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 headless 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 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 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.

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

Universities are at a critical point as students and faculty embrace the use of AI. Already, universities like Harvard are introducing courses that feature an AI avatar as an "instructor."

The promises AI offers higher education are familiar: an increase in efficiency as a consequence of less administration, more teaching coverage, better feedback and smarter assessment. But introducing artificial intelligence (AI) systems in an attempt to fix these problems is not the answer. If anything, AI systems will magnify and speed up the bureaucracy that is driving universities' decline.

In practice, the more likely outcome is darker: AI will not simply sweep away the bureaucratic machinery of universities; it will give that machinery a new regime of AI compliance — more policies, more forms, more trackers, more oversight roles and more work downloaded onto faculty who are already stretched thin.

The danger is not that AI will destroy universities but that universities will use AI to preserve the very processes that make them dysfunctional. If this happens, we might see faculty spending less time on research, less time on teaching, and more time on activities that do not directly contribute to the production of knowledge and education of students.

This is already evident in the existing assessment system in the U.K., but shades are creeping into systems elsewhere, providing a window into the future for U.S institutions. A single piece of student work may pass through a plagiarism-detection platform, a grading interface, a moderation spreadsheet for faculty to share feedback, a grade-transfer system, and an exam-board record. Each stage generates its own logins, deadlines, exception rules and audit trails. None of this is inherently malicious. Anonymous marking, moderation, appeals, accessibility and academic integrity are legitimate concerns. But when each concern is implemented as a separate system, the combined effect is administrative incoherence.

In essence, faculty become the human interface between incompatible platforms, spending their time reconciling grades and chasing missing evidence rather than teaching. While this example pertains to U.K. universities, the trend to expand the administrative staff extends to North America. AI simply introduces a new opportunity to increase administration.

AI could, in principle, solve this. It could integrate systems, automate routine reporting, draft feedback, identify inconsistencies and remove duplicate data entry. Yet the institutional incentive is rarely to remove work; it is to make work visible. A university that automates a broken workflow does not necessarily simplify it. It may simply produce faster reports about the broken workflow, more sophisticated dashboards and more elaborate evidence of compliance. The bureaucratic impulse survives by changing its vocabulary: risk management, assurance, transparency, governance, responsible innovation.

At least one possible outcome is that universities will create AI-use policies, require module-level AI statements, mandate disclosure forms, introduce approved-tool lists and establish review committees. Faculty will be asked to redesign assessments, monitor suspected misuse, document their decisions, complete training, and explain their approach to students. Much of this labor will be invisible. It will appear not as a new job title but as an additional expectation attached to teaching.

This creates a familiar pattern: responsibility without authority. Faculty are expected to make consequential judgments about academic integrity, fairness, privacy and assessment validity. But they do not control procurement, system design, institutional policy or disciplinary procedures. When something goes wrong, the academic is exposed; when the system works, the institution claims the credit.

That asymmetry is corrosive. It teaches committed staff that careful judgment is not valued as expertise but rather as a compliance risk to be managed, and the consequences will fall unevenly. Experienced faculty, after voicing their concern to no avail, may leave, retire early or disengage. Early-career academics, already precarious because they don't have tenure, will have the least power to resist. Students will receive less of the resource that matters most: sustained intellectual attention.

One possible outcome is that universities will encourage the development of faculty AI avatars and cut hours and employment. The institution will then justify hiring more ‪—‬ not fewer ‪—‬ compliance and "educational enhancement" staff to manage and maintain these AI avatars, negating the idea of efficiency and cost savings. In this scenario, bureaucracy will expand to manage the problems created by its own expansion while undercutting quality for the students who are paying high tuition fees. One might need to hire staff for oversight of these avatars, administrators and lawyers to manage licensing agreements, quality control staff in case things go wrong, and IT teams for integrating them into learning platforms and websites.

There is an alternative to the administrative tasks. AI should be governed by a simple institutional rule: no new compliance requirement without the removal of an equivalent existing burden. If a university requires assessment redesign to accommodate AI, or the introduction of new technology, it should provide protected time, technical support and a single integrated platform. If it expects faculty to manage AI use, it must give them clear institutional backing rather than leaving them to improvise. And critically, it should show how the technology makes work more efficient before rolling it out across the board.

But the deeper issue is not technology but institutional purpose. A university exists — or should exist — to cultivate understanding, judgment and intellectual independence. If its systems consume faculty time, fragment the student experience, and reward documentation over learning, then AI becomes another instrument of managerial self-preservation. The question is not whether universities can adopt AI. It is whether they can resist using AI to automate their own absurdities.

If they cannot, the outcome will be an educational system that looks progressively sophisticated while becoming increasingly hollow ‪—‬ full of monitoring, low on trust; rich in measuring, poor in teaching; obsessed with compliance, indifferent to the people who make education possible; overly procedural sans intellectual life. It will become an audited theater of learning not worth students' time.

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Artificial intelligence (AI) tools like chatbots are becoming part of everyday life, helping people write messages, answer questions and learn new skills. While some of these processes may save people time, a new study reveals a possible new downside of consistently relying on AI assistance.

The research, presented at the 2026 Conference on Language Modeling in San Francisco earlier this month, found that people who relied on AI assistance for tasks like math problems and reading comprehension were more likely to give up or struggle when the assistance was taken away. The findings suggest that leaning too heavily on AI could weaken people's motivation to push through challenges.

The research raises the question of what happens when people stop exercising their brains. So do you think AI is making you less motivated, or even "dumber," or is it simply making you more efficient? Vote in our poll, and let us know your thoughts in the comments.

A male tiger approaches his cubs and greets them with a head-bobbing motion while their mother rests nearby. The surprising interaction, captured in the PBS Nature documentary "Tiger Island," a two-part series that follows two big-cat families across Nepal.

The footage marks the first time a tiger "family" has been documented spending time together, and it could challenge conventional assumptions about how the seemingly solitary cats behave around their young, said Dan O'Neill, a wildlife biologist and filmmaker who contributed to "Tiger Island." Previously, it was thought that tiger moms raise their cubs for up to two years without any help from the male tiger.

But this may not be the norm.

"It just shows that we really know nothing about them," O'Neill told Live Science. "And they're so much more complex than people realize."

That's just one of the scenes in Tiger Island that challenges our understanding of the tigers' solitary nature. In another scene, a female tiger cares for another tigress's cubs.

"We have these very rigid ideas of how these animals live," O'Neill told Live Science. But the natural world is "diverse and ever-changing," and tigers are no exception, he said.

The footage of the female caring for another tiger's cubs could offer clues about how mother tigers protect their young. Male tigers, like male lions, sometimes kill cubs ‪—‬ a behavior known as infanticide ‪—‬ particularly when a new male takes over a territory. Allowing another female tiger to care for cubs might help more cubs survive to adulthood, O'Neill suggested. Previous observations of female tigers have shown females helping to co-parent each other's cubs, but it's a rare event.

To capture these scenes, the crew used drones with powerful optical-zoom lenses and quiet propellers to observe the tigers in places that were difficult to access without disturbing the big cats. Traditional camera traps often capture animals along trails, leaving much of their private lives unseen. O'Neill noted that the drone propellers were quieter than the local bees where the filming took place, thus giving the crew candid views of the tigers as they went about their lives.

Solitary animals in urban jungles

Though tigers (Panthera tigris) are solitary animals, they often live close to or share habitat with human communities. That means tigers sometimes attack people and kill livestock, O'Neill said. "It would be absolutely naive and wrong to suggest that they [attacks on people] don't happen," O'Neill said. As a result, conservation efforts must account for the circumstances in which people and big cats encounter one another, rather than treating human communities as separate from wildlife, he said.

The same issue affects other big cats. O'Neill, a researcher with the wild-cat conservation organization Panthera, has spent years studying jaguars, pumas and snow leopards. He said the popular image of these animals living in remote wilderness can obscure how closely they overlap with human lives.

For O'Neill, conservation requires more than studying the animals' behaviors or protecting their habitats. It also means helping people who bear the cost of living alongside these apex predators.

"Helping those people is how you help tiger conservation," he said.

In the U.S. "Tiger Island" Part Two airs on Wednesday, Oct. 28 at 12:30 am on the PBS channel.

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Scientists have sequenced the genomes of three Late Stone Age people who lived in Europe 30,000 years ago and discovered that they had closer biological ties than researchers previously thought. The new finding suggests that places like southwestern France may have been critical cultural hubs during the last ice age.

Shortly after Neanderthals disappeared from Europe, a Stone Age culture known as the Gravettian spread across the continent. Artifacts found during archaeological excavations ‪—‬ including portable art, such as "Venus figurines" ‪—‬ have shown that the Gravettian culture lasted from about 34,000 to 25,000 years ago. But ancient DNA has been recovered from only two dozen human skeletons from the Gravettian period, so questions about these people's ancestry remain unanswered.

Based on the small number of genomes from Gravettian people that were previously sequenced, experts believed that groups in Western Europe were largely separate from groups in Eastern Europe. But in a study published Oct. 23 in the journal Science Advances, researchers sequenced the genomes of three people who lived in what are now Spain, France and Italy during the Gravettian period. They discovered that one person had mixed genetic ancestry that revealed East-West exchange at least 30,000 years ago.

"Our results show that eastern and western European populations were not as genetically isolated as previously assumed," study first author Pere Gelabert, an evolutionary anthropologist at the University of Vienna, said in a statement.

The new information about mixed ancestry comes from a woman who died around 30,000 years ago and whose bones were found in Isturitz Cave in southwestern France. Originally used by Neanderthals, Isturitz Cave was occupied off and on from about 80,000 to 10,000 years ago. Cups made out of human skulls dated to roughly 15,000 to 12,000 years ago have also been found in Isturitz Cave.

Researchers found that the DNA from the Gravettian woman in Isturitz Cave was most similar to the previously known Western European genomes, but with an intriguing connection to Eastern and Central European groups.

This discovery of gene flow from the East is uncommon for the Late Stone Age, also known as the Upper Paleolithic, the researchers wrote in the study. It "could be explained by movements of people from Eastern Europe during the Gravettian period, which eventually contributed to this ancestry in Isturitz." Specifically, the researchers dated this "pulse" of gene flow to about 31,500 to 32,500 years ago.

The DNA evidence supports the archaeological theory that Isturitz Cave was an important cultural and biological hub for tens of thousands of years during the Late Stone Age, as the cave was located at a critical passage between continental Europe and the Iberian Peninsula, the researchers wrote.

All three newly sequenced Gravettian genomes revealed close biological connections to Western European groups, as well as genetic traits suggesting they had dark skin, dark hair and dark eyes. What's more, all of them had parents who weren't closely related to each other, suggesting that those populations may have actively avoided inbreeding.

"Overall, our results suggest that population structure and gene flow in western Europe during the Gravettian were more complex and dynamic than previously assumed," the researchers wrote.

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A proposed change to decades-old guidance on hepatitis B vaccination would lead to a dramatic increase in chronic hepatitis B virus (HBV) infections among young people, a new modeling study predicts.

Previously, the Centers for Disease Control and Prevention (CDC) recommended that all newborns be vaccinated against HBV within hours of birth ‪—‬ a strategy known as "universal birth-dose vaccination." But in December 2025, the Advisory Committee on Immunization Practices (ACIP) advised ending this recommendation, and the CDC accepted that advice.

The new guidance would recommend birth doses only to babies whose mothers tested positive for HBV or whose HBV status was unknown. The guidance suggests that mothers who test negative should instead ask their doctors about whether their child needs a birth dose — an approach the CDC calls "shared clinical decision-making." The new recommendation states that babies who forgo the birth dose should be at least 2 months old before starting the HBV vaccine series.

Health experts widely criticized the proposed change when it was announced, and for the moment, its implementation has been put on pause by legal action. The modeling study, published Oct. 19 in the journal Annals of Internal Medicine, predicts what would happen if it came to pass.

"Overall, this modeling study has many strengths and I think presents an accurate projection of how the vaccine recommendations may impact future chronic HBV in the U.S.," Dr. Norah Terrault, a transplant hepatologist at the University of Southern California Keck School of Medicine who wasn't involved in the study, told Live Science in an email.

When caught in infancy or early childhood, over 90% of HBV infections become chronic. About 15% to 25% of people with chronic HBV go on to develop liver scarring (cirrhosis), a form of liver cancer called hepatocellular carcinoma, or another chronic liver disease. So, an uptick in chronic HBV infections would translate to an uptick in these harmful liver conditions.

Increases in infection

"Not every pregnant person is tested for hepatitis B," said study co-author Dr. Amir Mohareb, an infectious-diseases physician-investigator at Massachusetts General Hospital and Harvard Medical School. For those who are tested, there's a chance their results are inaccurate or that they're not provided the right care after testing positive. "Something can be missed at any step in the care process, so the vaccine dose at birth provides protection," he said.

Mohareb and his colleagues built a simulation model using published data, including the current prevalence of HBV and the screening rate among pregnant people. The team also factored in the HBV test's sensitivity, the share of children who are fully vaccinated by age 2, and the risk of developing chronic HBV infection in different age groups. They made estimates of how often children are exposed to the virus through contact with infected household or community members.

HBV is "very, very transmissible," Mohareb said. It can spread from mother to child at birth or through exposure to tiny amounts of bodily fluids, like blood from a scratch, after birth. So, even if a baby does not get HBV from their mother, if they are unvaccinated, they can still get from another family member or from other children.

With this data, the researchers tested what would happen if vaccination were postponed to 2 months of age for babies whose mothers tested negative. Among babies born in 2026, 19% more would have chronic HBV infections by age 20, compared with universal birth-dose vaccination, they found.

In this scenario, the babies would still start the HBV vaccine series, albeit two months later than usual. However, the CDC's proposed recommendation offers more wiggle room; it says that parents should consult with their children's doctors to "decide when or if their child will begin the hepatitis B vaccine series" at all.

The researchers ran a stimulation to compare these two scenarios: one where kids get their first shot two months late and one intended to capture this looser "shared clinical decision-making" scenario.

"Other vaccines whose recommendations employ similar language had uptake as low as 25%," Mohareb noted. This aspect of their modeling has some uncertainty, he emphasized, since it's unknown exactly how the public will respond to such loosening of the guidance.

The researchers assumed that about 87% of kids would complete the vaccine series by age 2 under the deferred strategy, while only 50% would under the shared decision-making strategy. That 50% coverage, in turn, would increase chronic HBV infections acquired by age 20 by 83%, and about 50% and 70% of those born under that guidance would be susceptible to HBV infection at age 20.

That's about 1.8 million people in this age group per year, compared with fewer than 250,000 under universal birth-dose vaccination. "This represents a population that is at risk for acquiring HBV via sex, drug use etc — behaviors more prevalent among young adults," Terrault said.

A "missed opportunity to protect against infection"

To test the robustness of the findings, Mohareb's team varied the most uncertain inputs across wide ranges and ran the model 1,000 times. In every simulation, the birth-dose strategy led to fewer chronic infections than either alternative.

These conclusions seem "robust" because "they are the same conclusions no matter how we change the numbers of the model," Mohereb noted. Though of course "the specific magnitude of change depends on how many people defer vaccination," he said.

The new study does not specifically show how many additional cases of liver disease or cancer would result from the uptick in HBV infections. But Terrault said that the risks of liver failure, cirrhosis and liver cancer "would be anticipated to increase due to the missed opportunity to protect against infection."

Mohareb stressed that he is in no way opposed to the principle of shared decision-making between doctors and patients. "They should always make the decision together," he said. "But we rely on our public health agencies not to tell us that we should be making decisions with the patient, but rather to tell us what policy would make us healthier as a country."

Childhood HBV infections in the U.S. dropped from more than 25,000 cases a year in 1985 to fewer than 100 reported cases in 2024. This steep decline is credited to HBV screening during pregnancy, antibody treatment for babies born to HBV-positive mothers and universal birth-dose vaccination.

"Certainly without following a universal dose vaccination recommendation there would be a lot more hep B infections early in life," Dr. Brian McMahon, a hepatologist and the director of the Liver Disease and Hepatitis Program at the Alaska Native Medical Center, told Live Science in an email.

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

Native Hawaiians and Easter Islanders genetically descend from the same "ultravoyager" Polynesian group that crossed vast distances of ocean to reach these remote islands, a new study finds.

Easter Island (also known as Rapa Nui) and Hawaii are part of Polynesia, a group of more than 1,000 islands spread over an area of the Pacific Ocean roughly equal to the areas of North and South America combined. Hawaii and Easter Island are the farthest of these isles from each other, at about 4,500 miles (7,200 kilometers) apart — around the distance from San Francisco to Lima, Peru.

The researchers discovered the connection by analyzing the genomes of 1,050 modern individuals across Polynesia, including 317 Native Hawaiians and 12 Easter Islanders. "Each person's genome contains genetic code from both parents, and from all four grandparents, and their parents, and so on," study co-author Alexander Ioannidis, a computational geneticist at Stanford University, told Live Science. "Each genome encodes an enormous number of ancestors. So with even a few individuals, we can get information about an enormous number of people from each island."

Specifically, the scientists compared the length of chromosomal segments shared among people from different islands. The longer these shared segments are between two people, the more recently they shared a common ancestor.

Even though Hawaii and Easter Island are far-flung, the researchers discovered that the Indigenous people of Hawaii and Rapa Nui are the most genetically related to one another. The team reported its findings Oct. 8 in the journal Science.

"This was really shocking at first — these islands are so distant from one another," Ioannidis said.

The scientists found that Hawaii and Easter Island were likely both settled by members of a single "ultravoyager" culture from the Mangareva islands, about 3,440 miles (5,530 km) southeast of Hawaii and 1,600 miles (2,600 km) west of Easter Island. (In 2020, the researchers found that members of this ultravoyaging group had mixed with Indigenous people in what is now Colombia, although it's unclear if this partnering occurred on an island or on the continent.)

"Once you know there was this extremely capable long-distance ultravoyaging culture capable of reaching one of these islands, having it reach the other makes more sense," Ioannidis said.

The area near Mangareva, including the Austral Islands, the Society Islands, the Marquesas Islands, and the Tuamotu Archipelago, "spans an area the size of Europe," Ioannidis said. "Sailing in-between these islands would have required skilled navigation. So it makes sense that developing such long-distance navigation skills would have ultimately helped people settle far-off Easter Island and Hawaii."

All in all, these genetic findings suggest the ancestors of Native Hawaiians and Easter Islanders shared some time together as a common group after splitting away from the population of ancient Mangareva. Some members of this group then went on to settle Hawaii, and others from this Mangareva group voyaged to Easter Island.

This new genetic data linking Hawaii, Easter Island and Mangareva "agrees very well with what we see archaeologically," Patrick Kirch, an archaeologist at the University of Hawai'i at Manoa who did not take part in this research, told Live Science. "It gives scientists a lot of confidence when independent lines of evidence from different disciplines give similar results."

Founder effect

The researchers also investigated the effects of genetic bottlenecks that resulted when these islands were settled by small numbers of people — phenomena known as "founder effects."

"If you have a rare genetic trait that happens to occur in this small number of individuals, if this small population grows rapidly, this trait can go on to show up in a high percentage of the resulting population," Ioannidis said. "So if a rare genetic variant once only affected a few people, it can start affecting a decent number of individuals."

The scientists found that Native Polynesian populations examined in the study often experienced a compounding set of founder effects over time. This is because islands settled by a few people then went on to send out small groups to settle other islands, and so on.

Previous research has looked at the founder effects in groups of European descent, such as the Amish, Finns and Ashkenazi Jews, resulting in standard screenings for certain genetic conditions in these groups.

The new study revealed that an even stronger founder effect has been overlooked among Native Hawaiians, with founder effects more than 10 times larger than in those European groups.

"The founder effect doesn't just reflect genetic diversity, but also cultural and linguistic diversity," Kirch said. "It probably helps explain why the cultures of eastern Polynesia all share a lot in common — they all trace to one central group."

These findings not only shed light on Polynesians' past, but also their current health. The researchers found that three genetic variants that are exceedingly rare among the global population — linked with dislocated lenses in the eyes, progressive vision loss, and kidney failure — are carried by 2 to 3% of the eastern Polynesians they studied.

"There should be a lot more resources going into learning more about gene variants of potential clinical significance among this population of Native Hawaiians, which is twice as large as the U.S. Amish population," Ioannidis said. "There are really opportunities for precision health here."

Astronomers using the James Webb Space Telescope (JWST) have discovered a galaxy with a glowing ring of newborn stars shining in the early universe. The galaxy, which the researchers observed as it appeared just 2.1 billion years after the Big Bang, is the most distant ring galaxy ever found.

The ring galaxy, known as GS18660, may be the result of a collision between two galaxies, the researchers reported in their study, published Sept. 8 in the journal Astronomy & Astrophysics.

It's rare to find the possible snapshot of a merger like this, given the timescales involved in these systems, Christopher Conselice, a professor of extragalactic astronomy at the University of Manchester in the U.K. who was not involved in the study, told Live Science. Although interactions between galaxies may have been common in the early universe, the creation of ringed systems like this is thought to be unusual.

"In this sense, the galaxy system is quite unique and may give us important information about early galaxy formation," Conselice said in an email.

A surprising discovery

Scientists selected GS18660 for observation because it looked stretched out in older Hubble Space Telescope images.

"We therefore did not target GS18660 specifically as a ring galaxy," Michele Perna, a postdoctoral researcher at the Spanish Astrobiology Center and the first author of the study, told Live Science in an email. "When we observed it with JWST [Near-Infrared Spectrograph instrument], the much more detailed data revealed the prominent ring structure and allowed us to investigate the galaxy in three dimensions."

Using JWST, the team looked at the galaxy's unique shape, tracked the motions of its hot gas, analyzed the gas's chemical properties, and studied the galaxy's star formation history.

Intruder-driven rings

When a small galaxy plunges through the center of a larger galaxy, the impact creates a wave of dense gas that ripples outward, similar to how water moves when a stone is dropped into a pond. As a result, a collisional galaxy is formed. Gas piles up along the wave and forms stars, producing a ring. These galaxies are rare in the local universe, and the few candidates found in the distant universe have been hard to confirm.

Several clues support the case for GS18660 as a collisional ring galaxy. For one, the researchers spotted a small companion galaxy, moving away from GS18660 at about 264 miles per second (425 kilometers per second). They also detected a bridge of gas linking the two, and the velocity along it changed, Perna noted. The change in velocity along this bridge-like structure indicates that the companion and GS18660 may be interacting.

Its position is also important, Perna added ‪—‬ the companion is located roughly along the main galaxy's minor axis, consistent with where an intruder would be expected to appear after a head-on plunge through the galaxy's disk.

Backed by stars

Using the companion's speed and distance, the team estimated a rough timeline for the impact. It revealed that the collision happened about 17 million to 42 million years earlier in the galaxy's history. This time scale seems reasonable, Conselice said.

He explained that it is difficult to determine the age of a past interaction directly, but that if one did occur, it must have happened around the time a rapid star-formation episode began and its age should be consistent with the average ages of the star clusters.

Looking at star formation rates with different instruments, the team estimates that 10% to 20% of the stellar mass in the ring formed in the past few tens of millions of years. This suggests that the collision and the ring's burst of new stars might have happened at the same time, so they were most likely caused by the same event, Perna explained.

"It is not, by itself, definitive proof of a collision, but together with the bridge and the ring morphology, it strengthens the case for a recent impact," Perna noted.

The discovery may also shed light on how common these kinds of collisions used to be. Whereas earlier estimates suggested that collisional rings in the early universe might be about as rare as they are today ‪—‬ around 1 in 10,000 galaxies ‪—‬ the new findings hint that head-on collisions that form ring galaxies may be more common in the early universe.

"If GS18660 is confirmed as a collisional ring, it would therefore suggest that we need to revisit our estimates of how frequently these systems occur in the distant universe," Perna said

Another explanation?

The team expressed caution about how much the data can prove. "It is really the combination of several pieces of evidence rather than one single observation," Perna said. "So we regard the collisional interpretation as our preferred scenario rather than a definitive conclusion."

Conselice thinks the evidence presented in the paper is consistent with a genuine collisional origin for the ring. "It looks to me like the merger hypothesis is more likely, given the nearby galaxy intruder and the stability of the intruder galaxy and the main galaxy itself," Conselice said. “Overall, it is convincing evidence that a past interaction and/or merger has occurred for this galaxy system based on the light distribution."

The other competing explanation involves a stellar bar. It proposes that the ring was not made by an intruder at all. GS18660 also shows a bar-like structure running north to south, and bars can funnel gas and stars into rings at specific distances from the center. Perna said the team cannot yet tell whether this is a true stellar bar or a result of the interaction.

A bar would be an exciting finding, too. JWST has already discovered barred galaxies in the early universe, including CEERS-2112. But researchers have not yet found a clear example of a bar-driven ring so early in the universe.

"Whether the ring was triggered by another galaxy or by the internal dynamics of GS18660," Perna said, "the result would tell us something important about how galaxies were already becoming structurally organised when the universe was only a few billion years old."

Editor's note: This article was updated on Oct. 29 to correct a typo. In the image caption, the lead researcher's surname was mistakenly written as "Pera," rather than "Perna." This has been corrected.

An experimental medical implant that removes excess sugar from the blood has shown promise in treating diabetes and obesity in tests with lab mice.

Coupled with a continuous glucose monitor, which tracks blood sugar levels in real time, the tiny device is designed to adjust blood sugar levels according to a patient's needs. It does so using a chemical reaction powered by electricity. In the mouse experiments, it prevented sudden insulin spikes and promoted fat loss.

The implant, described Oct. 22 in the journal Science, could offer a completely new way to treat diabetes and obesity, study co-author Martin Fussenegger, a professor of biotechnology and bioengineering at ETH Zurich, told Live Science in an email. His team is now working toward testing the device in additional lab animals, and eventually, humans.

About 790 million people have type 2 diabetes globally, and over 1 billion have obesity. People with obesity often have insulin resistance, in which cells don't respond to insulin well and can't take in the sugar they need from the blood. At first, the body makes more insulin to compensate, but eventually, it can't keep up; this sets the stage for prediabetes and type 2 diabetes. About 90% of people with type 2 diabetes also have obesity or are overweight.

At the same time, chemical reactions in the liver convert the extra glucose in the blood into fat stores, contributing to further weight gain.

Current treatments for these conditions focus on either lifestyle changes, such as diet and exercise, or long-term medications such as metformin, which lowers blood sugar, and GLP-1s, which reduce appetite to promote weight loss. But Fussenegger and colleagues wondered if they could target the glucose directly.

They designed an inch-long reactor that converts glucose into a harmless byproduct, called gluconate, through a controlled chemical reaction triggered by tiny amounts of electricity. This transformation takes place at an electrode coated with gold and platinum nanoparticles embedded within a graphite felt.

Crucially, the reaction occurs only when the device receives sufficient electricity, so the glucose removal can be switched on and off by controlling how much power is supplied to the implant.

The device is wireless and is both powered and controlled from an ordinary smartphone. The phone emits low-level radio frequency energy, which the implant's electronics then convert to a stable DC current to activate the reaction. Combined with a glucose monitor, the device detects high blood sugar and then sends feedback to the smartphone, which then adjusts the amount of power transferred to the implant.

"In principle, this enables the device to remove more glucose when [blood sugar] levels are elevated and reduce its activity when glucose returns towards the desired range," Fussenegger said. "The objective is to create an autonomous system that continuously adapts to the patient's metabolic needs."

The team tested this self-regulating medical device in mice with both diabetes and obesity. Over six weeks, the mice fitted with the implant had much more stable blood sugar levels than the untreated mice did. They also lost an average of 10% of their body weight.

Because the mice's glucose was consistently maintained within normal levels, the body's metabolic chemistry shifted toward fat burning, while the on-off regulation of the glucose-removal reaction prevented the mice's sugar levels from falling below safe limits.

It's an exciting proof of concept, Fussenegger thinks. However, "one important challenge is demonstrating that the device can convert sufficient quantities of glucose in a human while maintaining long-term safety and catalytic efficiency," he said. In other words, they still need to show that the chemical reaction works at the larger scale required to treat a human patient.

In a separate test, the team introduced the device to a large beaker filled with a sugary solution, to see if it could cope with larger volumes of glucose. The amount, about 1.3 gallons (5 liters), was similar to a person's total blood volume. The device still effectively controlled sugar levels in this larger system.

The test is not a substitute for research in larger animals and human patients, though, Fussenegger said. Those studies are the team's next priority.

Importantly, "our device is not intended to replace healthy nutrition, physical activity, or preventative medicine" for the treatment of diabetes and obesity, Fussenegger said.

"Obesity and type 2 diabetes are complex conditions involving much more than elevated glucose levels," he added. "We see it as a potentially powerful addition to the therapeutic toolbox, one that could eventually be combined with established treatments and lifestyle interventions."

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

This eye-catching satellite snap from a decade ago shows a pair of hurricanes barreling toward Hawaii. The clouds swirling around the twin cyclones make them look eerily like the eyes of a pale face smiling up at space. The sight appears even spookier when viewed on a weather map (see below).

The surprisingly symmetrical storms — Hurricane Madeline (left) and Hurricane Lester (right) — were the 14th and 13th named storms, respectively, during 2016's Pacific hurricane season, which is tied for the sixth-most-active year on record, with 22 total named storms.

Madeline peaked as a Category 4 storm on Aug. 30, reaching maximum wind speeds of around 130 mph (210 km/h). Lester also briefly became a Category 4 storm on Sept. 1, reaching a maximum speed just below Madeline's, but it quickly weakened to Category 3.

On Aug. 30, the day after the image was taken, Madeline was just under 400 miles (650 kilometers) from Hawaii's Big Island, while Lester was around 900 miles (1,450 km) behind on the same trajectory, according to NASA's Earth Observatory. At the time, meteorologists were uncertain whether the pair would hit the island.

The Central Pacific Hurricane Center later issued a hurricane warning for the state of Hawaii, saying that Madeline, in particular, would pass "dangerously close to the Big Island," according to the Earth Observatory. However, neither storm ended up making landfall. (In the photo, the Big Island is obscured by reflected sunlight, known as a sunglint, on the left side of the image.)

Madeline eventually passed south of Hawaii on Aug. 31. However, by then, it had been downgraded to Category 1. Lester passed north of the Big Island on Sept. 2 and came within around 130 miles (210 km) of Honolulu, before sharply turning northward, where it petered out.

Although neither hurricane made landfall — meaning the eye of the storm did not pass over a landmass — they still caused high winds, heavy rainfall and strong surf across the state.

Despite being in the middle of the corridor where most Pacific hurricanes form, Hawaii's islands have surprising good luck in avoiding the supercharged storms.

For example, in 2025, Hurricane Kiko was similarly spotted from space bearing down on the island state. But like Madeline and Lester, it suddenly changed course and weakened at the last minute.

Hawaii usually manages to dodge the worst effects of hurricanes for two reasons. First, the islands are surrounded by a near-constant area of high pressure on their eastern side, where most hurricanes come from. Second, strong winds often blow eastward across the islands, according to FOX Weather. These factors create a sort of invisible shield around the islands, causing storms to skirt around them.

However, given the recent rise in extreme weather events across the globe — caused by human-caused climate change — as well as changes to regional weather patterns, the islands may not stay so lucky forever.

For example, in August and September, two hurricanes — Lowell and Lala — skimmed unusually closely past the island of Kauai, causing a significant amount of damage to power lines, boats and other coastal infrastructure. Researchers think the ongoing "super" El Niño, which officially began in May and has already caused record-breaking sea surface temperatures in the Pacific Ocean, may be partially to blame for these storms, according to The Guardian.

See more Earth from space

Over the past six years, orcas have made headlines for a unique behavior: Some individuals have repeatedly damaged or destroyed rudders on boats. The behavior has prompted a wide range of explanations, including that it's playful, a form of revenge, a warning against getting too close to the pod, or even a type of cultural transmission, in which one orca observes another interacting with a boat and then imitates it.

But Christian Frings, a cognitive psychologist who studies how humans control their actions, thinks it could be deliberate.

While Frings, who is also chair of general psychology and methodology at Trier University in Germany, does not study orcas directly, he believes that theories developed to explain human behavior could provide insight into this orca behavior. Orcas (Orcinus orca), he said, may be a "test case" for whether a wide variety of species can anticipate how their actions will change the environment and then take those actions deliberately, with the goal of making those changes.

He published his theory as a commentary Sept. 8 in the journal Animal Cognition.

This doesn't necessarily mean orcas have wicked motives or are ramming boats with the goal of sinking them and scaring or harming people. It may be that orcas just like the sensation of smashing into a rudder or being in the water with a wonky, disabled boat. Once they learn this, they anticipate the effect — for example, how a boat moves or feels when the rudder is damaged — and then carry out the learned action sequence that creates that effect.

Frings' theory doesn't attempt to explain why orcas (also called killer whales) would seek to damage a boat or rudder. "Why they want this effect is a secondary question and while of course interesting it touches a quite different topic," Frings told Live Science via email.

Live Science spoke with Frings about his hypothesis and why theories that describe how humans execute a series of motor behaviors — called action control frameworks — might help us understand how other complex animals behave in the wild.

Kenna Hughes-Castleberry: Why is it important to study orca behavior, and what can studying orcas tell us about animal cognition?

Christian Frings: In truth, I'm the wrong person to get that question because I should mention right from the start that I'm a cognitive psychologist. So usually, I'm studying human behavior. So, it's not really that I'm interested in orcas, per se, more in the question of what is actually comparable between human action control, human cognition and animal cognition.

KHC: Can you explain the action-control framework for our readers?

CF: It's a group of theories. The most important point is that agents — humans and maybe orcas — control their actions by actually anticipating the behavioral and the sensory consequences of their actions.

So let's take the example of turning the light on. The action starts with anticipating how it will look when the light is turned on. It does not start with pressing the light switch. It starts with the visual effect you're going to produce. This visual effect then actually retrieves from memory a motor program, and this motor program actually produces the anticipated effect. So it's all about anticipating action effects.

In the human action-control literature, that is the most dominant view from different theories of how humans actually control their behavior: by anticipating the effects they're going to produce.

KHC: How does that apply to the orca behavior?

CF: The typical explanation for [the boat-attacking behavior] is more stimulus response or cultural transmission. Stimulus response would mean, in this case, the rudder elicits an approach or attack behavior. So any rudder should just elicit this behavior. [Editor's note: Stimulus-response theory is a psychological concept in which a stimulus triggers a particular response from an individual. Examples include a cat being sprayed with water when on the couch and jumping off the couch in response, or a dog salivating when it smells food.]

Cultural transmission would actually be observational learning. That means one orca sees how another orca is attacking a rudder and then just imitates the behavior.

I'm not saying that these explanations [stimulus response or cultural transmission] are wrong, by the way. I just want to add an additional layer of explanation.

I suggest that they actually anticipate the sensory consequences of their action. So maybe they anticipate how it would look and how it would feel if they destroy the rudder. I would not call it [their behavior] play, but maybe they're just testing or probing what kind of effect they're going to produce.

It's a little bit like human babies, when they start to move — or move their arms or move their legs — they're also typically trying to produce effects, right? It's also when they develop language, this kind of babbling, right? That is a kind of testing or probing action effects.

Maybe this is something the orcas also do. I don't know. But at least it's [another theory].

KHC: So would the orca be anticipating something like the boat becoming impossible to steer?

CF: Actually, no. Let's assume for a moment it [that a broken rudder is] what they want to produce — because they somehow anticipate how it would look and how it would feel if this yacht cannot be steered anymore.

If they can anticipate, then this anticipation of this effect will retrieve from their memory what they have to do to actually produce this effect. And it's not about [higher-order] thinking. That is a very important thing.

So we do not need human-like intentions to impose that on the orcas. I'm not saying that, because I really think it's, in a way, comparable with turning a light on. When you turn your light on, you also do not have big thoughts about that. You just want to turn your light on. So you want to produce an effect, and you do not think about all the different, quite complex muscle movements you have to do if you actually press the light switch.

I would say, again, it does not really need higher-order cognition or something like that. We do not have to impose motives or complex thoughts on the orcas for that.

KHC: What are the bigger implications if your theory is correct?

CF: My point is just to look at this behavior from this somewhat different angle, adding this layer about action effects. Because if you, for a moment, take my ideas for granted and say, "OK, maybe he has a point," then this opens up the possibility to manipulate the orca behavior.

Because if the orcas anticipate effects and this action effect produces a certain behavior, if you change the effect — let's say the rudder [material] or the shell of the boat so that the orca thinks he's producing a certain action effect — then he shows his behavior, but this behavior does not produce the action effect anymore. So the orca will probably change the behavior. It might be dangerous because it might elicit somewhat different — maybe even more dangerous — behavior of the orcas, but it might also stop it.

But it gives you a natural angle to manipulate the orca behavior. [Editor's note: In a follow-up email, Frings noted that this could involve testing a different version of the boat rudder. If the original rudder, when damaged, leaves the boat floating in a "helpless" way, a second one could be tested that allows the boat to be maneuverable even when attacked. If Frings' hypothesis is right, then by breaking the link between the orcas' planned actions (ramming the boat) and the outcome they want (helpless boat), you could change the orcas' behavior.]

But again, if you try to change it this way, it might be a little bit dangerous. So I would not suggest doing that with a boat with real people on it, because if you change the environmental consequences, they [the orcas] might actually go a little bit crazy. Maybe they might try to produce this effect with a different kind of behavior, and that could be even more aggressive. But I don't know. I can't predict that.

KHC: So the orcas are a case study to test this framework, right?

CF: Exactly. And for the general approach, it's important to try to find action frameworks that can travel across species that are not specific for one particular species. Because at the moment, we might have action-control models for humans or action-control models for the great apes.

But maybe we can just have a family of action-control frameworks, because maybe orcas and humans, and at least the great apes, control their behavior concerning action effects in quite the same way, to be honest.

Another important point here that makes it, for me personally, very interesting: This is behavior in the wild. So a lot of the research on action control is typically in the lab under very controlled conditions, so in a way, this is moving from humans to orcas but also from lab into wild behavior.

I think one misconception is actually that the models from the lab are not applicable to behavior in the wild. That's not only true for orcas; it's also true for humans. And I don't like that.

And again, this paper is a nice showcase that lab models can actually be used to explain behavior in the real world.

This interview has been condensed and edited lightly for clarity.

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A pioneering NASA space telescope is no more. In sad news for Swifties everywhere, the Neil Gehrels Swift Observatory has officially ended its mission after more than 20 years of tracking the most powerful explosions in the universe since the Big Bang.

According to a NASA announcement, the Swift team shut down the telescope's science operations Tuesday (Oct. 20) after the observatory fell too low in its orbit to continue taking reliable measurements of the cosmos. In the coming weeks, Swift will drop even further, eventually passing a point of no return and taking a fiery plunge through Earth's atmosphere.

The observatory is the latest victim of intense solar activity, which increases the drag on satellites in Earth orbit and makes it harder for spacecraft to stay aloft. Swift has been losing altitude for a while, but the final straw came in August, when a costly mission to boost Swift's orbit with a private spacecraft failed, ending with the would-be rescue craft burning up in the atmosphere after a series of hardware malfunctions.

Swift is now beyond saving and, orbiting at just 171 miles (275 kilometers) above Earth, can no longer take reliable observations of space. NASA expects the spacecraft to break up upon reentry "in the next few weeks."

NASA knew Swift was in trouble when it went in; soon, it'll be lying on the cold hard ground. However, the Swift mission surpassed its goals by decades. According to NASA, the satellite launched in November 2004 on a primary mission intended to last just two years. In the end, Swift survived for 22 years, surpassing its intended lifespan by more than 10 times.

In that time, Swift made thousands of observations of exploding supernovas, intense gamma-ray bursts, and black-hole-related episodes of stellar destruction, contributing data to about 7,000 scientific papers, according to NASA.

Designed as a multiwavelength observatory, Swift watched the sky in optical, ultraviolet and X-ray light that made it well suited to track the aftermath of powerful energy bursts. Its greatest asset, perhaps, was its rapid response time; if an explosion flashed somewhere in the sky, engineers could swivel Swift to study it within minutes, NASA said.

"Swift was designed as a satellite dedicated to studying gamma-ray bursts, outbursts that came and went so quickly that no one could target them with large telescopes to learn more," S. Bradley Cenko, the mission's principal investigator at NASA's Goddard Space Flight Center, said in the statement.

Swift's fast-acting observations "played a major role in advancing our understanding of the changing universe and was part of a revolution in astrophysics," added Shawn Domagal-Goldman, director of the Astrophysics Division at NASA headquarters.

A neglected "ghost particle" may have dominated the universe right after the Big Bang ‪—‬ changing how the cosmos expanded in its first moments and reshaping the conditions under which matter won out over antimatter, a new study suggests. In other words, it may explain why anything exists at all.

The particle, a hypothetical "right-handed" neutrino, briefly could have held more energy than everything else in the infant universe combined, which would have sped up cosmic expansion and delayed key particle interactions, the study proposes. The research was published Sept. 8 in the journal Physical Review Letters.

Neutrinos are ghostly particles that rarely interact with anything. A typical neutrino from the sun could pass through a slab of lead a light-year thick — about 5.9 trillion miles (9.5 trillion kilometers) — before striking a single atom. Neutrinos come in three types, or "flavors," and switch between them as they travel, making use of a subtle quantum effect that works only if they have mass. Yet the Standard Model of particle physics predicts they should be massless.

One popular fix involves "right-handed" neutrinos. Particles spin a bit like tiny tops, and physicists call them left- or right-handed depending on how they spin relative to their direction of travel. A right-handed particle rotates like an ordinary screw being driven in, turning clockwise as it moves away from you. Every neutrino detected so far is left-handed and turns counterclockwise as it flies away, like a screw with a reverse thread.

"Right-handed neutrinos are hypothetical particles that do not feel the weak nuclear force, "unlike their left-handed counterparts, which are part of the Standard Model," study co-author Rishav Roshan, a theoretical physicist at the University of Southampton in the U.K., told Live Science via email. "They are characterized by having no electric charge and being much heavier."

"Right-handed neutrinos may mix with left-handed neutrinos, helping to explain the mass of the latter" and why they switch flavors, Roshan said.

The cosmic seesaw

In quantum physics, particles that mix can exist as a blend of two identities at once. In a theoretical framework called the seesaw mechanism, each ordinary neutrino carries a faint trace of a heavy right-handed partner, and that trace gives it a tiny mass. The heavier the partner, the fainter the trace and the lighter the ordinary neutrino — hence the name, after the playground ride whose ends move in opposite directions.

The particles could solve other puzzles, too. They "aim to address several issues, including the origin of neutrino masses, the matter-antimatter asymmetry of the universe, and the nature of dark matter," Roshan said.

The Big Bang should have made equal amounts of matter and antimatter, which would have annihilated each other, forbidding the universe as we know it from ever taking shape. Right-handed neutrinos play a crucial role in models' proposals that the "observed matter-antimatter imbalance arose from processes involving these neutrinos in the early universe," Roshan said.

In this picture, decaying heavy neutrinos left behind a slight excess of leptons — the particle family that includes electrons — that later became today's surplus of matter, he explained.

The seesaw framework usually includes three right-handed neutrinos, but because two are enough to explain the data, physicists often ignore the third, assuming it is too heavy or interacts too feebly with matter.

How the heaviest neutrino took over

In the new study, Roshan and Sudipta Show, a physicist at the Indian Institute of Technology Kanpur, examined what this neglected particle — which, in the team's main example, was about 100 trillion times as heavy as a proton — would have done after the Big Bang.

At first, the particle would have zipped around at nearly light speed, so its energy would have faded like that of light, which would have both spread out and stretched to weaker wavelengths as space expanded. But as the cosmos cooled, the particle would have slowed down and most of its energy would have become locked in its mass, which would have been only spread out. Its share of the cosmic energy therefore would have grown until it dominated, and the long-lived particle would have stayed in charge until it decayed into other particles, according to the team's computations.

The study reveals that the neglected right-handed neutrino "significantly impacts the early universe's expansion dynamics, driving a period of early matter domination," Roshan said. This change "affects various Standard Model interactions"‬ that could help to explain the matter-antimatter asymmetry, Roshan added.

Each interaction would have switched on only once it outpaced the expansion of space. Because a universe dominated by the heavy neutrino would have expanded faster, the interactions would have had to wait until it cooled further.

These interactions would have let the early universe distinguish lepton flavors, which would have affected how the matter surplus formed. Thanks to the delay, the team found, a lighter right-handed neutrino about 100 billion times as heavy as a proton could have produced the observed amount of matter before the flavors could be told apart — even after the heavy neutrino's decay diluted part of it.

Hard to test, but not out of reach

The heavy neutrino is far too massive to create in any particle accelerator, so tests must be indirect.

Gravitational waves — ripples in space-time — offer one such route. An era dominated by the heavy neutrino would have left a telltale kink in the background of early-universe gravitational waves, such as those from "cosmic strings" ‪—‬ hypothetical thread-like defects in space. The results can be tested through forthcoming facilities such as the Laser Interferometer Space Antenna (LISA) and the Square Kilometer Array Observatory (SKAO), Roshan noted.

LISA, a space-based European Space Agency mission, is scheduled to launch around 2035, while SKAO, a giant radio telescope project being built in Australia and South Africa, could catch such waves by timing distant pulsars. Tests could come "as these facilities come online and begin data collection," Roshan said. A faint hum from the hot primordial plasma would carry the era's imprint too, but at frequencies beyond what existing detectors could pick up.

There's a new type of landslide affecting northern latitudes, and it could affect more areas as the planet continues to warm.

These landslides, called permafrost detachment slides, occur in areas with relatively thin permafrost and seem to be a long-term impact of wildfire in these environments, according to a paper published Sept. 23 in the journal Geophysical Research Letters. Such slides have not been observed in the region before and may be unprecedented over the past 10,000 years or more, said study leader Joseph Young, who completed the work as part of his doctoral degree at the University of Alberta.

"It has been stable, and then it just flipped a switch, essentially," Young told Live Science.

Young and his colleagues were doing field observations in Canada's Northwest Territories when they noticed large landslide scars in valleys that have long hosted stable permafrost, which is sediment that remains frozen year-round. They began using satellite imagery to map the changes and also conducted fieldwork, which revealed that the slides weren't standard melting permafrost.

"Typically with permafrost, everything just thaws and melts in a slurry and moves like a mud downslope," Young said. "But with these large landslides, we found blocks of frozen material in the debris."

Some of these blocks were 33 feet (10 meters) tall, the height of a two-story house. The researchers ran an electrical current through the ground to determine the depth of the permafrost on the slopes.

They focused on two slides. One, in the Johnson River Valley, took place in 2017 and moved more than 636 million cubic feet (18 million cubic meters) of soil and rock. The other, in the Redstone River Valley, moved almost 159 million cubic feet (4.5 million cubic meters) of debris in 2018. The smaller slide left a scar three-quarters of a mile (1.2 kilometers) long, while the larger one gouged nearly 2 miles (3.2 km) out of the hillside.

The researchers then used the data they'd collected to build a model of how these icy slides occurred. The permafrost in this area has been warming by about 0.54 degrees Fahrenheit (0.3 degrees Celsius) per decade since 1980, when monitoring began, and there were also severe wildfires nearby in 1995.

The researchers found that instead of a top-down melting process by which the permafrost thawed to a muddy slurry from above, the slides were instead caused by a combination of fire-related thaw and warming temperatures, leading to cracks near the top of the slopes. These cracks allowed the thaw to penetrate deeper, eventually melting the bottom of the permafrost layer. This propagation can take 20 years to penetrate 66 feet (20 m), which is exactly what happened in the Johnson River and Redstone River valleys.

"We had a fire in '95 and then 20 years later, we start to get a lot of these widespread disturbances," Young said.

The two large slides the researchers studied are among more than 150 in the area, Young said. The others are smaller, but they still typically move over 35 million cubic feet (1 million cubic meters) of land apiece. Canada's Northwest Territories are remote, so the permafrost detachment slides have yet to damage any infrastructure. But the two in the study did dam rivers, creating brand-new lakes and rapidly dumping sediment into the waterways downstream, Young said.

There are many other places in Canada and Alaska where the permafrost is 66 to 130 feet (20 to 40 m) deep and thus vulnerable to the same type of slide. This is especially true given the increasing intensity of wildfire at northern latitudes, Young said.

"This is almost a potential glimpse into the future of what we might be able to expect in these areas with changing forest fire dynamics," he said.

More children, teens and very young adults are being diagnosed with colorectal cancer in the United States, and new research suggests they often experience aggressive forms of the disease.

While diagnosis rates are rising, the disease is still rare among young people. Colorectal cancer, which affects the lower intestines and rectum, is largely a disease of age: 55% of all colorectal cancers are diagnosed in people over 65, and only 16% occur in people ages 49 or younger, according to a 2026 study published in the flagship journal of the American Cancer Society. Only a few hundred cases per year are diagnosed in people under age 21 in the U.S.

Nevertheless, the numbers of cases in the very young are rising, even as colorectal cancer rates decline or hold steady in older individuals. This increase coincides with an overall rise in colon and rectal cancer rates in people under 50.

The reasons for this schism aren't entirely understood. People over 50 receive routine colonoscopies in which precancerous polyps are removed, and that likely accounts for much of the decline in colorectal cancer diagnoses in older adults. But researchers suspect that environmental factors, such as ultraprocessed foods and sedentary lifestyles, might be behind the growing rates in young people.

"Most of the research has really focused on the gut microbiome," the community of bacteria and other microbes that live in the gut, said Dr. Christopher Lieu, a professor of medical oncology at the University of Colorado Anschutz and a medical adviser to the nonprofit Colorectal Cancer Alliance.

Microbiome disruptions may spur inflammation, which, in turn, may trigger DNA mutations that cause cancer. But these mechanisms are complicated, Lieu told Live Science, and there likely isn't one simple reason young people's microbiomes may be getting disturbed.

"It's going to be extraordinarily more complex than that," he said.

Aggressive disease in young people

What researchers are starting to learn is that colorectal cancer in people in their early 20s or younger tends to be a more aggressive disease than that often seen in older people.

"We do feel like it is a bit of a distinct disease than what we're seeing in older adults," said Dr. Erica Arnold, a pediatric surgery research fellow at Nationwide Children's Hospital in Columbus, Ohio. In October, Arnold presented new research on colorectal cancer in people ages 21 or younger at the annual meeting of the American Academy of Pediatrics.

Arnold and her colleagues analyzed the cases of 84 patients diagnosed between 2012 and 2023. They found that the median age of diagnosis was 16 years old and the median duration of symptoms before diagnosis was only 12 weeks long.

Only about 20% of the patients had a close relative with colorectal cancer, suggesting that for many of these young people, the disease did not necessarily emerge due to hereditary factors.

Eighty percent of the study participants were diagnosed with Stage III or Stage IV disease, meaning the cancer had already spread locally and to lymph nodes or to other, distant organs when the patients were diagnosed. For comparison, in colorectal cancer patients of all ages, 60% are diagnosed in Stage III or IV, according to the Centers for Disease Control and Prevention (CDC).

In addition, Arnold said, one-third of the patients in their study had cellular markers of particularly aggressive cancer.

"Some of that might be related to delays in diagnosis," Lieu said, "but if you want my honest opinion, it does suggest that these cancers are developing differently."

The study's data was not nationally representative, but a recent analysis of CDC data has also found that colorectal cancer rates in youth are on the rise. In 1999, the diagnosis rate in kids ages 10 to 14 was 1 in a million. By 2020, it had risen to 6 in a million. For teens between 15 and 19, the rate of diagnosis went from 3 in a million to 13 in a million in that same time frame.

Unclear causes

There is no definitive reason for this rise, Lieu said. Research on the microbiome has suggested that processed food, antibiotic exposure in childhood, stress, reduced exercise and other lifestyle factors may contribute to this increased risk of colorectal cancer.

Some microbes may play a particularly strong role, at least in some cases of colorectal cancer. For instance, a specific variant of the common gut bacterium Escherichia coli is strongly associated with colorectal cancer; the variant carries a genetic segment and produces compounds that are toxic to genes. But this variant alone cannot explain all colorectal cancer cases in young people. Nor is it clear why the gut microbiome might be undergoing a shift in the first place.

"It may be a combination of food, antibiotic use and environmental exposures," Lieu suggested.

Regardless of the exact causes behind the cases, Arnold's new research pointed to the symptoms that deserve closer scrutiny in young people. Among the 84 patients in the study, 75% reported experiencing back and abdominal pain before their diagnosis, 45% had changes in their bowel movements, 43% experienced unexplained weight loss and 38% had rectal bleeding.

These are classic colorectal cancer symptoms, Arnold said, but they might be overlooked in this young age group because these same symptoms can have more common causes.

Parents should know that in most cases, stomach pain and gastrointestinal disruptions in kids are not caused by colorectal cancer, Lieu said, calling the cancer an "extraordinarily rare event." Nevertheless, pain or gastrointestinal upset that doesn't ease or that worsens over time needs a checkup, and symptoms like weight loss and blood in the stool are very unusual in kids and deserve extra attention.

"It's just important to investigate it to make sure we're catching colorectal cancer earlier rather than later in these patients," Arnold said.

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

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Archaeologists in Peru have found an elaborate 1,500-year-old tomb that may hold the remains of a high-status toddler from a pre-Inca civilization.

The burial, which is from the Moche culture, also contained vessels depicting prisoners with rope around each of their necks and a sculpture of a human-bird deity.

Moche (also known as Mochica) culture developed along the northern coast of what is now Peru from the third to the ninth century. They created agricultural lands in the region's desert landscape, and their archaeological record includes monumental temples, water canals, pottery, metallurgy, textiles and a distinctive form of art. The Moche didn't have a written language, but they left behind thousands of realistic portrait vessels, which are somewhat similar to the prisoner sculptors found in the toddler's burial.

In the newfound tomb, the team unearthed a small skeleton, which is likely the remains of a toddler who was, at most, 2 years old, Carlos Rengifo-Chunga, director of the University of Trujillo's Huacas de Moche Archaeological Project, told Live Science. The child's sex is unknown.

Rengifo-Chunga and his colleagues also found two copper objects in the burial: a mask-like disk covering the child's face, and a half-moon object on their feet. In addition, the burial contained 32 ceramic objects associated with Moche culture, including those depicting the prisoners and the deity.

The tomb was large compared to the child's small size, and could have easily held an adult, Rengifo-Chunga said. It dates to the sixth or seventh century, he added.

The team unearthed the tomb inside the Uhle Platform at the Huacas de Moche archaeological site in northern Peru. The Uhle Platform is a mausoleum, attached to the Huaca de la Luna temple, with a patio archaeologists call the Patio of the Serpents. Of the more than 80 burials previously uncovered there, the tomb represents the only known child to receive this sort of lavish burial.

The elaborate funerary treatment, including the use of copper, and the location of the tomb all suggest that the child belonged to an elite class of Moche society, Rengifo-Chunga said.

The two prisoner sculptures are associated with the "ritual of combat," a common theme in Moche art. In this sort of imagery, two warriors fight each other, and the loser is stripped of his clothes and weapons, tied around the neck with a rope and offered as a human sacrifice, Rengifo-Chunga said. The prisoners depicted on these two vessels were the losing warriors, and their presence in the burial of a child is rare.

"One would normally presume that these kinds of vessels represent something related to the deceased's life," Rengifo-Chunga said. For example, a vessel like this might signify that the individual took part in combat.

But a toddler couldn't have taken part in such an activity. In general, archaeologists wouldn't expect to see elements of an adult ritual in the burial of a child. "This expands our knowledge on Moche funerary practices," he added.

The sculpture of the presumed deity depicts a human body with bird wings and a bird tail, although for some scholars it might be interpreted as a god in transformation, Rengifo-Chunga said. The deity holds a square shield in one hand and a goblet in the other, and is flanked by two bird "assistants" wearing ceremonial garments.

Researchers will have to investigate whether the deity is a known Moche god, or a newfound addition to the pantheon. Either way, the object joins a contentious debate over whether the Moche pantheon consists of many gods, or just a few that can transform into many different versions, Rengifo-Chunga said.

The artifacts are now in the laboratories of the Santiago Uceda Castillo Museum in Peru, where they will undergo conservation treatment.

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

In 1833, stone quarry workers discovered an ancient burial mound at Goblins' Hill near the town of Mold in Wales. At the center was a stone-lined grave that contained a fragmented skeleton and a gold, cape-like accessory that had been crushed over time. The Mold gold cape has a unique shape and style, and it is one of the finest examples of prehistoric goldwork ever found, according to the British Museum, where the artifact is on display.

The cape dates to Britain's Early Bronze Age (2500 to 1200 B.C.), a time that saw a metalworking revolution as artisans shifted from crafting flint tools to making weapons and jewelry out of gold, copper and bronze.

When the cape was originally unearthed, experts assumed that it had belonged to an ancient warrior, chief or religious leader, due to the spectacular design of the object, Benjamin Roberts, then curator for the European Bronze Age collections at the British Museum, told the BBC in 2010. But after the broken pieces of the cape were put back together, the small size of the artifact suggested it may have been worn by a woman or a child.

The Mold gold cape measures roughly 9.3 inches (23.5 centimeters) tall and 18.3 inches (46.5 cm) wide. It weighs about 1.2 pounds (560 grams) and was probably crafted from a single lump of gold about the size of a ping-pong ball.

The gold ingot was beaten incredibly thin, fashioned into a cape, and then embellished with decorations that mimicked beads or necklaces, according to the British Museum. Additionally, several hundred amber beads were found on the cape in the grave, which likely added to the gilded appearance of the accessory. Perforations around the neck opening suggest the cape originally had a lining made of leather or another perishable material that did not survive.

Because the gold cape, when worn, would restrict a person's upper arm movements, it may have been a ceremonial accessory that conferred religious authority and was worn only on special occasions. But experts are still unsure why the cape was buried in a grave. Nor can they confirm whether the person it was interred with was male or female, as the skeleton was not recovered by the quarry workers in the 19th century.

"The cape is unique — there is really nothing to compare it to in the whole of Europe," Roberts told the BBC. "This makes it more difficult to understand why it was made and what significance it had."

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

Can you put together last week's Astonishing Artifact?

People who rely on artificial intelligence (AI) to solve simple problems do worse at, and are more likely to give up on, similar tasks when that assistance is removed, compared with people who do not use AI for quick answers, new research finds.

The study, which was presented at the 2026 Conference on Language Modeling in San Francisco earlier this month, investigated the impacts of shifting mental work onto an AI chatbot across arithmetic and reading comprehension tasks. A growing body of research suggests this process of "cognitive offloading" harms long-term learning and critical thinking abilities.

"The concern is about what cognitive scientists call 'desirable difficulties' — the productive struggle that builds skill over time," study first author Grace Liu, a doctoral student in machine learning at Carnegie Mellon University, told Live Science in an email. "If AI routinely removes that struggle, people may get the right answer in the moment but develop less robust independent capability."

Liu and her colleagues recruited 1,222 participants for the study, which was released as a preprint earlier this year and has now undergone peer review. The researchers designed three randomized controlled experiments, including two sets of mathematical fraction problems and a series of reading comprehension questions. The participants were split into three groups, so there was no overlap between the experiments. Each experiment took 13 to 15 minutes to complete.

In the first experiment, the team randomly assigned 354 participants to two groups: one that had access to an AI chatbot and one that didn't. The researchers gave both groups the same 12 fraction problems, which the AI group could get the answer to immediately or obtain clues about by prompting the chatbot. Then, the researchers removed the AI assistant without warning for a final set of three fractions, which all of the participants were given, regardless of their group.

Both groups had the option to skip problems. The researchers explicitly told the participants that there was no penalty for wrong answers, so skipping a problem was a deliberate decision to not engage with it, they wrote in the study. The participants in both groups were also given the correct answer to each problem if they got it wrong, so they could learn from their mistakes.

This first experiment showed that the participants in the AI group were more likely to solve fractions and less likely to give up when they had access to the chatbot compared with the other group. But when the AI was removed, their performance dropped and they skipped or failed more problems, suggesting that using AI impaired unassisted task performance, persistence and motivation.

The second experiment was a copy of the first experiment, but it had 667 participants and small tweaks in the trial design, including the addition of a pretest phase that helped the researchers eliminate participants who were unable to solve the most basic problems. The findings were similar to those of the first experiment, hinting that the use of AI for simple tasks harms perseverance and drive to complete those same tasks without AI, especially when AI is used to get direct solutions.

Liu acknowledged that calculators also allow people to offload computations, which could cause similar declines in independent performance. But "the reason we study AI specifically is that it allows people to offload reasoning across tasks across many domains," she said.

In a third experiment, the team explored the impacts of AI assistance on reading comprehension, which draws on meaning-making skills and mental-model construction — the cognitive process of building internal representations of external reality. The trial included 201 participants, who were divided into a group with access to AI and a control group. The researchers gave both groups five comprehension questions before disabling the AI chatbot and handing each participant another three questions.

The results mirrored those of the first two experiments, suggesting that reduced persistence, in particular, was not an artifact of the math problems but a general outcome of cognitive offloading onto AI.

"The most significant finding is that people who offload more have higher declines in persistence (increased skip rate), which is an important skill that cuts across domains," Liu said.

One possible reason people stop trying once they have experienced help from AI is that they get used to the immediacy of answers and perceive any method that takes longer as inefficient, the researchers wrote in the study. But studies show that persistence through difficulty is essential for skill acquisition and learning, raising concerns about the long-term impacts of using AI for simple tasks.

Scientists don't yet have a full picture of how small instances of cognitive offloading affect lasting competence and independent ability. To find out, researchers would need to track the same people for a long time and regularly measure their learning outcomes across a wide range of tasks, Liu said. But research so far suggests that an overreliance on AI erodes our cognitive fitness and mastery of subjects, according to the study.

To encourage long-term learning, capability and autonomy in people, AI models and chatbots should be designed to give directions and instructions toward a solution, rather than the solution itself — more like a tutor, the researchers argued.

"We need to work toward a future in which human abilities are, as much as possible, augmented rather than supplanted," study co-author Brian Christian, a computer scientist and researcher in the Center for Human-Compatible AI at the University of California, Berkeley, said in a statement.

When a seagull stares you down, scientists recommend that you stare right back at it to keep your dignity (and your french fries) intact.

Two years ago, astronomers at the Vera C. Rubin Observatory put this idea — and their brand-new telescope — to a test of cosmic proportions, aiming an experimental 144-megapixel camera at the menacing blue eye of the Seagull Nebula (IC 2177).

Located about 3,700 light-years from Earth, the Seagull Nebula is a conglomeration of three giant, billowing clouds of irradiated gas. The "head" of the bird, featured in Rubin's image above, is a cloud called Sharpless 2-292. Its pink plumage is made of hydrogen gas, which glows brightly as ionizing radiation flies forth from the young stars at the cloud's center. The bird's blue "feathers" are clouds of dust reflecting the light from young, blue stars nesting elsewhere in the region.

It's unclear who won this stellar stare-down. If the bird appeared to blink, that's only because its eye is really the triple-star system HD 53367, a flickering trio of very young and energetic stars actively shaping the cloud around them.

The Rubin Observatory, meanwhile, had to avert its gaze quickly; this image is just one of about 16,000 exposures taken of the night sky between Oct. 24 and Dec. 11, 2024, according to the National Science Foundation, which co-manages Rubin along with the U.S. Department of Energy. Taken with the aforementioned Commissioning Camera (ComCam), the deep-space photos served as an early test of the observatory's hardware, software and image-processing capabilities.

ComCam's test image is remarkably crisp — but what's even more impressive is that Rubin has since upgraded to a camera with more than 20 times the field of view. The Legacy Survey of Space and Time Camera currently mounted on the observatory's Simonyi Survey Telescope takes 3,200-megapixel images of the night sky every 30 seconds, completing a full scan of the entire southern sky every few nights, Tony Tyson, Rubin's chief scientist, previously told Live Science.

Now that the Legacy Survey of Space and Time has officially begun, Rubin will spend the next 10 years photographing the sky night after night, creating a time-lapse movie of the universe that is expected to reveal millions of cosmic wonders, from exploding supernovas to newfound comets and exoplanets. Perhaps it will even spot another bird.

Like what you see? Take a look at the hidden details in the Vera C. Rubin Observatory's debut images here.

In the 17th and 18th centuries, the fear of vampires reached extraordinarily heights. People believed corpses could reanimate and wander around, terrorizing villages and spreading disease. They went to extreme lengths to prevent a vampire from rising. Some chopped the deceased person's head off, others placed sickles across their necks. Many were placed face down in their graves. In one grave in Poland, the remains of a boy were found with an iron padlock around his foot.

In this excerpt from "Killing the Dead: Vampire Epidemics from Mesopotamia to the New World" (Princeton University Press, 2025), author and historian John Blair reveals the impact the printed press had on the spread of vampiric lore — and the grizzly purported practice of ingesting the blood and organs of a vampire to prevent other people becoming one.

With the invention of printing, the circulation of European stories about restless corpses moved up several gears. Occasional early references were followed by a clutch of theological and philosophical discussions during c. 1580-1610, and then — from the 1670s — a steadily growing volume of printed academic and historical debate and commentary, reaching a climax in 1732.

Another landmark came in 1746 when the Benedictine scholar Dom Augustin Calmet published his survey of supernatural beings, which was quickly reissued in several editions, including an English one of 1759. This book's section on vampires was the most influential academic work on the subject ever published. Its straightforwardly evidence-based approach was a breath of fresh air after a long series of increasingly derivative works.

It achieved its remarkable popularity because it entered the market at the right point: saturated with so much fragmented and repetitive discussion of "vampires" (still a relatively new word), the reading public wanted a textbook. Calmet inspired a huge progeny of followers and popularisers, bringing the stories to a much wider readership; a good example of the genre is the Histoire des vampires et des spectres malfaisants [History of Vampires and Malevolent Specters] of 1820, a pocketbook that re-packages Calmet for the mass market.

Calmet's book remains the ultimate source of much modern vampire literature in Europe and America, both fi­ctional and supposedly historical, and was transformative in bringing the topic to a wider reading public. There and elsewhere, stories were now frozen on the printed page, where later generations could read them. But they were stories still: not necessarily more reliable, and by no means stable in transmission.

The complexity of interactions between learned discourse and popular practice is illustrated by one particularly bizarre and repellant (not to say dangerous) strand in the belief-system. This is the practice of ingesting blood or organs from a supposed vampire corpse, or ashes derived from burning them, as a remedy for vampire-induced illness.

Although not wholly dissimilar from the idea that victims will recover as they watch the smoke rise from burning vampire organs — already known in 11th-century England — its shocking physicality sets it apart. Did people in pre-modern Europe really do this?

A complicating factor is the medicinal use of human blood and bodyparts, in accordance with the theories of the physician, philosopher, and alchemist "Paracelsus" (Theophrastus von Hohenheim, c. 1493–1541). A brilliant experimenter, Paracelsus believed that substances healed through occult 'influences' or 'spirits,' the most powerful being those derived from what they were meant to cure: the human body.

The fact that medicine now rejects these hypotheses should not make us view them patronizingly: in the early modern period, ingesting or anointing with substances from Egyptian mummies or the blood of executed criminals seemed as rational as doing the same with any other substance. These Paracelsian ideas entered popular practice: at a beheading in Vienna in 1668/9, a man ran forward and caught the spouting blood to cure his epilepsy.

The tangled story of consuming blood from vampire corpses starts in a different and very unexpected place. In 1687, a major ethnographical account of parts of West Africa by the Capuchin missionary Giovanni Antonio Cavazzi was published in Bologna. In it, Cavazzi describes magical and medical practices among the Mbundu of Angola, including a method of obtaining vital curative fluid from undecayed corpses:

When they are in a fresh and intact state when unearthed, their heads are cut from their bodies, from which it is said that blood flows out (which may happen through some illusion or deceit). It is collected and made into poultices for the sick, or mixed into their food, which infallibly guarantees health. Thereafter the dead person, having lost his strength, will no longer be able to harass them.

From Angola to Paris: in May 1693, a story appeared in the society magazine Mercure Galant. The author was the courtier and polymath Pierre des Noyers (1607–93), who spent several years in Poland in the entourage of Queen Louise-Marie. Much earlier, in 1639, he had written to a friend about the being known as upior (Ruthenian) or striga (Polish): born with teeth; eating its shroud and then its hands and arms in the coffi­n; causing successive deaths of family members; and extinguished by decapitation and release of pent-up blood.

This story is rather highly coloured (eating the hands and arms is unusual), but it does probably originate in genuine oral accounts of the shroud-chewer belief.

Very different is des Noyers’s account from 1693. Now the striges and upierz have become corpse-hijacking demons: 'It is said that the demon takes this blood from the body of a living person, or from certain animals, and carries it into a dead body; for it is alleged that the demon goes out from this corpse during a certain period, between noon and midnight, after which it returns and stores there the blood that it has gathered.'

The blood comes out of the mouth, nose, and ears of the corpse, the corpse swims in blood, and it starts to eat its shroud. The demon especially troubles former associates and relatives of the dead 'host,' appearing to them in the guise of parents or friends, and does not leave until all the family members have died in succession. The remedy is to exhume the corpse, which is found soft, flexible, bloated, and red:

When they are found in that state, having the likeness of those who had appeared in dreams, their heads are cut off and their hearts are opened, and a quantity of blood flows out. It is collected and kneaded into flour, which is made into bread, which is a certain remedy to guarantee against such a terrible affliction. After the heads [of the dead people] have been cut off, those whom the Spirit torments at night are no longer troubled by it, and are well thereafter.

This narrative has problems. The idea of the demon using the corpse as a safe-deposit for its hoard of blood seems to be unique; so, probably, is the time-slot between noon and midnight. These read like clerical rationalizations, perhaps fed to des Noyers by some Polish priest and overlaid on his earlier, more authentic observations. But more fundamentally, it seems obvious that des Noyers’s account of Poland shamelessly re-works Cavazzi's account of Angola, published eight years previously.

It might not be quite so simple. An earlier common source, still unidenti­fied, remains possible. The descriptions of mixing blood into food and poultices look remarkably close to Paracelsian ideas, extended from ordinary corpses to undead ones: was even Cavazzi's account distorted by his own medical learning? But in any case des Noyers’s account is a piece of unprincipled plagiarism, worthless as evidence for Polish folk-belief.

Even so, it has bounced down through the echo-chambers of vampire literature ever since. The following year, a lawyer called Marigner built on the narrative — which he took at face value — with long philosophical musings on the nature of vampires. Inevitably, in 1746, it was republished in Calmet's book, which made it permanently available to vampire-aware readers.

While otherwise faithful to des Noyers, Calmet's version irons out the motif of demonic corpse-possession by calling this predator a vampire 'or a demon in its form.' This process of moulding to a more familiar template culminates in a recent version that presents the story as straightforward ethnographic reporting, omitting the demonic motif completely.

So far, this has just been a morality tale of plagiarism and uncritical copying. But in 1713, at Dąbrówka (now western Ukraine), some villagers were tried in the Uniate episcopal court for exhuming a woman's corpse and mutilating it in inventive ways. They admitted to the exhumation (because the dead woman had been walking around and attacking people), and to drinking the corpse's blood mixed with vodka. They denied cutting out the heart, mixing the blood into flour, and baking cakes with it, but the judges were sceptical and made them swear an oath.

This will sound very familiar to readers of early modern witch trials, where suspects were regularly bullied into admitting bizarre fantasies formulated by the persecutors. In this case, it seems clear that at least the idea of the blood-cakes was suggested by the judges; the same could be true of the blood-drinking, even though the accused were induced to confess that. It is distinctly possible, not to say likely, that an ordinary corpse-killing was embellished with luridly fi­ctitious detail by judges who knew des Noyers's report from twenty years earlier.

Killing The Dead: Vampire Epidemics from Mesopotamia to the New World. Copyright © 2025 by John Blair, published by Princeton University Press and reprinted here by permission.

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At nearly 10 feet (3 meters) tall and around 500 pounds (230 kilograms), Gigantopithecus was the largest primate that ever lived.

Foraging across the dense tropical forests of Southeast Asia between 2 million and 200,000 years ago, the giant ape may have shared the habitat with new arrivals — hominins such as Homo erectus. (Hominins are members of the group that includes modern humans, their ancestors and closely related species, after the evolutionary split from great apes.)

Despite their immense size Gigantopithecus mainly consumed plants and is closely related to modern-day orangutans.

So what would have happened when Gigantopithecus encountered these human ancestors?

Experts suggested a variety of possible scenarios, including that Gigantopithecus and human ancestors didn't encounter each other at all.

It's "very difficult to say with any certainty, as we have no direct evidence documenting interactions between Gigantopithecus and human ancestors," Renaud Joannes-Boyau, director of higher-degree research training at Southern Cross University in Australia and an archaeologist who has conducted extensive research into human evolution, told Live Science in an email.

"That said, if we look at the broader pattern of human evolution, our lineage [Homo] has consistently behaved as an apex predator," Joannes-Boyau said. "Humans and our ancestors have shown a remarkable tendency to explore, exploit and, at times, eliminate large animals that shared their environment. I think it is reasonable to imagine that those interactions may have involved a mixture of indifference, curiosity and violence, depending on the circumstances."

Friedemann Schrenk, a professor of paleobiology at Johannes Gutenberg University Mainz in Germany, thinks Gigantopithecus would have likely tried to avoid humans. "Humans were and are the most aggressive primates ever on earth using tools and weapons and were probably encroaching on Gigantopithecus habitats," he told Live Science in an email. Homo erectus made use of hand axes and possibly hafted spears.

Schrenk envisions the hypothetical interactions as similar to those between modern-day humans and orangutans, which has resulted in humans encroaching on orangutan habitats and the apes' populations declining. "After all, Gigantopithecus was a gigantic orangutan," he said, noting that if there was hostility in a direct encounter, early humans would have been the aggressors.

Different environments?

Yet it's also possible that Gigantopithecus and hominins lived in different environments in Southeast Asia, which would have minimized the number of interactions they had, said Hervé Bocherens, a professor of biogeology at the University of Tübingen in Germany.

The "carbon stable isotopic ratios measured on some teeth of both taxa suggest a different habitat, closed forests for Gigantopithecus and open savannah for Homo erectus," Bocherens told Live Science in an email. However, because of limited data, "we cannot exclude that some hominins were also present in more forested environments," he added. Grinding patterns in their teeth suggest that Gigantopithecus' diet was essentially plant-based and may have included bamboo.

In a 2024 study, scientists investigated the demise of Gigantopithecus and found no evidence that hominins contributed to Gigantopithecus' extinction. Instead, they determined that the main cause was environmental change that resulted in a reduction in the forested environment where Gigantopithecus lived and foraged. In fact, hominins and Gigantopithecus may not have encountered each other at all, Yingqi Zhang, a researcher at the Chinese Academy of Sciences and first author of the paper, told Live Science in an email.

We can only imagine what hominins would have thought when they glimpsed these gigantic creatures. It’s not clear how hominins and Gigantopithecus would have interacted, if they ever did, said Frido Welker, a professor of biomolecular paleoanthropology at the University of Copenhagen. He thinks they would have avoided each other but they may have "been in awe when they did happen to run into each other."

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

The largest artificial intelligence (AI) firms increasingly understand that they are hostages of one another. If one firm pushes ahead recklessly, others may feel compelled to follow. If one deploys a dangerous model without adequate safeguards, others may see it as a green light to do the same.

The debate over AI has centered on what governments should do to regulate this frontier technology. That remains essential. But a more immediate question is emerging: Can the companies building these powerful systems take action independently before they lose credibility and suffer legal consequences?

That question no longer looks theoretical and is being recognized as an urgent challenge. We've already seen AI firms lose control of their models — for example, in Australia, a rogue AI hacked a government healthcare website. If we are not careful, it's only a matter of time before one of these incidents causes large-scale, real-world harm, like shutting down an electricity grid or municipal water system, or a mass misdiagnosis in a health system. If this trend continues, the entire industry could become tarnished.

But there is a blueprint for self-regulation in a risky business: the nuclear industry, which has built up layers of oversight, controls and self-scrutiny over decades.

Frontier AI may require something similar: private regulation among competitors that do not trust one another but have a mutual interest in preventing outcomes that could damage them all. This does not appeal to the better angels of human nature — it's self-preservation for the industry itself.

There is a historical precedent for this kind of arrangement. The nuclear sector did not become safe because every actor suddenly became benevolent. It became safer through a layered system of peer scrutiny, technical standards, information-sharing and external oversight. International organizations such as the International Atomic Energy Agency (IAEA), which was established in 1957, emerged to coordinate monitoring and verification, while national regulators and industry bodies gradually built professional norms around catastrophic risk.

The result was not perfect safety, as the Chernobyl disaster in 1986 clearly attests. But nuclear governance architecture is designed around the recognition that in high-risk technological systems, one actor's failure can become everyone's problem. This was seen following Chernobyl: global nuclear safety increased significantly after the disaster, with upgrades to reactor designs, improved training and international monitoring networks.

And this movement to self-regulation also occurred in the U.S. nuclear sector, following the Three-Mile Island nuclear accident near Harrisburg, Pennsylvania, in 1979. The reactor suffered a partial meltdown after a relatively minor cooling malfunction. Investigations later revealed design flaws in instruments and alarms, along with inadequate emergency response training, were the root cause of the incident.

The event nearly killed the nuclear energy industry in the U.S., causing public support to fall from a record high of 69% in 1977 to 46%t in 1979. The entire industry suffered because of failures at one facility. In response, the U.S. nuclear industry established the Institute of Nuclear Power Operations (INPO) in December 1979 to improve operational safety.

The analogy to AI should not be overstated. Nuclear materials are easier to count than algorithms, and nuclear facilities are harder to hide than model weights. The outcomes of a catastrophic AI blunder are also less existential, although its use in weapon systems is not without risk. In September, an AI hallucination almost led to the U.S. intercepting a Chinese ship suspected of carrying nuclear material to Iran.

Yet the comparison remains useful because the core governance problem is similar. In both cases, competitors operate in an environment where the downside risk of unchecked rivalry is borne by society while the upside is private gain for these firms. The challenge is to create institutions that make restraint the rational default — even when no actor fully trusts the others, and the inner workings of the industry are not readily visible to outsiders.

For AI, that could mean reciprocal evaluation of frontier models before deployment, secure mechanisms for sharing safety information, agreed red lines around certain capabilities, and independent third parties empowered to audit compliance. Such mechanisms would not replace government regulation. They would instead serve as an intermediate layer: stronger than voluntary ethics statements but more adaptive and technically informed than legislation alone can often be in fast-moving domains. The state would act as a background enforcer.

AI executives appear willing to look for solutions too, with Elon Musk recently suggesting a peer-review system before advanced model release, and Demis Hassabis, co-founder and chair of Google DeepMind, putting forward a framework for an AI Standards Body, similar to the Financial Industry Regulatory Authority.

Skeptics will object, with reason, that industry-led governance can become cartel behavior or public-relations theater. Companies may use "safety" language to entrench incumbency, slow rivals or deflect binding regulation. Those are real dangers. The lesson from nuclear history is not that private coordination works automatically. It is that private coordination works only when nested inside a broader system of transparency, verification and public authority. Without those elements, private regulation becomes little more than trust-me rhetoric.

Still, dismissing private regulation altogether would be a mistake. Governments do not yet possess the technical capacity, speed or international alignment needed to oversee frontier AI on their own. And if the leading labs already see themselves as bound together by shared exposure to catastrophic risk, that recognition can become the basis for institutional design. The question is how to turn mutual fear into durable rules.

That is where the nuclear analogy is most powerful. It reminds us that industries facing existential hazards do not need perfect trust in order to cooperate. They need mechanisms that make cooperation preferable to defection. In practice, that means inspections, peer review, incident reporting, professional norms and a state-backed enforcement perimeter. AI governance is often discussed as if the only choices were laissez-faire innovation or heavy-handed state control. History suggests a third path: structured private coordination under public shadow.

The real opportunity, then, is not to celebrate the newfound (apparent) prudence of technology executives, it is to recognize what their comments reveal. When even fierce rivals begin to argue for mutual scrutiny, they are admitting that competition alone cannot govern the frontier. That admission should be treated not as reassurance but as evidence that the risk has become collective.

The policy task now is to build institutions that fit that reality. Governments should push for mandatory reporting, independent evaluation and legal backstops. But they should also encourage enforceable forms of peer oversight among the handful of firms whose systems may shape the trajectory of the technology. Frontier AI is becoming an industry in which the leading actors are hostages of one another. The nuclear age showed that such conditions can produce serious governance. The hope is that AI firms learn that lesson before they learn the cost of ignoring it at the peril of the public at large.

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October's full "Hunter's Moon" is about to rise, and skywatchers will get two great chances to see it appear on the eastern horizon around sunset.

Although it officially turns full at 12:11 a.m. EDT on Monday (Oct. 26), the Hunter's Moon will appear almost perfectly full as it rises on both Sunday (Oct. 25) and Monday evenings, giving skywatchers two opportunities to observe it.

October's full moon is nicknamed the Hunter's Moon because it was traditionally a signal for hunters to prepare for the coming cold winter by hunting, slaughtering and preserving meat, according to Time and Date. That's an Anglo-Saxon name; Native American names for October's full moon include the Drying Rice Moon, the Falling Leaves Moon and the Freezing Moon.

The first chance to see the Hunter's Moon comes just before sunset on Sunday, when the almost-full moon will rise in the east. The second opportunity comes on Monday, when the moon — still essentially 100% illuminated — will again rise just after sunset. Because it will be in a slightly darker sky, Monday's moonrise will likely be more dramatic.

As it rises Sunday, the moon will appear in the constellation Aries, and Saturn will be to its upper right. On Monday, it will rise above the Pleiades open cluster (M45).

For the best view on either evening, find somewhere with a clear view low to the eastern horizon and be in position shortly before moonrise where you are. An elevated viewpoint, open field or coastline is ideal because buildings, trees and hills can delay the moment the moon becomes visible.

Although the full moon will look magnificent with the naked eye, a backyard telescope or good stargazing binoculars can help you zoom in on various lunar features.

The Hunter's Moon may appear unusually large thanks to the "moon illusion," which makes the moon seem bigger when it's seen beside familiar objects, such as trees and buildings, near the horizon. The illusion stems from the fallacies of how our brains use distance to perceive size.

October's Hunter's Moon isn't a supermoon, but it comes immediately before a notable sequence of four consecutive supermoons. The first will be the next full moon, the Beaver Moon, on Nov. 24, followed by full moons in December, January and February. A supermoon occurs when a full moon happens while the moon is relatively close to Earth in its slightly elliptical orbit, making it appear somewhat larger and brighter than average.

How much do you know about the moon? Test your lunar smarts with our moon quiz!

The Nazca Lines are the most famous geoglyphs in the world. Dating back around 2,000 years and reaching a combined length of more than 800 miles (1,300 kilometers), they depict a variety of motifs, including humans, animals, geometric shapes, plants and flowers. These designs were constructed on the arid hills and valleys of coastal Peru by the Nazca people between 200 B.C. and A.D. 500, long before writing was used in the region.

It's not clear exactly how many Nazca Lines there are, but they number in the thousands, with new geoglyphs continuing to be discovered with the help of AI.

But why were the Nazca Lines built?

Scientists have been debating this question since the lines were first formally investigated in the early 20th century. Although the definite answer remains unknown, experts have proposed various reasons for the famous geoglyphs.

There "are many ideas out there about their function and meaning," Ana Nieves, a professor of art history at Northeastern Illinois University, told Live Science in an email. "If you look at the area's geoglyphs closely, though, there are different styles of geoglyphs, some are relatively larger and some smaller, some are on hillsides while some are on the pampas. It is not likely that a single explanation would apply to all."

Different perspectives

A vast array of theories for the lines' uses have been proposed over the years, with the most outlandish of these suggesting that they were sites for aliens to land spaceships.

More grounded theories link the lines to cultural and religious practices.

"The question of why the geoglyphs exist is difficult to answer, given that we lack any type of preserved oral or written testimony," Karsten Lambers, an art history professor at the University of Augsburg in Germany, wrote in an essay published in the book "Los geoglifos: imágenes y escenarios en el desierto de Nazca y Palpa [The Geoglyphs: images and settings in the desert of Nazca and Palpa]" (University of Augsburg, 2017). It's possible that the uses for the geoglyphs changed over time, he added.

One suggestion is that they were initially used to mark routes for travelers and caravans and later became places for gathering and feasting.

In a 2026 study, researchers noted that some of the earlier Nazca geoglyphs were constructed on hillsides, seem to be located on trails, and "were visible from considerable distances." This means the geoglyphs may have been used to mark travel routes and indicate areas that were good for temporary camps. The team suggested that the markings became places for gathering and feasting.

Another idea is that the geoglyphs were used to match astronomical alignments to serve as a kind of calendar. In December 1941, historian Paul Kosok examined the lines and determined that they had astronomical alignments. Mathematician Maria Reiche followed up on Kosok's work, examining the Nazca Lines for more than 40 years to identify many geoglyphs she believed have an astronomical relationship to various celestial bodies, a research team noted in a 2021 paper. Yet after analyzing the geoglyphs, the modern-day team found that only a relatively small number had a possible alignment to a star or solar event such as a solstice.

"The results suggest that the geoglyphs, as a whole, certainly cannot be interpreted as a calendar system," the team wrote. However, this doesn't discredit the idea that the Nazca Lines had an astronomical significance, Christiane Richter, a researcher at the University of Applied Sciences in Germany and first author of the 2021 paper, told Live Science in an email.

Since the paper's publication, Richter and her team's research has indicated that around 8% of the geoglyphs have some form of lunar alignment. It is "highly probable that celestial bodies played a role in the creation of the drawings," Richter said in an email.

Offerings such as ceramics, crabs, corn and earrings made from Spondylus shells (a genus of bivalves known as thorny oysters) were also placed on low rock platforms near some of the geoglyphs, especially those shaped like trapezoids, Lambers noted in his paper. Spondylus shells are normally found farther north, in Ecuador, but during El Niño events, they can appear farther south, in Peru. These shells, alongside crabs and corn, tend to be associated with water and fertility, Lambers noted.

Another idea is that the geoglyphs themselves may have been used for ritual processions. Some of the geoglyphs are made with a single, uninterrupted line," Nieves said. "Those are the ones that would lend themselves for processions since people could walk them in a single file."

Some of the activities at the Nazca Lines may have helped foster a sense of community and equality, said Darryl Wilkinson, a professor of religion at Dartmouth University who has written about the geoglyphs. For instance, "walking the lines was a group activity, and participating in such processions would have likely created a feeling of community among those involved," Wilkinson told Live Science in an email. "I interpret the Nasca lines as geared towards the realization of a relatively more equal expression of community."

Whatever the reasons for their construction the Nazca Lines are awe inspiring today. Lambers wrote in his essay that the Nazca people who built them "succeeded in transforming one of the driest deserts in the world, over the course of many centuries, to serve the region’s inhabitants as an expression of their cultural ideas and a setting for their social activities."

Actor Christina Applegate was diagnosed with multiple sclerosis (MS) over five years ago — but this week, she announced that a recent reevaluation found that she doesn't have the condition after all. In the wake of that revelation, she's been left without a diagnosis, and she said on a podcast that she felt she was "back at square one, where I don't know what's going on with me."

Applegate's case is not totally unique, although MS diagnosis has improved over the years. Studies offer different estimates of how frequently MS is misdiagnosed, with rates ranging from 5% to over 40%, depending on the patient population and clinical setting. There is also some degree of underdiagnosis — cases in which people with MS aren't flagged as having the disease.

So, how difficult is MS to identify, and what does that mean for patients? Live Science spoke with experts about the current state of MS diagnostics and the improvements that may be coming in the future.

"It's also really important that doctors and patients be aware that it's not inappropriate to revisit a diagnosis — to make sure it's right," Dr. Ari Green, chief of the Division of Neuroimmunology and Glial Biology at the University of California, San Francisco, told Live Science.

The importance of early diagnosis

MS is an autoimmune disorder in which the immune system attacks the central nervous system, meaning the brain and spinal cord. These attacks harm neurons directly and also take aim at myelin — a fatty, insulating substance that coats neurons' outgoing wires and helps them send signals efficiently.

This damage leads to distinctive scarring in nerve tissue and causes a range of symptoms, including vision problems, muscle weakness, tingling sensations, dizziness and bladder control issues. Patients with untreated and advanced MS can lose the ability to walk and stand or, in some cases, develop partial or complete paralysis.

These severe outcomes are becoming rarer as treatments have improved significantly, Green said. Current treatments keep immune attacks at bay and thus prevent further nerve damage.

"It's moved from people ending up with severe, profound disability at 10 or 20 years of disease, and now it's at like 30 or 40 years of disease, they have modest disability," Green told Live Science. The disease most often emerges between age 20 and 40, although it can occur in any age group. Importantly, Green said, "the earlier people initiate treatment who have MS, the better they do over the long term."

For that reason, it's important to reach an MS diagnosis efficiently, so that patients can start that critical treatment, said Dr. Yohance Allette, a neuroimmunologist and researcher at Penn State Health. "You're trying to be as proactive as possible with this."

"A diagnosis of exclusion"

However, there is no single, surefire test that can reliably show that a person has MS. "With MS, it comes down to the keyword 'criteria," Allette said.

MS experts have compiled a list of criteria, which are updated periodically, that reflect how the features of MS show up in lab tests; brain, optic nerve and spinal cord scans; and patients' symptoms. (Green was among the dozens of experts involved in the latest update, which was conducted in 2024 and published in 2025.)

So, what does diagnosis look like for a patient today? The first step is to recognize symptoms that might point to MS.

Those early symptoms — such as issues with balance, vision or bowel control — vary significantly from person to person and may not immediately raise red flags that the patient has a neurological problem, Green said. The way those symptoms emerge can be a clue, though; typically, MS symptoms worsen over the course of a day or a few days and then dissipate, he noted.

Once concerning symptoms are flagged, MRIs of the brain and spinal cord are taken. The scans may reveal evidence of myelin damage, and neurologists note the shape, size and location of those lesions. Damage often appears near blood vessels, since that's where immune cells access the brain, Green noted.

Other conditions — like migraine, uncontrolled diabetes or vascular disease — can also come with some myelin damage, so it's key to look for specific patterns related to MS. Neurologists who specialize in MS are practiced at this task, while doctors in other neurological specialties may not know how to distinguish MS-related myelin damage from that caused by other conditions, Allette and Green both noted.

MRIs of the optic nerves can also show MS-related damage, and these scans are emphasized in the latest diagnostic criteria, Allette noted. Electrophysiologic tests, which assess the function of nerves, are also "super important because they tell you something totally different than just seeing a lesion on MRI," Green said. Further signs of MS can be found via spinal taps, which sample the fluid around the brain and spinal cord that may carry proteins and inflammatory cells related to MS.

In addition to collecting these clues, doctors must rule out diseases that look similar to MS. These include neuromyelitis optica and myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD) — two other autoimmune conditions that affect the central nervous system. Both these diseases are associated with distinctive, rogue immune proteins, called autoantibodies, that latch onto various parts of the nervous system; those specific antibodies are not seen in MS.

Other conditions — such as the inflammatory disease lupus and neuromuscular disease myasthenia gravis — can sometimes look like MS at first glance, as well. Some of these "MS mimics" can be ruled out with data from spinal taps or antibody tests, while others require a more laborious battery of assessments.

"Ultimately, it's a diagnosis of exclusion," Allette said. "There are things that you can rule out quickly," while others take time to investigate thoroughly.

Conditions like MOGAD and neurosarcoidosis, an inflammatory condition sometimes mistaken for MS, can actually be worsened by MS medications, Green noted. So if a patient's MS flare-ups worsen after they start a treatment, that could hint that something else is the culprit, he said. But because there may be long gaps between flare-ups, doctors may need to track a patient for some time before their worsening becomes apparent.

Gaps to fill?

Given all the tools available, a patient can be reasonably confident in their MS diagnosis, Green said.

"In general, there's a fair amount of diagnostic confidence that comes with MS diagnosis today," he said. However, that confidence is highest when the tools are in the hands of a specialist who is following the most up-to-date criteria, he noted. The test results require interpretation, and that's one place where uncertainty can creep in.

Regarding Applegate's circumstances, "to speak bluntly, I think the case came as a bit of a shock because we always expect that part of society to have quick access [to high-quality medical care]," Allette said. For some patients, the road to accessing specialty MS care can be long, which can result in missteps, and even misdiagnoses, along the way. Applegate went five years with an incorrect diagnosis, but "would that have been seven or eight years for somebody who doesn't have that access?" Allette speculated.

Without knowing the details of Applegate's case, Allette and Green said it would be difficult to speculate on what resulted in her misdiagnosis. (Applegate mentioned that her brain scans had been reassessed with a "new technology," but didn't go into specifics.)

Looking toward the future of MS diagnostics, Green and Allette think emerging proteomic tests hold a lot of promise. Such tests generate a profile of the proteins and smaller fragments, called peptides, in a patient's blood or cerebrospinal fluid. They can be designed to look for proteins involved in driving the underlying immune attacks, as well as signs of nerve damage that MS wrecks, they explained.

These in-depth, protein analyses could help paint a more comprehensive picture of MS, which could ultimately help scientists "look at that whole system in concert" to reach a strong diagnosis, Allette said.

No proteomics-based diagnostic tests for MS have been approved yet, Green clarified. And even with those upcoming advances, Green doubts there will ever be a simple, one-time test that can determine a patient has MS. "I think that's probably unlikely, that it would ever be that straightforward," he said.

He does think that, in time, scientists could pare down the number of tests required to reach a diagnosis, but he argued that the clinical evaluation conducted by a neurologist will likely remain crucial. "I'm doubtful that there's going to be a test that will fully replace that," he said, "at least in the foreseeable future."

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

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Last week, Tesla unveiled a new "flying" edition of its Roadster electric vehicle. While some experts remain skeptical that the new "Rocket" EV is feasible in the real world, the demonstration reignited a long-standing debate about whether flying cars could soon become a reality.

In response to this demonstration, Live Science polled its readers on whether they think flying cars will be available to consumers in the next five years.

Over 280 readers responded, with the largest voting group, 34% of readers, picking "No, we need more than five years for flying cars to take off." The next-highest voting bloc was even more skeptical with 23% of readers choosing "No, flying cars will never happen."

Several comments reflected this pessimistic view, with one commenter leaving this response: "No flying cars. In my almost 60 years of driving experience I find that most people can't handle driving in 2 dimensions let alone 3. Besides that we have face [sic] so many other problems: hunger, poverty, inadequate healthcare, the careless disregard for our planet. What are we leaving my grandchildren and great grandchildren??"

Other commenters echoed this sentiment. "It will never happen as some cheap alternative to electric or petrol driven vehicles," one person responded. "Gravity is master on this planet so to rise above that and be floating or propelled around on some sort of air current, Nah! I cannot imagine the damage that will take place in any livable area, towns, suburbs, cities, parks, etc, etc., that list is endless. And imagine the protests should a general public be allowed to dive and fly above any or all livable areas."

Not everyone was as adverse, with another commenter remarking on how far Tesla's technological development has come. "The flying roadster is a statement of what Mr. Musk can do with technology more than anything else. In the same way he can make the Roadster fly, be sure that the technology designed into the Tesla Y, the Cybercab or the Starship are at the very frontier of science. Mr Musk has singlehanded revolutionized the car industry and space travel in less than 20 years (the first Tesla car was sold in 2008). No small feat."

Do you agree or disagree with our readers? Tell us your thoughts in the comments.

With artificial intelligence (AI), scientists have a powerful new tool for creating never-before-seen proteins, which can be used to make either groundbreaking new medicines or devastating bioweapons.

To help guard against nefarious uses of these proteins, scientists have recently figured out a way to "watermark" them without compromising their function. A team from Google DeepMind developed this technique to better track the provenance of AI-designed proteins.

"This has the potential to reduce biosecurity threats, such as unauthorized toxin creation, and may help with database curation, preventing artificial designs from cluttering the standard databases," said Roy Sleator, a biology professor at Munster Technological University in Ireland, who was not involved in the research.

"In practice, it could help trace a design's origin, flag engineered proteins for extra biosecurity checks, and reduce misleading claims about how a protein was made," Sleator told Live Science in an email.

However, in its current form, the same AI technologies that add watermarks can also strip them away, other experts warned.

New ways to hide watermarks

The unveiling of the AI program AlphaFold in 2020 was a milestone in protein engineering. The tool, which won Demis Hassabis, John Jumper and David Baker the Nobel Prize in Chemistry in 2024, can reveal the 3D structure of a protein from the sequence of its building blocks, called amino acids. Proteins fold like origami, adopting 3D shapes that dictate their function.

However, AlphaFold's technology also opened the door to generating brand-new proteins that could be used to create biothreats, including viral proteins that can evade our immune systems and existing vaccines.

"Anything that can be used for good can be used for bad," said George Rose, professor emeritus of biophysics at Johns Hopkins University.

Current screening tools identify novel dangerous or restricted molecules by seeing how similar their amino acid sequences are to those of recognized threats. But the problem is that AI could come up with proteins that don't look like anything we've ever seen. That's what the new watermarking technique aims to solve.

The DeepMind team has framed the watermarking effort as a "family" of related techniques they call SynthIDBio. The first member of this family is SynthIDBio-sequence, which encodes watermarks into the amino acid sequences of proteins created by a program called ProteinMPNN.

When users tell ProteinMPNN the desired 3D shape for their protein, it chooses amino acid options that ultimately fold into that shape. SynthIDBio-sequence subtly influences how the program chooses each amino acid according to a secret watermarking "key." Once the sequence is generated, anyone who knows the hidden code can assess how likely the sequence is to have been created under the key's bias. In their recent study, the DeepMind team showed that proteins built with this watermark could still bind to their targets as well as non-watermarked proteins.

A sister technique, called SynthIDBio-structure, instead embeds a watermark directly into the protein's structure. It does this by altering the function of AlphaFold 3, DeepMind's flagship protein prediction algorithm.

When AlphaFold predicts a structure, SynthIDBio-structure gives it a side mission: The AI must make minuscule tweaks to how the atoms in the protein are arranged. These tweaks can be picked up by a detector later, and they're small enough that they don't look like obvious distortion.

In a test, these two systems created hidden watermarks that could be detected with incredible accuracy, flagging more than 99% of watermarked proteins and correctly ignoring 99.9% of non-watermarked proteins.

How to bypass a protein watermark

Live Science spoke to several experts who agreed that SynthIDBio was an impressive technical feat. However, they said it wasn't ready for widespread implementation yet.

The two techniques are "effective but brittle," Bruce Wittmann, a principal applied scientist at Microsoft, told Live Science in an email. That's because, as the DeepMind team also notes in their paper, the watermarks can be easily removed.

"For sequences, watermarks can be removed by 'resequencing' — effectively, altering the protein amino acid sequence such that the watermark is no longer detectable," Wittmann said. "For structures, watermarks can be removed by adding noise to or otherwise modifying the spatial coordinates of the structure." Screening tools wouldn't be able to detect if a watermark had been removed from a protein.

Experts are also skeptical that watermarking would provide a long-term solution for biosecurity.

An indelible watermark could identify who originally made a nefarious protein, or identify when a user was accessing a protein generation software without permission. This might deter some criminals, but terrorists looking to create a novel protein for a biological weapon would be less likely to care about being identified after a successful attack, said Max Brackmann, a chemical, biological, radiological, and nuclear arms expert at the Spiez Laboratory in Switzerland.

Additionally, the vast majority of software for protein prediction and generation is open-source, meaning much of the code is freely available to use and modify. That makes it far harder to bake watermarking into these programs. Wittmann warned that the field would have to shift toward closed-source models before watermarks could become an industry standard.

He added that watermarking could act as one layer of a biosecurity defense shield, rather than offering standalone protection. Top-down regulation would be challenging to enforce. "I imagine it would be very difficult to ensure the regulations were being followed," he said.

Rose was even blunter about regulating the use of generative proteins.

"I'm convinced it won't work," he said. "Once there's a sweet technology that does something, government regulation to keep it under wraps has never been really successful."

Help us improve Live Science Pro: We're always trying to make our content better. Leave us feedback about Pro here.

TENERIFE, Spain — The commander of NASA's Artemis II mission briefly feared that he and his crew would never return home from their trip around the moon after overshooting their turn-back point.

Commander Reid Wiseman and his three crewmates were supposed to reach 219,667 nautical miles (252,788 standard miles, or 406,823 kilometers) — farther than any humans have ever traveled from their home planet — before turning back toward Earth on the sixth day of their 10-day mission to the moon.

But the odometer on the Integrity spacecraft continued to tick upward as they shot past their intended point of return, leading the astronaut to fear that something had gone terribly wrong, he told an audience here at the Starmus VIII festival earlier this week. (This semi-annual event is held to celebrate achievements in science, exploration, and creativity.)

"Mission control in Houston had told us our maximum distance would be 219,667 nautical miles and that was the furthest we were supposed to be from Earth," Wiseman said. "I was watching this number, and I saw it hit 219,667, and I thought, 'Great, this is the farthest we will be from Earth, and the next number I will see will be 219,666 ‪—‬ we'll be going home.' But about three minutes later, I didn't see 219,666; I saw 219,668. It went up. I was like. 'Huh? That's weird.'

"And then about three minutes later, it goes to 219,669, and that was the moment that I felt real fear because I thought we had just gone too far ‪—‬ we're never going to come home ‪—‬ and so I was very scared," he added.

Then, at last, he saw the counter start to drop. Meanwhile, NASA astronauts Victor Glover and Christina Koch were at the window, doing science observations of the moon, and Canadian Space Agency astronaut Jeremy Hansen was sending reports back to mission control ‪—‬ so Wiseman's moment of terror went unnoticed.

When Wiseman saw the odometer click back to 219,668 nautical miles, he said, "We're going home," and the crew let out a cheer. "I knew there was a good chance we might make it," he added.

In an interview with Live Science's sister publication The Week Junior Science+Nature, Wiseman paid tribute to NASA's Earth-based teams for the ultimate success of the mission.

"Getting home safely is a testament to the engineering rigor and the flight control teams back here on planet Earth, who put this rocket together and then who controlled it as we went out to the moon and came back. Those are the true heroes of this mission. They have real courage."

The Artemis II mission launched from NASA's Kennedy Space Center in Florida on April 1. It was the first crewed flight of the Orion space capsule and the first crewed mission to travel to the moon since Apollo 17 in 1972, taking nearly 10 days to fly around the lunar far side and return to Earth.

Nearly every moment of the crew's activities in the Orion capsule was livestreamed to the world, garnering massive public interest in the mission. The Artemis II crewmembers were awarded the Stephen Hawking Medal for Science Communication at the Starmus VIII festival.

Are you a NASA nerd? See how well you score on our Artemis quiz to find out!

Crows are intelligent animals that can use tools, hold grudges and even host funerals. Now, new research suggests these birds can make certain decisions faster than humans and monkeys — another potential sign of their smarts, the researchers argue.

In a study published Thursday (Oct. 22) in the journal Science, researchers found that two carrion crows (Corvus corone) could distinguish the direction of moving dots on a screen in an average of 235 milliseconds, or less than a quarter of a second. By contrast, historical studies of humans suggest they make decisions in similar tasks six seconds as fast.

The birds were highly accurate, and recordings of their brain activity suggested that their decision-making process resembled that seen in primates and humans.

Given birds and mammals have evolved along separate paths for more than 310 million years, "this suggests that evolution may have independently developed similar solutions to the same computational problem," study co-author Andreas Nieder, a professor of animal physiology and director of the Institute of Neurobiology at the University of Tübingen in Germany, told Live Science in an email.

Inside a crow's split-second decision

To understand how crows make decisions using cues in their environments, the researchers trained two carrion crows to complete a visual task on a touchscreen. The birds watched a cloud of white dots moving against a black background. Some dots moved to the left or right while others moved randomly. The crows had to determine the predominant direction of the dots' movement and peck the corresponding target on the screen to earn a mealworm reward.

By changing the proportion of dots moving together, the researchers could make the decision easier or harder for the crow. When most dots moved in the same direction, the answer was fairly obvious for the birds. But when only a small percentage moved together, the birds had weaker visual evidence to base their decisions on.

The crows reached nearly 100% accuracy when many dots were involved and the motion was clear. But even when just 3% of the dots moved in concert, both birds performed significantly better than just guessing, getting the answer right 50% of the time.

The birds maintained high accuracy in different rounds of the experiment, suggesting they were not sacrificing judgement for quickness.

The study did not directly compare crows to humans and monkeys performing the exact same task. However, previous studies suggest that humans and monkeys take roughly twice as long on comparable, self-paced visual motion tasks.

What happens inside the crow brain?

To understand how the birds reached their decisions so quickly, the researchers recorded activity from 248 neurons in the nidopallium caudolaterale (NCL) — a region of the bird brain that's considered functionally comparable to the prefrontal cortex in humans and primates. Birds lack the layered cerebral cortex found in mammalian brains, but the NCL performs similarly advanced functions.

In primates, neurons accumulate sensory information and their activity increases until it hits a critical threshold and the brain reaches a decision. The new findings suggest that crows use a comparable process, the researchers concluded.

"The bigger implication is that a brain does not need a mammalian neocortex to perform sophisticated computations," Nieder said.

The team could use neural activity to predict the crows' eventual choice "as early as 70 milliseconds after" the dots appeared, Nieder said. That was roughly 170 milliseconds before the crows' behavioral responses, meaning their pecks at the screen.

The speediness of the crows' decision-making may reflect the demands of the birds' daily lives.

"Flight places enormous demands on visual processing and sensorimotor [sensation and movement] coordination," Nieder said. "Birds must navigate three-dimensional environments, avoid obstacles, and react quickly to moving objects. Finding food and capturing prey can also require rapid, precise decisions. These pressures may have favoured fast information processing."

But for now, scientists don't know why crows seem to outpace primates in this particular type of decision-making. The study included only two birds and no direct comparisons to primates, so more work could be done to confirm the results and explore that question further.

For Nieder, observing the faster decision-making process in crows raises a broader question about how scientists define intelligence.

"Rather than assuming that the mammalian brain is the blueprint for intelligent behaviour," he said, "we can study different species to discover which computational principles are shared across animals and which reflect adaptations to their particular environments."

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

Picture a number line, with the values running from the smallest to the largest. New research shows that the human brain uses a similar system when comparing numbers; in the study, scientists uncovered a "mental map" in which numbers have unique coordinates in the brain, which may help us place them in order of magnitude.

"Numbers are abstract concepts, but our brains have ways of organizing them that allow us to compare and reason about their values," said study co-authors Daniela Valério, a postdoctoral researcher in the INSERM-CEA Cognitive Neuroimaging Unit (UNICOG) in France, and Stanislas Dehaene, the director of UNICOG.

"What is fascinating is that the brain can bring together numbers that look very different, such as integers [whole numbers] and fractions, within a common system," they told Live Science in a joint statement.

That system is a map for both sets of numerical values within the brain, they reported Thursday (Oct. 22) in the journal PLOS Biology.

To investigate how the brain represents different types of numbers, Valério, Dehaene and their colleagues used a high-resolution functional magnetic resonance imaging (fMRI) scanner, which tracks blood flow through the brain as an indirect measure of activity. They measured brain activity in 20 adults while they worked through a simple task of comparing numbers — a mix of fractions and whole numbers — and determining whether each number was bigger or smaller than the previous one shown.

The brain scans revealed distinct activity patterns in the anterior inferior parietal cortex — part of the brain that's known to be key for processing numbers. As participants compared numerical values, the brain region lit up in an organized pattern resembling a number line. The whole numbers and fractions were represented along this shared line according to their size, rather than being mapped in separate systems.

The brain's shared map brings different number formats into a common system based on the quantities they represent, the researchers concluded.

"For me, it is how the brain gets from a symbol to its meaning," said Abiot Derbie, a cognitive neuroscientist and founder of the company LifeByLogic, which makes psychology assessments.

The fraction "¼" contains the digit "4," but the fraction's value is much closer to zero, he noted. "The activity patterns reflected that numerical relationship, going beyond the digits themselves," Derbie, who was not involved in the research, told Live Science in an email.

The idea that the brain represents numerical magnitude in the parietal lobe is not novel. However, scientists mostly understood how the brain dealt with whole numbers, while its strategy for fractions was not well understood. The new work builds on that existing research by exploring how both numerical magnitude and number type are processed together.

"To the best of our knowledge, this is the first study to investigate the geometry of neural representations in a task involving both integers and fractions," the researchers wrote in their report. "In the future, it might be interesting to expand the present work to decimal numbers."

From previous work, "scientists already knew that fractions and whole numbers engage overlapping parts of the brain's number-processing network," Derbie said. "This study gives us a clearer picture of how their values are organized."

In the future, the team could examine how this neural representation varies across people of different ages, educational levels and mathematical backgrounds, Derbie suggested. The study also included only native French speakers, so may not reflect differences across language or culture.

"I would want to see how this organization develops as people learn," Derbie said. For instance, the team could follow children before and after they learn about fractions, to see whether changes in brain activity accompany better understanding.

In the current study, the participants found it more difficult to compare fractions than to compare whole numbers, the researchers noted; they were slower and made more errors while working with fractions, which was expected. But the study's results don't offer hints as to why.

"Our study was not designed to explain why fractions are harder to learn or understand," Valério and Dehaene told Live Science. "What is new in our study is that we show that these different types of numbers are organized within a shared map in the brain."

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

Cryptic snakes in Southeast Asia have evolved a remarkable trick for evading predators: Instead of slithering, they arch their long bodies and tumble away at high speeds.

The dwarf reed snakes (Pseudorabdion) pull off this acrobatic feat by keeping their head in a relatively fixed position while rotating the rest of their body, according to a new study published Monday (Oct. 19) in the journal Current Biology.

Researchers filmed the snakes from different angles to better understand the mechanics of the rolling, or cartwheeling, behavior. They found that the snakes were capable of reaching velocities of up to 12.1 feet per second (3.69 meters per second), which is much faster than they can slither (technically referred to as undulating locomotion).

"Rolling allows them to escape from danger very quickly," study first author Yosuke Kojima, a lecturer in the biology department at Toho University in Japan, told Live Science. "In our study, their peak forward velocity during rolling was, on average, four times that of normal undulating locomotion."

Dwarf reed snakes are secretive, often nocturnal species that live across Southeast Asia, where they are prey for birds and other snakes. Although the snakes are extremely cryptic and usually hidden beneath leaves or other natural objects, people occasionally observe the serpents' dazzling rolls.

In a 2023 study, researchers formally documented the rolling behavior for the first time in one dwarf reed snake species (P. longiceps), which researchers observed in northwestern Malaysia in 2019. Kojima's team started independently observing the behavior around the same time in the Malaysian state of Sarawak, on Borneo.

"I had never seen anything like it before, and I immediately wanted to learn more about it," Kojima said.

For the new study, researchers filmed the rolling behavior multiple times in three dwarf reed species ‪—‬ P. saravacense, P. collaris and P. longiceps — between 2019 and 2022. The team also studied three reed snakes from another genus (Calamaria), which didn't perform the behavior.

Kojima said their study builds on the 2023 research by quantifying the rolling movements, confirming the overall movement pattern that research described, and revealing further details, including how the snakes stabilize their heads.

Snakes aren't the only tumblers in nature. For example, some desert spiders can roll away from danger, as can mother-of-pearl moth caterpillars (Pleurotya ruralis or Patania ruralis). However, the snakes are unique in that they seem to have good control over their rolls.

Rolling movements typically destabilize the head and disrupt sensory-guided adjustment, especially at high speeds, according to the authors of the new study. In other words, it's hard for animals to control their bodies when they're rolling around. The snakes' technique of keeping their heads relatively fixed and often elevated off the ground likely counters what would otherwise be destabilizing effects.

In addition to studying speed and form, the researchers found that the snakes could move in a relatively straight line, readily moving along a "racetrack" that was only 8 inches (20 centimeters) wide. The researchers noted that the snakes often ended their tumbling routine by diving underneath nearby objects, so they seem to remain aware of their surroundings.

The rolling is a behavioral innovation that allows the snakes to overcome their physical constraints and pull off an otherwise impossible movement, according to the researchers.

"Behavioral innovation can give rise to surprising new abilities that we would not expect from an animal's appearance alone," Kojima said.

Researchers have speculated that the bizarre behavior could surprise and confuse predators, in addition to being a rapid means of escape. The authors of the 2023 study also hypothesized that rolling would result in a patchy scent trail, and because king cobras (Ophiophagus) use scent cues to locate their prey, this could make it harder for the predators to hunt dwarf reed snakes.

How much do you know about snakes? Test your knowledge with our snake quiz!

On Monday (Oct. 19), Japan's space agency launched a first-of-its-kind sample-return mission to Mars. The historic endeavor marks another major step toward humanity's shared goal of understanding — and perhaps eventually colonizing — one of our closest planetary neighbors, experts say.

The Japan Aerospace Exploration Agency's (JAXA) Martian Moons Exploration (MMX) probe is an international effort, constructed with help from NASA, the European Space Agency (ESA) and others. Over the next few years, it will closely study the Red Planet's twin moons, Phobos and Deimos. The spacecraft will snap close-up photos of the pair before attempting to land on the larger satellite, Phobos, to scoop up rocky material that will hopefully be carried back to Earth in around five years.

If the mission is successful, the returned samples will finally settle a decades-old mystery about the origins of both moons. The findings could also help paint a picture of Mars' ancient history and provide clues about what the early solar system was like.

"This mission marks a transformative leap in our capacity to investigate the Martian system," Sonia Fornasier, an astronomer at the Paris Observatory who has studied Phobos and Deimos extensively and is a project scientist for MMX's infrared spectrometer instrument (MIRS), told Live Science. It "ranks very high" among the missions we have sent to the Red Planet so far, she added.

What will MMX do?

JAXA launched the MMX probe on board an H3 rocket, which lifted off from Tanegashima Space Center in Kagoshima prefecture at 3:41 p.m. EDT Monday (4:41 a.m. Tuesday local time), Live Science's sister site Space.com reported. (The mission was initially scheduled to launch in 2024, but it was delayed due to initial concerns about the H3 rocket.)

The camper-van-sized spacecraft successfully separated from the rocket's fairing just over an hour later, and on Wednesday (Oct. 21), JAXA announced that the mission had passed the "initial critical operations phase," meaning the probe is now locked into its roughly 140 million-mile-long (225 million kilometers) journey to Mars, which will take around 10 months.

"MMX took its first step today," Naoki Murakami, general manager of Mitsubishi Electric’s space division, which led the design of the MMX probe, said in a postlaunch news conference early Tuesday morning (Oct. 20), according to The Japan Times. "This marks the beginning of a long, five-year journey."

Once the probe arrives at the Red Planet in August 2027, it will insert itself into a "quasi-satellite orbit" around Phobos. In other words, MMX will circle Mars alongside the moon but will not be gravitationally bound to it, similar to around half a dozen "quasi-moons" that currently accompany Earth around the sun.

After collecting data from a distance for a few months, MMX will swoop down and attempt to land on the surface of Phobos ‪—‬ not once, but twice.

During the first landing, MMX will hover just above the moon and deploy a mini rover, dubbed Idefix, onto the moon's surface. The wandering robot, built by the French and German space agencies, will have to contend with extremely weak gravity as it trundles across the surface of Phobos: The rover weighs around 55 pounds (25 kilograms) on Earth but will weigh only around half an ounce (15 grams) on Phobos, according to ESA.

Once Idefix has completed its initial assessment of the moon's surface, the entire MMX probe will set down on Phobos, on top of the spacecraft's four-legged lander module. Mission scientists hope this goes a lot more smoothly than the attempted landings of Japan's "Moon Sniper" and Resilience lunar landers, which crash-landed on Earth's moon in 2024 and 2025, respectively.

Two of the MMX lander's legs contain built-in sampling devices ‪—‬ one that will drill into Phobos and another that will hoover up surface material. The second device, dubbed the Pneumatic Sampler (or P-Sampler), was built by the Blue Origin-owned private company Honeybee Robotics on behalf of NASA and will collect its material in a "matter of seconds," Kris Zacny, vice president of the Exploration Technology Group at Honeybee Robotics, said at an Oct. 15 NASA news conference. "You blink, and it's all done."

In total, JAXA aims to collect around a third of an ounce (10 grams) of material from Phobos. That would be around twice as much material as the space agency managed to snag on its most recent sample-return mission, Hayabusa2, which collected samples from the "spinning-top" asteroid Ryugu in 2019, finding materials rich in surprising organic compounds.

Once the samples have been acquired, at some point between late 2028 and early 2029, the probe will conduct a series of close flybys of Mars' smaller moon, Deimos, before beginning the long trip back to Earth in late 2030 — the first return flight ever attempted by a spacecraft sent to Mars.

When the probe returns to Earth in 2031, it will release its samples in a 20-inch-wide (60 centimeters) container that will fall back to our planet's surface, most likely somewhere in Australia, according to ESA.

What could we learn about Phobos and Deimos?

Mars' twin satellites, which were first spotted by American astronomer Asaph Hall in 1877, are nothing like Earth's constant companion. For starters, they are much smaller; Phobos is around 14 miles (22 km) across, while Deimos is just 7.5 miles (12 km) wide. The duo also have lopsided shapes and are between 12 and 64 times closer to Mars than the moon is to Earth. (Phobos, meaning "fear," and Deimos, meaning "terror," are named after the sons of the Greek war god Ares, the counterpart to the Roman war god Mars.)

Phobos is dominated by the 6-mile-wide (10 km) Stickney crater, which was left by an ancient asteroid impact. The larger moon is also slowly falling toward Mars and may eventually be ripped apart before it reaches the Red Planet's surface.

Other Martian spacecraft, such as the Emirates Mars Mission orbiter, have flown close to the moons, and NASA's Mars rovers have frequently looked up to see the satellites eclipsing the sun in Mars' sky (sometimes both at the same time). Yet many mysteries remain about the pair.

"Mars is right in our cosmic backyard, and yet we haven't explored the planet's moons," Nancy Chabot, a space exploration expert at the Johns Hopkins Applied Physics Laboratory in Maryland and the deputy principal investigator of NASA's MEGANE instrument on board MMX, told Live Science in an email. "MMX will do this!"

The biggest mystery surrounding Phobos and Deimos is their origin. Some researchers suspect the satellites are asteroids, or maybe even comets, that have been captured by Mars' gravity, while others think the moons emerged from the debris of an ancient impact on the planet's surface, similar to how Earth's moon formed.

Neither theory is conclusive, meaning the moons' origins "remain enigmatic," Christopher Edwards, a planetary scientist at Northern Arizona University and one of NASA's participating scientists for MMX, told Live Science.

For example, explaining how Mars captured the moons is "quite hard from an orbital mechanics perspective," but if they did form from a debris disk from an ancient impact, they should have coalesced into better-defined spheres, Edwards said.

"MMX will solve this debate thanks to the spacecraft observations and the detailed analysis of the samples of Phobos on Earth," Fornasier said. The data the probe collects from its flybys of Deimos will also allow researchers to generate a "full characterization of this body," she added.

Fornasier is "particularly excited" by the possibility that the moons are captured asteroids because that would mean they would likely contain "organic and hydrated materials," which would have a big "astrobiological implication" and would shed light on what the early solar system was like.

What could we learn about Mars itself?

Regardless of how the twin moons formed, researchers also stand to learn a lot about Mars and how planets form and evolve.

"Phobos and Deimos are interesting, but not just in their own right," Tom Statler, an MMX program executive and scientist in NASA's Planetary Science Division, said at the Oct. 15 news conference. "Their presence is a key piece of the larger story of the Mars system. By uncovering the moons' origin, we'll gain new insights into the history of both Mars and Earth."

If the moons did form via an impact scenario, the samples MMX collects may also contain actual pieces of Mars for researchers to study.

"If these objects are in fact pieces from the Martian surface that have coalesced moons, we'll collect the best-preserved samples of the Martian surface," Edwards said. Other fragments of Mars have already reached Earth as meteorites. However, entry into Earth's atmosphere can transform them.

If Phobos is a chunk of Mars, that would be a real boon to NASA, which canceled its Mars Sample Return program — a mission that would have retrieved samples collected by the Perseverance rover — earlier this year. The agency's researchers will receive up to 15% of the MMX samples to analyze.

During its three-year stay in the Red Planet's system, the Japanese probe will also collect lots of data on Mars that could contribute to a wide range of future findings. "MMX will conduct in-depth studies of the Martian atmosphere, with a particular emphasis on dust and water transport mechanisms and the escape processes shaping Mars' atmospheric dynamics," Fornasier said.

This atmospheric data could temporarily fill a gap left by the recent death of NASA's iconic MAVEN spacecraft, which stopped sending data back to Earth late last year.

Analysis of craters on the Martian moons could also provide clues about other events in Mars' history. For example, some researchers think the Red Planet may have once had rings like Saturn or a larger moon.

Other experts are hopeful that the MMX findings could help lay the groundwork for future missions to explore ‪—‬ and perhaps colonize ‪—‬ Mars. "The samples from MMX will bring forth paradigm-shifting science on the Mars system for generations to come, especially as NASA prepares to send the first humans to Mars," Nicky Fox, associate administrator for NASA's Science Mission Directorate, said in a recent statement.

The next sample-return trip to Mars will be China's Tianwen-3 mission, which is scheduled to launch in 2028 and will aim to land on and retrieve samples directly from the Red Planet's surface, according to Space.com.

About 251 million years ago, volcanic eruptions wiped out most life on Earth. For about a million years, the Siberian Traps in Russia spewed huge clouds of carbon dioxide into the atmosphere, leading to the most severe extinction event in our planet's history.

Equatorial temperatures spiked, making much of the land too hot for life. Meanwhile, the oceans became acidic and most of the creatures in them suffocated from lack of oxygen. Known as the Permian-Triassic mass extinction or the "Great Dying," it ultimately destroyed more than 90% of ocean life and 70% of terrestrial species.

However, in a corner of what is now China, a refuge of pollen-producing plants avoided that fate and created an oasis for surviving animals. Research suggests that this was not the only place where plants were able to weather catastrophic climate change during the Great Dying, and that plants may have been better able to withstand the extinction event than other organisms.

"Plants do indeed sometimes have a lot of resilience because they can't move individually, and even as a population, they're not very good at moving," Chris Thomas, an ecologist and evolutionary biologist at the University of York in the U.K., told Live Science. As a result, many plants have evolved mechanisms to survive in place despite difficult conditions, he said.

As climate change raises global temperatures and throws ecosystems into upheaval, plants will need to draw once more upon this resilience. Many plant species have evolved unique adaptations that help them weather harsh conditions. Experts told Live Science that these adaptations — along with a hefty dose of luck — will now decide the difference between survival and extinction.

Growing with the flow

Unlike most animals, many plants have the ability to regenerate limbs — and those limbs can make them better able to adapt to new environment conditions. Plants in general have higher developmental plasticity than animals, which means that they have greater flexibility to change how their cells and tissues grow and develop.

"Many plants have what we call indeterminate growth and modular body plans," Amy Angert, a botanist at the University of British Columbia in Canada, told Live Science. Indeterminate growth means that an organism continues to grow and develop indefinitely throughout its lifespan.

"If we lost an arm, it would be gone forever. But on plants, if you cut off a branch, they can sprout new ones and those new ones can then receive signals from the current environment instead of being stuck with sort of developmental programs from the past environment."

For example, researchers found that resprouts on holm oak trees (Quercus ilex) are better able to cope with drought than those that had not resprouted.

And because buds can go dormant, many plant species can resprout after catastrophic events, such as fire. Cape Floristic Region in South Africa, for example, is the smallest of the world's six recognized floral kingdoms, and most of its plant species depend on fire — its plants resprout after fire and many of their seeds require fire to germinate.

Some plants, such as the Snow Gum (​​Eucalyptus pauciflora), have a thick layer of insulating bark to protect their buds, while others like stinging nettles (Urtica dioica) bury them underground in a "bud bank". The soil insulates the seed's buds from extreme heat and cold and protects most of the plant from life-threatening conditions. This widespread adaptation allows herbaceous plants to endure through the winter and plants with bulbs to hide their tissues from the ravages of fire.

Storing seeds for better times

Plants can also store seeds underground when times are difficult. Almost 350,000 plant species produce seeds. For most of these species, the seeds contain dormant tiny versions of the young plant, with all the structures that will turn into leaves and roots.

"Seeds can live essentially in stasis in the soil," Daniel Anstett, an evolutionary ecologist at Cornell University, told Live Science. "You can have the seed bank where certain seeds might come back, and there's access to the backward library of genetic information that many plants can ultimately draw upon."

Seed banks are a vital tool for resilience in many plant species. They create the opportunity for metabolically inactive individuals to reanimate when environmental conditions improve, according to a 2021 paper published in the journal Nature Communications. "When lucky, at least some of these individuals will awaken in the future when the environment is more conducive for growth and reproduction," the authors wrote.

Rapid evolution

Seedbanks can also be reservoirs of genetic diversity, which is integral to being able to adapt to new environments.

"The raw material for adaptation comes from genetic variation," said Angert. "Genetic variation is larger in large populations, and genetic variation can be shared between populations as the environment changes — if individuals can disperse successfully between them."

In a paper published in journal Science earlier this year, researchers, including Angert and Anstett, showed rapid evolution saved scarlet monkey flower (Erythranthe cardinalis) populations from prolonged drought in the U.S. and Mexico between 2010 and 2018.

"They can either grow really fast, flower and put out seeds before the fall drought takes effect, or they can grow much more slowly and bunker down,” Anstett explained.

The researchers sequenced the genomes of 55 scarlet monkeyflower populations to find areas within their genomes linked to coping with stress and drought. They tracked the populations and how they changed over the period. Some populations experienced rapid evolution to cope with the changing environment.

They found that, based on populations’ genetic diversity, they could predict whether a population would be able to survive the drought — even before it started.

While this is only one plant species, Anstett believes it could be true of other organisms too.

Flexible photosynthesis

Some plants are able to transform how they produce energy to endure a changing environment. This is what Zhen Xu, a paleobotanist at the University of Leeds in the U.K, thinks allowed some plant species to survive the Permian-Triassic mass extinction and might become increasingly important for plants in today's changing climate.

Plants use photosynthesis to convert carbon dioxide and water into sugars and oxygen, and use stomata, or small pores on their leaf surface, to regulate the amount of carbon dioxide entering the plant.

Many plants open their stomata during the day to let in CO₂ and release oxygen. Others use CAM photosynthesis, which stands for "Crassulacean acid metabolism," to close their stomata during the day and protect themselves from the heat. At night, they absorb CO₂ and transform it into an acid, which they store in their tissues to be used to make sugars during the day.

"CAM photosynthesis is very common in present day desert plants, like the cactus and succulents," Xu told Live Science. "It's a very smart way to escape from the high temperature or aridity during the daytime."

In a study published in journal Nature Ecology & Evolution earlier this year, Xu and colleagues showed that plants that used CAM photosynthesis had an advantage during the Permian-Triassic mass extinction.

They found that Lycophytes, or are ancient vascular plants, switched to CAM photosynthesis around the time of the mass extinction. "We think CAM photosynthesis may be the special strategy to survive" and allowed these plants to dominate after the mass extinction, Xu said.

Hopeful monsters

Some plants go to even more extreme lengths. During cataclysmic events, plants have turned into "hopeful monsters" to survive environmental upheaval, past research shows.

In nine separate events over the past 150 million years, many flowering plants duplicated their whole genome to give themselves a better chance of survival, according to research published in journal Cell earlier this year. The duplicate genome gives them more opportunities to evolve and adapt to challenging environmental conditions.

"We see clusterings of whole genome duplications in time, and every time it corresponds with a described, important geological event, whether it's a global cooling period, whether it's a global warming period, or whether there's an extinction event," study co-author Yves Van de Peer, a genome biologist at Ghent University in Belgium, told Live Science at the time.

Boils down to luck

Still, the survival of specific plant populations or species often boils down to luck, experts told Live Science.

Plants "essentially have this broad toolkit" but "some of the plants have some pathways, and other plants have others, and some have some traits, and some have others", Anstett said. Whether the particular tools they have will help depends on the conditions they face.

During the Triassic-Permian mass extinction, the plants in refugia in China (and elsewhere) were in the right place at the right time, with the right suite of potential adaptations at their disposal and enough genetic variety to tap into them.

The same holds true for modern-day species facing a changing climate and potential extinction. Angert said there are ways to make plant species "luckier" in the years ahead, such as connecting fragmented populations to increase genetic diversity, which increases the suite of potential tools at a plant species' disposal.

"The best thing we could do is to leave larger and better connected populations on the landscape," she said.

Anstett agreed. "If populations become really disconnected, then potentially we're eroding away whatever toolkit that these plants have to be able to adapt."

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Climate change is making Earth progressively rounder, new research finds.

The findings are a signal of human-caused climate change, however, and tracking the shape of the Earth can help reveal just how much impact people are having on its ice caps.

Our planet is not a perfect sphere. Because of its rotation, it is a bit flatter at the poles and bulges in the middle. But the new study reveals that Earth is getting rounder at an accelerated rate, largely due to shifts caused by the melting polar ice caps.

This finding applies only to the solid parts of the planet; the ocean continues to bulge outward at the equator.

The study, published Sept. 9 in the journal JGR Solid Earth, used direct measurements from the global navigation satellite system (GNSS) to track the planet's shape-shifting over time. This system provides direct measurements, but there are limits in how it can be used. For example, there are few GNSS stations near the North and South poles and few in remote oceans because they must be deployed on buoys.

Christoforos Kotsakis, a professor of geodesy at the Aristotle University of Thessaloniki in Greece, developed a new method for analyzing GNSS data to better capture the changes in the planet's surface. He found that the poles are rising and the equator's bulge has been shrinking, each by about 0.04 inch (1 millimeter) per year between 2011 to 2015. That's a small number, considering Earth's diameter at the equator is about 7,926 miles (12,756 kilometers). But that change is bigger than between 1997-2000, when Earth was becoming about 0.02 inch (0.5 mm) rounder per year. This means Earth's shape is rounding at 0.016 inch (0.4 mm) more per year with each decade that passes.

The shift is being driven by polar ice melt, which takes pressure off the Earth's crust and allows it to rise slowly, similar to how rising bread dough springs back after you press a finger into it, Kotsakis reported. Meanwhile, increased mass toward the equator puts pressure on the crust there, reducing its bulge. However, there's a catch: When considering the solid Earth and the ocean together, the planet is getting flatter by about 0.03 inches (0.8 mm) a year because the ocean is getting bulgier at the equator as water shifts away from the poles. This 'water weight' overwhelms the rounding happening in the rock below.

These shifts are also slowing Earth's rotation, other research has shown.

Researchers also track Earth's changing shape using measurements of its gravity field, which varies depending on the mass of particular regions. GNSS changes and gravity field measurements don't match up perfectly, Kotsakis found, which indicates that the planet's shape and gravity field aren't in perfect lockstep. However, the two methods can be used together to track the major effects of climate change, especially the melting of Greenland and Antarctica and the varying movements of ocean water.

Western states that were thought to be resistant to prolonged drought may be more vulnerable than scientists previously believed, a new analysis of groundwater reserves in the Colorado River Basin finds.

Researchers revealed the four states that together make up the Upper Basin — Colorado, New Mexico, Utah and Wyoming — lost almost twice as much groundwater as the Lower Basin did during an intense drought in the southwestern U.S. between 2020 and 2022. The finding was unexpected and might signal a turning point for the region, because the Upper Basin has long been seen as more resilient to dry spells than the Lower Basin, said Esther Oyedele, a doctoral student in geosciences at Virginia Tech and the study's first author.

"The Upper Colorado River Basin has historically been considered more resilient because it receives more precipitation, particularly snowfall in the Rocky Mountains," Oyedele told Live Science in an email. "I think the important takeaway is that we should not assume that the Upper Basin will remain relatively resilient simply because it has historically received more precipitation and snowmelt."

The Lower Basin comprises parts of Nevada, California and Arizona. Less rain and snowfall means the Lower Basin naturally has less groundwater recharge, or less replenishment from other water sources, than the Upper Basin. On top of that, the Lower Basin generally has higher evaporation rates and substantial water demands, given that roughly 30 million of the 40 million people that depend on the Colorado River for water live in the Lower Basin, Oyedele said.

In the new study, published Oct. 13 in the journal Water Resources Research, researchers used satellite and hydrological data to estimate groundwater depletion across the Colorado River Basin between 2004 and 2023. The data included measurements of surface water, soil moisture and snow-water storage, as well as observations from the Gravity Recovery and Climate Experiment mission and its successor, called the Follow-On.

The results showed that groundwater depletion has been a persistent problem in the Colorado River Basin over the past two decades, but losses accelerated in 2019. The three-year drought that began in 2020 is the principal cause of this, because it shrank the snowpack in the Rocky Mountains, increased evaporation and boosted water demand across the basin, Oyedele said.

During the drought between 2020 and 2022, the Upper Basin lost around 4.2 cubic miles (17.5 cubic kilometers) of groundwater, while the Lower Basin lost about 2.3 cubic miles (9.4 cubic km). In total, the Colorado River Basin lost 14 cubic miles (58.3 cubic km) of groundwater ‪—‬ equivalent to 25 million Olympic-size swimming pools' worth of water ‪—‬ during the study period, between 2004 and 2023.

It's unclear why the deficit is so much higher in the Upper Basin than in the Lower Basin, but the Upper Basin's proximity to and dependence on the mountains for aquifer recharge probably didn't help, Oyedele said. As snow melts, some of it replenishes groundwater, so a reduction in snowfall between 2020 and 2022 would have affected the Upper Basin particularly badly, she noted.

The Upper Basin also recorded more aquifer recharge during wet periods before the drought than the Lower Basin did, so it's possible that the pronounced decline during the drought was linked to a higher initial amount of groundwater in the Upper Basin, Oyedele said.

Next, the researchers used advanced statistical methods to explore the relationship between groundwater and surface water in the Colorado River Basin. Due to global warming and the overallocation of the Colorado River's water in a 1922 document, the river's flow is now 35% less than it was on average in the 20th century. Water scarcity in the basin has reached alarming levels, according to the study, and Lake Mead and Lake Powell, the two largest reservoirs in the U.S., dropped to record lows in August.

The team found that in the Upper Basin, groundwater levels evolve in the same direction as surface water, but with a slight delay. This suggests groundwater losses occur due to a lack of recharge and more aquifer pumping during periods of drought, when surface water levels drop. In the Lower Basin, however, this link is weaker and more complex. The results showed that groundwater losses sometimes preceded surface water declines during the study period, suggesting that groundwater depletion is not simply tied to less surface water trickling into the ground or to humans extracting groundwater when there's less surface water available. Instead, groundwater is consistently being overused, Oyedele said.

"This distinction is important because it suggests that groundwater depletion is not simply a direct response to surface-water shortages," she said. "Human water use, particularly sustained groundwater extraction, may also play a significant role."

Looking ahead, it's hard to tell if the Upper Basin will continue to lose more groundwater than the Lower Basin and what that would mean for the region, Oyedele said. What seems clear, however, is that the Upper Basin is more vulnerable to drought than experts had thought.

"Continued warming, changes in snowpack, prolonged drought, and increasing water demand could place additional pressure on groundwater resources across both basins," Oyedele said. However, future groundwater responses will depend on several factors, including precipitation, snowmelt, water use and management decisions, she added.

On the management side, Oyedele suggested tackling groundwater and surface water together rather than as two separate resources. Groundwater helps to sustain river flows, and rivers can recharge aquifers ‪—‬ so the two are interconnected. Groundwater often serves as a backup during drought, but it shouldn't be treated as an unlimited reserve, she said.

The Milky Way's supermassive black hole is surrounded by a surprising trove of heavy metals, according to new observations by the James Webb Space Telescope (JWST). The metals may offer new clues about how Earth got its share of heavy elements — but it could also make one of the greatest mysteries about our local black hole even harder to solve.

In astronomy, metals refer to any element heavier than hydrogen or helium, with common examples including oxygen, carbon, iron or gold. These elements are forged through nuclear fusion in the hearts of stars that are reaching the ends of their lives, before being sprayed into space and incorporated into new generations of stars.

Scientists say the material spotted by JWST likely came from supernovas ‪—‬ stellar explosions that blasted the metal into the region around Sagittarius A (Sgr A*), the monster black hole in the middle of our galaxy.

The metals, detected as gas, appear to have the same composition as several nearby stars, which suggests both the stars and the gas originated at the same time. Researchers shared the observations in a paper published Oct. 19 in The Astronomical Journal, following up on work published in The Astrophysical Journal in May.

"We know there's a black hole at the centre of our galaxy pulling material into itself, but we see that it's eating a lot less material than other supermassive black holes, and more slowly," Nicole Ford, first author of the new paper and a doctoral student in astrophysics at McGill University in Montreal, said in a statement. "Part of understanding why this is happening means looking at the properties of the materials available for it to consume, including gas, dust and the stars orbiting around it."

JWST orbits at Lagrange point 2, which is about 1 million miles (1.5 million kilometers) from Earth in the opposite direction of the sun. The telescope identified the heat signatures of specific gas clouds billowing near the black hole, as well as the metal content within those clouds.

"These findings could advance understanding of how metals are distributed around supermassive black holes in more distant galaxies, as well as the processes that supplied Earth with many of these elements," McGill researchers said in the statement. The metals' presence "influences how quickly gases cool, which in turn influences how readily the gas can be drawn into a black hole," they added.

The previous study in The Astrophysical Journal showed that gas emissions near the black hole have been influenced by conditions in the local clouds. Unfortunately, this means the gas alone cannot serve as a proxy for how often the black hole has been active, the researchers said.

See how much you know about black holes with our black hole quiz!

A rare silver coin minted during the reign of a famous Viking king has been discovered in a massive hoard in Norway that now comprises 5,500 coins and counting.

The coin is inscribed with the name of the Norwegian king Olaf Haraldsson, who ruled from 1015 to 1028 and, as St. Olaf or "Olaf the Holy," is considered the national saint of Norway.

Fewer than 20 coins minted during Olaf's reign have ever been discovered, and the newfound coin is a "national treasure," according to a statement from the University of Oslo's Museum of Cultural History.

"Here we have a coin bearing the king's portrait and a cross, with another cross on the reverse," University of Oslo coin expert Svein Gullbekk said in the statement. "It is a Christianisation coin on a grand scale."

Olaf is credited with establishing Christianity in Norway — an early step toward its full conversion about a generation later.

"We can see how King Olaf used coinage to legitimise the new faith and to establish himself as a Christian king of European standing," Gullbekk said. "This is branding."

Viking king

Haraldsson learned about Christianity when he joined Viking raids against England and France as a young man, and he was baptized in the French city of Rouen in about 1013, according to the statement.

He became Norway's king in 1015, and in about 1024 proclaimed that only Christianity would be legal, according to the University of Bergen. Much of Norway, however, remained faithful to the Norse gods during his rule, especially around the central Trøndelag region and in the eastern parts of the country.

But Olaf was made a Christian saint shortly after his death in 1030. He is now recognized as one of the first Christian kings of Norway and the first Norwegian king to issue coins in his own name.

The newfound coin is part of the Mørstad Hoard, which was discovered near the village of Rena in April. At that time, the buried hoard was described as the largest ever found in Norway and was estimated to contain almost 3,000 silver coins. However, subsequent research has determined that it includes anywhere from 5,500 to more than 6,000 coins, the statement said.

Mistaken identity

Anne Skogsfjord, a museum researcher charged with cataloging the coins, thought the Olaf coin was an Anglo-Saxon penny at first. But then she read the inscription and realized it was minted in Norway under Olaf.

"I could see that it read ONLAF R+ NORMANORV. … Could this really be a coin of Olaf Haraldsson that I was holding?" Skogsfjord said in the statement. "And it was! It was a very special moment."

The coin was struck between about 1024 and 1028, near the end of the Viking Age, and circulated for 20 to 25 years before someone deposited it in the hoard, the statement said.

Although the minting of the coin was a political and religious act, the coin also seems to have been used as currency; both sides bear numerous small cut marks, which was a common way of determining whether a coin was made completely of silver.

Gullbekk said Haraldsson himself had decided what the coins would look like and may have been present when they were minted.

"It is entirely possible that this very coin from Mørstad was once held in the king's own hand," he said in the statement.

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

The Nazis were far from completing a working reactor for their atomic bomb program, despite claims by the project's leader that it was almost ready, a new study finds.

The German physicist Werner Heisenberg wrote in 1947 that the reactor for the "Nazi bomb" project ‪— which culminated in Germany's B8 nuclear reactor ‪— was almost finished at the end of World War II.

Heisenberg, who led the reactor's development, claimed the reactor was "just insufficient" to create a self-sustaining fission reaction and that it lacked only a "relatively small amount of uranium" to work.

If it had worked, the B8 reactor would have confirmed that a fission chain reaction was possible, marking a key step toward the German development of an atomic bomb. It could have also spurred the development of specialized fission reactors used to create weapons-grade plutonium from uranium. Instead, the atomic bomb was developed first by the United States and was used to force the surrender of Japan in August 1945. (Germany had already surrendered in May 1945.)

The new study, published Sept. 29 in the journal PNAS Nexus, used historical documents and forensic investigations of two of the project's surviving uranium cubes to refute Heisenberg's claim. The new research indicates that the German B8 reactor had less than half the amount of "heavy water" and about half the amount of uranium it would have needed for a continuous chain reaction.

"My results argue that Heisenberg was off by roughly a factor of two," said first author Patrick Park, a doctoral student at Princeton University who co-wrote the study while at Columbia University.

Park said Heisenberg's mistake was understandable: His calculations were only approximate, and the project was relocated to a rock cellar in the town of Haigerloch, Germany, after Berlin was bombed.

"People were dying or starving and so these reactor calculations were not his first priority," while many details of neutron physics were unknown at that time, Park told Live Science in an email. "Given these circumstances, I think he did the best he could."

Heavy water

To answer the question of how far the reactor for the Nazi bomb project got, the scientists began by tracing archival records of hundreds of uranium cubes that had been used by German scientists. The B8 reactor consisted of five concentric circles of uranium cubes suspended on chains within the heavy water tank. The German scientists planned to place a radium-beryllium neutron source into the reactor's core to kick-start the chain reaction with a flood of neutrons that would split the uranium nuclei and release more neutrons, furthering the chain reaction.

Heavy water is a form of water that contains the neutron-heavy hydrogen isotope deuterium. Like the mainly-graphite blocks and rods used in many reactors, it can be used to "moderate" or slow down fast neutrons created in a fission reaction so they trigger fission — and more neutrons — in nearby uranium atoms. The Germans also used small amounts of graphite in their reactor, but as a coating to reflect neutrons back into the chamber.

By combining the records of the cubes, heavy water and graphite used by the German scientists with measurements of the two surviving cubes, the study authors created a mathematical model of the reactor that agreed closely with historical measurements. This enabled them to establish that the heavy water reactor was far from achieving a stable reaction. The findings also helped them examine the suggestion that the Germans should have instead built a graphite-based reactor like the nuclear pile developed at the University of Chicago to build the American bomb.

But the study authors determined that a graphite-moderated reactor was unfeasible in wartime Germany because the local supply of coal available to create graphite contained high levels of neutron-absorbing boron, making it useless.

Instead, the heavy water used in the B8 reactor was produced at a single factory in Norway, which was occupied by Germany from April 1940 until May 1945. However, the reactor contained only about 370 gallons (1,400 liters) of heavy water, instead of the more than 780 gallons (roughly 3,000 liters) it would have needed, the researchers determined.

Heavy water makes up a tiny fraction of a percent of ordinary water, and extracting it by electrolysis in the Norwegian factory took extraordinary effort. The factory was producing as much heavy water as it could, but the B8 reactor would have needed more than twice the amount it produced during the entire war, the researchers wrote.

Another finding is that the B8 reactor had about half the amount of uranium it would have needed to sustain a fission chain reaction. The reactor contained a total of 664 cubes, each weighing about 5.11 pounds (2.32 kilograms), for a total of 3,390 pounds (1,540 kilograms) of uranium. Similar cubes were distributed among other experimental groups, giving a total inventory in wartime Germany of about 1,100 cubes of uranium.

But the researchers determined that the B8 reactor would have needed at least 1,200 cubes to work. Germany, therefore, was not about to develop a reactor for an atomic bomb in 1945. Contrary to Heisenberg's claims, the heavy-water reactor was not nearly ready, and a working graphite reactor was impossible.

"We conclude Germany could not have built heavy water nor graphite reactors during World War II," the researchers wrote.

Mark Walker, a historian at Union College in Schenectady, New York, who wasn't involved in the study, said the findings explain Germany's decision to develop a heavy-water reactor, since a graphite reactor was not feasible and they didn't know at the time how much heavy water would be needed.

Walker is the author of "Hitler's Atomic Bomb: History, Legend, and the Twin Legacies of Auschwitz and Hiroshima" (Cambridge University Press, 2024) and a noted expert on Germany's wartime nuclear efforts. He agreed that Germany could not have made a graphite reactor during World War II.

"This paper argues that if the Germans had done something they did not do, then this would have failed," he told Live Science in an email. "While this is counterfactual history, it is an interesting engineering analysis."

Sailor Matt Rutherford has dreamed for several years of becoming the first person to circumnavigate the Arctic Ocean solo, nonstop and unassisted. He finally set out from western Greenland on June 25 to achieve this goal, but threatening encounters with Russia's security agency less than two months later forced him to reverse course.

Rutherford is the founder and executive director of the nonprofit environmental organization Ocean Research Project, which gathers and analyzes marine data from a sailboat. His route took him around the southern tip of Greenland, through the Denmark Strait and into the Greenland Sea. From there, he sailed through the Norwegian and Barents seas, and reached Russia's Novaya Zemlya archipelago in mid-August.

He was planning to continue to Canada and end his journey where it started, but Russian officials halted him in his tracks and ordered him to turn around.

On his way home, Rutherford told Live Science about his adventures and why he wants to complete this loop. In an interview on Sept. 23, he also revealed what he'll do differently on his next attempt to avoid another Russian interception.

Sascha Pare: Where are you currently, and what are the conditions like?

Matt Rutherford: I'm about halfway between Greenland and Newfoundland in the Labrador Sea. The conditions aren't too bad; I mean, it's close to a gale, but it's not quite a gale. [Editor's note: A gale is defined as an area of sustained surface winds of 34 to 47 knots (39 to 54 miles per hour).] It's just a little hard to do anything. I've got dishes in the sink that are all wedged in there that I really need to deal with ‪—‬ but I don't feel like it, because you're just getting tossed around. Waves are crashing on the cockpit. Normally, I do video calls under a dodger [a canvas screen on a boat or ship that provides protection from spray], and you can see the ocean in the background… But I'm going to get hit by a wave if I do that.

SP: You're sailing home to Maryland after a rather perilous expedition. How long have you been at sea for?

MR: I left in mid-May, and I've been basically underway for the most part since then. At this time, currently, I've only been at sea for a few days, because I left Greenland a few days ago. The longest stretch I was continuously at sea this year is 59 days, although I was planning on doing longer than that, so that sucked. Essentially, I was attempting to do a nonstop, single-handed circumnavigation of the Arctic. That's where this all sort of came out of. I tried in 2018, but you couldn't get the Russian permits. And the Russians were the problem in the end [this year]. I got defeated by Russian bureaucracy, essentially. And there was some weird stuff going on with the ice up there this year. [Editor's note: Sections of the High Arctic were impassable due to a relatively cold summer and solid ice fields.]

SP: What happened with the Russians that forced you to turn back?

MR: The FSB got me. [Editor's note: The Federal Security Service (FSB) is Russia's main security agency and a successor to the Soviet Union's KGB.] They boarded me twice, actually. I've never been boarded in the ocean in my life, and I've been sailing 20 years, all over the place. I got about 1,000 miles [1,600 kilometers] into Russia, roughly. I got into the Northern Sea Route. If you just draw a line due north, I was due north of West China — it was way over there, about halfway around the world in the Arctic. I made it about halfway, because I started in Aasiaat, Greenland.

They boarded me once, and then they turned me around and boarded me again. It's a bit of a strange situation, I guess. Two days after I turned around, the ice that I was waiting to open opened, and I sent them an email — the NSRA, the Northern Sea Route Association in Moscow — and said, "Hey, it's open. Can I pretty please go?" And they just got mad at me, like, "You'll be in violation of your permit; you have to turn around."

SP: You're planning to try the circumnavigation again next year. Will you do anything differently to make sure you complete it?

MR: The boat's pretty good to go ‪—‬ which is great, because that's a huge time sink. Ideally, hopefully, if I can get north of [the Norwegian archipelago] Svalbard again like I did this year, then I'm going to stay north of [the Russian archipelago] Franz Josef Land, and I'm going to basically ride the polar ice cap all the way from Svalbard to the Northwest Passage — all the way to Alaska and beyond, essentially.

Because I've learned how the FSB operate, and I know where they're keeping their ships now. Even though I was north of Novaya Zemlya, they still were able to get me. But if I'm over there, north of Frank Josef, they don't go that far, so they won't be able to get me up there. I've figured out a couple of other things that I'm not even going to say, honestly ‪—‬ there are workarounds to get them to [leave me alone]. I'm going to go a little bit quiet.

The NSRA gives you the permit to do this, but the FSB are the people who patrol it. And the FSB don't like the NSRA. I learned that when they boarded me, because they think that they're the ones who should control the Northern Sea Route, not the NSRA. So there's [a] beef between them; they don't talk. There's a lack of communication, which benefits me. I can lean heavy onto the NSRA side, because they don't have boats; they're not going to board you. And they're the ones you have to check in with every 24 hours in Moscow; you've got to send them an email every 24 hours. So I'll do all of that stuff with those guys, but I think there's some ways I can avoid the FSB even knowing where I am, essentially, while still complying with my permit in the NSRA.

Basically, I've got to do the Northern Sea Route without getting within 12 miles [19 km] of any Russian land, period ‪—‬ even a little island, even a rock that sticks out that's 10 feet by 10 feet [3 by 3 m]. That's going to be real tricky, because there are a lot of little islands down there. But the FSB is mostly on the European side; they have almost no boats over on the east side or the middle. So if you can get past the European side by hugging the coast way the hell north, hopefully I can get past where they patrol, and then I can just shoot on through.

Nobody else in the world does this ‪—‬ nobody else in the Arctic, nobody else anywhere. There's literally no other body of water on Earth where you've got to get permits, and then you've got to get boarded like this. It's only Russia, and only north of Russia. And that's because there's a huge amount of natural gas, they think, buried above Russia. So Russia's trying to claim everything to the North Pole.

Technically, it's international waters, so the U.N. is like, "No, this is not right." And Russia's like, "Whatcha gonna do about it?" It's kind of hard to argue with that ‪—‬ and it's north of Russia, so nobody else is there. They've got free rein, and they've got all the icebreakers and whatever else.

Everything else is about the same. I need to secure my hot sauce better, because every time I open my cabinet, they fall out all over the place. There's little things like that ‪—‬ quality-of-life things. I'll probably bring some more heated socks — electric socks and electric gloves. I'll try to make better videos — but I'm not a content creator, and I don't want to be an influencer.

SP: Can you tell me a bit about your background and what led you to this point?

MR: I did this whole circumnavigation of the Americas — nonstop, single-handed — back in 2011 where I spent 309 days alone at sea on this little 27-foot (8 meters) boat. When I got back from that big, crazy trip — which I made a documentary about ["Red Dot on the Ocean: The Matt Rutherford Story"] — I created a nonprofit called Ocean Research Project, where, basically, we use sailboats to do research. We focused mostly in 2013 and 2014 on garbage-patch-related microplastics. In 2013, we mapped out the eastern side of the Atlantic garbage patch, because nobody had got to the eastern side of it. I think it was 160,000 pieces per square kilometer, or something like that. And then, we did some stuff in 2014 in the Pacific garbage patch with the University of Tokyo; we did a joint paper with them.

But mostly what we focus on is Arctic research. Since 2015, we've been heading up to Greenland — sometimes the Northwest Passage also, but primarily Greenland — doing research related to glaciers, for the most part. An ocean-terminating glacier sort of has a river of melted water underneath it, and it creates upwelling, and the upwelling has nutrients. So it mixes nutrients with the ocean and creates this perfect recipe for growth for phytoplankton and zooplankton. And then, we look at the different stages of decay between an ocean-terminating glacier, a land-retreated glacier or a deglaciated fjord. In the middle phase, when a glacier starts retreating back on land, it just creates a river of muddy water, essentially; it turns the fjord into a mud puddle. You can't have photosynthesis if you're in a mud puddle.

SP: Have you been collecting samples or data on this expedition?

MR: Well, it's a little tricky on a boat under these circumstances. I took 50 samples, which were just water samples, and those were from Newfoundland to Aasiaat, Greenland. Nicole [Nicole Trenholm, Ocean Research Project's science director] has a NASA internship out at JPL [Jet Propulsion Laboratory]. She was publishing a paper looking at their model that they have [ECCO-Darwin], and I've kind of forced my way into the paper — well, the organization did, with Nicole's help — by adding these samples. Now we have in situ data, physical data, that we can compare to the model data. That was the only thing we did this year. It's a couple-thousand-mile stretch with 50 water samples in it, so it's a pretty straightforward sort of thing.

Nicole is trying to publish multiple peer-reviewed scientific papers from our previous data. She's got a traffic jam of data, so she needed some time to finish publishing papers from stuff we've collected over the last few years. There is no money anyways. I could still grab some samples on the way up there [Greenland]. And it's trying to promote the nonprofit through it, because people will pay a lot more attention to this stuff than they pay to traditional research expeditions.

SP: What are your hopes for the Ocean Research Project once you tick off this goal?

MR: Basically, we're trying to expand the organization over the next couple of years. I'd like to bring in another one or two more scientists, because we're up there for three months in Greenland, and sometimes we go to the Northwest Passage — and it's a lot for one scientist.

The big problem we're having is that when Elon Musk was part of DOGE [U.S. Department of Government Efficiency], they cut a massive amount of polar funding — something like 88% of it — because apparently climate change is a hoax and they hate it and you're not allowed to research it either, right?

Basically, nobody's got money. We don't typically get NSF [National Science Foundation] funding; we get more foundation funding, because it's hard to get NSF funding, even before all this stuff. Now that the funding has been cut on the governmental level, a lot more scientists are going after the foundation grants that we used to have a lot less competition for. That makes it a little tricky, too, because now they're getting a flood of requests that they didn't usually get in the past.

This interview has been condensed and edited lightly for clarity.

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Astronomers have discovered the lightest known pair of neutron stars — two ultradense stellar remnants that circle each other every 2 hours, 22 minutes, veering toward an inevitable collision about 82 million years from now. By timing radio pulses from one of the stars, the researchers detected three subtle effects predicted by Albert Einstein's general theory of relativity and found that the theory describes the pair's motion to within about 1% — proving the visionary physicist right yet again.

The researchers published their findings Sept. 15 in the journal Physical Review Letters.

Neutron stars are the collapsed cores of massive stars that exploded as supernovas. Each packs more mass than the sun into a ball roughly 12 miles (20 kilometers) in diameter. Some, called pulsars, spin rapidly and sweep beams of radio waves across the sky like cosmic lighthouses. Their rotation is so steady that their pulses work as extraordinarily precise clocks.

Very few pulsars orbit another neutron star. "There are only 30 such double neutron star systems, and the relativistic effects are very strong if they are in compact orbits," study co-author JinLin Han, an astronomer at the National Astronomical Observatories of the Chinese Academy of Sciences, told Live Science via email.

The first such pair, discovered in 1974 and known as the Hulse-Taylor binary, provided the first evidence for gravitational waves — ripples in space-time predicted by Einstein. Such waves carry energy away from an orbiting pair, so its orbit should gradually shrink, and the Hulse-Taylor orbit shrank at just the rate Einstein's theory predicted.

Later, the "double pulsar," which completes an orbit every 2.45 hours, matched the predicted rate to within about 0.01%. Eventually, this shrinking forces such pairs to merge, unleashing gravitational waves like those the Laser Interferometer Gravitational-Wave Observatory and Virgo interferometer picked up in 2017.

A newly discovered pair

The new system, designated PSR J1856-0039, lies roughly 4,200 to 6,500 light-years from Earth. In 2020, it turned up in a survey of the Milky Way's disk by China's Five-hundred-meter Aperture Spherical Radio Telescope (FAST), the world's largest single-dish radio telescope.

"We have discovered about 900 pulsars," Han said of his team's work. "After a few follow-up observations, this one is very extraordinary."

The pulsar spins about 43 times per second, and the two stars are separated by roughly twice the distance between Earth and the moon. But the "most attractive feature" is the short orbital period of about 2.36 hours, Han said. "This is the second-shortest one, and it must show stronger relativistic effects than the famous double pulsar and the Hulse-Taylor system."

The team observed the pair with FAST 17 times between 2020 and 2025, sometimes long enough to cover a whole orbit. The researchers measured the arrival times of the system's pulses and then fit that data to orbital models that accounted for relativistic effects, like subtle changes to the pulse arrival times at different parts of the stars' orbits.

"With so many measurements by FAST, which would be hard to match in accuracy with other telescopes, we got not only the basic parameters of the pulsar and its orbit but also three relativistic effects," Han said.

First, the orbit is shrinking as the stars radiate gravitational waves, drawing them about 9 feet (2.7 meters) closer each year. Second, the oval orbit turns slowly, by 17.6 degrees per year — some 150,000 times faster than the relativistic drift of Mercury's orbit. Third, because both gravity and speed slow time, the pulsar's clock runs at a varying pace along the oval orbit, shifting its pulses by up to about half a millisecond.

"From these measurements, we determined the pulsar mass and the companion mass," Han explained. "The total mass is the lowest among all known double neutron star systems." The pulsar weighs about 1.3 times as much as the sun, and its companion is just 1.19 solar masses — one of the lowest-mass neutron stars known. Simulations suggest that supernovas can't forge neutron stars much lighter than that.

The stars will merge in about 82 million years. That merger will probably leave behind a heavier neutron star of about 2.26 solar masses, though the remnant could instead collapse into a black hole, the researchers estimate.

Another win for Einstein

Any two of the three effects are enough to calculate both stars' masses. The third then serves as an independent check, because if general relativity is correct, all three must point to the same masses — and they do.

"We found that general relativity is needed to explain the data, and the consistency is about 1%," Han said. The double pulsar test is more precise, but it drew on 16 years of data, compared with about five for the new pair. "Unfortunately, we could not beat this description of gravity," Han added, referring to physicists' hope of finding cracks in Einstein's theory that might reveal new physics.

Next, the team hopes to detect "frame dragging," an effect in which a spinning mass twists space-time around it, making nearby orbits wobble. "In the future, we will monitor this pulsar, probably over decades, to detect the frame dragging induced by the neutron star's spin," Han said.

Measuring the effect would reveal the pulsar's moment of inertia, which depends on how its mass is spread out inside. That would provide "a novel constraint" on how matter behaves at the crushing densities in neutron star cores, Han said — one of the biggest open questions in physics.

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