What did the Swiss eat during the Bronze Age?

The Bronze Age (2200 to 800 BC) was a decisive step in the technological and economic development of ancient societies. People living at the time faced a series of challenges: changes in the climate, opening up trade, and some population growth. How did they respond to changes in their diet, especially in Western Switzerland? A team from the University of Geneva (UNIGE), Switzerland, and Pompeu Fabra University (UPF) in Spain has performed isotope analyzes on human and animal skeletons along with plant remains for the first time. The scientists found that over time the use of manure had become widespread to improve yields in response to demographic growth. The researchers also found that a radical change in diet had taken place after the introduction of new grains, such as millet. In fact, the spread of millet reflected the need to embrace new crops after the drought that ravaged Europe during this period. Finally, the team showed that the resources used were mainly terrestrial. The research results are published in the journal PLOS ONE.

Today, the archaeological resources for studying the Bronze Age are limited. “This is partly due to changes in funeral rites,” said Mireille David-Elbiali, an archaeologist at the Laboratory of Prehistoric Archeology and Anthropology at F.-A. Trout Department in UNIGE’s Faculty of Science. “People were gradually abandoning the inhumation practice in favor of cremation, drastically reducing the bone material needed for research. And yet the Bronze Age marks the beginning of today’s societies with the rise of metallurgy.” As the name suggests, societies began to work with bronze, an alloy composed of copper and tin. “And this development in metallurgy called for more intensive trade so that they could obtain the essential raw materials. This increased the circulation of traditional crafts, prestigious goods, religious concepts and of course people between Europe and China,” the archaeologist continues.

Diet pressed into bones

The Neolithic marked the beginning of animal husbandry and the cultivation of wheat and barley. But what about the diet in the next Bronze Age? Archeobotany and archeozoology have been routinely used to reconstruct the Bronze Age diet, environment, agricultural practices, and ranching, but these methods only provide general information. “For the first time, we decided to accurately answer this question by directly analyzing human and animal skeletons. This meant that we could study the stable isotopes of the collagen of the bones and teeth that make up them and their living conditions. determine ”, continues Alessandra Varalli. , a researcher in the UPF Department of Human Sciences and the study’s lead author. “In fact, we are what we eat,” said Marie Besse, a professor at the Laboratory of Prehistoric Archeology and Anthropology at F.-A. Trout Department at UNIGE. Biochemical analyzes of bones and teeth will tell us what kinds of resources have been consumed. Forty-one human skeletons, 22 animal skeletons and 30 plant samples from locations in Western Switzerland and Haute-Savoie (France) were studied, ranging from the beginning to the end of the Bronze Age.

No differences between men, women and children

The first outcome of the study showed that there was no difference between the diet of men and women, and that there were no drastic changes in the diet between childhood and adulthood of these individuals. So there was no specific strategy for feeding children, just as men didn’t eat more meat or dairy than women. What’s more, when it comes to the origin of the proteins consumed, it was found that although Western Switzerland is home to a lake and rivers, the diet was mainly based on land animals and plants, excluding fish or other freshwater supplies, ”adds Dr. Varalli But the main importance of the research lies with plants, which reveal social unrest.

Agriculture adapted to climate change

“During the Early Bronze Age (2200 to 1500 BC), agriculture was mainly based on barley and wheat, two grains of Near Eastern origin that were cultivated in Europe from the Neolithic Age,” explains Dr. Varalli explains. “But from the late Late Bronze Age (1300 to 800 BC) we see millet being introduced, a plant from Asia that grows in a drier environment.” In addition, nitrogen isotopes showed that fertilization was used more intensively. “The analysis of different plant species from different phases of the Bronze Age suggests that there has been an increase in soil fertilization over time. This likely stimulated crop production.”

These two discoveries together seem to confirm the general drought that prevailed in Europe during this period, which meant that agriculture had to be adjusted; and that there was more trade between different cultures, such as northern Italy or the Danube region, which led to the introduction of millet in western Switzerland. These new cereals may have played an important role in security of supply and may have contributed to the population growth observed in the Late Bronze Age. These grains grow even faster and are more drought resistant, at a time when the climate was relatively warm and dry. Finally, the use of fertilizers went hand in hand with a general improvement in techniques, both agricultural and artisanal. “This first study of dietary changes in Western Switzerland during the Bronze Age confirms what we know about that period. But it also demonstrates the richness of the widespread cross-cultural exchanges,” says Professor Besse enthusiastically. We still have much to learn about this millennium, despite the scientific difficulties associated with the scarcity of available material. “This is one of the reasons why I excavated the Eremita Cave with UNIGE students. Located in the Piemonte region of Italy, it dates back to the Middle Bronze Age around 1600 BC,” concludes Professor Besse.