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What did Stone Age people eat before the advent of agriculture about 10,000 years ago? A long-standing stereotype – one that has influenced modern diets – is that ancient humans hunted large animals and feasted on mammoth steak.
But new research into a Paleolithic group called the Iberomaurusians, hunter-gatherers who buried their dead between 13,000 and 15,000 years ago in Taforalt Cave in what is now Morocco, adds to a growing body of evidence that challenges the idea that human ancestors relied primarily on meat. This is evident from a study published on Monday in the journal Nature Ecology & Evolution.
Scientists analyzed chemical signatures preserved in the bones and teeth of at least seven different Iberomaurusians and found that plants, not meat, were their main source of dietary protein.
“Our analysis showed that these hunter-gatherer groups included an important amount of plant material, wild plants, in their diet, changing our understanding of the diet of pre-agricultural populations,” said lead study author Zineb Moubtahij, a PhD candidate. at Géosciences Environnement Toulouse, a research institute in France, and the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.
The proportion of plant resources as a source of dietary protein among the people whose remains were studied was comparable to that of early farmers from the Levant, today’s eastern Mediterranean countries where plant domestication and agriculture were first discovered. documented.
Researchers also discovered a greater number of dental cavities in the Taforalt specimens than typically seen in hunter-gatherer remains from that period. The study shows that the Iberomaurus consumed “fermentable starchy plants,” such as wild grains or acorns, the study said. The findings raise some intriguing questions about how agriculture spread across different regions and populations.
“Although not all individuals obtained their proteins mainly from plants in Taforalt, it is unusual to document such a high proportion of plants in the diet of a pre-agricultural population,” said co-author Klervia Jaouen, a researcher at Géosciences Environnement Toulouse , in an email.
“This is probably the first time that such an important plant component in a Paleolithic diet has been documented using isotope techniques,” Jaouen added.
Deciphering ancient diets
The researchers used a technique called stable isotope analysis to learn more about the diet of each of the Iberomaurusians studied.
Nitrogen and zinc isotopes (variants of an element) in collagen and tooth enamel can reveal the amount of meat that used to be in the diet, while carbon isotopes can shed light on whether the main source of protein was meat or fish.
“People consume these foods and the isotope information is recorded in tissues such as bones and teeth,” Moubtahij said. “By analyzing the tissues we find in archaeological records, we can know whether someone ate more meat or more plant foods.”
The isotope technique shows the amount of plants eaten, but not the type. However, botanical remains of charred sweet acorns, pistachios, pine nuts, wild oats and legumes discovered at the site support the information gathered from the human remains. Grindstones excavated at the site also indicate that factory processing took place nearby.
The Iberomaurusians, however, were not strict vegetarians, the study noted. Cut marks on the remains of Barbary sheep and gazelles, as well as on ancient horse and cow mammals, suggested that some animals had been butchered and processed for food.
The increased reliance on plant-based foods was likely caused by several factors, including a wider range of edible plants and perhaps a depletion of large game species, the study said.
Directions for early weaning
The isotope analysis also found evidence of one case of early weaning, where starchy plant foods were introduced into a baby’s diet before it died between 6 and 12 months of age.
“This contrasts with hunter-gatherer societies where extended breastfeeding periods are the norm due to limited availability of weaning foods,” the study said.
The study only examined the eating habits of one group of Stone Age hunter-gatherers. However, a similar study published in January – which analyzed the remains of 24 early humans from two burial sites in Peru dating from 9,000 to 6,500 years ago – found that ancient diets in the Andes were composed of 80% plant material and 20% consisted of meat. .
A November 2022 study found that Neanderthals and early Homo sapiens were sophisticated cooks, combining botanicals such as wild nuts, peas, vetch, lentils and wild mustard.
“I don’t think there is a standard diet for everyone (during this period), but it depends on the environment. People are resilient and flexible in their dietary habits,” says Moubtahij.
The work undermines the idea that a Stone Age diet included a lot of meat – a rigid assumption perpetuated by contemporary dietary trends such as the Paleo diet. But the stereotype likely has its roots in previous research, and there are a few possible reasons why.
Evidence for eating meat, in the form of butchered animal bones, is often more “archaeologically visible” than the evidence for eating plants, says Briana Pobiner, a research scientist and museum lecturer in the Human Origins Program in the department of anthropology at the University of New York. York. Smithsonian National Museum of Natural History. She was not involved in the investigation.
Another reason for the idea that meat was central to early human diets is “the perception that hunting was a major behavioral innovation that occurred early in our evolutionary history – partly rooted in early hunter-gatherer studies conducted by male scientists who focused primarily on Male big game hunting was not documented, disregarded or downplayed by the important nutritional role of women who gathered smaller game and plant resources,” she said via email.
Revelations about the agricultural transition
Jaouen said archaeologists in the Levant region had documented a similar plant-based diet among another group that practiced a hunting-and-gathering lifestyle just before the development of agriculture, raising questions about why the transition to agriculture did not occur simultaneously among the Iberomaurus population.
“These findings indicate that several populations at the end of the Paleolithic adopted a diet similar in plant content to that of farmers,” she said.
The transition to agriculture was a complex process that happened at different times and at different rates, in different ways with different foods, in different places, Pobiner said.
“In other words, it was largely a local phenomenon that could entail transitional forms of existence – and not a single, sharp, simultaneous global shift,” she added.
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