Bear remains challenge long-held theory on farming’s arrival in Ireland and Great Britain

 

New research led by University College Dublin has rewritten a key chapter in Irish prehistory, revealing that bones long thought to mark the beginning of farming in Ireland belong to bear and wild boar, not cattle.

For more than 30 years, animal remains discovered during excavations at Ferriter's Cove, a small bay on the Dingle Peninsula in County Kerry, and dated to the end of the Mesolithic period (8000-4000 BCE) have been cited as proof that before agriculture became established in Ireland, there was contact between its Mesolithic hunter-gatherers and Europe's Neolithic farming communities.

Believed to be bone fragments belonging to cattle, the find is considered to be the earliest evidence for the presence of domesticated farm animals for the islands of Ireland and Britain.

Now, UCD researchers have shown the famous bones were never cattle at all but belonged to a bear and wild boar.

Detailed in the latest edition of PAST, the newsletter of the Prehistoric Society, the discovery removes one of the most significant pieces of evidence for when agriculture developed in Ireland or Great Britain, and likely forces a rethink of when and how their communities moved from Mesolithic hunter-gatherer lifestyles to Neolithic farming societies.

The new findings are part of a Research Ireland-funded postdoctoral project at the UCD School of Archaeology, led by Dr Martin Moucheron, under the mentorship of Professor Graeme Warren, which is re-examining important Mesolithic archaeological sites using modern scientific techniques.

The new research is part of a Research Ireland-funded postdoctoral project at the UCD School of Archaeology, led by Dr Martin Moucheron, under the mentorship of Professor Graeme Warren, which is re-examining important Mesolithic archaeological sites using modern scientific techniques.

“For at least four millennia hunting and gathering people lived on the island, and there is a common conception that they left little trace and that we know very little about them - unlike the megaliths of Neolithic farmers, who are portrayed in ways that feel very familiar in Ireland,” said Dr Moucheron.

“But there is much we can understand about Mesolithic people just by going back to the sites and material we have, and by looking at them with new eyes and new techniques - and an open mind.”

Ferriter's Cove has occupied a central place in debates about Ireland's prehistoric past since excavations in the 1980s and 1990s uncovered several bone fragments initially identified as domesticated cattle.

The presence of such remains, the so-called "Kerry Cow", contradicted existing theories of the Mesolithic–Neolithic transition in Ireland, and, ever since, have been cited as evidence that its Mesolithic communities had established links with early farmers arriving from Continental Europe.

In collaboration with Dr(s) Benjamin Gearey, Barra Ó Donnabháin, and Margaret McCarthy, from University College Cork, and Kate Kanne (UCD), the original archaeological material from Ferriter’s Cove, which is now stored at UCC, were sent to the CNRS lab in Lille, France, to undergo biomolecular analysis.

Using a technique known as ZooMS that identifies species through proteins preserved in ancient bone collagen, the results found the fragments were not from domesticated cattle as originally thought but instead came from a bear and a wild boar.

As a result, there is currently no archaeological evidence to support the idea that domesticated cattle, and by extension, early farming communities, had reached or influenced Ireland before 4000 BC.

“Ferriter’s Cove is an iconic archaeological site, originally excavated by the Late Professor Peter Woodman, Department of Archaeology, UCC; this new collaboration with colleagues at UCD marks an exciting new phase of research and these remarkable results are set to change our understanding of the earliest evidence for agriculture in Ireland," said Dr Gearey. 

Professor Warren added: “These exciting results show the real value in going back to key sites with new analytical techniques - which can change the stories we tell about our past”

Beyond rewriting one of Ireland's best-known archaeological narratives, the study highlights the value of revisiting important archaeological collections with modern scientific methods, demonstrating how advances can challenge long-held assumptions and reshape the understanding of the past.

Further analyses are now underway to determine whether the bear remains belonged to brown bears or polar bears, with the hope of providing new insights into prehistoric Ireland’s bear populations prior to their extinction during the Bronze Age.

Rethinking how we name and classify our human ancestors following recent evolutionary discoveries

 

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New Monash University research argues our Paranthropus (pictured) and Australopithecus ancestors who lived up to 5 million years ago should be included under the Homo group of species.

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Credit: Ian Towle, Monash University.

Recent advances in our understanding of human evolution challenge the way we currently name and classify our ancestors, according to new research from Monash University.

The research, published in the American Journal of Biological Anthropology, argues that we need a rethink, and proposes reclassifying all species of humans and our closely related fossil relatives that have lived in the past 4-5 million years as part of the Homo genus.

Human evolution is often presented as a straightforward progression through distinct species, from ape-like ancestors, through Australopithecus and earlier members of Homo, culminating in Homo Sapiens that live today.

But the fossil record tells a much more complex story, with new discoveries repeatedly blurring the characteristics once thought to define us and our close relatives.

Lead researcher Dr Ian Towle, a Research Fellow at the Monash Biomedicine Discovery Institute, said recent discoveries are eroding the usefulness and accuracy of current classification, including the current species in our own genus Homo, but also in Australopithecus and Paranthropus, who all lived within the past 5 million years.

“Recent fossil discoveries and advances in evolutionary and genetic analysis make this an ideal time to reconsider whether our traditional taxonomy still accurately reflects human evolution,” Dr Towle said.

“These groups do not necessarily represent distinct evolutionary branches, or ‘clades’, and differences in behaviour and ecology once used to distinguish them have also become increasingly difficult to maintain.

“I propose expanding Homo to include these other groups to provide a more accurate and stable way to represent the complex evolutionary relationships revealed by the growing fossil record.”

In the past 50 years, a growing understanding of evolution has transformed how scientists classify the natural world. 

Modern taxonomy, the science of naming and classifying organisms, increasingly aims to reflect genuine evolutionary relationships, grouping species according to their shared ancestry. 

But when it comes to our own evolutionary history, scientists have been slower to make the transition.

Recent decades have seen a trend to represent a genuine evolutionary group, or clade, of a common ancestor and all of its descendants.

The Homo group have historically been defined by having large brains, sophisticated tool use and particular aspects of anatomy and behaviour. 

But there are now very small-brained members of our genus, and complex behaviours were likely in Paranthropus and Australopithecus.

Dr Towle argues reclassifying Australopithecus and Paranthropus species under the category of Homo will provide a more coherent understanding of our evolutionary history and avoid continual redefinition as we discover new fossils and learn more about our ancestors.

“The more we learn about our ancestors and close fossil relatives, the more we realise how complex and non-linear our family tree is,” Dr Towle said.

“Expanding the Homo genus to also include species of Australopithecus and Paranthropus will allow us to account for differences without regularly reclassifying particular groups.”

Read the research paper: https://doi.org/10.1002/ajpa.70344

A comparison of Neandertal and modern human pelvises

suggests that the male pelvis represents an evolutionary innovation

New study: why do men and women walk differently? A Neandertal pelvis that coexisted with modern humans 35,000 years ago may hold the answer.

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The Neanderthal pelvis

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Credit: Tel Aviv University

A natural mechanism that acts as a shock absorber, stores energy, and releases the energy with every step, potentially facilitating long-distance walking in modern human males.

A new study at the Department of Anatomy and Anthropology of Tel Aviv University, and published in Scientific Reports, offers an explanation for one of the striking differences between men and women: the evolutionary development of the modern human pelvis. By comparing Neandertal pelvises with those of modern humans, the researchers reached a surprising conclusion: the unusual structure of the pelvis may not be that of the Neandertal, as has been assumed for decades, but rather that of the modern human male. According to the researchers, the male pelvis evolved into a unique biomechanical shock absorbing mechanism that stores energy and makes long-distance walking more efficient.

Led by Professor Yoel Rak of the Department of Anatomy and Anthropology at Tel Aviv University, and conducted in collaboration with researchers from Spain, the Technion, Bar-Ilan University, and Ono Academic College, the study is based on a comparison of two nearly complete male Neandertal pelvises, one from Kebara Cave in Israel (Figure 1) and the other from the Sima de los Huesos site in Spain, with dozens of modern human pelvises. Surprisingly, despite their large size and robust construction, the Neandertal pelvises were found to resemble those of modern human females in most measurements and proportions rather than those of modern human males.

For many years, the Neandertal pelvis has been regarded as an anatomically unusual structure requiring a functional explanation of its own. The new findings, however, require a new look at Neandertal pelvises. The ancestral configuration may have been retained in Neandertals and in modern human females, while the modern human male pelvis underwent substantial evolutionary modification, giving rise to a distinctive anatomical configuration.

The central finding of the study is that the hip joints of modern human males are positioned farther forward on the pelvic ring than those of both modern human females and male Neandertals. According to the researchers, this shift created a new mechanical system in which the anterior thigh muscles, attached to the front of the pelvis, function much like a spring, while body weight acts on the posterior part of the pelvis (see Figure 2).

Professor Rak explains that during every step of bipedal walking, the body's center of mass drops downward. This drop traumatizes  the joints and requires energy to raise the body again in preparation for the next step. According to the new model, the distinctive geometry of the male pelvis enables the thigh muscles to cushion the drop of the body's center of mass, store potential energy during the step, and then release that energy immediately afterward-- effectively "springing" the body upward into the next step.

In this way, the pelvis functions as a natural shock-absorber and energy-return system. It may reduce energy expenditure, improve walking efficiency, and thereby provide a significant advantage during long-distance travel on foot. The change in the position of the hip joints also required additional structural adaptations, including the thickening of the pubic bone and deepening of the anterior portion of the pelvis to withstand the new mechanical loads (see Figure 2).

Modern human females, by contrast, could not adopt the full suite of these modifications. According to the researchers, the constraints imposed by childbirth require a relatively shallow pelvis and a sufficiently wide birth canal. As a result, the female pelvis remains closer to the ancestral configuration—the same general configuration found in male Neandertals.

Professor Ella Been of Ono Academic College, a co-author of the study, adds: “This study demonstrates that questions about human evolution are not confined to the distant past. Understanding the evolution of our walking mechanism can contribute to contemporary research in biomechanics, musculoskeletal medicine, rehabilitation, and injury prevention. The perspective provided by the Neandertals helps us better understand the modern human body.”

Professor Rak emphasizes that the findings of the study change the way we understand the evolution of the human pelvis. It is not the Neandertal pelvis that is the anomaly requiring explanation. Rather, it is the pelvis of the modern human male. The mechanism that evolved within the human male represents the evolutionary innovation (Figure 3).

The researchers note that the study presents a new biomechanical model that may explain a substantial part of the human pelvis’s sexual dimorphism—the anatomical differences between females and males. The research also demonstrates that even in human macroscopic anatomy, a field that might appear to have been thoroughly explored, there is still potential to uncover previously unrecognized structures, geometries, and mechanisms of biological significance.

Link to the article:

https://www.nature.com/articles/s41598-026-59915-8

Ancient maritime voyagers carried symbolic art 4,000 years ago

A 4,000-year-old painted stone plaque discovered on a remote Indonesian island is the first known example of portable art belonging to the Austronesian Painting Tradition (APT), providing a rare glimpse into the symbolic world of some of history’s greatest maritime voyagers. 

 

Caption

A 4,000-year-old painted stone plaque discovered on Wetar Island, Indonesia.

Credit

Shimona Kealy/Australian Nattional University.

The discovery was made by an international team led by archaeologists from The Australian National University (ANU) and Indonesia’s National Research and Innovation Agency (BRIN) during excavations at Huknaur rockshelter on Wetar Island, eastern Indonesia. 

The plaque bears a distinctive red concentric-circle and radiating “sun-ray” design characteristic of the APT – a style of rock art found across eastern Indonesia and the Western Pacific in regions where Austronesian languages are spoken. 

Although APT paintings are widespread, most occur on cave and rockshelter walls and are difficult to date, leaving their chronology poorly understood. The Wetar plaque provides the first evidence that these designs were also painted on portable objects, while its securely dated archaeological context provides a rare age for this characteristic motif. 

Lead author Professor Sue O’Connor, from The Australian National University (ANU), said the discovery changes our understanding of how these symbols may have been used. 

"This is the first portable example of Austronesian painted art ever found archaeologically,” Professor O’Connor said. 

“Portable symbols could travel with people and may have helped communicate shared identities, affiliations and beliefs between island communities. Similar sun-like designs were historically painted on boats and other objects, where they could function as symbols of protection and group identity.” 

Co-author Dr Simona Kealy, of the ANU, said radiocarbon dating of the archaeological deposits placed the plaque between approximately 4,090 - 3,900 years ago, when Austronesian-speaking peoples were rapidly dispersing into Island Southeast Asia. 

“This discovery shows that the characteristic sun-ray motif was already part of the APT during the earliest Austronesian expansion into southern Wallacea,” Dr Kealy said. 

 “These people were extraordinary seafarers, rapidly dispersing across thousands of kilometres of ocean. The Wetar plaque shows that art and shared symbolic traditions were part of this great maritime dispersal from its earliest phases.” 

The plaque was found in a preceramic layer, indicating that the APT reached Wetar before pottery – one of the principal material traits traditionally used by archaeologists to trace Austronesian expansion. 

ANU co-author Dr Ceri Shipton said this provides a new perspective on what the earliest Austronesian pioneers brought with them. 

“This discovery shows that Austronesian pioneers arrived with a compelling ideology represented by the APT paintings, prior to more extended contacts bringing pottery,” Dr Shipton said. 

“People didn’t just carry technologies and possessions when they voyaged to new islands. They carried ideas, identities, and new ways of understanding the world.” 

The study, 4,000-year-old painted plaque from Southeast Indonesia reveals Austronesian Painting Tradition preceded Neolithic pottery, will be published in the Proceedings of the National Academy of Sciences (PNAS). 

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Journal

Proceedings of the National Academy of Sciences

DOI

10.1073/pnas.2611580123 

Last common ancestor, no matter its feet, could have been a vertical climber

 New research suggests that no matter what we eventually determine the last common ancestor of humans and chimpanzees to be, we’ll learn it was a primate that climbed trees.

Humans and chimpanzees began their separate evolutionary paths between 6 and 7 million years ago when they split from the last common ancestor (LCA) they shared. Debate about the LCA hinges in part on the tree-dwelling environment from which humans emerged – which involved living among the high-up horizontal branches or being able to get there from the ground, or, more likely, both.

Chimpanzees have ankle flexion that makes them skilled tree trunk climbers, but monkeys have been thought to navigate trees with their arms – which would influence what kind of ancestor we’re looking for, one that climbed up trunks or lived in treetops full time.

Video evidence from West Africa suggests there may be no such distinction, at least based on foot structure: Researchers from The Ohio State University observed and confirmed with measurements that wild sooty mangabey monkeys, known to have feet that lack chimps’ versatile ankles, display foot bone flexibility that facilitates vertical climbing up skinny tree trunks to hide, forage or sleep.

“People are making behavioral inferences from fossils, and some say a monkey can’t vertically climb as well as an ape can,” said first study author Luke Fannin, assistant professor of anthropology at Ohio State. “We’re saying there’s a functional equivalence here. So you can’t rule out vertical climbing just because something doesn’t have a chimpanzee-like foot.”

The research appears this week in Proceedings of the National Academy of Sciences.

Identifying the last common ancestor is considered key to helping us understand what led to bipedalism, which is done habitually only by humans. We know we’re apes, but this study makes the point that even if the ancestor had a more monkey-like foot morphology, it could still climb like an ape.

“Part of paleoanthropology is understanding how our evolution happened, and it’s often through the hallmark of how we move because modern humans move quite differently than our cousins, the chimpanzees, do, and they’re the living primate we’re most closely related to,” Fannin said. “And we’re trying to understand why that is.”

Fannin recorded the videos of mangabeys in the wild at the Taï Forest Monkey Project field station in Ivory Coast that is co-directed by W. Scott McGraw, professor and chair of anthropology at Ohio State and senior author of the paper.

“The great thing about having the video is that it allows us to capture exactly what the monkey is doing in a high-resolution manner. So we can actually say how the joint is loaded. Before, we had hunches, but in this way, it’s far more precise,” McGraw said.

The chimpanzee ankle can flex upward at a 45-degree angle during a tree climb, compared to most human ankles’ capacity to flex about 20 degrees. Fannin found that the mangabey foot achieves a 46-degree flex in its midfoot during a vertical climb.

This poses a challenge to differing schools of thought about how the LCA moved and the kind of foot it needed to get around a forest environment – theories differ on whether the foot structure was required to be more like a chimp’s or a monkey’s.

“What’s neat about this paper is it adds clarity, but it also makes the broader picture more fuzzy,” McGraw said. “Because this notion that you have to have a foot like an advanced ape to vertically climb, which is a difficult task, is not true. You’ve got a bunch of monkeys that aren’t extinct – and which can be filmed – that are very competent at performing a biomechanically challenging behavior right now in a forest in West Africa.

“The videos that Luke made in Taï are particularly important because they provide some of the first kinematic documentation of a locomotor behavior in a monkey that has largely been unrecognized or underappreciated.”

There are modern hunter-gatherers and human foragers who are competent vertical climbers as well, a skill believed to be associated with flexibility in their ligaments, tendons and muscles rather than their foot bones.

But Fannin and McGraw note that though modern humans may be defined by walking on two feet, we are focused on ascent, on reaching new heights in a literal sense – a sign that our arboreality, that ancestral connection to trees, is not just anatomical but also a behavioral hallmark.

“Arboreality is fundamental to understanding primates – including ourselves – because it has shaped our body to a large degree: hands and feet, wrists and ankles, nails instead of claws, etc.,” McGraw said.

Added Fannin, “Regardless of where you’re starting from, which we don’t know yet, vertical climbing is universal and the anatomy is going to perform that behavior. So I think that to get at the question of a monkey-like or ape-like last common ancestor, we need more fossils.”

Ancient Egyptian tomb shows how burial trends changed over hundreds of years

 

Placement of mummies in a Theban tomb – from individual placement to stacking of bodies – shows how burial practices and their symbolic implications changed over time

Peer-Reviewed Publication

Frontiers

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Figure 3 — Mummified individuals from Side Chamber 3 of Theban Tomb 209, showing variation in body orientation and arm position.

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Credit: Proyecto dos cero nueve, Universidad de La Laguna / Jared Carballo-Pérez.

The Theban Necropolis, opposite Luxor, is comprised of more than 400 tombs. In a new Frontiers in Environmental Archaeology study, researchers in Spain examined a part of one of these tombs – chamber three in tomb TT 209 – more closely to reconstruct how this burial space was used and reused between its construction during the Twenty-fifth Dynasty (754-656 BCE) and the Ptolemaic period (305–30 BCE), when it was abandoned.

“We found a total of 16 mummified human individuals, a mummified dog, and a disturbed deposit containing the remains of at least four individuals,” said first author Dr Jared Carballo-Pérez, a researcher at the University of La Laguna. “The detailed study of the bodies indicates neither chaotic accumulation nor a loss of the original ritual over time. Rather, there was a spatial logic in which each new deposition was adapted to the presence of previous bodies – a kind of funerary memory in the processes of reuse.”

Senior author Dr Miguel Ángel Molinero Polo, a professor of Egyptology at the University of La Laguna, added: “We have few details regarding how the people who entered tombs behaved, what their motivations were in each historical period, and how they conceptually reconfigured the pre-existing space.”

Tomb through time

To deepen the understanding of the deposition of bodies and the transformation of funerary space, the team excavated the chamber, photographed the mummies, and produced sketches and descriptions of their position, orientation, and relationship with the tomb’s structures. The chamber contains nine funerary deposits, comprising individual and multiple burials, as well as associated funerary objects.

For the earliest deposits, the team observed relatively separated burials where bodies were placed in coffins.

“The earliest individuals buried here appear to have been of high social standing, as they were interred in coffins, with funerary nets and amulets, and with an assemblage containing costly items, such as the contents held in Phoenician amphorae, a large number of which were found alongside them,” said Molinero Polo.

Later, towards the end of the 25th dynasty and the Persian period (around 680-404 BCE), bodies started being inserted into any space still available. This resulted in denser use of space. In some cases, a change could be seen in the positioning of limbs, for example a folded-in arm whereas in earlier burials arms were typically stretched out. Also in the Persian period, the team observed a shift from individual deposits to a vertical way of arranging bodies. Superposition of bodies was found in two thirds of the burials in the chamber.

Reconstructing funerary practices

In the southeastern section of the chamber, four mummies and one mummified dog are buried on top of one another in the Ptolemaic Period.

“The bodies buried in vertical superposition did not have coffins but were carefully mummified. They also can be associated with upright jars that point to a specific ritual not found in the earlier phases of the tomb’s use,” said Molinero Polo.

“One detail I find quite beautiful is the presence of a mummified dog placed directly on top of the mummies of a man and a woman,” said Carballo-Pérez. “This could indicate a close relationship between these human individuals and the animal, an idea that I think is quite easy to empathize with.”

“It could also reflect a further change in ritual practice, with an animal taking on the role of a psychopomp, a symbolic helper in the journey to the afterlife,” added Molinero Polo.

This, alongside certain changes in the arrangement of bodies – for example, in later deposits individuals were buried with both arms folded over their chests in what Egyptologists call the Osirian position – suggests that the tomb did not become disordered or without structure, or that cultural rites were lost. Instead, the chamber should be considered a repeatedly reactivated space, reconfigured by new burials that transformed the organization and meaning of space itself without erasing the past.

In some funerary deposits, it is difficult to identify the exact sequence of depositions and reconstruct the precise intentionality behind them, the team noted. This is due to century-long use during which the chamber flooded multiple times as well as fires and human re-entry that transported debris within the tomb.

“Nevertheless, what we present means that deposits that were previously considered ‘disordered’ can be reinterpreted,” concluded Carballo-Pérez. “This helps us develop a better understanding of the social behaviors behind funerary practices.”

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Journal

Frontiers in Environmental Archaeology

Pre-Hispanic farmers built giant water system bottom-up, archaeologists reveal

 Communities living in Colombia thousands of years ago achieved an engineering wonder of the world based on cooperation among family groups without top-down government, a new study shows. Archaeologists argue that policymakers in Colombia should now adopt a similar strategy to solve the country’s current water management crisis.

The pre-Hispanic field systems of La Mojana in the Colombian Caribbean are so vast you can see them from a plane at high altitude. Their canals and raised fields – in use from the first centuries BC until the 11th century AD – cover an astonishing 500,000 hectares, roughly the same size as the Grand Canyon National Park, or three times the size of London.

It has traditionally been assumed that powerful rulers must have ordered and managed such an ambitious infrastructure project because of its complexity and the amount of work thought to be involved. In a study published today in Communications Sustainability, however, a University of Cambridge-led archaeological team argues that the work was most likely locally-led, cooperative, and much faster than previously assumed.  

The findings are important historically but also offer hope to Colombians today who are suffering from a water management crisis linked to climate change, intensive farming and policy failure.

“These field systems are so impressive that people have assumed they were achieved by hierarchical chiefdoms. Our data tells a very different story,” said the study’s lead author, Dr Jasmine Vieri, from the University of Cambridge’s McDonald Institute for Archaeological Research.

“Our findings indicate that local communities were capable of building these systems in very short periods of time, and organising themselves rather than relying on a powerful external force.”

The societies responsible for these hydraulic systems in La Mojana were contemporary with the Maya, and with the broader Mesoamerican and Andean state-level societies, which culminated in the huge Aztec and Inca empires a few centuries later. The pre-Hispanic populations occupied an area where, the researchers point out, there is no evidence of state-level societies. It has been assumed – encouraged by evidence of elaborate gold work and ceramics – that they were hierarchical chiefdoms on their way to state formation. By contrast, the new findings support the idea that these people chose to organize themselves far more horizontally and were able to achieve great things.

Their raised field system managed huge quantities of water during heavy rains, gradually redirected it in drier months, buffering against both drought and floods. The network of canals redistributed water from permanent bodies of water around raised areas of housing. The system provided more fertile soils for cultivation in dry seasons and may have helped locals to trap fish.

Using satellite imagery, the researchers mapped a 500-hectare portion (roughly 700 football pitches) of Pre-Hispanic field systems in the municipality of San Macros, Sucre. They studied the infrastructure at an unprecedented level of detail, recording the dimensions and volume of 1,600 ridges and 63 housing platforms. They worked out that when first constructed the formations were around 1.4 metres high from the top of the ridge to the lowest point of the canal.

The international team – including researchers from the Colombian Institute of Anthropology and History (ICANH), and University of Santiago de Compostela in Spain –   then developed a new method to quantify the labour needed to build this system and considered the social and spatial organization most likely to have underpinned this work.

Dr Jasmine Vieri said: “We are confident that one of these canal-ridge systems could have been built in less than two months, around half of a dry season. That’s a far lower labour investment than has been previously assumed, and manageable through cooperation.”

The researchers factored in volumes of moved earth, as well as information about local geology, indigenous working practices, population density and available technology. Starting from an estimated population of 1,600 people in the study area, they based their calculations on a workforce of 800 people which, the researchers emphasise, represents a conservative estimate, given ethnographic evidence that men, women and probably children traditionally engage in subsistence farming.

Soils in the Colombian Caribbean are heavy clay which would have made the work harder and there were no metal shovels in the region in this period. The workers may have used wood tools but this remains unproven.

The study springs from Cambridge’s ERC-funded REVERSEACTION project, which investigates how technologies are sustained in stateless societies, and how collective action can achieve great things without coercion.

Professor Marcos Martinon-Torres, REVERSEACTION’s lead and senior author, said: “Arguments for centralised, top-down planning, unsupported by data, risk obscuring the agency of indigenous pre-Hispanic populations. Pre-Hispanic societies were inventive and cooperative, they worked with nature rather than trying to obstruct it. And we already know that recovering ancestral practices has positive societal impact today through local populations connecting with their heritage through technology.”

Evidence for the use of raised field systems in this region ends before the Spanish arrived in the sixteenth century. It isn’t clear why they stopped being used but it has been suggested there was population movement from the lowlands towards mountainous areas.

The researchers argue that the pre-Hispanic sustainable solution to water management can be adopted by local populations without the need for state intervention. Instead of redistributing water flow, the Colombian government has often adopted the opposite strategy of attempting to block water flow to prevent flooding and adapt the land for agricultural and livestock activities based on models designed for non-flooding environments. But dykes have proven incapable of holding water back. Since 2021, the Caregato dyke has suffered multiple breaches, causing losses for local communities and ecosystem damage. At other times, the region suffers from severe droughts.

Study author Dr Fernando Montejo Gaitán, from the Colombian Institute of Anthropology and History (ICANH), said: “Policymakers have shown interest in these ancient systems, but lacked data. Our study is the first to show that these sustainable solutions can be organised locally and collectively. Local people may need resources from the state but not necessarily state intervention.”

The researchers have made their code open source to enable researchers to apply the same methods to data sets relating to other regions.

Reference

J. Vieri, F. Montejo Gaitán, M. Carrero-Pazos, M. Martinón-Torres, ‘Collective labour and sustainability of pre-Hispanic field systems in La Mojana’, Communications Sustainability (2026). DOI: 10.1038/s44458-026-00128-5