Tel Aviv University researchers were able to reconstruct the diet of Stone Age people. In an article published in the Yearbook of the American Physical Anthropology Association, Dr. Miki Ben-Dor and Prof. Ran Barkai of the Jacob M. Alkov Department of Archeology at Tel Aviv University, along with Raphael Sirtoli from Portugal, have seen it as an apex predator for about two million years. Only the extinction of larger animals (megafauna) in various parts of the world, and the decline of animal food sources towards the end of the Stone Age, led people to gradually increase the vegetable element in their diet, until they finally had no other choice. then had to tame both plants and animals – and became farmers.
“So far, attempts to reconstruct the diet of Stone Age people have been based mainly on comparisons with 20th century hunter-gatherer societies,” explains Dr. Ben-Dor explains. “This comparison is meaningless, however, because two million years ago hunter-gatherer societies were able to hunt and consume elephants and other large animals – while today’s hunter-gatherers have no access to such bounties. The whole ecosystem has changed and the conditions are not. We decided to use other methods to reconstruct the diet of Stone Age people: to examine the memory preserved in our own body, our metabolism, genetics and physical structure. fast, but evolution is slow. The body remembers. “
In an unprecedented trial in its scale, Dr. Ben-Dor and his colleagues gathered about 25 lines of evidence from about 400 scientific papers from various scientific disciplines, addressing the central question: Were Stone Age humans specialized carnivores or generalist omnivores? ? Most of the evidence was found in research on current biology, namely genetics, metabolism, physiology and morphology.
“A prominent example is the acidity of the human stomach,” says Dr. Ben-Dor. “The acidity in our stomach is high compared to omnivores and even other predators. Producing and maintaining strong acidity requires large amounts of energy, and its existence is evidence for consuming animal products. Strong acidity provides protection. against harmful bacteria found in meat, and prehistoric humans, who hunted large animals whose meat lasted for days or even weeks, often ate aged meat that contained large amounts of bacteria and was thus necessary to maintain high acidity. indication that they are predators is the structure of the fat cells in our body. In the bodies of omnivores, fat is stored in a relatively small number of large fat cells, while in predators, including humans, it is the other way around: we have a much greater number of smaller ones. fat cells Significant evidence for the evolution of humans as predators has also been found in our genome. Geneticists, for example, have co It was concluded that parts of the human genome were closed to a diet rich in fat, while in chimpanzees parts of the genome were opened to allow for a high sugar diet. “
Evidence from human biology has been supplemented by archaeological evidence. For example, research on stable isotopes in the bones of prehistoric humans, as well as hunting practices unique to humans, show that humans specialize in hunting large and medium-sized animals with high fat content. Comparing humans to large social predators of today, all of which hunt large animals and derive more than 70% of their energy from animal sources, reinforced the conclusion that humans specialized in hunting large animals and were, in fact, hypercarnivores.
“Hunting large animals is not an afternoon hobby,” says Dr. Ben-Dor. “It requires a lot of knowledge, and lions and hyenas achieve these skills after years of learning. It is clear that the remains of large animals found in numerous archaeological sites are the result of the high expertise of humans as hunters of large animals. Many researchers studying the extinction of the large animals agree that human hunting played a significant role in this extinction – and there is no better evidence of humans’ specialization in hunting large animals. activity throughout most of human evolution. Other archaeological evidence – such as the fact that specialized tools for obtaining and processing plant food did not appear until the later stages of human evolution – also support the central role of large animals in human life. diet, throughout most of human history. “
The multidisciplinary reconstruction carried out by TAU researchers for nearly a decade proposes a complete paradigm shift in understanding human evolution. Contrary to the widespread hypothesis that humans owe their evolution and survival to their dietary flexibility, which allowed them to combine animal hunting with plant foods, the picture emerging here is that humans usually evolve as predators of large animals.
“Archaeological evidence does not ignore the fact that Stone Age people also consumed plants,” adds Dr. Ben-Dor. “But according to the findings of this study, plants did not become an important part of the human diet until the end of the era.”
Evidence of genetic changes and the appearance of unique stone tools for processing plants led the researchers to conclude that, starting about 85,000 years ago in Africa, and about 40,000 years ago in Europe and Asia, there was a gradual rise in plant food consumption. as well as nutritional diversity – in accordance with different ecological conditions. This rise was accompanied by an increase in the local uniqueness of the stone tool culture, which is comparable to the diversity of material cultures in 20th century hunter-gatherer societies. In contrast, over the two million years that humans were apex predators, according to the researchers, long periods of similarity and continuity were observed in stone tools, regardless of local ecological conditions.
“Our study deals with a very large current controversy – both scientific and non-scientific,” said Prof. Barkai. “For many people, the Paleolithic diet is a critical issue today, not only with regard to the past, but also with regard to the present and the future. It is difficult to convince a devout vegetarian that his / her ancestors have no were vegetarians, and humans tend to confuse personal beliefs with scientific reality. Our study is both multidisciplinary and interdisciplinary. We propose a picture unmatched in its inclusiveness and breadth, clearly showing that humans were initially apex predators, specializing in hunting large animals. As Darwin discovered, the adaptation of species to obtaining and digesting their food is the main source of evolutionary change, and therefore the claim that humans were apex predators during most of their development can be broadly based. provide fundamental insights about the biological and cultural e evolution of man. ”
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