Prehistoric Burial Site Reveals Surprising Secrets of Hunter–Gatherer Diet

A prehistoric burial site has yielded surprising insights into the diet of hunter-gatherers living thousands of years ago in Northwest Africa.

Researchers have found that a group of these hunter-gatherers ate predominantly plant-based foods, several millennia before agriculture arrived in the region, a study published in the journal Nature Ecology and Evolution reports.

The findings challenge the prevailing notion of a high-reliance on animal proteins among pre-agricultural human groups, as well as conventional models for the origin of agriculture, according to the authors.

For the study, a team led by Zineb Moubtahij of the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany, analyzed human and animal remains from the large Late Stone Age (LSA) cave burial site of Taforalt in present-day Morocco. The site, associated with a group of hunter-gatherers known as the Iberomaurusians, preserves remains dating to between roughly 15,000 and 13,000 years ago.

"In recent years, there has been a noticeable surge in interest in understanding the diets of our ancestors, often referred to as the 'paleo diet,'" Moubtahij told Newsweek. "This growing curiosity stems from a desire to explore how their dietary habits influenced their health and, in turn, how these ancient diets continue to impact our health in modern societies today.

"The change from hunting and gathering to farming was a big deal in history, and it probably changed what people ate and how healthy they were. However, there remains a gap in our knowledge regarding the diet transition from hunter-gatherers to farmers in Northwest Africa. So, our research aims to fill in this missing piece of the puzzle. By examining animal bone remains and the tools used for food processing and cooking, we can piece together clues about ancient diets."

The Iberomarusians were a prehistoric hunter-gatherer culture who lived in Northwest Africa (in the region that today stretches from Morocco to western Libya) between around 25,000 and 11,000 years ago. This period predates the emergence of agriculture in the region, which arrived from the Near East around 7,600 years ago.

In the Near East, one of the most important regions for the development of agriculture, hunter-gatherers from the Natufian culture—dated to around 14,000 to 11,000 years ago—exploited wild plants to such an extent that they began to cultivate, and eventually domesticate, them.

By contrast, it was traditionally not thought that the Iberomaurusians in North Africa—who appear to have been genetically related to the Natufians—exploited wild plants to any great extent. But the latest results indicate that their diet was, in fact, heavily reliant on plant foods.

The team came to this conclusion after conducting what is known as an "isotopic analysis"—a technique that can reveal the proportions of meat, fish and plants in the diets of prehistoric peoples. This approach involves analyzing stable isotopes, which are atoms of a given element with the same number of protons but a different quantity of neutrons. These occur in different ratios in different organisms.

"Stable isotopes are like fingerprints—each food type has an isotopic fingerprint," Moubtahij said. "Humans consume food, ingesting its isotopic information, which is then recorded in our bones and teeth. Researchers analyze human bones and teeth found in archaeological records and can estimate their diet. A person who ate more plants would have different isotopic information than a person who ate more meat."

This approach revealed that while the Iberomaurusians buried at Taforalt did eat some animal proteins, their diet predominantly consisted of wild plants, of which they consumed a "substantial" quantity, according to Moubtahij. The remains of acorns, pine nuts and wild pulses found at the Taforalt site further support this notion.

"Surprisingly, our findings indicate minimal evidence of seafood or freshwater food consumption among these ancient populations," Moubtahij said.

Additionally, the results of the study suggest that these human groups may have incorporated wild plants into the diets of their infants at an earlier stage than previously believed.

"Many people used to think that eating lots of plant-based food started only after agriculture began. But our study changes that idea," Moubtahij said. "This suggests that the switch to eating more plants might have started earlier than we thought, even before farming. Understanding this helps us see how our diets changed over time and how early humans adapted to their environment."

"I believe that ancient hunter-gatherers adapted differently to various habitats. Some have consumed more meat, some more fish, and some have included more plants," Moubtahij said. "The Mediterranean environment, known for its rich biodiversity of plant species, likely played a crucial role in shaping the dietary habits of these ancient humans. The abundance and variety of edible plants in this region may have drawn them to incorporate more plant foods into their diets."

Intriguingly, the significant reliance on plant foods at Taforalt did not appear to result in the development of plant cultivation, as occurred in the Near East with the Natufians. According to the authors, this suggests that wild plant exploitation does not necessarily lead to agriculture in all situations. The researchers suggest that the plants the Iberomaurusians ate may have been stored year-round to ensure consistent food supplies, perhaps enabling a degree of sedentism—the practice of living in one place for extended periods of time.

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