Evolutionary Insights by Anthropology.net

The Deep Past of Mummification

Long before pharaohs wrapped their dead in linen or the Chinchorro people of coastal Chile painted their desiccated ancestors, small bands of hunter-gatherers in tropical Asia were carefully tending to their dead. They lived in humid monsoon climates where natural desiccation was impossible. Yet between 12,000 and 4,000 years ago they developed a method of preservation that was as much ritual as practical: smoke-drying their dead.

The findings, published in Proceedings of the National Academy of Sciences show that the oldest known deliberate mummification in the world occurred in southern China and Southeast Asia, millennia before the celebrated cases of the Nile Valley or the Atacama coast.

“These burials show that the preservation of the dead was not only a technical feat but part of a shared set of beliefs spanning thousands of years and thousands of kilometers.”

The Evidence: From Caves and Shell Middens

Archaeologists examined more than 50 pre-Neolithic burials from 11 sites across southern China, Vietnam, and Indonesia, including Zengpiyan Cave and Huiyaotian in Guangxi, and Con Co Ngua in northern Vietnam. The dead were buried in strikingly crouched or squatting positions. Some were tightly bound, with limbs pressed against the torso. Many showed traces of blackened bone or cut marks around major joints.

Radiocarbon dates push some of these burials back to 12,000 years ago. Laboratory tests—including X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR)—revealed subtle changes in bone chemistry consistent with exposure to low-temperature fires and long periods of smoking rather than high-heat cremation.

What Smoke-Drying Looked Like

The burn patterns suggest bodies were not burned directly but placed over or near smoldering fires. Lower limbs, elbows, and frontal areas of the skull showed the most thermal alteration, implying careful positioning.

“Rather than reducing the body to ash, smoke-drying preserved the skin and joints long enough for burial, producing skeletons so tightly flexed that no empty space remained between the limbs and torso.”

Ethnographic parallels help make sense of the archaeological record. The Dani and Anga peoples of Papua New Guinea still practiced smoke-drying of ancestors well into the 20th century, seating them above smoldering fires for months at a time. These practices produced bodies in the same tightly bound postures documented in the ancient burials.

Rethinking “Dismemberment”

Cut marks and dislocated bones once interpreted as mutilation may instead represent steps in the mummification process. In several Guangxi burials, for instance, skulls were placed in unusual positions or limbs bundled like firewood. These arrangements are consistent with post-mummification movement, delayed burial, or ritual rearrangement rather than violence.

A First Layer of Humanity

The study also reinforces the idea of an early population layer across Southeast Asia closely related to the ancestors of Indigenous Australians and Papuans. Craniofacial and genetic evidence ties the smoke-mummified individuals to this “first layer,” which arrived in the region long before Neolithic farmers swept in from the north.

“This deep biological and cultural continuity suggests smoke-drying was not an isolated custom but part of a much older tradition linking ancient Southeast Asia, New Guinea, and Australia.”

A Cultural Technology for the Tropics

Why go to such lengths? In tropical settings, bodies decompose rapidly. Smoking offered a technological solution, but the consistency of the practice across space and time implies it also carried symbolic meaning. Among the Anga, the mummified body still houses the spirit of the deceased; among Aboriginal groups in South Australia, preservation connects the dead to immortality. Such beliefs provide a glimpse of the spiritual landscape of early Homo sapiens in Southeast Asia.

Beyond Southeast Asia

Flexed burials with possible signs of smoke-drying appear in Jomon Japan, Gadokto Island off Korea, and even in parts of Australia, hinting at a broader tradition of mortuary practice that may extend back to the first dispersals of modern humans through southern Asia.

Why It Matters

This discovery reframes the timeline of one of humanity’s oldest rituals. It shows that complex mortuary behavior did not arise solely with farming societies but was deeply rooted in the hunter-gatherer past. It also underscores how ancient technologies—fire, binding, smoke—were enlisted not just for food or shelter but for shaping memory, identity, and relationships with the dead.

Related Research

* Arriaza, B. T. (1995). Beyond Death: The Chinchorro Mummies of Ancient Chile. Smithsonian Institution Press.

* Aufderheide, A. C., et al. (1993). The Chinchorro mummies of northern Chile. American Journal of Physical Anthropology, 91(2), 189–201. https://doi.org/10.1002/ajpa.1330910206

* Reid, J., et al. (2021). Mortuary variability and body treatment in the Jomon Period. Quaternary International, 574, 19–31. https://doi.org/10.1016/j.quaint.2020.07.006

* Lloyd-Smith, L., et al. (2013). New insights from the Niah Cave burials, Sarawak. Antiquity, 87(337), 1–17. https://doi.org/10.1017/S0003598X0004999X

* Matsumura, H., & Oxenham, M. (2014). Demographic transitions and migration in prehistoric Southeast Asia. Proceedings of the Japan Academy Series B, 90(6), 239–249. https://doi.org/10.2183/pjab.90.239

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High in the mountains and across the scattered islands of Papua New Guinea lives a population whose DNA tells a story about the earliest dispersals of Homo sapiens. For decades, scientists debated whether these communities were descendants of a separate migration out of Africa or part of the same wave that gave rise to other non-African peoples. A new study in Nature Communications points toward an answer, and it is as intricate as the landscape itself.

“Perhaps adaptations to tropical climates make Papuans look more like Sub-Saharan African groups, even though their genetics clearly link them to other Asian populations,” said Mayukh Mondal, who led the research. “More studies are needed to uncover how evolution shaped this remarkable population.”

A puzzle stretching back 60,000 years

Modern humans left Africa between 50,000 and 70,000 years ago. Archaeological finds in Sahul (the ancient landmass joining Papua New Guinea and Australia) show human presence by at least 50,000 years ago, older than many sites in Europe. For decades, this led to the idea of a “first out of Africa” migration — a separate coastal trek that seeded Oceania before the later expansion into Eurasia.

But mitochondrial and Y-chromosome studies failed to confirm a distinct ancestry. While traces of earlier dispersals cannot be ruled out entirely, genomic studies increasingly point to a single main migration for all non-African populations.

Papua New Guineans complicate this picture. They carry the highest levels of Denisovan DNA in the world — remnants of encounters with a now-extinct hominin whose remains are known mainly from a Siberian cave. This inheritance hints at stopovers in Southeast Asia where Homo sapiens and Denisovans may have met.

Using AI to model ancient population history

The new study combined high-quality genome data with neural-network models to test demographic scenarios explaining the origins of Papua New Guineans. The results point to a sister relationship with other Asian populations rather than a separate, older migration.

The authors also identified a severe population bottleneck in the ancestors of Papua New Guineans. Numbers may have plunged soon after arrival and remained low for millennia. Unlike other non-African populations, they never experienced the farming-driven demographic booms that transformed Eurasia.

“This unique demographic history left genetic signatures that, if misunderstood, could look like evidence of a contribution from an unknown population,” Mondal explained.

Why it matters for anthropology and human evolution

These findings deepen the story of how Homo sapiens expanded and adapted. Papua New Guinea represents a living repository of the earliest human movement into Oceania and the persistence of small-scale societies over tens of millennia. Isolation and survival bottlenecks have preserved signatures of one of humanity’s oldest population histories.

This work also underscores how demographic change — not just gene flow or selection — can shape the patterns we see in human DNA. It challenges scientists to disentangle the effects of ancient migrations from the echoes of small, isolated populations.

Related research

* Malaspinas, A.-S., et al. (2016). “A genomic history of Aboriginal Australia.” Nature, 538(7624), 207–214. https://doi.org/10.1038/nature18299

* Bergström, A., et al. (2021). “Origins of modern human ancestry.” Nature, 590(7845), 229–237. https://doi.org/10.1038/s41586-021-03244-5

* Jacobs, G. S., et al. (2019). “Multiple deeply divergent Denisovan ancestries in Papuans.” Cell, 177(4), 1010–1021.e32. https://doi.org/10.1016/j.cell.2019.02.035

These studies show Papuan and Aboriginal Australian genomes as key evidence for the earliest dispersals of modern humans and the mosaic of archaic admixture events that followed.

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A century ago, British doctors in colonial Africa were puzzled by goiter, a swelling of the neck linked to iodine deficiency, appearing in people living far from the sea. Yet this phenomenon had much deeper roots. Across thousands of years, shortages and surpluses of essential minerals such as iodine, iron, zinc, and calcium quietly sculpted the human genome. A new study in The American Journal of Human Genetics argues that the genetic fingerprints of these pressures are still visible today.

“Different human populations lived in different environments, so they had to adapt to different kinds of environmental pressures, such as disease and diet, that over time can drive trait differences,” said Jasmin Rees, first author of the study.

The Evolutionary Weight of Trace Elements

Micronutrients are the molecular background of life. Iron builds blood; zinc shapes immunity; calcium hardens bones; iodine fuels the thyroid. Yet their availability depends on geography. Soils vary, rivers leach or concentrate minerals, and whole ecosystems express these differences in the food they produce. Before vitamins and fortification, human populations had no buffer.

The new study took a broad look at this hidden map, asking whether the evolutionary signatures of micronutrient availability were still encoded in our DNA. Researchers examined 276 genes linked to how humans absorb, transport, or use 13 essential minerals, scanning the genomes of more than 900 people from 40 populations worldwide.

“Different human populations lived in different environments, so they had to adapt to different kinds of environmental pressures… This paper is a first step in understanding which populations might be most at risk.” — Jasmin Rees

Genes as Geological Records

For every mineral studied, at least one population carried signs of adaptation in the genes regulating its use. This was not a localized effect—it was global. Each essential mineral left its mark on at least one group of humans at some point in history.

In the Maya, whose ancestors lived in iodine-poor soils, the researchers found strong evidence of genetic changes in iodine metabolism. In parts of South Asia with unusually high magnesium levels, they identified two genes suggesting adaptation to prevent magnesium toxicity. The findings suggest that across continents and millennia, genes responded to the quiet but persistent tug of local geology.

A Mosaic of Human Diets

Before agriculture, people already depended on their environment for trace elements. But farming and settlement likely intensified the problem. Soil depletion, monoculture, and new diets amplified shortages and sometimes created surpluses. Over thousands of years, these pressures influenced which gene variants thrived.

“This paper is a first step in understanding which populations might be most at risk,” Rees said. “We hope with more studies, the findings can eventually help inform public health going forward.”

Why It Matters for the Present

Modern human populations are not starting from scratch. Each carries a legacy of past adaptations. As climate change and industrial farming continue to strip soils of nutrients, understanding these inherited vulnerabilities could help predict who is most at risk for deficiency-related disease.

Anthropologists and geneticists are now asking how deep this pattern runs. Did micronutrient pressure shape not just physical health but also cognition or reproductive patterns? Could mineral deficiencies explain aspects of migration, settlement, or even myths about sacred springs and salt? These are open questions, but the Rees team’s data lay a foundation.

Related Research

Other studies echo this focus on diet and evolution, each shows how diet-related pressures have repeatedly shaped the human genome.:

* Andrés, A. M. et al. (2020). Balancing selection maintains a form of the APOL1 gene that protects against sleeping sickness but increases kidney disease risk. Nature Genetics, 52, 835–845. https://doi.org/10.1038/s41588-020-0633-8

* Mathieson, I., & Mathieson, S. (2018). FADS gene adaptation to plant-based diets in Europe. Nature Ecology & Evolution, 2, 1887–1892. https://doi.org/10.1038/s41559-018-0697-8

* Tishkoff, S. A., et al. (2007). Convergent adaptation of lactase persistence in Africa and Europe. Nature Genetics, 39, 31–40. https://doi.org/10.1038/ng1946

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Beneath the soil of northern Latvia lies one of Europe’s largest Stone Age cemeteries. For decades, Zvejnieki has fascinated archaeologists for its hundreds of burials, red ochre stains, and pendants made from animal teeth. But the flaked stone tools—often seen as ordinary or utilitarian—sat largely ignored in museum drawers. A new multiproxy study published in PLOS ONE changes that, revealing a surprising portrait of gender, age, and ritual in prehistoric Europe (Petrović et al. 2025).

“Our findings overturn the old stereotype of ‘Man the Hunter,’” said Aimée Little of the University of York. “Lithic grave goods were not just for men. Women and children were equally likely to be buried with them.”

A Cemetery with Deep Time

Zvejnieki sits on a former island in Lake Burtnieks, its cemetery active from roughly 7500 to 2500 BC. Over 330 graves have been excavated, spanning Mesolithic and Neolithic lifeways. Many burials are lined with red ochre; some children were interred with amber discs over their eyes or small figurines tucked near their heads. The new study zeroed in on 158 stone tools from 33 graves, analyzing their raw materials, manufacture, and microscopic wear traces.

“A missing part of the story was understanding why seemingly utilitarian items were given to the dead,” noted Anđa Petrović of the University of Belgrade.

Stone Tools Beyond Utility

The team found that flakes, scrapers, bifacial points, and blades were buried with adults, children, and especially older adults—without strong ties to biological sex. Children were in fact the most common recipients of lithic grave goods. About half of the artifacts showed no signs of use, suggesting they may have been made specifically for burial.

This deliberate inclusion echoes patterns seen across the eastern Baltic. Some tools appear to have been intentionally broken before deposition, hinting at a shared ritual tradition. Others bear microscopic traces of hide-working, meat-cutting, or mineral processing, suggesting these tools once played a role in daily life before being offered to the dead.

Why This Matters for Archaeology

For decades, archaeologists often assumed that stone tools signified male hunters, while ornaments and pendants marked female or child burials. The Zvejnieki data undermine that binary. Instead, stone tools in death seem to reflect community-wide practices of mourning, memory, and identity.

“We cannot make gendered assumptions about Stone Age grave goods,” Petrović emphasized. “Lithics played an important role in the mourning rituals of children and women as well as men.”

Ritual as a Community Act

One of the richest burials belonged to a genetically female older child (Burial 207) interred with seven bifacial points, six scrapers, and sixteen flakes. Another, a young adult female (Burial 211), was accompanied by an ochre-rich deposit containing dozens of flakes and blades. These assemblages dwarf those of many adult male graves.

Lithic grave goods were not just for men. Women and children were equally likely to be buried with them.” — Aimée Little

“We cannot make gendered assumptions about Stone Age grave goods.” — Anđa Petrović

These findings point to a complex ritual life where children and women could be at the center of symbolic acts, not on the margins. Even simple flakes—usually the most humble of stone artifacts—were sometimes singled out as meaningful offerings.

A Wider Baltic Tradition

Comparable funerary practices have been documented at other sites in Finland and Russia, suggesting a broader cultural sphere. The Stone Dead Project database now provides open access to Zvejnieki’s lithic inventory, allowing researchers worldwide to compare burial customs across northern Europe.

Related Research

Other studies support a rethinking of gender and burial practices in prehistoric Europe:

* Nilsson Stutz, L. (2003). Embodied Rituals and Ritualized Bodies: Tracing Ritual Practices in Late Mesolithic Burials (Lund University).

* Jordan, P. (2003). Material Culture and Sacred Landscape: The Anthropology of the Siberian Khanty (AltaMira).

* Schulting, R. J., & Richards, M. P. (2002). “The wet, the wild and the domesticated: The Mesolithic–Neolithic transition in the western British Isles.” Proceedings of the Prehistoric Society, 68, 101–123. https://doi.org/10.1017/S0079497X00001487

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On a windswept plateau in Sardinia, the remains of nuraghi rise like weathered chess pieces. These stone towers belong to the island’s Nuragic culture, which flourished in the late Bronze and early Iron Age. Scattered across the island are hundreds of miniature bronze figures—bronzetti—depicting warriors with horned helmets, archers, ships, animals, and deities. For more than a century, scholars debated where the metal for these figurines came from. A new study in PLOS One offers the clearest answer yet.

“The bronzetti were primarily made from copper sourced in Sardinia itself, sometimes blended with copper from the Iberian Peninsula,” explains Daniel Berger of the Curt-Engelhorn Center for Archaeometry, who led the geochemical analysis. “We found no evidence of copper from the Levant, which only became clear once we examined osmium isotopes.”

A Multi-Proxy Look at Metal

The team combined multiple isotope signatures—copper, tin, lead, and osmium—to build a geochemical fingerprint of each figurine. This “multi-proxy” approach revealed a kind of ancient recipe book: local copper mixed strategically with imported Iberian copper and imported tin. Although Sardinia had its own tin and lead deposits, these were not used for the bronzetti, suggesting deliberate sourcing choices.

“Archaeological methods give us the context,” says Helle Vandkilde of Aarhus University. “But it is the isotope data that allow us to pinpoint the origin of the metals and even detect strategic mixing, perhaps to influence the color or hardness of the final objects.”

The study covered bronzetti from three of the island’s largest Nuragic shrines, showing remarkably similar chemical signatures across sites. This consistency implies shared production standards and widespread coordination, not isolated local workshops.

Horned Helmets and Northern Echoes

The bronzetti also reframe a bigger question: how far did these Mediterranean networks reach? For Vandkilde’s team, the answer extends all the way to northern Europe.

“We only have to think of the Viksø helmets or the warriors on Scandinavian petroglyphs wearing horned helmets,” says Heide Wrobel Nørgaard of Moesgaard Museum. “With new knowledge about where the metal for these figures came from, we are one step closer to mapping the connections between Sardinia and Scandinavia.”

Iconography links Sardinia and the Nordic Bronze Age between 1000 and 800 BCE. Horned helmets appear in both regions, from Sardinia’s bronze miniatures to giant stone carvings in Sweden. The new isotopic data make it harder to dismiss these similarities as coincidence. Instead, they hint at overlapping ritual spheres or exchange networks stretching from the central Mediterranean to the Baltic.

Bronze Age Connectivity Reconsidered

This research adds to a growing body of evidence suggesting that the late Bronze Age was a time of unprecedented connectivity. The Sardinian data echo findings from British middens, where isotopes show animals transported hundreds of kilometers for communal feasting, and from tin-trade studies tracing Cornish metal to the eastern Mediterranean.

By pulling chemical signatures from artifacts as small as a figurine, archaeologists can reconstruct the movements of goods, ideas, and people. These patterns challenge the idea of insular cultures and instead reveal webs of interaction spanning seas and millennia.

“Having the opportunity to analyze the famous bronze figures from Sardinia is an important step toward understanding how the island was a central piece of the metal trade during the Bronze Age,” says Berger.

Related Research

* Ling, J., Hjärthner-Holdar, E., Grandin, L., Stos-Gale, Z., Kristiansen, K., Melheim, L., … & Mårtensson, A. (2014). Moving metals or indigenous mining? Provenancing Scandinavian Bronze Age artefacts by lead isotopes and trace elements. Journal of Archaeological Science, 41, 106–132. https://doi.org/10.1016/j.jas.2013.07.018

* Sabatini, S., & Bergerbrant, S. (Eds.). (2020). The World of the Nordic Bronze Age. Oxbow Books.

* Wood, B. J., & Williams, J. (2022). Tin isotopes and the Bronze Age trade networks. Antiquity, 96(389), 1023–1040. https://doi.org/10.15184/aqy.2022.73

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In the late second millennium BCE, the landscape of what is now northern Germany was dotted with monumental burial mounds. Among the largest and most elaborate are those at Seddin, in the Prignitz region of Brandenburg. Archaeologists have long noted that the artifacts buried here—razor-thin gold ornaments, fine bronze vessels, and exotic glass beads—hint at a community plugged into far-reaching networks of exchange. New isotope analysis of cremated human remains adds an even more striking layer: many of the dead themselves were born far from the sandy soils in which they were buried.

“Most buried individuals show a non-local, foreign strontium signature,” said Professor Kristian Kristiansen of the University of Gothenburg. “This aligns with archaeological evidence of intensified trade between these regions.”

An Elite Hub of the Late Bronze Age

Between 900 and 700 BCE, Seddin’s monumental mounds marked more than just local power. They were nodes in an interconnected world stretching from southern Scandinavia to northern Italy. The recent study, led by Dr. Anja Frank, is the first bioarchaeological investigation of Seddin’s elite burials. It shows that mobility was not limited to goods; it included people of high status.

“We were able to identify that their chemical composition was foreign to the region,” Dr. Frank explained. “However, the investigated individuals generally came from outstanding burial mounds, meaning our results represent only the elites.”

The findings emerge from the analysis of cremated remains—bones reduced to fragments but still chemically resilient. In particular, the researchers targeted the petrous portion of the temporal bone, or inner ear, which forms in early childhood and resists alteration even during cremation.

Reading Mobility in Bone Chemistry

Strontium isotopes, derived from the local geology, enter the food chain through plants, animals, and drinking water. When children grow, their bones and teeth lock in a regional chemical “signature.” Comparing this signature in human remains to the local baseline allows archaeologists to tell whether an individual grew up in the same area where they were buried.

The Seddin study compared the isotope ratios of 30 cremated individuals to a reference baseline built from local soils and waters. The results show that most of the sampled individuals had isotope values incompatible with the Seddin region but consistent with regions such as southern Scandinavia, central Europe, and possibly northern Italy.

“Identifying the area of origin is less straightforward, as multiple areas can have the same strontium composition,” Dr. Frank noted. “We narrowed it down further using the archaeological record.”

Elite Networks and the Movement of Ideas

The isotope results dovetail with decades of artifact studies. For example, horned helmets appear in both Sardinia and Scandinavia at the same time, while Scandinavian-style razors and Italian bronze vessels occur in northern Europe. The new data suggest that such items were not only traded but also accompanied by people who may have brokered or controlled exchange networks.

Dr. Serena Sabatini, co-author of the study, highlights that Seddin’s elite dead fit within a broader European pattern of mobility during the Late Bronze Age. “This was a time when the value of bronze shifted, trade routes realigned, and elite groups across Europe began forging new identities,” she said.

Reconsidering “Local” Bronze Age Communities

The Seddin study prompts a reassessment of what archaeologists call “local culture.” Monumental mounds, elite goods, and isotope data together suggest that the elites of Seddin were at least partly foreign-born, their status tied to their ability to mobilize distant connections.

This pattern mirrors findings from other parts of Europe, such as the Lech Valley in southern Germany, where isotope studies have shown that high-status women were often migrants. Taken together, these studies depict a Bronze Age world far more fluid, mobile, and interconnected than once assumed.

Related Research

* Knipper, C., Mittnik, A., Massy, K., et al. (2017). Female exogamy and gene pool diversification at the transition from the Final Neolithic to the Early Bronze Age in central Europe. PNAS, 114(38), 10083–10088. https://doi.org/10.1073/pnas.1706355114

* Frei, K. M., Mannering, U., Kristiansen, K., et al. (2015). Tracing the life story of a Bronze Age woman from Egtved, Denmark. Scientific Reports, 5, 10431. https://doi.org/10.1038/srep10431

* Price, T. D., Frei, K. M., & Frei, R. (2015). Strontium isotopes and human mobility: A geochemical approach to archaeology. Annual Review of Anthropology, 44, 217–231. https://doi.org/10.1146/annurev-anthro-102214-013854

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A New Look at the Evolution of the Human Brain

One of the enduring questions in human evolution is why certain cognitive conditions—autism spectrum disorder (ASD) among them—appear far more common in Homo sapiens than in other primates. A new paper in Molecular Biology and Evolution tackles this puzzle from a fresh angle, linking cell-type evolution in the neocortex to the genetics of autism.

“The most abundant type of neocortical neurons—layer 2/3 intratelencephalic excitatory neurons—has evolved exceptionally quickly in the human lineage compared to other apes,” Starr and Fraser report.

This finding suggests a remarkable trade-off: the same changes that may have helped build the uniquely human brain could also have increased our vulnerability to autism.

Why Layer 2/3 Neurons Matter

The human neocortex contains an extraordinary diversity of neurons. Starr and Fraser analyzed single-nucleus RNA sequencing data from multiple primate species to track how different cell types changed over time. They discovered a consistent pattern: more common neuronal cell types evolved more slowly, likely because mutations in them carry a higher cost.

But one group stood out. Layer 2/3 intratelencephalic (L2/3 IT) neurons, which connect different regions of the cortex and underpin higher-order cognition, evolved much faster in the human lineage than expected.

“This accelerated evolution was accompanied by dramatic down-regulation of autism-associated genes, which was likely driven by polygenic positive selection specific to the human lineage,” the authors write.

Evolution’s Double-Edged Sword

Why would natural selection favor changes that increase autism risk? Starr and Fraser point to several possibilities. Many autism-linked genes also influence brain development speed. Humans have an unusually slow postnatal brain development compared to other primates, which may have allowed more complex learning—including language—to take root.

They also note that changes in L2/3 IT neurons overlap with genes tied to schizophrenia, hinting at a broader evolutionary reshaping of the human brain’s wiring and plasticity.

“Our analysis suggests that natural selection on gene expression may have increased the prevalence of ASD, and perhaps also schizophrenia, in humans,” the paper states.

Testing the Hypothesis in the Lab

To rule out non-genetic explanations, the team used human–chimpanzee hybrid cortical organoids to measure allele-specific expression in identical environments. This experiment showed a consistent bias: human alleles of autism-linked genes were expressed at lower levels than chimpanzee alleles.

This pattern strongly supports lineage-specific natural selection rather than random drift.

Rethinking Human-Specific Disorders

From an anthropological perspective, these findings suggest that conditions often framed purely as “disorders” may instead be byproducts of the same evolutionary pressures that gave rise to our species’ extraordinary cognition. Rather than being uniquely pathological, autism’s prevalence might reflect a legacy of how our brains evolved to learn slowly, integrate information across cortical regions, and develop complex social and linguistic capacities.

Where This Leaves Anthropology and Archaeology

For anthropologists and archaeologists, the study highlights the importance of integrating genetics, neuroscience, and evolutionary theory to understand human uniqueness. Just as stone tools and symbolic artifacts offer windows into our ancestors’ behavior, neuronal cell types and their gene expression profiles may hold keys to our cognitive past.

Summary for Social Media (235 characters):

New research links autism’s high prevalence to rapid evolution of a key human neuron type. The same changes that built our unique cognition may have increased neurodiversity. #Anthropology #HumanEvolution #Neuroscience

Related Research:

* Human-accelerated regions and autism: Doan, R. N. et al. (2016). Molecular Psychiatry, 21(1), 80–88. https://doi.org/10.1038/mp.2015.142

* Human-specific gene expression shifts in the brain: Liu, X. et al. (2016). Nature, 530(7590), 171–174. https://doi.org/10.1038/nature16505

* Neocortical neuron diversity across species: Bakken, T. E. et al. (2021). Nature, 598(7879), 111–119. https://doi.org/10.1038/s41586-021-03465-8

* Human–chimp hybrid organoids for evolutionary studies: Gokhman, D. et al. (2021). Nature, 592(7853), 277–283. https://doi.org/10.1038/s41586-021-03498-z

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When archaeologists discuss the skills that allowed Homo sapiens to eclipse other hominins, they often cite symbolic behavior, complex tools, or language. But beneath these visible traits lies something less tangible: the capacity to focus. Paying attention — selectively, deeply, and flexibly — shapes how humans plan, hunt, and cooperate. A recent paper in the Journal of Archaeological Science explores how this trait may have emerged from subtle differences in neurogenetics among modern humans, Neanderthals, and Denisovans.

Genes as Clues to Ancient Minds

Marlize Lombard, a cognitive archaeologist at the University of Johannesburg, set out to examine which genes linked to attention in Homo sapiens show differences in the Neanderthal and Denisovan genomes. Ancient DNA now provides full genome sequences of both extinct relatives, allowing researchers to ask new questions about their cognition.

“Paying attention in complex ways is one of the things that humans do differently from all animals today,” Lombard notes. “The question is how far back this ability goes — and whether our cousins shared it.”

By sifting through published datasets, Lombard identified 180 genes associated with attention in Homo sapiens that differ from those in Neanderthals and Denisovans. Eighteen were highly expressed in specific brain regions, including the brainstem, cerebellum, amygdala, basal ganglia, white matter, and thalamus. Many of these regions are typically considered “ancient” brain structures, not the obvious centers of higher cognition.

“These subcortical regions, along with the thalamus, are implicated in the evolution of human attention and deserve more focused study,” Lombard argues.

The Surprising Role of the “Reptile Brain”

In modern neuroscience, the brainstem and cerebellum are often cast as housekeeping centers of movement, balance, and automatic processing. Yet recent research shows they also regulate sensory integration and attention. Clinical neuroscientist Samantha Abram, who studies psychosis at the University of California San Francisco, finds the overlap striking.

“I was struck by the fact that this paper found the cerebellum and brainstem were huge contributors to the evolution of attention,” Abram says. “It’s another line of evidence that these areas play a role in human thinking, not just basic processing.”

The implication is that Homo sapiens may have developed faster, more efficient “relay hubs” for attention compared to Neanderthals and Denisovans — a neurological advantage that could ripple out into planning, tool use, and social learning.

Limits and Caution

Other scholars urge caution. Cedric Boeckx, an evolutionary neuroscientist at the Catalan Institution for Research and Advanced Studies, emphasizes that genetic differences do not automatically translate to behavioral differences.

“Having ancient genomes is a valuable source of information, but it has to be used very wisely,” Boeckx says. “There isn’t a direct link between genotype and phenotype.”

Without experimental evidence, such as gene-function studies in model organisms, the cognitive effects of these mutations remain speculative. But Boeckx agrees that highlighting subcortical areas broadens the conversation about hominin cognition beyond the cerebral cortex.

From Genes to Technologies

Even with caveats, Lombard’s approach underscores how internal brain circuitry may have supported the outward behaviors archaeologists study. If attention networks in Homo sapiens became more robust, they could have enabled longer periods of focus, finer motor control, or more elaborate social coordination. Lombard’s previous work has already identified 48 attention-related genes expressed differently in the precuneus, a region associated with self-awareness and spatial reasoning.

As Lombard notes, these hidden aspects of the brain may hold the keys to understanding why Homo sapiens produced complex symbolic traditions, long-range trade, and intricate toolkits, while other hominins faded.

“The goal,” Lombard explains, “is to assess these brain areas’ potential for telling us something new about how the human mind evolved its capacity for paying attention.”

Related Research

* Gunz, P., et al. (2019). Neandertal introgression sheds light on modern human brain evolution. Nature, 571(7763), 512–516. https://doi.org/10.1038/s41586-019-1366-5

* Kochiyama, T., et al. (2018). Reconstructing the Neanderthal brain using computational anatomy. Scientific Reports, 8(1), 6296. https://doi.org/10.1038/s41598-018-24331-0

* Neubauer, S., et al. (2018). The evolution of modern human brain shape. Science Advances, 4(1), eaao5961. https://doi.org/10.1126/sciadv.aao5961

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Across the rolling lowlands of southern Britain lie strange hills of bone and soil. They are not barrows or burial mounds but middens—prehistoric rubbish heaps built from the remnants of enormous communal feasts. New isotope research suggests these mounds were more than places to discard leftovers. They were hubs of mobility, identity, and social power at the end of the Bronze Age.

Middens as social landscapes

Middens are not subtle. Potterne in Wiltshire covers an area the size of five football pitches, its layers dense with charred bone and broken pottery. East Chisenbury rises like a long, low mound only ten miles from Stonehenge, holding the remains of hundreds of thousands of animals. At Runnymede, cattle bones dominate the soil near the Thames.

For decades, archaeologists suspected these accumulations reflected large-scale gatherings. Yet it was unclear just how far the people—or their livestock—had come to take part.

“Each midden had a distinct makeup of animal remains, with some full of locally raised sheep and others with pigs or cattle from far and wide,” explains Dr. Carmen Esposito, lead author of the new study, conducted at Cardiff University and now at the University of Bologna.

The research, published in iScience, examined six middens in Wiltshire and the Thames Valley. Using multi-isotope analysis, the team traced the geographic origins of the animals slaughtered at each site. The findings sketch a portrait of Bronze Age Britain in motion.

A feast of regions

Potterne stands out as a place of pork. Its pigs came from an unusually broad catchment, extending into northern England. This is not the signature of a single farm supplying meat, but of multiple groups converging on a shared ritual center.

Runnymede tells a different story. Here cattle, not pigs, dominate, and their isotopic signatures show origins far beyond the immediate region. East Chisenbury, in contrast, looks more local. Sheep form the overwhelming majority of bones, and the isotope values indicate animals raised in the surrounding landscape rather than imported from afar.

“We believe this demonstrates that each midden was a lynchpin in the landscape, key to sustaining specific regional economies, expressing identities and sustaining relations between communities during this turbulent period,” says Esposito.

The period in question—roughly 3,000 years ago—marked a time of upheaval. The value of bronze declined, trade networks shifted, and communities turned increasingly to farming. Yet the middens show that large gatherings persisted, perhaps becoming more important precisely because they helped knit fractured societies together.

Bones as travelogues

Multi-isotope analysis allows archaeologists to track animals across time and space. Because local geology leaves distinct chemical signatures in water, plants, and soil, those markers end up in the teeth and bones of animals and humans. Centuries later, researchers can use this geochemical map to identify where individuals were raised.

“At a time of climatic and economic instability, people in southern Britain turned to feasting—there was perhaps a feasting age between the Bronze and Iron Age,” says Professor Richard Madgwick, a co-author of the study at Cardiff University.

These events were not merely about consumption. They created obligations and alliances, forged identities, and reaffirmed social structures. The middens themselves became monuments—physical testaments to gatherings that may have rivaled anything seen again in Britain until medieval fairs.

“The scale of these accumulations of debris and their wide catchment is astonishing and points to communal consumption and social mobilization on a scale that is arguably unparalleled in British prehistory,” Madgwick adds.

Beyond the Bronze Age

The study complicates earlier ideas of an isolated and fragmented Late Bronze Age. Instead, it shows a patchwork of interconnected communities, each using feasting to anchor social and economic networks. Potterne, Runnymede, and East Chisenbury were not interchangeable—they played complementary roles in a wider system of movement, trade, and ritual.

These findings also underscore how material discarded thousands of years ago can retain vital information. In the bones of pigs and sheep lie stories of human travel, social cohesion, and the shifting meaning of meat at a pivotal moment in Britain’s past.

Related Research

* Madgwick, R., Lamb, A. L., Sloane, H., Nederbragt, A. J., Albarella, U., & Parker Pearson, M. (2019). Multi-isotope analysis reveals that feasts in the Stonehenge environs involved livestock from across Britain. Science Advances, 5(3), eaau6078. https://doi.org/10.1126/sciadv.aau6078

* Parker Pearson, M. (2012). Stonehenge: Exploring the Greatest Stone Age Mystery. Simon & Schuster.

* Sharples, N., & Parker Pearson, M. (1997). Between Land and Sea: Excavations at Dun Vulan, South Uist. Society of Antiquaries of Scotland.

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A Forgotten Landscape

For decades, archaeologists pictured the heart of the Iberian Peninsula—the vast central plateau known as the Meseta—as a barren expanse bypassed by the first Homo sapiens. After Neanderthals disappeared, it was assumed that this cold and arid interior remained nearly empty until modern humans returned near the end of the Last Glacial Maximum.

A new study from the rock shelter of Abrigo de la Malia in Guadalajara upends that assumption. Dating to between 36,200 and 26,260 years ago, the site preserves faunal remains that capture the lives of hunters who not only ventured into the Meseta but returned often enough to leave a record stretching over 10,000 years.

“The zooarchaeological and taphonomic evidence documents short but recurrent occupations over at least 10,000 years,” the authors write. “This pattern demonstrates that climatic deterioration during the Early Upper Paleolithic did not significantly alter the settlement patterns or subsistence strategies of Homo sapiens.”

What the Bones Reveal

The Malia assemblage is dominated by medium and large ungulates—red deer, wild horses, bison, and chamois. Cut marks and bone fractures show that humans, not carnivores, were the primary agents of processing. The hunters skinned, butchered, and cracked bones for marrow.

“Taphonomic data suggests primary and almost exclusive anthropic processing of medium and large-sized ungulates, from skinning to marrow extraction”

These patterns suggest the site was not a permanent home but a recurrent hunting camp. Groups likely stopped at Malia to process carcasses after nearby kills, leaving behind bones, lithics, and traces of hearths before moving on.

Climate Windows and Human Resilience

Malia’s sediments preserve ecological shifts. Around 35,000 years ago, climatic amelioration in the Submediterranean zone boosted herbivore biomass, creating what researchers describe as “ecological windows of opportunity” that drew human groups inland.

As conditions worsened, with forests giving way to colder open landscapes, humans adapted by continuing to target reliable game. The resilience of these groups contradicts older models that portrayed the plateau as uninhabitable during the harsh climate of Marine Isotope Stage 3.

Challenging Old Narratives

Previous research focused on coastal refuges, where rich archaeological layers painted a picture of Upper Paleolithic life concentrated along the Cantabrian, Atlantic, and Mediterranean margins. By contrast, sites in the Meseta seemed scarce, reinforcing the idea of a depopulated heartland.

Malia forces a reassessment. Its evidence shows that early Homo sapiens were capable of exploiting upland, forested, and grassland environments—even under deteriorating climates.

“Malia allows us to characterize human behavior in the early Upper Paleolithic and provides insight into the resilience of the first Homo sapiens to successfully colonize challenging and resource-scarce territories”

A Plateau Not Empty, but Alive

Malia joins a growing list of sites suggesting the Meseta was never a true void. Short-term occupations like those at Los Enebrales and Peña Capón hint at repeated visits by hunting groups. Seen together, they suggest a mosaic of mobility strategies: sometimes seasonal camps, sometimes task-specific stopovers, always tied to the rhythms of climate and prey.

Why It Matters

The discovery repositions central Iberia within broader debates about how early modern humans spread across Europe. It suggests that their colonization strategies were not limited to resource-rich coasts but extended into demanding interior environments.

This resilience adds nuance to the story of human dispersal: Homo sapiens were not simply opportunistic invaders of easy landscapes but skilled hunters able to extract sustenance from difficult ecologies.

Related Research

* Alcaraz-Castaño, M., et al. (2017). “The human settlement of Central Iberia during MIS 2: new technological, chronological and environmental data from the Solutrean workshop of Las Delicias.” Quaternary International, 431, 104–124. https://doi.org/10.1016/j.quaint.2015.11.001

* Vidal-Cordasco, M., et al. (2022). “Ecological opportunities and the persistence of Upper Paleolithic populations in Iberia.” Quaternary Science Reviews, 286, 107523. https://doi.org/10.1016/j.quascirev.2022.107523

* Lombera-Hermida, A., et al. (2021). “Subsistence and settlement strategies at Cova Eirós during the Upper Paleolithic.” Journal of Archaeological Science: Reports, 38, 103061. https://doi.org/10.1016/j.jasrep.2021.103061

* Sanchis, A., et al. (2023). “Short-term occupations in the Upper Paleolithic: faunal insights from Cova de les Malladetes.” Quaternary International, 685–686, 69–84. https://doi.org/10.1016/j.quaint.2023.03.005

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