Tag: Archeology

Olive Trees Were First Domesticated 7,000 Years Ago

Earliest evidence for cultivation of a fruit tree, according to researchers.

A joint study by researchers from Tel Aviv University and the Hebrew University unraveled the earliest evidence for domestication of a fruit tree. The researchers analyzed remnants of charcoal from the Chalcolithic site of Tel Zaf in the Jordan Valley and determined that they came from olive trees. Since the olive did not grow naturally in the Jordan Valley, this means that the inhabitants planted the tree intentionally about 7,000 years ago. Some of the earliest stamps were also found at the site, and as a whole, the researchers say the findings indicate wealth, and early steps toward the formation of a complex multilevel society.

The groundbreaking study was led by Dr. Dafna Langgut of the The Jacob M. Alkow Department of Archaeology & Ancient Near Eastern Cultures, The Sonia & Marco Nadler Institute of Archaeology and the Steinhardt Museum of Natural History at Tel Aviv University. The charcoal remnants were found in the archaeological excavation directed by Prof. Yosef Garfinkel of the Institute of Archaeology at the Hebrew University. The findings were published in the journal Scientific Reports from the publishers of Nature.

‘Indisputable Proof of Domestication’

According to Dr. Langgut, Head of the Laboratory of Archaeobotany & Ancient Environments which specializes in microscopic identification of plant remains, “trees, even when burned down to charcoal, can be identified by their anatomic structure. Wood was the ‘plastic’ of the ancient world. It was used for construction, for making tools and furniture, and as a source of energy. That’s why identifying tree remnants found at archaeological sites, such as charcoal from hearths, is a key to understanding what kinds of trees grew in the natural environment at the time, and when humans began to cultivate fruit trees.”

In her lab, Dr. Langgut identified the charcoal from Tel Zaf as belonging to olive and fig trees. “Olive trees grow in the wild in the land of Israel, but they do not grow in the Jordan Valley,” she says. “This means that someone brought them there intentionally – took the knowledge and the plant itself to a place that is outside its natural habitat. In archaeobotany, this is considered indisputable proof of domestication, which means that we have here the earliest evidence of the olive’s domestication anywhere in the world.”

 

7,000 years-old microscopic remains of charred olive wood (Olea) recovered from Tel Tsaf (Photo: Dr. Dafna Langgut)

“I also identified many remnants of young fig branches. The fig tree did grow naturally in the Jordan Valley, but its branches had little value as either firewood or raw materials for tools or furniture, so people had no reason to gather large quantities and bring them to the village. Apparently, these fig branches resulted from pruning, a method still used today to increase the yield of fruit trees.”

Evidence of Luxury

The tree remnants examined by Dr. Langgut were collected by Prof. Yosef Garfinkel of the Hebrew University, who headed the dig at Tel Zaf. Prof. Garfinkel: “Tel Zaf was a large prehistoric village in the middle Jordan Valley south of Beit She’an, inhabited between 7,200 and 6,700 years ago. Large houses with courtyards were discovered at the site, each with several granaries for storing crops. Storage capacities were up to 20 times greater than any single family’s calorie consumption, so clearly these were caches for storing great wealth. The wealth of the village was manifested in the production of elaborate pottery, painted with remarkable skill. In addition, we found articles brought from afar: pottery of the Ubaid culture from Mesopotamia, obsidian from Anatolia, a copper awl from the Caucasus, and more.”

Dr. Langgut and Prof. Garfinkel were not surprised to discover that the inhabitants of Tel Zaf were the first in the world to intentionally grow olive and fig groves, since growing fruit trees is evidence of luxury, and this site is known to have been exceptionally wealthy.

Dr. Langgut: “The domestication of fruit trees is a process that takes many years, and therefore befits a society of plenty, rather than one that struggles to survive. Trees give fruit only 3-4 years after being planted. Since groves of fruit trees require a substantial initial investment, and then live on for a long time, they have great economic and social significance in terms of owning land and bequeathing it to future generations – procedures suggesting the beginnings of a complex society. Moreover, it’s quite possible that the residents of Tel Zaf traded in products derived from the fruit trees, such as olives, olive oil, and dried figs, which have a long shelf life. Such products may have enabled long-distance trade that led to the accumulation of material wealth, and possibly even taxation – initial steps in turning the locals into a society with a socio-economic hierarchy supported by an administrative system.”

Dr. Langgut concludes: “At the Tel Zaf archaeological site we found the first evidence in the world for the domestication of fruit trees, alongside some of the earliest stamps – suggesting the beginnings of administrative procedures. As a whole, the findings indicate wealth, and early steps toward the formation of a complex multilevel society, with the class of farmers supplemented by classes of clerks and merchants.”

Unravelling Recycling Practices from 500,000 Years Ago

The urge to collect in the prehistoric world: preserving memory of ancestors and connectedness with place and time.

What drove prehistoric humans to collect and recycle flint tools that had been made, used, and discarded by their predecessors? In a first-of-its-kind study at Tel Aviv University, researchers examined flint tools from one layer at the 500,000-year-old prehistoric site of Revadim in the south of Israel’s Coastal Plain, and propose a novel explanation: prehistoric humans, just like us, were collectors by nature and culture. The study suggests that they had an emotional urge to collect old human-made artefacts, mostly as a means for preserving the memory of their ancestors and maintaining their connectedness with place and time.

The study was led by PhD student Bar Efrati and Prof. Ran Barkai of the Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures at TAU’s The Lester and Sally Entin Faculty of Humanities, in collaboration with Dr. Flavia Venditti from the University of Tubingen in Germany and Prof. Stella Nunziante Cesaro from the Sapienza University of Rome, Italy. The paper appeared in the prestigious scientific journal Scientific Reports, published by Nature.

Prehistoric Vintage Tools

Bar Efrati explains that stone tools with two lifecycles have been found at prehistoric sites all over the world, but the phenomenon has never been thoroughly investigated. In the current study, the researchers focused on a specific layer at Revadim – a large, open-air, multi-layered site in the south of Israel’s Coastal Plain, dated to about 500,000 years ago. The rich findings at Revadim suggest that this was a popular spot in the prehistoric landscape, revisited over and over again by early humans drawn by an abundance of wildlife, including elephants. Moreover, the area is rich with good-quality flint, and most tools found at Revadim were in fact made of fresh flint. 

“The big question is: Why did they do it?” says Bar Efrati. “Why did prehistoric humans collect and recycle actual tools originally produced, used, and discarded by their predecessors, many years earlier? Scarcity of raw materials was clearly not the reason at Revadim, where good-quality flint is easy to come by. Nor was the motivation merely functional, since the recycled tools were neither unusual in form nor uniquely suitable for any specific use.”

Scars that Reveal the Past

The key to identifying the recycled tools and understanding their history is the patina – a chemical coating which forms on flint when it is exposed to the elements for a long period of time. Thus, a discarded flint tool that lay on the ground for decades or centuries accumulated an easily identifiable layer of patina, which is different in both color and texture from the scars of a second cycle of processing that exposed the original color and texture of flint.

In the current study, 49 flint tools with two lifecycles were examined. Produced and used in their first lifecycle, these tools were abandoned, and years later, after accumulating a layer of patina, they were collected, reworked, and used again. The individuals who recycled each tool removed the patina, exposing fresh flint, and shaped a new active edge. Both edges, the old and the new, were examined by the researchers under two kinds of microscopes, and via various chemical analyses, in search of use-wear marks and/or organic residues. In the case of 28 tools, use-wear marks were found on the old and/or new edges, and in 13 tools, organic residues were detected, evidence of contact with animal bones or fat.

Surprisingly, the tools had been used for very different purposes in their two lifecycles – the older edges primarily for cutting, and the newer edges for scraping (processing soft materials like leather and bone). Another baffling discovery: in their second lifecycle the tools were reshaped in a very specific and minimal manner, preserving the original form of the tool, including its patina, and only slightly modifying the active edge.

Recycled Tools as Keepsakes

Prof. Ran Barkai: “Based on our findings, we propose that prehistoric humans collected and recycled old tools because they attached significance to items made by their predecessors.”

“Imagine a prehistoric human walking through the landscape 500,000 years ago, when an old stone tool catches his eye. The tool means something to him – it carries the memory of his ancestors or evokes a connection to a certain place. He picks it up and weighs it in his hands. The artifact pleases him, so he decides to take it ‘home’. Understanding that daily use can preserve and even enhance the memory, he retouches the edge for his own use, but takes care not to alter the overall shape – in honor of the first manufacturer. In a modern analogy, the prehistoric human may be likened to a young farmer still plowing his fields with his great-grandfather’s rusty old tractor, replacing parts now and then, but preserving the good old machine as is, because it symbolizes his family’s bond with the land.”

“In fact,” says Barkai, “the more we study early humans, we learn to appreciate them, their intelligence, and their capabilities. Moreover, we discover that they were not so different from us. This study suggests that collectors and the urge to collect may be as old as humankind. Just like us, our early ancestors attached great importance to old artifacts, preserving them as significant memory objects – a bond with older worlds and important places in the landscape.”

Featured image: From Left to Right: Prof. Ran Barkai & Bar Efrati

Finding the Optimal Location for the Tribal Bonfire

Early humans’ placement of cave hearths ensured maximum benefit and minimum smoke exposure.

In a first-of-its kind study, the researchers developed a software-based smoke dispersal simulation model and applied it to a known prehistoric site. They discovered that the early humans who occupied the cave had placed their hearth at the optimal location – enabling maximum utilization of the fire for their activities and needs while exposing them to a minimal amount of smoke. The groundbreaking study provides evidence for high cognitive abilities in early humans who lived 170,000 years ago.

The study was led by PhD student Yafit Kedar, and Prof. Ran Barkai from the Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures at The Lester and Sally Entin Faculty of Humanities, together with Dr. Gil Kedar. The paper was published in Scientific Reports.

In the Back of the Cave? Or towards the front?

The use of fire by early humans has been widely debated by researchers for many years, regarding questions such as: At what point in their evolution did humans learn how to control fire and ignite it at will? When did they begin to use it on a daily basis? Did they use the inner space of the cave efficiently in relation to the fire? While all researchers agree that modern humans were capable of all these things, the dispute continues about the skills and abilities of earlier types of humans. One focal issue in the debate is the location of hearths in caves occupied by early humans for long periods of time.

“Multilayered hearths have been found in many caves, indicating that fires had been lit at the same spot over many years,” says Yafit Kedar. “In previous studies, using a software-based model of air circulation in caves, along with a simulator of smoke dispersal in a closed space, we found that the optimal location for minimal smoke exposure in the winter was at the back of the cave. The least favorable location was the cave’s entrance.”

Humans Need Balance

In the current study, the researchers applied their smoke dispersal model to an extensively studied prehistoric site – the Lazaret Cave in southeastern France, inhabited by early humans around 170-150 thousand years ago. “According to our model, based on previous studies, placing the hearth at the back of the cave would have reduced smoke density to a minimum, allowing the smoke to circulate out of the cave right next to the ceiling,” explains Kedar. “However, in the archaeological layers we examined, the hearth was located at the center of the cave.”

The team tried to understand why the occupants had chosen this spot, and whether smoke dispersal had been a significant consideration in the cave’s spatial division into activity areas. The researchers performed a range of smoke dispersal simulations for 16 hypothetical hearth locations inside the 290sqm cave. To understand the health implications of smoke exposure, measurements were compared with the average smoke exposure recommendations of the World Health Organization.

Excavations at the Lazaret Cave, France (photo: De Lumley, M. A. néandertalisation (pp. 664-p). CNRS éditions. (2018Les restes humains fossiles de la grotte du Lazaret. Nice, Alpes-Maritimes, France. Des Homo erectus européens évolués en voie de)

The researchers found that the average smoke density, based on measuring the number of particles per spatial unit, is in fact minimal when the hearth is located at the back of the cave – just as their model had predicted. However, Yafit Kedar and Dr. Gil Kedar explain that they also discovered that “In this situation, the area with low smoke density, most suitable for prolonged activity, is relatively distant from the hearth itself. Early humans needed a balance – a hearth close to which they could work, cook, eat, sleep, get together, warm themselves, etc. while exposed to a minimum amount of smoke. Ultimately, when all needs are taken into consideration – daily activities vs. the damages of smoke exposure – the occupants placed their hearth at the optimal spot in the cave.”

Our Ancestors Nailed It

The study identified a 25sqm area in the cave which would be optimal for locating the hearth in order to enjoy its benefits while avoiding too much exposure to smoke. Astonishingly, in the several strata examined in this study, the early humans actually did place their hearth within this area. 

“Our study shows that early humans were able, with no sensors or simulators, to choose the perfect location for their hearth and manage the cave’s space as early as 170,000 years ago – long before the advent of modern humans in Europe. This ability reflects ingenuity, experience, and planned action, as well as awareness of the health damage caused by smoke exposure. In addition, the simulation model we developed can assist archaeologists excavating new sites, enabling them to look for hearths and activity areas at their optimal locations,” concludes Prof. Barkai.

In upcoming studies, the researchers intend to use their model to investigate the influence of different fuels on smoke dispersal, use of the cave with an active hearth at different times of year, use of several hearths simultaneously, and more.

Start Up Nation in Ancient Canaan

Thanks to advanced management skills, the Arava became the copper power of the ancient world.

A new Tel Aviv University study has determined that thanks to advanced management methods and impressive technological creativity, about three thousand years ago, the Arava Valley’s [located deep in the Southern Negev desert in Israel, along the Jordanian border] copper industry managed to thrive and become the largest and most advanced smelting center in the ancient world. The study was conducted by graduate student David Luria of TAU’s Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures and The Sonia & Marco Nadler Institute of Archaeology, and is being published in the prestigious journal PLOS ONE.

Ancient Practice of “Trial and Error”

According to Luria, the copper industry in Canaan at that time was concentrated in two large mining areas – one in Timna (north of Eilat) and the other in Faynan (in the northern Arava, in Jordan). Previous research on the subject has claimed that the high level of technology employed there was made possible thanks to Egyptian technologies brought to the region during the voyage of the Egyptian Pharoah Shishak in 925 BC. This theory was strengthened in 2014 following the discovery of a scarab bearing the figure of Shishak in Faynan, and again later in 2019, following the development of a new scientific model that claimed that a sudden technological leap had taken place around the time of Shishak’s journey.

Luria, on the other hand, argues that the great economic and technological success of the copper industry in the Arava was not related to Egyptian capabilities, but rather to the talent of the Arava people, who learned to use the two advanced methods we know today as “trial and error” and “scaling up.” “Obviously these terms were not in use in ancient times, but the application of their practical principles was made possible due to a basic understanding of engineering and common sense, which were seen in other places in the ancient world as well,” says Luria.

Luria explains that the “trial and error” method allowed the Arava metalworkers to slowly improve technological processes, as well as to increase the volume and quality of production. In addition, “scaling up” made it possible to increase the dimensions of the existing means of production using materials and processes that were common at the time, thereby developing advanced production equipment within a short amount of time and with minimum cost and technological risk.

The Secret Behind the Technological Success

“Shishak’s expedition was not intended to physically take over the copper mines in the Arava, but rather to formulate a long-term agreement with the Arava people in order to bolster local production and thus increase copper exports to Egypt, which was suffering from local production difficulties at the time,” Luria says.

“It appears that the secret of the success of the ancient copper industry in the Arava lies in the skills and abilities of efficient managers, who were assisted at every stage of their decision-making by talented technological experts. Archeology today can’t identify who these executives were, but a careful analysis of the deposits left in the area can tell us an accurate story. These findings are the residues of copper production that have accumulated as heaps of waste that can be dated, and whose size allows us to assess the volume of production at any given time. Moreover, by conducting a chemical analysis of the copper content remaining in the waste, we can determine the quality of the production; when the amount of copper in the waste diminishes, we can conclude that the process had become more efficient.”

Luria also says that traces detected at these sites show that throughout the production period, the management team was able to close inefficient mines and open more efficient ones. Moreover, at certain points a decision was taken to reuse waste from earlier periods, which was produced in less efficient processes in which a lot of copper remained, rather than use the pure mineral. These decisions could not have been made without an excellent technical team that backed management decisions with regular technological testing. The management also engaged in extensive marketing of the copper throughout the ancient world.

“The important lesson to take away from this technological success is that the high-tech savvy of individuals – educated and energetic people who lived here in the first millennium BCE – succeeded, just like it does today, in bringing about a huge revolution in the local economy,” Luria concludes. “As they say, there is nothing new under the sun.”

Featured image: David Luria

Health Revelations from Ancient Jerusalem

Relic provides “window into the lives of people in ancient times”.

‘Who is wealthy?… Rabbi Yosef says: Anyone who has a bathroom close to his table.’ (The Talmud, Bavli Shabbat 25: 2).

Having a toilet was indeed an indicator of wealth in Jerusalem 2,700 years ago. The wealth was, however, no guarantee for good health, as a joint study by Tel Aviv University and the Israel Antiquities Authority (IAA) shows that even the wealthy residents of Jerusalem at that time suffered from diseases and epidemics. This became evident as an ancient toilet was uncovered in the garden of a luxury estate uncovered at the Armon Hanatziv Promenade in Jerusalem, and the researchers concluded that while the owners were undoubtable wealthy they also suffered from a range of intestinal parasites.

Rich, Yet in Poor Health

The study was led by Dr. Dafna Langgut of Tel Aviv University’s Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures, director of The Laboratory of Archaeobotany and Ancient Environments at The Sonia & Marco Nadler Institute of Archaeology and The Steinhardt Museum of Natural History. The research was published in the recent edition of the International Journal of Paleopathology.

Ya’akov Billig, who directed the excavation of the villa on behalf of the Israel Antiques Authority, dated the villa to the Late Iron Age of the 7th century BC. Aside from the toilet, magnificent stone artifacts of extraordinary workmanship were found at the site, such as decorated stone capitals of a quantity and quality never before observed in ancient Israel.

Langgut and Billig were not surprised by the recovery of a toilet in the garden of the estate, explaining that toilet facilities were extremely rare at that time and were a status symbol – a luxury facility that only the rich and high-ranking could afford.

Dr. Langgut collected sediment samples from underneath the stone toilet, chemically extracted the parasite eggs, scrutinized them under a light microscope, and identified them. The egg remains were discovered as part of a salvage excavation by the Israel Antiquities Authority, recently carried out at the Armon Hanatziv and funded by the Ir David Foundation. “The findings of this study are among the earliest observed in Israel to date,” she says. “These are durable eggs, and under the special conditions provided by the cesspit, they survived for nearly 2,700 years.”

She says the parasites that were found cause symptoms like abdominal pain, nausea, diarrhea, and itching. Some of them are especially dangerous for children and can lead to malnutrition, developmental delays, nervous system damage, and, in extreme cases, even death. 

 

Dr. Dafna Langgut at the Laboratory of Archaeobotany and Ancient Environments

Intestinal disease at the time, she explains may have been the result of either poor sanitary conditions, the use of human feces to fertilize field crops or the consumption of improperly cooked beef or pork. In the absence of medicine, its recovery was difficult to impossible, and those infected could suffer from the parasites for the rest of their lives. Therefore, it is quite possible that the findings of the study indicate a bothersome and long-lasting infectious that affected the entire population. Langgut points out that these parasites still exist today, but the modern Western world has developed effective diagnostic means and medications, so they don’t turn into an epidemic.  

The examination of the toilet samples came as Dr. Langgut was developing a new field of research called ‘archeoparasitology’, whereby researchers identify microscopic remains of intestinal worm eggs to learn about the history of diseases and epidemics. This area provides new information regarding human hygiene, lifestyle, and sanitary conditions.

“Studies like this one help us document the history of infectious diseases in our area and provide us with a window into the lives of people in ancient times,” Dr. Langgut concludes.

 

The excavation site at the Armon Hanatziv Promenade in the Jerusalem where the toilet was found (Photo: Yuli Schwartz, Israel Antiquities Authority)

Featured image: The stone toilet seat found during the 2019 excavation at Armon Hanatziv.

Over the Past 1.5 Million Years, Human Hunting Preferences have Wiped Out Large Animals

Breakthrough study tracks development of early humans’ hunting habits.

A groundbreaking study by researchers from Tel Aviv University tracks the development of humans’ hunting practices over the last 1.5 million years – as reflected in the animals we’ve hunted and consumed. The researchers believe that at any given time early humans preferred to hunt the largest animals available in their surroundings, which provided the greatest quantities of food in return for their effort.

In this way, according to the researchers, early humans repeatedly overhunted large animals to extinction and then went on to the next in size – while improving their hunting technologies to meet the new challenge. The researchers also claim that about 10,000 years ago, when animals larger than deer became extinct, humans began to domesticate plants and animals to supply their needs, which might explain why the agricultural revolution began in the Levant at precisely that time.

The study was conducted by Prof. Ran Barkai and Dr. Miki Ben-Dor of The Jacob M. Alkow Department of Archaeology and Ancient Near Eastern Cultures, Prof. Shai Meiri of the School of Zoology and The Steinhardt Museum of Natural History, and Jacob Dembitzer, a research student of Prof. Barkai and Prof. Meiri, who led the project. The paper was published in the prestigious scientific journal Quaternary Science Reviews.

The study, unprecedented in both scope and timespan, presents a comprehensive analysis of data on animal bones discovered at dozens of prehistoric sites in and around Israel. Findings indicate a continual decline in the size of game hunted by humans as their main food source – from giant elephants 1-1.5 million years ago down to gazelles 10,000 years ago. According to the researchers, these findings paint an illuminating picture of the interaction between humans and the animals around them over the last 1.5 million years.

Overhunting or Climate Changes?

Prof. Barkai notes two major issues presently addressed by prehistorians worldwide: What caused the mass extinction of large animals over the past hundreds of thousands of years – overhunting by humans or perhaps recurring climate changes? And what were the driving forces behind great changes in humankind – both physical and cultural – throughout its evolution?

Prof. Barkai: “In light of previous studies, our team proposed an original hypothesis that links the two questions: We think that large animals went extinct due to overhunting by humans, and that the change in diet and the need to hunt progressively smaller animals may have propelled the changes in humankind. In this study we tested our hypotheses in light of data from excavations in the Southern Levant covering several human species over a period of 1.5 million years.”

Prof. Ran Barkai

Jacob Dembitzer adds: “We considered the Southern Levant (Israel, the Palestinian Authority, Southwest Syria, Jordan, and Lebanon) to be an ‘archaeological laboratory’ due to the density and continuity of prehistoric findings covering such a long period of time over a relatively small area – a unique database unavailable anywhere else in the world. Excavations, which began 150 years ago, have produced evidence for the presence of humans, beginning with Homo erectus who arrived 1.5 million years ago, through the Neanderthals who lived here from an unknown time until they disappeared about 45,000 years ago, to modern humans (namely, ourselves) who came from Africa in several waves, starting around 180,000 years ago.”

The researchers collected all data available in the literature on animal bones found at prehistoric sites in the Southern Levant, mostly in Israel. These excavations, conducted from 1932 until today, provide a unique sequence of findings from different types of humans over a period of 1.5 million years. With some sites comprising several stratigraphic layers, sometimes thousands of years apart, the study covered a total of 133 layers from 58 prehistoric sites, in which thousands of bones belonging to 83 animal species had been identified. Based on these remains, the researchers calculated the weighted mean size of the animals in each layer at every site.

Prof. Meiri: “Our study tracked changes at a much higher resolution over a considerably longer period of time compared to previous research. The results were illuminating: we found a continual, and very significant, decline in the size of animals hunted by humans over 1.5 million years. For example, a third of the bones left behind by Homo erectus at sites dated to about a million years ago, belonged to elephants that weighed up to 13 tons (more than twice the weight of the modern African elephant) and provided humans with 90% of their food. The mean weight of all animals hunted by humans at that time was 3 tons, and elephant bones were found at nearly all sites up to 500,000 years ago.”

“Starting about 400,000 years ago, the humans who lived in our region – early ancestors of the Neandertals and Homo sapiens, appear to have hunted mainly deer, along with some larger animals weighing almost a ton, such as wild cattle and horses. Finally, in sites inhabited by modern humans, from about 50,000 to 10,000 years ago, approximately 70% of the bones belong to gazelles – an animal that weighs no more than 20-30kg. Other remains found at these later sites came mostly from fallow deer (about 20%), as well as smaller animals such as hares and turtles.”

Climate Change had Minimal Impact

Jacob Dembitzer: “Our next question was: What caused the disappearance of the large animals? A widely accepted theory attributes the extinction of large species to climate changes through the ages. To test this, we collected climatic and environmental data for the entire period, covering more than a dozen cycles of glacial and interglacial periods. This data included temperatures based on levels of the oxygen 18 isotope, and rainfall and vegetation evidenced by values of carbon 13 from the local Soreq Cave. A range of statistical analyses correlating between animal size and climate, precipitation, and environment, revealed that climate, and climate change, had little, if any, impact on animal extinction.”

According to Dr. Ben-Dor: “Our findings enable us to propose a fascinating hypothesis on the development of humankind: Humans always preferred to hunt the largest animals available in their environment, until these became very rare or extinct, forcing the prehistoric hunters to seek the next in size. As a result, to obtain the same amount of food, every human species appearing in the Southern Levant was compelled to hunt smaller animals than its predecessor, and consequently had to develop more advanced and effective technologies. Thus, for example, while spears were sufficient for Homo erectus to kill elephants at close range, modern humans developed the bow and arrow to kill fast-running gazelles from a distance.”

Environmental Damage from the Dawn of Humanity

Prof. Barkai concludes: “We believe that our model is relevant to human cultures everywhere. Moreover, for the first time, we argue that the driving force behind the constant improvement in human technology is the continual decline in the size of game. Ultimately, it may well be that 10,000 years ago in the Southern Levant, animals became too small or too rare to provide humans with sufficient food, and this could be related to the advent of agriculture. In addition, we confirmed the hypothesis that the extinction of large animals was caused by humans – who time and time again destroyed their own livelihood through overhunting. We may therefore conclude that humans have always ravaged their environment but were usually clever enough to find solutions for the problems they had created – from the bow and arrow to the agricultural revolution. The environment, however, always paid a devastating price.”

Featured image: Prof. Shai Meiri of the School of Zoology and The Steinhardt Museum of Natural History

Ancient Climate Crisis Transformed Us from Nomadic Hunters to Settled Farmers

Researchers used plant remains to reconstruct the climate in the Southern Levant at the end of the last ice age.

What made the residents in the Southern Levant, tens of thousands of years ago, put down their walking sticks and hunting gear and instead become settled farmers? Apparently, it was the result of a climate crisis that took place at the end of the last ice age, about 10,000 to 20,000 years ago.

A new record of significant climate changes in the region, based on the identification of ancient plant remains, sheds light on the dramatic transition. Against the background of the Glasgow Climate Change Summit, the researchers believe that understanding the response of the region’s flora to the dramatic past climate changes can help in preserving the regional variety of plant species and in planning for current and future climate challenges.

The Crisis that Marched Humanity Forward

The research was conducted by Dr. Dafna Langgut of the Department of Archaeology and The Steinhardt Museum of Natural History at Tel Aviv University; Prof. Gonen Sharon, Head of the MA Program in Galilee Studies at Tel-Hai College, and Dr. Rachid Cheddadi, expert in evolution and palaeoecology of University of Montpellier, Institute of Evolutionary Sciences (ISEM) Montpellier, France. The groundbreaking study was recently published in the leading scientific journal Quaternary Science Reviews.

The study was conducted at the prehistoric archaeological site Jordan River Dureijat (“Jordan River Stairs”) on the shores of the ancient Lake Hula. The site is unique for its exceptional preservation conditions yielding finds that enabled discovery of the primary activity of its early local residents – fishing. Preserved botanic remains also enabled researchers to identify the plants that grew 10,000 – 20,000 years ago in the Hula Valley and its surroundings. 

 

The prehistoric archaeological site Jordan River Dureijat (“Jordan River Stairs”) on the shores of the Paleo Lake Hula

Two major processes in world history took place during this period, the first of which was the transition from a nomadic to a settled lifestyle that occurs during a period of dramatic climate change. Prof. Sharon, supervisor of the Madregot Hayarden (“Jordan Stairs”) excavation, explains: “In the study of prehistory, this period is called the Epipalaeolithic period. At its outset, people were organized in small groups of hunter-gatherers who roamed the area. Then, about 15,000 years ago, we are witness to a significant change in lifestyle: the appearance of settled life in villages, and additional dramatic processes that reach their apex during the Neolithic period that followed. This is the time when the most dramatic change of human history occurred – the transition to the agricultural way of life that shaped the world as we know it today.”

Dr. Langgut, an archaeobotanist specializing in identification of plant remains, elaborates on the second dramatic process of this period, namely the climatic changes that occurred in the region. “Although at the peak of the last ice age, about 20,000 years ago, the Mediterranean Levant was not covered with an ice sheet as in other parts of the world, the climatic conditions that existed nevertheless differed from those of today. Their exact characteristics were unclear until this study. The climatic model that we built is based on reconstruction of the fluctuation of the spread of plant species indicating that the main climatic change in our area is expressed by a drop in temperature (up to five degrees Celsius less than today), whereas the precipitation amounts (rain, snow, sleet, or hail) were close to those of today (only about 50 mm less than today’s annual average).

 

Dr. Dafna Langgut

Temperature Fluctuations

However, Dr. Langgut explains that about 5,000 years later, in the Epipalaeolithic period (about 15,000 years ago) a significant improvement in climate conditions can be seen in the model. An increased prevalence of heat-tolerant tree species, such as olive, common oak, and Pistacia, indicate an increase in temperature and precipitation.

During this period, the first sites of the Natufian culture appear in our region. It could very well be that the temperate climate assisted in the development and flourishing of this culture, in which permanent settlement, stone structures, food storage facilities, and more first appear on the global stage.  

The next stage of the study deals with the end of the Epipalaeolithic period, about 11,000-12,000 years ago, known globally as the Younger Dryas period. This period is characterized by a return to a cold, dry climate like that of the ice age, causing somewhat of a climate crisis around the world. The researchers claim that until this study, it was unclear whether and to what extent there was any expression of this period in the Levantine region.

Little Rain, but Throughout the Year

According to the researchers: “The findings that arise from the climate model presented in the article show that the period was characterized by climatic instability, intense fluctuations, and a considerable drop in temperatures. Nevertheless, while reconstructing the precipitation, a surprising phenomenon was discovered: the average quantities of rainfall reconstructed were only slightly less than those of today; however, the precipitation was distributed over the entire year, including summer rains.”

The researchers claim that such distribution assisted in the expansion and thriving of annual and leafy plant species. The gatherers who lived in this period now had a wide, readily available variety of gatherable plants throughout the entire year. This variety enabled their familiarity just before domestication. The researchers are of the opinion that these findings contribute to a new understanding of the environmental changes that took place on the eve of the transition to agriculture and domestication of animals.

Summary

Why did humans settle down and start farming the land? While this study doesn’t fully answer this questions, it does reconstruct the climate in what is today Israel from 20,000 to 10,000 years ago, revealing the dramatic environmental and climatic changes that uniquely combined with social and technological innovations 12,000 years ago and formed the background for the development of acriculture in the Levant. 

The warmer, more humid climate between 15,000 and 13,000 years ago coincided with the Natufian culture, and may have supported their practice of living in one place for a long time, thanks to increased gathering and storage opportunities. Around 13,000 years ago, temperatures sunk a bit and rains would fall throughout the year, favoring open-field vegetation and plants. 12,000 years ago, the Holocene (the current geological era) began, which in the Near East meant long hot and dry summers necessitating gathering and storing food during winter and spring. The new environmental conditions pushed people to make greater efforts to domesticate, farm and store their crops – setting the stage for the Neolithic revolution. 

Dr. Langgut concludes: “This study contributes not only to understanding the environmental background for momentous processes in human history such as the first permanent settlement and the transition to agriculture, but also provides information on the history of the region’s flora and its response to past climatic changes. There is no doubt that this knowledge can assist in preserving species variety and in meeting current and future climate challenges.”

 

Dr. Dafna Langgut collects sediment samples for pollen investigation.

Featured image: An Israeli farmer in his vineyard