Archaeology

This is the oldest evidence of people starting fires

Archaeology, firestarting, hominins, making fire, Neanderthals, Science / Mike M. / December 10, 2025

We didn’t start the fire. (Neanderthals did, at least 400,000 years ago.)

This artist’s impression shows what the fire at Barnham might have looked like. Credit: Craig Williams, The Trustees of the British Museum

Heat-reddened clay, fire-cracked stone, and fragments of pyrite mark where Neanderthals gathered around a campfire 400,000 years ago in what’s now Suffolk, England.

Based on chemical analysis of the sediment at the site, along with the telltale presence of pyrite, a mineral not naturally found nearby but very handy for striking sparks with flint, British Museum archaeologist Rob Davis and his colleagues say the Neanderthals probably started the fire themselves. That makes the abandoned English clay pit at Barnham the oldest evidence in the world that people (Neanderthal people, in this case) had learned to not only use fire, but also create it and control it.

A cozy Neanderthal campfire

Today, the Barnham site is part of an abandoned clay pit where workers first discovered stone tools in the early 1900s. But 400,000 years ago, it would have been a picturesque little spot at the edge of a stream-fed pond, surrounded by a mix of forest and grassland. There are no hominin fossils here, but archaeologists unearthed a Neanderthal skull about 100 kilometers to the south, so the hominins at Barnham were probably also Neanderthals. The place would have have offered a group of Neanderthals a relatively quiet, sheltered place to set up camp, according to Davis and his colleagues.

The cozy domesticity of that camp apparently centered on a hearth about the size of a small campfire. What’s left of that hearth today is a patch of clayey silt baked to a rusty red color by a series of fires; it stands out sharply against the yellowish clay that makes up the rest of the site. When ancient hearth fires heated that iron-rich yellow clay, it formed tiny grains of hematite that turned the baked clay a telltale red. Near the edge of the hearth, the archaeologists unearthed a handful of flint handaxes shattered by heat, alongside a scattering of other heat-cracked flint flakes.

And glinting against the dull clay lay two small pieces of a shiny sulfide mineral, aptly named pyrite—a key piece of Stone Age firestarting kits. Long before people struck flint and steel together to make fire, they struck flint and pyrite. Altogether, the evidence at Barnham suggests that Neanderthals were building and lighting their own fires 400,000 years ago.

Fire: the way of the future

Lighting a fire sounds like a simple thing, but once upon a time, it took cutting-edge technology. Working out how to start a fire on purpose—and then how to control its size and temperature—was the breakthrough that made nearly everything else possible: hafted stone weapons, cooked food, metalworking, and ultimately microprocessors and heavy-lift rockets.

“Something else that fire provides is additional time. The campfire becomes a social hub,” said Davis during a recent press conference. “Having fire… provides this kind of intense socialization time after dusk.” It may have been around fires like the one at Barnham, huddled together against the dark Pleistocene evening, that hominins began developing language, storytelling, and mythologies. And those things, Davis suggested, could have “played a critical part in maintaining social relationships over bigger distances or within more complex social groups.” Fire, in other words, helped make us more fully human and may have helped us connect in the same way that bonding over TV shows does today.

Archaeologists have worked for decades to try to pinpoint exactly when that breakthrough happened (although most now agree that it probably happened multiple times in different places). But evidence of fire is hard to find because it’s ephemeral by its very nature. The small patch of baked clay at Barnham hasn’t seen a fire in half a million years, but its light is still pushing back the shadows.

an artist's impression of a person's hands holding a piece of flint and a piece of pyrite, striking them together to make sparks — This was the first step toward the Internet. We could have turned back. Credit: Craig Williams, The Trustees of the British Museum

A million-year history of fire

Archaeologists suspect that the first hominins to use fire took advantage of nearby wildfires: Picture a Homo erectus lighting a branch on a nearby wildfire (which must have taken serious guts), then carefully carrying that torch back to camp to cook or make it easier to ward off predators for a night. Evidence of that sort of thing—using fire, but not necessarily being able to summon it on command—dates back more than a million years at sites like Koobi Fora in Kenya and Swartkrans in South Africa.

Learning to start a fire whenever you want one is harder, but it’s essential if you want to cook your food regularly without having to wait for the next lightning strike to spark a brushfire. It can also help maintain the careful control of temperature needed to make birch tar adhesives, “The advantage of fire-making lies in its predictability,” as Davis and his colleagues wrote in their paper. Knowing how to strike a light changed fire from an occasional luxury item to a staple of hominin life.

There are hints that Neanderthals in Europe were using fire by around 400,000 years ago, based on traces of long-cold hearths at sites in France, Portugal, Spain, the UK, and Ukraine. (The UK site, Beeches Pit, is just 10 kilometers southwest of Barnham.) But none of those sites offer evidence that Neanderthals were making fire rather than just taking advantage of its natural appearance. That kind of evidence doesn’t show up in the archaeological record until 50,000 years ago, when groups of Neanderthals in France used pyrite and bifaces (multi-purpose flint tools with two worked faces, sharp edges, and a surprisingly ergonomic shape) to light their own hearth-fires; marks left on the bifaces tell the tale.

Barnham pushes that date back dramatically, but there’s probably even older evidence out there. Davis and his colleagues say the Barnham Neanderthals probably didn’t invent firestarting; they likely brought the knowledge with them from mainland Europe.

“It’s certainly possible that Homo sapiens in Africa had the ability to make fire, but it can’t be proven yet from the evidence. We only have the evidence at this date from Barnham,” said Natural History Museum London anthropologist Chris Stringer, a coauthor of the study, in the press conference.

a person holds a tiny fragment of pyrite between a thumb and forefinger — The two pyrite fragments at the side may have broken off a larger nodule when it was struck against a piece of flint. Credit: Jordan Mansfield, Pathways to Ancient Britain Project.

Digging into the details

Several types of evidence at the site point to Neanderthals starting their own fire, not borrowing from a local wildfire. Ancient wildfires leave traces in sediment that can last hundreds of thousands of years or more—microscopic bits of charcoal and ash. But the area that’s now Suffolk wasn’t in the middle of wildfire season when the Barnham hearth was in use. Chemical evidence, like the presence of heavy hydrocarbon molecules in the sediment around the hearth, suggests this fire was homemade (wildfires usually scatter lighter ones across several square kilometers of landscape).

But the key piece of evidence at Barnham—the kind of clue that arson investigators probably dream about—is the pyrite. Pyrite isn’t a naturally common mineral in the area around Barnham; Neanderthals would have had to venture at least 12 kilometers southeast to find any. And although few hominins can resist the allure of picking up a shiny rock, it’s likely that these bits of pyrite had a more practical purpose.

To figure out what sort of fire might have produced the reddened clay, Davis and his colleagues did some experiments (which involved setting a bunch of fires atop clay taken from near the site). The archaeologists compared the baked clay from Barnham to the clay from beneath their experimental fires. The grain size and chemical makeup of the clay from the ancient Neanderthal hearth looked almost exactly like “12 or more heating events, each lasting 4 hours at temperatures of 400º Celsius or 600º Celsius,” as Davis and his colleagues wrote.

In other words, the hearth at Barnham hints at the rhythms of daily life for one group of Neanderthals 400,000 years ago. For starters, it seems that they kindled their campfire in the same spot over and over and left it burning for hours at a time. Flakes of flint nearby conjure up images of Neanderthals sitting around the fire, knapping stone tools as they told each other stories long into the night.

Nature, 2025 DOI: 10.1038/s41586-025-09855-6 About DOIs).

Kiona is a freelance science journalist and resident archaeology nerd at Ars Technica.

This is the oldest evidence of people starting fires Read More »

Pompeii construction site confirms recipe for Roman concrete

Archaeology, materials science, Pompeii, Roman concrete, Science / Mike M. / December 9, 2025

Back in 2023, we reported on MIT scientists’ conclusion that the ancient Romans employed “hot mixing” with quicklime, among other strategies, to make their famous concrete, giving the material self-healing functionality. The only snag was that this didn’t match the recipe as described in historical texts. Now the same team is back with a fresh analysis of samples collected from a recently discovered site that confirms the Romans did indeed use hot mixing, according to a new paper published in the journal Nature Communications.

As we’ve reported previously, like today’s Portland cement (a basic ingredient of modern concrete), ancient Roman concrete was basically a mix of a semi-liquid mortar and aggregate. Portland cement is typically made by heating limestone and clay (as well as sandstone, ash, chalk, and iron) in a kiln. The resulting clinker is then ground into a fine powder with just a touch of added gypsum to achieve a smooth, flat surface. But the aggregate used to make Roman concrete was made up of fist-sized pieces of stone or bricks.

In his treatise De architectura (circa 30 CE), the Roman architect and engineer Vitruvius wrote about how to build concrete walls for funerary structures that could endure for a long time without falling into ruin. He recommended the walls be at least two feet thick, made of either “squared red stone or of brick or lava laid in courses.” The brick or volcanic rock aggregate should be bound with mortar composed of hydrated lime and porous fragments of glass and crystals from volcanic eruptions (known as volcanic tephra).

Admir Masic, an environmental engineer at MIT, has studied ancient Roman concrete for several years. For instance, in 2019, Masic helped pioneer a new set of tools for analyzing Roman concrete samples from Privernum at multiple length scales—notably, Raman spectroscopy for chemical profiling and multi-detector energy dispersive spectroscopy (EDS) for phase mapping the material. Masic was also a co-author of a 2021 study analyzing samples of the ancient concrete used to build a 2,000-year-old mausoleum along the Appian Way in Rome known as the Tomb of Caecilia Metella, a noblewoman who lived in the first century CE.

And in 2023, Masic’s group analyzed samples taken from the concrete walls of the Privernum, focusing on strange white mineral chunks known as “lime clasts,” which others had largely dismissed as resulting from subpar raw materials or poor mixing. Masic et al. concluded that was not the case. Rather, the Romans deliberately employed “hot mixing” with quicklime that gave the material self-healing functionality. When cracks begin to form in the concrete, they are more likely to move through the lime clasts. The clasts can then react with water, producing a solution saturated with calcium. That solution can either recrystallize as calcium carbonate to fill the cracks or react with the pozzolanic components to strengthen the composite material.

Pompeii construction site confirms recipe for Roman concrete Read More »

3D model shows small clans created Easter Island statues

Archaeology, easter island, Science / DJ Henderson / December 2, 2025

Credit: ArcGIS

Easter Island is famous for its giant monumental statues, called moai, built some 800 years ago. The volcanic rock used for the moai came from a quarry site called Rano Raraku. Archaeologists have created a high-resolution interactive 3D model of the quarry site to learn more about the processes used to create the moai. (You can explore the full interactive model here.) According to a paper published in the journal PLoS ONE, the model shows that there were numerous independent groups, probably family clans, that created the moai, rather than a centralized management system.

“You can see things that you couldn’t actually see on the ground. You can see tops and sides and all kinds of areas that just would never be able to walk to,” said co-author Carl Lipo of Binghamton University. “We can say, ‘Here, go look at it.’ If you want to see the different kinds of carving, fly around and see stuff there. We’re documenting something that really has needed to be documented, but in a way that’s really comprehensive and shareable.”

Lipo is one of the foremost experts on the Easter Island moai. In October, we reported on Lipo’s experimental confirmation—based on 3D modeling of the physics and new field tests to re-create that motion—that Easter Island’s people transported the statues in a vertical position, with workers using ropes to essentially “walk” the moai onto their platforms. To explain the presence of so many moai, the assumption has been that the island was once home to tens of thousands of people.

Lipo’s latest field trials showed that the “walking” method can be accomplished with far fewer workers: 18 people, four on each lateral rope and 10 on a rear rope, to achieve the side-to-side walking motion. They were efficient enough in coordinating their efforts to move the statue forward 100 meters in just 40 minutes. That’s because the method operates on basic pendulum dynamics, which minimizes friction between the base and the ground. It’s also a technique that exploits the gradual build-up of amplitude, suggesting a sophisticated understanding of resonance principles.

3D model shows small clans created Easter Island statues Read More »

First revealed in spy photos, a Bronze Age city emerges from the steppe

aerial archaeology, ancient cities, ancient people did stuff, Archaeology, bronze age, Kazakhstan, satellite archaeology, Science / Kelly Newman / November 21, 2025

An unexpectedly large city lies in a sea of grass inhabited largely by nomads.

This bronze ax head was found in the western half of Semiyarka. Credit: Radivojevic et al. 2025

Today all that’s left of the ancient city of Semiyarka are a few low earthen mounds and some scattered artifacts, nearly hidden beneath the waving grasses of the Kazakh Steppe, a vast swath of grassland that stretches across northern Kazakhstan and into Russia. But recent surveys and excavations reveal that 3,500 years ago, this empty plain was a bustling city with a thriving metalworking industry, where nomadic herders and traders might have mingled with settled metalworkers and merchants.

Photo of two people standing on a grassy plain under a gray sky — Radivojevic and Lawrence stand on the site of Semiyarka. Credit: Peter J. Brown

Welcome to the City of Seven Ravines

University College of London archaeologist Miljana Radivojevic and her colleagues recently mapped the site with drones and geophysical surveys (like ground-penetrating radar, for example), tracing the layout of a 140-hectare city on the steppe in what’s now Kazakhstan.

The Bronze Age city once boasted rows of houses built on earthworks, a large central building, and a neighborhood of workshops where artisans smelted and cast bronze. From its windswept promontory, it held a commanding view of a narrow point in the Irtysh River valley, a strategic location that may have offered the city “control over movement along the river and valley bottom,” according to Radivojevic and her colleagues. That view inspired archaeologists’ name for the city: Semiyarka, or City of Seven Ravines.

Archaeologists have known about the site since the early 2000s, when the US Department of Defense declassified a set of photographs taken by its Corona spy satellite in 1972, when Kazakhstan was a part of the Soviet Union and the US was eager to see what was happening behind the Iron Curtain. Those photos captured the outlines of Semiyarka’s kilometer-long earthworks, but the recent surveys reveal that the Bronze Age city was much larger and much more interesting than anyone realized.

This 1972 Corona image shows the outlines of Semiyarka’s foundations. Radivojevic et al. 2025

When in doubt, it’s potentially monumental

Most people on the sparsely populated steppe 3,500 years ago stayed on the move, following trade routes or herds of livestock and living in temporary camps or small seasonal villages. If you were a time-traveler looking for ancient cities, the steppe just isn’t where you’d go, and that’s what makes Semiyarka so surprising.

A few groups of people, like the Alekseeva-Sargary, were just beginning to embrace the idea of permanent homes (and their signature style of pottery lies in fragments all over what’s left of Semiyarka). The largest ancient settlements on the steppe covered around 30 hectares—nowhere near the scale of Semiyarka. And Radivojevic and her colleagues say that the layout of the buildings at Semiyarka “is unusual… deviating from more conventional settlement patterns observed in the region.”

What’s left of the city consists mostly of two rows of earthworks: kilometer-long rectangles of earth, piled a meter high. The geophysical survey revealed that “substantial walls, likely of mud-brick, were built along the inside edges of the earthworks, with internal divisions also visible.” In other words, the long mounds of earth were the foundations of rows of buildings with rooms. Based on the artifacts unearthed there, Radivojevic and her colleagues say most of those buildings were probably homes.

The two long earthworks meet at a corner, and just behind that intersection sits a larger mound, about twice the size of any of the individual homes. Based on the faint lines traced by aerial photos and the geophysical survey, it may have had a central courtyard or chamber. In true archaeologist fashion, Durham University archaeologist Dan Lawrence, a coauthor of the recent paper, describes the structure as “potentially monumental,” which means it may have been a space for rituals or community gatherings, or maybe the home of a powerful family.

The city’s layout suggests “a degree of architectural planning,” as Radivojevic and her colleagues put it in their recent paper. The site also yielded evidence of trading with nomadic cultures, as well as bronze production on an industrial scale. Both are things that suggest planning and organization.

“Bronze Age communities here were developing sophisticated, planned settlements similar to those of their contemporaries in more traditionally ‘urban’ parts of the ancient world,” said Lawrence.

Who put the bronze in the Bronze Age? Semiyarka, apparently

Southeast of the mounds, the ground was scattered with broken crucibles, bits of copper and tin ore, and slag (the stuff that’s left over when metal is extracted from ore). That suggested that a lot of smelting and bronze-casting happened in this part of the city. Based on the size of the city and the area apparently set aside for metalworking, Semiyarka boasted what Radivojevic and her colleagues call “a highly-organized, possibly limited or controlled, industry of this sought-after alloy.”

Bronze was part of everyday life for people on the ancient steppes, making up everything from ax heads to jewelry. There’s a reason the period from 2000 BCE to 500 BCE (mileage may vary depending on location) is called the Bronze Age, after all. But the archaeological record has offered almost no evidence of where all those bronze doodads found on the Eurasian steppe were made or who was doing the work of mining, smelting, and casting. That makes Semiyarka a rare and important glimpse into how the Bronze Age was, literally, made.

Radivojevic and her colleagues expected to find traces of earthworks or the buried foundations of mud-brick walls, similar to the earthworks in the northwest, marking the site of a big, centralized bronze-smithing workshop. But the geophysical surveys found no walls at all in the southeastern part of the city.

“This area revealed few features,” they wrote in their recent paper (archaeologists refer to buildings and walls as features), “suggesting that metallurgical production may have been dispersed or occurred in less architecturally formalized spaces.” In other words, the bronzesmiths of ancient Semiyarka seem to have worked in the open air, or in a scattering of smaller, less permanent buildings that didn’t leave a trace behind. But they all seem to have done their work in the same area of the city.

Connections between nomads and city-dwellers

East of the earthworks lies a wide area with no trace of walls or foundations beneath the ground, but with a scattering of ancient artifacts lying half-buried in the grass. The long-forgotten objects may mark the sites of “more ephemeral, perhaps seasonal, occupation,” Radivojevic and her colleagues suggested in their recent paper.

That area makes up a large chunk of the city’s estimated 140 hectares, raising questions about how many people lived here permanently, how many stopped here along trade routes or pastoral migrations, and what their relationship was like.

A few broken potsherds offer evidence that the settled city-dwellers of Semiyarka traded regularly with their more mobile neighbors on the steppe.

Within the city, most of the ceramics match the style of the Alekseevka-Sargary people. But a few of the potsherds unearthed in Semiyarka are clearly the handiwork of nomadic Cherkaskul potters, who lived on this same wide sea of grass from around 1600 BCE to 1250 BCE. It makes sense that they would have traded with the people in the city.

Along the nearby Irtysh River, archaeologists have found faint traces of several small encampments, dating to around the same time as Semiyarka’s heyday, and two burial mounds stand north of the city. Archaeologists will have to dig deeper, literally and figuratively, to piece together how Semiyarka fit into the ancient landscape.

The city has stories to tell, not just about itself but about the whole vast, open steppe and its people.

Antiquity, 2025. DOI: 10.15184/aqy.2025.10244 (About DOIs).

Kiona is a freelance science journalist and resident archaeology nerd at Ars Technica.

First revealed in spy photos, a Bronze Age city emerges from the steppe Read More »

Ancient Egyptians likely used opiates regularly

ancient egypt, Archaeology, chemistry, opiates, pharmacology, Science / Kelly Newman / November 17, 2025

Scientists have found traces of ancient opiates in the residue lining an Egyptian alabaster vase, indicating that opiate use was woven into the fabric of the culture. And the Egyptians didn’t just indulge occasionally: according to a paper published in the Journal of Eastern Mediterranean Archaeology, opiate use may have been a fixture of daily life.

In recent years, archaeologists have been applying the tools of pharmacology to excavated artifacts in collections around the world. As previously reported, there is ample evidence that humans in many cultures throughout history used various hallucinogenic substances in religious ceremonies or shamanic rituals. That includes not just ancient Egypt but also ancient Greek, Vedic, Maya, Inca, and Aztec cultures. The Urarina people who live in the Peruvian Amazon Basin still use a psychoactive brew called ayahuasca in their rituals, and Westerners seeking their own brand of enlightenment have also been known to participate.

For instance, in 2023, David Tanasi, of the University of South Florida, posted a preprint on his preliminary analysis of a ceremonial mug decorated with the head of Bes, a popular deity believed to confer protection on households, especially mothers and children. After collecting sample residues from the vessel, Tanasi applied various techniques—including proteomic and genetic analyses and synchrotron radiation-based Fourier-transform infrared microspectroscopy—to characterize the residues.

Tanasi found traces of Syrian rue, whose seeds are known to have hallucinogenic properties that can induce dream-like visions, per the authors, thanks to its production of the alkaloids harmine and harmaline. There were also traces of blue water lily, which contains a psychoactive alkaloid that acts as a sedative, as well as a fermented alcoholic concoction containing yeasts, wheat, sesame seeds, fruit (possibly grapes), honey, and, um, “human fluids”: possibly breast milk, oral or vaginal mucus, and blood. A follow-up 2024 study confirmed those results and also found traces of pine nuts or Mediterranean pine oil; licorice; tartaric acid salts that were likely part of the aforementioned alcoholic concoction; and traces of spider flowers known to have medicinal properties.

Ancient Egyptians likely used opiates regularly Read More »

Dogs came in a wide range of sizes and shapes long before modern breeds

Archaeology, dog domestication, Dogs, domestication, mesolith, neolithic, paleoarchaeology, Science / Shannon Garcia / November 14, 2025

“The concept of ‘breed’ is very recent and does not apply to the archaeological record,” Evin said. People have, of course, been breeding dogs for particular traits for as long as we’ve had dogs, and tiny lap dogs existed even in ancient Rome. However, it’s unlikely that a Neolithic herder would have described his dog as being a distinct “breed” from his neighbor’s hunting partner, even if they looked quite different. Which, apparently, they did.

A big yellow dog, a little gray dog, and a little white dog — Dogs had about half of their modern diversity (at least in skull shapes and sizes) by the Neolithic. Credit: Kiona Smith

Bones only tell part of the story

“We know from genetic models that domestication should have started during the late Pleistocene,” Evin told Ars. A 2021 study suggested that domestic dogs have been a separate species from wolves for more than 23,000 years. But it took a while for differences to build up.

Evin and her colleagues had access to 17 canine skulls that ranged from 12,700 to 50,000 years old—prior to the end of the ice age—and they all looked enough like modern wolves that, as Evin put it, “for now, we have no evidence to suggest that any of the wolf-like skulls did not belong to wolves or looked different from them.” In other words, if you’re just looking at the skull, it’s hard to tell the earliest dogs from wild wolves.

We have no way to know, of course, what the living dog might have looked like. It’s worth mentioning that Evin and her colleagues found a modern Saint Bernard’s skull that, according to their statistical analysis, looked more wolf-like than dog-like. But even if it’s not offering you a brandy keg, there’s no mistaking a live Saint Bernard, with its droopy jowls and floppy ears, for a wolf.

“Skull shape tells us a lot about function and evolutionary history, but it represents only one aspect of the animal’s appearance. This means that two dogs with very similar skulls could have looked quite different in life,” Evin told Ars. “It’s an important reminder that the archaeological record captures just part of the biological and cultural story.”

And with only bones—and sparse ones, at that—to go on, we may be missing some of the early chapters of dogs’ biological and cultural story. Domestication tends to select the friendliest animals to produce the next generation, and apparently that comes with a particular set of evolutionary side effects, whether you’re studying wolves, foxes, cattle, or pigs. Spots, floppy ears, and curved tails all seem to be part of the genetic package that comes with inter-species friendliness. But none of those traits is visible in the skull.

Dogs came in a wide range of sizes and shapes long before modern breeds Read More »

10,000 generations of hominins used the same stone tools to weather a changing world

Archaeology, australopithecus, hominins, oldowan, paleoarchaeology, Science, stone tools / 9u50fv / November 7, 2025

“This site reveals an extraordinary story of cultural continuity,” said Braun in a recent press release.

When the going gets tough, the tough make tools

Nomorotukunan’s layers of stone tools span the transition from the Pliocene to the Pleistocene, during which Earth’s climate turned gradually cooler and drier after a 2 to 3 million-year warm spell. Pollen and other microscopic traces of plants in the sediment at Nomorotukunan tell the tale: the lakeshore marsh gradually dried up, giving way to arid grassland dotted with shrubs. On a shorter timescale, hominins at Nomorotukunan faced wildfires (based on microcharcoal in the sediments), droughts, and rivers drying up or changing course.

“As vegetation shifted, the toolmaking remained steady,” said National University of Kenya archaeologist Rahab N. Kinyanjui in a recent press release. “This is resilience.”

Making sharp stone tools may have helped generations of hominins survive their changing, drying world. In the warm, humid Pliocene, finding food would have been relatively easy, but as conditions got tougher, hominins probably had to scavenge or dig for their meals. At least one animal bone at Nomorotukunan bears cut marks where long-ago hominins carved up the carcass for meat—something our lineage isn’t really equipped to do with its bare hands and teeth. Tools also would have enabled early hominins to dig up and cut tubers or roots.

It’s fair to assume that sharpened wood sticks probably also played a role in that particular work, but wood doesn’t tend to last as long as stone in the archaeological record, so we can’t say for sure. What is certain are the stone tools and cut bones, which hint at what Utrecht University archaeologist Dan Rolier, a coauthor of the paper, calls “one of our oldest habits: using technology to steady ourselves against change.”

A tale as old as time

Nomorotukunan may hint that Oldowan technology is even older than the earliest tools archaeologists have unearthed so far. The oldest tools unearthed from the deepest layer at Nomorotukunan are the work of skilled flint-knappers who understood where to strike a stone, and at exactly which angle, to flake off the right shape. They also clearly knew how to select the right stones for the job (fine-grained chalcedony for the win, in this case). In other words, these tools weren’t the work of a bunch of hominins who were just figuring out, for the first time, how to bang the rocks together.

10,000 generations of hominins used the same stone tools to weather a changing world Read More »

Wear marks suggest Neanderthals made ocher crayons

ancient people did stuff, Archaeology, Neanderthals, paleoarchaeology, Science, stone tools / Beth Washington / October 31, 2025

“The combination of shaping, wear, and resharpening indicates they were used to draw or mark on soft surfaces,” D’Errico told Ars in an email. “Although the material is too fragile to reveal the specific material on which they were used, such as hide, human skin, or stone, an experimental approach may, in the future, allow us at least to rule out their use on some materials.”

A 73,000-year-old drawing from Blombo Cave in South Africa looks like it was made with tools much like the ocher crayons from Crimea, which means that Neanderthals and Homo sapiens both invented crayons in their own little corners of the world at around the same time.

Image of a reddish-brown rock with a series of lines carved in its surface — The surface of this flat piece of orange ocher was carved over 47,000 years ago, then worn smooth, perhaps by carrying in a bag. Credit: D’Errico et al. 2025

Sometimes you’re the crayon, sometimes you’re the canvas

A third item from Zaskalnaya V is a flat piece of orange ocher. One side is covered with a thin layer of hard, dark rock. But more than 47,000 years ago, someone carefully cut several deep lines, regularly spaced and almost parallel, into its surface. The area of stone between the lines has been worn and polished smooth, suggesting that someone carried it and handled it for years.

“The polish smoothing the engraved lines suggest that the piece was curated, perhaps transported in a bag,” D’Errico told Ars. Whoever carved the lines into the piece of ocher also appears to have been right-handed, based on the angle of the incisions’ walls.

The finds join a host of other evidence of Neanderthal artwork and jewelry, from 57,000-year-old finger marks on a cave wall in France to 114,000-year-old ocher-painted shells in Spain.

“Traditionally viewed as lacking the cognitive flexibility and symbolic capacity of humans, the Neanderthals of Crimea demonstrate the opposite: They engaged in cultural practices that were not merely adaptive but deeply meaningful,” wrote D’Errico and his colleagues. “Their sophisticated use of ocher is one facet of their complex cultural life.”

photo of a reddish-brown pointed rock from four angles — The tip of this red ocher crayon was broken off. Credit: D’Errico et al. 2025

Coloring in some details of Neanderthal culture

It’s hard to say whether the rest of the ocher from the Zaskalnaya sites and other nearby rock shelters meant anything to the Neanderthals beyond the purely pragmatic. However, it’s unlikely that humans (of any stripe) could spend 70,000 years working with vividly colored pigment without developing a sense of aesthetics, assigning some meaning to the colors, or maybe doing both.

Wear marks suggest Neanderthals made ocher crayons Read More »

The first people to set foot in Australia were fossil hunters

aboriginal australians, ancient people did stuff, Archaeology, australia, biological archaeology, Megafauna, megafaunal extinction, Science / 9u50fv / October 23, 2025

I just think they’re neat

Europeans weren’t the first people to collect fossils in Australia.

Several species of short-faced kangaroos, like this one, once lived in Australia. Some stood two meters tall, while others were less than half a meter tall. Credit: By Ghedoghedo – Own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=8398432

Australia’s First Peoples may or may not have hunted the continent’s megafauna to extinction, but they definitely collected fossils.

A team of archaeologists examined the fossilized leg bone of an extinct kangaroo and realized that instead of evidence of butchery, cut marks on the bone reveal an ancient attempt at fossil collecting. That leaves Australia with little evidence of First Peoples hunting or butchering the continent’s extinct megafauna—and reopens the question of whether humans were responsible for the die-off of that continent’s giant Ice Age marsupials.

Fossil hunting in the Ice Age

In the unsolved case of whether humans hunted Australia’s Ice Age megafauna to extinction, the key piece of evidence so far is a tibia (one of the bones of the lower leg) from an extinct short-faced kangaroo. Instead of hopping like their modern relatives, these extinct kangaroos walked on their hind legs, probably placing all their weight on the tips of single hoofed toes. This particular kangaroo wasn’t quite fully grown when it died, which happened sometime between 44,500 and 55,200 years ago, based on uranium-series dating of the thin layer of rock covering most of the fossils in Mammoth Cave (in what’s now Western Australia).

There’s a shallow, angled chunk cut out of the bone near one end. When archaeologists first noticed the cut in 1970 after carefully chipping away the crust of calcium carbonate that had formed over the bone, it looked like evidence that Pleistocene hunters had carved up the kangaroo to eat it. But in their recent paper, University of New South Wales archaeologist Michael Archer and his colleagues say that’s probably not what happened. Instead, they have a stranger idea: “We suggest here that the purpose of this effort may have been the retrieval of the fossils from the bone-rich late-Pleistocene deposit in Mammoth Cave after its discovery by First Peoples,” they wrote in their recent paper.

a photo of a fossil bone with a shallow chunk cut out of it — This close-up image shows the cut kangaroo bone and a micro-CT image of the surfaces of the cut. Credit: Archer et al. 2025

The world used to be so much weirder

Based on the available archaeological evidence, it looks like people first set foot on Australia sometime around 65,000 years ago. At the time, the continent was home to a bizarre array of giant marsupials, as well as flightless birds even bigger and scarier than today’s emus and cassowaries. For the next 20,000 years, Australia’s First Peoples shared the landscape with short-faced kangaroos; Zygomaturus trilobus, a hulking 500-kilogram marsupial that looked a little like a rhinoceros; and Diprotodon optatum, the largest marsupial that ever lived: a 3,000-kilogram behemoth that roamed in huge herds (picture a bear about the size of a bison with a woodchuck’s face).

These species died out sometime around 45,000 or 40,000 years ago; today, they live on in ancient rock art and stories, some of which seem to describe people interacting with now-extinct species.

Since they had shared the continent with humans for at least 20,000 years at that point, it doesn’t seem that the sudden arrival of humans caused an immediate mass extinction. But it’s possible that by hunting or even setting controlled fires, people may have put just enough strain on these megafauna species to make them vulnerable enough for the next climate upheaval to finish them off.

In some parts of the world, there’s direct evidence that Pleistocene people hunted or scavenged meat from the remains of now-extinct megafauna. Elsewhere, archaeologists are still debating whether humans, the inexorable end of the last Ice Age, or some combination of the two killed off the world’s great Ice Age giants. The interaction between people and their local ecosystems looked (and still looks) different everywhere, depending on culture, environment, and a host of other factors.

The jury is still out on what killed the megafauna in Australia because the evidence we need either hasn’t survived the intervening millennia or still lies buried somewhere, waiting to be found and studied. For decades, the one clear bit of evidence has seemed to be the Mammoth Cave short-faced kangaroo tibia. But Archer and his colleagues argue that even that isn’t a smoking gun.

An man in khakis and a dark blue shirt studies a cave wall. — An archaeologist examines a fossil deposit in the wall of Mammoth Cave, in Western Australia. 50,000 years ago, one of the earliest people on the continent may also have stood here contemplating the fossils. Credit: Archer et al. 2025

Evidence of rock collecting, not butchery

For one thing, the researchers argue that the kangaroo had been dead for a very long time when the cut was made. Nine long, thin cracks run along the length of the tibia, formed when the bone dried and shrank. And in the cut section, there’s a short crack running across the width of the bone—but it stops at either end when it meets the long cracks from the bone’s drying. That suggests the bone had already dried and shrunk, leaving those long cracks before the cut was made. It may have just been a very old bone, or it may have already begun to fossilize, but the meat would have been long gone, leaving behind a bone sticking out of the cave wall.

Since there’s no mark or dent on the opposite side of the bone from the cut (which would have happened if it were lying on the ground being butchered), it was probably sticking out of the fossil bed in the cave wall when someone came along and tried to cut it free. And since a crust of calcium carbonate had time to form over the cut (it covers most of the fossils in Mammoth Cave like a rocky burial shroud), that must have happened at least 44,000 years ago.

That leaves us with an interesting mental image: a member of one of Australia’s First Peoples, 45,000 years ago, exploring a cave filled with the bones of fantastical, long-dead animals. This ancient caver finds a bone sticking out from the cave wall and tries to hack the protruding end free—twice, from different angles—before giving up and leaving it in place.

People have always collected cool rocks

We can’t know for sure why this long-ago person wanted the bone in the first place. (Did it have a religious purpose? Might it have made a good tool? Was it just a cool souvenir?) We also don’t know why they gave up their attempt. But if Archer and his colleagues are right, the bone leaves Australia without any clear evidence that ancient people hunted—or even scavenged food from the remains of—extinct Pleistocene megafauna like short-faced kangaroos.

“This is not to say that it did not happen, just that there is now no hard evidence to support that it did,” Archer and his colleagues wrote in their recent paper. We don’t yet know exactly how Australia’s First Peoples interacted with these species.

But whether Archer and his colleagues are correct in their analysis of this particular kangaroo bone or not, humans around the world have been picking up fossils for at least tens of thousands of years. There’s evidence that people in Australia have collected and traded the fossils of extinct animals for pretty much as long as people have been in Australia, including everything from trilobites to Zygomaturus teeth and the jawbones of other extinct marsupials.

“What we can conclude,” Archer and his colleagues wrote, “is that the first people in Australia who demonstrated a keen interest in and collected fossils were First Peoples, probably thousands of years before Europeans set foot on that continent.”

Royal Society Open Science, 2025. DOI: 10.1098/rsos.250078 (About DOIs).

Kiona is a freelance science journalist and resident archaeology nerd at Ars Technica.

The first people to set foot in Australia were fossil hunters Read More »

Lead poisoning has been a feature of our evolution

anthropology, Archaeology, australopithecus, hominins, lead poisoning, Neanderthals, paleoanthropology, Science / Mike M. / October 17, 2025

A recent study found lead in teeth from 2 million-year-old hominin fossils.

Our hominid ancestors faced a Pleistocene world full of dangers—and apparently one of those dangers was lead poisoning.

Lead exposure sounds like a modern problem, at least if you define “modern” the way a paleoanthropologist might: a time that started a few thousand years ago with ancient Roman silver smelting and lead pipes. According to a recent study, however, lead is a much more ancient nemesis, one that predates not just the Romans but the existence of our genus Homo. Paleoanthropologist Renaud Joannes-Boyau of Australia’s Southern Cross University and his colleagues found evidence of exposure to dangerous amounts of lead in the teeth of fossil apes and hominins dating back almost 2 million years. And somewhat controversially, they suggest that the toxic element’s pervasiveness may have helped shape our evolutionary history.

The skull of an early hominid, aged to a dark brown color. The skull is fragmentary, but the fragments are held in the appropriate locations by an underlying beige material. — The skull of an early hominid. Credit: Einsamer Schütze / Wikimedia

The Romans didn’t invent lead poisoning

Joannes-Boyau and his colleagues took tiny samples of preserved enamel and dentin from the teeth of 51 fossils. In most of those teeth, the paleoanthropologists found evidence that these apes and hominins had been exposed to lead—sometimes in dangerous quantities—fairly often during their early years.

Tooth enamel forms in thin layers, a little like tree rings, during the first six or so years of a person’s life. The teeth in your mouth right now (and of which you are now uncomfortably aware; you’re welcome) are a chemical and physical record of your childhood health—including, perhaps, whether you liked to snack on lead paint chips. Bands of lead-tainted tooth enamel suggest that a person had a lot of lead in their bloodstream during the year that layer of enamel was forming (in this case, “a lot” means an amount measurable in parts per million).

In 71 percent of the hominin teeth that Joannes-Boyau and his colleagues sampled, dark bands of lead in the tooth enamel showed “clear signs of episodic lead exposure” during the crucial early childhood years. Those included teeth from 100,000-year-old members of our own species found in China and 250,000-year-old French Neanderthals. They also included much earlier hominins who lived between 1 and 2 million years ago in South Africa: early members of our genus Homo, along with our relatives Australopithecus africanus and Paranthropus robustus. Lead exposure, it turns out, is a very ancient problem.

Living in a dangerous world

This study isn’t the first evidence that ancient hominins dealt with lead in their environments. Two Neanderthals living 250,000 years ago in France experienced lead exposure as young children, according to a 2018 study. At the time, they were the oldest known examples of lead exposure (and they’re included in Joannes-Boyau and his colleagues’ recent study).

Until a few thousand years ago, no one was smelting silver, plumbing bathhouses, or releasing lead fumes in car exhaust. So how were our hominin ancestors exposed to the toxic element? Another study, published in 2015, showed that the Spanish caves occupied by other groups of Neanderthals contained enough heavy metals, including lead, to “meet the present-day standards of ‘contaminated soil.’”

Today, we mostly think of lead in terms of human-made pollution, so it’s easy to forget that it’s also found naturally in bedrock and soil. If that weren’t the case, archaeologists couldn’t use lead isotope ratios to tell where certain artifacts were made. And some places—and some types of rock—have higher lead concentrations than others. Several common minerals contain lead compounds, including galena or lead sulfide. And the kind of lead exposure documented in Joannes-Boyau and his colleagues’ study would have happened at an age when little hominins were very prone to putting rocks, cave dirt, and other random objects in their mouths.

Some of the fossils from the Queque cave system in China, which included a 1.8 million-year-old extinct gorilla-like ape called Gigantopithecus blacki, had lead levels higher than 50 parts per million, which Joannes-Boyau and his colleagues describe as “a substantial level of lead that could have triggered some developmental, health, and perhaps social impairments.”

Even for ancient hominins who weren’t living in caves full of lead-rich minerals, wildfires, or volcanic eruptions can also release lead particles into the air, and erosion or flooding can sweep buried lead-rich rock or sediment into water sources. If you’re an Australopithecine living upstream of a lead-rich mica outcropping, for example, erosion might sprinkle poison into your drinking water—or the drinking water of the gazelle you eat or the root system of the bush you get those tasty berries from… .

Our world is full of poisons. Modern humans may have made a habit of digging them up and pumping them into the air, but they’ve always been lying in wait for the unwary.

screenshot from the app — Cubic crystals of the lead-sulfide mineral galena.

Digging into the details

Joannes-Boyau and his colleagues sampled the teeth of several hominin species from South Africa, all unearthed from cave systems just a few kilometers apart. All of them walked the area known as Cradle of Humankind within a few hundred thousand years of each other (at most), and they would have shared a very similar environment. But they also would have had very different diets and ways of life, and that’s reflected in their wildly different exposures to lead.

A. africanus had the highest exposure levels, while P. robustus had signs of infrequent, very slight exposures (with Homo somewhere in between the two). Joannes-Boyau and his colleagues chalk the difference up to the species’ different diets and ecological niches.

“The different patterns of lead exposure could suggest that P. robustus lead bands were the result of acute exposure (e.g., wild forest fire),” Joannes-Boyau and his colleagues wrote, “while for the other two species, known to have a more varied diet, lead bands may be due to more frequent, seasonal, and higher lead concentration through bioaccumulation processes in the food chain.”

Did lead exposure affect our evolution?

Given their evidence that humans and their ancestors have regularly been exposed to lead, the team looked into whether this might have influenced human evolution. In doing so, they focused on a gene called NOVA1, which has been linked to both brain development and the response to lead exposure. The results were quite a bit short of decisive; you can think of things as remaining within the realm of a provocative hypothesis.

The NOVA1 gene encodes a protein that influences the processing of messenger RNAs, allowing it to control the production of closely related variants of a single gene. It’s notable for a number of reasons. One is its role in brain development; mice without a working copy of NOVA1 die shortly after birth due to defects in muscle control. Its activity is also altered following exposure to lead.

But perhaps its most interesting feature is that modern humans have a version of the gene that differs by a single amino acid from the version found in all other primates, including our closest relatives, the Denisovans and Neanderthals. This raises the prospect that the difference is significant from an evolutionary perspective. Altering the mouse version so that it is identical to the one found in modern humans does alter the vocal behavior of these mice.

But work with human stem cells has produced mixed results. One group, led by one of the researchers involved in this work, suggested that stem cells carrying the ancestral form of the protein behaved differently from those carrying the modern human version. But others have been unable to replicate those results.

Regardless of that bit of confusion, the researchers used the same system, culturing stem cells with the modern human and ancestral versions of the protein. These clusters of cells (called organoids) were grown in media containing two different concentrations of lead, and changes in gene activity and protein production were examined. The researchers found changes, but the significance isn’t entirely clear. There were differences between the cells with the two versions of the gene, even without any lead present. Adding lead could produce additional changes, but some of those were partially reversed if more lead was added. And none of those changes were clearly related either to a response to lead or the developmental defects it can produce.

The relevance of these changes isn’t obvious, either, as stem cell cultures tend to reflect early neural development while the lead exposure found in the fossilized remains is due to exposure during the first few years of life.

So there isn’t any clear evidence that the variant found in modern humans protects individuals who are exposed to lead, much less that it was selected by evolution for that function. And given the widespread exposure seen in this work, it seems like all of our relatives—including some we know modern humans interbred with—would also have benefited from this variant if it was protective.

Science Advances, 2025. DOI: 10.1126/sciadv.adr1524 (About DOIs).

Kiona is a freelance science journalist and resident archaeology nerd at Ars Technica.

Lead poisoning has been a feature of our evolution Read More »

How Easter Island’s giant statues “walked” to their final platforms

anthropology, Archaeology, easter island, experimental archaeology, Physics, rapa nui, Science / DJ Henderson / October 9, 2025

Workers with ropes could make the moai “walk” in zig-zag motion along roads tailor-made for the purpose.

Easter Island is famous for its giant monumental statues, called moai, built some 800 years ago and typically mounted on platforms called ahu. Scholars have puzzled over the moai on Easter Island for decades, pondering their cultural significance, as well as how a Stone Age culture managed to carve and transport statues weighing as much as 92 tons. One hypothesis, championed by archaeologist Carl Lipo of Binghamton University, among others, is that the statues were transported in a vertical position, with workers using ropes to essentially “walk” the moai onto their platforms.

The oral traditions of the people of Rapa Nui certainly include references to the moai “walking” from the quarry to their platforms, such as a song that tells of an early ancestor who made the statues walk. While there have been rudimentary field tests showing it might have been possible, the hypothesis has also generated a fair amount of criticism. So Lipo has co-authored a new paper published in the Journal of Archaeological Science offering fresh experimental evidence of “walking” moai, based on 3D modeling of the physics and new field tests to recreate that motion.

The first Europeans arrived in the 17th century and found only a few thousand inhabitants on the tiny island (just 14 by 7 miles across) thousands of miles away from any other land. In order to explain the presence of so many moai, the assumption has been that the island was once home to tens of thousands of people. But Lipo thought perhaps the feat could be accomplished with fewer workers. In 2012, Lipo and his colleague, Terry Hunt of the University of Arizona, showed that you could transport a 10-foot, 5-ton moai a few hundred yards with just 18 people and three strong ropes by employing a rocking motion.

In 2018, Lipo followed up with an intriguing hypothesis for how the islanders placed red hats on top of some moai; those can weigh up to 13 tons. He suggested the inhabitants used ropes to roll the hats up a ramp. Lipo and his team later concluded (based on quantitative spatial modeling) that the islanders likely chose the statues’ locations based on the availability of fresh water sources, per a 2019 paper in PLOS One.

The 2012 experiment demonstrated proof of principle, so why is Lipo revisiting it now? “I always felt that the [original] experiment was disconnected to some degree of theory—that we didn’t have particular expectations about numbers of people, rate of transport, road slope that could be walked, and so on,” Lipo told Ars. There were also time constraints because the attempt was being filmed for a NOVA documentary.

“That experiment was basically a test to see if we could make it happen or not,” he explained. “Fortunately, we did, and our joy in doing so is pretty well represented by our hoots and hollers when it started to walk with such limited efforts. Some of the limitation of the work was driven by the nature of TV. [The film crew] just wanted us—in just a day and half—to give it a shot. It was 4: 30 on the last day when it finally worked so we really didn’t get a lot of time to explore variability. We also didn’t have any particular predictions to test.”

Example of a road moai that fell and was abandoned after an attempt to re-erect it by excavating under its base, leaving it partially buried at an angle. Credit: Carl Lipo

This time around, “We wanted to explore a bit of the physics: to show that what we did was pretty easily predicted by the physical properties of the moai—its shape, size, height, number of people on ropes, etc.—and that our success in terms of team size and rate of walking was consistent with predictions,” said Lipo. “This enables us to address one of the central critiques that always comes up: ‘Well, you did this with a 5-ton version that was 10 feet tall, but it would never work with a 30-ft-tall version that weighs 30 tons or more.'”

All about that base

You can have ahu (platforms) without moai (statues) and moai without ahu, usually along the roads leading to ahu; they were likely being transported and never got to their destination. Lipo and Hunt have amassed a database of 962 moai across the island, compiled through field surveys and photogrammetric documentation. They were particularly interested in 62 statues located along ancient transport roads that seemed to have been abandoned where they fell.

Their analysis revealed that these road moai had significantly wider bases relative to shoulder width, compared to statues mounted on platforms. This creates a stable foundation that lowers the center of mass so that the statue is more conducive to the side-to-side motion of walking transport without toppling over. Platform statues, by contrast, have shoulders wider than the base for a more top-heavy configuration.

The road moai also have a consistent and pronounced forward lean of between 6 degrees to 15 degrees from the vertical position, which moves the center of mass close to or just beyond the base’s front edge. Lipo and Hunt think this was due to careful engineering, not coincidence. It’s not conducive to stable vertical display but it is a boon during walking transport, because the forward lean causes the statue to fall forward when tilted laterally, with the rounded front base edge serving as a crucial pivot point. So every lateral rocking motion results in a forward “step.”

Per the authors, there is strong archaeological evidence that carvers modified the statues once they arrived at their platform destinations, modifying the base to eliminate the lean by removing material from the front. This shifted the center of mass over the base area for a stable upright position. The road moai even lack the carved eye sockets designed to hold white coral eyes with obsidian or red scoria for pupils—a final post-transport step once the statues had been mounted on their platforms.

Based on 3D modeling, Lipo and his team created a precisely scaled replica of one of the road moai, weighing 4.35 metric tons with the same proportions and mass distribution of the original statue. “Of course, we’d love to build a 30-foot-tall version, but the physical impossibility of doing so makes it a challenging task, nor is it entirely necessary,” said Lipo. “Through physics, we can now predict how many people it would take and how it would be done. That is key.”

Lipo's team created 3D models of moai to determine the unique characteristics that made them able to be — Lipo’s team created 3D models of moai to determine the unique characteristics that made them able to be “walked” across Rapa Nui. Credit: Carl Lipo

The new field trials required 18 people, four on each lateral rope and 10 on a rear rope, to achieve the side-to-side walking motion, and they were efficient enough in coordinating their efforts to move the statue forward 100 meters in just 40 minutes. That’s because the method operates on basic pendulum dynamics, per the authors, which minimizes friction between the base and the ground. It’s also a technique that exploits the gradual build-up of amplitude, which “suggests a sophisticated understanding of resonance principles,” Lipo and Hunt wrote.

So the actual statues could have been moved several kilometers over the course of weeks with only modest-sized crews of between 20-50 people, i.e., roughly the size of an extended family or “small lineage group” on Easter Island. Once the crew gets the statue rocking side to side—which can require between 15 to 60 people, depending on the size and weight of the moai—the resulting oscillation only needs minimal energy input from a smaller team of rope handlers to maintain that motion. They mostly provide guidance.

Lipo was not the first to test the walking hypothesis. Earlier work includes that of Czech experimental archaeologist Pavel Pavel, who conducted similar practical experiments on Easter Island in the 1980s after being inspired by Thor Heyerdahl’s Kon Tiki. (Heyerdahl even participated in the experiments.) Pavel’s team was able to demonstrate a kind of “shuffling” motion, and he concluded that just 16 men and one leader were sufficient to transport the statues.

Per Lipo and Hunt, Pavel’s demonstration didn’t result in broad acceptance of the walking hypothesis because it still required a huge amount of effort to tilt the statue, producing more of a twisting motion rather than efficient forward movement. This would only have moved a large statue 100 meters a day under ideal conditions. The base was also likely to be damaged from friction with the ground. Lipo and Hunt maintain this is because Pavel (and others who later tried to reproduce his efforts) used the wrong form of moai for those earlier field tests: those erected on the platforms, already modified for vertical stability and permanent display, and not the road moai with shapes more conducive to vertical transport.

“Pavel deserves recognition for taking oral traditions seriously and challenging the dominant assumption of horizontal transport, a move that invited ridicule from established scholars,” Lipo and Hunt wrote. “His experiments suggested that vertical transport was feasible and consistent with cultural memory. Our contribution builds on this by showing that ancestral engineers intentionally designed statues for walking. Those statues were later modified to stand erect on ceremonial platforms, a transformation that effectively erased the morphological features essential for movement.”

The evidence of the roadways

Lipo and Hunt also analyzed the roadways, noting that these ancient roadbeds had concave cross sections that would have been problematic for moving the statues horizontally using wooden rollers or frames perpendicular to those roads. But that concave shape would help constrain rocking movement during vertical transport. And the moai roads were remarkably level with slopes of, on average, 2–3 percent. For the occasional steeper slopes, such as walking a moai up a ramp to the top of an ahu, Lipo and Hunt’s field experiments showed that these could be navigated successfully through controlled stepping.

Furthermore, the distribution pattern of the roadways is consistent with the road moai being left due to mechanical failure. “Arguments that the moai were placed ceremonially in preparation for quarrying have become more common,” said Lipo. “The algorithm there is to claim that positions are ritual, without presenting anything that is falsifiable. There is no reason why the places the statues fell due to mechanical reasons couldn’t later become ‘ritual,’ in the same way that everything on the island could be claimed to be ritual—a circular argument. But to argue that they were placed there purposefully for ritual purposes demands framing the explanation in a way that is falsifiable.”

Schematic representation of the moai transport method using coordinated rope pulling to achieve a “walking” motion. Credit: Carl Lipo and Terry Hunt, 2025

“The only line of evidence that is presented in this way is the presence of ‘platforms’ that were found beneath the base of one moai, which is indeed intriguing,” Lipo continued. “However, those platforms can be explained in other ways, given that the moai certainly weren’t moved from the quarry to the ahu in one single event. They were paused along the way, as is clear from the fact that the roads appear to have been constructed in segments with different features. Their construction appears to be part of the overall transport process.”

Lipo’s work has received a fair share of criticism from other scholars over the years, and his and Hunt’s paper includes a substantial section rebutting the most common of those critiques. “Archaeologists tend to reject (in practice) the idea that the discipline can construct cumulative knowledge,” said Lipo. “In the case of moai transport, we’ve strived to assemble as much empirical evidence as possible and have forwarded an explanation that best accounts for what we can observe. Challenges to these ideas, however, do not come from additional studies with new data but rather just new assertions.”

“This leads the public to believe that we (as a discipline) can never really figure anything out and are always going to be a speculative enterprise, spinning yarns and arguing with each other,” Lipo continued. “With the erosion of trust in science, this is fairly catastrophic to archaeology as a whole but also the whole scientific enterprise. Summarizing the results in the way we do here is an attempt to point out that we can build falsifiable accounts and can make contributions to cumulative knowledge that have empirical consequences—even with something as remarkable as the transport of moai.”

Experimental archaeology is a relatively new field that some believe could be the future of archaeology. “I think experimental archaeology has potential when it’s tied to physics and chemistry,” said Lipo. “It’s not just recreating something and then arguing it was done in the same way in the past. Physics and chemistry are our time machines, allowing us to explain why things are the way they are in the present in terms of the events that occurred in the past. The more we can link the theory needed to explain the present, the better we can explain the past.”

DOI: Journal of Archaeological Science, 2025. 10.1016/j.jas.2025.106383 (About DOIs).

Jennifer is a senior writer at Ars Technica with a particular focus on where science meets culture, covering everything from physics and related interdisciplinary topics to her favorite films and TV series. Jennifer lives in Baltimore with her spouse, physicist Sean M. Carroll, and their two cats, Ariel and Caliban.

How Easter Island’s giant statues “walked” to their final platforms Read More »

Here’s the real reason Endurance sank

Archaeology, Endurance shipwreck, maritime history, Science, Sir Ernest Shackleton / 9u50fv / October 6, 2025

The ship wasn’t designed to withstand the powerful ice compression forces—and Shackleton knew it.

The Endurance, frozen and keeled over in the ice of the Weddell Sea. Credit: BF/Frank Hurley

In 1915, intrepid British explorer Sir Ernest Shackleton and his crew were stranded for months in the Antarctic after their ship, Endurance, was trapped by pack ice, eventually sinking into the freezing depths of the Weddell Sea. Miraculously, the entire crew survived. The prevailing popular narrative surrounding the famous voyage features two key assumptions: that Endurance was the strongest polar ship of its time, and that the ship ultimately sank after ice tore away the rudder.

However, a fresh analysis reveals that Endurance would have sunk even with an intact rudder; it was crushed by the cumulative compressive forces of the Antarctic ice with no single cause for the sinking. Furthermore, the ship wasn’t designed to withstand those forces, and Shackleton was likely well aware of that fact, according to a new paper published in the journal Polar Record. Yet he chose to embark on the risky voyage anyway.

Author Jukka Tuhkuri of Aalto University is a polar explorer and one of the leading researchers on ice worldwide. He was among the scientists on the Endurance22 mission that discovered the Endurance shipwreck in 2022, documented in a 2024 National Geographic documentary. The ship was in pristine condition partly because of the lack of wood-eating microbes in those waters. In fact, the Endurance22 expedition’s exploration director, Mensun Bound, told The New York Times at the time that the shipwreck was the finest example he’s ever seen; Endurance was “in a brilliant state of preservation.”

As previously reported, Endurance set sail from Plymouth on August 6, 1914, with Shackleton joining his crew in Buenos Aires, Argentina. By the time they reached the Weddell Sea in January 1915, accumulating pack ice and strong gales slowed progress to a crawl. Endurance became completely icebound on January 24, and by mid-February, Shackleton ordered the boilers to be shut off so that the ship would drift with the ice until the weather warmed sufficiently for the pack to break up. It would be a long wait. For 10 months, the crew endured the freezing conditions. In August, ice floes pressed into the ship with such force that the ship’s decks buckled.

The ship’s structure nonetheless remained intact, but by October 25, Shackleton realized Endurance was doomed. He and his men opted to camp out on the ice some two miles (3.2 km) away, taking as many supplies as they could with them. Compacted ice and snow continued to fill the ship until a pressure wave hit on November 13, crushing the bow and splitting the main mast—all of which was captured on camera by crew photographer Frank Hurley. Another pressure wave hit in the late afternoon on November 21, lifting the ship’s stern. The ice floes parted just long enough for Endurance to finally sink into the ocean before closing again to erase any trace of the wreckage.

Once the wreck had been found, the team recorded as much as they could with high-resolution cameras and other instruments. Vasarhelyi, particularly, noted the technical challenge of deploying a remote digital 4K camera with lighting at 9,800 feet underwater, and the first deployment at that depth of photogrammetric and laser technology. This resulted in a millimeter-scale digital reconstruction of the entire shipwreck to enable close study of the finer details.

Challenging the narrative

The ice and wave tank at Aalto University. Credit: Aalto University

It was shortly after the Endurance22 mission found the shipwreck that Tuhkuri realized that there had never been a thorough structural analysis conducted of the vessel to confirm the popular narrative. Was Endurance truly the strongest polar ship of that time, and was a broken rudder the actual cause of the sinking? He set about conducting his own investigation to find out, analyzing Shackleton’s diaries and personal correspondence, as well as the diaries and correspondence of several Endurance crew members.

Tuhkuri also conducted a naval architectural analysis of the vessel under the conditions of compressive ice, which had never been done before. He then compared those results with the underwater images of the Endurance shipwreck. He also looked at comparable wooden polar expedition ships and steel icebreakers built in the late 1800s and early 1900s.

Endurance was originally named Polaris; Shackleton renamed it when he purchased the ship in 1914 for his doomed expedition. Per Tuhkuri, the ship had a lower (tween) deck, a main deck, and a short bridge deck above them that stopped at the machine room in order to make space for the steam engine and boiler. There were no beams in the machine room area, nor any reinforcing diagonal beams, which weakened this significant part of the ship’s hull.

This is because Endurance was originally built for polar tourism and for hunting polar bears and walruses in the Arctic; at the ice edge, ships only needed sufficiently strong planking and frames to withstand the occasional collision from ice floes. However, “In pack ice conditions, where compression from the ice needs to be taken into account, deck beams become of key importance,” Tuhkuri wrote. “It is the deck beams that keep the two ship sides apart and maintain the shape of a ship. Without strong enough deck beams, a vessel gets crushed by compressive ice, more or less irrespective of the thickness of planking and frames.”

The Endurance was nonetheless sturdy enough to withstand five serious ice compression events before her final sinking. On April 4, 1915, one of the scientists on board reported hearing loud rumbling noises from a 3-meter-high ice ridge that formed near the ship, causing the ship to vibrate. Tuhkuri believes this was due to a “compressive failure process” as ice crushed against the hull. On July 14, a violent snowstorm hit, and crew members could hear the ice breaking beneath the ship. The ice ridges that formed over the next few days were sufficiently concerning that Shackleton instituted four-hour watches on deck and insisted on having everything packed in case they had to abandon ship.

Crushed by the ice

Idealized cross sections of early Antarctic ships. Endurance was type (a); Fram and Deutschland were type (b). — Idealized cross sections of early Antarctic ships. *Endurance* was type (a); *Deutschland* was type (b). Credit: J. Tuhkuri, 2025

On August 1, an ice floe fractured and grinding noises were heard beneath the ship as the floe piled underneath it, lifting Endurance and causing her to first heel starboard and then heel to port, as several deck beams began to buckle. Similar compression events kept happening until there was a sudden escalation on September 30. The hull began vibrating hard enough to shake the whole rigging as even more ice crushed against the hull. Even the linoleum on the floors buckled; Harry McNish wrote in his diary that it looked like Endurance “was going to pieces.”

Yet another ice compression event occurred on October 17, pushing the vessel one meter into the air as the iron plates on the engine room’s floor buckled and slid over each other. Ship scientist Reginald James wrote that “for a time things were not good as the pressure was mostly along the region of the engine room where there are no beams of any strength,” while Captain Worsley described the engine room as “the weakest part of the ship.”

By the afternoon, Endurance was heeled almost 30 degrees to port, so much so that the keel was visible from the starboard side, per Tuhkuri, although the ice started to fracture in the evening so that the ship could shift upright again. The crew finally abandoned ship on October 27 after an even more severe compression event hit a few days before. Endurance finally sank below the ice on November 21.

Tuhkuri’s analysis of the structural damage to Endurance revealed that the rudder and the stern post were indeed torn off, confirmed by crew correspondence and diaries and by the underwater images taken of the wreck. The keel was also ripped off, with McNish noting in his diary that the ship broke into two halves as a result. The underwater images are less clear on this point, but Tuhkuri writes that there is something “some distance forward from the rudder, on the port side” that “could be the end of a displaced part of the keel sticking up from under the ship.”

All the diaries mentioned the buckling and breaking of deck beams, and there was much structural damage to the ship’s sides; for instance, Worsley writes of “great spikes of ice… forcing their way through the ship’s sides.” There are no visible holes in the wreck’s sides in the underwater images, but Tuhkuri posits that the damage is likely buried in the mud on the sea bed, given that by late October, Endurance “was heavily listed and the bottom was exposed.”

Jukka Tuhkari on the polar ice — Jukka Tuhkuri on the ice. Credit: Aalto University

Based on his analysis, Tuhkuri concluded that the rudder wasn’t the sole or primary reason for the ship’s sinking. “Endurance would have sunk even if it did not have a rudder at all,” Tuhkuri wrote; it was crushed by the ice, with no single reason for its eventual sinking. Shackleton himself described the process as ice floes “simply annihilating the ship.”

Perhaps the most surprising finding is that Shackleton knew of Endurance‘s structural shortcomings even before undertaking the voyage. Per Tuhkuri, the devastating effects of compressive ice on ships were known to shipbuilders in the early 1900s. An early Swedish expedition was forced to abandon its ship Antarctic in February 1903 when it became trapped in the ice. Things progressed much like Endurance: the ice lifted Antarctic up so that the ship heeled over, with ice-crushed sides, buckling beams, broken planking, and a damaged rudder and stern post. The final sinking occurred when an advancing ice floe ripped off the keel.

Shackleton knew of Antarctic‘s fate and had even been involved in the rescue operation. He also helped Wilhelm Filchner make final preparations for Filchner’s 1911–1913 polar expedition with a ship named Deutschland; he even advised his colleague to strengthen the ship’s hull by adding diagonal beams, the better to withstand the Weddell Sea ice. Filchner did so, and as a result, Deutschland survived eight months of being trapped in compressive ice until the ship was finally able to break free and sail home. (It took a torpedo attack in 1917 to sink the good ship Deutschland.)

The same shipyard that modified Deutschland had also just signed a contract to build Endurance (then called Polaris). So both Shackleton and the shipbuilders knew how destructive compressive ice could be and how to bolster a ship against it. Yet Endurance was not outfitted with diagonal beams to strengthen its hull. And knowing this, Shackleton bought Endurance anyway for his 1914–1915 voyage. In a 1914 letter to his wife, he even compared the strength of its construction unfavorably with that of the Nimrod, the ship he used for his 1907–1909 expedition. So Shackleton had to know he was taking a big risk.

“Even simple structural analysis shows that the ship was not designed for the compressive pack ice conditions that eventually sank it,” said Tuhkuri. “The danger of moving ice and compressive loads—and how to design a ship for such conditions—was well understood before the ship sailed south. So we really have to wonder why Shackleton chose a vessel that was not strengthened for compressive ice. We can speculate about financial pressures or time constraints, but the truth is, we may never know. At least we now have more concrete findings to flesh out the stories.”

Polar Record, 2025. DOI: 10.1017/S0032247425100090 (About DOIs).

Here’s the real reason Endurance sank Read More »