Paleo diet? The study reveals new insight into what Stone Age humans actually ate CNN

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What did Stone Age people eat before the advent of agriculture about 10,000 years ago? A long-standing stereotype that influenced modern fad diets is that ancient humans hunted large animals and ate mammoth steaks.

But new research into a Paleolithic group called the Iberomaurus, hunter-gatherers who buried their dead in Taforalt Cave in modern-day Morocco between 13,000 and 15,000 years ago, adds to a growing body of evidence that challenge the notion that human ancestors were primarily meat-based. , according to a study published Monday in the journal Nature Ecology & Evolution.

The scientists analyzed chemical signatures preserved in bones and teeth belonging to at least seven different Iberomaurus and found that plants, not meat, were their primary source of dietary protein.

Our analysis showed that these hunter-gatherer groups included a significant amount of plant matter, wild plants in their diet, which changed our understanding of the diet of pre-agricultural populations, said the lead study author Zineb Moubtahij, PhD student. at Gosciences Environnement Toulouse, a research institute in France, and at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany.

The proportion of plant resources as a source of dietary protein in the humans whose remains were studied was similar to that observed in the early farmers of the Levant, the present-day eastern Mediterranean countries where domestication and ‘plant agriculture.

The researchers also detected a greater number of dental cavities among the Taforalt specimens than is typically seen with hunter-gatherer remains from that period. Evidence suggests that Iberomaurus consumed fermentable starchy plants such as wild grains or acorns, the study found. The findings raise some intriguing questions about how agriculture spread across different regions and populations.

Although not all individuals primarily obtained their protein 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, researcher at Gosciences Environnement Toulouse , in an email.

This is probably the first time that such a significant plant component in a Paleolithic diet has been documented using isotope techniques, Jaouen added.

The researchers used a technique called stable isotope analysis to learn about the diet of each of the iberomaurus studied.

Isotopes of nitrogen and zinc (variants of an element) contained in collagen and tooth enamel can reveal how much meat was in ancient diets, while isotopes of carbon can clarify whether the main source of protein was meat or fish.

Humans consume these foods, and the isotope information is recorded in tissues such as bones and teeth, Moubtahij said. By analyzing these tissues that we find in the archaeological record, we can tell if a person ate more meat or ate more plant-based foods.

The isotope technique shows the amount of plants eaten but not the type. However, the botanical remains of charred acorns, pistachios, pine nuts, wild oats and legumes discovered at the site support the information obtained from the human remains. Grindstones discovered at the site also suggest that plant processing took place nearby.

However, Iberomaurus were not strict vegetarians, the study noted. Cut marks on the remains of Barbary sheep and gazelles, as well as ancient horse- and cow-like mammals, suggested that some animals had been slaughtered and processed for food.

According to the study, the increased reliance on plant foods was likely driven by several factors, including a wider range of edible plants and perhaps a depletion of large game species.

Isotope analysis also detected evidence of early weaning, with starchy plant foods introduced into the infants’ diets before they died between 6 and 12 months of age.

This is in contrast to hunter-gatherer societies where extended lactation periods are the norm due to the limited availability of weaning food, the study found.

The research only looked at diets among a group of Stone Age hunter-gatherers. However, a similar study published in January that analyzed the remains of 24 early humans from two burial sites in Peru dating from 9,000 to 6,500 years ago revealed that ancient diets in the Andes were composed of 80% vegetable matter and 20% meat.

A November 2022 study revealed that Neanderthals and early Homo sapiens were sophisticated cooks, combining plant ingredients such as nuts, peas, vetch, lentils and wild mustard.

I don’t think there is a standard diet for everyone (in this period), but it depends on the environment. Humans are resilient and flexible in their dietary habits, Moubtahij said.

The work undermines the idea that a Stone Age diet was heavy on meat, a rigid assumption perpetuated by current dietary trends like the Paleo diet. But the stereotype likely has its roots in earlier research, and there are a few possible reasons.

Evidence for meat-eating, in the form of unearthed animal bones, is often more visible archaeologically than evidence for plant-eating, said Briana Pobiner, a research scientist and museum educator in the anthropology department’s Human Origins Program. from the Smithsonian National. Museum of Natural History. She did not participate in the study.

Another reason for the idea that meat was central to early human diets is the perception that hunting was a key behavioral innovation that occurred early in our evolutionary history rooted in part in early hunter-gatherer studies. readers made by male scholars who focused primarily on big game. he said by email.

Jaouen said that in the Levant region, archaeologists had documented a similar plant-based diet among another group that practiced a hunting and gathering lifestyle just before the development of agriculture, and raised questions about why the transition to agriculture did not occur simultaneously among the Iberomaurusian population.

These findings indicate that several populations in the late Paleolithic adopted a diet similar in plant content to that of farmers, he said.

The transition to agriculture was a complex process that occurred at different times and proceeded 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 involve transient forms of livelihoods, not a single, abrupt, simultaneous global change, he added.