A joint study by researchers of the Weizmann Institute and the Israel Antiquities Authority, which examined fava seeds exposed in archaeological excavations in recent years at Neolithic sites in the Galilee, sheds light on the nutritional habits of the people that lived in the area 10,000 years ago. Seeds found at the prehistoric sites show that the inhabitants’ diet at the time consisted mainly of fava beans, as well as lentils, various types of peas and chickpeas.
The study was conducted by archaeobotanist Valentina Caracuta, of the Weizmann Institute, together with Dr. Elisabetta Boaretto and Dr. Lior Regev, and in cooperation with archaeologists Dr. Kobi Vardi, Dr. Yitzhak Paz, Dr. Hamoudi Khalaily, Dr. Ianir Milevski and Dr. Omri Barzilai of the Israel Antiquities Authority.
The multitude of fava seeds found at the Neolithic sites excavated in the Galilee during the past few years indicates the preference placed on growing fava beans. The dating of the seeds, which was done at the Kimmel Center in the Weizmann Institute, indicated a range of dates between 9,890–10,160 YBP. These well-preserved seeds were found in excavations, inside storage pits (granaries) after they had been husked. The seeds’ dimensions are a uniform size–a datum showing they were methodically cultivated, and were harvested at the same period of time, when the legumes had ripened. According to the researchers, keeping the seeds in storage pits is also reflective of long-term agricultural planning, whereby the stored seeds were intended not only for food, but also to ensure future crops in the coming years.
The researchers added, “The identification of the places where plant species that are today an integral part of our diet were first domesticated is of great significance to research. Despite the importance of cereals in nutrition that continues to this day, it seems that in the region we examined (west of the Jordan River), it was the legumes, full of flavor and protein, which were actually the first species to be domesticated. A phenomenon known as the agricultural revolution took place throughout the region at this time: different species of animals and plants were domesticated across the Levant, and it is now clear that the area that is today the Galilee was the main producer of legumes in prehistoric times. This is a process that lasted thousands of years, during which certain characteristics of wild species changed, and domesticated plant species were created. To this day, most of the chickpeas grown in the country are cultivated in the Galilee region”.
According to the archaeologists, the accurate dating of the fava seeds, utilizing advanced techniques, led to the conclusion that they found the world’s oldest domesticated fava seeds, dating to 10,125–10,200 YBP.
Stone tools, cooked animal and plant remains and fire pits found at the Monte Verde site in southern Chile provide greater interdisciplinary evidence that the earliest known Americans--a nomadic people adapted to a cold, ice-age environment--were established deep in South America more than 15,000 years ago. The research, led by Tom Dillehay, Rebecca Webb Wilson University Distinguished Professor of Anthropology, appears in the Nov. 18 issue of PLOS ONE.
A very small faceted basalt wedge. Basalt is a local material. This tool, also found at MVI, was made 15,000-16,000 years ago. It would have been used for woodworking.
(Courtesy Tom Dillehay)
In 2013, at the request of Chile's National Council of Monuments, Dillehay and an international team of archaeologists, geologists and botanists performed an archaeological and geological survey of Monte Verde to better define the depth and breadth of the site, which is protected by the Chilean government.
It's familiar ground for Dillehay, who has worked there since 1977, and it's there that Dillehay found evidence that fundamentally contributed to a new understanding of how and when humans first arrived in the Americas.
Until about 40 years ago, the prevailing understanding was that the Americas first began to be populated 13,000 years ago by big-game hunters from Asia who used a distinctive type of fluted stone projectile point called Clovis points. Dillehay's work at Monte Verde, however, has yielded a wide variety of scientific evidence of a small human settlement using a different stone tool technology that predated the Clovis people by about 1,500 years at a site called MVII. He also uncovered possible, though not conclusive, evidence of a much earlier human presence at a nearby site called MVI. Subsequent excavations at sites in both North and South America have also yielded evidence supporting this earlier human migration through the Americas.
On this visit, Dillehay's team explored key areas around MVI and MVII. Though it was not intended to be a comprehensive reexamination of the site, their findings did yield new insights. "We began to find what appeared to be small features--little heating pits, cooking pits associated with burned and unburned bone, and some stone tools scattered very widely across an area about 500 meters long by about 30 or 40 meters wide," said Dillehay.
The stone tools discovered by the team were similar to what Dillehay had previously found at Monte Verde. Many were simple unifacial tools--meaning they were worked on only one side of the stone, to create a sharp edge--though some of the younger tools and projectile points indicate bifacial technologies. "One of the curious things about it that is that unlike what we found before, a significant percentage, about 34 percent, were from non-local materials. Most of them probably come from the coast but some of them probably come from the Andes and maybe even the other side of the Andes," said Dillehay. Prior research had revealed evidence of Andean plants in the area, providing further support for a highly mobile population.
Stones, bones, plants and fires
The team recovered a total of 39 stone objects and 12 small fire pits associated with bones and some edible plant remains, including nuts and grasses. The bones tended to be small fragments, broken and scorched, indicating that the animals had been cooked. They often came from very large animals, like prehistoric llamas or mastodons, as well as smaller creatures like prehistoric deer and horses. The Monte Verde site was unlikely to have been able to support the kind of vegetation that those animals needed to eat, so they were likely killed and butchered elsewhere. The objects were radiocarbon dated and most were found to range in age from more than 14,000 to almost 19,000 years old.
The wide scattering suggests that the people who created these features were nomadic hunter-gatherers who might have camped for only a night or two before moving on. "Where they're going, we don't know, and where they're coming from, we don't know, but this would have been a passageway from the coast to the foothills of the Andes," Dillehay said. Dillehay believes that they may have come through Monte Verde because the terrain was more walkable than the surrounding bogs and wetlands, and because it provided access to stone to make tools.
Rain, ice, soil and ash
A key goal during this visit was to better understand the geological and environmental context of the site. At the end of the last ice age, Monte Verde was a sandur plain--a runoff area situated about six kilometers away from a glacier, crisscrossed by a network of shallow streams and brooks fed by rain washing off the glacier, as well as melting snow. It was also a time marked by volcanic activity and a gradually warming climate, as the last glaciers began to retreat.
"It appears that these people were there in the summer months," Dillehay said. "Each one of these [burned] features and the bones and stones associated with them is embedded in thin, oxidized tephra"--a type of geological layer formed by airborne ash particles from nearby volcanoes that only form in rainy, warmer temperatures. But though the glaciers had begun to retreat by 19,000 to 17,000 years ago, it was still an extremely challenging environment, Dillehay said. "We're looking at people living in some really cold, harsh areas, even in the summer months." Only later, around 15,000 years ago, did the climate warm enough to support the kind of longer-term settlement found at MVII.
Put together, these findings support the paradigm shift toward an earlier peopling of the Americas, although questions inevitably remain about how the hemisphere was settled. It also underscores the importance of long-term interdisciplinary research. "We now realize that the geology and the climate and the archaeology are much more complex than we ever calculated," said Dillehay.
The first sequencing of ancient genomes extracted from human remains that date back to the Late Upper Palaeolithic period over 13,000 years ago has revealed a previously unknown "fourth strand" of ancient European ancestry.
This new lineage stems from populations of hunter-gatherers that split from western hunter-gatherers shortly after the 'out of Africa' expansion some 45,000 years ago and went on to settle in the Caucasus region, where southern Russia meets Georgia today.
Here these hunter-gatherers largely remained for millennia, becoming increasingly isolated as the Ice Age culminated in the last 'Glacial Maximum' some 25,000 years ago, which they weathered in the relative shelter of the Caucasus mountains until eventual thawing allowed movement and brought them into contact with other populations, likely from further east.
This led to a genetic mixture that resulted in the Yamnaya culture: horse-borne Steppe herders that swept into Western Europe around 5,000 years ago, arguably heralding the start of the Bronze Age and bringing with them metallurgy and animal herding skills, along with the Caucasus hunter-gatherer strand of ancestral DNA - now present in almost all populations from the European continent.
The research was conducted by an international team led by scientists from Cambridge University, Trinity College Dublin and University College Dublin. The findings are published today in the journal Nature Communications.
"The question of where the Yamnaya come from has been something of a mystery up to now," said one of the lead senior authors Dr Andrea Manica, from Cambridge's Department of Zoology.
"We can now answer that as we've found that their genetic make-up is a mix of Eastern European hunter-gatherers and a population from this pocket of Caucasus hunter-gatherers who weathered much of the last Ice Age in apparent isolation. This Caucasus pocket is the fourth major strand of ancient European ancestry, one that we were unaware of until now," he said
Professor Daniel Bradley, leader of the Trinity team, said: "This is a major new piece in the human ancestry jigsaw, the influence of which is now present within almost all populations from the European continent and many beyond."
Previously, ancient Eurasian genomes had revealed three ancestral populations that contributed to contemporary Europeans in varying degrees, says Manica.
Following the 'out of Africa' expansion, some hunter-gatherer populations migrated north-west, eventually colonising much of Europe from Spain to Hungary, while other populations settled around the eastern Mediterranean and Levant, where they would develop agriculture around 10,000 years ago. These early farmers then expanded into and colonised Europe.
Finally, at the start of the Bronze Age around 5,000 years ago, there was a wave of migration from central Eurasia into Western Europe - the Yamnaya.
However, the sequencing of ancient DNA recovered from two separate burials in Western Georgia - one over 13,000 years old, the other almost 10,000 years old - has enabled scientists to reveal that the Yamnaya owed half their ancestry to previously unknown and genetically distinct hunter-gatherer sources: the fourth strand.
By reading the DNA, the researchers were able to show that the lineage of this fourth Caucasus hunter-gatherer strand diverged from the western hunter-gatherers just after the expansion of anatomically modern humans into Europe from Africa.
The Caucasus hunter-gatherer genome showed a continued mixture with the ancestors of the early farmers in the Levant area, which Manica says makes sense given the relative proximity. This ends, however, around 25,000 years ago - just before the time of the last glacial maximum, or peak Ice Age.
At this point, Caucasus hunter-gatherer populations shrink as the genes homogenise, a sign of breeding between those with increasingly similar DNA. This doesn't change for thousands of years as these populations remain in apparent isolation in the shelter of the mountains - possibly cut off from other major ancestral populations for as long as 15,000 years - until migrations began again as the Glacial Maximum recedes, and the Yamnaya culture ultimately emerges.
"We knew that the Yamnaya had this big genetic component that we couldn't place, and we can now see it was this ancient lineage hiding in the Caucasus during the last Ice Age," said Manica.
While the Caucasus hunter-gatherer ancestry would eventually be carried west by the Yamnaya, the researchers found it also had a significant influence further east. A similar population must have migrated into South Asia at some point, says Eppie Jones, a PhD student from Trinity College who is the first author of the paper.
"India is a complete mix of Asian and European genetic components. The Caucasus hunter-gatherer ancestry is the best match we've found for the European genetic component found right across modern Indian populations," Jones said. Researchers say this strand of ancestry may have flowed into the region with the bringers of Indo-Aryan languages.
The widespread nature of the Caucasus hunter-gatherer ancestry following its long isolation makes sense geographically, says Professor Ron Pinhasi, a lead senior author from University College Dublin. "The Caucasus region sits almost at a crossroads of the Eurasian landmass, with arguably the most sensible migration routes both west and east in the vicinity."
He added: "The sequencing of genomes from this key region will have a major impact on the fields of palaeogeneomics and human evolution in Eurasia, as it bridges a major geographic gap in our knowledge."
David Lordkipanidze, Director of the Georgian National Museum and co-author of the paper, said: "This is the first sequence from Georgia - I am sure soon we will get more palaeogenetic information from our rich collections of fossils."