Thursday, July 25, 2024

Genetics reveal ancient trade routes and path to domestication of the Four Corners potato

 

Genetic analysis shows that ancient Indigenous people transported, cultivated and may have domesticated the native tuber outside of its natural distribution, reflecting the enduring ecological legacy of Indigenous people in the Southwestern U.S.

Growing the Four Corners potato 

IMAGE: 

ALASTAIR LEE BITSÓÍ, DINÉ, WITH FOUR CORNERS POTATOES AT HIS FARM IN THE NAVAJO NATION.

view more 

CREDIT: ALASTAIR LEE BITSÓÍ

A new study shows that a native potato species was brought to southern Utah by Indigenous people in the distant past, adding to an ever-growing list of culturally significant plant species that pre-contact cultures domesticated in the Southwestern U.S. 

The team of researchers, led by Red Butte Garden and the Natural History Museum of Utah (NHMU) at the University of Utah, used genetic analysis to reveal how and where tubers of the Four Corners potato (Solanum jamesii) had been collected, transported and traded throughout the Colorado Plateau. The findings support the assertion that the tuber is a “lost sister,” joining maize, beans and squash—commonly known as the three sisters—as a staple of crops ingeniously grown across the arid landscape.

“Transport is one of the early crucial steps in the domestication of native plants into crops," said Dr. Lisbeth Louderback, curator of archaeology for NHMU, associate professor of anthropology at the U and coauthor of the study. “Domestication can begin with people gathering and replanting propagules in a new location.”

The authors collected DNA samples from modern Four Corners potato populations near archaeological sites and from non-archaeological populations within the potato's natural range in the Mogollon Rim of central Arizona and New Mexico. The findings indicate that the potato was transported and cultivated, likely by the ancestors of modern Pueblo (Hopi, Zuni, Tewa, Zia), Diné, Southern Paiute and Apache tribes. 

"The Four Corners potato, along with maize, cacao, and agave, reflects the significant influence of humans on plant diversity in the landscape over millennia,” said Dr. Bruce Pavlik, former director of conservation at Red Butte Garden and lead author of the study.

The paper published on July 12, 2024, in the American Journal of Botany.

S. jamesii has twice the protein, calcium, magnesium and iron content than an organic red potato, and a single tuber can grow to yield up to 600 small tubers in just four months. The nutritious crop would have been a highly valued trade item and crucial in the lean winter months. While the unique distribution of the Four Corners potato came as a surprise to scientists and researchers, local Tribal members suspected this all along. 

“The Southwest was an important, overlooked secondary region of domestication. Ancient Indigenous People were highly knowledgeable agriculturalists tuned into their regional ecological environs who traded extensively and grew the plants in many different environments,” said Wendy Hodgson, herbarium curator and research botanist at the Desert Botanical Garden. “Such studies highlight the need to learn from Indigenous Peoples’ perspectives, ethnographic reports, and to view landscapes and some plant species from a cultural, rather than ‘natural’, perspective.”

The lost sister

The Mogollon Rim region encompasses southcentral Arizona, extending east and north into the Mogollon Mountains of New Mexico. Jagged limestone and sandstone cliffs break up the ponderosas, pinyons and junipers scattered across the high-altitude terrain. S. jamesii is widely distributed across the Rim—the plants thrive in conifer woodlands, and thousands of small tubers can grow beneath a single pinyon pine canopy. These “non-archaeological” populations lack an association with artifacts, grow to be quite large and are continuously distributed across the habitat. 

In contrast, “archaeological populations” of the potato occur within 300 meters of ancient habitation sites and tend to be smaller than in the species’ central distribution. The sparse, isolated populations across the Colorado Plateau exhibit a genetic makeup only explained by human gathering and transport.

“Tribes of the Four Corners region have nurtured a connection to food and landscape biodiversity since time immemorial,” said Alastair Lee Bitsóí (Diné), a Navajo journalist who grows and reports on the Four Corners potato. “I've grown spuds from Bears Ears, Grand Staircase and Mesa Verde region at my family's farm in the Navajo Nation, and from them a new generation has been born. Like the ancestors, I am a dispersal agent for its transport and cultivation.”

To reproduce sexually—that is, to create viable seeds—flowers must receive pollen from a different plant with specific, compatible genetic factors. Without the right companion, plants will clone themselves by sprouting from underground stems to create a genetically identical daughter plant. Its cloning capability allows S. jamesii to persist even when conditions are far from ideal. It also provides a genetic stamp marking where each population originated. This signature is common in potatoes carried to locations with few other individuals and persists for hundreds of generations.

Researchers collected DNA samples from 682 individual plants across 25 populations of the Four Corner potato—14 populations were near archaeological sites, while 11 were from non-archaeological areas in its natural distribution. The results showed that the most genetically diverse populations of S. jamesii were concentrated around the Mogollon Rim. Conversely, populations from archaeological sites exhibited reduced genetic diversity because the transported tubers may have only contained a fraction of the available genes. 

Tracing the origins of archaeological populations

The authors found that populations of S. jamesii in Escalante Valley in Southern Utah have two different origins—one directly from the Mogollon Rim region and one related to Bears Ears, Mesa Verde and El Morro. These archaeological sites form a genetic corridor suggesting ancient people transported the tubers north south to north transport of tubers. 

Despite being close geographically, four archaeological populations around Escalante Valley show distinct origins. The genetic signatures could indicate that people transported potatoes to new locations multiple times in the distant past in a pattern likely corresponding to ancient trade routes.

“The potato joins a large assemblage of goods that were traded across this vast cultural landscape,” said Louderback. “For millennia, people of the southwest participated in social networks, migration and trade routes in the region.”

What is clear is that the species has been transported and grown far from its center of natural distribution. Scientists from the USDA Potato Gene Bank have been sampling the genetics of the Four Corner’s potato for decades and were intrigued by the diversity of genetic patterns along the geographic range.

“We used to wonder about the patterns of genetic diversity distribution of Solanum jamesii,” said Dr. Alfonso del Rio, plant geneticist at the University of Wisconsin-Madison and the U.S. Department of Agriculture Potato Genebank and coauthor of the study. “It wasn't clear to us that humans had altered its range, but now we have evidence confirming just that."

The researchers interpret the transport of the Four Corners potato as early stages of domestication, however, they plan to analyze specific gene sequences to learn more about S. jamesii.

“We’d like to look at specific genetic markers for certain desirable traits such as taste, tuber size and frost tolerance,” said Pavlik. “It's entirely possible that Indigenous people were preferring certain traits and thus trying to encourage favorable genes.”

“Agave, the Four Corners potato, and other domesticated species are excellent candidates for arid land cultivation at a time when we are faced with many challenges including food security and water resource availability,” said Hodgson. “As illustrated in this and other studies, protecting and understanding the distribution, and ecological and cultural roles of these plants require interdisciplinary collaboration between botanists, archaeologists, federal agencies and Indigenous Peoples.”


Wednesday, July 24, 2024

Hunter-gatherers kept an 'orderly home' in the earliest known British dwelling


Reconstructed dwelling of a hunter-gatherer community 

IMAGE: 

A RECONSTRUCTION OF WHAT A DWELLING FOR A HUNTER-GATHERER COULD HAVE LOOKED LIKE.

view more 

CREDIT: UNIVERSITY OF YORK, YEAR CENTRE

Archaeological evidence from the world-famous Mesolithic site of Star Carr in North Yorkshire has shown that hunter-gatherers likely kept an orderly home by creating ‘zones’ for particular domestic activities.

The research team from the University of York and the University of Newcastle, looked at microscopic evidence from the use of stone tools found inside three structures - potentially cone-like in shape or domed -  dating to over 11,000 years ago at the Star Carr site.

They found that there was a range of activities that were likely to have taken place inside the ‘home’, including wood, bone, antler, plant, hide, meat and fish related work.  The researchers then plotted out spatial patterns for these activities to pin-point where within the dwelling these activities might have occurred.

Dr Jess Bates, from the University of York’s Department of Archaeology said: “We found that there were distinct areas for different types of activity, so the messy activity involving butchery, for example, was done in what appears to be a designated space, and separate to the ‘cleaner’ tasks such as crafting bone and wooden objects, tools or jewellery.  

“This was surprising as hunter-gatherers are known for being very mobile, as they would have to travel out to find food, and yet they have a very organised approach to creating not just a house but a sense of home.  

“This new work, on these very early forms of houses suggests, that these dwellings didn’t just serve a practical purpose in the sense of having a shelter from the elements, but that certain social norms of a home were observed that are not massively dissimilar to how we organise our homes today.”

Previous work has also shown that there is evidence that hunter-gatherers kept their dwellings clean, as well as orderly, with indications that sweeping of the inside of the structure took place.

Star Carr provides the earliest known evidence of British dwellings and some of the earliest forms of architecture. One of the structures found was believed to be shaped like a cone and was constructed out of wood from felled trees, as well as coverings possibly made from plants, like reeds, or animal hides. There is still very little known about why hunter-gatherers would build such structures and continued to throughout the Mesolithic period.  

Dr Bates said: “Not only do we now know that hunter-gatherers were constructing these dwellings, but they had a shared group understanding of how to organise tasks within them. 

“In modern society we are very attached to our homes both physically and emotionally, but in the deep past communities were highly mobile so it is fascinating to see that despite this there is still this concept of keeping an orderly home space.

“This study shows that micro-scale analysis can be a really exciting way of getting at the details of these homes and what these spaces meant to those who lived there.”

The research is published in the journal PLOS One.

How Neanderthals ate birds: Scientists try to replicate ancient butchering methods

 

A scientist defeathers one of the birds 

IMAGE: 

A SCIENTIST DEFEATHERS ONE OF THE BIRDS. IMAGE BY DR MARIANA NABAIS.

view more 

CREDIT: DR MARIANA NABAIS.

It's hard to know what Neanderthals ate: food preparation, especially when it comes to smaller items like birds, can leave few archaeological traces. But understanding their diets is critical to understanding these incredibly adaptable hominins, who thrived for hundreds of thousands of years in wildly varied environments. To learn what food preparation could look like in the archaeological record, scientists tried cooking like Neanderthals.

“Using a flint flake for butchering required significant precision and effort, which we had not fully valued before this experiment,” said Dr Mariana Nabais of the Institut Català de Paleoecologia Humana i Evolució Social in Spain, lead author of the article in Frontiers in Environmental Archaeology. “The flakes were sharper than we initially thought, requiring careful handling to make precise cuts without injuring our own fingers. These hands-on experiments emphasized the practical challenges involved in Neanderthal food processing and cooking, providing a tangible connection to their daily life and survival strategies.”

You are what you eat

Although the big game hunting practiced by Neanderthals is well known, we know less about the birds that some Neanderthals hunted. But recent discoveries and new techniques allow us to investigate this more deeply. By testing food preparation methods that Neanderthals could have used, to see what traces these might leave on bones and how those traces compare to damage caused by natural processes or the actions of other animals, the scientists created an experimental database that can be compared to real archaeological sites.

The scientists collected five wild birds that had died of natural causes from the Wildlife Ecology, Rehabilitation and Surveillance Centre (CERVAS) in Gouveia, Portugal. They chose two carrion crows, two collared doves, and a wood pigeon, which are similar to species that Neanderthals ate, and selected cooking methods using archaeological evidence and ethnographic data.

All the birds were defeathered by hand. A carrion crow and a collared dove were then butchered raw, using a flint flake. The remaining three were roasted over hot coals until cooked, then butchered, which the scientists found much easier than butchering the raw birds.

“Roasting the birds over the coals required maintaining a consistent temperature and carefully monitoring the cooking duration to avoid overcooking the meat,” said Nabais. “Maybe because we defeathered the birds before cooking, the roasting process was much quicker than we anticipated. In fact, we spent more time preparing the coals than on the actual cooking, which took less than ten minutes.”

Putting flesh on prehistoric bones

The scientists cleaned and dried the bones, then examined them microscopically for cutmarks, breaks, and burns. They also examined the flint flake they had used for evidence of wear and tear. Although they had used their hands for most of the butchery, the raw birds required considerable use of the flint flake, which now had small half-moon scars on the edge. While the cuts used to remove meat from the raw birds did not leave traces on the bones, the cuts aimed at tendons left marks similar to those on birds found at archaeological sites.

The bones from the roasted birds were more brittle: some had shattered and couldn’t be recovered. Nearly all of them had brown or black burns consistent with controlled exposure to heat. Black stains inside some bones suggested that the contents of the inner cavity had also burned. This evidence sheds light not just on how Neanderthal food preparation could have worked, but also how visible that preparation might be in the archaeological record. Although roasting makes it easier to access meat, the increased fragility of the bones means the leftovers might not be found by archaeologists.

However, the scientists cautioned that this research should be expanded to gain a fuller understanding of Neanderthal diets. Future studies should include more species of small prey, as well as processing birds for non-food products, like talons or feathers.

“The sample size is relatively small, consisting of only five bird specimens, which may not fully represent the diversity of bird species that Neanderthals might have used,” noted Nabais. “Secondly, the experimental conditions, although carefully controlled, cannot completely replicate the exact environmental and cultural contexts of Neanderthal life. Further research with larger samples, varied species, and more diverse experimental conditions is necessary to expand upon these results.”

Tuesday, July 23, 2024

Dietary diversity of denisovans on Qinghai-Xizang Plateau

 A new study has revealed that Denisovans survived on the Qinghai-Xizang Plateau as late as 48,000–32,000 years ago, by butchering and consuming a diverse range of animals. This study, published in Nature and led by ZHANG Dongju from Lanzhou University, Frido Welker from the University of Copenhagen, and CHEN Fahu from the Institute of Tibetan Plateau Research of the Chinese Academy of Sciences, sheds light on Denisovan behavior and demonstrates how adaptable Denisovans were to the harsh and variable environment of the Qinghai-Xizang Plateau.

The Denisovans are an extinct species of ancient human, closely related to Neanderthals, who ranged across much of eastern Eurasia towards the end of the last ice age. The researchers studied more than 2,500 bones from the Baishiya Karst Cave on the high-altitude Qinghai-Xizang Plateau, one of only two places where Denisovans are known to have lived.

Most bone fragments excavated from the Baishiya Karst Cave are so fragmented that it is impossible to morphologically identify which species they are from. A proteomic screening method called Zooarchaeology by Mass Spectrometry (ZooMS) was therefore employed. It helped the researchers determine the species of most bone specimens based on small differences in the amino acid sequence of the protein collagen.

"ZooMS allows us to extract valuable information from often overlooked bone fragments, providing deeper insight into human activities," said Dr. XIA Huan from Lanzhou University. 

By combining molecular and traditional zooarchaeological analysis, the researchers determined that most of the bones were from blue sheep (also known as bharal), which is a species of caprine common to the Himalayas today. Other bone fragments came from large herbivores—such as wild yak, equids, and the extinct woolly rhino—and carnivores—such as the locally extinct spotted hyena. They also identified bone fragments from small mammals, such as marmots, and birds.  

Together, the animal species found in the Baishiya Karst Cave indicated that the area around the cave was dominated by a grass landscape with some small forested areas.

"Large amounts of bone remains were found in the cave. The diverse species identified partly answers the questions why Denisovans chose to live in the Baishiya Karst Cave and the surrounding Ganjia Basin, and how they survived there for hundreds of thousands of years," Prof. ZHANG said.

Many of the identified bone fragments showed cut marks and other traces of human activity, indicating that they had been processed by Denisovans. Detailed analysis of the bone surfaces revealed carcass processing evidence of Denisovan such as the removal of meat and extraction of bone marrow, preparation of animal hides, and even the use of bones as tool-making materials. The bones of the small mammals and birds also showed evidence of Denisovan activity.

"Current evidence suggests that it was Denisovans, not any other human groups, who occupied the cave and made efficient use of all the animal resources available to them throughout their occupation," said Dr. WANG Jian from Lanzhou University.

In addition, the researchers found a hominin rib bone using ZooMS analysis. Detailed shotgun proteomic analysis of all the proteins preserved in the bone revealed it to be a Denisovan fossil.

"Since we only know the Denisovans from a few fossils worldwide, they are still a bit of a mystery. Every new individual we discover therefore provides a significant piece to the puzzle of who they were, where they were living, and when!" said Dr. Zandra Fagernäs from the University of Copenhagen.

The layer where the rib was found was dated to between 48,000 and 32,000 years ago, implying that this Denisovan individual lived at a time when modern humans were dispersing across the Eurasian continent.

Collectively, the findings suggest that Denisovans lived at the Baishiya Karst Cave well into the Late Pleistocene.

"The long occupation of Denisovans at Baishiya Karst Cave, from the late Middle Pleistocene to the late Late Pleistocene, provides a good base for them to adapt to the high elevation environment characteristic of the Qinghai-Xizang Plateau," said Prof. CHEN.

Dr. Welker noted that Denisovans were on the plateau during two cold ice ages, and during a warmer interglacial period in between.

"The fossil and molecular evidence therefore indicated that Ganjia Basin where Baishiya Karst Cave is located, provides a relatively stable environment for Denisovans, despite its high altitude. The question now arises when and why these Denisovans on the Qinghai-Xizang Plateau went extinct," said Dr. Welker.

Saturday, July 20, 2024

New discovery adds to story of ancient human migration


New evidence of human occupation in southeast Indonesia dating back 42,000 years offers fresh clues on the route taken by some of the first humans to arrive in our region, according to a study from The Australian National University (ANU). 

Lead author and ANU PhD candidate Hendri Kaharudin said the location of the discovery -- at Elivavan on Indonesia’s Tanimbar islands -- makes it especially significant.  

“Tanimbar is located just off the ‘Sahul shelf’, which encompasses modern-day Australia, as well as New Guinea,” he said. 

“The question of how our early ancestors arrived there from Southeast Asia is one of the most captivating in prehistoric migration, mainly because of the vast distances covered and advanced seafaring skills that would have been required. 

“There are two main routes that have been explored as possibilities since the mid-20th century – a northern path via islands like Sulawesi, and a southern track passing near Timor and the Tanimbar islands. 

“This discovery marks one of the southern route’s earliest known sites, making it a crucial piece of the puzzle.”   

According to the researchers, while there are still unanswered questions about Elivavan’s first inhabitants, the risky nature of the sea crossings suggests the colonists had developed advanced maritime technology by around 42,000 years ago. 

“They would have had to traverse bodies of water exceeding 100 kilometres in distance, regardless of their direction of travel,” Mr Kaharudin said.  

“Along with tiny fragments of pottery we also found evidence of things like bones, shells and sea urchins that point to the island’s role as a hub for early maritime activities. 

“As more work is done in lesser-explored regions like the Tanimbar islands, I expect we’ll uncover more about early human life and migration patterns.”  

Mr Kaharudin said it’s also clear the colonisation of Sahul was not a single event but “a gradual process involving successive waves of seafaring populations”.  

“Coastal communities likely navigated shorelines, exploiting marine resources and establishing resilient settlements along their journey,” he said. 

“This island-hopping strategy facilitated cultural exchange and adaptation, shaping diverse societies across the land mass.” 

The study was conducted in collaboration with Indonesia’s National Research and Innovation Agency (BRIN). The research team also included Professor Sue O’Connor and Dr Shimona Kealy from ANU.  

The research has been published in Quaternary Science Reviews (QSR). 

“Tanimbar is located just off the ‘Sahul shelf’, which encompasses modern-day Australia, as well as New Guinea,” he said. 

“The question of how our early ancestors arrived there from Southeast Asia is one of the most captivating in prehistoric migration, mainly because of the vast distances covered and advanced seafaring skills that would have been required. 

“There are two main routes that have been explored as possibilities since the mid-20th century – a northern path via islands like Sulawesi, and a southern track passing near Timor and the Tanimbar islands. 

“This discovery marks one of the southern route’s earliest known sites, making it a crucial piece of the puzzle.”   

According to the researchers, while there are still unanswered questions about Elivavan’s first inhabitants, the risky nature of the sea crossings suggests the colonists had developed advanced maritime technology by around 42,000 years ago. 

“They would have had to traverse bodies of water exceeding 100 kilometres in distance, regardless of their direction of travel,” Mr Kaharudin said.  

“Along with tiny fragments of pottery we also found evidence of things like bones, shells and sea urchins that point to the island’s role as a hub for early maritime activities. 

“As more work is done in lesser-explored regions like the Tanimbar islands, I expect we’ll uncover more about early human life and migration patterns.”  

Mr Kaharudin said it’s also clear the colonisation of Sahul was not a single event but “a gradual process involving successive waves of seafaring populations”.  

“Coastal communities likely navigated shorelines, exploiting marine resources and establishing resilient settlements along their journey,” he said. 

“This island-hopping strategy facilitated cultural exchange and adaptation, shaping diverse societies across the land mass.” 

The study was conducted in collaboration with Indonesia’s National Research and Innovation Agency (BRIN). The research team also included Professor Sue O’Connor and Dr Shimona Kealy from ANU.  

The research has been published in Quaternary Science Reviews (QSR). 

Friday, July 19, 2024

Butchery of giant armadillo-like mammals in Argentina 21,000 years ago


Anthropic cut marks in extinct megafauna bones from the Pampean region (Argentina) at the last glacial maximum 

IMAGE: 

3D RENDERING OF THE PROBABLE BUTCHERY EVENT ACCORDING TO A PALEOARTISTIC RECONSTRUCTION. THE ILLUSTRATION WAS MADE BY MODELING THREE-DIMENSIONAL MESHES, 3D DIGITAL SCANNING, AND TEXTURING BY PROJECTION, BASED ON THE PROPORTIONS OF THE EXCAVATED FOSSIL MATERIALS AND THE RESULTS OBTAINED IN THE STUDY.

view more 

CREDIT: DAMIÁN VOGLINO, MUSEO DE CIENCIAS NATURALES A. SCASSO (COLEGIO DON BOSCO), SAN NICOLÁS DE LOS ARROYOS, PROVINCIA DE BUENOS AIRES, CC-BY 4.0 (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

Cut marks on fossils could be evidence of humans exploiting large mammals in Argentina more than 20,000 years ago, according to a study published July 17, 2024 in the open-access journal PLOS ONE by Mariano Del Papa of National University of La Plata, Argentina and colleagues.

The timing of early human occupation of South America is a topic of intense debate, highly relevant to a study of early human dispersal across the Americas and of humans’ potential role in the extinction of large mammals at the end of the Pleistocene Epoch. This discussion is hampered by a general scarcity of direct archaeological evidence of early human presence and human-animal interactions.

In this study, researchers present evidence of butchery on Pleistocene mammal fossils from the banks of the Reconquista River, northeast of the Pampean region in Argentina. The fossils are those of a glyptodont, a giant relative of armadillos, named Neosclerocalyptus. Statistical analysis finds that cut marks on parts of the pelvis, tail, and body armor are consistent with known marks made by stone tools, and the placement of these marks is consistent with a butchering sequence targeting areas of dense flesh. Radiocarbon dating indicates these fossils are around 21,000 years old, nearly six thousand years older than other known archaeological evidence in southern South America.

These results fit with other recent findings that indicate early human presence in the Americas over 20,000 years ago. These fossils are also among the oldest evidence of human interaction with large mammals shortly before many of those mammals became extinct. The authors suggest that these findings might be further supported by additional excavation at this site, further analysis of the cut marks, and more extensive radiocarbon dating of the fossils.

Miguel Delgado, the corresponding author, adds: "The study's evidence puts into question the time frame for the first human peopling of the Americas 16,000 years ago"

The freely available article in PLOS ONEhttps://journals.plos.org/plosone/article?id=10.1371/journal.pone.0304956 

Thursday, July 18, 2024

Another natural disaster may have made Vesuvius eruption even more deadly

 


Scientists think that skeletons of individuals trapped and killed inside buildings by earthquakes during the 79CE eruption of Vesuvius could provide a more complete history of destruction


Skeletons found in Pompeii 

IMAGE: 

SCIENTISTS DISCOVERED TWO SKELETONS IN THE RUINS OF A POMPEII BUILDING AND CONCLUDED THAT THEIR DEATHS MUST HAVE BEEN CAUSED BY WALL COLLAPSES TRIGGERED BY EARTHQUAKES. IMAGE: POMPEII ARCHAEOLOGICAL PARK.

view more 

CREDIT: IMAGE: POMPEII ARCHAEOLOGICAL PARK.

Almost 2,000 years ago, Pliny the Younger wrote letters describing a shaking ground as Vesuvius erupted. Now, a collaborative study led by researchers from the Istituto Nazionale di Geofisica e Vulcanologia (INGV) and Pompeii Archaeological Park has shed light on the effects of seismicity associated with the 79CE eruption.

The study is the first to tackle the complex task of reporting on the effects of co-occurring earthquakes. This is tricky due to the possibility of volcanic and seismic effects happening concurrently or in quick succession, meaning volcanic effects can overshadow effects caused by earthquakes and vice versa.

“These complexities are like a jigsaw puzzle in which all the pieces must fit together to unravel the complete picture,” said Dr Domenico Sparice, a volcanologist at INGV-Osservatorio Vesuviano and first author of the Frontiers in Earth Science study. “We proved that seismicity during the eruption played a significant role in the destruction of Pompeii and, possibly, influenced the choices of the Pompeiians who faced an inevitable death.”

Clues to a deadly collapse

“Correctly recognizing the cause-effect relationship is essential to reconstruct the interplay between volcanic and seismic phenomena, and their effects on buildings and humans,” added co-author Dr Fabrizio Galadini, a geologist and senior researcher at INGV.

During excavations in the ‘Casa dei Pittori al Lavoro’, the researchers noticed something off about the collapsed buildings. “We found peculiar characteristics that were inconsistent with the effects of volcanic phenomena described in the volcanological literature devoted to Pompeii. There had to be a different explanation,” said co-author Dr Mauro Di Vito, a volcanologist and director of INGV-Osservatorio Vesuviano.

When the researchers found two skeletons with severe fracture and trauma injuries, they were even more motivated to figure out the reason.

Painters at work

The eruption caught Pompeiians in the midst of daily life. For about 18 hours, pumice lapilli – small rock and ash particles– fell on the city, causing people to seek shelter. When the eruption paused, inhabitants who’d survived may have thought themselves safe – until strong earthquakes started.

“The people who did not flee their shelters were possibly overwhelmed by earthquake-induced collapses of already overburdened buildings. This was the fate of the two individuals we recovered,” said co-author Dr Valeria Amoretti, an anthropologist who heads the Applied Research Laboratory of Pompeii Archaeological Park.

The researchers found two male skeletons, both around 50 years of age. Their positioning suggests that ‘individual 1’ was suddenly crushed by the collapse of a large wall fragment, resulting in severe traumas causing immediate death. ‘Individual 2’, however, may have been aware of the danger and tried to protect himself with a round wooden object of which the researchers found faint traces in the volcanic deposits.

There are several hints that these individuals did not die from inhaling ash or extreme heat, such as their positioning on the pumice lapilli, rather than under it. This suggests both survived to first phase of the eruption and then were overwhelmed by collapsing walls during the temporary decline of the eruptive phenomena and before the arrival of the pyroclastic currents, the researchers said.

Difficult choices

While not everybody could make it into temporary safety, the numbers of victims recovered in the ash deposits makes people fleeing to the outside a plausible, albeit hopeless, scenario, the researchers said. There are no reliable estimations about how many people died from volcanic-related causes or due to damage caused by earthquakes.

“New insight into the destruction of Pompeii gets us very close to the experience of the people who lived here 2,000 years ago. The choices they made as well as the dynamics of the events, which remain a focus of our research, decided over life and death in the last hours of the city’s existence,” concluded co-author Dr Gabriel Zuchtriegel, director of the Pompeii Archaeological Park.