Rise of archery in Andes Mountains dated to 5,000 years ago — earlier than previous research

When did archery arise in the Americas? And what were the effects of this technology on society?

These questions have long been debated among anthropologists and archaeologists. But a study led by a University of California, Davis, anthropologist, is shining light on this mystery.

Focusing on the Lake Titicaca Basin in the Andes mountains, anthropologists found through analysis of 1,179 projectile points that the rise of archery technology dates to around 5,000 years ago. Previous research held that archery in the Andes emerged around 3,000 years ago.

The new research indicates that the adoption of bow-and-arrow technology coincided with both the expansion of exchange networks and the growing tendency for people to reside in villages.

“We think our paper is groundbreaking because it gives us a chance to see how society changed throughout the Andes throughout ancient times by presenting a huge number of artifacts from a vast area of South America,” said Luis Flores-Blanco, an anthropology doctoral student and corresponding author of the paper. “This is among the first instances in which Andean archaeologists have investigated social complexity through the quantitative analysis of stone tools.”

The study was published online in November in Quaternary International.

Researchers said increasing social complexity in the region is usually investigated through analysis of monumental architecture and ceramics rather than projectile points, which are historically linked to foraging communities.

Pooling from 10,000 years of history

For the study, the team examined more than a thousand projectile points created over 10,000 years. Each projectile point originated in the Lake Titicaca Basin, specifically the Ilave and Ramis valleys, which are located southwest and northwest of the basin, respectively.

Flores-Blanco said it’s among the highest plateau lands explored and conquered by humans, with Lake Titicaca sitting at an elevation of 12,500 feet.

“At Titicaca, Andeans accomplished the remarkable achievement of domesticating plants like the potato, leaving behind a nutritious legacy that is still appreciated today,” he said. “On top of that, the Tiwanaku were one of the major Andean civilizations that built their vast territory here. Even the Inca Empire claimed this territory was their mythical place of origin. Our study digs even deeper and goes to the roots of this Andean civilization.”

In their analysis, Flores-Blanco and his colleagues considered each projectile’s date of origin and then measured its length, width, thickness and weight. They noticed that older projectile points — from the Early Archaic through the Late Archaic — were larger. A significant decrease in size occurred during the Terminal Archaic period, around 5,000 years ago. The team hypothesized that this size shift indicates a change in preference from spear-throwing technology to bow-and-arrow technology, but without abandoning the old technologies.  

In addition, the team compared their projectile data to archaeological data from the region concerning settlement sizes, raw material availability and cranial trauma data. During the Terminal Archaic period, settlement sizes increased but the total number of settlement sites decreased, researchers said. Not only that, but the inhabitants lacked signs of social violence, even though they had access to exotic raw materials.

“Based on our discovery, we can suggest that bow-and-arrow technology could have maintained and ensured adherence to emerging social norms that were crucial, such as those observed in the development of new social institutions, like obsidian exchange hubs or among individuals establishing residence in expanding villages,” Flores-Blanco said. 

Flores-Blanco co-authored the study with Lucero Cuellar, National University of San Marcos; Mark Aldenderfer, UC Merced; Charles Stanish, University of South Florida; and Randall Haas, University of Wyoming and formerly of UC Davis.  

War and fire on the eastern Silk Road

 

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TYPICAL SCENES OF FIRES TRIGGERED BY WARFARE ACTIVITY IN ANCIENT CHINA. (PROVIDED BY AUTHORS)

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CREDIT: ZHANG ET AL

Human activities such as intentional burning, agriculture, pastoralism, and metallurgy can affect the frequency of fire in an ecosystem. Guanghui Dong, Aifeng Zhou and colleagues investigated whether another typical human activity has influenced fire history in the areas along the Silk Road: war. Fire was a commonly used weapon in ancient Chinese warfare. In the 5th-century BCE, military strategist Sun Tzu, author of The Art of War, advised the use of fire against enemy troops and supplies. The authors measured black carbon, soot, and char in sediments from a core of Tianchi Lake, which represent 6,000 years of sediment deposition. The authors calculated the spatial range of land that would have contributed fire-related particulate to the sediment using the potential source contribution function analysis, a method typically used to determine the source areas for contemporary pollution. Fire was infrequent in the middle Holocene, but became more frequent in the late Holocene, as the climate became drier and flammable herbaceous vegetation spread. Then, 2,000 years ago, the fire frequency became decoupled from climate or vegetation. On centennial timescales, fires during this period are synchronous with warfare, as recorded in the List of Wars in Historical China. From 2,000–400 years ago, warfare between different political powers may have been the dominant contributor to high-intensity fires in the area, according to the authors.

Ancient Sahul's submerged landscapes reveal a mosaic of human habitation

 

 

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DURING LOWER SEA LEVELS A VAST ARCHIPELAGO FORMED ON THE AUSTRALIAN NORTHWEST CONTINENTAL SHELF (TOP). A MODERN-DAY EXAMPLE OF AN ARCHIPELAGO ON A SUBMERGED CONTINENTAL SHELF IS THE ÅLAND ISLANDS NEAR FINLAND (BOTTOM).

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CREDIT: US GEOLOGICAL SURVEY, GEOSCIENCE AUSTRALIA

New research conducted by a team of archaeologists and earth scientists has shed light on the ancient landscapes of Sahul, the Pleistocene (Ice Age) landmass comprising Australia and New Guinea.  

The findings, published this week in Quaternary Science Reviews, offer a fascinating glimpse into a previously unrecognised chapter of human history. 

For the majority of the last 65,000 years of human history in Australia, lower sea levels revealed a vast expanse of dry land in the northwest of the continent, connecting the Kimberley and Arnhem Land into a contiguous area.  

Through meticulous analysis of high-resolution bathymetric data (ocean floor topography), it has been unveiled that this region, now submerged, existed as an extensive archipelago during Marine Isotope Stage 4 (71,000-59,000 years ago), which remained stable for ~9000 years  

This transformed into a fully exposed shelf in Marine Isotope Stage 2 (29,000–14,000 years ago), featuring an inland sea adjacent to a sizable freshwater lake, encircled by high escarpments cut by deep gorges.  

The team's demographic modelling indicates that this now-submerged shelf experienced fluctuating potential carrying capacities through Marine Isotope Stages 4–2, potentially supporting populations ranging from 50,000 to 500,000 people at various times.  

However, rapid global sea level rises between 14,500 – 14,100 years ago (during Meltwater Pulse 1A) and between 12,000 and 9,000 years ago resulted in the rapid inundation of approximately 50% of the Northwest Shelf, causing profound changes in the space of human life spans. 

These events likely triggered the retreat of human populations ahead of the encroaching coastline, evident in peaks of occupational intensity at archaeological sites across the Kimberley and Arnhem, and the sudden appearance of distinctive new rock art styles in both regions. 

Lead researcher Kasih Norman said: “The presence of this extensive archipelago likely facilitated the successful dispersal of the first maritime explorers from Wallacea – the region of modern-day Indonesia - providing a familiar environment for their adaptation to the vast continent of Sahul.” 

Furthermore, the study emphasised the critical role that the now-submerged continental margins played in early human expansions.  

“The temptation to overlook the continental shelf margins of Late Pleistocene Sahul in discussions of early peopling and expansion risks oversimplification and misunderstanding of this pivotal period in history," added Norman. 

The implications of these findings underscored the need to reevaluate the narrative of early human migration and the impact of climate change on ancient populations.  

Norman said: “Our demographic modelling showed a peak in population size at the height of the last ice age ~20,000 years ago, when the entire extent of the Northwest Shelf was dry land. This finding has now been supported by new genetic research showing very large populations for the Tiwi Islanders – located just to the east of the study region – at the height of the last glacial period.”  

As submerged landscapes continued to yield invaluable archaeological insights, the rise of undersea archaeology in Australia contributed to a global understanding of human migration during the Late Pleistocene. 

This research marked a significant milestone in understanding the complex interplay between ancient landscapes, human populations and environmental change. Dr Norman said as exploration and analysis of underwater sites expanded, it promised to unravel more secrets of our shared human history. 

The study ‘Sea level rise drowned a vast habitable area of north-western Australia driving long-term cultural change’ has been published in Quaternary Science Reviews. 

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JOURNAL

Ancient Balkan genomes reveal how Slavic Europe was formed

 

146 individuals who inhabited the Balkan Peninsula during the first millennium have been analysed

 

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SKULL OF A SOUTH-SAHARAN AFRICAN INDIVIDUAL FOUND AT VIMINACIUM WITH THE LEGIONARY LAMP HE HAD IN HIS GRAVE.

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CREDIT: MIODRAG (MIKE) GRBIC

Iñigo Olalde, Ikerbasque Research Fellow at the UPV/EHU and Ramón y Cajal Researcher has, together with the Institute of Evolutionary Biology (IBE: CSIC-UPF) and Harvard University, led a study in which they have, for the first time, reconstructed the genomic history of the first millennium of the Balkan Peninsula. To do so, the team recovered and analysed the ancient genome of 146 individuals who inhabited present-day Croatia and Serbia during that period. The work, published in the prestigious journal Cell, depicts the Balkans as a global, cosmopolitan frontier of the Roman Empire and reconstructs the arrival of Slavic peoples in this region. 

For the first time, the team has identified three individuals of African origin who lived in the Balkans under Rome's imperial rule. Furthermore, the research establishes that the migration of Slavic peoples from the 6th century onwards represented one of the biggest permanent demographic changes in the whole of Europe, the cultural influence of which continues to this day. 

The Roman Empire transformed the Balkans into a global region  

First the Roman Republic and then the Roman Empire incorporated the Balkans and turned this border region into a crossroads of communications and a melting pot of cultures. This is confirmed by the study which reveals that immigrants from far away were attracted to the region by the economic vitality of the empire. 

Through the analysis of ancient DNA, the team was able to identify that, during Roman rule in the region, there was a large demographic influx from the Anatolian Peninsula (located in modern-day Turkey) that left a genetic imprint on the Balkan populations. Yet no trace of Italic ancestry has been observed in the genomes analysed. “These populations that had come from the East were fully integrated into the local Balkan society. At Viminacium, for example (one of the main cities of the Romans, located in present-day Serbia), we found an exceptionally rich sarcophagus in which a man of local descent and a woman of Anatolian descent had been buried,” said the lead author of the article Íñigo Olalde, Ikerbasque Research Fellow in the BIOMICs group at the UPV/EHU and research associate at Harvard University (he had previously been a "La Caixa Junior Leader" researcher in the IBE's Palaeogenomics group). 

The team also revealed the sporadic long-distance mobility of three individuals of African descent to the Balkan Peninsula while under imperial rule. One of them was a teenager, whose genetic origins are to be found in the region of present-day Sudan, beyond the boundaries of the ancient Empire. “The isotopic analysis of the roots of his teeth revealed that in his childhood he had a seafood diet very different from that of the rest of the individuals analysed,” said Carles Lalueza-Fox, senior researcher at the Institute of Evolutionary Biology (IBE) and director of the Museum of Natural Sciences of Barcelona (MCNB). 

What is more, he had been buried with an oil lamp representing an iconography of the eagle, which is related to Jupiter, one of the most important gods for the Romans. Lalueza-Fox pointed out that “archaeological analysis of his grave reveals that he may have been part of the Roman military forces, so we would be talking about an immigrant who had travelled from a long way away to the Balkans in the 2nd century CE”. “This indicates to us a diverse, cosmopolitan Roman Empire, which embraced populations from far beyond the European continent.”  

The Roman Empire welcomed barbarian populations long before its fall 

The study identified a number of individuals of northern European and steppe ancestry who inhabited the Balkan Peninsula during the 3rd century at the height of the Roman occupation. Anthropological analysis of their skulls reveals that some of them were artificially deformed, a custom peculiar to certain populations of the steppes and the Huns, often referred to as “barbarians”. 

These findings support historical and archaeological research and point to the presence of individuals from outside the borders of the Empire, beyond the Danube, long before the fall of the Western Empire. “The borders of the Empire were much more diffuse than the borders of today's nation states. The Danube served as a geographical boundary of the Empire but acted as a communication route and was highly permeable to the movement of people,” said Pablo Carrión, IBE researcher and co-lead author of the study. 

Slavic populations altered the demographics of the Balkan region 

Following the fall of the Western Roman Empire, and in particular from the 6th century onwards, the study reveals the large-scale arrival in the Balkans of individuals genetically similar to the modern Slavic-speaking populations of Eastern Europe. Their genetic footprint represents between 30% and 60% of the ancestry of today's Balkan peoples, which constitutes one of the largest permanent demographic shifts anywhere in Europe during the period of the Great Migrations. 

Although the study detects the sporadic arrival of individuals from Eastern Europe during earlier periods, it is from the 6th century onwards that a strong migratory surge can be observed. “According to our ancient DNA analysis, this arrival of Slavic-speaking populations in the Balkans took place across several generations and involved entire family groups including both men and women,” explained Carrión. 

The study also identifies that the establishment of Slavic populations in the Balkans was bigger in the north, with a genetic contribution of 50-60% in present-day Serbia, and gradually smaller towards the south, with a genetic representation of 30-40% in mainland Greece and up to 20% in the Aegean islands. “Their genetic legacy is visible not only in today's Balkan Slavic-speaking populations, but also in other groups that include regions where Slavic languages are not currently spoken, such as Romania and Greece,” said David Reich, a researcher at Harvard University in whose lab the recovery and sequencing of the ancient DNA was carried out. 

Coordination and cooperation to rewrite Balkan history 

The 1991 war in Yugoslavia led to the separation of the Balkan peoples into the various countries that currently make up the region, and its consequences persist to this day. However, researchers from across the region have collaborated on the study. “Croatian and Serbian researchers have been collaborating on the study. This is a great example of cooperation, given the recent history of the Balkan Peninsula. At the same time, this type of work is an example of how objective genomic data can contribute towards leaving behind social and political problems linked to collective identities that have been based on epic narratives of the past,” said Lalueza-Fox. 

The team developed a de novo genetic database of the Serbian population in order to reconstruct the history of the Balkans. “We were faced with the situation in which there was no genomic database of the current Serbian population. In order to construct it and use it as a comparative reference in this study, we had to look for people who called themselves Serbs on the basis of certain shared cultural traits, even if they lived in other countries such as Montenegro or North Macedonia,” said Miodrag Grbic, lecturer at the University of Western Ontario and visiting lecturer at the University of La Rioja. 

Despite the question of identity, marked by the more recent history of the Balkans, the genomes of the Croatians and Serbians analysed speak of a heritage shared in equal measure between Slavic and Mediterranean populations. 

As Lalueza-Fox pointed out, “we believe that, together with archaeological data and historical records, the analysis of ancient DNA can contribute towards the reconstruction of the history of the Balkan peoples and the formation of the so-called Slavic peoples of southern Europe.” 

“The image that emerges is not one of division, but of a shared history. The Iron Age people inhabiting the Balkan region were similarly affected by migrations during the time of the Roman Empire and by Slavic migrations later on. Together, these influences gave rise to the genetic profile of the modern Balkans, regardless of national borders,” concluded Grbic.  

Mesopotamian bricks unveil the strength of Earth’s ancient magnetic field

Ancient bricks inscribed with the names of Mesopotamian kings have yielded important insights into a mysterious anomaly in Earth’s magnetic field 3,000 years ago, according to a new study involving UCL researchers

Peer-Reviewed Publication

UNIVERSITY COLLEGE LONDON

 

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BRICK DATES TO THE REIGN OF NEBUCHADNEZZAR II (CA. 604 TO 562 BCE) BASED ON THE INTERPRETATION OF THE INSCRIPTION. THIS OBJECT WAS LOOTED FROM ITS ORIGINAL CONTEXT BEFORE BEING ACQUIRED BY THE SLEMANI MUSEUM AND STORED IN THAT MUSEUM WITH AGREEMENT FROM THE CENTRAL GOVERNMENT. IMAGE COURTESY OF THE SLEMANI MUSEUM

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CREDIT: SLEMANI MUSEUM

Ancient bricks inscribed with the names of Mesopotamian kings have yielded important insights into a mysterious anomaly in Earth’s magnetic field 3,000 years ago, according to a new study involving UCL researchers.

The research, published in the Proceedings of the National Academy of Sciences (PNAS), describes how changes in the Earth’s magnetic field imprinted on iron oxide grains within ancient clay bricks, and how scientists were able to reconstruct these changes from the names of the kings inscribed on the bricks.

The team hopes that using this “archaeomagnetism,” which looks for signatures of the Earth's magnetic field in archaeological items, will improve the history of Earth’s magnetic field, and can help better date artefacts that they previously couldn’t.

Co-author Professor Mark Altaweel (UCL Institute of Archaeology) said: “We often depend on dating methods such as radiocarbon dates to get a sense of chronology in ancient Mesopotamia. However, some of the most common cultural remains, such as bricks and ceramics, cannot typically be easily dated because they don’t contain organic material. This work now helps create an important dating baseline that allows others to benefit from absolute dating using archaeomagnetism.”

The Earth’s magnetic field weakens and strengthens over time, changes which imprint a distinct signature on hot minerals that are sensitive to the magnetic field. The team analysed the latent magnetic signature in grains of iron oxide minerals embedded in 32 clay bricks originating from archaeological sites throughout Mesopotamia, which now overlaps with modern day Iraq. The strength of the planet’s magnetic field was imprinted upon the minerals when they were first fired by the brickmakers thousands of years ago.

At the time they were made, each brick was inscribed with the name of the reigning king which archaeologists have dated to a range of likely timespans. Together, the imprinted name and the measured magnetic strength of the iron oxide grains offered a historical map of the changes to the strength of the Earth’s magnetic field.

The researchers were able to confirm the existence of the “Levantine Iron Age geomagnetic Anomaly,” a period when Earth’s magnetic field was unusually strong around modern Iraq between about 1050 to 550 BCE for unclear reasons. Evidence of the anomaly has been detected as far away as China, Bulgaria and the Azores, but data from within the southern part of the Middle East itself had been sparse.

Lead author Professor Matthew Howland of Wichita State University said: “By comparing ancient artefacts to what we know about ancient conditions of the magnetic field, we can estimate the dates of any artifacts that were heated up in ancient times.”

To measure the iron oxide grains, the team carefully chipped tiny fragments from broken faces of the bricks and used a magnetometer to precisely measure the fragments.

By mapping out the changes in Earth’s magnetic field over time, this data also offers archaeologists a new tool to help date some ancient artefacts. The magnetic strength of iron oxide grains embedded within fired items can be measured and then matched up to the known strengths of Earth’s historic magnetic field. The reigns of kings lasted from years to decades, which offers better resolution than radiocarbon dating which only pinpoints an artefact’s date to within a few hundred years.

An additional benefit of the archaeomagnetic dating of the artefacts is it can help historians more precisely pinpoint the reigns of some of the ancient kings that have been somewhat ambiguous. Though the length and order of their reigns is well known, there has been disagreement within the archaeological community about the precise years they took the throne resulting from incomplete historical records. The researchers found that their technique lined up with an understanding of the kings' reigns known to archaeologists as the "Low Chronology".

The team also found that in five of their samples, taken during the reign of Nebuchadnezzar II from 604 to 562 BCE, the Earth’s magnetic field seemed to change dramatically over a relatively short period of time, adding evidence to the hypothesis that rapid spikes in intensity are possible.

Co-author Professor Lisa Tauxe of the Scripps Institution of Oceanography (US) said: “The geomagnetic field is one of the most enigmatic phenomena in earth sciences. The well-dated archaeological remains of the rich Mesopotamian cultures, especially bricks inscribed with names of specific kings, provide an unprecedented opportunity to study changes in the field strength in high time resolution, tracking changes that occurred over several decades or even less.”

The research was carried out with funding from the U.S.-Israel Binational Science Foundation.

North America’s first people may have arrived by sea ice highway

 

New research suggests some early Americans may have travelled on winter sea ice down the coast from Beringia as long as 24,000 years ago

 One of the hottest debates in archeology is how and when humans first arrived in North America. Archaeologists have traditionally argued that people walked through an ice-free corridor that briefly opened between ice sheets an estimated 13,000 years ago.  

But a growing number of archeological and genetic finds — including human footprints in New Mexico dated to around 23,000 years old — suggests that people made their way onto the continent much earlier. These early Americans likely traveled along the Pacific coastline from Beringia, the land bridge between Asia and North America that emerged during the last glacial maximum when ice sheets bound up large amounts of water causing sea levels to fall.  

Now, in research to be presented Friday, 15 December at the American Geophysical Union Annual Meeting (AGU23) in San Franciso, paleoclimate reconstructions of the Pacific Northwest hint that sea ice may have been one way for people to move farther south.  

The idea that early Americans may have traveled along the Pacific Coast isn’t new. People were likely south of the massive ice sheets that once covered much of the continent by at least 16,000 years ago. Given that the ice-free corridor wouldn’t be open for thousands of years before these early arrivals, scientists instead proposed that people may have moved along a “kelp highway.” This theory holds that early Americans slowly traveled down into North America in boats, following the bountiful goods found in coastal waters.  

Archeologists have found evidence of coastal settlements in western Canada dating from as early as 14,000 years ago. But in 2020, researchers noted that freshwater from melting glaciers at the time may have created a strong current that would make it difficult for people to travel along the coast. 

Ice highway over dangerous water 

To get a fuller picture of ocean conditions during these crucial windows of human migration, Summer Praetorius of the US Geological Survey and her colleagues looked at climate proxies in ocean sediment from the coast. Most of the data came from tiny, fossilized plankton. The abundance and chemistry of these organisms help reconstruct ocean temperatures, salinity and sea ice cover.  

Praetorious’ presentation is part of a session on the climate history and geology of Beringia and the North Pacific during the Pleistocene, the current ice age, at AGU23. The week-long conference has brought 24,000 experts from across the spectrum of the Earth and space sciences to San Francisco this year and connected 3,000 online attendees.  

Praetorious’ team used climate models and found that ocean currents were more than twice the strength they are today during the height of the last glacial maximum around 20,000 years ago due to glacial winds and lower sea levels. While not impossible, to paddle against, these conditions would have made traveling by boat very difficult, Praetorius said. 

However, the records also showed that much of the area was home to winter sea ice until around 15,000 years ago. As a cold-adapted people, “rather than having to paddle against this horrible glacial current, maybe they were using the sea ice as a platform,” Praetorius said.  

Arctic people today travel along sea ice on dog sleds and snow mobiles. Early Americans may also have used the ‘sea ice highway’ to get around and hunt marine mammals, slowly making their way into North America in the process, Praetorius said. The climate data suggest conditions along the coastal route may have been conducive to migration between 24,500-22,000 years ago and 16,400-14,800 years ago, possibly aided by the presence of winter sea ice.  

While proving that people were using sea ice to travel will be tricky given most of the archeological sites are underwater, the theory provides a new framework for understanding how humans may have arrived in North America without a land bridge or easy ocean travel.  

And the sea ice highway isn’t mutually exclusive with other human migrations further down the line, says Praetorius. The team’s models show , the Alaskan current had calmed down by 14,000 years ago, making it easier for people to travel by boat along the coast.  

“Nothing is off the table,” she said. "We will always be surprised by ancient human ingenuity." 

Were Neanderthals morning people ?

 

A new paper in Genome Biology and Evolution, published by Oxford University Press, finds that genetic material from Neanderthal ancestors may have contributed to the propensity of some people today to be “early risers,” the sort of people who are more comfortable getting up and going to bed earlier.

All anatomically modern humans trace their origin to Africa around 300 thousand years ago, where environmental factors shaped many of their biological features. Approximately seventy-thousand years ago, the ancestors of modern Eurasian humans began to migrate out to Eurasia, where they encountered diverse new environments, including higher latitudes with greater seasonal variation in daylight and temperature.

But other hominins, such as the Neanderthals and Denisovans, had lived in Eurasia for more than 400,000 years. These archaic hominins diverged from modern humans around 700,000 ago, and as a result, our ancestors and archaic hominins evolved under different environmental conditions. This resulted in the accumulation of lineage-specific genetic variation and phenotypes. When humans came to Eurasia, they interbred with the archaic hominins on the continent, and this created the potential for humans to gain genetic variants already adapted to these new environments.

Previous work has demonstrated that much of the archaic hominin ancestry in modern humans was not beneficial and removed by natural selection, but some of the archaic hominin variants remaining in human populations show evidence of adaptation. For example, archaic genetic variants have been associated with differences in hemoglobin levels at higher altitude in Tibetans, immune resistance to new pathogens, levels of skin pigmentation, and fat composition.

Changes in the pattern and level of light exposure have biological and behavioral consequences that can lead to evolutionary adaptations. Scientists have previously explored the evolution of circadian adaptation in insects, plants, and fishes extensively, but it is not well studied in humans. The Eurasian environments where Neanderthals and Denisovans lived for several hundred thousand years are located at higher latitudes with more variable daylight times than the landscape where modern humans evolved before leaving Africa. Thus, the researchers explored whether there was genetic evidence for differences in the circadian clocks of Neanderthals and modern humans.

The researchers defined a set of 246 circadian genes through a combination of literature search and expert knowledge. They found hundreds of genetic variants specific to each lineage with the potential to influence genes involved in the circadian clock. Using artificial intelligence methods, they highlighted 28 circadian genes containing variants with potential to alter splicing in archaic humans and 16 circadian genes likely divergently regulated between present-day humans and archaic hominins. This indicated that there were likely functional differences between in the circadian clocks in archaic hominins and modern humans. Since the ancestors of Eurasian modern humans and Neanderthals interbred, it was thus possible that some humans could have obtained circadian variants from Neanderthals.

To test this, the researchers explored whether introgressed genetic variants—variants that moved from Neanderthals into modern humans—have associations with the preferences of the body for wakefulness and sleep in large cohort of several hundred thousand people from the UK Biobank. They found many introgressed variants with effects on sleep preference, and most strikingly, they found that these variants consistently increase morningness, the propensity to wake up early. This suggests a directional effect on the trait and is consistent with adaptations to high latitude observed in other animals.

Increased morningness in humans is associated with a shortened period of the circadian clock. This is likely beneficial at higher latitudes, because it has been shown to enable faster alignment of sleep/wake with external timing cues. Shortened circadian periods are required for synchronization to the extended summer light periods of high latitudes in fruit flies, and selection for shorter circadian periods has resulted in latitudinal clines of decreasing period with increasing latitude in natural fruit fly populations. Therefore, the bias toward morningness in introgressed variants may indicate selection toward shortened circadian period in the populations living at high latitudes. The propensity to be a morning person could have been evolutionarily beneficial for our ancestors living in higher latitudes in Europe and thus would have been a Neanderthal genetic characteristic worth preserving.

“By combining ancient DNA, large-scale genetic studies in modern humans, and artificial intelligence, we discovered substantial genetic differences in the circadian systems of Neanderthals and modern humans,” said the paper’s lead author, John A. Capra. “Then by analyzing the bits of Neanderthal DNA that remain in modern human genomes we discovered a striking trend: many of them have effects on the control of circadian genes in modern humans and these effects are predominantly in a consistent direction of increasing propensity to be a morning person. This change is consistent with the effects of living at higher latitudes on the circadian clocks of animals and likely enables more rapid alignment of the circadian clock with changing seasonal light patterns. Our next steps include applying these analyses to more diverse modern human populations, exploring the effects of the Neanderthal variants we identified on the circadian clock in model systems, and applying similar analyses to other potentially adaptive traits.”

The paper “Archaic Introgression Shaped Human Circadian Traits” is available (at midnight on December 14, 2023) at: https://doi.org/10.1093/gbe/evad203.

Ancient genomics and Indigenous Knowledge reveal history of Coast Salish “woolly dogs"

 

Peer-Reviewed Publication

AMERICAN ASSOCIATION FOR THE ADVANCEMENT OF SCIENCE (AAAS)

DNA analysis of a 19th-century dog, paired with traditional knowledge acquired through interviews, have together provided new insights into the decline of Coast Salish “woolly dogs” – an extinct Indigenous dog once bred for its unique woolly coat. Dogs were introduced to the Americas at least 15,000 years ago and have been ubiquitous in Indigenous societies across the continents for thousands of years. Coast Salish peoples – a group of Indigenous societies that lived in the Salish Sea region of the Pacific Northwest (PNW) – kept several different types of dogs, including a special lineage of “woolly dogs” which had a thick woolen undercoat that was shorn for weaving blankets and textiles. However, due to increasing settler colonialism, the Coast Salish dog-wool weaving tradition declined throughout the 19th century; the Indigenous population of woolly dogs was lost. As a result, very little is known about these dogs, including their ancestry, the genetic underpinnings of their woolliness, and the factors that led to their ultimate disappearance. To address these questions, Audrey Lin and colleagues performed genomic and isotopic analyses on the only known pelt of an extinct Coast Salish dog, which belonged to a dog named Mutton that died in 1859. By comparing the genome sequence with other pre-Columbian and modern dog breeds, Lin et al. found that Mutton’s mitochondrial DNA was most similar to other pre-European contact lineages. According to the findings, Mutton’s genome showed limited introgression from European colonial dogs and, in general, lacked much genetic diversity, making Mutton the only known example of an Indigenous North American dog with dominant precolonial ancestry postdating the onset of European settlement in the area. Given the ubiquity of European ancestry present in many dog breeds at the time, the findings suggest that the Coast Salish peoples carefully and successfully maintained the genetic integrity of the woolly dog’s genetic lineage for a substantial period after first contact with colonizers. Moreover, the authors identified several candidate genetic variants linked to the dog’s distinctive woolly hair.

 

Working closely with Coast Salish Indigenous groups and incorporating these findings with traditional knowledge and historical records, Lin et al. were able to illustrate the cultural importance of the woolly dog and the drivers underlying their decline and extinction. Drivers included depopulation and forced migration of Indigenous peoples as well as colonial policies designed to disenfranchise and criminalize Coast Salish knowledge and cultural practices, including woolly dog husbandry. “The study from Lin et al. is exemplary for its engagement with local Indigenous communities,” writes Ludovic Orlando in a related Perspective. “Traditional Knowledge keepers were not just consulted for legal approval – a common concern for many studies – but their insights were recorded throughout the process as research material and directly embedded in the main text of the article.”

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JOURNAL

Science

DOI

10.1126/science.adi6549 

Vikings in Sweden suffered from tooth decay

 

Lesions and abrasions on teeth reveal dental problems and attempted treatments

Peer-Reviewed Publication

PLOS

 

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EXAMINATION OF VIKING JAW AND TEETH.

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CREDIT: CAROLINA BERTILSSON, CC-BY 4.0 (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

Vikings in Sweden suffered from painful dental issues and occasionally tried to treat them, according to a study published December 13, 2023 in the open-access journal PLOS ONE by Carolina Bertilsson of the University of Gothenburg, Sweden and colleagues.

In 2005, excavations in Varnhem, Sweden uncovered the remains of a Christian church, nearby which was a cemetery containing thousands of Viking graves dating to the 10th-12th century AD. In this study, Bertilsson and colleagues performed clinical and radiographical examination of the dentition of individuals from this site. In total, the team analyzed over 2300 teeth from 171 individuals. 

Over 60% of the examined adults had signs of dental caries (tooth decay), most often on the root surface, while none of the juvenile individuals had caries. Other pathologies were also observed, including tooth infection and indications of teeth having been lost before death. Several individuals had caries severe enough to have caused tooth pain, and the authors noted a few cases of tooth abrasion that were likely intentional modifications intended to lessen tooth pain. Some teeth also exhibited abrasions consistent with tooth picking, likely to remove bits of food.

The prevalence of dental caries in this population is similar to what has been noted in other European populations of a similar age, although the authors caution that nearly a quarter of these Varnhem individuals’ teeth appear to have been lost before or after death, and this likely skews these results. For example, the prevalence of caries in this population was observed to decrease with adults’ age, an unexpected result which likely reflects increased tooth loss in older individuals such that the most decayed teeth were not present. Overall, these data provide insights into the lives of Vikings who suffered from and occasionally attempted to treat dental issues, as well as providing details into the pathology of untreated dental issues.

The authors add: “In a Swedish Viking population, around half of the individuals suffered from dental caries. The Vikings performed both tooth filing, tooth picking, and other dental treatment, including attempts to treat dental infections.”

the freely available article in PLOS ONE: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0295282

Earliest evidence for domestic yak found using both archaeology, ancient DNA

 

 

IMAGE: 

XINYI LIU, ASSOCIATE PROFESSOR OF ARCHAEOLOGY, WASHINGTON UNIVERSITY IN ST. LOUIS

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CREDIT: SEAN GARCIA, WASHINGTON UNIVERSITY IN ST. LOUIS

The high-altitude hero of the Himalayas, yak are among the few large animals that can survive the extremely cold, harsh and oxygen-poor conditions of the Tibetan Plateau. In the mountainous regions of Asia, yak and yak-cattle hybrids serve as vital sources of meat, milk, transportation and fuel. However, little is known about their history: when or where yak were domesticated.

In a study published Dec. 13 in Science Advances, an international team of researchers that includes archaeologists at Washington University in St. Louis report archaeologically and genetically confirmed evidence for domestic yak, dating back 2,500 years, by far the oldest record.

The researchers zeroed in on this date using ancient DNA from a single male yak that lived alongside domestic cattle and yak-cattle hybrids in a settlement known as Bangga, a community in the southern Tibetan Plateau located at an elevation of approximately 3,750 meters (12,300 feet) above sea level.

“Many scholars have speculated that yak was first domesticated in the high-altitude regions of the Tibetan Plateau,” said Xinyi Liu, an associate professor of archaeology in Arts & Sciences at Washington University. “It was a well-informed speculation, but up to this point, there hasn’t been robust evidence for that,” Liu said. “This is the first evidence supported by both archaeology and ancient DNA.”

From unknown origins

Once widespread in the Tibetan Plateau, wild yak are now listed as “vulnerable” by the International Union for Conservation of Nature, with only an estimated 7,500 to 10,000 mature individuals left in the wild.

Domesticated yak, however, are prevalent across much of the world. An estimated 14 million to 15 million live in the highlands of Asia alone.

Scientists have previously traced the origins of other domestic bovine species found in Asia. This includes the taurine cattle found primarily in Europe and temperate areas of Asia; indicine cattle, or zebus, found primarily in India and tropical areas of Asia; and water buffalos in East and Southeast Asia. “Yak remains an open inquiry,” Liu said.

“Identifying domestic yak and yak-cattle hybrids at Bangga is not only essential to the understanding of the origin of this charismatic creature, the yak, but also informs us in general about animal domestication pathways, in which gene flow between related stocks is increasingly appreciated,” he said.

A transdisciplinary approach

Bangga is one of the earliest agro-pastoral settlements in the southern Tibetan Plateau and the only site in the region with abundant animal remains to have been systematically excavated in recent decades. This work at Bangga, led by Hongliang Lu from Sichuan University, has provided scientists with a glimpse of daily lives at extremely high elevations between 3,000 and 2,000 years ago, contributing excellent momentum around improving our knowledge about the ancient Himalayan region.

The excavations at Bangga also offer a rare opportunity to explore the history of early yak, cattle and their hybrids. For this study, Liu and his fellow archaeologists paired up with livestock geneticists. The team used ancient DNA sequencing as well as zooarchaeological analysis and radiocarbon measurements to help answer questions that could not be resolved with field analysis alone. “Our research at Bangga is a good example of the transdisciplinary and internationally collaborative nature of the 21st century archaeology,” Liu said.

Starting with more than 10,000 pieces of mammal bones collected at Bangga, Zhengwei Zhang, an alumnus of Washington University who is now a postdoctoral researcher at Sichuan University, identified and sorted out 193 specimens belonging to the genus Bos, a group that includes all domestic cattle, zebus and yak, as well as their wild progenitors, aurochs.

The researchers subsequently selected five well-preserved bones from these Bos samples to sequence for whole-genomic ancestry. The sequencing work was led by Ningbo Chen and Chuzhao Lei, two leading geneticists at Northwest A&F University who specialized in Bos domestication.

Genetic analysis revealed that only one of the ancient bones came from a yak, a male individual, while the other four bones were from female taurine cattle. Even figuring out that the cattle were taurine cattle was a surprise, Liu said, as Bangga is located close to the Himalayas and within the range of zebus and Indian aurochs, which were not found at Bangga. Instead, the cattle belonged to the taurine lineage that was introduced to the region from Anatolia via the silk route and northern Tibetan Plateau.

Additional analysis helped clarify that the bone from the male yak was truly a domestic variant, and not just a bone from a wild yak that hunters had killed and brought back to the settlement as food. The researchers also saw evidence for hybridization between the two species.

Bringing yak home

This new discovery of domesticated yak from 2,500 years ago fits into the larger story that is beginning to emerge about how humans adapted to living in a high-altitude environment on the Tibetan Plateau. For example, Liu and his colleagues have previously documented how people in this region grew barley as they faced a challenging environment.

“Bangga provided us with a unique window into lifeways at high elevations 3,000 to 2,000 years ago,” Liu said. “They cultivated barley in an intensive way, provisioned sheep with fodder and water and consumed milk. All these resources were introduced to the Tibetan Plateau from other world regions as part of prehistoric food globalization and had become part of the Tibetan legacy. Now we know they had domestic yak.”

This discovery of the genetically confirmed evidence of domestic yak does not yet solve all questions about yak domestication, nor does it necessarily represent the very beginning of that domestication process. However, it hints at what motivated herders to bring yak home.

Early herders in this region were likely faced with harsh conditions, where animals died out quickly because of prolonged winters and severe snow storms. One would need to be innovative, living in such conditions. A possible solution is intensive corralling, which would have allowed herders to provision their herds with agricultural by-products and water year-round. This strategy is attested by recent zooarchaeological and isotopic work led by Liu and Zhang.

The other solution would be to combine the environmental hardiness of yak with the productivity of cattle. “Dzomo (female hybrid) and dzo (male) are still the most common stocks in the Plateau even today for that reason. Cattle produce more milk and meat, but they are not as good at adapting to the high-altitude environment as yak,” Liu said. “Hybridization allows cattle to move high, and yak to move low at the same time they produce more milk.”

Study co-author Fiona Marshall, professor emerita of Washington University and a world-leading expert on animal domestication, said the study draws attention to the genetic continuity among domestic yak and taurine cattle on the Tibetan Plateau. In many regions of the world, early domesticated animals were replaced by later varieties. The genomic data suggests such faunal turnover did not happen on the Tibetan Plateau.

“This suggests a successful and long-lasting legacy of early Tibetan communities who were cosmopolitan in subsistence strategies and resilient and innovative in facing a challenging climate,” Liu said. “Bangga provides the best example of such a community.”

 

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JOURNAL

Science Advances

DOI

10.1126/sciadv.adi6857 

Archaeologists unearth one of earliest known frame saddles

 

IMAGE: 

SCIENTISTS UNCOVERED A ELEGANTLY CARVED SADDLE MADE FROM SEVERAL PIECES OF BIRCH WOOD FROM AN ANCIENT CAVE IN MONGOLIA.

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CREDIT: WILLIAM TAYLOR/ CU BOULDER

In April 2015, looters sacked an ancient cave burial at a site called Urd Ulaan Uneet high within the Altai Mountains of western Mongolia. When police apprehended the criminals, they uncovered, among other artifacts, an elegantly carved saddle made from several pieces of birch wood.

Now, in a new study, researchers from Mongolia collaborating with University of Colorado Boulder archaeologist William Taylor have described the find. The team’s radiocarbon dating pins the artifact to roughly the 4th Century C.E., making it one of the earliest known frame saddles in the world. 

“It was a watershed moment in the technological history of people and horses,” said Taylor, corresponding author of the new study and curator of archaeology at the CU Museum of Natural History.

He and his colleagues, including scientists from 10 countries, published their findings Dec. 12 in the journal Antiquity.

The research reveals the underappreciated role that ancient Mongolians played in the spread of horse riding technology and culture around the globe. Those advances ushered in a new and sometimes brutal era of mounted warfare around the same time as the fall of the Roman Empire. 

The discovery also highlights the deep relationships between human and animals in Mongolia. For millennia, pastoral peoples have traveled between the vast grasslands of the Mongolian Steppe with their horses—which, in the region, tend to be short but sturdy, capable of surviving winter temperatures that can plummet far below freezing. Airag, a lightly alcoholic beverage made from fermented horse milk, remains a popular libation in Mongolia.

“Ultimately, technology emerging from Mongolia has, through a domino effect, ended up shaping the horse culture that we have in America today, especially our traditions of saddlery and stirrups,” Taylor said.

But these insights also come at a time when Mongolia’s horse culture is beginning to disappear, said study lead author Jamsranjav Bayarsaikhan. 

“Horses have not only influenced the history of the region but also left a deep mark on the art and worldview of the Nomadic Mongols,” said Bayarsaikhan, an archaeologist at the Max Planck Institute for the Science of Human History in Germany. “However, the age of technology is slowly erasing the culture and use of horses. Instead of herders riding horses, more and more people are riding motorcycles in the plains of Mongolia.”

Mounted combat

Bayarsaikhan was working as a curator at the National Museum of Mongolia when he and his colleagues got the call from police in Hovd Province. The team later excavated the Urd Ulaan Uneet cave and unearthed the mummified remains of a horse, which the group partially described in a 2018 paper.

The saddle itself was made from about six pieces of birch wood held together with wooden nails. It bears traces of red paint with black trim and includes two leather straps that likely once supported stirrups. (The researchers also reported an iron stirrup recently discovered from around the same time period in eastern Mongolia).

The group couldn’t definitively trace back where those materials came from. Birch trees, however, grow commonly in the Mongolian Altai, suggesting that locals had crafted the saddle themselves, not traded for it.

Taylor explained that humans had used pads, a form of proto-saddle, to keep their rear ends comfortable on horseback since the earliest days of mounted riding. Rigid wooden saddles, which were much sturdier, paired with stirrups opened a new range of things that people could do with horses. 

“One thing they very gave rise to was heavy cavalry and high-impact combat on horseback,” Taylor said. “Think of jousting in Medieval Europe.”

Traveling west

In the centuries after the Mongolian saddle was crafted, these types of tools spread rapidly west across Asia and into the early Islamic world. There, cavalry forces became key to conquest and trade across large portions of the Mediterranean region and northern Africa. 

Where it all began, however, is less clear. Archaeologists have typically considered modern-day China the birthplace of the first frame saddles and stirrups—with some finds dating back to the 5th to 6th Century C.E. or even earlier.

The new study, however, complicates that picture, Taylor said. 

“It’s not the only piece of information suggesting that Mongolia might have been either among the very first adopters of these new technologies—or could, in fact, be the place where they were first innovated,” he said.

He suspects that Mongolia’s place in that history may have gone underappreciated for so long in part because of the region’s geography. The population density in the country’s mountainous expanses is low, among the lowest on Earth, making it difficult to encounter and analyze important archaeological finds. 

Bayarsaikhan, for his part, calls for more archaeological research in the nation to better tell the story of horses in Mongolia. 

“Mongolia is one of the few nations that has preserved horse culture from ancient times to the present day,” he said. “But the scientific understanding of the origin of this culture is still incomplete.”

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JOURNAL

Antiquity

DOI