or avoid lying, if they were truthful — as well as posed contextual questions about their demographics, health behaviors and beliefs.

Overall, about 28% of the respondents reported misrepresenting their symptoms, including 26% who exaggerated their existing symptoms and 17% who fabricated symptoms. They most frequently lied about cold-like symptoms, such as fever, cough and sore throat. About two-thirds of these patients were at least moderately confident that their lie would motivate a clinician to prescribe them antibiotics, and 77% said the strategy worked for them at least once.

Often, patients' motivations for lying centered around feeling very sick, holding strong beliefs that antibiotics would help them recover quickly and get back to their responsibilities, and wanting control over the treatments prescribed to them. Compared with people who didn't lie, those who lied were also more likely to feel that clinicians didn't take them seriously or more likely to endorse statements suggesting that antibiotic resistance is a hoax.

"Greater antibiotic knowledge and aversion to taking antibiotics were associated with lower odds of misrepresentation," meaning lying about symptoms, the study authors noted.

Less than 30% of these patients regretted their lies or taking the antibiotics prescribed to them. Those that did express regret noted experiencing side effects, noticing that the treatment didn't help or feeling that the lying itself was morally wrong.

The second survey was much smaller; it included 236 parents and other guardians of children and teens under 18 years old. It posed similar questions but asked whether the caregivers had lied about their children's symptoms and, if so, what motivated them to lie.

About 27% reported lying about a child's symptoms to get antibiotics, with 87% of these caregivers believing that their lying worked at least once. Their reasons for lying were very similar to those expressed by the respondents in the first survey.

"These findings suggest that symptom misrepresentation may contribute to antibiotic overuse in pediatric care," the study authors concluded.

The surveys reached a diverse group of people, including a range of ages, demographics and locations within the United States; however, the respondents were not necessarily representative of the whole U.S. population, the authors noted. The prevalence of lying should therefore be seen as a tentative measure to be checked in future studies, rather than an unbiased, population-level metric, they wrote. It's also possible that not all the respondents who lied disclosed that they did so or remembered that they had done so.

Doctors are still the gatekeepers

Especially in outpatient settings, which account for most antibiotic use among U.S. patients, it can be difficult for doctors to quickly determine whether a patient needs an antibiotic.

One factor is that there's a lack of fast, surefire diagnostic tests for many bacterial infections. Outpatient appointments are also extremely short, so doctors sometimes worry about overlooking an infection that could then get worse, Julia Szymczak, a medical sociologist at the University of Utah School of Medicine, previously told Live Science. Another major factor is that clinicians can face pressure to prescribe antibiotics from their adult patients or from children's caregivers, as the new surveys reflect.

But in the face of these pressures and patients' occasional lies, Linder argues that it's still up to the clinicians to do the right thing. "While clinicians might interpret patients' symptom maximization and questions as demands for antibiotics, symptoms do not determine the indication, a diagnosis does," he wrote in the commentary.

"It does not track that approximately 80% of respondents who reported misrepresenting their symptoms obtained a prescription," he added, "unless prescribers were being willfully deceived or, more likely, just getting worn down with what they perceive as patient demand, regardless of actual clinical appropriateness."

When it comes to making decisions about individual patients, Linder argued that doctors don't necessarily need to think about the big picture of antibiotic resistance and how their patient's case fits into that global trend. Rather, providers should simply ask whether a given prescription is more likely to help or hurt that patient, he said.

"Clinicians' obligation is to act in patients' best interest," he said, "even if patients are hoping we do something different, even if patients do not like it, or even if patients lie about their symptoms."

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

Scientists in China are exploring what it would take to develop "the last AI built by humans" — a powerful, self-improving artificial intelligence (AI) system capable of creating its own successors.

In a new paper, researchers examine how approaches to recursive self-improvement (RSI) could help tackle the rising financial and computational costs of developing ever-more advanced AI models.

RSI refers to the idea that future AI models could direct their own training and development, using what they learn from each round of improvements to guide subsequent rounds of development.

This recursive feedback loop could eventually enable AI systems to develop newer, more powerful generations of models with minimal human input.

The study, which was uploaded to the preprint database arXiv Sept. 10 but has not been peer-reviewed, proposes a framework for classifying AI systems based on their self-improvement capabilities, from Level 1 (lowest) to Level 5 (highest).

At the lower levels, development remains largely human-led. As AI systems move up the scale, they become increasingly capable of identifying their weaknesses and deciding how to address them, eventually gaining the ability to make their own “meta-improvements” — improving how they improve themselves.

Is self-improving AI 'nonsense'?

Whether AI could ever achieve this level of sustained self-improvement remains an open question. Previous experiments have, however, demonstrated more limited forms of RSI.

In one study earlier this year, an AI system called A-Evolve-Training was tasked with improving the performance of a 30 billion-parameter large language model (LLM).

Over four rounds, A-Evolve-Training modestly improved the LLM's benchmark performance by testing different training techniques and using the results to change how it approached subsequent experiments.

Peter Bentley, a professor of digital biology at University College London, questioned whether such experiments offer a credible route to RSI.

"This idea that some AI is magically going to start generating better and better AIs by themselves [is] nonsense," Bentley told Live Science in an email.

Bentley pointed out that self-improving computer systems have been around for decades. Evolutionary computation and reinforcement learning, for instance, are both based on the principle of systems refining their performance over time in response to feedback.

The much greater challenge, he said, is developing AI systems capable of autonomously conducting the research needed to create more powerful successors — not to mention overcoming their dependence on human expertise and physical computing infrastructure.

"You can't 'recursively self-improve' unless you can also enhance your own training, enhance your hardware, and test it exhaustively in real world settings," Bentley added.

The challenge of true RSI

The study's authors acknowledged some of these challenges. Developing RSI-capable systems could require enormous investments in computing power, as well as human supervision to ensure successive improvements delivered meaningful gains. All of this becomes effectively redundant if the resources needed to develop and test subsequent AI models outweigh any benefits they offer, the authors noted.

Scientists would also need a reliable way to determine whether an AI system was genuinely becoming more capable over iterations, rather than exploiting weaknesses in tests used to measure its capabilities. This is a known problem in AI development, where models can achieve higher benchmark scores by exploiting testing methods or cherry-picking results.

Kayla Blomquist, an AI researcher at the University of Oxford and co-founder of the Oxford China Policy Lab, said that, while the paper doesn't provide a practical road map to RSI, it could help developers and policymakers understand the technical challenges and safety risks associated with increasingly autonomous AI systems.

She also questioned whether there would ever be a clear point at which AI became completely independent of human development. "The paper describes a gradual handover of responsibility rather than a single moment, so there may never be an obvious 'last' model built by humans," Blomquist added.

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The Vera C. Rubin Observatory has found what might be a tiny new world in the far reaches of our solar system, hidden beyond the orbit of Neptune — and it is among the largest and brightest objects ever discovered beyond Neptune.

If confirmed, the miniature world would increase the number of officially recognized solar system dwarf planets to six. Upper estimates of the object's size place it at more than half the diameter of Pluto, the largest known dwarf planet.

"My first reaction was one of excited disbelief," Matthew Holman, an astrophysicist at the Smithsonian Astrophysical Observatory and member of the Rubin team who wrote the code that helped discover the prospective dwarf planet, said in a statement. "Objects like this are very rare, so I immediately started checking whether I or the code had done something wrong."

Hidden among stars

The potential dwarf planet, designated 2026 ED138, orbits the sun at roughly 46 times the distance between Earth and the sun. The potential new planetoid has been hiding behind galactic camouflage; with its orbit tilted at a 25-degree angle from the solar system plane, it's at just the right angle to get lost in the light from the inner Milky Way, the researchers said.

Many telescopes struggle to see past the millions of stars making up our galaxy's bulge. The Vera C. Rubin Observatory, however, images the entire southern sky every few nights with the largest digital camera ever built, sending out millions of nightly alerts for every object that has changed brightness or position. This makes it exceptional at identifying anything that moves, from solar system objects to transient events like supernova explosions.

The observatory had only just begun its 10-year mission of scanning the sky in July, and ED138 stood out in the data.

Holman works on the software algorithms that process the extreme amounts of data the observatory collects. The code he developed with his colleague, Kevin Napier, compares billions of observations to determine which ones are detections of the same moving object. Running data from Rubin through the code revealed the unusually large object.

By looking at past data from Rubin and archival images from the Dark Energy Camera mounted on the Victor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory (both in Chile), the team was able to map out ED138's orbit over the past 10 years.

Going beyond Neptune

The Kuiper Belt is a region of the solar system beyond Neptune that is a wild frontier of small, mostly icy bodies made from frozen methane, ammonia, water and rock. It ranges from roughly 30 to 50 times the distance between Earth and the sun, and is home to most of the known dwarf planets, including Pluto. Thousands of Kuiper Belt objects have already been discovered. These space rocks can be frozen time capsules that hold clues about the early solar system's formation.

Dwarf planets are the largest Kuiper Belt objects that we know of. Bigger than asteroids but not quite planets, dwarf planets are big enough to be rounded under the force of their own gravity but too small to clear their orbits like planets do. While the International Astronomical Union (IAU) has officially confirmed five dwarf planets — Pluto, Ceres, Eris, Haumea and Makemake — astronomers studying dwarf planets often recognize at least nine, with several more candidates whose properties are still unknown.

Depending on which astronomer you ask, there could be anywhere from a handful to hundreds of dwarf planets in this part of the solar system. Identifying which Kuiper Belt objects are dwarf planets is tricky because they are often very dim and move very slowly from Earth's perspective, since their orbits are so large and distant. The likeliest candidates have high albedo (surface reflectivity) and diameters greater than roughly 370 to 500 miles (600 to 800 km).

What makes ED138 special is its size, inferred from its brightness, albedo and distance from the sun. It's estimated to have a diameter between 370 to 930 miles (600 to 1,500 km). For comparison, Pluto — the largest dwarf planet recognized by the IAU — is 1,477 miles (2,377 km) in diameter. Ceres, the smallest IAU-recognized dwarf planet, is 595 miles (958 km) in diameter. Future observations of ED138 will give researchers a more accurate idea of its diameter and density to determine if it's round enough to join the dwarf planet club.

"If confirmed as a dwarf planet, ED138 would join a very small family of worlds," Holman said in the statement. "Rubin will image the whole southern sky again and again for ten years, so any others hiding in the places earlier surveys skipped are now within reach."

On the last day of an ecology field trip to Virginia's Eastern Shore, a biology undergraduate student discovered more than she expected. While searching for shark teeth, Brooklyn Rolph, a student at Mary Baldwin University in Virginia, stumbled upon a stone spearpoint estimated to be around 4,500 years old.

"Wow, this is so crazy," Rolph said in a statement. Already primed to look for pointy objects underwater, Rolph found a stone spear and immediately alerted the professors running the trip. "They were ecstatic," she recalled.

The stone artifact is about 6 inches (15 centimeters) long and, according to local archaeologists, a type known as a Lehigh/Koens-Crispin point. This kind of stone tool was made by Indigenous people across the East Coast of the U.S. from around 4,500 to 3,000 years ago. Sometimes called a "broadspear," the stone point also may have been used as a knife by prehistoric hunter-gatherers in the Late Archaic period.

The field trip was part of an ecology course led by Mary Baldwin University faculty members who had secured a permit from the state to explore the barrier islands off the Eastern Shore, the southern part of the Delmarva Peninsula that includes most of Delaware and parts of Virginia and Maryland.

Just after a lunch break on Sept. 21, the last day of the excursion that aimed to let students study plants and animals in the coastal ecosystem, Rolph set out to quickly explore a mound of shells on the island and noticed the spearpoint at the edge of an inlet. Her professors were blown away by the lucky discovery.

"The set of circumstances that came together that made this possible is quite unbelievable," Paul Callo, a biology professor at Mary Baldwin University who was co-leading the trip, said in the statement. "The tide was coming in, so the spear point was soon to be buried."

When Rolph showed Callo the artifact, he was "truly at a loss for words," he said. "It is certainly awe-inspiring to see and touch something that was made by human hands thousands of years ago."

The barrier island where Rolph found the stone point is part of a natural area owned by the Virginia Department of Conservation and Recreation, which means the artifact is now the property of the Commonwealth of Virginia. Archaeologists collected it from the Mary Baldwin group and have taken it to the Virginia Department of Historic Resources for further study.

Rolph was fine with not keeping the spearpoint. "That's how you get cursed!" she said.

How much do you know about the first people to reach the Americas? Find out with our First Americans quiz!

Researchers have virtually reconstructed the face of a man who was decapitated after his death almost 2,000 years ago and then buried near a Roman military fort in Scotland.

While it's unclear why the man was beheaded, other burials hundreds of miles away may offer a clue. A chemical analysis of the man's remains suggests that he grew up in southern Britain. Beheading bodies may have been an obscure burial rite for some southern Britons, as other decapitated bodies from about the same time have been found in that region, John H. Reid, an archaeologist at the Trimontium Trust who was not involved in the excavations, told Live Science.

Another mystery is why a southern Briton was on the Roman frontier, but it seems that he was working for the Roman army when he died, researchers at National Museums Scotland said in a statement. However, his skeleton shows the man's right arm had such limited movement that he could not have used a sword, so he was probably not a soldier, they added.

Despite this disability, however, it's possible that the man used weapons in his other hand, or had a job in the Roman army that did not require frontline fighting, such as a clerk.

"He could have been left-handed, or he could have had a 'desk job'," said Reid, who is the author of the book "The Eagle and the Bear: A New History of Roman Scotland" (Birlinn, 2023).

The man was probably about 50 years old when he died between A.D. 142 and 165. His remains were then buried near the Roman fort at Inveresk, on Scotland's east coast just southeast of what's now Edinburgh, according to the statement.

An analysis of the man's skeleton indicated that he had lived an active life. His nose had been broken and healed, and his right elbow showed extensive bone growth, perhaps from arthritis. Reid said the bone growth may have been his body's response to a physical injury.

Researchers at National Museums Scotland and the independent U.K.-based forensic anthropologist Christopher Rynn created the facial construction based on the man's skull.

Romans in Scotland

The Roman fort at Inveresk was built around A.D. 140 and acted as a command-and-supply center for Roman forts along the Antonine Wall, which ran along the shortest route between Scotland's west coast and east coast — roughly the line between Glasgow and Edinburgh, although neither city existed at the time.

The Romans had hoped to secure all of Scotland under their rule after their invasion of Britain under Emperor Claudius in A.D. 43. They tried to impose control after their victory against a coalition of native Caledonian tribes at the Battle of Mons Graupius (possibly near the Scottish city of Perth) in about 83. But by about 120, the Romans had retreated to the heavily fortified line of Hadrian's Wall, near the modern border of England and Scotland.

The fort at Inveresk was built for a second push that aimed to secure Roman control over southern Scotland by establishing the Antonine Wall. But this failed too, and after A.D. 162, the Romans withdrew again to Hadrian's Wall, until the final collapse of Roman rule in Britain in the early fifth century.

Strange burial

Reid told Live Science that Scotland's soil seldom preserved human skeletons, making the discovery of a Roman-era burial an uncommon find. Although the man had been decapitated after his death, other aspects of his grave indicated he was buried with dignity. In other words, his burial was unlike those of executed criminals, who were often decapitated in Roman-era Britain, he said.

The remains from six Roman-era burials have been found at Inveresk, and four of the dead had been similarly beheaded, the statement said.

There are several ways non-Romans could have served with the Roman army, Reid told Live Science. They might have been employed as servants or artisans attached to the Roman legions, or they might have been soldiers in Roman auxiliary units or even citizen-based legions, he said. By the time of the Antonine Wall, few members of the Roman army in Scotland would have been from the Italian peninsula, he added.

The chemical analysis looked at the ratios of isotopes, or variations of chemical elements, in the man's remains. This analysis suggested that the man had grown up in southern Britain. Alternatively, he may have been recruited from a nearby region, such as the coast of what's now the Netherlands, that gave the same isotopic profile, Reid said.

Reid and his colleagues have found extensive evidence of the Roman army at the Burnswark site in southern Scotland, including the deadly whistling sling bullets they used against their "barbarian" foes. Archaeological work there is ongoing.

What do you know about the Empire's conquest of the British Isles? Find out with our Roman Britain quiz!

Deep in a limestone cave on Turkey's Mediterranean coast, two very different sets of humans left behind nearly identical traces of their lives — similar stone tools, the remains of the same prey animals, the same types of seashells pierced and strung into ornaments. They may have been separated by thousands of years and may not have directly interacted. Yet the overlap between them was striking enough that researchers studying the site had to look twice.

The site, Üçağızlı II, offers one of the clearest examples of a conundrum that scientists have long wrestled with: Neanderthals and modern humans (Homo sapiens) didn't just collide and go their separate ways. They inhabited the same areas, and, as dozens of genetic studies have confirmed, had sex, across tens of thousands of years and on multiple continents. The DNA of nearly every person alive outside Africa today carries the proof: Roughly 2% of the non-African genome is Neanderthal.

And yet, there is not a single archaeological site that shows them living together. Knowing that modern humans and Neanderthals mated is not the same as understanding how it happened. Who approached whom? Were these interactions consensual? Were they the result of violence or trade alliances? Who raised these hybrid babies? And what does the genetic record tell us about the social lives of two different kinds of humans navigating each other's existence for the first time?

Some of the answers, it turns out, are written on the X chromosome — and they are stranger than expected.

A puzzle on the X chromosome

The first high-coverage Neanderthal genome was sequenced in 2010, and for the next 15 years, researchers kept noticing something puzzling: Neanderthal DNA was less common from the X chromosomes in people alive today.

One of the two sex chromosomes in humans, the X chromosome represents about 5% of the DNA in cells. Most females carry a pair of X chromosomes in each cell, while most males have one X and one Y.

Everywhere else in our genome, traces of long-ago breeding between Neanderthals and modern humans showed up in roughly consistent proportions. But on the X chromosome, there was far less Neanderthal DNA.

The leading explanation was negative selection — the idea that Neanderthal gene variants unique to the X chromosome were somehow incompatible with modern-human biology and had been gradually eliminated from the gene pool over thousands of generations. It was a reasonable hypothesis, given that incompatibilities elsewhere in the genome did lead to the weeding out of Neanderthal DNA on other chromosomes over time.

To understand why the negative selection explanation didn't explain the X chromosome data, however, it helps to know what different parts of the genome actually do. Some stretches of DNA are protein-coding regions; they contain the instructions for building proteins, the molecular machinery that does most of the work inside cells. Others are regulatory sequences that don't build proteins themselves but help control when and how much of a protein gets produced. And then there are still other stretches of DNA that don’t appear to code for proteins or directly regulate gene expression, though researchers suspect at least some have functions we don’t yet fully understand.

Alexander Platt, an evolutionary biologist at the University of Pennsylvania's Perelman School of Medicine, hypothesized that if the problem was that Neanderthal gene variants on the X chromosome were inherently harmful, modern-human X gene variants would have been advantageous in Neanderthals. As a result, X chromosomal DNA extracted from Neanderthal skeletons should show an excess of modern-human DNA in stretches of the genome where they'd provide measurable benefit. They reasoned that this excess would likely appear in protein-coding genes or the regulatory regions that control their expression, not noncoding DNA.

But that's not what they found. Instead, Neanderthal X chromosomes carried more modern-human DNA in the noncoding regions of the genome than in coding regions. This pattern didn't reflect selection for better gene variants. It was a signature of reproduction ‪—‬ a record of who was passing chromosomes to whom.

In a typical pregnancy, the mother contributes an X chromosome via the egg, and the father contributes either an X or a Y via the sperm cell. So, while an individual is guaranteed to inherit their mother's X, they don't necessarily carry their father's — males exclusively inherit their mother's X. That pattern differs from the other 22 pairs of chromosomes, which mothers and fathers contribute to equally. Across a population, then, two-thirds of X chromosomes are inherited from mothers and one-third from fathers.

This fact makes the X chromosome a particularly sensitive recorder of who was reproducing with whom.

Long-standing sexual preference

Tracking the flow of X chromosomes can reveal trends in Neanderthal-human mating. If Neanderthal males paired with modern-human females more often than Neanderthal females paired with modern-human males, you'd see more modern-human X chromosomes flow into the Neanderthal gene pool.

When the team ran simulations to explore this idea, the data suggested what Platt described as a persistent, recurring mating preference: Males with more Neanderthal ancestry tended to reproduce with females with more modern-human ancestry. And this trend held across at least two distinct mating periods separated by around 200,000 years, said Platt.

This finding gave the researchers a new window into the timeline of mating between Neanderthals and modern humans. Platt's team identified at least two distinct pulses: one roughly 45,000 years ago, which produced the majority the Neanderthal DNA that lives on in non-African genomes today, and an earlier period over 200,000 years ago, whose genetic traces survived not in modern-human populations but in Neanderthals.

The pattern of Neanderthal males having offspring with H. sapiens females appears in both periods, separated by more than 150,000 years.

What the X chromosome data alone cannot say is why the pattern exists. It documents who reproduced with whom. It says nothing about who wanted whom.

Biological incompatibility

That distinction matters, because the same genetic signature can emerge from very different causes, and some have nothing to do with sexual preference.

Rajiv McCoy, a geneticist at Johns Hopkins University, pointed out that biology alone could produce a genetic signal like this one. When closely related species interbreed, the success of a pregnancy can depend not just on whose genes are inherited but on which parent belongs to which group.

Even if Neanderthal genes work fine in a modern-human genetic background, hybrid pregnancies may simply have been more likely to succeed when the Neanderthal was the father rather than the mother. That's not because of either parent's sexual preferences, but because of how their respective biologies interacted in the womb, McCoy told Live Science.

Researchers have recently proposed a few mechanisms that fit neatly with this theory. One study suggests that Neanderthal red blood cells restricted fetuses' growth in the womb. Another proposed that Neanderthal mothers carrying hybrid offspring may have been more prone to preeclampsia, a life-threatening pregnancy complication. Nothing in the existing data definitively rules such causes, McCoy said.

In practice, the two explanations are hard to separate. "Our models have no way of distinguishing mating from mating that produces a viable and fertile offspring," McCoy said. If hybrid pregnancies failed more often when the mother was Neanderthal, the genetic record would look similar to a world where Neanderthal females mated less often with H. sapiens males. Sexual encounters that didn't result in offspring left no genetic trace.

For now, the question of what drove that bias — social preference, or biology — remains open. Whatever barriers existed between the groups, they clearly weren't absolute. Multiple distinct episodes of interbreeding over thousands of years, McCoy noted, is itself evidence that the fertility of hybrid individuals was "sufficiently intact to leave a lasting mark."

How Neanderthal and human groups interacted

Bridget Alex, a researcher in human evolutionary biology at Harvard University who has spent her career reconstructing the timing and geography of Neanderthal-H. sapiens overlap, cautioned that all this is hampered by one fact: no direct archaeological evidence reveals how the two groups interacted.

"Despite a century and a half of Neanderthal research," she told Live Science, "no one's ever found a Neanderthal and Homo sapiens fossil in the same exact layer dated to the same exact period at the same exact site."

Instead, we have a regional and variable patchwork shaped by conditions that shifted over thousands of years and hundreds to thousands of miles.

Neanderthals inhabited a territory stretching from Siberia to Iberia to Southwest Asia between roughly 250,000 and 40,000 years ago. Modern humans were evolving in Africa during much of that span and came out repeatedly, in multiple waves, meeting Neanderthals in different times and places, with likely very different outcomes each time, Alex said.

"It's not like the Neanderthals living in what's now Spain could call up the ones in what's now Uzbekistan and be like, 'OK, what's our policy with modern humans? Do we kill them, have sex with them, ignore them?'" she said. "My assumption has always been that interactions would vary across time and space depending on the particular environmental conditions, social conditions, and just the whims of a particular group."

At Grotte Mandrin, a cave in the Rhône Valley in southern France, archaeologists found one of the most illuminating records of what those encounters may have looked like. Ludovic Slimak, a paleoanthropologist at the University of Toulouse who has spent years excavating the site, described it as something genetics alone can't offer: "an extraordinarily precise archaeological sequence of Neanderthals and [Homo] sapiens occupying exactly the same place," he told Live Science in an email.

Neanderthal artifacts fill layer after layer of radiocarbon and luminescence dating up to about 57,000 years ago. And then, in one thin layer dated to between 56,800 and 51,700 years ago, there's a set of different stone tools and a single tooth that appear to belong to H. sapiens. Then, in layers immediately above, beginning around 51,700 years ago, Neanderthal artifacts appear again. That group of modern humans arrived, lived briefly in a continent otherwise inhabited entirely by Neanderthals, and then disappeared.

"What strikes me most is not mixture but proximity without fusion," Slimak told Live Science in an email. In other words, the two groups left no trace of cultural exchange or shared practice.There were "two human populations occupying the same landscape, probably encountering one another, while remaining culturally and biologically very different," Slimak said.

Genetics also paints a portrait of two very different social architectures. Two sites exemplify the trends: At Sunghir, a burial site in Russia dating to around 34,000 years ago, two H. sapiens adolescents were interred head to head beneath thousands of ivory beads and mammoth-bone spears. Ancient DNA analysis showed they were not immediate family members, yet they were buried together in an elaborate ceremony that implies a social world much wider than their immediate group.

In contrast, at Chagyrskaya, a cave site in Siberia, Neanderthals buried in what appears to be a single community layer included a father and his teenage daughter, and a second pair of individuals who shared roughly a quarter of their DNA.

While these are just two sites, they reflect a broader trend that shows up repeatedly in genetic data: Human groups tended to operate through what Alex described as a nested structure: Tens of thousands of years ago, small groups of perhaps 20 or 30 individuals maintained broader ties through ceremonies, intermarriage between human groups and exchange with other groups.

In contrast, data from Neanderthal sites reveal that they tended to cluster in small, tightly knit groups that remained relatively separate from other Neanderthal populations.

Unlike modern humans, Neanderthals didn't regularly mate with individuals in other communities, Alex said. The result, written in their genomes, is that individuals within a single Neanderthal group were often closely related. Their genomes show low genetic diversity across the board, — "kind of suggesting they're always a population on the verge," Alex said, "like an endangered species."

Still, there had to be some out-group mating. At sites where researchers have extracted genomes from several Neanderthal individuals, the pattern is consistent: Male Neanderthals were more closely related to each other than female Neanderthals were to each other. Females, by contrast, seemed more likely to have come from elsewhere. This is the signature of a "patrilocal" social structure in which males stay in their birth groups and females move between them.

Neanderthals' insularity sharpens a key question: If Neanderthal groups weren't regularly folding in Neanderthal females from distant communities, they would probably be even less likely to incorporate female H. sapiens. So how did modern-human women end up producing offspring with Neanderthal men at all?

A numbers problem

Fernando Villanea, a population geneticist at the University of Colorado Boulder, thinks the question may be framed backward. The image of Neanderthal males raising hybrid children with modern-human females within Neanderthal communities, he argues, probably inverts what actually happened.

Something the genomes of late Neanderthals — those living toward the end of their long history in Eurasia — make clear is that they were roughly 10 times more inbred than the modern human ancestors who were then expanding out of Africa in large numbers, he noted. That level of inbreeding isn't usually a choice; it reflects how small and fragmented Neanderthal populations likely were.

Archaeological and paleoclimatic data fill in the context: The ecosystems Neanderthals were best adapted to were shrinking as the planet entered a warmer, more humid period. Modern humans, who had evolved in hotter, wetter African environments, were simply better suited to Europe's new conditions, experts think.

The resulting numerical imbalance changes how scientists think about mating between Neanderthals and modern humans.

"We need to imagine scenarios where a majority of modern human groups traveling into Eurasia are encountering a vanishing minority of Neanderthals," Villanea told Live Science.

In the crucial period between roughly 50,000 and 44,000 years ago, when much of the interbreeding that left a trace in our DNA took place, Neanderthal DNA made up 5% of the modern human genome. Given how heavily humans outnumbered Neanderthals at the time, "that's a lot of matings occurring between the two." The most likely story, Villanea proposes, is "human groups absorbing surviving Neanderthal individuals and raising their children in a mostly human group."

His 2018 study in the journal Nature Ecology & Evolution established that this happened across multiple distinct episodes — and the later ones are particularly telling. Some ancient H. sapiens genomes from Europe around 40,000 years ago, according to the study, carry Neanderthal ancestry from individuals who lived just a few generations after archaeologists can no longer find any physical trace of Neanderthals in the region at all.

Even the very last Neanderthal survivors were still contributing to the H. sapiens gene pool. A 2024 study by Leonardo Iasi and colleagues similarly determined that almost 90% of total Neanderthal ancestry in humans today came from a main pulse roughly 50,000 to 45,000 years ago, likely in the Middle East, with the rest trickling in from more sporadic encounters scattered across Eurasia.

That paints a picture of meetings becoming rarer and rarer as Neanderthals disappeared, with hybridization continuing whenever they did meet up. "This, to me, says deliberate integration of Neanderthal individuals into human groups," Villanea said.

The cost of being hybrid

We know that some hybrid Neanderthal-H. sapiens survived because "we still carry the legacy of their existence," Alex said. However, we know they didn't thrive, because the Neanderthal ancestry of our ancestral populations eroded quickly.

Most genes work in concert with other genes across the genome. When Neanderthal-specific variants entered the modern-human genome, it was like trying to put gears from one machine into a slightly different one; the parts didn't quite fit together. As a result, natural selection removed the Neanderthal variants rapidly. Villanea's calculations, based on the rate at which chromosomes recombine during cell division, suggest the drop from the original approximately 5% Neanderthal DNA roughly 50,000 to 45,000 years ago to the roughly 2% carried today happened in around 10 human generations.

"That's very fast," he said. "In real-life terms, that means a lot of hybrids did not survive to reproduce, and the ones that did probably had to deal with life-long health problems."

Platt's team looked at genetic evidence from multiple sites across Eurasia and found that the genetic purge ran in the opposite direction, too. Modern-human DNA was also being selected out of Neanderthal genomes.

Neither had inherently superior genes, Platt concluded. The gene variants were simply optimized for the separate evolutionary histories of their respective lineages, hundreds of thousands of years of independent adaptation that made certain combinations disadvantageous, if not fatal.

Where the hybrids ended up

If Neanderthal males and modern-human females really were producing more surviving offspring than the reverse pairing, where did those children end up?

Villanea was cautious about reading too much into the X chromosome pattern on its own to answer that question. The imbalance Platt found is real, he said — not a statistical quirk. But "there is nothing in the X chromosome data that says it's based on human or Neanderthal mating preference," as Platt proposes.

The same pattern could, in theory, emerge from Neanderthal males leaving their birth groups to find mates, but as archaeological evidence suggests, this was not typical behavior. More likely, he argues, is something biological.

In Peromyscus maniculatus and Peromyscus polionotus — two closely related species of North American deer mouse — a phenomenon called genomic imprinting causes hybrid offspring to develop differently in the womb depending on which species was the father and which was the mother. This pattern has nothing to do with behavior or preference. A similar process in early humans could have made Neanderthal father-H. sapiens mother pairings more likely to produce surviving offspring than the reverse, without either group consciously choosing anything.

"We simply don't know enough yet," Villanea said.

Distinguishing between these explanations — social behavior versus biological incompatibility — will require more Neanderthal genomes from the critical period of contact, ideally spanning multiple geographic regions, experts said.

There's another clue in genetic evidence from a 2026 study of 27 late Neanderthals who lived between 50,000 and 40,000 years ago in what is now Belgium and France. None of those individuals showed any sign of recent ancestry from modern humans, even as H. sapiens from the same era demonstrably carried Neanderthal DNA.

If hybrid children had been raised in Neanderthal groups and went on to reproduce there, those groups' genomes should retain traces of those events ‪—‬ but they don't.

As for whether modern-human groups were patrilocal — with males staying, females moving — the answer is considerably more variable than in Neanderthals. Modern-human communities across cultures show a range of patterns, with both sexes leaving their birth groups depending on circumstance, Alex said. That flexibility may have been part of what made human groups better able to absorb outside individuals.

What we still don't know

Neither genetics nor archaeology has yet been able to answer the question at the center of this story: whether these encounters were by choice, by circumstance, or by force. Platt's team set it aside deliberately, and Alex is careful about it, too.

"We still wouldn't know if it was consensual or coerced," she said.

It's worth being specific about what different scenarios would look like archaeologically. If Neanderthal and modern-human individuals mingled through peaceful alliances, we might expect to find toolmaking techniques or symbolic objects crossing between groups at contact sites — precisely the kind of evidence that is absent at Grotte Mandrin, where, as Slimak noted, the two groups' technical traditions remained entirely distinct.

Slimak, writing from Grotte Mandrin in the middle of his excavation season, urged even more restraint. The genetic data, he said, are "consistent with an asymmetry" — gene flow moved more successfully through Neanderthal males and H. sapiens females than the reverse — but that is where the certainty ends.

The data says nothing about culture, desire, attraction or intent. "That entire social world has been added afterwards," he said.

The same signal, he pointed out, could emerge from a variety of histories — female mobility, demographic imbalance, alliance, exchange, capture, differential survival among hybrids. And these factors could contribute alone or in combination. Even the categories available for describing female movement may be too blunt. A single instance of migration, in traditional societies, can involve marriage, family strategy, alliance, obligation and violence all at once, in combinations that leave no trace for archaeology to disentangle.

"We may identify that a woman came from elsewhere," Slimak said. "We cannot recover her consent."

However, the convergence of genetics, demography and archaeology does reveal a structural picture, if not a sociological one.

The interbreeding was directional and repeated, patterned in ways that map onto the social organization of both groups — and driven in large part, Villanea's model suggests, by the sheer demographic weight of a growing human population folding in what remained of a disappearing one. Neanderthal males, in dwindling and insular communities, appear to have been the ones whose genes crossed into the larger H. sapiens world. Their children, in all likelihood, were raised as humans.

"Genes do not preserve past loves," Slimak said. "They preserve what was transmitted. And between transmission and lived experience lies almost the whole of human society."

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Scientists are getting a new glimpse of how the first galaxies came to be. In a stunning new simulation, researchers charted the aftermath of the universe's "dark age," including the appearance of the first galaxies that began to shine about 380,000 years after the Big Bang.

Lumina, the program behind the simulation, catalogs 2 billion years of cosmic time and represents a decent chunk of the 13.8 billion-year-old history of our universe. The results were published Monday (Oct. 26) in the journal Monthly Notices of the Royal Astronomical Society.

"Other simulations cannot zoom in as far as this," study co-author Mark Vogelsberger, a professor of physics at MIT, said in a statement. "The difference between the smallest and largest scales that we simulate is larger than in any other simulation."

A video published alongside the paper shows what the scientists saw. The team zoomed in on an area roughly 1.6 billion light-years wide to learn more about how the ingredients of space create galaxies.

Lighting up the Cosmic Dark Age

In the earliest years of our universe, a fog of neutral hydrogen atoms gradually built up, blocking out the light of the first stars. The hydrogen served as a "shroud" and didn't make light visible until galaxies began to form. This ancient, enshrouded period is known as the Cosmic Dark Age.

The video begins in the middle of this epoch, at roughly 45 million years after the Big Bang. Zooming in on one small part of the simulated universe, it slowly reveals a gassy halo giving way to young galaxies shining brightly within it. Included in the calculations are dark matter, stars, gas and radiation — all contributing to the reemergence of cosmic light.

"We see this is where the first galaxies form," first author Oliver Zier, a former postdoctoral researcher and computational astrophysicist at MIT who is now at Harvard University, said in the statement. "And the first stars form in those first galaxies. Those stars then create radiation. The simulation then tracks that radiation, and we can zoom way out to see how that radiation travels out from stars, through the universe, until at some point it ionizes some neutral hydrogen."

Lumina aims to show off two phenomena key to the young universe's history: hydrogen reionization and helium reionization — a first for a program of its kind. Reionization describes how the intergalactic medium, or the area between galaxies, changed from neutral hydrogen to negatively charged ions.

Hydrogen reionization took place when ultraviolet light from young stars and galaxies hit the hydrogen, removing negatively charged electrons from the hydrogen molecules — a process that also allowed light to shine through the fog. Helium reionization happened when supermassive black holes, which have a lot of energy, broke apart neutral helium molecules.

The team said the simulation could eventually be used to validate telescope observations of the early universe, especially those focused on mapping many galaxies at the same time.

Colorectal cancer rates have been rising in people under 50 since the mid-1990s. These early-onset cancers tend to be more aggressive and resistant to treatment than cancers in older adults — and now, scientists may be learning why.

A new study published Thursday (Oct. 29) in the journal Nature Medicine compared colorectal tumors from people between 29 and over 90 years old, and it revealed key differences between young and old patients.

The new findings might, in turn, help scientists uncover new ways to fight colorectal cancer in young people, said study co-author Ana Anderson, a professor of neurology at Harvard Medical School and a core faculty member of the Gene Lay Institute of Immunology and Inflammation at Brigham and Women's Hospital.

"I believe that our study is essentially a turning point now in the field," Anderson told Live Science. "Because up until now, we've had more questions than answers."

Many questions surround early-onset colorectal cancer, as the disease is rising in people under 50 even as it falls in older populations. It's now the leading cause of cancer death in the U.S. for people under 50, and its numbers are even on the rise among children and adolescents.

Beyond questions about what's driving this uptick in cases, another mystery has been why this disease is so deadly in young people.

"The clinical data suggests that the disease in the younger patients is more aggressive overall," Anderson said. "The patients, being very healthy otherwise, do not do well with treatment."

To investigate that mystery, Anderson collaborated with Dr. Kimmie Ng, an oncologist at the Dana-Farber Cancer Institute, and Dr. Ramnik Xavier, a gastroenterologist at the Broad Institute and Mass General Brigham. They used a method of analyzing RNA in cells that allowed them to work with frozen and banked tumor tissue. RNA, a cousin of DNA, reflects the genes that are active in cells. In all, the team analyzed 189 tumors: 54 from patients under 50 and 135 from patients over 50.

With that many samples, the researchers could look at gradual differences tied to each age group, instead of just comparing tumors between the younger and older groups overall. That enabled them to pinpoint subtle differences, Anderson said.

For starters, younger people had a higher proportion of connective tissue cells in their tumors than they did of malignant cancer cells. That pattern was flipped in patients of older ages. Having a smaller proportion of malignant cells might sound good, but connective tissue in tumors can secrete compounds that suppress the immune system, Anderson said. That helps protect the tumor from immune cells that might otherwise target its cells for destruction.

These connective tissue cells can also physically block chemotherapy drugs from getting to the cancerous cells. This could be one reason younger patients' cancers resist treatment, the researchers suggested.

Based on patterns of gene activity in the tumors, the researchers suspect that younger patients' cancer cells also show distinct activity related to cell-to-cell communication. That may help the cells migrate through the body more easily than cancer cells in older patients do. In other cancers, this kind of gene activity has been linked to more aggressive tumors and a greater chance that the disease will spread, or metastasize, Anderson said.

The study's results also turned up an intriguing mystery: the presence of lots of long noncoding RNA. These strands of RNA contain more than 200 building blocks, called nucleotides, that don't provide instructions for building proteins. Coding RNA, in contrast, is ferried to protein-building factories in cells to be used as blueprints.

Scientists don't know what much of this long noncoding RNA does in the body, nor do they understand what it is doing in the tumors specifically. However, they hope to find out.

Anderson and her team are already working on manipulating the RNA they found inside cancer cells in petri dishes. In time, this line of research could supply another piece of the puzzle, helping scientists understand why colorectal cancer is so aggressive in young people.

"It's a new avenue for research into this disease that we previously had no idea about," Anderson said.

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

Archaeologists have recovered a well-preserved bronze sword from a volcanic lake in Italy. The 3,300-year-old weapon may have been deposited in the lake as an offering to a deity or for a high-status warrior who lived long before the rise of the Etruscans or the Romans.

The sword was found in Lake Mezzano, which is located in the crater of an ancient volcano roughly 60 miles (100 kilometers) northwest of Rome, according to a translated statement from the Superintendence of Archaeology, Fine Arts and Landscape for the Province of Viterbo and Southern Etruria. Dating to the Late Bronze Age (14th to 13th centuries B.C.), the sword has maintained its sharp edge. It is the third such sword found in Lake Mezzano in the past 50 years.

Bronze Age people erected pile dwellings or stilt houses in what is now Lake Mezzano, and archaeologists recovered parts of the submerged settlement during their recent investigations. According to the statement, researchers also found numerous intact vases, axes, arrowheads, daggers, spearheads, pins and a bronze razor.

The sword and the razor were found near each other, suggesting the two artifacts may have been linked to a person of high social status, such as an elite warrior. But the placement of the metal weapons in a lake may also be related to a wider Bronze Age ritual practice where hoards of jewelry and bent or ritually "killed" artifacts were tossed into bodies of water. This practice continued through the centuries into Etruscan times, when wells were ritually "closed" with artifacts and human sacrifices.

During the 13th century B.C., people in central Italy engaged in trade networks that spanned the Mediterranean. "In this context, bronze weapons were not only instruments of combat, but also symbols of prestige, identity, and power," according to the statement.

The sword and other artifacts discovered in Lake Mezzano are giving archaeologists new information about the people who flourished in prehistoric Italy long before the Romans and Etruscans. Additional research is planned in the coming years, according to the statement.

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

A new U.S. intelligence agency report has seemingly released the first clear photograph of China's mysterious "dragon" space plane in orbit around Earth. The surprise snap reveals that the top-secret vehicle is very similar to its American counterpart and provides new clues about its capabilities.

The image is widely believed to show China's secretive Shenlong, or "divine dragon," space plane, which has been in action for just over six years. During this time, the reusable winged spacecraft has repeatedly made headlines after deploying various unidentified objects in low Earth orbit (LEO). As a result, government officials, private companies and individual researchers have closely monitored the vehicle using tools such as ground-based radar.

Until now, the only direct images of the space plane have been blurry snaps of light reflecting off the uncrewed vehicle toward Earth's surface — offering no clear clues to its specific design, capabilities or intended purpose. China has also never publicly shared any photos of the vehicle or revealed any key information about its design.

On Monday (Oct. 26), the Defense Intelligence Agency (DIA) released the latest version of its "Challenges to Security in Space" report, which assesses the various factors that pose a risk to American space assets. Deep within the 130-page document (on page 53), the authors included a previously unseen image of a "PRC [People's Republic of China] Spaceplane." The image's brief caption revealed that the photo had been taken in 2024 by a satellite belonging to the private space company Maxar Technologies, now known as Vantor.

The surprise inclusion of the photo was spotted and shared on the social platform X by journalist Andrew Jones, who specializes in China's space program and has previously shared crucial information about other ongoing missions.

Neither the caption nor the related section of the report made any mention of the photo being the first of its kind or explained why it was previously classified, raising questions about whether the authors realized its significance.

There is one small caveat. The report notes that China has two active space plane designs — Shenlong and Tengyun, meaning "cloud rider" — and the image's caption does not specify which design we are looking at, according to The Aviationist.

However, there have been no confirmed launches of Tengyun to date. Existing photos of a potential prototype also hint that this vehicle's design looks markedly different from what we can see in the new photo. Therefore, most experts agree that the spacecraft in the image is most likely Shenlong.

What does the new photo tell us?

Until now, all we really knew about Shenlong is that it operates similarly to NASA's iconic space shuttles: It gets launched into space by a rocket and circles Earth before eventually gliding down to the planet's surface, where it can then be refueled and relaunched into LEO.

It is not the world's only active space plane. The U.S. Space Force has its own, the X-37B, which has already completed seven orbital missions since its first launch in 2010 and is currently in LEO experimenting with quantum navigation. Based on the new photos, Shenlong shares many similarities with its American counterpart.

"The Chinese spaceplane has delta wings, payload bay doors, a dark heat shield, and a rear-mounted service module with power-generating solar arrays," technology news site ArsTechnica reported. "In other words, the design of the winged ship is, to a great degree, a copy of the X-37B spaceplane flown by the U.S. Space Force."

However, the two spacecraft are not exactly the same: "The overall arrangement resembles the American vehicle, although differences in wing geometry show that the two spacecraft are not externally identical," according to specialist news site Global Defense News.

It is still unclear how large Shenlong is. The X-37B is 29 feet (8.8 meters) long and has a wingspan of 15 feet (4.5 m), according to Popular Science.

The new image also indicates that Shenlong is most likely not a military asset, Global Defense News reported, noting that "the image does not establish a weapons role."

However, China likely has other space-based weapons, similar to the mysterious "in-orbit" American weapons recently confirmed by U.S. Air Force Secretary Troy E. Meink.

"China has developed and will continue to advance weapons for use against satellites in orbit to disrupt, damage, and destroy other nations' space capabilities," DIA representatives wrote in a separate section of the new report. "Beijing aims to become the preeminent leader in space," they added.

The Shenlong story so far

Since first launching into space on an initial two-day mission in September 2020, Shenlong has completed two feature-length missions: an eight-month stint in LEO between August 2022 and May 2023, and a nine-month spaceflight between December 2023 and September 2024. (The new image was taken during the latter mission).

The space plane is currently on its fourth mission, which launched Feb. 7 on board a Long March 2F rocket from China's Jiuquan Satellite Launch Center, Live Science's sister site Space.com previously reported. In total, Shenlong has racked up more than 800 days in orbit. However, it is unclear whether the same space plane was used on all four missions or if China has more than one space plane in use.

So far, Shelong has released at least nine unidentified payloads around Earth. These objects are most likely small satellites, known as cubesats, but their purpose remains unclear.

The most recent object was deployed in June this year, although astronomer Jonathan McDowell, who specializes in tracking spacecraft in LEO, has since suggested that the spacecraft retrieved the object, potentially with a robotic arm, and rereleased it in late August.

The new report also mentions that the space plane "appeared to maneuver with a companion satellite" during its second mission in November 2022, coming within 330 feet (100 m) of the smaller spacecraft and potentially even capturing and re-releasing it.

This may support an existing theory that the main goal of Shenlong is to "conduct rendezvous and proximity operations" with other spacecraft, and that its payloads may be targets for it to practice flyby maneuvers in orbit.

Editor's note: This article was updated on Oct. 29 to correct a typo. A previous version of the article abbreviated the People's Republic of China as "PCR" rather than "PRC". This has been corrected.

People with inflammatory bowel disease (IBD) experience gut pain that can be severe, and it doesn't always go away when their inflammation is under control and their colonoscopy looks normal. Now, in a new laboratory study, researchers found a previously unknown pain pathway that may explain this phenomenon.

The findings, published Oct. 23 in the journal Science Immunology, also point to a potential way to block that pain.

"Inflammation in the gut has always been thought of like a fire: the sensory nerves alarm because of the smoke and the heat, and when the fire is put out the alarm should stop," said study co-author Dr. Heng Xu, a physician at Ninth People's Hospital in Shanghai. Xu and his colleagues set out to try to isolate what could be causing the pain even when there's no visible "fire" or "smoke."

"What we found is that the tissue itself changes consistency," Xu told Live Science in an email. "It becomes stiff and less elastic, a bit like a scar, and that stiffness alone keeps triggering the alarm even after the fire is out."

In ulcerative colitis, the most common form of IBD, inflammation causes ulcers in the gut, as well as symptoms like bloody diarrhea and abdominal cramping. Several medications can help quell this inflammation, but that doesn't necessarily eliminate patients' pain. The researchers wondered if immune cells that live in the gut might contribute to that ongoing pain.

They zoomed in on a protein called Piezo1; in immune cells, it's known to play a role in inflammation, and in neurons, it contributes to pain signals. The team looked at whether this protein's activity changed in the context of colitis.

"We started with sequencing data that reads cells one at a time, from the gut tissue of patients with ulcerative colitis and from mice with the disease," Xu said. "One cell type stood out: an immune cell that lives permanently in the gut wall, rather than arriving from the bloodstream when there's trouble." The quantity of these cells was higher in colitis than in healthy guts, and the cells carried more Piezo1 than the other cells analyzed.

"They sit touching the nerve endings," Xu added.

In several experiments with lab mice with colitis, the team used a probe to press on the gut tissue and measure how hard it was. This showed that, compared with healthy mice, the gut was stiffer in two models of disease: one with visible inflammation and another with almost none.

They also measured pain levels in both sets of mice. "In mice with almost no visible gut inflammation, the pain was still there, which is why a colonoscopy can look normal while the patient hurts," Xu said.

They then looked at Piezo1 in both sets of mice. The protein sits in the immune-cell membrane, and when the stiffened tissue around it is pulled or squeezed, it's as if a button were pressed and a channel opens, Xu said. This sets off a chain reaction that leads to pain, Xu said.

That's because calcium ions rush into the cell via the channel, and that surge sends a protein called NF-kB from the cell's interior fluid into its nucleus — the control center where DNA is stored. There, NF-kB plugs into a gene, ordering the cell to manufacture nerve growth factor (NGF) that then exits the immune cell.

This NGF, which is known to amplify pain signals in the body, interacts with nearby pain-sensing neurons. These nerve endings grow denser and become hypersensitive, which makes ordinary gut activity painful, the study suggests.

The researchers used chemicals as on-off switches for Piezo1 in immune cells, opening the channel with one and closing it with another. As they did this, they tracked calcium signals and NGF production, and both rose and fell in step with the switch. This result suggests that Piezo1 activity is both necessary for this response and, on its own, enough to trigger it in these cells, Xu said.

Blocking this chain of events abolished the pain hypersensitivity in both sets of mice. The researchers tried completely removing the Piezo1 gene from the gut immune cells and found that this eliminated the pain. Removing the gene also caused no problems in healthy mice, they noted.

The study was "well controlled," said Hongzhen Hu, the scientific director for the Mark Lebwohl Center for Neuroinflammation and Sensation at the Icahn School of Medicine at Mount Sinai, who was not involved in the research. Future research should address the chemical messengers that coordinate inflammation, called cytokines, and determine whether the same chain reaction occurs in human cells, he said in an email.

The mouse experiments also may not reflect long-term, chronic disease in patients, given the mice experienced symptoms only transiently, Xu said.

Xu and his colleagues are now aiming to develop a drug that can target Piezo1 to switch off gut pain locally without suppressing the entire immune system. This would be a more targeted treatment than current options, such as immunosuppressants or opioids.

Other scientists have explored using anti-NGF treatments for other chronic pain conditions but not for ulcerative colitis, Xu noted. Fully blocking NGF might have downsides, he said, since NGF also helps to maintain nerves.

So more work is needed to translate these findings into a treatment. But for now, the work sheds new light on how immune cells can detect a physical change — such as tissue becoming stiff — and convert it to a pain signal.

"For the pain field, that's a conceptual shift," Xu said.

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

The enigmatic and now-extinct Denisovans of China shared traits with Neanderthals, modern humans and Homo erectus, according to a new study that looked at ancient proteins and fossils. But the Denisovans also had several unique skull traits and genetic variants that made them a distinctive ancient human group, according to the researchers ‪—‬ and these traits have now revealed a new face for a Denisovan man.

In the study, published Oct. 21 in the journal Nature, researchers analyzed Denisovan skulls from the archaeological site of Xujiayao in northern China. The Denisovans were a group of ancient humans who lived in Asia and disappeared around 30,000 years ago. This human relative was first identified in 2010 from the DNA of a finger bone discovered in a cave in Siberia.

The Xujiayao bones and teeth were excavated in the late 1970s, long before scientists knew about the existence of Denisovans, and were initially thought to be either Neanderthals or archaic Homo sapiens due to the shape of the fossils and their age: 138,000 to 199,000 years old.

But recent advances in paleoproteomics ‪—‬ the study of bone and tooth proteins that persist longer than DNA ‪—‬ have helped researchers identify Denisovan individuals due to specific genetic variants that differentiate them from other ancient human groups.

In the new study, researchers used paleoproteomic analysis on 20 remains from Xujaiyao and determined that all of them were from Denisovans. This determination then allowed the researchers to study the skull bones closely and figure out what Denisovans might have looked like.

The Xujiayao skulls had some features similar to H. erectus, the researchers wrote, including a low and wide braincase and thick cranial bones. But they also had anatomical features more similar to those of Neanderthals and modern humans, particularly in their bicuspids (the teeth between the canines and molars). The researchers also identified some unique Denisovan cranial traits. The back of the skull, for example, was more vertical and less rounded than in Neanderthals or modern humans.

Armed with a better understanding of Denisovan skull shape from the Xujiayao fossils, the researchers compared them with East Asian Denisovan remains that some experts have assigned to other species, such as Homo juluensis and Homo longi. But the researchers identified similarities that may preclude splitting Denisovans into different species.

"This unique combination of morphological traits, distinct from H. erectus, modern humans and Neanderthal-lineage hominins, supports the assignment of most members of East Asian late Middle Pleistocene archaic Homo as Denisovans," they wrote in the study. This means that Denisovans may have been one human lineage that adapted to diverse ecological zones across Asia over hundreds of thousands of years.

"It is still possible that there are some other lineages that existed in East Asia during the time Denisovans are known to have existed," study co-author Qiaomei Fu, director of the Ancient DNA Laboratory at the Institute of Vertebrate Paleontology and Paleoanthropology, part of the Chinese Academy of Sciences, told Live Science in an email.

"We know from DNA that Denisovans were a very varied group genetically, which split early into different populations," Chris Stringer, a paleoanthropologist at the Natural History Museum in London who was not involved in the research, told Live Science in an email. "These could have developed a lot of morphological variation, which may well surprise us as the sample of fossils grows."

The researchers also produced a new reconstruction of what a Denisovan man might have looked like. A previous DNA study suggested that Denisovans likely had dark skin, brown hair and brown eyes. The new reconstruction shows the Denisovan looking directly at the viewer, with his low, wide braincase mostly obscured by dark hair flowing back from his massive brow ridge. There are clear similarities between the Denisovan man and Neanderthals as well as modern humans, but the Denisovan has a distinct visage all his own.

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

The patient: A 42-year-old woman in Somaliland, Africa

The symptoms: The woman went to the hospital after having three years of chronic, dull pain in her lower abdomen, as well as a growing sense of heaviness in her abdomen that had worsened in recent months.

When doctors reviewed her medical history, they learned that, three years earlier, she had experienced a number of symptoms that seemed to indicate a pregnancy. She recalled her abdomen growing over time and feeling "fetal movements," her doctors noted in a report of the case. Then, the movements stopped, the abdominal growth halted, and the enlargement gradually subsided. She had not sought medical care during or after this apparent pregnancy.

What happened next: When doctors physically examined the woman's abdomen, they found a hard, irregular mass that extended to her belly button and barely moved when they touched it. Blood tests showed mild anemia, meaning she had fewer healthy red blood cells than normal. Her white blood cell count and kidney and liver tests were normal, and a pregnancy test was negative.

An ultrasound revealed a calcified mass and an empty uterus. Calcification is a buildup of calcium that hardens tissue into a solid mass.

To get a better look at the mass, which occupied the woman's lower abdomen and pelvis, the doctors ordered an advanced CT scan to create a 3D model. The imaging revealed that the mass contained clearly identifiable fetal skeletal structures, including a skull, a spinal column, ribs, and arm and leg bones. The mass measured roughly 7 by 5 inches (18 by 13 centimeters).

The diagnosis: Doctors concluded that the woman had a lithopedion, or "stone baby." The term comes from the Greek words "lithos," meaning stone, and "paidion," meaning child.

In a typical pregnancy, an egg is fertilized in a fallopian tube — the structure between the ovaries and the womb — and then travels into the uterus, where it implants in the uterine lining. By contrast, lithopedions most often start as abdominal pregnancies,‬ a type of ectopic pregnancy in which the embryo instead implants on the lining of the abdominal cavity.

There, the embryo shares the space with organs like the stomach, kidneys and appendix. These misplaced pregnancies are almost never viable and are highly life-threatening for the mother. Because the placenta attaches directly to delicate abdominal organs and blood vessels, these carry a severe risk of catastrophic internal bleeding.

If the fetus dies at a developmental stage when it is too large for the mother's body to naturally break down and absorb, her immune system can sometimes treat the retained tissue as a foreign object. To protect the mother from inflammatory complications and infection, the body progressively deposits calcium over the fetal remains, creating a protective casing. In this case, the calcified fetus likely accounted for the woman's chronic abdominal pain and increasing sense of heaviness, her doctors concluded.

The treatment: The doctors performed abdominal surgery to completely remove the calcified fetal mass from the woman's pelvis.

The day after surgery, she developed a mild fever and nausea, but both resolved with treatment. She remained stable and improved during her hospital stay before being discharged in good condition.

Follow-up visits over the next six months showed she had healed well, with a complete resolution of her abdominal pain.

What makes this case unique: Only about 340 cases of lithopedion have been documented in the medical literature over the past 400 years, with the earliest documented in 1582.

This woman's case stands out because she was 42 years old, while many recent cases have been diagnosed in postmenopausal women. (Women typically experience menopause around 51 to 52 years old.) In these cases, the initial ectopic pregnancy occurred during the woman's childbearing years, but she unknowingly carried the calcified remains for decades before developing symptoms. For example, a 74-year old woman from India carried her "stone baby" for more than three decades. By contrast, the woman's recent case was caught after only three years.

The case also highlights the challenges of maternal healthcare in resource-limited settings such as Somaliland, where a lack of access to routine prenatal care and early pregnancy scans can lead to delayed diagnoses. That said, the successful use of advanced 3D imaging and complete surgical recovery demonstrate that excellent outcomes are possible even in these constrained environments, the doctors noted.

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.

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