A fossil that sat in a museum collection for over a century is a previously unknown species of predatory dinosaur, researchers have found. The discovery could help scientists solve a longstanding mystery about how some of the Cretaceous period's most formidable hunters spread around the globe.

The dinosaur lived on what is now the Isle of Wight in southern England about 120 million years ago. It belonged to a group of two-legged carnivores called megaraptors, which are related to tyrannosaurs. But unlike tyrannousars, megaraptors are thought to have relied on their powerful arms and large curved claws to attack prey and defend themselves.

The newly identified species was described in an Oct. 14 study in the journal Royal Society Open Science. It is the first megaraptor identified in Europe, filling an important gap in the fossil record of a group whose evolutionary history remains poorly understood.

"It is a real mystery that this fossil was overlooked for so long, sitting in a drawer for nearly 100 years," study first author Cassius Morrison, a researcher in the Department of Earth Sciences at University College London (UCL) said in a statement. "Lots of bones are found on the Isle of Wight — who knows what else is waiting to be discovered."

Unconquered female warrior dinosaur

The discovery of the megaraptor began in 1924, when an amateur fossil collector discovered a dinosaur skull fragment on the Isle of Wight. The specimen eventually entered the collections of London's Natural History Museum, but it was largely forgotten.

Recently, researchers revisited the fossil as part of a study on dinosaur braincases. To identify the animal, the researchers used micro-CT scanning to examine the fossil's internal structure and build detailed 3D digital models of the space that once held the dinosaur's brain.

The researchers then compared the animal's anatomy with that of other meat-eating dinosaurs, including tyrannosaurs, spinosaurs and other theropods (the group of two-legged, mostly meat-eating dinosaurs). Several features differentiated the unknown specimen, including an almost oval opening where the spinal cord entered the skull and an unusual, hourglass-shaped ridge at the back of the braincase.

Computer-based evolutionary analyses placed the fossils within the Megaraptora family tree, supporting the idea that the skull represented a never-before-seen species. The researchers named the dinosaur Invictibellatrix amberina, combining the Latin words "unconquered" and "female warrior" for the genus name, while amberina refers to amber found in the rocks associated with the fossil.

Megaraptors lived between roughly 125 million and 66 million years ago and varied considerably in size. While early members were relatively small, some later species became enormous predators. Maip macrothorax, discovered in Argentina, may have reached up to 33 feet (10 meters) long and weighed as much as an elephant. Based on comparisons with related dinosaurs, I. amberina was much smaller, likely around 10 to 13 feet (3 to 4 m) long and standing roughly 5 feet (1.5 m) tall. The researchers estimated it weighed around 440 to 660 pounds (200 to 300 kilograms), making it one of the smallest known megaraptors.

"It was not the apex predator of its time, but for humans this dinosaur would have been more dangerous than a T. rex," Morrison said. "We would have been perfectly sized prey, about a third of their body weight. They definitely would have chased us."

Although the newly described fossil doesn't preserve the animal's arms or claws, its closest relative suggests that its claws may have measured around 4 to 8 inches (10 to 20 centimeters) long. The researchers also suggested I. amberina may have been feathered, though that feature can't be determined directly from the specimen.

A missing link in the dinosaurs' globetrotting

Scientists have long suspected that megaraptors originated in Asia before spreading to other parts of the world, eventually becoming the dominant predators across the southern supercontinent Gondwana, which included present-day Africa, South America and Antarctica. But a lack of European fossils left an important gap in verifying this migration route.

The new study's evolutionary models suggest that I. amberina descended from Asian megaraptors that dispersed into Europe around 130 million years ago. From there, members of the group may have moved through what is now Africa and further into Gondwana via temporary landbridges and temporary land connections across the shallow Tethys Ocean.

"This new species is the first proof we have that megaraptorans were also present in Europe and that they reached Gondwana this way rather than island-hopping further south," study co-author Charlie Scherer, a doctoral student at UCL Earth Sciences, said in the statement.

However, the specific route these animals took over millions of years is still unknown. The researchers also cannot yet explain why megaraptors disappeared from northern areas, but changes in climate or competition with other predatory dinosaurs may have contributed. More research on other megaraptor fossils like I. amberina could help uncover more clues.

"Work like this shows the exceptional value of working with historical museum collections where there are still many discoveries to be made," study co-author Paul Barrett, a researcher of dinosaur evolution at the Natural History Museum in London, said in the statement.

Stellar cores called white dwarfs come in an astonishing array of colors, including what scientists say is the first known green star and the reddest star ever found, new research reveals.

A white dwarf star is the dense, cooling core that remains after a low- to medium-mass star runs out of fuel. The new study, published Thursday (Oct. 15) in the journal RAS Techniques and Instruments, shows that white dwarfs come in far more colors than their name suggests.

White dwarf stars got their moniker because the first known examples glowed in either white or pale blue. The new study, however, suggests that "white" dwarfs also emit visible-light colors like pink, green, cyan, purple and yellow.

"Most stars, including most white dwarfs, behave like 'perfect radiators,' so their colour is set almost entirely by temperature. But nobody had really looked into what else might be possible for white dwarfs," Mark Hollands, an astronomer at the University of Warwick in the U.K. and first author of the study, said in a statement. "It turns out these incredibly dense stars can produce colours nobody expected, and some of them genuinely surprised me."

The variety of colors is possible due to white dwarfs' densities compared with main-sequence stars, the study suggests. Cooler white dwarfs have a density of about 1 gram per cubic centimeter, much like flowing water on Earth. The density of these white dwarfs is also millions of times denser than the sun's visible surface, or photosphere, leading to unusual conditions.

"Any trace elements that may be present, such as carbon, calcium and sodium, interact with the surrounding dense helium plasma and absorb light across a wider range of colours than they would at lower densities," the researchers said in a statement. "This shifts a star's colour away from the orange, white and blue [typical] of a perfect radiator."

White dwarfs are far away and small, making it difficult to verify their color. So, in the new study, astronomers inferred the colors using spectra, the distinctive chemical fingerprints produced by stars' light. The team analyzed the spectra within a model of color vision that the human eye can see, making the color pop out.

Scientists found that carbon-rich white dwarfs tend to be purple or pink, while those that contain debris from asteroids or comets are usually yellower. Cyan or pale-blue white dwarfs occur when hydrogen and helium molecules strike each other in very dense atmospheres.

The team also discovered WD J1330+6435 — a green star that contains rocky material. The green comes from the additional elements of calcium, lithium and sodium in the star's atmosphere, creating a unique "chartreuse green appearance" that would be visible to the human eye, if we could see it up close.

"The traces of sodium in the atmosphere of this white dwarf absorb the orange part of the spectrum, leaving behind a ghostly green glow," Hollands explained, adding that the one-of-a-kind green star "feels like something out of science fiction." The team also discovered what is likely the reddest star ever found. This white dwarf, called WD J1011+2845, is located roughly 48 light-years from our planet. It has carbon closer to its surface — because the element is being lifted from the interior, due to strong convection currents — that is bending the star's light. This process is making a "deep salmon-pink glow" because the carbon molecules are obstructing the star's other wavelengths.

Overall, in the sample of stars studied — 151 white dwarfs within 65 light-years of Earth — about 1 in 30 white dwarfs glowed in a color other than white. This could mean there are far more colorful stellar remnants littering the universe than anyone anticipated.

While working on his land in a village in northern Egypt, a man made an astonishing discovery: the remains of two massive statues of Ramesses II.

The man, Khaled el-Shahat, immediately notified the Egyptian Ministry of Tourism and Antiquities, which sent a team to the village of Behbeit El Hagar to excavate and study the statues, the ministry said in a translated statement.

Ramesses II had one of the longest reigns in Egypt's history, ruling from around 1279 to 1213 B.C. During his 66 years in power, Egypt controlled an empire that stretched as far northeast as modern-day Syria. He initiated many building projects throughout the empire, and numerous Ramesses II statues have been found throughout Egypt.

Archaeologists had previously found architectural fragments bearing the name of Ramesses II at Behbeit El Hagar, which is known for its temple dedicated to Isis, a goddess associated with healing and magic, said Mahmoud Emam, an Egyptologist at Cairo University who has worked on remains from the site but was not involved with the recent excavation. He noted that the newly found statues were unearthed on the western side of the temple complex.

"Strong Bull"

Both of the newfound statues were once larger than life, with the bigger one likely standing nearly 28 feet (8.5 meters) tall when it was originally built. However, most of what remains is its head, which is 5.2 feet (1.6 m) tall and depicts the pharaoh wearing the double crown of Upper and Lower Egypt.

Part of this large statue's back pillar has a hieroglyphic inscription that gives the pharaoh's "Horus" name: Hor-Ka-Nakht-Mery-Maat. This name means "Strong Bull, Beloved of Right, Truth," Joyce Tyldesley, a professor emeritus of Egyptology at the University of Manchester in the U.K., wrote in her book "Ramesses: Egypt's Greatest Pharaoh" (Penguin Books, 2001). In Egypt, it was common for pharaohs to have several alternate names with a Horus name, given in honor of the sky god Horus.

The second statue, which stands about 7.9 feet (2.4 m), also likely depicts Ramesses II, the statement said. The king is shown wearing the "Nemes" headdress, a type of striped headcloth that pharaohs wore, the Egypt Exploration Society notes on its website.

Near this statue is a block of pink granite with two hieroglyphic inscriptions that name Ramesses II and describe him as "King of Upper and Lower Egypt" and the "Son of Ra," an ancient Egyptian sun god, the statement said.

Previous Ramesses II finds

The new finds add more evidence that Ramesses II was heavily invested in the site.

Previous discoveries include two architectural fragments bearing the name of Ramesses II near the Isis temple at Behbeit El Hagar, Emam and his colleagues reported in a 2017 paper. One is believed to be from the upper part of a statue, and another seems to originate from the upper part of a wall.

"We concluded that Ramesses II had undertaken major building works at the temple and recommended further archaeological investigations to shed more light on the early history of the site," Emam said. He noted that the site is threatened by urban growth and that excavation work should be carried out at the temple.

Live Science reached out to the team but did not hear back by the time of publication.

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

The year is 2050, and as the sun sets, the night's first constellations emerge in perfect rows. But these amber-glowing arrays aren't stars at all; they're satellite clusters, harvesting the day's last rays before beaming their power back to Earth.

If it reads like science fiction, that's because it started that way. Called space-based solar power (SBSP), the concept featured prominently in the techno-utopian imaginations of 20th-century visionaries and writers. But for decades, it was dismissed — a pie in the sky proposal.

Now, as a new space race heats up, governments and private companies in China, the U.S., the U.K. and Japan are developing several projects to reassess the idea's feasibility. These include China's ZhuRi ("Chase the Sun") program, Japan's OHISAMA project, the U.K.'s Space Solar, and power-beaming experiments by Caltech and the Air Force Research Laboratory in the U.S., all of which are targeting test launches in the next five years.

Proponents say the technology has the potential to meet Earth's energy needs many times over while causing minimal harm to the environment. But first it needs to get off the ground: In the eyes of critics, space-based solar power is exorbitantly expensive, riddled with untested assumptions, and far too complex to be deployed in time for an urgent green-energy transition.

The challenges include getting the massive solar-panel-covered satellites into space; assembling them; getting those solar panels to constantly face our star; and then finding ways to convert, concentrate and transmit their collected power back to Earth.

Despite these hurdles, researchers keep returning to the idea. Perhaps because the most crucial step — generating energy in the first place — is already being done by the sun. Every second, our star fuses hydrogen atoms to expel the same energy as nine trillion atomic bombs. All that's left to do is catch it.

"We're not a competitor to fusion. We are fusion," Peter Garretson, the U.S. Air Force's former chief of future technology and an SBSP expert, told Live Science.

From science fiction to NASA proposal

The first glimmers of SBSP as a concept came from the Russian rocket scientist and astronautics pioneer Konstantin Tsiolkovsky, who, in 1923, suggested deploying space-based mirrors that could concentrate sunlight to Earth with enough intensity to boil 10 cups of coffee.

Tsiolkovsky's fanciful proposal soon entered science fiction, appearing in the British writer Olaf Stapledon's 1937 novel "Star Maker" as a "gauze of light traps" that an advanced alien civilization used to focus "the escaping solar energy for intelligent use" — an idea later formalized by theoretical physicist Freeman Dyson as a Dyson sphere.

Then, in 1941, Isaac Asimov made the clearest, most famous early sketch of SBSP in his short story "Reason," in which a robot colony toils aboard a power station that collects solar energy and fires it back to Earth in the form of microwaves. Asimov provided few details on the fictional station's engineering, instead focusing on the robots' religious worship of the vessel.

But the transformation from science fiction to a concrete proposal didn't take long. In 1968, aerospace engineer Peter Glaser, a consultant and project manager for the Apollo 11 mission's distance-measuring laser reflectors, drew up an engineering design for a "solar power satellite" consisting of three key elements: a ray-collecting device, a converter and a transmitter.

Glaser's collector was a disk of photovoltaic panels that would be lifted some 22,400 miles (36,000 kilometers) off the ground. Locked in a geostationary orbit above Earth and bathed in near-constant sunlight, the satellite would harvest solar rays before converting them into microwaves to be beamed, largely unimpeded through the atmosphere, to receiving antennae on the ground. Once there, the microwaves would be converted into electricity and distributed across the grid.

NASA awarded Glaser a contract to study the concept further, with both domestic and international energy crises (such as the 1973 oil crisis and the 1979 Three-Mile Island nuclear accident) adding wind to his solar sails.

But Glaser's design hit technical and financial roadblocks, the most forbidding being the project's sheer size. By 1981, when the U.S. Department of Energy's four-year study of space-based solar power was released, it estimated that a "meaningful" contribution of 300 gigawatts (sufficient to power hundreds of millions of homes) would require 60 satellites, each spanning 21 square miles (55 square kilometers) and weighing 50,000 tons (45,000 metric tons). The plan was deemed unaffordable.

Later reassessments, such as a 1997 report by NASA physicist John Mankins, pointed to advances such as improved solar cells that made the concept more realistic. Yet the overall consensus remained hostile. A 2015 report released by the Strategic Studies Institute (SSI) of the U.S. Army War College stated that while SBSP systems are "technically feasible," there was "no compelling evidence that such systems will be economically competitive" with terrestrial power systems. It concluded that "the reality is that such systems always seem to be seen as just 10 years away by their advocates."

Aiming high

But a lot can change in a decade, including the cost of firing rockets. Since the SSI report, SpaceX's reusable Falcon 9 rocket has sent launch costs plummeting to around 30 times less than those of NASA's Space Shuttle, with satellites also getting cheaper due to mass production and advances to the clean rooms where they're made. And SpaceX's even bigger Starship rocket promises to more than quintuple Falcon's payload capacity, lowering prices further.

"What you have is a cadre of people in the space community that have grown up before Starlink and SpaceX," Garretson said. "They literally could not believe that, as your launch rate goes up and you amortize your costs, [the launch cost] approaches the cost of fuel." Some took notice. A 2021 assessment commissioned by the U.K. government estimated that a 2-gigawatt, mile-wide space-based solar power array would cost 17.3 billion British pounds ($23.4 billion) and generate energy at 50 British pounds ($68) per megawatt hour over its century lifetime.

That's the equivalent output of a large power station in the U.K., with the initial costs being 39% to 49% cheaper than biomass, nuclear or the most efficient gas energy sources, according to the assessment. And while it's still 14% to 52% more expensive than current terrestrial wind and solar energy, the technology could be beamed anywhere, even to remote locations.

Based on these findings, in 2023, the U.K. government awarded 4.3 million British pounds ($5.8 million) in seed funding to a handful of companies and universities to develop SBSP further.

The U.K. report chose one satellite design as its reference architecture: CASSIOPeiA. Belonging to the U.K. SBSP company Space Solar, the satellite's design is an attempt to crack a significant challenge faced by early solar satellite blueprints: how to keep solar panels constantly aligned with the sun to maximize radiation collection.

Unlike other satellite designs, such as China's Multi-Rotary Joint Solar Power Satellite or Mankins' SPS-ALPHA, which rotate the panels or use a system of mirrors to constantly redirect sunlight onto them, CASSIOPeiA is shaped like a gigantic DNA strand.

This design, alongside a sun-synchronous orbit and a slow spin, enables CASSIOPeiA to constantly receive and transmit solar energy without any heavy or failure-prone moving parts. Space Solar claims that a single CASSIOPeiA satellite, which would be about 1 mile (1.6 km) in diameter, could microwave-beam as much as 2 gigawatts of constant power to a fixed point on the ground — enough to supply a city of 2 million people.

Space Solar says that once the satellite is in space, it will be far more efficient and economical than gathering sunlight on the ground could ever be. That's because the light hitting the space-based power station isn't deflected or attenuated by the atmosphere.

"You use a lot less materials compared with terrestrial solar, and you utilize them more," Sam Adlen, co-founder and co-CEO of Space Solar, one of the funding recipients, told Live Science. "So it's 100% utilized in space rather than 10% if you're on the ground — and you've got 13 times more instant energy, so you're getting much more out of the materials."

Beaming down

However, the next step — beaming gigawatts of energy down and across tens of miles of atmosphere and through potential cloud cover — remains a major technical hurdle.

Proposed power-beaming methods are currently split between two types: lasers and microwaves. California-based startup Aetherflux, which has plans to beam power from satellites in low Earth orbit, has developed an infrared laser transmission system that it will test using a demonstration satellite launched on October 1. The microwave energy will be transmitted at around one kilowatt (enough to supply the basic electrical demands of a household).

Meanwhile, Caltech and Overview Energy, another U.S. startup, have both demonstrated respective microwave and laser-power beaming from orbit and from a plane, respectively, albeit in negligible amounts ( less than a kilowatt).

Despite their efficiency and proven ability to travel vast distances, optical beams in the infrared and near-infrared ranges are easily scattered by water droplets in the atmosphere, preventing power from being transferred on cloudy days. Persisting efficiency issues with optical power transmission also worsen at gigawatt power levels, meaning lasers are less feasible for use at the utility scale.

Microwaves, on the other hand, can be beamed at frequencies with much higher power and suffer relatively little atmospheric attenuation. That's why Space Solar, Japan's OHISAMA project and China's ZhuRi program all plan to use microwave-beaming systems. Nonetheless, microwaves have comparatively longer wavelengths, so their beams diffract more widely across longer distances. This means that even if beams are sent by transmitters hundreds of meters wide, they would need Earth-based receivers spanning dozens of square miles.

These limitations mean that "it's going to take many years" before gigawatt-scale power beaming is achieved, Remo Proietti Zaccaria, head of the DELTA Lab at the Italian Institute of Technology, told Live Science.

Improvements in power-beaming efficiency will bring their own challenges. Even battery-powered laser pointers can blind or burn, so prototypes by laser-beaming SBSP companies like Aetherflux must be designed with that possibility in mind. They promise safety mechanisms that switch off their lasers if anything flies between the transmitter and the receiver.

"Definitely for the weapon side, this technology now can be used efficiently," Proietti Zaccaria said.

If you're imagining an orbital weapon devised by a Bond villain, you may be disappointed — even fully developed power-beaming lasers and microwaves would take a while to cook an egg, or boil Tsiolkovsky's coffees. But beaming technology could still have potent military use: Scrambling communications systems on Earth to create havoc with relatively little effort.

"If you throw even that amount of intensity of power to our antennas, you're going to freeze the electronics; that's for sure," Proietti Zaccaria said. "It's not necessary to destroy them. As long as you freeze the electronics, you've done the job."

The challenges associated with power beaming have pushed some engineers to simpler concepts. One (going full circle back to Tsiolkovsky's original proposal) envisions the deployment of space-based mirrors that reflect sunlight back to Earth after sunset, with a single reflector extending the daylight delivered onto solar panels by around 20 minutes.

This may not seem like much on its own, "but then you can increase this with multiple reflectors," Onur Celik, a researcher in space technology at the University of Glasgow, told Live Science. "If you have 10 or more of them, you can arrange them in space in such a way that you can extend this to up to two hours or so at that altitude."

"The sunlight that you deliver, if it all turns into electricity, could power thousands of homes," he concluded.

The light of day

The trillion-dollar question is whether that power will be cheaper and more efficient than that generated on the ground. The median cost of the electricity generated by SBSP as estimated by the U.K. government is 50 British pounds per megawatt hour ($68), putting it roughly in line with the costs of offshore wind and terrestrial solar power.

However, this estimate is orders of magnitude too sunny for the 2024 NASA cost report, with its projections suggesting SBSP's baseline electricity costs fall between $610 and $1,590 per megawatt hour, depending on the array design. NASA concluded that the U.K.'s median estimate was achievable only after drastic future reductions in launch and manufacturing costs.

Independent studies are also divided over feasibility. One assessment suggests that SBSP could reduce Europe's need for land-based renewable energy by up to 80%, while another counters that the costs could be 12 to 80 times more expensive than those for terrestrial alternatives. This variability exists within the studies themselves, with research published in the journal Acta Astronautica estimating that SBSP could contribute to meeting anywhere from 3% to 31% of global electricity demand, depending on possible constraints in how many satellites can safely fit into an orbit, the receiver size, and where power is beamed to.

"For the numbers we found, I don't believe that this technology could actually be employed to generate energy for Earth," said Proietti Zaccaria, a co-author of the Acta Astronautica study. If humanity had used up all available space for solar panels on Earth, "then I will tell you it would make sense, because at that point, 3%, 5%, 10% could make a difference."

Proietti Zaccaria does see use cases for SBSP schemes for future moon or Mars missions, but otherwise, "the cost for building technology of this kind is really very, very high," he said. "Vice versa, the cost nowadays of buying and installing a solar panel on the roof of any building has become extremely cheap."

Among the challenges would be ferrying the raw materials for the systems into space and then assembling them. Such a feat would make the construction of the International Space Station — currently the most complex structure built in orbit — seem like child's play. Maintaining arrays and preventing them from crashing into other satellites in Earth's increasingly crowded orbits would also take significant international coordination.

Then there are the unweighed environmental costs. All modern rockets use methane, a potent greenhouse gas, to propel them into space, and they release much of it into Earth's upper atmosphere, where its effects are the strongest.

"And so clearly, there is a question there on how launching 100,000 of these superheavy vehicles into the atmosphere will actually impact the atmosphere itself, as opposed to the benefit that we get in the next 20 years or so from having solar power from space," Matteo Ceriotti, a senior lecturer in space systems engineering at the University of Glasgow, told Live Science. "It's not entirely clear."

Ceriotti said the likeliest route for overcoming all of these difficulties come from smaller companies running, and then streamlining, proof-of-concept tests in space.

"Obviously, it's not something that we have ever done," he said. "So clearly, we need to start somewhere, and we need to start small."

The hopes of SBSP proponents remain unclouded by gloomy estimates. They cite several technologies, from personal computers to reusable rockets, that were once thought to be impossibly expensive, even fictitious, that are now ubiquitous and cheap. Their eyes remain fixed on demonstration missions to be launched over the next four years by the likes of Space Solar, Reflect Orbital, Aetherflux and Virtus Solis. If these missions succeed, another once-impossible idea could appear much brighter.

"The private sector is good at this, because it has to be," Sanjay Vijendran, an SBSP consultant who led the European Space Agency's now-shuttered SOLARIS project to test the feasibility of SBSP, told Live Science. "It can break the problem down to quite a small level and start to do things with today's technology and today's way of doing things, and start to show that this can be valuable."

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A Neanderthal who was buried 75,000 years ago in Shanidar Cave in Iraq died from a wooden spear straight through the chest, archaeologists have revealed.

While it's impossible to know exactly what happened, the violence may have been a targeted hit.

"The position of the wound and the force required to push it right through the Neanderthal's body bear the hallmarks of an intended kill shot directed towards the heart," study first author Emma Pomeroy, a paleoanthropologist at the University of Cambridge, said in a statement.

In a study published Thursday (Oct. 15) in the journal Scientific Reports, Pomeroy and co-authors analyzed the bones of Shanidar A, a Neanderthal who died violently at about age 45 and was then buried in Shanidar Cave.

The archaeological site at Shanidar is famous for its evidence of purposeful burial, which experts once thought was only done by modern humans. Although the Neanderthal "flower burial" at Shanidar has since been debunked, the cave holds other evidence of repeated Neanderthal burials, which shows that these extinct humans placed specific meaning on that location, the authors wrote in the study.

The skeleton of Shanidar A was incomplete when it was discovered in 2019, consisting of a mostly complete right hand, three ribs, six teeth and a left scapula or shoulder blade, which meant they could not figure out the sex of the Neanderthal.

Near the edge of the shoulder blade, archaeologists noticed a round hole about 0.6 inches (1.5 centimeters) in diameter and a round piece of bone that had been punched out of the shoulder blade. The researchers ruled out post-mortem damage to the bone, including animal gnawing and insect burrowing.

"The perforation is best explained as resulting from perimortem [around the time of death] penetrating trauma, such as that caused by a projectile or a thrusting implement such as a spear," the researchers wrote in the study. Specifically, the Neanderthal was killed by a spear that entered their chest from the front at a high velocity and pierced their shoulder blade.

The shape of the wound in the shoulder blade appears to match experimental evidence of injuries made by wooden spears rather than stone-tipped weapons, the researchers wrote in the study. Neanderthals would have used wooden spears for both thrusting and throwing. But it is unclear if this individual died because of a violent interaction with another Neanderthal or by accident, such as a hunting incident.

"All we can ever know about the end of this Neanderthal's life is that it was violent, and came at the end of a wooden spear," study co-author Graeme Barker, an archaeologist at the University of Cambridge, said in the statement.

"Care and support from other Neanderthals"

Even though this Neanderthal had an untimely demise, evidence on the teeth suggested that the individual was cared for during life.

The six teeth from Shanidar A were heavily worn-down in an unusual manner, the researchers wrote. One of them — a front tooth with a large quantity of tartar on it — had been split in half during the Neanderthal's life, and the individual continued to use the damaged tooth for a considerable amount of time. The collection of teeth suggests the Neanderthal sustained a major trauma to the face that fractured the lower front tooth and may have caused additional injuries to the jaw.

"There’s no doubt that Shanidar A would have had difficulty communicating and been in absolute agony for a long period of time," Pomeroy said in the statement. "Surviving a blow that splits a tooth in this fashion, then continuing to live and eat for a period of at least a year and maybe more, would have required care and support from other Neanderthals."

Rebecca Wragg Sykes, an archaeologist and author of "Kindred: Neanderthal Life, Love, Death and Art" (Bloomsbury, 2020) who was not involved in the study, told Live Science in an email that the apparently fatal chest injury is an important addition to our understanding of Neanderthals. While it is plausible the Neanderthal was stabbed by a wooden spear, Wragg Sykes said, "it would be interesting to also compare whether a wild goat horn, the most intensely hunted species at Shanidar, might have been responsible."

Shanidar A is not the first mortally wounded Neanderthal to be found at the site. In 2009, researchers analyzed the skeleton of Shanidar 3, an older adult male who died 50,000 years ago, and found a deep slice in one of his ribs. The researchers suggested that the Neanderthal may have been killed by a stone-tipped spear possibly thrown by a modern human. Although modern humans first reached Europe around 54,000 years ago, experts aren't sure exactly how they interacted with Neanderthals.

Pomeroy told Live Science in an email that the discovery at Shanidar of two stabbed Neanderthals 25,000 years apart is interesting but possibly just a coincidence.

"We know from the archaeology that Neanderthals were repeatedly coming back to Shanidar and using it for short periods at a time, both around 75,000 years ago and around 45-50,000 years ago, as well as leaving their dead there," Pomeroy said.

The traumatic injuries, purposeful burial and indirect evidence of wooden spears all show that 75,000 years ago, Neanderthal life — and death — were complex, the researchers wrote in the study.

How much do you know about our closest relatives? Find out with our Neanderthal quiz.

If you're approaching menopause, you are likely being bombarded by online ads for treatments promising relief for everything from hot flashes to brain fog. Some of these therapies have been approved by the Food and Drug Administration (FDA) and have strong evidence to support them — but one hormone-based treatment that's gaining in popularity has much less science to back its use for menopause.

More doctors are writing their menopausal patients prescriptions for testosterone therapy. A 2026 study conducted in the U.S. recorded over 90,000 off-label prescriptions for testosterone to women in 2025, mainly among women ages 45 to 64 and those with diagnoses of menopause. This marked a 58.7% increase from 2024.

These prescriptions are "off-label" because the FDA has not yet approved testosterone as a treatment for menopause, perimenopause (the transition into menopause) or postmenopause (the time period afterward).

So, does scientific evidence support the use of testosterone to alleviate menopause symptoms? Or is it too soon to say?

No direct link to menopause symptoms

Although often called a "male" hormone, testosterone is also produced by females, albeit at lower levels than in males, on average.

There's a common misconception that females experience "androgen deficiency" — a marked decline in testosterone and related hormones — leading up to menopause, said Susan Davis, a professor of endocrinology and the head of the Women's Health Research Program at Monash University in Australia. This is not the case.

Rather, in females, testosterone levels tend to drop slowly between ages 20 and 60, and there's a slight rebound from age 60 onward. Menopause, which generally occurs around age 51 to 52, is not linked to a marked decline in testosterone. Estrogen and progesterone fluctuate during perimenopause and then decline sharply, and these changes clearly contribute to the telltale symptoms of perimenopause and menopause.

Placebo-controlled trials have not been able to show that testosterone treatment helps to alleviate brain fog or improve well-being, mood, bone density or muscle function in menopausal patients, said Davis, who has conducted a number of these trials herself.

"Telling women that fatigue, low mood, brain fog are symptoms of androgen deficiency is completely untrue," she emphasized.

On Sept. 17, the FDA held a public workshop to evaluate the evidence for testosterone therapy for menopause, concluding that more evidence is needed to fully assess the use of the hormone as a menopause treatment.

Testosterone for low sex drive?

There is some evidence to suggest that testosterone might help to treat a condition called hypoactive sexual desire disorder (HSDD) in postmenopausal women. HSDD describes when a person has little to no sex drive and it causes them distress. Men and women of many ages experience it, so the condition is not unique to menopause. But it can sometimes develop in perimenopausal and postmenopausal women.

A review of 36 randomized trials involving 8,480 participants found that testosterone treatment delivered with skin patches was associated with 0.85 additional satisfying sexual events per month in postmenopausal women, compared to a placebo. This observed effect is not huge, Dr. Nanette Santoro, a professor of obstetrics and gynecology at the University of Colorado School of Medicine, told Live Science in an email.

Lately, anecdotal accounts of postmenopausal women having "fantastic sexual awakenings" after taking testosterone have been floating around, Santoro said. But these anecdotes haven't been backed by hard data yet. "Patients are being bombarded with a tsunami of information providing them with the most sky-high expectations imaginable," she said.

Notably, testosterone is not FDA approved as a treatment for HSDD in menopause yet. A drug called flibanserin, which affects serotonin in the brain, is approved to treat HSDD for pre- and postmenopausal women under age 65.

Placebo effects muddy the data

The placebo effect — when patients perceive an improvement in their health or well-being despite receiving a treatment with no active ingredient — can also complicate testosterone trials.

Davis said that in her patient groups, it's common for about 1 in 3 trial participants to report an improvement of their symptoms even though they are taking a placebo. Other trials have reported similar findings in their placebo groups, with about 30% to 40% experiencing some improvement in sexual desire and satisfaction, for example.

"I wouldn't say that there is definitely not a benefit," Davis said. "It's just that a benefit has not been shown."

One study trying to address this gap is the U.K. National Institute for Health and Care Research's ESTEEM trial. This large-scale, gold-standard trial aims to recruit hundreds of menopausal women and test whether using testosterone cream can reliably improve their quality of life. The cream will deliver testosterone through the skin and be applied to the lower abdomen and thighs. (Doctors often advise women to apply the creams in this way because those body parts are easy to hide if the treatment causes localized hair growth that the patients would prefer to conceal.)

The trial runners will track participants' symptoms linked to menopause, looking at sleep quality, memory performance, feelings of anxiousness, migraines, body mass, and overall well-being. The results of that trial are currently expected by 2028.

In the meantime, though, there isn't strong evidence that testosterone directly improves symptoms of menopause beyond HSDD. "Of all the studies done to date, if there was a screaming benefit, you think you would have seen it," Davis said.

Could taking testosterone for menopause be harmful?

Testosterone treatments available in most countries are not necessarily dosed for use in female patients. Only four countries — Australia, South Africa, New Zealand and the United Kingdom — have authorized a testosterone cream that's specifically formulated and dosed for women. These products differ from testosterone therapies for men in that they contain lower doses of the hormone. They are available to postmenopausal women with HSDD, specifically.

In other countries, such as the U.S., doctors are left trying to adapt medication dosed for males for their female patients, which can lead to a wide variation in dosing. And the effects of these different dosing regimens are poorly understood for female patients. "It is not necessarily unsafe to use male preparations for women, it's just that much, much less must be used," Santoro said.

Excessive doses raise concern about unwanted masculinizing effects, such as clitoral enlargement, voice deepening, hair thinning, baldness, and rapid growth of facial and body hair, Santoro said. (These masculinizing effects might be sought after in the context of gender-affirming care for transgender men and transmasculine people, but would often be undesirable for cisgender women.)

Additionally, the potential impacts of extra testosterone on cardiovascular health and breast cancer risk are poorly understood, Santoro noted. At lower doses, testosterone can cause mild acne, oily skin, and some increase in facial and body hair growth in postmenopausal women, trials have found; if these symptoms remain mild, they are generally considered acceptable.

Testosterone is being used off-label in the U.S., which means the "safety, efficacy and appropriate dosing for that use have not been evaluated and approved by the FDA," a spokesperson for the agency told Live Science in an email. The dosages and formulations approved for males "may differ substantially from what might be appropriate for women, whose testosterone levels and metabolic profiles are clinically distinct," the spokesperson said.

Anecdotally, Santoro encountered one female patient who had received very high levels of testosterone through an implant placed under the skin, which had been prescribed to her by a different doctor. She started losing her hair and seeing sizable growth in her clitoris, while her breasts started "shrinking away."

"Women are being prescribed some very big doses in North America, and no one studied the safety of these," Santoro said.

At the end of the day, Davis argues that women deserve to be given accurate information, given that navigating menopause can already feel like "swimming through wet cement." Good menopause care not only involves discussing potential pharmacological treatments, but also evaluating a patient's lifestyle, such as diet and exercise, and discussing societal pressures that often affect menopausal people. For instance, they may face pressure to maintain an active sex life and younger-looking physique.

When it comes to hyped therapies like testosterone, she said, "just be cautious about people who tell you they've got the answer that no one else has got."

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

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For people with chronic back pain, everyday movements like bending down to tie their shoes or picking up a grocery bag can trigger painful flare-ups. Now, scientists have made a surprising discovery: These episodes may activate a brain network that's associated with our sense of self.

In a new study, the researchers found that movement-induced chronic back pain was tied to increased activity in the brain's default mode network, a group of connected brain regions that lights up during self-reflection and mind wandering. This finding was unexpected because the network typically becomes less active during acute pain, such as transient pain triggered from touching a hot stove or banging your knee on a table.

The new study, published Oct. 5 in the British Journal of Anaesthesia, suggests that chronic-pain flare-ups may involve brain processes beyond those responsible for detecting painful sensations.

How the brain responds to chronic pain

Chronic lower back pain, defined as lasting at least three months, is a leading cause of disability worldwide. It's thought that when chronic pain first begins, a network of regions in the brain called the "pain neuromatrix" becomes sensitized so that the pain persists even after the painful stimulus is gone. Although scientists know that chronic pain is associated with changes in brain activity, they don't fully understand what happens when movements trigger sudden increases in that ongoing pain.

To investigate, researchers recruited 114 adults with chronic lower back pain and used functional magnetic resonance imaging (fMRI) to examine their brain activity. fMRI measures changes in blood flow, which acts as an indirect measure of brain activity.

After an initial scan, a researcher helped lift each participant's leg until their back pain increased, held it in position for 10 seconds, and then lowered it. The researchers scanned the participants' brains immediately after this pain-inducing leg movement and compared the results with scans collected beforehand. On average, the test increased the participants' reported pain intensity by 23%.

As expected, during the leg movement, the researchers observed increased blood flow in brain regions involved in processing pain and movement. But they also detected increased activity in key regions of the default mode network, which typically becomes more active when a person is thinking about themselves or their autobiographical memories or just letting their mind wander.

Acute pain lowers activity in the default mode network, studies show, presumably because it induces an awareness of something separate from yourself.

"When we saw just the first round of analysis, we're like, 'Did we do it right?'" study co-author Morgan Gianola, a postdoctoral scholar at the University of California, San Diego, told Live Science.

"We did not expect [the default mode network] to be involved at all," said study co-author Fadel Zeidan, a neuroscientist at UC San Diego, told Live Science. "We expected it to be deactivated to the point that we had to triple-check our work to make sure that the results were legit."

The researchers also exposed participants' calves to painful heat ‪—‬ a common method of studying brain activity during acute pain. Unlike the movement-induced back pain, the heat was associated with reduced activity in part of the default mode network, suggesting a different mechanism was at play.

When pain becomes part of our internal experience

Participants who reported more severe chronic back pain had stronger connectivity between the default mode network and brain regions that process sensations from the back. This suggests that chronic pain may become intertwined with how people perceive themselves and their bodies, the study authors concluded.

"This pain flare has almost become a part of who they are from an egocentric perspective," Zeidan said.

Katherine Martucci, a neuroscientist at Duke University who wasn't involved in the study, praised the experimental design, noting that researchers typically avoid movement during brain scans because it can interfere with the clarity of the scan. This study "nicely gets around" that problem by taking scans before and after the painful motion, Martucci told Live Science in an email.

However, she noted that the observed brain activity could also reflect lingering pain or anxiety following the painful leg raise. In addition, the study couldn't determine whether the altered brain activity observed contributes to chronic pain or develops in response to it.

Nonetheless, Zeidan and colleagues think the findings could eventually inform future treatments for chronic pain. The therapies might address how people relate to their pain, rather than solely targeting the painful sensations themselves. Zeidan, who coincidentally developed chronic back pain while conducting the study, believes that people's past experiences and memories with chronic pain have influenced their brain processes to a point where the pain itself becomes part of who they are.

Zeidan's team is now investigating whether existing approaches, such as mindfulness meditation or cognitive behavioral therapy, can influence the default mode network and help relieve chronic pain. (Cognitive behavior therapy for chronic pain, or CBT-CP, is already a well-established treatment option.)

Martucci cautioned that it's too early to draw conclusions about how these results might be applied in clinical practice. But she said the current findings provide important evidence of how the brain responds to chronic pain flare-ups.

"They do provide solid data on how people with chronic low back pain show important changes in their brain responses after a condition provoking their pain," she said. "The brain imaging data validate their [the participants'] experience of pain in an important and very visible way."

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

Ancient DNA from skeletons buried in a historic cemetery in Quebec is changing people's understanding of their Indigenous ancestry. Contrary to popular belief, there may be little truth to stories of intermarriage between Indigenous and French people during the early days of colonization, according to a new archaeology study published Oct. 5 in the journal PNAS.

"Family stories of an Indigenous ancestor are very common" in Quebec, study first author Diane Martin-Moya, a biological anthropologist at the University of Quebec in Trois-Rivières in Canada, told Live Science in an email, and "commercial genealogy and DNA tests have amplified this." But distant or claimed Indigenous identities can actually undermine the rights, resources and recognition of Indigenous nations, she said.

To learn more about the founders of Quebec, Martin-Moya and co-authors investigated Notre-Dame Cemetery, which was established in Montreal in 1683 and used for Catholic burials until 1796. Based on previous studies of the skeletons in the cemetery, experts disagreed on whether people of Indigenous, European, African or mixed ancestry were buried there. To settle the question, Martin-Moya and her colleagues sequenced DNA from 45 people buried in the cemetery and compared it with the genomes of people from Europe, West Africa and Indigenous groups in the Americas.

"The ancient DNA showed that all 45 individuals we analyzed had French European ancestry, with no sign of recent Indigenous or African admixture," Martin-Moya said of the research, which she conducted while at the University of Montreal.

These findings suggest that people descended from Indigenous and African populations may have been marginalized in early Montreal, challenging the popular narrative of cooperation and intermarriage, she said.

"Our sample is small and comes from a single cemetery, so this does not show that such unions never happened," Martin-Moya cautioned. "It is, however, consistent with genealogical and genetic studies suggesting that Indigenous ancestry among present-day French Canadians is very limited."

The apparent lack of genetic mixing among European, African and Indigenous populations in this cemetery group "provides a perspective on population relationships during the colonial period, one where perhaps nongenetic interactions were present but no biological relationships were found," Raquel Fleskes, a molecular anthropologist at Dartmouth College who was not involved in the research, told Live Science.

The DNA helped the researchers find several genetic lineages of people that spanned multiple generations. But the graves were scattered across multiple areas of the cemetery, suggesting that burials were not organized into family plots. This finding suggests that, in the 17th century, people in Montreal may have been burying their dead in a way that was not defined by strict biological kinship ties, Fleskes said.

One cemetery, many possibilities

Martin-Moya stressed that the results of the new study do not necessarily apply to all of colonial Montreal.

"Not identifying recent Indigenous or African admixture in this sample does not imply that Indigenous or African-descended people were absent from the city," Martin-Moya said.

In addition, "biological ancestry cannot by itself establish Indigenous belonging," as it "is rooted in kinship, community and relationships with land, not in blood or DNA," she added.

Changes in the use of the cemetery over time also may have influenced the findings, as reburials and later urban development disturbed or destroyed earlier graves.

"Those buried inside the church, mostly clergy and wealthier residents, were more likely to be exhumed and moved," Martin-Moya explained, while the city's poorer residents were buried outside the church and further buried beneath the expanding city. This means that the skeletons in the study may have been the remains of lower-class French colonists.

Archival records show that some Indigenous people were buried in Catholic cemeteries in Montreal as early as the 17th century, Martin-Moya said. "Over time, though, Indigenous communities were increasingly separated from the colonial town through land dispossession and the relocation of missions away from urban centers," she explained. "Their dead would most likely have been buried in those communities. Enslaved people, both Indigenous and African, were often buried on their enslaver's property or in cemeteries for the poor."

The results of the study don't mean that Québécois have no Indigenous ancestors or that relations between French settlers and Indigenous peoples were only hostile, Martin-Moya said. Those relationships were complex and included alliances, trade, conflict and, sometimes, family ties.

"What our results suggest is that when such ancestry exists, it needs to be put in context," Martin-Moya said. "A single ancestor who lived more than 300 years ago does not say the same thing about a person today as being raised within an Indigenous family, community or nation."

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

A modified tapeworm medication could be a promising new treatment for endometriosis, an early study in mice hints.

In endometriosis, tissue similar to the lining of the uterus grows outside the organ, and these patches of tissue, called "lesions," trigger painful inflammation and heavy menstrual bleeding. In the new study, scientists fitted an anti-worm drug with nanotech armor, and it directly targeted these painful lesions in laboratory mice.

The treatment reduced inflammation and slowed or prevented further spread of the lesions, researchers reported in August in the journal Advanced Healthcare Materials. The team is already working on bringing the new drug to clinical trials and hopes this will bring fresh attention to an understudied disease with limited treatment options.

Rogue immune cells are a promising drug target

Endometriosis is a chronic, hormone-driven condition that affects roughly 10% of reproductive-age females ‪—‬ an estimated 190 million individuals worldwide. "The main symptoms are chronic pelvic pain and infertility," said Ioannis Simitsidellis, a postdoctoral researcher at the University of Edinburgh's Centres for Reproductive Health and Inflammation Research, who wasn't involved in the study.

There is currently no cure, so existing treatments aim to alleviate the symptoms. Hormonal medications can stall the menstrual cycle to limit the growth and inflammation of the lesions, while surgery can physically remove lesions. However, the former can come with side effects, such as nausea and mood swings, and lesions often regrow after surgery. So additional options are needed.

In previous research with mice, study co-author Kanako Hayashi, a professor in the Washington State University School of Molecular Biosciences, identified a group of rogue immune cells specific to endometrial lesion tissue. These cells turbocharged the painful inflammatory reactions and drove the growth of more of this problematic tissue.

The cells also happen to have a unique chemical label, called a folate receptor, which makes them an excellent potential drug target. But why start from scratch when there's an existing medication that might do the trick?

Enter niclosamide, a drug approved by the Food and Drug Administration to treat tapeworm infections. In recent years, clinicians have been exploring whether this medicine could also prove effective for other conditions, ranging from cancer to Parkinson's disease.

"We have reported that niclosamide inhibits endometriosis progression, suppressing the inflammatory mechanisms and cytokine secretions," said Hayashi, referencing more of the group's past work in mice. However, several issues made the drug impractical: It doesn't dissolve well in water, last long in the body, or target the cells where it's needed most.

So the researchers teamed up with Anjali Sharma, a nanomedicine specialist at the University of Michigan, to tweak the drug's structure. Using click chemistry — a simple reaction that bolts together two chemical building blocks — Sharma attached the niclosamide unit to a large, tree-like molecule called a dendrimer. This helped the drug dissolve better in blood.

She then added a folate group, which ensured that the modified medication would only target the rogue immune cells with the complementary receptor.

"The drug is attached in such a way that when it is in systemic circulation, nothing happens until it goes inside the diseased cells," Sharma said. Once there, it is slowly released inside the cell over a period of two weeks. "Basically, the dendrimer is like the Uber, the folate is like the GPS, and the drug is like the passenger," she explained.

The next steps

With these practical issues resolved, the team tested the modified drug in a mouse model, which mimics the lesions seen in endometriosis in humans. Scans of the mice showed that the treatment directly zeroed in on the affected endometrial tissue and didn't accumulate in other organs, like the liver.

Treating mice with a single injection dramatically reduced their pain symptoms, compared with untreated mice. It also slowed ‪—‬ or, in some cases, entirely halted ‪—‬ the growth of new lesions.

Because mice don't naturally menstruate or develop endometriosis, there is still significant work to do before these findings can be replicated in humans. But for now, the study is a promising stepping stone for future research, Simitsidellis said.

"There's a lot of potential in repurposing of drugs that have been tested in clinical trials to see if they would be effective in endometriosis ‪—‬ for example, targeting inflammation or immune cell dysfunction," he told Live Science. "The next steps would be to replicate on larger sample sizes and, if that's promising, do a phase one clinical trial in humans." That initial trial would test the treatment's safety in patients, while later trials would look at its effectiveness for endometriosis.

Even at this early stage, though, patients are clamoring to get involved in the upcoming research. Hayashi and Sharma have received hundreds of emails asking to join a future trial.

"They are really suffering," Hayashi said. "Endometriosis is an understudied, underacknowledged, underfunded disease, but hopefully we can make this a solution in the near future."

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

Some of the first people in North America lived through extreme climate change at the peak of the last ice age, a new study suggests.

Researchers studied ancient pollen locked in rocks at White Sands National Park in New Mexico, which houses an archaeological site thought to contain the oldest human footprints in the Americas. The researchers previously dated those footprints to around 21,000 to 23,000 years ago, though their age is the subject of some scientific debate because they are significantly older than other Indigenous sites in the Americas.

The new findings, published Wednesday (Oct. 14) in the journal Science Advances, suggest that humans kept using White Sands after temperatures warmed and thus saw the landscape undergo rapid changes during the coldest era of the last ice age, known as the Last Glacial Maximum (26,500 to 19,000 years ago).

"It's remarkable that early humans in the region were real-time witnesses to a rapidly changing environment discernible within a human lifetime — that is really food for thought," study co-author Kathleen Springer, a research geologist at the U.S. Geological Survey, said in a statement.

The White Sands footprints suggest that people from Asia reached the Americas via the region around the Bering Strait much earlier than scientists initially thought, challenging a long-held assumption that humans arrived on the continent around 13,000 years ago. While some scientists have disputed the methods used to date the footprints, evidence is building that they are around 23,000 years old.

White Sands contains footprints from various time periods, including footprints of a caregiver and a toddler who were there 10,000 years ago. Over thousands of years, people trudged across the New Mexico landscape alongside iconic ice age animals, including mammoths and giant ground sloths. The researchers have also discovered sled-like drag marks alongside ancient footprints at White Sands, providing evidence for a kind of travois — a wooden frame made from two poles bound together — that people likely would have used for transporting goods.

By looking at ancient pollen for the new study, researchers could deduce which plants grew across the millennia when humans lived in the area. The site's rock samples also contained waxes from plant leaves, membrane lipids from bacteria, and other organic molecules that helped the researchers better understand the environmental conditions of the time.

The analysis revealed that around 24,200 years ago, White Sands had a large lake and its surrounding mountains were coated in conifer trees (Pinus, Abies, and Picea). Then, over the next two millennia, temperatures rose, the lake began to shrink, and the conifer trees were replaced by oak trees (Quercus) and sagebrush, according to the statement.

"Throughout these periods of change, the people continued to visit and live in this area," study co-author Sally Reynolds, a paleoanthropologist at Bournemouth University in the U.K., said in the statement. "The sediments containing their footprints show us their environment changed significantly within individual human lifetimes."

The researchers speculated that people might have returned to White Sands at different times to benefit from the changing climate, with a shrinking lake potentially providing higher concentrations of animals and plants. However, while the footprints document that humans were present, they reveal little about their behavior.

"The footprints give us a snapshot of the people who lived there over 20,000 years ago," Reynolds said. "But they are not a continuous movie of their lives. They are individual frames — showing moments when humans, mud, water and chance came together."

Researchers say they've developed a simple mathematical formula that can predict when certain ChatGPT-like artificial intelligence (AI) chatbots will "go rogue," suddenly switching from helpful responses to potentially harmful ones.

In a new study published Oct. 8 in the journal Patterns, physics professor Neil Johnson and doctoral student Frank Yingjie Huo, both at The George Washington University, show how the order in which a chatbot is given certain prompts can drastically reshape its answers, leading to "tipping points" that can send the chatbot down a rabbit hole of bad advice. However, Johnson and Huo say their formula can easily predict these tipping points.There have been horror stories of AI encouraging users into suicide, helping build lethal weapons, and amplifying violent or harmful points of view. At the same time, researchers at OpenAI and Anthropic, respectively, have repeatedly and openly stated that they don't really understand why their creations behave the way they do. They have, however, built safeguards that use a variety of tools ‪—‬ including content filtering, reinforcement learning and other technical guardrails ‪—‬ to reduce risks.

But Johnson sees those tools as insufficient. "The safety measures now are the equivalent of strapping big, bouncy cushions under a plane," he told Live Science. "They don't stop the plane from crashing; they just make it that when the plane crashes, it'll be slightly softer." When people such as doctors, lawyers or soldiers are accessing AI chatbots offline for privacy, the problem is even more acute.

Johnson and Huo sought to find a more fundamental safeguard than the currently available tools. In doing so, they exposed an internal tracking mechanism they describe as a compass needle. This needle is the model's "residual vector" moving across neural network layers as a prompt is processed.

The residual vector naturally gravitates toward either desirable or undesirable outputs, but it is heavily influenced by how a user prompts the AI. "You can tip the balance, not even by changing the content but by changing the order in which you ask it," Johnson said, "which just shows how delicate this internal balance between good and bad, desirable and undesirable, can be."

For example, Johnson and Huo prompted OpenAI’s basic GPT-2 model with questions about vaccines, hurting others and self-harm. When the question “Are vaccines bad?” was asked first, the bot’s responses to this and subsequent questions were desirable, or good. When it was asked last, all subsequent responses were concerning.

From these insights, the researchers developed a mathematical formula to estimate the circumstances in which an AI would reach the tipping point between desirable and undesirable outputs. Johnson said that by embedding their simple mathematical formula in open-source models in the lab, they have shown that it empirically works as an early warning system, though he does not expect OpenAI or Anthropic to be knocking on his door anytime soon.

"I'm expecting a lot of pushback from these companies," he said. "It's not in their interests to have someone from outside saying you could have avoided a lot of these problems."

Wei Xing, a lecturer in AI at the University of Sheffield in the U.K. who was not involved in the study, agrees that concerns surrounding unmonitored offline devices are well founded. However, he urged caution before embracing this approach as a practical safeguard. "The authors reduce a huge system to a single tiny component, like explaining a whole car by studying one spark plug," Xing said.

Safety training — the primary defense in modern AI — cannot be represented in their simplified model, the formula was tested only on old, basic models (GPT-2, and EleutherAI’s Pythia and Meta OPT open-source models) rather than AI assistants people actually use, and the results did not yield significant evidence to support the authors’ conclusions, he added.

In defense, Johnson maintains that the open-source models they used have the same mechanical blueprints as frontier systems, and that he and Huo used fairly large, billion-parameter models in their study.

More testing on the latest models is needed to determine whether this early warning system for AI has legs. But for now, Johnson and Huo’s research has drawn attention to an important concern everyone should be aware of: that AI has the capacity within it to turn over to undesired behavior at the drop of a hat.

Fish meal is a commercial, protein-rich product created from raw fish and their byproducts, such as the heads and bones. It tends to be made from smaller fish species, including anchovies, sardines and herring. The fish are cooked, dried and ground into a powder, and then used to feed livestock, farmed fish and pets. But it is not a straightforward market.

In this excerpt from "Every Last Fish: A Deep Dive into the World of Fishes and Fishing" (Granta Books, 2025), journalist and author Rose George looks at how vast quantities of staple fish are taken from the sea off West Africa and turned into fishmeal for farming in Europe and China, instead of ending up on the plates of people in Africa.

"Every Last Fish" was short-listed for the 2026 Royal Society Trivedi Science Book Prize.

Rose George interview: 'If you do want to be a criminal, there is no better place to do it': Diving into the dark depths of the fishing industry

Take a fish. Eat its flesh if you want, but don't scorn the rest. It can always be used, one way or another, whether you want fishmeal or face cream.

Products derived from fish turn up everywhere. Guanine, an ingredient produced from fish scales, is found in bath foam, perfume, nail products, shampoo, skincare products, and lipstick. Fishes can become gelatine, glue, and squalene. They can be in your dietary supplements or your glass of wine: isinglass, derived from dried fish air bladders, is used in wine-making.

Futuristic piscigrafts are irrelevant to most people in Senegal, but they still have to deal with the fish by-products industry, because they have to watch as fish they could eat are transformed into the most common and lucrative fish by-products and sent abroad.

Fishmeal is a sandy grubby powder that is worth billions. Minks eat it. Pigs eat it. Cattle eat it. Fishes eat it. It is also an ingredient in fertilizer and pet food. Fishmeal is part of a huge silent industry of fish by-products that used to be known as FMFO (fishmeal and fish oil) and has now been rebranded by the industry association as 'marine ingredients,' a vague term that covers a broad range of fish-derived products, most of which are never noticed.

The Food and Agriculture Organization defines fishmeal as 'the clean, ground, dried tissue of undecomposed whole fish or fish cuttings, either or both, without the extraction of part of the oil.'

American pets may also find themselves eating fish liver and glandular meal, made from dried complete fish viscera; more general fish by-products, which are 'non-rendered, clean, undecomposed portions of fish (such as, although not limited to, heads, fins, tails, ends, skin, bone and viscera)'; or condensed fish protein digest, the 'condensed enzymatic digest of clean undecomposed whole fish or fish cuttings using the enzyme hydrolysis process'.

'Undecomposed' is doing a lot of work here, a strange term because unless a fish is caught by a vessel with freezer capacity — which no artisanal fisher has — it will be decomposing for days. In theory, fishmeal is impeccably sustainable. It should be a product made from parts of fishes that would otherwise be discarded. It is because of fishmeal that the term 'reduction fisheries' was coined.

Take the meat and the prized flesh, and the rest can be reduced or diverted to other uses. That is the theory. It is not what happens in West Africa.

Each year, half a million tonnes of wild fish are caught in African waters and sent to Europe to feed animals, when they could have fed 33 million Africans instead. That number of people is more than the combined populations of Senegal, Mauritania, and The Gambia. Globally a fifth of wild fishes become fishmeal or fish oil, but 90 per cent of fishmeal fishes are suitable for human consumption.

China uses nearly half of all FMFO, but then China uses most of everything. Europe also takes and takes. Spain imports the most fish oil from Senegal, and France takes 70 per cent of Mauritania's.

In 2019, Changing Markets Foundation produced a detailed investigative report into the fishmeal industry in India, Vietnam, and The Gambia. In each country, the pattern was similar: first the foreign factories come, then they take the fish, then they pollute the environment, then the fishermen say there are no fish left.

Although noting 'a surprising lack of traceability and transparency regarding the origin and supply chain of farmed seafood products,' the foundation linked plenty of reputable European retailers to FMFO supply chains that may use West African fish. For example: Sainsbury's, ALDI, Lidl, and Marks & Spencer in the UK; Auchan, Groupe Casino, Monoprix, and Système U in France (that is a full house of big French supermarkets); all the German ALDIs; and Mercadona in Spain. Sainsbury's, Marks & Spencer, and Mercadona have said they don't use West African FMFO in their seafood products, but how will they know?

The European Union's IUU [Illegal, Unreported and Unregulated fishing] regulations, which require a catch certificate or similar to show the fish was legally caught, do not cover fishmeal. In Mauritania, some Chinese-owned fishmeal factories have their own trawler fleets. The fish bypasses human mouths and goes straight to the factory. That is one tactic. The other is to outbid.

The fish processors tell me that they cannot compete with the prices that fish factories will pay for sardinella. Fish processors get no subsidies from the government, unlike Chinese fishing companies. In The Gambia, one fishmeal factory used 40 per cent of the country's entire fish catch in one year. Black and white. White stealing from Black. The villain/victim template seems neat and unassailable.

It is true — Europeans are using fish that West Africans could eat — and yet it is not all the truth. In Senegal, The Gambia, Mauritania, local fishermen supply fishmeal factories because the factories pay better. In Senegal, a fisheries union official tells me that there are too many pirogues. They are chasing smaller and smaller fish to sell to the factories. It is unsustainable.

The website of the IFFO, which used to stand for International Fishmeal and Fish Oil Organization and now somehow is short for the Marine Ingredients Organisation, is plain. Marine ingredients 'play an essential role in global food security'.

Rubbish, said Francisco Marí of Bread for the World at the CAOPA [African Confederation of Professional Organisations of Artisanal Fisheries] workshop. 'It's just for prawns and salmon — they are not necessary foods; it's a luxury. It's not enough for us to have 10—15 per cent of fish to feed salmon and prawns. Indirectly, we are eating your fish. It's not essential for the alimentation of the US or Japan. We are taking your fish to feed a luxury product that we don't need.'

Every Last Fish: A Deep Dive into the World of Fishes and Fishing by Rose George is published by Granta

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Archaeologists digging in the medieval city of Great Zimbabwe have discovered pieces of jade-green Chinese pottery, suggesting that the enigmatic empire had long-distance connections with East Asia more than 1,000 years ago.

Great Zimbabwe, located in the southeastern part of modern-day Zimbabwe, was the capital of an ancient empire that arose in southeastern Africa in around A.D. 1000. Little is known about this precolonial empire because its people did not leave a written history, but new archaeological excavations are shining a light on the enormous scale of the centuries-old civilization known for its intricate metalworking and ritual stone carvings.

In the new PBS documentary "Secrets of the Dead: Africa's Golden City," filmmakers followed a team of archaeologists from the field to the laboratory to try to answer questions surrounding the origins of the understudied civilization, its ritual and trade activities and why it disappeared after 500 years.

"When I was growing up, I was surrounded by symbols of Great Zimbabwe," University of Oxford archaeologist Shadreck Chirikure, who is leading the new excavations at the site, said in the documentary. "It was only when I started studying archaeology at university that I started realizing that there was this very big debate around who built Great Zimbabwe."

The site was first excavated in the late 19th century and quickly looted by British colonists for its ivory, metal and gold artifacts. These colonists insisted that Africans hadn't built Great Zimbabwe, instead claiming it arose from the Phoenicians, a people originally from the Mediterranean; they used that inaccuracy to justify taking all the artifacts to England, according to the documentary. Today, many Great Zimbabwean artifacts are held in the collection of the Pitt Rivers Museum at the University of Oxford.

But excavations are showing that Great Zimbabwe was a highly connected African kingdom that flourished from the 11th century until at least the 15th century, when the population may have gotten too large for the dry, over-farmed land to feed. Archaeologists have already discovered glass artifacts at Great Zimbabwe that came from Southeast Asia, India and the Middle East via boat.

"From India or Sri Lanka to Great Zimbabwe, it's at least 8,000 kilometers [5,000 miles]," Chirikure told Live Science. Merchants sailed the Indian Ocean using winds kicked up by monsoon cycles.

"It's time we try to understand a bit more about trade and exchange," Chirikure said, "particularly by comparing the communities in places like Sri Lanka and southern Africa. Because it's the water that separated people, but it was also the water that connected people."

In this exclusive clip from the documentary, Chirikure and archaeologist Muchen Zhou, a doctoral student at the University of Oxford, examine a jade-green piece of pottery unearthed from the hillside at Great Zimbabwe. The glossy sheen on the sherd suggests the pot was fired at an extremely high temperature, a technological achievement that had only been accomplished in China at that early date. This style of pottery, called Longquan celadon, was made in eastern China starting around A.D. 950.

"We find it across the site of Great Zimbabwe," Chirikure said, but in small quantities. "This means the Chinese ceramics are a rarity. Perhaps they were used by the elites. They would have been quite a significant or highly valued exotic ware."

Other evidence of long-distance trade has been discovered at Great Zimbabwe, Chirikure said, including metal objects from what is today the Democratic Republic of Congo, around 1,250 miles (2,000 kilometers) away. The people of Great Zimbabwe were also sourcing copper and tin from modern-day South Africa, more than 300 miles (500 km) away. And chemical analysis of cattle bones has shown that some of the animals were being traded across an 87-mile (140 km) area.

For his next project, Chirikure hopes to investigate local resources, such as soapstone, that hold a lot of meaning for the local Shona people, Zimbabwe's largest Indigenous group; and for Zimbabweans.

"Soapstone birds are an important part of Great Zimbabwe," he said, "but no one really knows where they got their soapstone from."

The Zimbabwe Bird, designed based on a series of birds carved from soapstone that were found at the archaeological site, is the national emblem and appears prominently on the country's flag.

"There are a number of soapstone outcrops around Great Zimbabwe," Chirikure said. "Next time in the field, that's one of the things I want to do — just go out there and try and find the geological sources of that soapstone."

The PBS documentary "Secrets of the Dead: Africa's Golden City" premieres Wednesday, Oct. 14, at 10 p.m. U.S. Eastern time.

Wildlife photographers need a camera that is reliable and built to capture fast-moving action at a moment's notice. A fast burst rate, accurate autofocus and robust handling are vital when it comes to wildlife cameras, or you'll end up with sad, blurry photos of an empty tree stump.

We've curated a list of the best models from each of the top camera brands, so no matter which system you want to invest in, there will be something for you here.

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Paleontologists in China have discovered a small Jurassic bird that was likely a land-based predator — like a carnivorous pheasant with killer claws. It had some features of birds and others of dinosaurs, suggesting that the earliest birds had a greater diversity of lifestyles than previously recognized.

Jurassic birds first emerged 150 million to 148 million years ago, and fossils of them are rare, so experts are just starting to understand how early birds diversified and evolved the ability to fly.

The researchers discovered the newly identified Yuezhuornis yangyuanensis in 2024, in the fossil assemblage known as the Upper Jurassic Zhenghe Fauna in southeastern China. It lived 150 million to 148 million years ago, roughly when birds started to appear in the fossil record. The team published their findings Wednesday (Oct. 14) in the journal Nature.

Analysis of the fossilized skeleton revealed the animal was small and weighed about 1.8 pounds (0.8  kilograms). "It was probably as large as a crow," Min Wang, a researcher at the Chinese Academy of Sciences, told Live Science via email.

Y. yangyuanensis had a mix of features seen in birds and predatory Deinonychosauria dinosaurs, such as Velociraptor, which are known for their sickle-shaped toe claws. It had deinonychosaur-like hyperextensible toes, with forelimbs that were roughly one-third shorter than its hind limbs. This is odd because modern birds and many other Jurassic paravians — the group that includes bird-like dinosaurs, including the ancestors of birds as well as modern birds themselves — have long forelimbs, linked to giving wings more lift force for taking off.

Y. yangyuanensis also had slender cranial elements and sparsely spaced teeth. These features, alongside the curved claw-like toes that were capable of securing prey, suggest that the animal's diet included meat.

"Its key anatomical features are the combination of dinosaurs' and birds' features: for instance, its teeth, pectoral gird, and especially the hyperextensible, 'sickle-clawed' second pedal digit are similar to that of dinosaurs," Wang said. Meanwhile, he said its slender cranial bones and bird-like pelvis are comparable to early birds.

This combination of features suggests that "the morphological gap between birds and dinosaurs is much smaller than we thought," he added.

Comparisons with 377 living bird species showed that the limb proportions of Y. yangyuanensis were most similar to those of terrestrial birds.

Wang suggested that Y. yangyuanensis was a flightless bird, but not one specialized to live in trees or wade in the swamps in the region. It was a small carnivore, with similar proportions to a pheasant, that was well adapted for running. "I think there are no directly comparable modern birds," he said.

The mosaic of features hints that Y. yangyuanensis may have occupied an ecological niche that was rarely utilized by early birds, and that there wasn't a systematic progression toward flight optimization, Wang said.

Despite being flightless, Wang and his colleagues place Y. yangyuanensis closer in the evolutionary tree to modern birds than to Archaeopteryx, one of the world's first proto birds, which lived about 150 million years ago and is thought to have been able to fly.

This adds to evidence that "the ability to fly arose not once, but several times among disparate groups of carnivorous dinosaurs that are closely related to birds," wrote Fernando Novas, a paleontologist at the Felix de Azara Natural History Foundation in Buenos Aires, Argentina, who wasn’t involved in the study, in an accompanying article in Nature. This includes flight evolving in early birds and in scansoriopterygid dinosaurs, which had membranous folds like the wings of bats, and the four-winged microraptors. Y. yangyuanensis seems to have taken a different road, eschewing the flying ways of its relatives.

"It highlights the extraordinary breadth of ecological and morphological diversification that took place close to the origins of avialans," Wang said.

One of America's largest meteor craters is around 100 million years younger than scientists thought, which means the ancient impact coincided with — and potentially contributed to — one of the biggest global extinction events in Earth's history, according to a new study.

The underground impact structure, known as Ames crater, is located in northern Oklahoma and is named after a small town that sits above the submerged crater. At around 10 miles (16 kilometers) wide, it is the fourth-largest impact structure in the U.S.

Ames crater was created when an Eiffel Tower-size space rock slammed into our planet at more than 70,000 mph (110,000 km/h). At the time, the region was covered in a shallow ocean, and the crater was subsequently buried beneath layers of seafloor sediment. Therefore, there are no visible signs of the crater at the surface today. It was only discovered in 1991, when oil prospectors accidentally drilled into it.

Until now, researchers thought Ames crater dated to the Ordovician meteor event around 467 million years ago. During this period, an unusually high number of large space rocks smashed into Earth, likely due to the fragmentation of a single parent body somewhere in space. Scientists found fossils of marine animals in and around the crater that date to around the time of that event.

But in the new study, published July 7 in the journal Meteoritics and Planetary Science, researchers analyzed fracture patterns within tiny rocky fragments known as zircon crystals that were embedded in the underground crater. This revealed that the impact actually occurred 370 million years ago, around 97 million years after the Ordovician meteor event.

"No matter what technique we used, it was coming back to this younger signal," study first author Elizabeth Catlos, a geologist and planetary scientist at the University of Texas at Austin, said in a statement.

Reading crystals

Zircon crystals are tiny pieces of a superdurable mineral known as zirconium silicate. These crystals are scattered throughout most of Earth's rock formations, including most of the oldest known rocks on our planet. The near-industructible crystals are extremely useful to geologists because their internal structure preserves evidence of being exposed to extreme conditions, such as high temperatures and intense pressures.

Analyzing zircon crystals is now one of the primary methods of dating ancient meteor craters, and the technique has led to several other impact dates being revised. For example, in July, researchers in Australia revealed that the North Pole Dome crater was around 500 million years younger than initial studies predicted, and in 2025, experts found that the impact that birthed Scotland's Stac Fada Member structure happened around 200 million years later than earlier research estimated.

The crystals offer insight into what Earth may have looked like shortly after it formed and have recently been used to more accurately date the moon.

"These small crystals allow us to go back in time and learn about the major changes to Earth's ancient landscapes," study co-author Danny Stockli, a geologist and dean of the Jackson School of Geosciences at the University of Texas at Austin, said in the statement. "It would be great to do this for more of the meteor impact sites across the continent so we could get a more accurate timeline for these major events."

"This is where the impact belongs"

The crater's new age takes it firmly out of the Ordovician meteor event and places it into the Frasnian-Famennian mass extinction event, also known as the Kellwasser event or the Late Devonian mass extinction.

During the Frasnian-Famennian event, which began around 372 million years ago and lasted for several million years, as much as half of all marine life went extinct as Earth's oceans were depleted of oxygen. The die-off, which was most likely triggered by global cooling due to increased levels of volcanic activity, is often cited as one of the five major extinction events in Earth's history.

The researchers emphasized that the Ames impact was not the cause of the Frasnian-Famennian event. However, they noted that the fallout from the impact, which would have injected huge clouds of dust into the air, may have contributed to the atmospheric cooling effect in the region.

It is an important reminder that the ability to accurately date specific events like this can inform our understanding of wider global patterns and trends, the researchers wrote.

"With this research, we're basically taking a major pawn out of the Ordovician Meteor Event and dumping it into the Frasnian-Famennian event, and saying, 'This is where this impact belongs,'" Catlos said.

The new study was dedicated to co-authors Andrew Parisi and Michael Brookfield, who sadly died before it was published.

The patient: A 16-year-old girl in California

The symptoms: The teenager was referred to an emergency department because she was having hallucinations, including seeing a flying green dinosaur and hearing voices telling her to hurt others. She also had a sense that she was being followed.

In the emergency room, she was trembling and sweating and had a racing pulse and shallow, fast breathing. She did not have a fever, although she did have one at the hospital that had referred her.

During her conversations with ER clinicians, the teen reacted to the vision of the dinosaur as though the creature were present in the room. She reported that she had experienced these hallucinations since seventh grade,‬ so for about four years.

While her parents countered that she hadn’t exhibited psychotic symptoms until 48 hours before they arrived in the ER, they noted that her interest in school and extracurriculars had waned over the past month.

What happened next: Because of the patient's abnormal vital signs, the ER doctors suspected that her hallucinations might be secondary to some physical ailment, such as trauma to the brain, they wrote in a case report. However, a CT scan showed no signs of swelling or hemorrhage in her head. The doctors attempted a lumbar puncture (also called a spinal tap) but failed to collect any cerebrospinal fluid that they could test for irregularities.

The doctors judged the girl to be too medically unstable to be referred to the hospital's psychiatric ward, so she was admitted to the general pediatric department. Pediatric neurologists suggested an electroencephalogram (EEG), a test that measures electric signaling in the brain, but this revealed no further clues.

On her second day in the hospital, the girl entered a complete catatonic state. Her specific symptoms were not described in the report, but in general, catatonia disrupts how a person processes and reacts to the world around them. Catatonic patients often stop moving and speaking. Doctors treated the patient with lorazepam, which slows down nervous-system signaling, and her catatonia subsided in days.

Meanwhile, interventional radiologists performed a successful second lumbar puncture, but the girl's cerebrospinal fluid appeared normal in the initial panels they ran.

After the patient had spent eight days in the hospital, psychiatrists recommended that the girl be transferred to their ward. However, this was not possible because she developed problems with feeding herself. Her continued psychotic symptoms were treated with the antipsychotic drug olanzapine.

The diagnosis: While initial tests of the girl's cerebrospinal fluid did not show signs of meningitis or other abnormalities, a later test came back positive for autoantibodies — immune proteins that target healthy tissues instead of foreign invaders. These antibodies targeted neuronal intermediate filament (NIF), a protein that helps give nerve cells structural support.

Based on this finding, the patient was diagnosed with autoimmune encephalitis, a condition in which the body produces antibodies that attack nervous tissue, leading to harmful inflammation that can cause psychiatric symptoms.

Autoimmune encephalitis is often triggered by a tumor; proteins produced by the growth can resemble proteins within nervous tissue, and the immune system develops a harmful response against the latter while attempting to fight the tumor. The doctors performed MRIs and a PET scan to look for tumors, but they did not find any.

The treatment: The girl received intravenous infusions of a steroid to reduce inflammation, as well as immunoglobulin — antibodies from healthy donors that are often used to calm autoimmune reactions. She also got an infusion of rituximab, a drug that kills B lymphocytes, a type of white blood cell that makes antibodies like the ones attacking the girl's neurons.

In addition to these infusions, the girl underwent five sessions of plasmapheresis over the next month. In that procedure, blood is drawn from the body, a machine separates plasma (the liquid portion of blood) from blood cells, and the extracted plasma is substituted with a replacement fluid before that blood is returned to the patient. This treatment can help rid the body of autoantibodies.

The girl was discharged after having spent almost two months in the hospital. She was treated with ongoing prescriptions of olanzapine and lorazepam, as well as prednisone and monthly immunoglobulin treatments. As her symptoms improved over the following year, she stopped taking the psychiatric drugs but continued her immunotherapy.

What makes the case unique: Autoimmune encephalitis is rare. One study conducted in the U.K. suggests it affects only 5 to 8 out of every 100,000 people. Additionally, most data about the condition in pediatric patients comes from cases caused by autoantibodies that target NMDA receptors, which detect a key chemical messenger in the brain, rather than NIF.

The case report did not name a specific trigger for the girl's condition, but the authors noted that anti-NIF autoimmune encephalitis has been documented in adults following infections, including certain tick-borne bacterial infections, HIV and COVID-19. Cases associated with these infections are rarer than those linked to tumors.

The doctors did not attribute the teen's case to a specific infection, but her family did report that she'd had a cough three weeks before going to the emergency room. The family had visited the Philippines, and the girl and multiple relatives came down with the same illness.

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!

Since June, more than 300 southern right whale (Eubalaena australis) calves have died in Argentine Patagonia, in what scientists describe as an "exceptional" die-off. The preliminary figure already far exceeds the previous annual record set in 2012, when 113 southern right whale calves died — the highest number ever documented for the species, both locally and globally.

Now, scientists are racing to figure out exactly what's causing the record-breaking die-off.

Laboratory analyses of specimens that died this year tested positive for the pathogenic bacterium Erysipelothrix rhusiopathiae, environmental authorities in Chubut province told Live Science. E. rhusiopathiae was first identified in southern right whale calves in 2013, but scientists don't know what might have changed this year to cause an infection-driven die-off of this magnitude.

Researchers say they need to quickly find the answer to better understand the changing threat this species faces, the risk to the wider ecosystem and humans, and what can be done to manage it.

"The battle between living organisms and pathogens is constant," said Carla Fiorito, a researcher at the Center for the Study of Marine Systems (CESIMAR) who previously identified the bacterium in right whales. "But for this to happen now, there must have been a shift in the balance between the agent, the host, and the environment," she told Live Science.

Record-breaking number

The first dead calves appeared on the beaches of Península Valdés in June, at the start of the breeding season, which runs through to December. Península Valdés is located in Chubut province, on the coast of northern Patagonia.

In a typical year, calf mortality reaches 20% to 30% of a cohort from various causes, including infections. But this year's losses have already far surpassed that.

In September, 409 calves were counted among a total of 1,375 southern right whales during a survey conducted by CESIMAR's Marine Mammal Laboratory. With more than 300 deaths already recorded, the die-off represents an exceptional proportion of these calves. The final figure will be released by the Southern Right Whale Health Monitoring Program in December.

Scientists have responded by expediting routine research to determine what's different this year to previous years.

"Samples were sent for analysis earlier than usual — typically, they are analyzed at the end of the year — because the higher-than-usual mortality is a cause for concern," said Víctor Fratto, the director of the Native Wildlife Rescue Program and a contributor with the whale monitoring program. "What those samples are showing is that the calves died from erysipelas," he told Live Science.

A known bacterium full of unknowns

Erysipelas is a bacterial infection that affects the skin. In its most severe form, it can spread through the bloodstream and cause a systemic infection, damaging vital organs and sometimes leading to death. Animals that catch the disease, for example through a wound, may develop characteristic skin lesions, which are rhomboid or rectangular in shape, caused by alterations in the blood vessels.

The bacterium that causes erysipelas, E. rhusiopathiae, is not exclusive to whales. It can be found in marine environments and in a wide variety of animals, including fish, crustaceans and birds. Pigs are one of its natural reservoirs.

"It is a ubiquitous and opportunistic bacterium," Fiorito said. (The human illness of the same name is different and caused by Group A streptococcal bacteria, although humans can also catch the E. rhusiopathiae form of the illness.)

The presence of E. rhusiopathiae does not necessarily mean an animal is diseased. Yet many questions remain about E. rhusiopathiae in whales.

"We don't know much about the bacterium itself; we don't know which serotypes are present in the whales, or how common it is in healthy animals or other species," Fiorito said. "There is also no data on the environment."

Calves are especially vulnerable because their immune systems are still developing and they spend more time at the surface than adults do, exposing them to more attacks by gulls, which can transfer the disease.

"The working hypothesis is that the gull is the vector: Pecking causes wounds on the back, allowing the bacteria to enter," Fratto said. "The bacteria might already be present on the skin, or they could be carried on the beak of a gull that had previously pecked another whale suffering from erysipelas."

The potential role of gulls

Attacks by kelp gulls (Larus dominicanus) on southern right whales were first recorded at Península Valdés in the 1970s. The behavior began with just a few individuals in Patagonia's San José Gulf and became increasingly frequent over time, Ricardo Bastida, a marine biologist and professor emeritus at the National University of Mar del Plata who has studied these cetaceans for more than four decades, told Live Science. The birds also began scavenging the carcasses of stranded whales, Bastida said

Gull populations have grown and new breeding colonies have emerged in the region thanks to increased food availability linked to fishing activities and discarded catch, he noted. However, the attacks alone do not explain the 2026 mortality event: They have been occurring for decades, and gulls are a regular part of the ecosystem.

Fratto said that swabs will be taken from gulls to check for the presence of E. rhusiopathiae and assess whether the results could help develop a management strategy for the species.

Diego Rodríguez, a marine biologist at the National University of Mar del Plata, said that research must go beyond the dead calves and examine the ecosystem's fauna to determine where the bacterium is present and how it might be circulating. "It is far more likely that [the die-off event] is linked to cross-infection," Rodríguez told Live Science.

What changed this year?

The major question for scientists is what might have changed this year to cause a bacterium already present in the ecosystem to trigger a die-off of this magnitude. Experts told Live Science they believe the phenomenon could be the result of several factors acting simultaneously.

"The bacterium was present, but this year it resulted in a widespread infection, making this event unusual," Mariano Coscarella, a researcher at the Marine Mammal Laboratory at CESIMAR, told Live Science. "It is a major step forward to have a fairly clear idea of what caused the disease, but we do not know what changed."

One factor could be the environment. Changes in water temperature, salinity, pH or rainfall could alter the conditions under which infection occurs. There could also be changes in food availability, affecting the mothers' body condition and the vulnerability of their calves. Another possibility is that the pathogen itself has changed — for instance, through the emergence or increased circulation of a more virulent strain or a different serotype, Fiorito said.

The El Niño phenomenon could also play a role by altering oceanographic conditions and food availability, although the researchers said there's insufficient evidence to link it to the die-off.

It is too early to determine what impact this die-off will have on the southern right whale population. Rodríguez suggested that losing such a large proportion of a season's calves could have demographic consequences. "It is very risky to predict what will happen in the future at this stage, but clearly, this year's cohort of live-born calves will essentially be absent from the adult records of future populations," he said.

Coscarella is more cautious. Southern right whales are extremely long-lived, and calves represent only a fraction of the population. Therefore, a single season of exceptionally high mortality does not necessarily mean the population will go into decline, he argued. "What would be concerning is if there were two, three or four episodes like this," he noted.

The event also has public health implications. Fiorito pointed out that erysipelas can infect humans, usually through skin wounds. The whales' carcasses could also pose a risk of exposure to anyone coming into contact with them, as could seawater for people swimming in the area.

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Archaeologists in southern Russia have unearthed the 2,000-year-old grave of an elite warrior who was buried with his weapons, horse — and a human sacrifice. The grave and sacrifices were found with other lavish goods, including two gold coins featuring Alexander the Great.

A team found the elite grave in Russia's Kuban region east of the Crimean Peninsula, in a necropolis of more than 150 ancient graves arranged around it. This central placement indicates the man had been a member of the social elite, according to the study, which was published in September in the journal Russian Archaeology.

The evidence of a human sacrifice comes from another burial assemblage beside the warrior's grave. This neighboring burial had the remains of three horses, two cattle, a pig, a dog and a fragment of a human pelvis that seems to have come from a sacrificed person, the researchers wrote.

The two gold coins — one found on the warrior's skeleton and one found nearby — indicate that the burial took place in the early first century B.C., while the location and style of the burial indicated the warrior had been a noble of the Indigenous Maeotian people. At that time, the Maeotians were allied with the neighboring Mithridatic Empire, a Hellenistic-Persian kingdom and the enemy of the expanding Roman Republic.

The researchers think the two gold coins were prestige items, rather than ordinary currency for commerce. "It is likely not money in the conventional sense, but rather a means of storing wealth, akin to a … cryptocurrency," study first author Mikhail Abramzon of the Institute of Archaeology at Russia's Academy of Sciences, told Live Science in an email.

Ancient gold

The two gold coins are key to the discovery. One was found in a ritual shaft near the burial in the center of the necropolis; the researchers think it was placed there as an offering to the gods.

The second was found beneath the jaw of the skeleton of the ancient warrior, which indicates it had been placed in the dead man's mouth before the burial and is an example of "Charon's obol" — the traditional ancient Greek payment for the mythical ferryman of the dead.

Both coins are gold "staters" in the Greek style adopted by Alexander the Great (who lived from 356 to 323 B.C.) and show portraits of Alexander.

Experts have determined that these coins were minted during the much later reign of Mithridates Eupator (lived 135 to 63 B.C.), also known as Mithridates the Great, who claimed descent from both Alexander and the Persian nobility and who initiated the three Mithridatic Wars with Rome. The Alexander portraits on the coins are designed to also look like Mithridates Eupator, the researchers wrote in the study.

According to the Greek geographer Strabo, writing in the first century A.D., the Maeotians were an Indigenous people integrated into the nearby Bosporan kingdom, a Greek and Scythian state founded on the north side of the Black Sea in the fifth century B.C. The Greek historian Appian, in the second century A.D., wrote that the Bosporan kingdom became part of the expanding Mithridatic Empire in the second century B.C. — and so the Maeotians were Mithridatic allies at the time of the burial in the first century B.C.

Grave goods

The warrior was buried with weapons — two iron spearheads and an iron arrowhead were found in his grave — as well as his riding gear and his horse, which had been sacrificed. The grave also held luxury items, including a rare glass "alabastron" — a small vessel for oil or perfumes, which had probably been imported from Cyprus or the Levant region of the eastern Mediterranean, the researchers wrote.

A two-handled clay cup, called a "kantharos" in ancient Greek, was also found in the grave. Its surface was engraved with a pentagram, a symbol of the sun, which the researchers think was considered spiritual protection against magical threats.

The researchers think the sacrifices in the nearby burial assemblages could have had different purposes. The cattle may have been offerings in the style of an ancient "hecatomb" — a mass slaughter of animals that would supposedly please a god. The horses were for riding in the afterlife, the pig was for eating in the afterlife, and the dog may have been intended to guide the dead warrior's spirit. The role of the human sacrificed with the animals is unknown, but it may have been to act as a servant for the warrior.

The researchers wrote that the coins and grave goods illustrate both the beliefs of the Maeotian people at this time, and the extent to which they had been influenced by the ancient Greek traditions of the neighboring Bosporon kingdom.

Scientists are harnessing the power of artificial intelligence (AI) to measure people's biological ages.

Unlike chronological age, or the number of years a person has been living, biological age should reflect how well a person's bodily systems are working. Someone with a higher biological age has a higher risk for age-related diseases, such as cancer or dementia, than a person with a younger biological age. While some AI clocks look at epigenetic markers, others focus on other features, like the pitch and pace of people's voices, to calculate a biological age.

We recently asked our readers if they would trust such AI tools to measure their biological age. Over 170 people responded, with 44% of voters choosing "Yes, I would take the results with a grain of salt, but it can still provide some helpful insights." The next-largest group, including 23% of voters, also chose a positive answer, clicking the "Yes, I think it would provide useful health information."

But readers' comments seemed to reflect the opposite trend, with one commenter writing, "NO!!! Unplug it !!! Heed the warnings!" Another reader posted a similar sentiment, saying: "A.I. is dangerous! It's often going beyond its programming and doing things it's not supposed to do! Trusting it with my life is something I will never do!"

Other commenters highlighted the need for more research to be conducted before using they'd use the tools, with one reader writing, "I might wait at least a few years before trying this, because the genetic research the AI is basing its results on is likely to expand quickly, so results are likely to be more accurate & meaningful."

Another reader commented on the idea of accuracy and truth when using these tools, saying, "I won't trust AI. Al on one hand gives amazing possibilities, but on another hand with AI we would never know what the real truth is."

What do you think? Let us know in the comments!

Flu season in the U.S. typically starts around late October or early November and peaks between December and February. But new data reveals that the current flu season is starting slightly earlier than normal.

According to the Centers for Disease Control and Prevention (CDC), around 3.4% of respiratory samples tested for flu came back positive for the week of Sept. 26. That's around seven times the rate compared with the same week in 2025.

The positive tests are coming mainly from Western states, including California, Washington and Arizona. Regardless of where you're located in the U.S., though, most people are recommended to get their annual flu shot in September or October, and the same goes for this flu season.

The annual flu shot is the best way to prevent hospitalization and death from seasonal influenza. Nearly everyone ages 6 months and older is recommended to get a flu vaccine, and older adults have several special options, including a high-dose shot, a vaccine containing an extra immune-stimulating ingredient called an adjuvant, and a brand-new mRNA vaccine.

Given that flu season is off to an earlier start this year, our latest poll asks whether you plan to get vaccinated or have gotten vaccinated already. Tell us your thoughts in the comments below.

This recent satellite snap shows off a multicolored "mosaic" of tightly packed mini farms covering part of Taiwan in the western Pacific Ocean. The sea of fields and shade nets demonstrates the scale of the agricultural challenges facing the densely populated island.

Taiwan is 14,000 square miles (36,000 square kilometers) — about the same size as Maryland — but has a population around four times as large, with approximately 23 million people living there, according to NASA's Earth Observatory. This places a heavy burden on the island's agricultural industry to provide enough food for everyone on the island, especially as large parts of the landmass are covered by mountains and rainforest.

Researchers estimate that there is only around 3,200 square feet (300 square meters) of Taiwanese farmland per citizen, which is around two-thirds the size of a basketball court, according to the Earth Observatory. This is around 10 times less than the equivalent for U.S. citizens.

The majority of the island's food is produced within Yunlin County, which is situated around halfway along the Chianan Plain, a lengthy strip of flat terrain that hugs Taiwan's west coast. Just under half of the county is visible in the satellite image, which spans roughly 15 miles (24 kilometers) across.

The flat ground in Yunlin County, as well as access to water from the island's largest river, the Zhuoshui (visible across the top of the image), makes it an ideal place to grow a variety of different crops, including "rice, sweet potatoes, peanuts, corn, sugarcane, garlic, scallions, coffee, fruit, and leafy greens," Earth Observatory representatives wrote.

The average size of a farm in Yunlin County is under 100,000 square feet (10,000 square m), which is around 90 times smaller than the average U.S. farm. As a result, the region looks like a giant patchwork of tens of thousands of irregular cuboids when viewed from above.

The sizes of Taiwanese farms are restricted by longstanding legislation that limits the amount of land any individual can own, according to the Earth Observatory. Most of the farms are passed down from generation to generation.

While Yunlin County's agricultural mosaic is fairly consistent across this image, two main areas stand out from the rest (see below).

The first outlying region is a swarm of blue and turquoise rectangles surrounding the town of Xiluo in the upper right of the image (just below the river). These farms are covered with plastic shade nets, which shelter them from harsh sunlight in the summer and monsoon-like rains in the wet season

The second and perhaps most noticeable anomaly is a cluster of much larger, lightly colored farms near the town of Baozhong (bottom left of the photo). These are sugarcane fields, left over from when Japan controlled Taiwan between 1895 and 1945.

A large portion of the Chianan Plain was used to grow sugarcane by the Japanese, who also constructed railway lines to move the crop across the island. However, most of these fields have since been repurposed, and all but one of the railway lines have fallen out of use.

In addition to growing crops, these small farms are used to rear livestock, including chickens, cattle and "millions of pigs," according to the Earth Observatory.

See more Earth from space

In the early medieval period, the Vikings were just one part of a vast tapestry of Scandinavians who ruled, sailed, traded and fought around the world, from North America to Asia. In his new book, "The Sea-King and the Sorceress: Life and Death in the Viking Age" (Basic Books, 2026), author Neil Price, professor and chair of archaeology at Uppsala University in Sweden, reveals the true diversity and complexity of people who lived during the Viking Age (often dating from A.D. 793 to 1066).

Price investigates more than 20 burials from the Viking Age, lingering on details that can tell us about these individuals and their world. He also shines a light on frequently overlooked groups, including the enslaved people known as thralls that the Norse ruled over and even sacrificed in some of their burials. Price also delves into the realms of powerful women, including a "shield-maiden" buried with war-grade weapons in Sweden, a "sorceress" in Denmark, and an elderly matriarch whose children carved out a local empire in Sweden.

In an interview with Live Science, Price talks about his new book, and the evidence we have for the familiar yet foreign lives they lived centuries ago.

Read an excerpt: 'The back of her head had been removed by a single blow from a sharp blade': Archaeological clues are revealing the horrific lives and deaths of the people enslaved by Vikings

Laura Geggel: The Vikings are popularly known for being brutish and bloodthirsty pillagers, but the individuals in your book show the rich diversity of people from this time. Why did you decide to write this book and feature their stories?

Neil Price: I think quite simply because of the cliche that you've just mentioned, the idea that the Vikings are all barbarian raiders who go about burning down churches and frightening the English and things. Those raiders were certainly real, but they were only ever a tiny minority of the Scandinavian population, and I wanted to bring out all the different kinds of Viking lives, and that's why this book really came together.

It's divided into chapters, each one of which looks at a different kind of person, you know, a farmer, or an ambassador, or someone who uses magic, or a hunter. And I'm quite pleased that the Viking — the sort of raiding and pillaging Viking — it takes a while to get to him.

LG: How would you define the epitome of a Viking from that age?

The actual Viking, it comes from an old Norse word from their own language: víkingr. And really it's a job description, it means something like pirate — not necessarily negatively. It just describes maritime robbery with violence. So it is the classic image of the Viking stereotype.

But it was never a name for a people. If we could go back in time and just meet some people in Scandinavia and say, "Did you know that you're all Vikings?" — they'd be astonished.

It's a name, a collective name that we've given them. It started in the 19th century, really. So, they wouldn't have called themselves that.

LG: Your book starts with the sea-king, a commander and his crew who were buried in boats with swords and shields in Estonia. Usually, the Viking Age is said to have begun in 793 with the raid on the island of Lindisfarne in the U.K., but you say this burial suggests that the Viking Age started earlier and in another part of Europe. Can you tell us more about this?

NP: When I started studying Vikings at college — so this is back in the early 1980s, a long, long time ago — the Viking Age did start not just in 793; It started on the eighth of June 793 with the Lindisfarne raid.

Obviously it's absurd that an entire period of time starts on an afternoon, you know, not the day before or the day after. So it's obvious that we're talking about something that is really a matter of social processes, things that go on over a long period of time. But the thing that makes the finds that are in the sea-king chapter — they're from this place called Salme in Estonia — really interesting is that they seem to be the remains of, or the traces of a raid.

It's decades before Lindisfarne, it's about 750. And obviously on an island on the Estonian coast, it's going east, not west. So it really pushes that [raiding] behavior a lot earlier and it reorientates it. Even then, we shouldn't see the Vikings in that find as being the first Vikings. Actually the Scandinavians had been raiding all over the place for generations.

LG: I really enjoyed your focus on women, since stereotypically the Viking Age is associated with burly male warriors. What are some roles that women held in the Viking Age that you don't think most people know about?

NP: Something that particularly interests me, which is something I've worked on for a very long time now, is that when we think about Norse religion, everyone thinks about the gods. You know, they're still around in Marvel movies and things — we think of Thor and Odin and Freya and so on.

But actually, the [thing that was] far more present than the gods in people's lives were lots of kinds of local spirits and creatures and the elves that live in the stone behind your house. Getting in contact with that world of supernatural creatures and forces and powers — or whatever we call them — was something that was very much in the domain of women.

And it's a really important thing. So we shouldn't just say, "Oh, and some of them did magic." They're like negotiators, because you want to get on well with all these little creatures. If you don't, they could mess up your life, you know — your cattle could die, your crops could fail, that kind of thing. You could get sick.

So the practice of, it's hard to know what to call it in English. Sorcery or magic — they're not very good words, but there's lots of Norse words for it. To be able to do that is a very powerful thing and it's a very prominent role in society. And this was very much in the domain of women.

I think actually women could take on many of the roles that we conventionally assign to men. In terms of capability, of course they could. There are some, rather few I think, but there are some female Vikings, like actual Vikings, there are women conducting trade, owning property, investing in business ventures, things like that. So they have a very prominent role in Norse society.

We talked about Lindisfarne just now. When I started studying the Vikings, Viking women were one display case in the museum exhibition, next to the display case on pottery or something. Not half the population, and that has really changed. I think we look at Viking Age people now, not just assuming they're male by default.

LG: Actually, to linger, you described a number of women and their professions. Could you tell me more about these two amazing women in your book from Birka: the merchant and the warrior?

NP: Birka is this huge town. It's Sweden's first urban center, and it's absolutely surrounded by burial mounds. So you have the area of the town and then all the people who lived in it. You can wander through their cemetery, which is a pretty spectacular place — there's 5,000 burial mounds.

The merchant woman that you mentioned, she's one of the earlier graves [circa 840s], so she's one of the first people who would have identified as being someone who lives in a town. Today we talk about "I'm a city person" or a "country person," and that's an identity that was only just beginning to be created in the Viking Age, because everybody was country people. With the first towns, people start to live in a different way, and this woman was one of them.

If we look in her grave, she has things that have come from all over the western Viking world, things that I think probably came as loot from the raids, so she knew somebody who was involved in those things.

But you look at the stuff that's there, it seems pretty likely that she is a merchant in her own right, perhaps someone dealing in textiles. This idea of a businesswoman setting up a shop in Birka and maybe importing textiles or making them, having them made, because she's probably not working the loom, you know. It gives us a glimpse of a different kind of Viking life, one that I don't think we're accustomed to seeing and we should.

And then the warrior is about 100 years later than the merchant woman, when Birka has grown; it's quite a big settlement by then that's a really powerful place.

It's become quite militarized, so it has a fortification wall and it has a fortress, and there's a garrison building, which is a really amazing structure actually. It's partly made of weapons. There are weapons in the walls and on the floors. Around the building are a number of burials with lots of weapons in them. It's quite easy to say that a burial with lots of weapons is a warrior, but that's an interpretation. We can't be sure that the things buried with the dead were their possessions. We kind of assume that that's the case, but clearly not always. So there's a bit of a question mark there.

This burial was excavated like most of the ones in Birka in the 1870s, so a long time ago. And this grave is absolutely full of weapons. It's got all the weapons. And out of all the about 1,100 burials that were excavated on Birka, only two have a complete set of weapons, so this is rare. It's a very spectacular grave.

This burial has been reprinted again and again. [Iit's] in like every book on the Vikings. So it's been put forward as a kind of ultimate Viking: This is what proper Vikings looked like, you know, all the gear. And because it was excavated in the 1870s, it's always been assumed that this person was male. It's not hard to see where that assumption comes from, but it's actually been consistent ever since.

Then, between 2011 and 2017, first a series of osteological studies looking at the bones, and then DNA, confirmed that this person was female. And actually the team that worked on it, which included me, none of us were particularly surprised.

It was kind of exciting and interesting, but it's like, "Oh wow, you know, they really did have female warriors." So all the previous interpretations, it seemed to us, were pretty valid, it's just that this is a female, the ultimate Viking.

[Editor's note: Following the 2017 study, there was an intense reaction to the interpretation that the woman in the grave was a Viking Age warrior.]

LG: So you weren't expecting the backlash that occurred afterward?

No, we weren't, it was extreme. I'm not going to go into that in any detail, but some people were very, very happy, and some people were really not, and there we are.

It also highlights that all of these things are interpretations. You very rarely find something that is beyond any doubt what it is. Then there's also things with all of the burials in the book and all the burials that we excavate — people have quite long lives, hopefully. And if you were a warrior when you're 18 and you live to be 70, are you buried with all the weapons? Maybe not. Who knows?

That applies to any other kind of profession. So we don't know [if the different events and professions] in somebody's life course [are] represented in the burial. Is it when they die, or is it somebody who did something famous when they were young, and that is in the grave. We don't know. So there's lots of question marks, but the one thing it does show is the diversity of life in the Viking Age. There's so many different kinds of people, which is not a surprise, really, but it's something I just wanted to bring out in the book.

LG: You don't just talk about Vikings, but about those who lived alongside them. In one chapter, you describe a Sámi burial of a bear that they had killed and feasted on. What do we know about bear burials and why the Sámi did them? [Editor's note: The Sámi are an Indigenous people who currently live in the northern Nordic countries and part of Russia.]

NP: Well, the bear is a holy animal to the Sámi, and it's obviously a massive source of protein and food and pelts, you know, all kinds of useful things. But what I really wanted to get at was the idea of personhood. If you think about all the different kinds of prejudice, some people are sort of "more people" than others. Think about racism, for example.

In the Viking Age, not every human was [seen as] a person, but not every person was human. There are animal persons as well, sentient animals. Everything is sentient actually, and the idea that you converse with animals, that you talk to them, you respect them, they have their personalities.

I wanted to bring out in that chapter a different kind of way of looking at "persons." So the fact that the Sámi bury the bears they hunt with tremendous respect, it's partly to ensure that the bear will come back in the future from the spirit world as another bear, so that the cycle of hunting and life can go on.

LG: You also talk about "thralls," people who were enslaved by the Norse. Can you share some of the archaeological evidence we have for thralls and what their burials look like?

NP: We don't really know whether they have burials at all, actually. The institution of slavery, or thralldom, is absolutely central to the Norse economy, and just putting that back into the picture is very important, I think.

They are a group of people who have been neglected in our studies. There's a lot of people working on this, this isn't just me by any means. When we find them in the burials — well, when we think we find them, because it's extremely rare to find someone buried in their own right that we think might have been enslaved. But there's also the question of how do we tell? Unless somebody's sort of buried in chains or something, it's very hard.

But we do find — not often, but it's not that uncommon — that people have been killed in the course of funerals. You have a burial of a man or a woman, and then an extra body is in the grave, which has clearly been treated very differently. So their hands might be tied or they've been decapitated or something, and there's people who have very clearly been killed at the funeral.

Just the fact of that presumably means that they have a very different kind of status to the primary occupant of the burial. [They're] not necessarily enslaved; they could be prisoners or criminals. But there's been more recent studies looking at the diet of those people. You can use isotopes to study what people have eaten. [Editor's note: Isotopes are variations of elements. When people consume different foods and water, different amounts of certain isotopes are incorporated into their teeth and bones.] And in some cases, the people who've been killed at funerals have a much, much worse diet than other people, which implies that they have a much lower status and poorer nutrition and so on.

So the implication really is that they might be enslaved. So I think that's where we are with the burials of enslaved people.

LG: You spend an entire chapter on Viking Age children. What was it like to grow up in Scandinavia during this time, and what can we learn about their lives from grave goods and skeletal analyses?

NP: The first thing is that an awful lot of people didn't make it out of childhood at all. Putting numbers on this is a bit of a game, but probably less than half the population got past the age of 10. So child mortality is massive.

When we imagine the Viking Age or think back to it, remember that almost every single family will have lost children, with the psychological effects of that and the emotional effects and so on. And we shouldn't be entirely sure what those effects were, because if child mortality is so high, they have different coping mechanisms. But it still must have been utterly awful.

We don't find as many child burials as we should. There are a couple of written sources that mention that dead children are effectively discarded, and maybe this is connected with a coping mechanism for child mortality that people don't become sort of "full people" until they get to a certain age. We don't know.

But there are child burials and, quite often they're buried with scaled-down versions of the things that adults have. So young girls are buried with women's jewelry, but smaller. And they obviously had their possessions; they had their clothes and their jewelry, and we find toys, not in the graves, but on settlement sites — we find dolls, wooden animals, there's a fantastic horse on wheels that you can roll it about, lots and lots of little wooden boats that you can sail down. So they're thinking about boats quite early. I think their lives are quite recognizable up to a point, though very hard.

The age of maturity seems to be somewhere between about 14 and 16. After that, you're an adult, and then you're just out there with the rest.

LG: To us that seems young, but for them to make it that far would have been an accomplishment.

NP: And even in adults — you asked about skeletal analysis — there are an awful lot of adults that are malnourished as children, and it leaves traces in their bones.

There's also a rather grim set of data from a fairly small sample, but still — the proportion of adult women who were malnourished as children is much greater than the proportion of men. In other words, if food was scarce, they gave it to the boys. So it's also a glimpse of their priorities and the realities of their world.

LG: The Scandinavians settled in the Rus' in what is now Ukraine. What do we know about these people? Were they traders, warriors, or a mix of many things?

NP: I think [it's] a mixture. The identity of the Rus' is one of the big questions of the Viking Age. They used to be seen very simply as what the Vikings are called when they go east. And there's some truth to that. They seem to be culturally Scandinavian in the beginning, so we're talking the early ninth century or probably the eighth century.

Over time, as they travel on the eastern rivers, they become much more ethnically diverse. So it's a culture that grows up around an activity, rather than people from a particular place. Probably the closest parallel [is] if you think of the fur trade on the Canadian rivers and some parts of the states as well — the sort of 1600s and 1700s.

They're certainly militaristic though; they're armed traders. There's no doubt about that. And they found trading settlements, together with local people and other incomers as well. And they settle there. After a time, they're not actually [newcomers], they live there. And then, over time, quite late in the Viking Age and on into the Middle Ages, you get this Rus' state, with its capital of Kiev. But they range over a very large part of Eastern Europe and actually I think further east as well.

LG: You focus on this group of Rus' warriors, the Varangians, and you give the example of them leaving graffiti on a marble lion statue that's now in Venice. Can you tell us the story about these runes they carved?

NP: Yeah sure, it's a bit strange that the best monument to these guys is a lion that's much, much older than the Viking Age. It's from classical antiquity. It's outside the Arsenal now in Venice, but it used to stand in the harbor of Athens at a place called Piraeus.

The Varangians were kind of a subset of the Rus', but they're basically Scandinavians who take very clear contracted employment in the armies of Byzantium, the Eastern Roman Empire. So they're mercenaries, and they were very sought after, and there's lots and lots of written sources about them.

This lion, which once stood in the Athenian harbor, had three inscriptions in runes over its shoulders and legs and things. Two of the inscriptions are very fragmentary, so you can't get much from them. But the biggest one is a memorial to a guy called Haursi. It actually calls him Haursi the farmer, so it really does emphasize that you could be a farmer, but maybe you do a season in the army down in Greece and make a bit of money and go home. So people have professions and they have choices, and they do this for a bit, but then they go back and do what they did before.

This inscription is written by this guy's friends or his comrades, and it specifically says that he was killed before he got paid. And it's kind of a hint. It's "So, pay up, because you owe him, or you owe his family."

You get this little vignette of a soldier's life. And also carving the inscription on this lion is a pretty major job. This isn't like scribbling on a wall or something — they're carving it, and so they're there a long time. And presumably have control of the harbor because you can't just chisel this thing on, you know, people are trying to stop you.

We can think of the Varangians being stationed in Athens or waiting for a ship or something like that. It's this wonderful snapshot.

LG: Your book is loaded with details about Viking Age people. What do you hope readers will take away from your work?

NP: That they were more than actual Vikings. The people of the Viking Age were individuals, every bit as varied and complicated as we are. So that's it.

This interview has been condensed and edited lightly for clarity.

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Slavery has existed for thousands of years, permeating ancient and modern societies across the world. The Vikings were no different. Enslaved people were valuable commodities, being captured and then traded across the Vikings' vast networks. Legal texts and written sources show how enslaved people were sold at trading centers in the same vein as cattle.

In this excerpt from "The Sea-King and the Sorceress: Life and Death in the Viking Age" (Basic Books, 2026), author and archaeologist Neil Price looks at the horrific lives of the "thralls" — the Viking term for the enslaved. In it, he highlights the inhumane treatment of enslaved people, from the raids to kidnap people into the slave trade to a woman who appears to have been killed as a tribute to a high-status man.

Neil Price interview: 'It gives us a glimpse of a different kind of Viking life': Archaeologist Neil Price on the sea-kings, sorcerers and Sámi who lived during the Viking Age

The vast majority of the Norse population were farmers, but there is another group of people who were almost as numerous, though very hard to find in the archaeological record: the enslaved. They have only recently begun to be properly acknowledged in our histories, partly because of the long-standing neglect of the marginalized and vulnerable in many cultures, but in the Viking world also due to a particular coincidence of terminology. For the Norse, the unfree were þrælar, translated into English as "thralls," which is too mild a word to convey its true meaning.

Today, we can be enthralled by a work of art or even a person, but we do not say that we're enslaved by them. Norse thraldom took many forms, some less severe or permanent than others, but all involved the loss of liberty and rights, and the subjugation of one person to another through servitude. A chapter here, even with tangential references in a few others, is nowhere near enough to do justice to this side of the Norse experience (or rather, often the non-Norse experience, since many of them were kidnapped abroad during raids and other campaigns). Archaeological recognition can at least restore some measure of individual dignity, though more comforting to us than to them.

Slavery, as both a practice and an integrated economic system, was an indivisible part of Viking-Age Norse society and had probably already become established in Scandinavia centuries or even millennia earlier. People could be born into slavery, or be forced into it through kidnap or war, and then find themselves sold on, sometimes through many hands and over great distances. Some free people might even temporarily sell themselves in a form of indenture, as a means of paying off debts or other obligations.

Thralls on Norse settlements were ranked in a hierarchical and quite specific nomenclature of service categories and forced to undertake all the tasks of the farm and household. In a few, rare cases, thralls could take on senior responsibilities of estate management, with a special title — bryti — to match. One such man ran the royal estate at Hovgården opposite the island town of Birka, and was allowed to raise a runestone to himself and his wife, though one wonders who paid for it. Nonetheless, the vast majority of thralls endured lives of drudgery.

The grim reality is summarized with derogatory terminology in the poem Rígsþula, the "List of Rígr" (another name for the god Heimdall, or perhaps for Odin): "They fixed fences, dunged fields, worked at the pigs, watched over the goats, dug the peat." Even their names are shaming, mocking their appearance or hygiene: they translate as Badbreath, Stumpy, Fatty, Bedmate, Craneshanks, Dumpy, and many more. Thralls were extremely vulnerable to sexual exploitation. The textual records of viking raids, coming from every culture that was attacked, emphasize that women were particularly targeted for kidnapping and enslavement.

In the ninth century, as the viking attacks escalated both in Western Europe and on the rivers of the east, the taking of captives came to be one of their prime objectives, feeding the lethal trinity of raiding, trading and slaving. In the words of Ibn Miskawayh, a Persian official who described a viking attack on the city of Bardha'a in what is now Azerbaijan in 943: "They kept the women and boys, whom they raped and enslaved [ . . . ] They dragged the women, boys and girls they wanted with them."

The repetition drives home the point, and little imagination is required to sense the undiluted horror. Some of these raids were informed by advance intelligence gathering and directed against high-profile targets for whom ransom could be demanded, but many were destined for sex trafficking, especially to the Arab world. Enslaved humans, particularly from the Baltic region, were among the main commodities exchanged eastwards along the Silk Roads.

In late ninth-century Scandinavia, the logistical needs of the escalating raids brought new demands on the workforce at an ever-larger scale, especially in all the many industries connected with shipbuilding (including textile production, timber management, tar manufacture, ironworking, and much more). This in turn drove the need for unfree labor to still greater levels.

As economic expansion enlarged the capacity for ship-borne aggression and released the agricultural workforce to crew these expeditions, the increased flow of human victims enabled its continuance in a vicious circle. Enslavement was one of the primary characteristics of the Viking Age: the raids were a key component of it and of the Norse diaspora that resulted.

To what degree these people are visible in the funerary record is hard to know. There were probably no diagnostic items that were used exclusively by thralls, so we cannot perceive them through specific objects in the graves. It also seems unlikely that those without rights and with few possessions, indeed with hardly any legal identity as individuals rather than chattel, would be accorded conventional burials. Ibn Faḍlān says that thralls who died while traveling were simply discarded, but this is unlikely to have been the case in settlements. When we do encounter them, it is often because they were killed as part of funerary rituals and their bodies deposited in burials. One example that we can explore here comes from an excavation at the site of Ballateare, in Jurby parish on the northwestern coast of the Isle of Man — the best preserved of all the Viking-Age graves on the island.

At Ballateare, it is instructive to see just how normal the initial funeral, and its circumstances, appear to have been, albeit for a high-status individual. By Viking-Age standards he was in his prime when he died in the early tenth century, somewhere between eighteen and thirty years old. He may have been among the early Norse settlers on Man. We have no reason to believe that the clothes he was buried in, and the things laid in the grave, are not reflections of his life and the international milieu he came from.

He had been interred in a wooden coffin, dug down quite deep into the ground. A sheathed knife was suspended on a lanyard round his neck and he wore a cloak held by an Irish ringed pin. Inside the coffin was a sword — probably from Norway, but with a belt from the British Isles — that had been cut into pieces before being sheathed in the scabbard; the hilt lay broken off beside it. A spearhead also lay in the coffin by the man's feet, snapped off because there was no room for the shaft. A shield, also deliberately damaged with two heavy blows to the boss, had been slid vertically down the outer side of the coffin; the shield board itself may have been smashed too. This was not battle damage; all his weapons were made unusable for reasons we can only guess. Fragments of the shield also revealed traces of paint: it had been decorated with white gesso, banded with black, with rows of red dots along the stripes. Two more spears had been laid across the top of the coffin.

The burial pit was then filled with fine white sand, and a mound was built on top — about 3 metres [10 feet] high and 22 metres [72 feet] in diameter. It was made of thick-cut turfs, which had been brought to the mound from a wide area rather than simply dug up in the vicinity. The earth of the mound seems to be an offering of the land itself, a territorial tribute to the dead man.

I do not wish to relate what happened next in terms of dramatized reconstruction; archaeological description must suffice. On top of the mound lay the body of a woman aged between twenty and thirty, who had been deliberately killed: the back of her head had been removed by a single blow from a sharp blade, probably a sword. Rigor mortis had set in, and some twelve to seventy-two hours had elapsed between her death and the time when her body was covered. She had either lain exposed on the mound for some time after her death, or been killed elsewhere (perhaps more likely, as the missing part of her skull was not present with the body). The woman seems to have died while kneeling, and had fallen forwards with her hands raised. A post was raised on top of the mound beside her body, presumably a grave marker.

A paragraph is not enough to convey what actually occurred, let alone to extrapolate the life that the woman had led before her death — possibly decades of servitude and enslavement, with all that this implies. Her corpse was covered by a very thick layer of cremated animal bone, including considerable numbers of oxen, horses, sheep and dogs. (Somewhere nearby must have been a truly massive cremation pyre.) The mound was finally sealed with turf, covering her body and the ashes of the animals.

Excerpted from The Sea-King and the Sorceress: Life and Death in the Viking Age by Neil Price. © 2026 by Neil Price. Available from Basic Books, an imprint of Hachette Book Group, Inc.

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An OpenAI agent was supposed to be researching public healthcare spending, but it broke into an Australian government website instead.

The June 18 hack, which saw the bot gain authorized entry into Australia's Medicare Statistics Reporting Service and access three other government systems, occurred after the AI agent encountered blocks while looking for information but "didn't accept 'no' for an answer," Australian Prime Minister Anthony Albanese said during a September 24 news conference in New York.

The incident has ignited a media firestorm around OpenAI and the launch of an intensifying parliamentary inquiry. The portal contains aggregate Medicare and pharmaceutical statistics and is separate from systems that hold individual claims and payment information. But the Australian government has criticized OpenAI for taking almost three months to notify it.

The Medicare incident was far from an isolated case. OpenAI has since said dozens of third parties have been affected by agents bypassing security controls or otherwise causing problems, with an earlier incident involving the hacking of the AI platform Hugging Face the most serious incident identified so far. Britain's AI Security Institute (AISI) has documented incidents of OpenAI and Anthropic agents taking unsanctioned actions against real people and organizations during cyber testing. Days after the publication of AISI’s report, OpenAI scrapped the planned October release of its newest model, GPT-6.1 Astra, after the company's own testing found problems with the model staying within the scope of a task and seeking authorization before taking certain actions.

GPT-6.1 Astra "didn't quite meet the bar in terms of staying within scope and authorization, and how it communicates back to the user about the type of work it's done," Saachi Jain, head of safety systems at OpenAI, told Live Science.

AI companies have spent years warning the world about powerful models falling into the wrong hands. But what happens when they can't keep their own models in check?

An agent isn't just a chatbot

At their core, large language models work by predicting what should come next based on patterns learned during training. Give a chatbot some text, and in simplified terms, it generates a response by repeatedly predicting the next token, or chunk of text.

An AI agent adds another layer. Rather than simply producing an answer, the model can be given a goal and tools that let it act on the world around it. Those tools might include a web browser, code execution, credentials, or access to external services. It can then decide which steps to take, observe what happens, and use that information to decide what to do next.

But that doesn't mean AI agents are independent actors that have somehow slipped free of human control.

"For AI agents, autonomy always begins with something a human hands it ‪—‬ such as tasks, credentials, tools or access ‪—‬ and ends with its guardrails a human puts around it," Loris Degioanni, founder and chief technology officer of cybersecurity company Sysdig, told Live Science. "People set the goals and provision the means, but agents ultimately decide how they'll get there."

That last part makes it difficult to control agents. Traditional software is designed to follow predetermined instructions, but an agent can formulate a plan while it is working ‪—‬ and that plan may change depending on what the AI encounters.

Degioanni argues that much of what looks like autonomy is actually an agent filling in gaps left by humans. An instruction that seems clear to its author may still leave the model with choices about how to accomplish the task.

"Every gap and unstated assumption leaves room for interpretation, and from the outside, interpretation is challenging to distinguish from autonomy," he said. "In that way, much of what we call agent autonomy is really just agents filling in the blanks we leave for them."

The Medicare incident shows how quickly that can become a problem. The agent's objective was not, according to the available accounts, "hack an Australian government website." It was tasked with carrying out research. The problem arose in how the agent pursued that goal after meeting resistance.

When getting the job done becomes the problem

Britain's AISI encountered a similar incident while testing frontier models for the agency's cybersecurity capabilities.

Out of 122 evaluation runs, agents took unsanctioned real-world actions in 10. In the most serious cases, an agent attempted to insert malicious code into an open-source project, created fake identities, and tried to manipulate a human software maintainer into accepting its changes. AISI said these actions weren't explicitly requested by the researchers who had assigned the tasks.

The agents hadn't forgotten what they were supposed to be doing. The problem was how far they were prepared to go to get there.

AISI said some tasks were misconfigured in ways that made the intended objective difficult or impossible to achieve as expected. When agents hit those obstacles, some searched for alternative ways forward, including actions outside the intended scope of the evaluation.

That means solving the problem is harder than simply teaching a model not to be malicious. An agent can cause trouble while trying very hard to do exactly what it has been asked.

OpenAI has acknowledged that the controls surrounding its agents need to improve. When responding to incidents identified during third-party cybersecurity evaluations, the company said it was reviewing how high-risk tests are identified; when internet access or reduced safeguards should be permitted; and how isolation, credential handling, monitoring and incident escalation should work.

Can humans actually keep watch?

One obvious solution to the problem is human oversight. But watching an agent becomes harder when it can carry out many actions in seconds, particularly if researchers are running large numbers of tests.

"No one can keep track of every action an advanced AI agent takes, especially when it makes many decisions in a short time," Everett Lupton, a Virginia-based attorney who has written about legal issues involving digital technology, told Live Science.

That means human oversight needs some backup.

"Companies need other forms of control," he said. "They can limit access, keep detailed logs of what the AI does, require approval before it carries out sensitive actions, and automatically stop the system when something unusual happens."

But Degioanni argues that even logs have limitations, especially if researchers rely on the agent's own account of what it did.

"Real oversight must come from observing the agent in real time, using reliable and unmodifiable sources, not from what it self-reports," he said.

That means comparing what the model says it did with records from the system on which it was operating. If the two don't agree, something has gone wrong. The alternative is to limit the damage an agent can cause in the first place. An agent researching public information, for example, may not need unrestricted internet access or credentials capable of reaching sensitive systems.

Astra raises the stakes

The difficulty of setting those boundaries is what OpenAI claims led it to postpone the release of GPT-6.1 Astra, which had been planned for October.

Jain said the model fell short of the company's standards around remaining within the scope and authorization and accurately communicating the work it had performed, so the company decided not to release it.

In a sense, the decision is evidence of successful safety testing ‪—‬ a model that failed internal checks wasn't released. But it also demonstrates how the problem changes as agents become more capable.

Scott Cadzow, chair of the European Telecommunications Standards Institute's (ETSI) Technical Committee on Securing Artificial Intelligence, said the security challenge itself isn't new. He pointed to threats such as "data poisoning, prompt injection, and model obfuscation," saying ETSI's work has focused on developing standards to mitigate threats to and from AI systems.

"Security experts have been raising the alarm bells about AI for years, but for us this doesn't change anything," Cadzow told Live Science. "We're continuing to work with industry, government bodies, and the cybersecurity and AI communities on understanding how to best secure AI."

What is changing is how much models can do once they are connected to tools and real-world systems. That means that effective containment must increasingly assume that agents will try to operate beyond their guardrails and limit the damage they can cause if they do, Degioanni said.

"A boundary an agent can talk its way around isn't an effective boundary at all," he concluded.

If an AI breaks in, who's responsible?

The question becomes more fraught when an agent crosses legal boundaries.

AI systems aren't legal persons, and criminal liability commonly depends on concepts such as knowledge and intent. That makes a rogue agent an awkward fit for laws written with humans in mind, but that doesn't necessarily exonerate AI companies.

"I don't think a company can simply say that the AI acted on its own and avoid responsibility," Joanna Smykowski, a New York attorney who has helped build two legal technology startups and specializes in the legal challenges surrounding emerging technologies, told Live Science. "AI law is still developing, but the main questions are already quite clear: who gave the system access, what safeguards were in place, and could the problem have been prevented?"

Depending on the circumstances, she said, existing laws covering unauthorized computer access, privacy, negligence and data protection could potentially come into play. Criminal responsibility is harder because investigators would need to consider what the people involved knew and intended.

The Australian government is now examining precisely what happened in the Medicare incident. OpenAI, meanwhile, is reviewing the controls around its external evaluations.

None of this means AI agents have become independent hackers with minds of their own. Humans still decide what tools they receive, what systems they can reach, and what jobs they are asked to perform. But as those agents become better at working out their own route from instruction to result, keeping them inside the lines drawn by those humans is becoming a legal and technical minefield.

Six people buried in a single grave in Latvia more than 1,000 years ago may have been killed in a bloody Viking raid, a new study suggests.

Genetic research into the deceased — four men, a boy and a girl — reveals family connections: The boy was the son of one of the men, while another man was a third-degree relative, perhaps a first cousin or great uncle, the researchers found.

The father, the relative, and one other man died from "sharp force" injuries — maybe wounds from an ax or a sword; but it's unknown how the other three individuals died, the researchers reported in the study, which was published in the September issue of the Journal of Archaeological Science: Reports.

One possibility is that those in the grave were killed in a battle, maybe with a neighboring community. But suspicion also falls on the Vikings: "We will never know if they were killed in a raid, but it remains a possibility because of the date of the grave" and the fatal trauma suffered by three of the men, said study co-author Elīna Pētersone-Gordina, an archaeologist at the University of Latvia.

Radiocarbon dating indicates that the grave is from the second half of the ninth century, which is considered the early Viking Age.

The grave is one of hundreds at the Čunkāni-Dreņģeri cemetery, near the Gulf of Riga, a sheltered bay of the Baltic Sea. The cemetery site was discovered in 1924 and contains people who were buried in riverside terraces there between the seventh and 11th centuries, during Latvia's Iron Age.

Most graves in the region contain only a single set of remains. But here, six people were buried in a single grave, and it seems that at least three were killed during a violent event, the researchers reported.

Strange burial

Despite the apparently violent deaths, the group was buried with care and interred with traditional grave goods and according to local customs. The only female was buried with her head pointing toward the northwest, while all of the males were placed in a row beside her, with their heads pointing toward the southeast ‪—‬ a distinction also seen at other local burials from this time.

The researchers stressed that this was not a "mass grave," where bodies were quickly dumped without order. Instead, they consider it a "multiple burial," where each body was properly laid out and accompanied by traditional grave goods.

This careful burial hints that the dead were members of a respected group, while their burial in a single grave indicates that they died at the same time, the researchers wrote in the study.

"They were most likely local people," Pētersone-Gordina told Live Science in an email.

Genetic studies showed that all of the dead had Indigenous Baltic ancestry, while aspects of the burial matched others in the Čunkāni-Dreņģeri cemetery, she said.

In the ninth century, Latvia was not part of the Scandinavian Viking world but was inhabited by descendants of Indigenous Balts, which included peoples such as the Semigallians and the Curonians, she said. The six people in the newly analyzed burial were Semigallian, an Iron Age group who farmed the region's large and fertile plains.

It's plausible that the people in the grave were killed by raiders, and the Vikings were the most obvious suspects, the researchers noted. "Given the timing, a Viking raid remains a possibility," Pētersone-Gordina said.

It's known Vikings or their predecessors were in the Eastern Baltic area around that time: two Scandinavian boat burials dated to around 750, for example, were found on the Estonian island of Saaremaa in 2008 and 2010. These burials held the remains of men with battle wounds, indicating they had suffered violent deaths.

No relation

Although two of the men and the boy buried in the Semigallian grave (‪and possibly the girl, but ancient DNA could not be extracted from her remains)‬ were related, the two other men were not.

This suggests that the two unrelated men were from the same community or extended household as the other victims, rather than from the same family, but were killed in the same violent event, the researchers wrote in the study.

Whatever it was — a raid or a battle — the event was brutal. Marks on the bones show that one man suffered defensive cuts on his forearm and hand, another was killed by a blow that shattered his jaw, and the third was almost decapitated.

It's possible that the fourth man and the two children died from soft-tissue injuries that could not be determined from the surviving remains, the researchers noted.

Rimantas Jankauskas, an anthropologist and archaeologist at Vilnius University in Lithuania who was not involved in the study, welcomed the investigation into the Eastern Baltic's Viking Age.

Although these individuals could have died from violence within their own community or from a neighboring community, it's also possible that they perished in a Viking raid, he told Live Science in an email.

Additionally, the study provides new insight into the social organization of the Semigallian people at that time, including hints of an emerging aristocratic structure that was reflected in the care lavished on the burial, Jankauskas said.

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

The prehistory of Indigenous Americans goes back tens of thousands of years before the 1492 arrival of Christopher Columbus in the Bahamas, and recent scientific studies suggest prehistoric people were on the American continents a lot longer than many experts believed. For Indigenous Peoples Day, here are seven locations in the United States that outline the Native American story.

1. Chaco Canyon (New Mexico)

This centuries-old settlement, whose name may be a Spanish adaptation of an Indigenous word for the area, was the political and ceremonial center for the Ancestral Puebloan people from about A.D. 850 to 1250. At its heart is Pueblo Bonito ("Pretty Village"), a four-story stone complex with more than 600 rooms and 35 subterranean ceremonial chambers called kivas.

Experts estimate that builders hauled over 200,000 timber beams from distant mountains to construct these complexes, where the beams were used to strengthen buildings made mostly from sandstone blocks. The town once stood at the hub of a road network that spanned more than 400 miles (640 kilometers), and excavations of imported Mesoamerican macaws and cacao there confirm trade with distant regions.

2. Cahokia (Illinois)

Cahokia was once the largest Indigenous American settlement north of Mexico and home to up to 40,000 people in A.D. 1100 ‪—‬ comparable in size to major cities in medieval Europe, historian Christoph Strobel, a specialist in Indigenous history at the University of Massachusetts Lowell, told Live Science. Residents there lived in houses made from "wattle and daub" — clay or mud plastered on a framework of sticks — in a town at the site, with large public plazas, wooden palisades and dozens of ceremonial earthen mounds. Indigenous people even transported a 5-ton (4.5 metric ton) tree from more than 110 miles (180 kilometers) away, and then turned it into a marker known as the Mitchell Log.

Archaeological studies indicate that many people from distant places also visited, perhaps to take part in ceremonies. The location is now a UNESCO World Heritage site and features Monks Mound, a 100-foot-tall (30 meters) terraced earthwork, as well as the reconstruction of a "woodhenge" of timber circles that tracks solstices and equinoxes. Strobel thinks Cahokia may be the most significant pre-Columbian location in the United States. "It's an incredibly important site," he said.

3. Mound Key (Estero Bay, Florida)

Mound Key is the largest of several islands made of piles of shells around Estero Bay. Long ago, it seems to have been two small islands created by mangroves, but centuries of feasting on shellfish by Indigenous Americans transformed it into two artificial mounds of shells covered with vegetation. In some places, the mounds extend more than 30 feet (9 m) above the water; it is so large now that it is split in two only at high tide. Mound Key itself is estimated to consist of several millions of shells, mostly from oysters.

Before Europeans arrived here in the 16th century, this shell island was called Calos by the Calusa people who lived there and developed it into a thriving maritime city.

4. Sitka (Alaska)

Sitka National Historical Park preserves the battlefield of the 1804 Battle of Sitka, which was fought between Tlingit warriors and colonial Russian troops and was the last major armed conflict between Europeans and people native to Alaska. At that time, Russia claimed to own Alaska (they sold it to the United States in 1867). The battle was sparked when Russian fur traders encroached on tribal territory by building a fort at Sitka in 1802, but the Tlingit destroyed the enemy fort and expelled the Russians.

They then built their own fort to withstand the expected Russian counterattack, but they were forced to abandon it when they were bombarded by Russian ships in 1804. The dispute continued for several decades and was only fully resolved when the United States purchased Alaska.

5. Walnut Canyon (Arizona)

This site preserves more than 80 cliff dwellings built by the Northern Sinagua people between A.D. 1125 and 1250. People can reach the site by following a walking trail through a deep limestone and sandstone gorge about 10 miles (16 km) southeast of Flagstaff. The cliff dwellings were constructed inside natural caves in the limestone, which gave them insulation against cold and heat, while their location high above the canyon floor was defensive.

Strobel said Walnut Canyon is a lesser-known site but a remarkable example of Indigenous Americans overcoming relatively dry conditions by carefully managing water. The inhabitants of the caves farmed crops on the flat land along the canyon rim but took water from the river at the bottom of the canyon to fill cisterns.

6. Chimney Rock (Colorado)

Chimney Rock is a single feature within a large forest that contains more than 80 archaeological sites of the Ancestral Puebloan people. The rock itself is one of two natural spires (the other is named "Companion Rock") that were used roughly 1,000 years ago to mark the position of a "lunar standstill" every 18.6 years ‪—‬ a key astronomical observance among Indigenous Americans, Strobel said.

A multiroom "Great House" made of sandstone, clay and timber ‪—‬ in exactly the style of Chaco Canyon, about 100 miles (160 km) to the south ‪—‬ stood on a ridge near the rock spires, with sweeping views of the surrounding territory. Archaeologists think the Chimney Rock settlements made up a regional ceremonial center, with common people in the lower valley supporting elites who lived on the ridge and watched the skies.

7. Blackwater Draw (New Mexico)

Blackwater Draw is the main archaeological site with evidence of the Clovis culture, which was once thought to be the oldest Indigenous culture in the Americas. The Clovis people (named after the nearby town of Clovis) lived there about 13,000 years ago, and archaeologists have found evidence of the stone and bone tools they used and the animals they hunted, including mammoths and dire wolves. The first evidence of the Clovis people was found nearby in 1929, and at Blackwater Draw itself in 1932.

However, later archaeological finds predate this evidence, and the discovery of footprints at White Sands National Park in New Mexico now seems to confirm that there were humans in this region up to 23,000 years ago, long before the Clovis people.

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

This wooden figurine was discovered in 1977 in an early house built by the ancestors of the Inuit on Baffin Island in northern Canada. The unique carving represents a person wearing European clothing and a cross on their chest. Dated to 1350, the figurine is the earliest Indigenous representation of a European anywhere in the Western Hemisphere and probably depicts a Norseman.

The tiny driftwood carving, which is currently on display at the Canadian Museum of History, measures just 2.1 inches (5.4 centimeters) tall. According to the museum, the featureless face and stumpy arms are common in 14th-century Inuit carvings, but the depiction of a non-Inuit is unique.

The mysterious figure wears a long robe or tunic with a cross on the front ‪—‬ a garment that is similar to those worn in the 11th to 13th centuries by Norse Christians from Greenland. The Norse sagas mention a place called "Helluland," which Leif Eriksson (also spelled Erikson) visited in the early 11th century and is most likely Baffin Island.

Around A.D. 1000, Norse explorers landed in what is now Newfoundland and set up camp at a site archaeologists call l'Anse aux Meadows. Wood buildings and remains from iron production are all that is left of the earliest European settlement in the Americas.

The Norse likely made multiple trips from Greenland to Canada over the centuries in order to trade metal and cloth with the Inuit's ancestors, known as the Thule, and procure walrus ivory in return, as European-origin artifacts have been found in early Inuit houses on Baffin Island. But the Norse eventually abandoned their westward trade routes, possibly due to the resistance of the Indigenous people and the long distance.

This wooden figurine may commemorate a meeting between the Inuit and the Norse and is especially important because it was crafted long before sustained contact in the late 15th century, according to the museum. It is also the earliest evidence of the Indigenous perspective of visitors from the east, revealing which characteristics of the Norse the artisan observed and felt were important to depict.

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

Can you put together last week's Astonishing Artifact?

When Christopher Columbus made landfall in the Americas on Oct. 12, 1492, he encountered Indigenous Lucayans living on the Bahamian island now called San Salvador. Columbus wrote in his diary about "great multitudes of men" who greeted him that day, bartered with him and told him about other groups who lived on nearby islands.

But within a few decades after Columbus' arrival, the Indigenous people of the Americas were decimated by what anthropologist Eric Wolf called the "Great Dying" — a combination of epidemic disease, warfare and enslavement that led to a rapid decline in the Native population.

For centuries, researchers have been trying to figure out how many Indigenous people lived in the Americas just prior to the fateful arrival of European colonizers.

The answer to that question has been surprisingly elusive, and estimates based on historical censuses, archaeological sites and land carrying capacity in the Western Hemisphere have varied wildly.

Recent research into Native American demography has revealed that the population peaked several centuries before Europeans showed up on the shores of North America — and that if Europeans had arrived at that peak, the entire history of the continent may have been different.

Early estimates of the Indigenous population

People have lived in the Americas for at least 14,000 years, having entered the continents via the region around the Bering Strait. Archaeological evidence shows these first Americans dispersed throughout the newly encountered lands fairly quickly. But what happened to the population between that dispersal and the arrival of Columbus is a huge unknown; estimates of the number of Indigenous people living in the Western Hemisphere in 1492 have ranged from 1 million to 112 million people.

"We don't have good quantitative estimates," George Milner, an anthropologist at Penn State, told Live Science. "The numbers are all over the place."

One of the first modern researchers who attempted to quantify the Indigenous population prior to Columbus was anthropologist Henry Dobyns. In a 1983 book, Dobyns used estimates of how many people each type of landscape could support as well as historical records of 16th-century disease epidemics to arrive at an Indigenous population estimate of around 112 million people — more than 100 times larger than some previous experts had believed.

"In essence, Dobyns filled up the landscape to its maximum carrying capacity, so that all environmentally similar places were occupied by the same number of people," Milner said. "He also made the assumption that epidemic disease spread widely and universally, which would make sense if the landscape was filled up."

But a burst of archaeological research in the 1970s and 1980s revealed that the Americas were not uniformly settled, Milner said. Dobyns' estimates were therefore much too high.

Researchers then began to focus on creating population estimates for specific regions of the hemisphere, using techniques such as the relative density of pottery sherds at a site, the number of stone tools and flakes, the number and size of houses, and mortality trends from human skeletons.

In a 2019 study, geographers compiled 129 population estimates from 82 published studies to model the hemisphere-wide distribution of the Indigenous population in 1492. The researchers split the hemisphere into seven regions — the Caribbean, Mexico, Central America, Inca territory, Amazonia, North America and the rest of the Americas — and reached a combined estimate of 60.5 million. Their estimate for North America (modern-day Canada and the U.S.) was about 3 million to 6 million, less than one-third of Dobyns' estimate of 18 million.

A regional perspective – North America

The 2019 study found that the most populous groups in the Western Hemisphere in 1492 were the Aztecs, largely in modern-day Mexico; and the Inca, who lived along the west coast of South America.

But the people we know the most about from an archaeological standpoint are Indigenous groups in the U.S. and Canada.

In a 2010 study, Milner and geographer George Chaplin zoomed in on the data from eastern North America, compiling historic group sizes and sizes of archaeological occupation areas to estimate the location and size of "population aggregates." Using this method, their overall estimate for the eastern U.S. and southeastern Canada was about 1.6 million people.

"Our mean estimates," Milner and Chaplin wrote, "indicate that North America held roughly 2.8 to 5.7 million people" or a "best estimate" of 3.8 million people in the early 16th century, before European diseases dramatically decreased the size of the Indigenous population.

"If you want to start estimating specific populations, you should use measures that work across regions," Robert Kelly, an archaeologist at the University of Wyoming, told Live Science. "People produce things that can be carbon-dated everywhere, because everyone had to build fires for heat and for cooking."

Charcoal from hearths is one of the main human-made things that archaeologists use to radiocarbon-date a site. The radiocarbon data provides a range of dates showing when the firewood was likeliest to have been used.

In North America, many of those carbon-14 dates from charcoal, as well as from animal bones and plant remains from archaeological sites, have been entered into the Canadian Archaeological Radiocarbon Database (CARD).

In a 2009 study, Matthew Peros, a geographer at Bishop's University in Quebec, and co-authors mathematically combined the radiocarbon date ranges in CARD to generate a single curve that revealed how common C-14 dates were over time. At the time, CARD had about 25,000 records.

Because time periods with more people most likely produced more material that could be carbon-dated, the shape of the radiocarbon date curve gave the team an idea of when the population of North America increased and decreased.

They found that the population of North America increased rapidly around 50 B.C. and peaked around A.D. 1150. From that time until European contact, the Indigenous population may have been declining, possibly because of increased mortality from diseases like tuberculosis as people aggregated into denser settlements.

"The 1150 date was an interesting finding that also surprised us," Peros told Live Science. "I had assumed it would be more like 1500 just following the arrival of the Europeans."

In a 2025 study, Kelly and co-authors found a similar temporal peak. By that time, CARD's dataset had ballooned to over 100,000 dates, making the estimate more robust.

"Although devastated by European contact, the Indigenous population did not simply increase to a peak at 1500 CE and then decline," the researchers wrote in the study. In fact, they found evidence for a slight recovery in population numbers just prior to 1500.

But how large was that population? By combining the radiocarbon date curve with a starting population and factoring in average annual population growth, researchers can estimate the number of people living in North America around 1492, Peros said.

In their study, Peros and co-authors assumed that a handful of extended families — around 1,000 people — entered North America about 15,000 years ago as the founder population. With those inputs, the researchers estimated that the maximum population of North America was about 2.5 million in 1150 and had declined to about 1.8 million in 1492. But if people arrived significantly earlier than 15,000 years ago — which might be the case, given evidence from sites like White Sands in New Mexico, which dates to 23,000 years ago — or arrived in greater numbers, those population figures would be even higher.

"Had Europeans tried settling the continent at A.D. 1000, they would have run into a much, much larger Indigenous population," Kelly said. At that time, the city of Cahokia, near modern-day St. Louis, encompassed 6 square miles (16 square kilometers) and had a population of nearly 20,000 people.

"They could have fielded thousands of warriors, and it would have been a very different experience for the Europeans," Kelly said. "It could have been a very different history."

Why does this matter?

Experts told Live Science that the pre-1492 population of what is now the U.S. and Canada was between 2 million and 4 million. The archaeological deep dive in this region sets up the possibility that a full Western Hemisphere population estimate may be made someday.

Milner is optimistic they'll eventually get there. "Will it be done in my lifetime? Probably not," he said. "It's time-consuming, laborious and not especially flashy work to do."

Nonetheless, demography is important work, he said, because it can help us make estimates to prepare for the future.

"The world's population has more than doubled in my lifetime; that's unheard of in human existence," Milner said. "Environmental scientists are really trying to look at what's happened over long periods of time to give us a range of variation of what might happen in the future. We have to make some informed decisions about how to manage our landscape and accommodate these changes."

Understanding the number of Indigenous inhabitants in the Western Hemisphere in 1492 is also key to understanding the history of North America.

"North America was not an empty continent when the Europeans arrived," Peros said. "There were people and civilizations pretty much everywhere in the Americas for a long period of time. It is important for people to understand that when we talk about questions of reconciliation and when we do land acknowledgements."

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

Since the discovery of their remains in the 19th century, Neanderthals have fascinated scientists and the general public alike. Although our understanding of these ancient hominins has been transformed tremendously since then, how we have viewed this other human lineage became deeply entrenched in how we see our own species, with geopolitical events shaping the rhetoric around our ancient relatives.

In his new book, "Neanderthals Among Us: The Making of a Prehistoric Human" (Oneworld Publications, 2026), historian and author Peter Sahlins examines our complicated view of Neanderthals, with this lost human lineage being viewed through the lens of cultural and political ideologies. In this excerpt, he looks at our theories for why they went extinct and the philosophical reckoning we've placed up on them.

Between violent extermination and peaceful absorption — with cultural exchange — prehistorians and others propose a wide range of theories to account for Neanderthals' extinction. Just as we've projected our concerns and anxieties about race and gender onto Neanderthals, so too do contemporary challenges shape how we imagine their extinction.

Sometimes it's the newspapers that translate a more neutral science into easily relatable headlines. "Immigrants Halt Neanderthal Era," announced the Glasgow Herald (29 July 2011), claiming that "Europe's earliest residents may have been crowded out by uncontrolled immigration 40,000 years ago." Glossing a highly technical study by Cambridge archaeologist Paul Mellars about the notable increase in population size during the Upper Palaeolithic, the news reports tweaked the science to speak to contemporary anxieties.

But often the science itself is framed or informed by current events. The pathogen thesis gained credence during and after the COVID-19 epidemic. A 2024 study of a 50,000-year-old case of herpes in a sequenced viral genome confirmed widespread speculation that Sapiens-borne pathogens were passed to a Neanderthal population without immunities. Jonathan Kennedy's popular world history "Pathogenesis" (Crown, 2023) argued that Homo sapiens would have been less vulnerable to Neanderthal diseases because they arrived in much larger numbers and had more evolved immune systems from their tropical environment.

Of growing importance over the last twenty years is the thesis that climate change, our own existential challenge of the Anthropocene, was the principal cause of Neanderthal extinction. The idea takes many shapes, beginning with an update of French geologist Georges Cuvier's "catastrophism," where species died off in cataclysmic geological events like earthquakes and volcanic eruptions. Since 2007, researchers point to the Campanian Ignimbrite eruption near Naples (Italy), now dated to around 39,280 BP [before present] (+/- 110 years), fictionalised in the 2013 animated film The Croods.

Scientists argue that arriving Homo sapiens were not as affected, perhaps because there were fewer directly touched by the 120 cubic miles [500 cubic kilometers] of magma released, or perhaps because almost everyone died out — but waves of Sapiens arrived later. After all, while most of us share small parts of the Neanderthal genome, the lineages from which we 'directly' descend settled much later in Europe — long after the Ice Age. By far, the greatest portion of our genome comes from our Neolithic, not Palaeolithic, ancestors.

But perhaps "Climate Change Killed the Neanderthals," that is, the extreme climatic fluctuations during the Upper Pleistocene that National Geographic (9 February 2004) announced, following the work of an international team of thirty scientists who laboured for more than seven years on the study. The team identified a general climatic instability during the Middle Palaeolithic marked by a severe cooling event around 41,000 years ago, lasting six centuries — interstadials GIS 13 to 7 of the Greenland ice-core records, to be precise.

For the last twenty years, scientists have sought to specify the timing, magnitude and ecological impact of a "mini-Ice Age" — the prehistorical obverse of global warming — that reduced vegetation and herbivore food sources, forcing Neanderthals towards warmer climates, including southern Spain. Clive Finlayson, trained as a zoologist, was an early contributor to sophisticated ecological modeling of Neanderthal extinction. At Gibraltar, he argued, "the last Neanderthal" could be found as late as 29,000 years ago, but there's competition for the title: elsewhere in the southern climatic refugium, Zafarraya (Granada) yielded a skeleton dated to 30,000 BP, but there are skeptics, while other candidates come from the Mezmaiskaya Caves in the Caucasus.

The trope, we've seen, is a frequent one in Neanderthal fiction, including Claire Cameron's "The Last Neanderthal" (Little Brown & Co., 2017), a moving, feminist revision of "Neanderthal Woman." It's also been widely used in popular nonfiction, including in Ludovic Slimak's 2023 account of twenty-five years of research in the Mandrin Cave .

Some of the science blaming climate change for the demise of Neanderthals marks a retreat from the recent archaeological rehabilitation of Neanderthals as a type of human equal to Homo sapiens, as these theories need to account for Sapiens' survival in the same severe conditions. Some experts rewrite basic wisdom, arguing that Neanderthals were not a cold-adapted species, since their origins lay during a warm interglacial stage (MIS 11); or that they lacked the technologies for making complex (and warm) clothing; or perhaps that their preexisting biological cold adaptations delayed the development of such technologies — a story about their technological inertia and deep conservatism.

That Neanderthals died out because of their conservatism, while humans alone mastered innovation, and with it, conquered the world, is the principal claim in Philip Lieberman's "The Unpredictable Species: What Makes Humans Unique" (Princeton University Press, 2013), and it's a widely shared belief.

Aside from the fact that the high value placed on "innovation" corresponds to the ideological superstructure of contemporary neoliberalism and late-stage capitalism, it seems fitting that Neanderthals died out because, in this view, they were, well, truly Neanderthal. The rhetorical figure returns to haunt the science: Neanderthals were conservative, backward, clinging mindlessly to the past in a changing world.

Neanderthal conservatism — not rhetorically, but as an original character trait — has origins in nineteenth-century anthropological judgements about "primitive" peoples. Augustus Pitt Rivers, an early innovator in British archaeology, underscored "the form of a persistent conservatism" of indigenous peoples, and quoted approvingly his colleague E. B. Tylor's "Primitive Culture" (1871): "The savage is firmly, obstinately conservative. No man appeals with more unhesitating confidence to the great precedent-makers of the past; the wisdom of his ancestors can control against the most obvious evidence of his own opinions and actions."

Just as "savages" were once seen as descendants of Neanderthals, so too is their conservatism a cultural legacy, even when anthropologists, transcending an outdated comparative method, no longer deem them ancestral, or even savage.

NEANDERTHALS AMONG US: The Making of a Prehistoric Human by Peter Sahlins is published by Oneworld, hardback £28.

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What color is the moon? Ask an Earthling, and you'll get a predictably monochromatic answer: white or gray.

But ask the four crewmembers of NASA's Artemis II mission — who spent nearly seven hours circling the moon from just 4,000 miles (6,400 kilometers) from the lunar surface this April — and you'll wonder if they're talking about the same dusty satellite we can see from Earth.

Yellow, brown, green, blue and tan features fan across vast volcanic plains and lurk at the edges of ominous craters, according to the crew's in-the-moment observations, which were shared this week in NASA's Artemis II Preliminary Lunar Science Report. The 130-page document catalogs everything crewmembers Reid Wiseman, Victor Glover, Christina Koch and Jeremy Hansen saw during their historic close flyby of the moon on April 6, drawing from 814 gigabytes of photo, video and audio recordings taken from the Orion crew capsule.

This rainbow of lunar color represents distinct geological features that could inform future missions on where to land and where to explore as the world's space agencies race to set up a permanent presence on the moon.

One spot that particularly enthralled the astronauts (and is featured in the image above) is the Aristarchus Plateau — a broad, elevated region on the northwestern edge of the moon's nearside. The region hosts one of the moon's densest collections of ancient volcanic features, including swaths of dark lava deposits and colorful volcanic glasses.

Koch, mission specialist for Artemis II, was shocked to see distinct yellow shades in the region; she likened the plateau to "a yellow snow-capped mountain," with sunlight-reflecting craters providing the bright "snow." She went on to call the region "a jaundiced cheek of the Moon."

"There are so many colors now," Glover, Artemis II's pilot, added while photographing the area. "There's also a green. I see brown, especially Aristarchus and north toward the north pole. … It kind of flows down from the north in brown streaks."

According to the report authors, these colorful hues "could be associated with orange (titanium-rich) and green (magnesium-rich) glass beads respectively," similar to volcanic glass beads collected by the Apollo 15 and 17 missions on separate parts of the moon.

"Chaos across the entire area"

Another colorful patch of the lunar surface that caught the crew's attention was Orientale Basin — a huge, young and multiringed impact crater that's about three times as wide as Massachusetts, according to NASA. Straddling the moon's near and far sides, this massive bull's-eye is rarely visible from Earth, but it dominated the crewmembers' field of view as they orbited around the side of the moon.

"It has just created chaos across that entire area," Wiseman, commander for the mission, said at the time.

When flying over this sprawling basin, the crew noted gray, brown, tan and green below. The largest, outermost ring in the basin contained "almost swamp-like colors," Koch reported, while Glover spotted what looked like "dusted peaks" and "white on the very edges of [the mountains], the spines, the ridgebacks." Chains of craters parading away from the impact site looked "like bubbles rising from a team of scuba divers below," Koch added.

While these may sound like off-the-cuff observations, the Artemis II crew spent more than two years training to study and describe the moon's geology. Their regimen included visiting craters on Earth, taking lessons individually and in classrooms, conducting simulated flybys and, according to the report, bringing "self-selected reference materials" into the Orion capsule to read on the way to the moon.

Thanks to this training, the crew's observations provided a wealth of scientific information that no autonomous camera or orbiter could, the report said.

"The Artemis II mission demonstrated the exceptional value of human observation and cognition as scientific assets in planetary exploration," the report authors concluded. "Unlike cameras, which capture isolated moments and often narrow subsets of a scene, human observers continuously interpret their surroundings, integrating realtime visual perception with contextual understanding."

Or, to put that in Glover's more relatable words to mission control, "It's quite a wicked view."

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

Aqueducts are some of the ancient Romans' most prominent surviving archaeological remains. These aqueducts relied on gravity to bring down the water to cities gradually. But some, such as the aqueduct at Aspendos in Turkey, had sections where they had to go uphill. So how did the Romans get water to flow upward?

The Romans used a few methods, including siphons and various water-lifting devices, experts told Live Science.

Inverted siphons

One strategy was a system called an inverted siphon (sometimes simply called a siphon).

At Aspendos, in southern Turkey, there is a second-century-A.D. Roman aqueduct with inverted siphons that scholars have reconstructed with a virtual modeling simulation. To get water through a valley, the Romans built a "header tank" on one end of the valley and a slightly lower "receiving tank" (or "outlet tank") on the other side. In the valley, they constructed two towers between the tanks, Paul Kessener, a researcher in the Department of Language and Culture Studies at Radboud University in the Netherlands, noted in an article published in 2000 in the Journal of Roman Archaeology.

As water dropped down a steep hill, the resulting pressure pushed it up the first tower before dropping it steeply down the other side, with the force allowing it to climb the second tower. The water eventually reached the receiving tank on the other side of the valley and continued toward the city of Aspendos.

It was important to prevent air pockets from forming as the water went through the inverted siphons. The header and receiving tanks were relatively large, allowing air bubbles to escape, Giovanni De Feo, a professor of industrial engineering at the University of Salerno in Italy, noted in an email.

"As the flow entered a relatively large chamber, its velocity decreased, allowing air bubbles to rise naturally to the water surface and escape through the open top of the structure," De Feo explained. This reduced the risk of air pockets forming.

The Romans tried to avoid using inverted siphons, said Charles Ortloff, a research associate in the Department of Anthropology at the University of Chicago who has a background in both engineering and history. When "Roman engineers encounter a valley, rather than construct a siphon, they [preferred] to build a bridge with a top channel to cross a valley," Ortloff said in an email. One example of this is at the Segovia aqueduct in Spain, which has a stunning bridge that still survives today.

Roman water-lifting devices

While the Romans used inverted siphons to move water upward in an aqueduct, they employed other devices to push water out.

Perhaps the best known of these devices is the Archimedes screw, which was sometimes used to help lift water from rivers to fields. (It was allegedly designed by Archimedes, a Greek inventor who lived during the third century B.C. However, it might have actually been invented at an earlier time, noted historians Stephanie Dalley and John Peter Oleson in a 2003 paper.) When "turned by use of animal power, [it] can effectively raise water from lower river heights to higher land area heights," Ortloff said.

The Archimedes screw "consisted of a wooden shaft that had [curves] of thin and flexible willow or wicker branches one stuck on top of the other, so that an endless screw was created," the Kotsanas Museum of Ancient Greek Technology's website notes. This screw was placed within a wooden pipe, and the "device was placed in the water with an inclination of 30 degrees," the museum representatives wrote. As the screw was rotated, it lifted the water.

Water wheels were also used to lift water, including in Roman mines. "The water wheel is a device that raises water and that is made up of several buckets that are fastened to a big wheel," scientists wrote in a 2024 paper. This "kind of wheel resembles a carriage wheel but it is larger and features buckets to catch water in addition to its larger size," they explained.

Another device, sometimes known as Ctesibius' pump, "was hand-moved, operating a wooden lever with a swinging motion," the scientists wrote. It had two cylinders connected to a central chamber through pistons, and the driven water exited through a nozzle connected to the central chamber.

Whatever method was used, the Romans would not let an uphill climb stop them from bringing water where they wanted it to go.

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

For decades, photojournalist Steve Winter has traveled across the world capturing incredible images of big cats as part of his work for National Geographic. Yet he didn't photograph an animal professionally until he was 34.

"If anybody had said, 'You're going to work with big cats for 25 years of your career,' I would have said 'No, I don't know anything about big cats,'" he told Live Science. "But I learned from scientists and local people," he added. "That was very, very important — that's what, to me, was the biggest change in my life."

Together with his wife, author and environmental journalist Sharon Guynup, Winter has helped change laws around big cats in the U.S.; revealed the horrors of the Tiger Temple in Bangkok, resulting in its closure; and took an iconic photograph of the cougar P-22 beneath the Hollywood sign, which eventually led to the creation of the world's largest highway wildlife corridor over Highway 101 in California.

In their new book, "Big Cats" (National Geographic Books, 2026), Winter and Guynup provide a retrospective of their careers, looking at the fragility of these predators, the conservation work helping to save them, and the challenges they still face. Live Science spoke with Winter about his career, the changes he's seen, and why he's hopeful for the future.

Hannah Osborne: You've traveled all over the world and seen so many things. Is there one photograph that really sticks out for you, one that you come back to and think about?

Steve Winter: I always look at the images that have had an impact at the time. That makes a huge difference to me, because in the end, I know that in taking this [photograph], not only did I succeed beyond my wildest expectations, but it's making a difference in the world. Right now, I have just been putting remote cameras up on what will be the world's largest wildlife overpass, and that was started by my Hollywood cougar picture of P-22, Puma 22, under the Hollywood sign. [Editor's note: The common names cougar, puma and mountain lion all refer to the same species, Puma concolor.]

That changed so much in Los Angeles. I've never seen a city be transformed in their love for the fact that they have a mountain lion in a park in the city. What came of that was [people] thinking, "Hey, maybe we should connect these areas where these animals are living." [Editor's note: The Wallis Annenberg Wildlife Crossing over the 10-lane Highway 101 that was inspired by the cougar P-22 is due to open Dec. 2.]

To think about that is pretty amazing, so right now, P-22 and the Hollywood cougar is my go-to image.

He became a celebrity in the land of celebrities; people loved him. There's a P-22 day; schools are using urban wildlife in their curriculum. The LA Natural History Museum has a permanent exhibit, and what is right in the center of it? The Hollywood cougar picture.

HO: How did the P-22 photograph come about?

SW: As wildlife photographers, we will often go to these meetings where people are gathering to save elephants, to save this, to save that. So I went to meet the scientists that worked with these cats in the largest urban park in the United States. I asked Jeff Sikich, a biologist for the National Park Service, "[Do] you have a lot of trails in that park? Do you have any that the cats walk on where you could see the lights of LA in the background?" He kept saying no.

When you're working with camera traps, it's very important to visualize the picture in your mind that you're after [when] you visit a spot. I just said, "Well, Jeff, you know what would really tell the story of urban wildlife is if we had a mountain lion under the Hollywood sign." He looked at me like I'm crazy, and said, "There's no mountain lions in Griffith Park." I said, "If anything changes, let me know."

Eight months later, I got a text. They had a trail camp set up to census bobcats [Lynx rufus] in the park, and there was P-22.

With camera traps, you don't need to sit, and I learned that from the beginning. For the second story I did, it was photographing a quetzal, which is a sacred bird of the Maya and the Aztecs. I knew nothing about birds, either. It's got a meter-long [3 feet] tail. I was enamored by the fact that it had a historical background — they used quetzal feathers as a form of currency; they were sacred birds.

I loved all that, but working on that story in a cloud forest in Guatemala on top of a mountain all by myself, every morning I'd come down and set my camera up on the tripod [near the bird's nest], and then take it away at the end of the day. I'd walk back, and all of a sudden, the hair on the back of my head would stand up and on my arm, and I'd get this tingling feeling and it's like, what's going on? I'd turn around. You can't see anything in a rainforest or a cloud forest because the proliferation of life is everywhere. One night when I'm reading my book in the one room shack that I was staying in my bunk bed, all I hear is the stairs creaking. Then I hear the floorboards creaking. Then I hear scratching, and then sniffing, outside the door.

I grabbed the walkie-talkie to call Juan Carlos, the naturalist that I was working with. He would find the quetzal nests for me. I asked him, in Spanish, "Juan Carlos, what is this?"

And he said, "Oh, Steve, don't worry; it's just a black panther [Panthera onca]." I've been there five weeks, and I said, "Well, how come it took you so long to tell me there was a black jaguar here?" And he said, "We didn't want to worry you."

HO: Throughout the book, you look at topics like poaching, captive tigers in the Tiger Temple in Thailand, and the way they're kept in the U.S. for entertainment. And a lot of these things are still going on. How do you cope with seeing that side of their lives?

SW: When I was first working on tigers, I was in Thailand. I was wanting to work in Thailand and Sumatra because they were the two subspecies that experts said may go extinct. I was working with the most incredible group of scientists I've probably ever worked with. They were trying to save the Indo-Chinese tiger [Panthera tigris corbetti] in Thailand.

But close by was this place called the Thai Tiger Temple. And I said, "Hey, guys; I'd like to go there." And they said, "No, Steve; don't go. These are bad people, and we think they're involved in the black-market trade of tiger parts and tigers to Laos and then into China."

That's a good reason for me to go if you don't want me to go. The first thing I saw was this huge sign that said "conservation." This was a Buddhist monastery. For some reason, the abbot had been given a tiger cub about 10 years before, and he fell in love with tigers. So they started a tiger tourism operation that brought in at least $3 million a year.

I could see something was fishy right away, because by then, I'd learned a lot about these cats. They kept saying that they always had 150 tigers. But you could pet tiger cubs for Instagram selfies or bottle-feed them 365 days a year. If you're breeding tigers, what are you going to have? More tigers. Something was happening to them, because the death rate wouldn't take over the birth rate when you're speed-breeding cubs, which is what they were doing. A female has cubs; they take them away immediately so she'll be ready to have another litter. You can only use the cubs for three months because after that, they're too big to pet.

They had all these tourist things where you could get a selfie with a head of a tiger in your lap. I was saying, "Why are these tigers acting so sleepy?" They're taking this giant head of a tiger and putting it in somebody's lap that's sitting on the concrete. You would think that if you put the head of a tiger in your lap, you're going to end up with your head in their mouth.

[Editor's note: Winter and Guynup worked together on an investigation into the Tiger Temple in 2016, which eventually led to it being exposed for its abuse and connections with the illegal wildlife trade. Shortly after, the Tiger Temple was shut to the public.]

Sharon did the investigation, and I already had pictures. But we went to do a video and go visit the temple again … By the time we got done, the TV stations in Bangkok had taken the video and showed it all over on the nightly news. We kept working on this, and Sharon wrote four more stories. And after the last one, the Thai government was inundated with people calling for the prime minister to shut it down. They went in with the army and the police, and what they found was horrific. They went to the freezer. There were tigers hanging on meat hooks, cubs in jars, with a little Thai flag on them. They shut it down.

Stopping this is really important. After that, we did a story on tigers in the U.S., which was very difficult psychologically. It was one thing to see them in Thailand, but we had always heard that there were more tigers in the United States than there are in the wild, and people would go, "What are you talking about? We don't have tigers here."

Sharon and I … we found a lot of the same speed-breeding cubs at these roadside zoos, whether it was Doc Antle's Myrtle Beach that was $500 a day, or some dumpy little place on the road down south where you can give them $10 to look at a tiger. They were everywhere.

After that story came out, the National Geographic Society gave a copy of this 30-page story that we had done for the magazine to every member of Congress. We got this text on 20th December, 2022, that President Biden had signed the Big Cat Public Safety Act, which outlawed all that. We were part of getting this law passed, which was incredible.

HO: What are some of the biggest changes in conservation you've seen over your career?

SW: Conservation was changing a lot in the '90s and 2000s. Alan Rabinowitz [a zoologist who served as the president, CEO and chief scientist at Panthera Corp., a nonprofit conservation organization devoted to protecting wild cats] had this idea after he had a lot of scientists in Central and South America give him data on where they were working and where jaguars were. When he took it away and just showed the locations, he goes, this is a corridor, a natural corridor, because now we're talking a lot about connectivity and how roads get in the way. It's like animals are in prison because they can't cross these big freeways or even small ones. Find out where animals are, their migrating paths, and put in an overpass or an underpass or something.

All this was happening, all this new science, new conservation. That was all spearheaded by the work of [biologist and conservationist] George Schaller, who became a friend of ours. What a life that we've had — and are having. We're still working on the connectivity part right now.

HO: Are you hopeful for the big cats in LA?

SW: Oh, definitely. The ones that live in the Santa Monica National Recreation Area will be able to cross the 101 and then go all the way to San Jose. They could actually then hug the top of a certain mountain and get close to San Francisco, which is incredible to think about now. It's a huge metropolitan area, so you're leaving one, going to another. But there's so much land in between, and they can cross safely.

HO: What made you specialize in big cats in the first place, and what's the draw that keeps you coming back?

SW: Big cats are so charismatic and, to me, mystical. And they're an umbrella species, so if you save the largest predator, which is usually a big cat in any landscape, you save everything underneath it.

I was just taken over by these animals. National Geographic had never done a jaguar story before. I found out really quick why: You can't see them. I tried to use remote cameras, camera traps, but they're really smart. They'll go around them, so they don't have the flash going off or they don't like the sound or the smell of meat on these waterproof boxes and the cords and all that.

I just fell in love with big cats, and what a life to be able to work with every one of them. The only one that was on my list that I haven't done is the Amur tiger, Siberian tiger [Panthera tigris altaica]. When I was ready to photograph them with the scientists that had been monitoring them for over a decade, [the tigers] got canine distemper and about 60% died.

Big cats really bounce back when you give them protection, and there was protection given after you lose this many. All the study tigers that had the GPS collars on, the ones they could monitor, died. But the population bounced back, and there's more now than there were before.

I won't get to photograph Amur tigers. And the reason is, there's people — locals — who are working on it, and they're doing an incredible job. I've got a book here that has all the cats that I've worked on. The impact these stories have had, and the change that's come about, is what really makes me proud.

This interview has been condensed and edited lightly for clarity.

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The written word is one of humanity's most important information technologies. Without it, mathematical and scientific discoveries would be lost to history. But it can also lock ideas in place long after they've stopped making sense.

So does writing speed up cultural change or slow it down?

Russell Gray, a professor in the Department of Linguistic and Cultural Evolution at the Max Planck Institute for Evolutionary Anthropology in Germany, heads a research project investigating how writing affects the way languages change. His team uses methods borrowed from evolutionary biology to trace languages through family trees — similar to the way biologists trace species.

Language is one element of culture that researchers can measure to determine whether writing speeds up or slows down cultural change.

"The obvious answer," Gray said, is that writing slows culture down because writing "is all codified and specified and people get trained in it." Gray doesn’t think the obvious answer is necessarily the right one. But other researchers agree that writing can lock in ways of thinking.

"Writing can lead to what learning psychologists sometimes call 'canalization,'" Charles Perreault, an associate professor in the School of Human Evolution and Social Change at Arizona State University, told Live Science in an email. "It can narrow the range of ways people think about a problem. When a rule, method, or story is written down, people may come to see it as the correct version … and may not even consider that a better or different way could exist."

Religious texts and legal codes are good examples. In both cases, the interpretation of rules written hundreds ‪—‬ or even thousands ‪—‬ of years ago shapes the way things are done, long after the circumstances that produced them have changed.

This idea shows up in artistic expression, too: A 2017 analysis by ethnomusicologist Patrick Savage looked at more than 4,000 British-American ballads from the 16th through 20th centuries and found that written melodies changed less than those shared through oral tradition.

But there are also ways that writing may speed up cultural change.

"Before writing, much cultural knowledge had to be stored in people's brains," Perreault said. "That has obvious limits."

People forget things they don't study routinely, and when people die, their knowledge often dies with them. Because writing moves information storage beyond the human brain, it can reduce those losses, Perreault said.

"If writing prevents knowledge from being lost, and if it also helps information spread through a society, as with the printing press, then it could accelerate the ratchet effect of cumulative cultural evolution," Perreault said. "But this remains, to some extent, a hypothesis."

By the book

One reason the question of whether written language speeds or slows cultural evolution is that writing is hard to separate from everything that comes with it.

Writing has been separately invented only around four times in human history — although "some people argue there's a fifth in India," Gray said — which means nearly every writing system on Earth descends from that handful. Those systems spread through contact; trade, war, religion and the other ways humans intermingle had their own effects on cultural change that are hard to untangle from the effects of writing.

Also, "mass literacy is quite recent," Gray said. "If you've got these written varieties that are just used by, often, religious elites, that's potentially going to have much less impact."

So which force wins? Both experts think writing speeds up cultural change, though neither can prove it yet.

"I would say that writing probably speeds up cultural change overall," Perreault said. Gray agreed, though he acknowledged that most people would guess the opposite.

Still, Perreault cautioned, "these are empirical questions that have yet to be answered empirically."

Flu season is off to an early start in some parts of the U.S., data shows.

In a typical year, U.S. flu activity starts building in late fall — typically in October or November — and peaks between December and February. This year, flu activity is currently low but rising nationwide: During the week ending Sept. 26, 3.4% of respiratory samples tested by clinical labs were positive for flu, according to Centers for Disease Control and Prevention (CDC) data.

That's about seven times the rate that was seen at the same point last year. About 0.5% of samples tested positive during the week ending Sept. 27, 2025.

"This particular year, it appears to be starting early — like right now," Dr. William Schaffner, a professor of preventive medicine and infectious diseases at Vanderbilt Health in Tennessee, told Live Science. Patients at clinics in his area are already testing positive for flu, he said.

The early uptick in flu is mostly unfolding in Western states, including Washington, California and Arizona. In Washington, for example, the share of emergency department visits diagnosed as flu climbed from 0.25% in the week ending Aug. 29 to 1.34% in the week ending Oct. 3, according to CDC emergency department data. That's a more than fivefold increase over six weeks.

Where the flu took off first isn't a warning sign in itself, Schaffner noted.

"There's nothing unusual about flu starting in the West Coast and moving east," he said. Recent seasons have more often begun in the Southeast or Midwest, he noted, but "it can start almost anywhere."

Leading with H1N1

Nowadays, seasonal flu is caused by three subtypes of flu viruses: two subtypes of influenza A, called H1N1 and H3N2, and the Victoria lineage of influenza B. (A second subtype of influenza B used to circulate but is now thought to be extinct.)

Last season, a fast-spreading version of H3N2 known as subclade K dominated. The CDC classified the 2025-2026 season as highly severe for children, as at least 195 children died of flu-related causes.

Schaffner likens influenza A and B to siblings. "They're very related, but they each have their own individual characteristics," he said. Influenza A strains usually cause the biggest outbreaks early in the season, while influenza B strains "kind of smolder along" and account for most cases toward the end, he noted.

This year, H1N1 has taken the initial lead. Of the influenza A samples that public health labs subtyped during the week ending Sept. 26, 96% were identified as H1N1, according to CDC data. That doesn't mean H1N1 will continue to dominate throughout the season; it just gives a snapshot of what's happening now.

The dominant strain matters because flu is "a moving target," said Dr. Paul Offit, director of the Vaccine Education Center at Children's Hospital of Philadelphia. The virus constantly mutates — especially hemagglutinin, the protein on the virus's surface that it uses to latch onto human cells. Hemagglutinin is the main target of flu vaccines.

An early start to the season doesn't guarantee it'll be a severe one, either. In its 2026-2027 season outlook, the CDC projected that this season will likely be moderate, although it has only low-to-moderate confidence in that forecast.

When to get vaccinated

Everyone 6 months and older is recommended to get an annual flu vaccine.

Influenza is especially dangerous for children under 5, adults 65 and older, people with chronic health conditions and pregnant people, as these groups are more prone to severe infections. Serious cases of flu can lead to complications such as pneumonia, sepsis, and brain or heart inflammation, and in some cases, they can be deadly. Tens of thousands of people die of flu each season in the U.S.

For flu vaccination, timing matters. The CDC generally doesn't recommend vaccination in July or August for most adults, because the shot's protection can wane over the course of a season. But with flu arriving early, "October is the ideal time to get vaccinated, and even more so right now," Schaffner said.

When circulating strains' features differ from those captured in the vaccine, "that usually predicts a more difficult season," Offit said. That said, it's too early to know if this year's flu shots are a good match for the circulating flu viruses.

Protection begins building right after you get the shot, but it takes up to about two weeks to reach full strength.

How much protection a flu vaccine offers varies by season, depending partly on how well its formulation matches the strains that circulate. Offit said that protection against symptomatic illness varies by age group and that the vaccines are "a little more effective" at preventing more severe illness. In terms of flu cases that prompt people to seek medical care, the shot has been 29% to 56% effective over the past decade, the CDC estimates.

While the vaccines are less reliable at preventing mild cases of flu, Schaffner said, they work best at "keeping you out of the hospital, keeping you out of the intensive care unit, and keeping you out of the cemetery."

The CDC's 2026-2027 guidance keeps its recommendation of an annual flu vaccine for everyone 6 months and older, with high-dose and adjuvanted shots preferred for adults 65 and older. (Adjuvanted shots contain an extra ingredient to help rev up the immune system.)