Early human hunter-gatherers ate mostly plants and vegetables, according to archeological findings that undermine the commonly held view that our ancestors lived on a high protein, meat-heavy diet.
The evidence, from the remains of 24 individuals from two burial sites in the Peruvian Andes dating to between 9,000 and 6,500 years ago, suggests that wild potatoes and other root vegetables may have been a dominant source of nutrition before the shift to an agricultural lifestyle.
“Conventional wisdom holds that early human economies focused on hunting – an idea that has led to a number of high-protein dietary fads such as the paleo diet,” said Dr Randy Haas, an archeologist at the University of Wyoming and senior author of the paper. “Our analysis shows that the diets were composed of 80% plant matter and 20% meat.”
Some have previously suggested that the shift to agricultural economies was driven by over-hunting, but the latest findings raise the possibility of a more gradual transition from foraging to farming.
The study focused on remains taken from the Wilamaya Patjxa and Soro Mik’aya Patjxa burial sites, which are about a mile apart in the Andes mountains. The scientists analysed the bones, comparing the chemical forms of carbon and nitrogen with those found in local plants and animals. The analysis suggested that plant foods comprised the majority of the individuals’ diets, with meat playing a secondary role.
“Food is incredibly important and crucial for survival, especially in high-altitude environments like the Andes,” said Jennifer Chen, a PhD student in anthropology at Penn State University and first author of the paper, published in the journal PLOS One. “A lot of archaeological frameworks on hunter-gatherers, or foragers, centre on hunting and meat-heavy diets, but we are finding that early hunter-gatherers in the Andes were mostly eating plant foods like wild tubers.”
The researchers also found evidence of burnt plant remains from the sites and distinct patterns of dental-wear on the upper incisors of several individuals that indicate tubers, possibly wild potatoes, were the most prominent food source.
The analysis also indicated that large mammals, such as deer or llamas, made up most of the meat in the diet, rather than smaller mammals, birds or fish.
Haas said the view that early humans ate mostly meat was widespread in archeological circles. “If you were to talk to me before this study I would’ve guessed meat comprised 80% of the diet,” he said. “It is a fairly widespread assumption that human diets were dominated by meat.”
This view was partly driven by the archeological record, which is biased towards evidence of meat-eating because stone tools and butchered animal bones are much more likely to be preserved than plant remains.
The biases of mostly male archeologists from western cultures, in which hunting is viewed as a masculine pursuit, is also likely to have played into perpetuating a “macho caveman” stereotype of early human society, according to Haas, who added that similar biases may have coloured research into early human diet in other regions of the world.
