Evolutionary Insights by Anthropology.net

In the heart of ancient China’s political machinery, where emperors ruled from Chang’an and armies marched from loess plains, a quieter but no less crucial revolution was taking place in the soil. Beneath the feet of palace courtiers and farmers alike, changes in agricultural practice were unfolding that would sustain one of the most enduring empires in Chinese history: the Han Dynasty.

Recent research led by Jingwen Liao and colleagues from Leiden University and Fudan University used stable isotope analysis to trace the long-term evolution of farming strategies in the Guanzhong Basin—a region that not only served as the Han capital's granary, but also as a climate archive written in millet.

Digging into the Tombs of Farmers

The research team analyzed carbon (δ13C) and nitrogen (δ15N) isotope ratios in common millet (Panicum miliaceum) and foxtail millet (Setaria italica) recovered from five archaeological sites: four Han Dynasty tombs and one Late Neolithic site. In the Han tombs, pottery granaries buried with the dead still contained husks of the grains that fed the living.

This gave the researchers a rare chance to compare Neolithic and Han-era millet agriculture directly. The isotopic values in these crops serve as chemical fingerprints of the conditions in which they were grown, including water availability and soil fertility.

"Compared to the Late Neolithic period, the δ15N values of common and foxtail millets in the Han capital and its surrounding areas increased by 6.5‰ and 2.7‰ respectively, indicating an intensification of fertilization strategies," the authors report.

Farming in a Changing Climate

The Han Dynasty unfolded during a time of environmental transition. Monsoon rainfall was gradually decreasing, and winters were cooling. Archaeological soils in the Guanzhong Basin show a shift toward drier conditions after about 3000 years ago. Yet isotope values indicate that Han farmers were adapting. Their fields were not becoming less productive.

The drop in δ13C values during the Han period suggests increased water input during millet cultivation. This aligns with historical accounts of extensive canal systems like the Longshou and Lingzhi Canals, engineered to keep farmland irrigated despite shifting rainfall.

Pig Pens and Privies: Ancient Composting Systems

One innovation that stands out is the fusion of household waste streams into usable fertilizer. Historical texts and tomb models indicate that latrines and pigsties were often built side by side. Waste from both humans and animals was collected in compost pits and then applied to fields. The Han manual Fan Shengzhi Shu even recommended manure from pig pens as especially valuable.

"The purpose of such structures was to mix pig manure, human manure, and feed scrap to obtain well-decomposed manure with higher organic content," note the authors.

Animal husbandry expanded during the Han, with household pig-raising becoming widespread. That meant more accessible fertilizer for smallholder farmers, who could also supplement it with plant ash, silkworm waste, and even river mud.

Farmers, Elites, and the Political Economy of Soil

The tombs studied likely belonged to landlords or minor aristocrats, whose wealth derived from the land and the labor that worked it. Because agriculture was taxed in-kind, elites had strong incentives to maximize yields. Better tools, crop rotation, and organized irrigation were part of a systemic push toward intensive farming.

What this study makes clear is that intensification wasn’t simply a response to climate stress or technological availability. It was also tied to the political structure of the empire—a system that demanded surplus and stability, and therefore innovation in how land was managed.

"The success of intensive irrigation and fertilization strategies in the Han Dynasty not only fostered advances in farmland management practices but also helped elites accumulate more wealth," the study concludes. "This may have accelerated social divisions and unequal economies within the empire."

Isotopes and the Memory of Soil

The nitrogen isotope signature of millet provides a kind of soil memory, revealing how deeply fertilization was embedded in Han agriculture. Unlike historical texts, which emphasize ideals, isotope data capture everyday practice. The study documents a shift from modest manuring in the Neolithic to intensive fertilization in the Han era.

In this way, ancient crops become not just remnants of past meals, but archives of human ingenuity. They show how agricultural knowledge was transmitted, adapted, and institutionalized across centuries.

A Broader Agricultural Legacy

The researchers argue that the Guanzhong Basin should be seen as more than just a political center. It was a laboratory of early imperial agronomy. Stable isotope analysis, especially when combined with historical records and archaeological data, opens a path to reconstructing ancient land use with precision.

Yet the story is incomplete. Millet is a C4 crop, which responds differently to water conditions than wheat or rice. Expanding isotopic studies to C3 plants will be essential to better understand how water management varied across the empire. For now, millet offers the clearest window into how one of the world’s great early empires fed itself—and how its people responded, with persistence and invention, to the challenges of climate and rule.

Further Reading and Related Research

* Christensen, B. T., Jensen, J. L., Dong, Y., Bogaard, A. (2022). Manure for millet: Grain δ15N values as indicators of prehistoric cropping intensity of Panicum miliaceum and Setaria italica. Journal of Archaeological Science, 139, 105554. https://doi.org/10.1016/j.jas.2022.105554

* Kanstrup, M., Holst, M. K., Jensen, P. M., Thomsen, I. K., Christensen, B. T. (2014). Searching for long-term trends in prehistoric manuring practice: δ15N analyses of charred cereal grains from the 4th to the 1st millennium BC. Journal of Archaeological Science, 51, 115–125. https://doi.org/10.1016/j.jas.2013.04.018

* Allen, E., Yu, Y., Yang, X., et al. (2022). Multidisciplinary lines of evidence reveal East/Northeast Asian origins of agriculturalist/pastoralist residents at a Han dynasty military outpost in ancient Xinjiang. Frontiers in Ecology and Evolution, 10, 932004. https://doi.org/10.3389/fevo.2022.932004

* Ma, M., Dong, J., Yang, Y., et al. (2023). Isotopic evidence reveals the gradual intensification of millet agriculture in Neolithic western Loess Plateau. Fundamental Research. https://doi.org/10.1016/j.fmre.2023.06.007

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

What makes Homo sapiens tall and metabolically demanding compared to our primate cousins? Scientists have long attributed these traits to changes in diet, lifestyle, and brain size, but recent work suggests a deeper molecular story—one that begins with a single mutation, likely more than half a million years old.

A Mutation in the Mitochondria's Metabolic Machinery

In a study published in Cell Genomics, researchers identified a regulatory genetic variant known as rs34590044-A that appears to have co-influenced both height and basal metabolic rate (BMR) in anatomically modern humans. The variant boosts the activity of a mitochondrial gene, ACSF3, which is involved in breaking down essential amino acids, particularly threonine—a key component of meat-heavy diets.

"The human-specific rs34590044-A allele can upregulate the expression of ACSF3 compared to the ancestral C allele," the authors reported, adding that this enhanced expression helps avoid buildup of the toxic metabolite methylmalonic acid (MMA), which can impair mitochondrial function.

This small change in the genome, likely under positive selection for the past 20,000 years, has been tied to two seemingly unrelated human traits: greater height and increased baseline energy expenditure.

Energy Demands of a Taller Species

Compared to our closest relatives—chimpanzees, bonobos, and gorillas—Homo sapiens are about 30 centimeters taller and have a BMR up to 50% higher, even when adjusted for body mass. The metabolic implications are enormous. Taller bodies require more energy not just for growth but also for thermoregulation and maintenance.

The research team analyzed genetic data from over 450,000 individuals in the UK Biobank and found a strong genetic correlation between BMR and height. They identified more than 6,000 genetic variants likely influencing both traits. Among them, the ACSF3 variant stood out.

Laboratory experiments using mouse models and human cell lines revealed that increased expression of ACSF3 improved mitochondrial activity, especially when animals were fed a threonine-rich diet. This not only enhanced energy production but also supported bone growth—suggesting that the metabolic and skeletal traits of modern humans are intertwined at the molecular level.

Ancient Diets, Modern Physiology

The evolutionary story doesn’t stop at genes. The ACSF3 mutation likely gained an advantage in humans consuming more animal protein. Essential amino acids like threonine are scarce in plant-based foods but plentiful in meat. Enhanced processing of these amino acids would have supported the energy-intensive physiology of a species with large brains, long legs, and high reproductive costs.

"Our findings support the idea that ACSF3 functions as a molecular bridge between nutrition and the emergence of key human traits," the study notes.

Data from ancient genomes back this up. The frequency of the rs34590044-A variant surged in European populations during the past 5,000 years, coinciding with major shifts in diet and mobility brought by pastoralist groups like the Yamnaya. The allele is now common in Europe, particularly in Britain.

A Window Into Our Adaptive Past

The story of ACSF3 shows how evolution often works through small molecular tweaks with big downstream effects. By enabling efficient metabolism of protein-rich foods, this single variant may have helped early humans grow taller, sustain larger brains, and thrive in new environments.

This research adds to a growing list of genetic changes shaped by dietary transitions: lactase persistence for digesting milk, amylase copy number variation for starch-rich diets, and FADS1 variants influencing fatty acid synthesis in farming populations. Together, they map out a genomic record of how food has sculpted the human body.

"The evolutionary history of Homo sapiens is as much a story of what we ate as where we walked."

Related Research

* Llamas, B., et al. (2021). From the cradle of humanity to the edge of the world: Ancient genomics and the prehistoric dispersal to Oceania. Nature, 592, 583–589. https://doi.org/10.1038/s41586-021-03236-5

* Perry, G. H., et al. (2007). Diet and the evolution of human amylase gene copy number variation. Nature Genetics, 39(10), 1256–1260. https://doi.org/10.1038/ng2123

* Mathieson, I., et al. (2015). Genome-wide patterns of selection in 230 ancient Eurasians. Nature, 528, 499–503. https://doi.org/10.1038/nature16152

* Enard, W., & Paabo, S. (2004). Comparative primate genomics and the evolution of human biology. Science, 306(5699), 1120–1123. https://doi.org/10.1126/science.1103936

* Fan, S., et al. (2025). An ancient regulatory variant of ACSF3 influences the coevolution of increased human height and basal metabolic rate via metabolic homeostasis. Cell Genomics, 5, 100855. https://doi.org/10.1016/j.xgen.2025.100855

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

In the sun-drenched soil of eastern Spain, where citrus groves meet ancient ruins, archaeologists have long chronicled the region's complex past. But bones often speak when texts fall silent. Now, DNA extracted from 12 individuals buried in cemeteries across Valencia has revealed a hidden history of cultural suppression and demographic transformation. The study, led by Gonzalo Oteo-García and colleagues, shows how centuries of coexistence between Europe and North Africa were violently severed in the 17th century—and how their echoes lingered in the genomes of the dead until that point.

Layers of Ancestry Beneath Christian and Islamic Stones

Through high-resolution sequencing of ancient genomes dating from the 3rd to the 17th century CE, researchers traced the region's complex population history across Roman, Islamic, and Christian eras. What emerged was the genomic footprint of a multicultural past, slowly effaced by war, conversion, and expulsion.

Among the most telling finds were two individuals buried in the same pit in Gandía—a man and his daughter. Their burial dates to around the time of the Islamic conquest of Iberia (711 CE), but their DNA tells a story of mixed ancestry. The father's genome carries significant North African ancestry, while the daughter's does not, indicating intermarriage between North African and Iberian populations within a single generation.

“This admixture wasn't just political or cultural,” the researchers note. “It was deeply personal and familial.”

Across five Islamic-period burials from Vall d’Uixó, the team found a consistent pattern of mixed North African and Iberian ancestry. These individuals likely belonged to the Muladís—local converts to Islam who embodied centuries of integration. Their genomes showed signs of both western Mediterranean and Levantine roots, with some carrying haplogroups common in North Africa today.

The Sudden Vanishing of Genetic Diversity

The turning point came in the early 1600s. Following rising tensions, forced conversions, and increasing restrictions, King Philip III of Spain ordered the expulsion of the Moriscos—Muslims who had converted to Christianity under duress. Historical records describe the departure of hundreds of thousands. What the genomes reveal is the scale of that disappearance.

Two Christian-period individuals buried in Valencia before the expulsion still bore substantial North African ancestry. But by the 17th century, that signal vanishes. One man, GOG60, shows no trace of it. His genome aligns squarely with modern Spanish populations.

“The genetic bridge between Europe and North Africa, visible for centuries, collapses abruptly after 1609 CE,” the study finds.

A contrasting case is GOG59, a man of clear North African descent buried with iron shackles around his leg. His remains suggest he was enslaved during one of the many Christian raids on the Barbary Coast. His DNA clusters closely with present-day Moroccan Berbers.

A Genetic Displacement with Transatlantic Echoes

One paradox the study addresses is the presence of North African ancestry in modern South American populations. Spanish colonial authorities barred Moriscos from emigrating, fearing divided loyalties. But the high levels of Maghrebi ancestry in Latin America suggest many Moriscos left Europe before the expulsion, carrying their genomes—and cultural legacies—across the Atlantic.

“The Iberian emigrants who settled the Americas carried more North African ancestry than is found in Spain today,” the authors argue.

Echoes in Bone and Blood

This study, published in Genome Biology, not only reconstructs a hidden demographic history but also foregrounds how ethnic cleansing shapes the genomic record. Despite centuries of convivencia in medieval Spain, the forced removal of Moriscos disrupted a stable, hybrid population, leaving little genetic trace in today's Valencian gene pool.

In the ruins of rural maqbaras and under the stones of urban churches, the DNA of the departed preserves a record of diversity lost. The cemeteries may have been forgotten. But in the silence of their bones, the memory of expulsion persists.

Further Reading and Related Research

* Silva, M., et al. (2021). Biomolecular insights into North African-related ancestry, mobility and diet in eleventh-century Al-Andalus. Scientific Reports, 11(1), 18121. https://doi.org/10.1038/s41598-021-97339-5

* Olalde, I., et al. (2019). The genomic history of the Iberian Peninsula over the past 8000 years. Science, 363(6432), 1230–1234. https://doi.org/10.1126/science.aav4040

* Rodríguez-Varela, R., et al. (2024). Five centuries of consanguinity, isolation, health, and conflict in Las Gobas: a northern medieval Iberian necropolis. Science Advances, 10(35), eadp8625. https://doi.org/10.1126/sciadv.adp8625

* Silva, M., et al. (2021). North African-related ancestry in medieval and early modern Spain: Insights from ancient DNA. Nature Communications, 12(1), 4166. https://doi.org/10.1038/s41467-021-24339-z

* Botigué, L. R., et al. (2013). Gene flow from North Africa contributes to differential human genetic diversity in southern Europe. Proceedings of the National Academy of Sciences, 110(29), 11791–11796. https://doi.org/10.1073/pnas.1306223110

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

he Tangier Peninsula sits at a geologic and cultural hinge. On maps, it's a narrow wedge of land pressing into the Strait of Gibraltar, with Europe just a short ferry ride to the north. But from 3000 to 500 BCE, this peninsula was more than a waystation. It was a ritual landscape shaped by the living and the dead.

Recent archaeological work—led by Hamza Benattia, Jorge Onrubia-Pintado, and Youssef Bokbot—has brought the peninsula's past into sharper focus. Their excavations and GIS analysis reveal a once-thriving landscape of cemeteries, painted rock shelters, and standing stones, challenging long-standing assumptions about North Africa's role in the prehistoric Mediterranean.

A Complex Ritual Geography

Between the third and first millennia BCE, the Tangier Peninsula hosted a surprising diversity of burial practices: pit graves, hypogea, tumuli, and stone-lined cists. These were not isolated phenomena. Instead, they were part of a broader network of symbolic and territorial practices, often concentrated at high points near ancient routes.

One of the most striking findings comes from Daroua Zaydan. Here, a single cist burial—constructed from upright slabs capped with a heavy stone—was radiocarbon dated to ca. 2000 BCE. It is the first such date for a cist in northwestern Africa. The grave was found on a modest hill near a long-silted bay, alongside scattered bones and flint flakes. Though modest, this tomb signals a milestone for regional chronology.

"This marks the first radiocarbon dated cist burial in northwestern Africa," write the authors. "It provides a terminus post quem for a burial tradition often assumed to be older but previously undated."

Burial Traditions Across Time and Terrain

Cist burials, like the one at Daroua Zaydan, were not unique to Morocco. Similar tombs exist across the Iberian Peninsula, often grouped into cemeteries on hilltops or beside ancient roads. But in Tangier, they take on local signatures. Some contain ochre, tortoiseshell, or copper awls. Others are empty, perhaps cenotaphs, echoing Iberian precedents.

Hypogea—rock-cut tombs—appear in the early first millennium BCE. These subterranean chambers, often reused across generations, reflect Mediterranean influences, likely tied to Phoenician contact. Yet they appear alongside older traditions, suggesting a layered ritual continuity rather than abrupt replacement.

And then there are the tumuli: stone mounds sometimes topped by megaliths. Some are solitary; others cluster into hilltop cemeteries. At Mzoura, 176 standing stones form a massive circle around a central mound, reaching five meters in height. The site, though only partially excavated, hints at ceremonial functions tied to memory, territory, and perhaps kingship.

Rock Art and Symbolic Space

The ritual landscape of Tangier was not limited to burial. Painted rock shelters—some featuring dots, grids, and anthropomorphic forms—dot the peninsula. At sites like Magara Sanar, red and white pigments were used to create compositions whose meanings remain opaque but whose placement suggests spiritual or communal significance.

Standing stones appear near routes and crossroads, as at Oued Ksiar, where cist cemeteries crown several hills. Their orientation and location suggest not just boundary markers, but places where paths, people, and stories converged.

"These were not isolated shrines," the authors note, "but integral components of a larger ritualized terrain."

Mediterranean Threads, African Roots

What emerges from this research is a vivid, deeply textured image of late prehistoric life in northwestern Africa. Long dismissed in favor of Roman ruins or Nilotic splendor, the Tangier Peninsula turns out to be a key locus of cultural interaction. Its cemeteries and rock art show echoes of both Saharan and Iberian styles. Its burial practices shift slowly over time, absorbing new elements while maintaining older forms.

The authors suggest that this mosaic of traditions reflects not fragmentation but connectivity. The peninsula, after all, was not a periphery but a junction—linking sea and land, Africa and Europe, desert and forest.

"The funerary and symbolic landscapes of Tangier demonstrate a persistent and evolving dialogue between local traditions and trans-regional networks," they conclude.

And so the stones speak—not just of death, but of belonging, identity, and deep time. Beneath the hills and in the hollows of painted caves, the ancestors of Tangier left more than bones. They left a record of how they saw the world.

Further Reading and Related Research

* González-Toraya, L., et al. (2010). La necrópolis de Loma del Puerco (Chiclana de la Frontera, Cádiz): nuevas perspectivas para el estudio del Bronce Final en el Suroeste peninsular. Mainake, 32, 231–276.

* Lillios, K. T. (2015). The Archaeology of the Iberian Peninsula: From the Paleolithic to the Bronze Age. Cambridge University Press. https://doi.org/10.1017/CBO9781139023815

* Broodbank, C., & Lucarini, G. (2019). The dynamics of Mediterranean Africa, ca. 9600–700 BC: An interpretive synthesis of knowns and unknowns. Journal of Mediterranean Archaeology, 32(2), 129–186. https://doi.org/10.1558/jmea.40187

* Benattia, H., Onrubia-Pintado, J., & Bokbot, Y. (2025). Cemeteries, rock art and other ritual monuments of the Tangier Peninsula, northwestern Africa, in wider trans-regional perspective (c. 3000–500 BC). African Archaeological Review. https://doi.org/10.1007/s10437-025-09621-z

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

In the shallow seafloor of Indonesia's Madura Strait, just off the coast of Java, an ancient landscape long hidden beneath the waves is beginning to come into focus. Through a combination of dredging operations, geological analysis, and fossil discovery, researchers have reconstructed a prehistoric river valley that once carried the Solo River eastward across what is now submerged Sundaland. And with it, they’ve uncovered an unexpected chapter in the life of Homo erectus.

A River Runs Through It

The Solo River has long been central to the story of Homo erectus in Southeast Asia. From the classic sites of Trinil and Ngandong, where early skullcaps reshaped our understanding of human origins, to the middle Pleistocene terraces that mark the species' last known traces, this river has yielded critical clues to our evolutionary past. But a new study, led by H.W.K. Berghuis and colleagues, shifts attention downstream—into the seabed itself.

In 2014–2015, dredging crews working to reclaim land near Surabaya extracted over 5 million cubic meters of sediment from the Madura Strait. What they found embedded in the sands stunned researchers: thousands of vertebrate fossils, including the skull fragments of Homo erectus. These remains represent the first direct evidence of Pleistocene hominin activity in submerged Sundaland.

“The fossils provide a rare and unprecedented insight into the Pleistocene vertebrate fauna of submerged Sundaland,” the authors wrote.

Careful geological analysis revealed that these fossils were embedded within a fluvial sediment sequence, part of a sand-filled paleovalley carved into marine clays. This valley was dated using optically stimulated luminescence (OSL) techniques to between 162,000 and 119,000 years ago—placing it squarely in the Marine Isotope Stage 6 (MIS6) glacial period, when sea levels were dramatically lower.

Fossils in a Drowned Landscape

The paleovalley fill preserves a complex transition: from terrestrial river sediments at its base to estuarine sandstones at its top, deposited as rising seas inundated the valley. This geological layering mirrors other known Homo erectus contexts on Java, but in this case, the fossiliferous layers lie underwater. What makes the discovery especially compelling is its temporal overlap with the Homo erectus fossils from Ngandong, previously considered the species' youngest population.

The sedimentological and faunal evidence suggests that this coastal lowland—at the time a vast grassland traversed by meandering rivers—was not only habitable but actively occupied by hominins. Among the fossil assemblage were bones bearing cut marks, evidence of butchery, and a suite of extinct and extant fauna, from water turtles to bovids.

“This earliest incisive stage of the Solo... is probably the equivalent of the lowest, partly preserved paleovalley of the Madura Strait north of Surabaya,” the team wrote, tying the submerged valley to broader patterns of fluvial incision during glacial periods.

Connecting Ngandong to the Coast

Berghuis and his co-authors draw a compelling link between the Madura Strait site and the better-known inland terraces of the Solo River. Both appear to have undergone similar cycles of incision and aggradation driven by glacial-interglacial sea-level fluctuations. The study suggests that during MIS6, the Solo River extended well beyond its present mouth, cutting across now-drowned plains to empty into a much more distant sea.

That coastal zone, rich in resources and ecological diversity, would have offered opportunities for Homo erectus populations to thrive. The river system connected upland and lowland environments, potentially serving as a corridor for dispersal—and perhaps, for interaction with other archaic hominins.

“The valley was probably cut during the preceding stage of falling sea level, in the run-up to the lowstand of MIS6,” the authors explain, anchoring their dating to a precise climatic moment.

Rethinking Isolation

One of the long-standing views in paleoanthropology has been that Homo erectus in Java persisted in isolation, marooned by rising seas. The Madura Strait discoveries challenge that assumption. They show Homo erectus was not only present in coastal environments during the late Middle Pleistocene but possibly adapted to a dynamic, shifting landscape shaped by repeated sea-level change.

Moreover, the rich bone assemblages suggest active subsistence behaviors more complex than once thought. Researchers documented signs of marrow extraction from bovids, a pattern more typically associated with later hominins. Whether these practices reflect independent innovation or contact with other groups remains an open question.

Toward a Submerged Prehistory

The drowned shelf of Sundaland has long been considered archaeologically silent. This research offers a new direction—both literally and conceptually. The ancient river valley now submerged under 30 meters of seawater might be one of many such features preserving vital chapters of hominin prehistory.

“This makes our discoveries truly unique,” Berghuis remarked in a related interview. “The fossils come from a drowned river valley, which filled up over time with river sand.”

As geologists and archaeologists continue to collaborate, sediment by sediment, we may find that the missing pieces of Southeast Asia’s human story lie offshore, in landscapes carved by ancient rivers and drowned by time.

Related Research

* Rizal, Y., Westaway, K. E., Zaim, Y., van den Bergh, G. D., et al. (2020). Last appearance of Homo erectus at Ngandong, Java, 117,000–108,000 years ago. Nature, 577(7792), 381–385. https://doi.org/10.1038/s41586-019-1863-2

* Joordens, J. C. A., et al. (2015). Homo erectus at Trinil on Java used shells for tool production and engraving. Nature, 518, 228–231. https://doi.org/10.1038/nature13962

* Louys, J., & Kealy, S. (2024). Faunal corridors and hominin dispersal routes in Pleistocene Sundaland. Quaternary Science Reviews, 318, 107171. https://doi.org/10.1016/j.quascirev.2023.107171

* Hilgen, F. J., et al. (2023). Age constraints on the Trinil H. erectus fossils and the implication for hominin evolution in Southeast Asia. Science Advances, 9(2), eadd3147. https://doi.org/10.1126/sciadv.add3147

* Brasseur, B., et al. (2011). Geochemical weathering patterns in the Pleistocene clays of eastern Java. Sedimentary Geology, 239(1–2), 51–66. https://doi.org/10.1016/j.sedgeo.2011.05.002

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

In the deep past, long before written records or monumental architecture, human groups took part in a migration that would come to define the edges of our species' range. From the icy expanses of North Asia to the farthest tip of South America, early humans embarked on a journey that would span 20,000 kilometers and thousands of years. A new genomic study, led by Elena Gusareva and colleagues from the GenomeAsia100K consortium, provides the clearest map yet of this extraordinary movement, revealing both the scope of ancient human adaptability and the hidden costs of isolation.

A map etched in DNA

By analyzing the genomes of 1,537 individuals across 139 ethnic groups in North Eurasia and the Americas, the research team reconstructed ancient migratory paths that once wound through Siberian tundra, over the Bering Land Bridge, and down the spine of the Americas. The project offers unprecedented resolution of how populations split, adapted, and declined across millennia.

One of the study's starkest revelations: all contemporary Indigenous populations of South America derive from just four ancestral groups—Amazonians, Andeans, Chaco Amerindians, and Patagonians—who branched off from a shared lineage in Mesoamerica roughly 13,900 to 10,000 years ago.

"Migration through the Isthmus of Panama acted like a funnel," the authors explain. "Once groups entered South America, they were immediately separated by geography, and thus by genetics."

That separation, over thousands of years, came at a cost. Unlike the genetic richness seen in Africa and Eurasia, the South American groups show signs of pronounced genetic bottlenecks: lower diversity, high homozygosity, and reduced variation in key immune system genes. This was especially true for isolated populations like the Kawésqar in Patagonia, whose ancestors made it to the southernmost tip of the continent.

Isolation and immune vulnerability

The Kawésqar, who once navigated the fjords of southern Chile in bark canoes, now carry some of the lowest genetic diversity recorded in any human group. Genomic data shows that their effective population size has shrunk by nearly 80% over the past 10,000 years. The causes were both environmental and demographic. The Andes, the Amazon, and the arid Chaco region all contributed to genetic isolation.

That isolation impacted health. Reduced variation in human leukocyte antigen (HLA) genes, which regulate immune responses, could help explain why Indigenous communities across the Americas have historically suffered disproportionately from infectious disease outbreaks introduced by outsiders.

"Founder effects and long-term population isolation appear to have eroded immunogenetic diversity," the authors note, raising the stakes for public health measures tailored to Indigenous needs.

Echoes from the north

While South American diversity constricted, the populations of North Eurasia show a very different story. The Kets and Nenets of West Siberia, once widespread, share ancestry with many northern Eurasian groups and contributed significantly to the gene pool of modern Siberians.

Meanwhile, Beringian populations like the Inuit and Koryaks reveal adaptations to Arctic life at the genetic level: variations linked to cold resistance, lipid metabolism, and even sensory perception. One gene, CPT1A, which plays a role in fat metabolism, appears to have been favored in Arctic groups despite being associated with metabolic disorders in other contexts. Such trade-offs underscore how evolution is shaped by local environments.

The genetic data also confirm what archaeological footprints in New Mexico and ancient bones in Patagonia have long suggested: that human arrival in the Americas predates the Ice-Free Corridor and follows a rapid dispersal along the Pacific coast.

The human cost of endurance

Migration to South America wasn't just long; it was also final. The narrow isthmus that allowed entry also restricted return. Once populations spread south, they remained genetically marooned.

"This migration wasn’t a highway. It was a one-way path into isolation," said one of the co-authors. "And over time, that isolation took a toll on genomic resilience."

Some groups like the Andean highlanders, who developed adaptations to low oxygen environments, show more robust genetic diversity, likely due to later regional growth during the spread of maize horticulture. But many others did not rebound.

A future for ancient lineages

The study doesn’t just reconstruct the past—it also carries urgent implications for the present. As Indigenous populations face ongoing threats from environmental degradation, climate change, and health disparities, the genomic insights offer a roadmap for medical and cultural preservation.

"Understanding how long-term isolation affects immune gene diversity can inform vaccine development, public health outreach, and conservation of vulnerable communities."

Crucially, the study also challenges the long-held assumption that Europe holds the bulk of human genetic diversity. Instead, much of that richness resides in Asia—and is now fading in parts of the Americas. Protecting it, researchers argue, is not only a matter of heritage, but of survival.

Related Research

* Moreno-Mayar, J. V., et al. (2018). Early human dispersals within the Americas. Science, 362(6419), eaav2621. https://doi.org/10.1126/science.aav2621

* Campelo Dos Santos, A. L., et al. (2022). Genomic evidence for ancient human migration routes along South America's Atlantic coast. Proc. Biol. Sci., 289(1980), 20221078. https://doi.org/10.1098/rspb.2022.1078

* Castro E Silva, M. A., et al. (2022). Population Histories and Genomic Diversity of South American Natives. Mol. Biol. Evol., 39(1), msab339. https://doi.org/10.1093/molbev/msab339

* Flegontov, P., et al. (2019). Palaeo-Eskimo genetic ancestry and the peopling of Chukotka and North America. Nature, 570(7760), 236–240. https://doi.org/10.1038/s41586-019-1251-y

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

Domestication as a Turning Point in Human Evolution

The domestication of plants and animals is often framed as a cornerstone of civilization. It’s the moment, we’re told, when our ancestors turned from the unpredictability of foraging to the structured stability of farming. Domestication allowed for permanent settlements, surplus food, the rise of states—and ultimately, the birth of what we call “history.”

But what if this story gets it backwards?

A growing number of archaeologists and evolutionary biologists now argue that domestication wasn’t simply something humans did to other species. Rather, it was something that happened between us—over generations, unconsciously, through evolutionary feedback loops in which both humans and other species co-evolved.

Three recent papers—two in Philosophical Transactions of the Royal Society B and one in PNAS—bring this radical reinterpretation into sharper focus. Taken together, they shift domestication from a narrative of human conquest to one of ecological entanglement.

A New Definition: Not Domination, but Co-evolution

In a provocative paper published in PNAS, evolutionary biologist Kathryn A. Lord and her colleagues propose a redefinition of domestication as an evolutionary process, rather than an intentional act of human control. According to their framework, species adapt to anthropogenic niches—the ecological spaces humans unintentionally or intentionally create.

“Domestication is not just about humans taming nature,” Lord explains. “It's about how species evolve in response to the environments we create.”

This means animals like free-ranging dogs or urban pigeons—long marginalized in discussions of domestication—may be more representative of the domestication process than previously thought.

Lord’s team introduces a spectrum of domestication, from species that adapt peripherally to human environments to those that become completely dependent on us. This model accounts for both the deliberate breeding of livestock and the evolutionary drift of animals that simply learned to live with us.

Unintentional Origins: Domestication Without Design

In a second paper, archaeobotanist Robert N. Spengler and collaborators press further. Their argument, published in Philosophical Transactions of the Royal Society B, contends that most domestication was unintentional.

“Domestication is the foundation of modern civilization,” says Spengler. “Understanding how it really happened—across species, regions, and millennia—reshapes our sense of what it means to be human today.”

Rather than viewing domestication as a singular invention, they propose that it unfolded gradually across generations as humans and species entered into increasingly tight co-dependencies.

The article challenges scholars to reconsider how archaeological evidence—such as grain size, seed dispersal traits, or animal morphology—is interpreted. Instead of looking for a single domestication “event,” we might better understand the process as a series of micro-adaptations.

Parallel Histories: Cereal Domestication Across Eurasia

A third study, also in Philosophical Transactions B, looks at one of the most iconic examples of domestication—grain agriculture. Rita Dal Martello and colleagues conducted a sweeping analysis of archaeological cereal grain data from across Eurasia.

They found something remarkable: the evolutionary traits we associate with domesticated cereals—such as increased grain size—emerged independently in multiple regions.

“Our findings highlight how similar evolutionary patterns emerged independently across Eurasia,” Dal Martello notes. “This suggests that domestication was not a singular event but a series of parallel processes influenced by various environmental and cultural factors.”

In other words, domestication didn't spread like a spark catching fire. It emerged repeatedly in different places under similar conditions—wherever humans and plants became entangled in each other's life cycles.

Toward a New Archaeology of Entanglement

These new frameworks compel archaeologists and anthropologists to rethink domestication not as the product of ancient genius, but as an evolutionary dialogue—an emergent outcome of long-term interaction.

As our species continues to alter the biosphere at an unprecedented scale—urbanizing ecosystems, redirecting evolution via CRISPR, and domesticating microbiomes—the stakes of understanding these deep-time relationships grow ever higher.

“The archaeological record offers essential insights into how long-term human-plant-animal relationships unfold,” says Spengler. “These lessons could inform more sustainable practices today and tomorrow.”

We didn’t just domesticate the dog or the wheat. In a sense, they domesticated us too.

Related Reading

* Zeder, M. A. (2012). The domestication of animals, Philosophical Transactions B

* Larson, G. et al. (2014). Current perspectives and the future of domestication studies, PNAS

* Arbuckle, B., & Makarewicz, C. (2009). The origins and spread of animal domestication, Journal of Anthropological Archaeology

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

Reconsidering the Prehistoric Dead of Northwest Africa

For decades, the prehistoric heritage of North Africa has lived in the shadow of its pharaonic and Roman successors. The sands of Egypt and ruins of Carthage dominate popular and scholarly imagination alike. But what if we turned west, to the windswept ridges and limestone caves of the Tangier Peninsula, where ancient communities carved their beliefs into rock, built cemeteries atop hills, and placed standing stones in deliberate alignment with terrestrial crossroads?

Recent work by Hamza Benattia, Jorge Onrubia-Pintado, and Youssef Bokbot sheds new light on the complex ritual life of this region between 3000 and 500 BCE. Their study, published in African Archaeological Review combines GIS mapping, radiocarbon analysis, and field excavation to reveal a dense mosaic of funerary monuments, symbolic structures, and art. It's a reminder that the Tangier Peninsula was not a cultural periphery but a hub of prehistoric innovation.

"It is a sad reality that the later prehistoric funerary and ritual landscapes of North Africa west of Egypt remain [...] the least widely known and understood in the Mediterranean region."

A Peninsula at the Edge of Continents

Geographically, the Tangier Peninsula is a geological and cultural hinge. It sits on the African side of the Strait of Gibraltar, where the Mediterranean kisses the Atlantic and where Europe lies only 14 kilometers away. This unique position shaped human activity for millennia. By analyzing known cemeteries and monuments alongside probable mobility corridors, the research team identified previously undocumented crossroads that anchored burial grounds and standing stones.

In the surrounding hills, they found everything from pit graves and hypogea to megalithic cists and tumuli. The use of ochre, placement of pottery, and inclusion of metal tools speak to ritual continuities and innovations across three millennia.

The First Dated Cist Grave in Northwest Africa

Among the team's most significant discoveries is the site of Daroua Zaydan. There, a solitary cist grave constructed of sandstone slabs revealed not just architectural consistency with Iberian burials but also radiocarbon-dated human remains. The date? Somewhere between 2119 and 1890 BCE.

"This marks the first radiocarbon-dated cist burial in northwestern Africa," the authors note, "and correlates with contemporaneous burials across the Strait in southern Iberia."

Such dating helps situate North African burial practices within wider Bronze Age networks. The grave goods and burial style echo Early Bronze Age Iberia, particularly the Argaric and Ferradeira traditions, suggesting either sustained contact or shared cultural logics across the water.

From Pit Graves to Tumuli: A Diversity of Deathscapes

The study documents multiple funerary practices, often coexisting within the same regional landscapes. Early pit graves, flexed burials, and cists represent different modes of bodily treatment. Later periods introduce tumuli and even hypogea—rock-cut subterranean tombs—with grave goods that include copper awls, ostrich eggshells, and gold ornaments.

The diversity of mortuary architecture suggests a complex social fabric. Rather than a top-down system of elite interments, the data imply small-scale, kin-based societies with shared symbolic vocabularies. At Mzoura, a massive circle of standing stones encircles a tumulus. Despite centuries of looting and amateur excavation, enough remains to suggest it once functioned as a long-used ceremonial center.

"The presence of standing stones, rock art, and monumental tombs at transportation crossroads points to their role as territorial and symbolic markers."

Rock Art, Figurines, and Forgotten Cultures

While cemeteries offer skeletal evidence of the dead, the living left other clues. Painted shelters, carved cup-marks, and clay figurines litter the caves of the Tangier Plateau. One particularly intriguing site—"Idol's Cave"—held hundreds of low-fired figurines, some with solar or fertility motifs.

Stylistic comparisons suggest that these forms had ties to both Saharan and Iberian rock art traditions. At Magara Sanar, anthropomorphs painted in red and yellow connect to broader visual traditions across North Africa and into southern Iberia. Such shared symbology underscores the peninsula's long-standing place within Mediterranean and trans-Saharan exchange networks.

Colonial Bias and Archaeological Erasure

That it took until 2025 to publish the first radiocarbon date for a cist grave in northwest Africa is not an accident. As Benattia and colleagues argue, colonial-era archaeology privileged Roman ruins and pharaonic temples while treating North Africa's prehistoric record as either derivative or irrelevant.

Looting, neglect, and uneven funding have left entire swaths of the Moroccan archaeological record undocumented. What does survive is often mislabeled or decontextualized, residing in archives and underfoot in expanding cities. The authors call for more targeted excavation, particularly of the cemeteries near the now-urbanized Tahadart region.

"The Tangier Peninsula's burial traditions offer a regional alternative to cremation-dominated funerary customs in the contemporary Iberian Iron Age."

Interpreting the Ritual Landscape

What emerges from this study is not a simple timeline, but a palimpsest. Cist cemeteries give way to tumuli, which in turn neighbor standing stones and painted caves. Routes wind through them all, suggesting a lived landscape where ritual, memory, and mobility intertwined.

Some burial sites may have served as cenotaphs—symbolic tombs with no human remains. Others likely had seasonal or pilgrimage functions. While genetic and isotopic data remain limited, preliminary results suggest mostly terrestrial diets with minor marine input and likely local ancestry.

More importantly, these findings challenge us to rethink what constitutes the "core" of prehistoric Mediterranean life. The evidence here is not peripheral; it is foundational.

Final Thoughts

The Tangier Peninsula is no longer a forgotten periphery. Through careful excavation and contextualization, its ritual landscape emerges as a central node in prehistoric Africa and its links to the wider Mediterranean. The dead do speak—when we finally begin to listen.

Related Research

* Benattia, H., Onrubia-Pintado, J., & Bokbot, Y. (2025). Cemeteries, rock art and other ritual monuments of the Tangier Peninsula, northwestern Africa, in wider trans-regional perspective (c. 3000–500 BC). African Archaeological Review. https://doi.org/10.1007/s10437-025-09621-z

* Lillios, K. T. (2015). The Archaeology of the Iberian Peninsula: From the Paleolithic to the Bronze Age. Cambridge University Press.

* Broodbank, C., & Lucarini, G. (2019). The dynamics of Mediterranean Africa 10,000–1000 BC. In The Cambridge World History, Vol. 2.

* González-Toraya, I., et al. (2010). Population dynamics and ancestry in prehistoric southern Iberia: A case study from Loma del Puerco. Journal of Human Evolution. https://doi.org/10.1016/j.jhevol.2010.03.005

* Daugas, J. P., et al. (2006). Le Cromlech de Mzoura. Bulletin d’Archéologie Marocaine.

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

In the story of human evolution, our hands often play a supporting role—literally and metaphorically. Yet what if the fingers of ancient hominins could tell us more than just when our ancestors picked up a stone tool? What if the bone beneath the surface preserved traces of not just what our relatives could do—but how they actually did it?

A new study led by Samar Syeda and colleagues, published in Science Advances digs deep—into the finger bones of two fossil hominins from South Africa—and finds that Australopithecus sediba and Homo naledi used their hands in markedly different ways. This difference, preserved in the thickness and shape of their phalangeal cortical bone, hints at evolutionary "experiments" in how to balance climbing and manipulation long before the emergence of Homo sapiens.

Internal Histories Written in Bone

To understand how ancient hominins used their hands, Syeda’s team turned to a part of the body often overlooked in paleoanthropology: the internal structure of finger bones. Specifically, they analyzed the cortical bone—dense, load-bearing tissue that thickens or thins in response to how fingers are used in life. A lifetime of grasping, manipulating, or climbing leaves an imprint in the form of bone thickness and stress patterns, particularly in the phalanges.

The study focused on two remarkable fossils: the nearly complete hand of Australopithecus sediba (MH2), dated to about 2 million years ago from Malapa, and the equally well-preserved hand of Homo naledi, dated to about 250,000 years ago from the Rising Star cave system. While previous analyses highlighted similarities in hand proportions to modern humans, this study reveals critical differences below the surface.

"The phalangeal cortical structure demonstrates diversity in Plio-Pleistocene hand use, with A. sediba and H. naledi each indicating different dexterous abilities and different climbing strategies," the authors write.

Australopithecus sediba: A Climber with a Curious Thumb

At first glance, A. sediba's hands seem to reflect a blend of human and ape features. The thumb is long and relatively human-like, and yet the overall curvature of the fingers and their internal bone structure resemble those of modern apes—especially orangutans.

Syeda and colleagues found that cortical bone in A. sediba's fingers was thickest along the palmar (grasping) side, especially near the flexor sheath ridges. This pattern closely mirrors that of tree-climbing primates and implies the fingers bore heavy loads from locomotion—particularly climbing.

But not all digits told the same story. The thumb and little finger showed patterns more consistent with human-like manipulation. Combined with the hand’s external anatomy—such as its long thumb—this suggests that A. sediba retained a capacity for grasping and manipulating objects, perhaps including early tools, while still regularly climbing.

"These two digits are more likely to reflect potential signals of manipulation because they are less often used or experience less load during climbing or suspensory locomotion," the authors note.

The fifth digit (the pinky) in particular may have played a role in tool use, a hypothesis strengthened by its internal thickening and external shape—though A. sediba has not yet been directly associated with stone tools.

Homo naledi: A Rock Climber in the Shadows?

If A. sediba walked the line between tree and tool, H. naledi seems to have invented its own playbook.

Despite living hundreds of thousands of years after A. sediba, and contemporaneously with early Homo sapiens, H. naledi retained ape-like features—especially in the curvature of its intermediate finger bones. But inside those bones lay a surprise.

Unlike any modern primate or fossil hominin yet studied, H. naledi showed a hybrid cortical pattern. The proximal finger bones had thick dorsal cortices, like those of modern humans, suggesting loads consistent with manipulation or forceful precision grips. Meanwhile, the intermediate phalanges retained thick palmar cortices and pronounced curvature, indicating continued use in climbing or heavy grasping.

"This distinct pattern was unexpected and indicates that H. naledi likely used and loaded different regions of its fingers in different ways," writes Syeda.

One hypothesis? Crimp grips. Common in modern rock climbers, this grip involves strong loading of the fingertips and requires precise coordination of flexor muscles and tendons. In H. naledi, the cortical thickness patterns resemble what’s seen in these climbing adaptations, though more research is needed to confirm whether vertical rock faces were part of this species’ daily routine.

The Nonlinear Evolution of Human Hands

The fossil hands of A. sediba and H. naledi offer a corrective to oversimplified narratives of human evolution. Rather than a straight path from climbing ape to tool-wielding human, these species exemplify different evolutionary strategies for navigating a world that required both dexterity and mobility.

"This work offers yet more evidence that human evolution is not a single, linear transition from upright walking to increasingly better tool use, but is rather characterized by different 'experiments' that balanced the need to both manipulate and to move," notes Tracy Kivell, senior author on the study.

The key innovation here is methodological. By moving beyond surface anatomy and probing the internal structure of fossil bones, researchers are better able to infer actual behavior, not just potential. These "ecophenotypic" signals—plastic traits shaped by life experience—may bridge the gap between morphology and motion.

A Final Grip

While neither A. sediba nor H. naledi has been found with tools in hand, their bones suggest they could have used them—perhaps not in the same ways, or for the same purposes, but with dexterity nonetheless. The hand, like the brain, is a canvas for behavioral evolution. And sometimes, the most telling features lie just beneath the surface.

Related Research

This study builds upon a growing body of literature focused on hand use, locomotion, and bone plasticity in hominin evolution:

* Bird, E. E., et al. (2024). Trabecular bone structure of the proximal capitate in extant hominids and fossil hominins with implications for midcarpal joint loading and the dart-thrower’s motion. American Journal of Biological Anthropology, 183(2), e24824. DOI: 10.1002/ajpa.24824

* Skinner, M. M., et al. (2015). Human-like hand use in Australopithecus africanus. Science, 347(6220), 395–399. DOI: 10.1126/science.1261735

* Tocheri, M. W., et al. (2008). The evolutionary history of the hominin hand since the last common ancestor of Pan and Homo. Journal of Anatomy, 212(4), 544–562. DOI: 10.1111/j.1469-7580.2008.00865.x

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe

“The archaeological record shows shifts in empires and cultures. But beneath the soil, the genetic signal told a different story—of people staying put, generation after generation.”

A Long Memory in the Zagros

On the northern edges of the Iranian Plateau, where the foothills of the Alborz Mountains give way to fertile valleys and ancient caravan trails, archaeologists and geneticists have uncovered an unexpected thread in the human story. This is not a tale of invasion or conquest, nor of radical demographic upheaval. Instead, it is a portrait of long-term continuity—one that stretches over 3,000 years of human occupation, from the Copper Age through the rule of the Sassanid Empire.

In a new study published in Scientific Reports, researchers analyzed ancient DNA from 50 individuals recovered at nine archaeological sites across northern Iran. These genomes, some dating back to 4700 BCE, reveal a remarkable degree of genetic stability across time. Despite profound cultural shifts, shifting trade networks, and the arrival and fall of empires, the underlying genetic profile of people in this region remained strikingly consistent. The result is one of the most extensive and well-supported cases of diachronic genetic continuity ever documented in the ancient world.

Continuity in a Crossroads

The Iranian Plateau has long been described as a crossroads of civilizations. Nestled between Mesopotamia, Central Asia, the Caucasus, and the Indian subcontinent, this region has seen waves of migration, commerce, and political upheaval for millennia. Yet the latest findings from Amjadi and colleagues complicate this long-held view. While it is true that the region was anything but isolated, the genetic data from its inhabitants suggest that movement and cultural exchange did not necessarily equate to population turnover.

The study focused primarily on northern Iran, particularly the Caspian region—a zone that played host to the Achaemenid, Parthian, and Sassanid empires. These empires were expansive, multiethnic, and deeply embedded in the trade routes of the ancient Silk Roads. And yet, even under these dynamic circumstances, the DNA tells a quieter story: one of people who stayed rooted, generation after generation. These ancient individuals, some buried with goods from distant lands, nonetheless belonged to a lineage that had persisted locally for thousands of years.

A Genetic Tether Through Time

The researchers sequenced 23 mitochondrial genomes and 13 nuclear genomes from remains spanning more than three millennia. From sites such as Gol Afshan Tepe, Liarsangbon, and Vestemin, the sampled individuals ranged in time from the early Chalcolithic to the early second millennium CE. What emerged from their genetic profiles was a consistent ancestral signature tracing back to the early Neolithic farmers of Ganj Dareh—a well-known archaeological site in the central Zagros.

Maternal lineages were dominated by West Eurasian haplogroups such as H, J, U, T, and HV, which continue to appear in modern Iranian populations today. Paternal lineages also showed deep roots, with J1 and J2 haplogroups—often linked to Near Eastern Neolithic expansions—maintaining a strong presence across the centuries. In supervised ADMIXTURE analyses and principal component plots, the majority of the newly sampled individuals clustered closely with Neolithic Iranian genomes. This alignment held steady from the Chalcolithic through the Sassanid period.

The study also uncovered subtle evidence of diversity: minor contributions from South-Central Asia, Anatolia, and the Levant, particularly during the Bronze Age. However, these contributions were not large enough to disrupt the underlying genetic continuity. They appear more as traces of interaction—markers of trade or intermittent movement—than signs of large-scale population replacement.

When Culture Changes, But People Stay

This genetic continuity finds an echo in the archaeological record. For instance, catacomb-style burial traditions, first seen around 3000 BCE in southeastern Iran, appear again in Parthian contexts more than two thousand years later. This suggests a cultural persistence across time and space, likely reinforced by long-term regional occupation. Similarly, artificial cranial deformation—a deliberate reshaping of skulls seen as a cultural marker—was found in individuals from Gol Afshan Tepe, linking them with earlier Neolithic sites in the Zagros, such as Ali Kosh.

In many other regions of Eurasia, the rise of new technologies or elites has been tied to demographic change—pastoralist expansions from the Pontic Steppe, for example, reshaped the genetic landscape of Bronze Age Europe. But in the case of the Iranian Plateau, empire did not equate to erasure. The Achaemenids, Seleucids, Parthians, and Sassanids introduced new governance, material cultures, and systems of trade. Yet they governed a people who remained, in large part, genetically consistent with their distant ancestors.

Methods That Look Beyond Bones

To piece together this long arc of continuity, the team combined cutting-edge ancient DNA techniques with robust comparative datasets. Sequencing strategies included shotgun sequencing and hybridization capture using the 1240k SNP panel. Comparative analysis drew from the Allen Ancient DNA Resource and modern reference genomes, alongside statistics like qpAdm and f4 tests to estimate admixture proportions.

The researchers also examined runs of homozygosity to evaluate population structure and inbreeding. Most individuals exhibited low ROH signals, suggesting relatively large and outbred local populations. Even as cultural centers like Shahr-i Sokhta rose and fell, the genetic makeup of surrounding communities showed remarkable resilience.

Why Continuity Matters

This study doesn’t just contribute another ancient genome to the global dataset. It shifts how we interpret cultural transformation in archaeology. The assumption that major shifts in material culture, urbanization, or empire correspond to new populations is often implicit in archaeological narratives. But here, the evidence points in a different direction. People may adopt new languages, practices, and technologies while remaining, genetically, descendants of long-standing local populations.

The Iranian Plateau, particularly in its northern reaches, thus becomes a test case for cultural resilience. Rather than viewing human history as a succession of replacements, the findings from this study invite us to see it as a process of adaptation and continuity. The Silk Road didn’t erase these communities. Empires didn’t overwrite them. Instead, they absorbed and were shaped by them.

Related Research and Further Reading

* Lazaridis, I. et al. (2016). Genomic insights into the origin of farming in the ancient Near East. Nature, 536, 419–424. https://doi.org/10.1038/nature19310

* Narasimhan, V. M. et al. (2019). The formation of human populations in South and Central Asia. Science, 365(6457). https://doi.org/10.1126/science.aat7487

* Jeong, C. et al. (2019). The genetic history of admixture across Inner Eurasia. Nature Ecology & Evolution, 3, 966–976. https://doi.org/10.1038/s41559-019-0878-2

* Allentoft, M. E. et al. (2024). Population genomics of post-glacial Western Eurasia. Nature, 625, 301–311. https://doi.org/10.1038/s41586-024-07040-2

* Amjadi, M. A. et al. (2025). Ancient DNA indicates 3,000 years of genetic continuity in the Northern Iranian Plateau. Scientific Reports, 15, 16530. https://doi.org/10.1038/s41598-025-99743-w

This is a public episode. If you'd like to discuss this with other subscribers or get access to bonus episodes, visit www.anthropology.net/subscribe