Thursday, July 14, 2022

DNA from ancient population in Southern China suggests Native Americans’ East Asian roots




For the first time, researchers successfully sequenced the genome of ancient human fossils from the Late Pleistocene in southern China. The data, published July 14 in the journal Current Biology, suggests that the mysterious hominin belonged to an extinct maternal branch of modern humans that might have contributed to the origin of Native Americans.

“Ancient DNA technique is a really powerful tool,” Su says. “It tells us quite definitively that the Red Deer Cave people were modern humans instead of an archaic species, such as Neanderthals or Denisovans, despite their unusual morphological features,” he says.

The researchers compared the genome of these fossils to that of people from around the world. They found that the bones belonged to an individual that was linked deeply to the East Asian ancestry of Native Americans. Combined with previous research data, this finding led the team to propose that some of the southern East Asia people had traveled north along the coastline of present-day eastern China through Japan and reached Siberia tens of thousands of years ago. They then crossed the Bering Strait between the continents of Asia and North America and became the first people to arrive in the New World. 

The journey to making this discovery started over three decades ago, when a group of archaeologists in China discovered a large set of bones in the Maludong, or Red Deer Cave, in southern China’s Yunnan Province. Carbon dating showed that the fossils were from the Late Pleistocene about 14,000 years ago, a period of time when modern humans had migrated to many parts of the world.

From the cave, researchers recovered a hominin skull cap with characteristics of both modern humans and archaic humans. For example, the shape of the skull resembled that of Neanderthals, and its brain appeared to be smaller than that of modern humans. As a result, some anthropologists had thought the skull probably belonged to an unknown archaic human species that lived until fairly recently or to a hybrid population of archaic and modern humans.

In 2018, in collaboration with Xueping Ji, an archaeologist at Yunnan Institute of Cultural Relics and Archaeology, Bing Su at Kunming Institute of Zoology, Chinese Academy of Sciences, and his colleagues successfully extracted ancient DNA from the skull. Genomic sequencing shows that the hominin belonged to an extinct maternal lineage of a group of modern humans whose surviving decedents are now found in East Asia, the Indo-China peninsula, and Southeast Asia islands.

The finding also shows that during the Late Pleistocene, hominins living in southern East Asia had rich genetic and morphologic diversity, the degree of which is greater than that in northern East Asia during the same period. It suggests that early humans who first arrived in eastern Asia had initially settled in the south before some of them moved to the north, Su says.

“It’s an important piece of evidence for understanding early human migration,” he says.

Next, the team plans to sequence more ancient human DNA by using fossils from southern East Asia, especially ones that predated the Red Deer Cave people.

“Such data will not only help us paint a more complete picture of how our ancestors migrate but also contain important information about how humans change their physical appearance by adapting to local environments over time, such as the variations in skin color in response to changes in sunlight exposure,” Su says.

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This study was supported by the National Natural Science Foundation of China, Chinese Academy of Sciences (CAS), the Kunming Institute of Zoology, CAS, Yunnan provincial “Ten Thousand Talents Plan-Youth Top Talent” project, and the Youth Innovation Promotion Association of CAS.

Current Biology, Zhang et al. “A Late Pleistocene human genome from Southwest China” https://www.cell.com/current-biology/fulltext/S0960-9822(22)00928-9

Current Biology (@CurrentBiology), published by Cell Press, is a bimonthly journal that features papers across all areas of biology. Current Biology strives to foster communication across fields of biology, both by publishing important findings of general interest and through highly accessible front matter for non-specialists. Visit http://www.cell.com/current-biology. To receive Cell Press media alerts, contact press@cell.com.

Thursday, July 7, 2022

Unlocking the secrets of the ancient coastal Maya

An interdisciplinary and international team of researchers is working  to uncover new insights about the dynamic interplay between social and natural processes that shaped life for these ancient, Maya people over the last 3,000 years. The team has just released a new article in the Journal of Island and Coastal Archaeology summarizing their findings to date.


“The Proyecto Costa Escondida,” which translates into English as the ‘hidden coast’ project, has focused on the ancient Maya port sites of Vista Alegre and Conil.

“We chose the project name because, the coast is literally hidden behind mangroves. We’ve canoed the coastline and you’ve really got to snake back to get to the site,” Glover said. “But at the same time, and more importantly, this region has been hidden from scholarship—there just hadn't been a lot of work done there until we arrived.”

To date, the work has produced a wealth of knowledge about maritime Maya civilization since 800 BCE (Before Common Era). Glover, an associate professor of Anthropology, is using an historical ecology framework to better understand the dynamic relationship between humans and the environment at the ancient Maya port sites of Vista Alegre and Conil.

“This is about how people respond to change,” said Dr. John Yellen, program director for archeology at the U.S. National Science Foundation, which helped fund the research. “Through the lens of historical ecology, this broad team of researchers has shown how Maya adapted over centuries to a wide range of environmental changes. This insight into one society’s long-term adaptation to coastal environments provides a fruitful model for studying such interactions across many cultures."

This region lies along Yucatan’s north coast, some hours from popular tourist attractions like Cancun and well-known archaeological sites like Chichen Itza and Tulum.

“What’s remarkable about our study area is that it represents one of the least developed coastlines on the northern Yucatan Peninsula,” said Rissolo, who was recently featured in a video series about the Maritime Maya. “When trying to understand the ancient maritime cultural landscape of the so-called ‘Riviera Maya,’ for example, your perspective is obscured by all-inclusive resorts, golf courses and theme parks. The shores of the Laguna Holbox, on the other hand, are still largely wild and offer a more unobstructed view into the region’s past.”

The site of Vista Alegre is a small island surrounded by mangroves that lies along the southern shore of the Holbox Lagoon (also called Conil or Yalahau Lagoon). Glover describes Vista Alegre as what was probably once a small, bustling port. Here, they’ve discovered and recorded as many as 40 rock-filled platforms that served as the foundation for perishable pole and thatch buildings. The largest is a pyramidal structure that stands about 13 meters—or nearly 43 feet—tall. Glover believes this probably served as a temple and a lookout where the site’s inhabitants could see if anyone was approaching by sea. Conil, on the other hand, is a much more expansive site located beneath the modern town of Chiquila and was encountered by early Spanish conquistadors who described it as a town of 5,000 houses.

Researchers have identified tens of thousands of artifacts and ecofacts (animal and plant remains that speak to past diets), which have helped improve our understanding of how the landscape has changed over time, how the people lived, and how they dealt with challenges not unlike those faced by people today, such as: rising sea levels and changing political and economic systems. “We are coordinating and synthesizing all the different datasets that we have, which gives us a wider-angle picture,” Glover said.

The project, which has been funded by the National Science Foundation (NSF) and the National Oceanic and Atmospheric Administration (NOAA), combines traditional archaeological techniques (think digging with a small hand trowel or shovel) with new, high-tech practices for land and sea. Glover says it is a matter of making the most out of the materials at hand.

“Archaeology requires a broad knowledge of the latest scientific techniques mixed with a strong reliance on ‘MacGyvering,’ Glover said. “We often utilize rustic equipment combined with high-tech tools. On any given day, we might find ourselves in a small dinghy borrowed from the local community out of which we are running marine geophysical survey equipment or pounding PVC tubes into the sediments with a homemade fencepost driver.”  

The complex work of marine geoarchaeology was spearheaded by Dr. Beverly Goodman-Tchernov and Dr. Roy Jaijel of the University of Haifa in Israel. The core samples include sediment from the coastline and give researchers a better idea of how the coastline has changed over time by looking at a host of different datasets. In particular, the remains of tiny creatures (foraminifera) are preserved in the cores. These creatures lived in very specific environments, so by finding certain species of foraminifera, the team can reconstruct what the coastal environment was like. Instead of being hidden as it is today, Vista Alegre was most likely once more open and purposely built on a peninsula that jutted into the lagoon making it a more obvious destination for ancient canoe-based traders.

Along with paleo-coastline reconstruction, Dr. Patricia Beddows of Northwestern University has been combing research on the modern hydrological system with oxygen isotope values from the core sediments to study how access to freshwater changed over time as a result of rising sea-levels. The team has to bring all of their drinking water with them to the site, so they are keenly aware what a limiting factor freshwater access could have been for past peoples. One idea is that there were springs near the site in the past that have been effectively drowned by rising sea level. To try to identify freshwater seeps (that are about two degrees Celsius cooler than the ocean water) the team is using a drone equipped with a thermal camera to identify areas that might represent past sources of freshwater.

The team also uncovered tens of thousands of pieces of pottery and hundreds of pieces of obsidian (volcanic glass used to make tools that can be traced to its original geologic location), which reveal these coastal peoples were involved in extensive trade. Glover says the diversity of these artifacts stands out when compared to that of nearby, inland sites. The research team believes the archaeological data reinforce the idea that these coastal peoples had much broader and more cosmopolitan connections because they were part of long-distance, canoe-based trade networks.

These trade connections are most evident about 1,000 years ago when researchers see a major realignment and expansion in international trade associated with the emergence of Chichen Itza as a powerful religious, political, and economic city.

“Strong evidence of this realignment comes from the obsidian data which reveals greater connections to parts of central Mexico, near modern day Mexico City” Glover said.

Many of these artifacts come from poring over the detritus—or garbage—left behind by this past civilization, Glover says this is often an archeologist’s goldmine. Mixed with the pottery and obsidian, the research team found items like spindle whorls, that would have been used to make cotton thread which could have been traded as bolts of cloth or used for fishing lines or nets.

When asked what is missing, Rissolo said “We would love to find an intact ancient Maya trading canoe! It’s possible that such a vessel may be preserved beneath the muddy bottom of the bays surrounding Vista Alegre. We would learn so much about these legendary watercraft.”

The team also discovered an array of natural materials, including more than 20,000 animal bones, from sharks, rays, turtles and marine gastropods (gastropods include animals like conchs and whelks which have been studied by another project leader, Dr. Derek Smith). The team is working closely with Mexican archeologists at the Autonomous University of Yucatan in Merida, Mexico to analyze the animal remains and burial sites that have been discovered.

Research came to a halt during much of the pandemic, but after months of excavations and discovery of so many artifacts, the team is still working to analyze their findings. Glover said they are also in discussions with local leaders in Mexico to create a community museum to highlight the region’s rich cultural and natural history.

Often, when people think about the ancient Maya, they may picture some sudden, cataclysmic event that upended daily life and led to end of this past, advanced civilization. Glover notes that this could not be further from the truth. Maya peoples are alive and well today in the Yucatan, Belize, and Guatemala. While the ‘collapse’ of Maya kingdoms between 800 and 900 CE often gets blown out of proportion in popular media, that does not mean that were not changes in settlements over time.

“I think it's a story, not of a sudden or mass exodus, but a shift over time,” Glover explained, “and to understand these shifts we must understand the complex interplay of environmental and cultural factors, which is what our research is revealing.”

The research also highlights the specific lifestyles and adaptive strategies needed to live in a dynamic coastal environment and how this fostered a shared identity amongst coastal Maya communities.

“Our research gives us some idea of the shared challenges that coastal peoples faced – rising sea-levels, diminished freshwater, changing economic and political systems - and they probably leaned on one another, Glover said. “In some ways, I think it might have been easier to hop in your canoe and paddle down the coast to seek help than it was to walk over land.”

“The past, just like the present is not static, and these people were constantly having to make decisions. Sometimes those decisions meant sticking it out, and sometimes they meant re-establishing their lives right down the coast. This new article is a great summation of what we have learned to date. But, you know, there's always more to be done, and we certainly have plans to continue.” Glover said.

Later this year, the team will start a new project with Dr. Tim Murtha, a colleague at University of Florida, to conduct a light detection and ranging (LIDAR) survey. They will collect detailed elevation data that can reveal the distribution of ancient Maya settlements like house mounds or pyramids. While not focused on the coast, the project will help the team better understand the relationship between inland and coastal communities.

Please visit http://costaescondida.org for more information on the project. 

On this project, Glover and Rissolo teamed with Dr. Patricia Beddows (Northwestern University), Dr. Beverly Goodman (University of Haifa), Dr. Derek Smith (University of Washington), and others under the auspices of Mexico’s National Institute of Anthropology and History (INAH).

Wednesday, July 6, 2022

Tooth isotopes offer window into South Australia’s early colonial history

 

Published in Australian Archaeology, the new research involved isotope analysis of teeth excavated from graves to determine how many people buried were born in South Australia or Britain, as part of scientific efforts by Flinders University experts deploying this technique for the first time in the state.

The archaeologists studied the origin of people in a free ground section of the cemetery to help construct a clear picture of colonial migration before 1880.

Lead Author and Flinders University Masters student, Christine Adams, says tooth enamel and dentine samples from the graves show one person was likely born in Adelaide, eight were originally from Britain and Ireland, and three could have been from either location.

“Only one person was likely born elsewhere according to our results. A total of 52 samples were tested, four samples per individual—26 for strontium, 26 for oxygen, and for both enamel and dentine. Strontium isotope samples were successfully analysed from the enamel and dentine of all individuals.

The finding that all individuals in this study may have, based on at least one isotope and dental material and supported by dietary data from the time, come from either Adelaide or the United Kingdom correlates well with the overwhelmingly British origin of colonists in South Australia and the cemetery’s own records before 1880.”

Flinders University co-author Associate Professor Ian Moffat says the study proves how isotope methods can be used to test the origin of case studies around Australia.

“This research technique is important for provenance studies where individuals could have migrated or moved substantial distances,” he says. “This study also shows that strontium isotope methods can be used to test a specific hypothesis rather than just being used to confirm a general location.”

Co-author and leader of the St Mary’s research project, Flinders University’s Professor Donald Pate, says the analysis combined a range of isotope investigations with further analysis of diets from previous studies.

“As the life history of these individuals is not well-documented in historical records, isotopic data provides important information about migration and mobility in a colonial South Australian population,” says Professor Pate.

“Our records and data suggest the majority of individuals interred within the free ground section of St Mary’s were either born in Britain or South Australia, but some may have migrated from other locations. Burial samples total 70 individuals at the cemetery, but degraded and missing tooth elements mean not all were suitable for investigation.”

Professor Pate is a veteran of studies at the site. At the request of the church, research began at St Mary’s Cemetery 20 years ago, with archaeologists painstakingly recovering remains from the free ground section ever since.

Friday, July 1, 2022

New genetic research on remote Pacific islands yields surprising findings on world’s earliest seafarers

 

New genetic research from remote islands in the Pacific offers fresh insights into the ancestry and culture of the world’s earliest seafarers, including family structure, social customs, and the ancestral populations of the people living there today.

The work, described in the journal Science, reveals five previously undocumented migrations into a subregion of this area and suggests that about 2,500 to 3,500 years ago early inhabitants of these Pacific islands — including Guam in the northern region and Vanuatu in the southwest — had matrilocal population structures where women almost always remained in their communities after marriage while men more often moved out of their mothers’ community to live with that of their wives’.

The practice is different from that of patrilocal societies where women are overwhelming the ones to leave their own community. These findings support the idea that the world’s earliest seafarers were organized through female lineages.

The results come from a genome-wide analysis on 164 ancient individuals from 2,800 to 300 years ago as well 112 modern individuals. It was published by a team of researchers co-led by Harvard geneticists David Reich and Yue-Chen Liu, Ron Pinhasi at the University of Vienna, and Rosalind Hunter-Anderson, an independent researcher working in Albuqueque New Mexico.

“It’s an unexpected gift to be able to learn about cultural patterns from genetic data,” said David Reich, a professor in the Department of Human Evolutionary Biology and a professor of genetics at Harvard Medical School. “Today, traditional communities in the Pacific have both patrilocal and matrilocal population structures and there was a debate about what the common practice was in the ancestral populations. These results suggest that in the earliest seafarers, matrilocality was the rule.

The genetic analysis compared early seafarers from Guam, Vanuatu, and Tonga — living about 2500 to 3,000 years ago — revealing that their mitochondrial DNA sequences, which humans only inherit from their biological mother, differed almost completely while sharing much more of the rest of their DNA. The only way this can happen is if migrants who left their communities to marry into new ones were almost always males.

“Females certainly moved to new islands, but when they did so they were part of joint movements of both females and males” explains Reich. “This pattern of leaving the community must have been nearly unique to males in order to explain why genetic differentiation is so much higher in mitochondrial DNA than in the rest of the genome.”

The new study from an interdisciplinary team of geneticists and archeologists quintuples the body of ancient DNA data from the vast Pacific region called Remote Oceania, the last habitable place on earth to be peopled. It also provides surprising insights into the extraordinarily complex peopling of one of Remote Oceania’s major subregions.

Humans arrived and spread through Australia, New Guinea, the Bismarck Archipelago, and the Solomon Islands beginning 50,000 years ago, but it wasn’t until after 3,500 years ago that humans began living in Remote Oceania for the first time after developing the technology to cross open water in unique long-distance canoes.

This expansion included the region called Micronesia: about two thousand small islands north of the Equator including Guam, the Marshall Islands, the Caroline Islands, Palau, and the Northern Mariana Islands.

It’s long been a mystery what the routes people took to arrive in the region. The revealing of five streams of migration into Micronesia helps bring clarity to this mystery and the origins of the people there today.

“These migrations we document with ancient DNA are the key events shaping this region’s unique history,” said Liu, a post-doctoral fellow in Reich’s lab and the study’s lead author. “Some of the findings were very surprising.”

Of the five detected migrations, three were from East Asia, one from Polynesia, and a Papuan ancestry coming from the northern fringes of mainland New Guinea. The indigenous ancestry from New Guinea was a major surprise as a different stream of this migration — one from New Britain, an island chain to the east of New Guinea —was the source of the Papuan ancestry in the southwest Pacific and in Central Micronesia.

The researchers also found that present-day Indigenous people of the Mariana Islands in Micronesia, including Guam and Saipan, derive nearly all their pre-European-contact ancestry from two of the East Asian-associated migrations the researchers detected. It makes them the “only people of the open Pacific who lack ancestry from the New Guinea region,” Liu said.

The researchers consulted with several Indigenous communities in Micronesia for the study. This is the fourth publication of original ancient DNA data from remote Pacific islands by Reich’s group.

“It’s important that when we do ancient DNA work, we don’t just write a paper about the population history of a region and then move on,” Reich said. “Each paper raises as many new questions as it answers, and this requires long term commitment to follow up the initial findings. In the Pacific islands there are so many open questions, so many surprises still to be discovered.”

Wednesday, June 29, 2022

Ancient DNA and teeth show: Romans brought mules with them

The Romans were the first to bring mules to Central Europe. Before they took mules northward across the Alps in the first century, horses were the only riding animals used by the peoples there. This was revealed by genetic analyses conducted by a research group from the ArchaeoBioCenter at LMU, the State Collection for Paleoanatomy Munich, and the University of Vienna.

 

Until the end of the Iron Age in the first century before Christ, the peoples in Celtic settlements in the northern Alpine foothills exclusively bred horses. Highly prized by the Celts as “animals for the elite,” horses were chiefly used for military operations. When Romans pushed into the regions north of the Alps shortly before the birth of Christ and settled there, they took mules with them from the Mediterranean area. Mules were esteemed by the military as pack and work animals. Romans valued the horse-donkey hybrids particularly for their strength, endurance, and sure-footedness in mountainous terrain. In addition, mules can survive on less valuable feed and are more resistant to diseases than horses and donkeys.

 

Before now, the beginning of the economic and military significance of mules for the peoples in settlement regions north of the Alps was fraught with uncertainties. Even for experts, it is tricky to distinguish the archeological remains of Equidae – that is to say, horses, donkeys, and their hybrids, mules and hinnies – from each other. Most skeleton parts of animals from this family are just too similar. A team of researchers from the Chair of Paleoanatomy, Domestication Research, and the History of Veterinary Medicine at LMU, the University of Vienna, and the State Collection for Paleoanatomy Munich has now investigated ancient DNA from more than 400 equids from one Celtic and seven Roman settlements in the northern provinces of the Roman Empire – today’s southern Germany, eastern Switzerland, and Austria.

 

The researchers compared the genetic analyses with the results of traditional methods of species identification – analysis of the morphology, shape, and size of mandibular teeth and particular bones. Remains of mules were found only in the Roman settlements. Furthermore, the investigations revealed that mules can be identified not only from their ancient DNA, but also through the characteristics of their premolar teeth in particular.

 

“However, the secure identification of the horse-donkey hybrids is contingent upon access to comprehensive reference collections of equid skeletons, so that researchers can compare them against archeological finds,” explains Joris Peters, Director of the State Collection for Paleoanatomy Munich and Chair of Paleoanatomy at LMU. “DNA is not always sufficiently well preserved in archeological material to be able to identify animals with certainty. Building up comprehensive natural history collections is therefore also essential for research into past cultures.”

Dogs are more genetically similar to ancient wolves in Asia than those in Europe, suggesting a domestication somewhere in the east

n international group of geneticists and archaeologists, led by the Francis Crick Institute, have found that the ancestry of dogs can be traced to at least two populations of ancient wolves. The work moves us a step closer to uncovering the mystery of where dogs underwent domestication, one of the biggest unanswered questions about human prehistory. 

Dogs are known to have originated from the gray wolf, with this domestication occurring during the Ice Age, at least 15,000 years ago. But where this happened, and if it occurred in one single location or in multiple places, is still unknown.

Previous studies using the archaeological record and comparing the DNA of dogs and modern wolves have not found the answer.

In their study, published in Nature today (29 June), the researchers turned to ancient wolf genomes to further understanding of where the first dogs evolved from wolves. They analysed 72 ancient wolf genomes, spanning the last 100,000 years, from Europe, Siberia and North America.

The remains came from previously excavated ancient wolves, with archaeologists from 38 institutions in 16 different countries contributing to the study. The remains included a full, perfectly preserved head from a Siberian wolf that lived 32,000 years ago. Nine different ancient DNA labs then collaborated on generating DNA sequence data from the wolves.

By analysing the genomes, the researchers found that both early and modern dogs are more genetically similar to ancient wolves in Asia than those in Europe, suggesting a domestication somewhere in the east.

However, they also found evidence that two separate populations of wolves contributed DNA to dogs. Early dogs from north-eastern Europe, Siberia and the Americas appear to have a single, shared origin from the eastern source. But early dogs from the Middle East, Africa and southern Europe appear to have some ancestry from another source related to wolves in the Middle East, in addition to the eastern source.

One possible explanation for this dual ancestry is that wolves underwent domestication more than once, with the different populations then mixing together. Another possibility is that domestication happened only once, and that the dual ancestry is due to these early dogs then mixing with wild wolves. It is not currently possible to determine which of these two scenarios occurred. 

Anders Bergström, co-first author and post-doctoral researcher in the Ancient Genomics lab at the Crick, says: “Through this project we have greatly increased the number of sequenced ancient wolf genomes, allowing us to create a detailed picture of wolf ancestry over time, including around the time of dog origins.”

“By trying to place the dog piece into this picture, we found that dogs derive ancestry from at least two separate wolf populations – an eastern source that contributed to all dogs and a separate more westerly source, that contributed to some dogs.”

The team are continuing the hunt for a close ancient wolf ancestor of dogs, which could reveal more precisely where domestication most likely took place. They are now focusing on genomes from other locations not included in this study, including more southerly regions.

As the 72 ancient wolf genomes spanned around 30,000 generations, it was possible to look back and build a timeline of how wolf DNA has changed, tracing natural selection in action.

For example, they observed that over a period of around 10,000 years, one gene variant went from being very rare to being present in every wolf, and is still present in all wolves and dogs today. The variant affects a gene, IFT88, which is involved in the development of bones in the skull and jaw. It is possible that the spread of this variant could have been driven by a change in the types of prey available during the Ice Age, giving an advantage to wolves with a certain head shape, but the gene could also have other unknown functions in wolves.

Pontus Skoglund, senior author and group leader of the Ancient Genomics lab at the Crick, says: “This is the first time scientists have directly tracked natural selection in a large animal over a time-scale of 100,000 years, seeing evolution play out in real time rather than trying to reconstruct it from DNA today.”

“We found several cases where mutations spread to the whole wolf species, which was possible because the species was highly connected over large distances. This connectivity is perhaps a reason why wolves managed to survive the Ice Age while many other large carnivores vanished.”

"Similar whole-genome time series from the Ice Age, in humans or other animals, could provide new information about how evolution happens."

Underwater jars reveal Roman period winemaking practices


From the amphorae to understanding the content; this multi-analytical analysis relied on archaeobotany and molecular identification. 

IMAGE: FROM THE AMPHORAE TO UNDERSTANDING THE CONTENT; THIS MULTI-ANALYTICAL ANALYSIS RELIED ON ARCHAEOBOTANY AND MOLECULAR IDENTIFICATION. view more 

CREDIT: LOUISE CHASSOUANT, CC-BY 4.0 (HTTPS://CREATIVECOMMONS.ORG/LICENSES/BY/4.0/)

Winemaking practices in coastal Italy during the Roman period involved using native grapes for making wine in jars waterproofed with imported tar pitch, according to a study published June 29, 2022 in the open-access journal PLOS ONE by Louise Chassouant of Avignon University and colleagues.

The authors examined three Roman period amphorae – wine jars – from a seabed deposit near the modern harbor of San Felice Circeo, Italy, about 90 km southeast of Rome. A combination of chemical markers, plant tissue residue, and pollen provided evidence of grape derivatives and pine within the jars. The evidence suggests the amphorae were used in both red and white winemaking processes, while the pine was used to create tar for waterproofing the jars and perhaps also flavoring the wine, as has been observed at similar archaeological sites.

The grapevine pollen matches wild species from the area, suggesting these winemakers were using local plants, although it remains unclear whether these were domesticated at the time. The pine tar, on the other hand, is non-local, and was likely imported from Calabria or Sicily based on other historical sources.

The authors emphasize the benefit of this multidisciplinary approach to characterize cultural practices from archaeological artefacts. In this case, the identification of plant remains, chemical analysis, historical and archaeological records, amphorae design, and previous findings all contributed to the conclusions of this analysis, providing an example of methodology for interpreting a history beyond the artefacts which would not be possible using a single technique.

The authors add: “If there was a message to be retained from the reading of this article, it would be related to the multidisciplinary methodology to be applied. Indeed, by using different approaches to unravel the content and nature of the coating layer of Roman amphorae, we have pushed the conclusion further in the understanding of ancient practices than it would have been with a single approach.”

The freely available article in PLOS ONE: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0267129