Researchers at Tel Aviv University have been able to reconstruct the nutrition of people from the Stone Age. In a paper published in the Yearbook of the American Association of Physical Anthropology, Dr. Miki Ben-Dor and Prof. Ran Barkai of the Department of Archeology Jacob M. Alkov at Tel Aviv University, together with Raphael Sirtoli of Portugal, show that humans were a peak predator of about two million years. Only the disappearance of larger animals (megafauna) in different parts of the world and the decline of animal food sources towards the end of the Stone Age, led people to gradually grow the plant element in their diet, until they finally had no choice but to domesticate. both plants and animals – and became a farmer.
“To date, attempts to reconstruct the diet of the Stone Age people have been largely based on comparisons with twentieth-century hunter-gatherer societies,” explains Dr. Ben-Dor. “This comparison is in vain, however, because two million years ago hunter-gatherer societies could hunt and consume elephants and other large animals – while today’s hunter-gatherers do not have access to such a reward. The entire ecosystem has changed. and conditions can not be compared We decided to use other methods to reconstruct the diet of people in the Stone Age: to examine the memory stored in our own bodies, metabolism, genetics and our physical construction.Human behavior changes rapidly, but evolution is slow. he remembers. “
In an unprecedented process, Dr. Ben-Dor and his colleagues collected about 25 lines of evidence from about 400 scientific papers from various scientific disciplines that address the main question: People in the Stone Age were carnivores. specialized or were they generalist omnivores? Most evidence has been 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. The production and maintenance of strong acidity requires large amounts of energy, and its existence is evidence of consumption of animal products. Strong acidity provides protection against harmful bacteria found in meat , and prehistoric people, hunting large animals whose meat was sufficient for days or even weeks, often ate old meat that contained large amounts of bacteria and therefore had to maintain a high level of acidity. Being predatory is the structure of fat cells in 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 larger number of smaller fat cells Significant evidence for the evolution of humans as predators has also been found in our genome. the conclusion that “areas of the human genome were closed to allow a t-rich diet, while in chimpanzees, areas of the genome were opened to allow a high-sugar diet. “
Evidence from human biology has been supplemented by archaeological evidence. For example, research on the isotopes established in the bones of prehistoric humans, as well as the unique hunting practices of humans, shows that humans have specialized in hunting large and medium-sized animals with a high fat content. Comparing humans with the great social predators of today, all hunting large animals and obtaining more than 70% of their energy from animal sources, strengthened 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 takes a lot of knowledge, and lions and hyenas reach these skills after many years of learning. Clearly, the remains of large animals found in countless archaeological sites are the result of high human expertise as large animal hunters. Many researchers studying extinction of large animals agree that hunting by humans has played a major role in this extinction – and there is no better evidence of the specialization of humans in hunting large animals.Most likely, as with predators today, hunting in itself was another archaeological evidence – such as the fact that specialized tools for obtaining and processing plant foods appeared only in the later stages of human evolution – also supports the centrality of large animals in the human diet, for most of human history . “
The multidisciplinary reconstruction carried out by TAU researchers for almost 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 food flexibility, which has allowed them to combine animal hunting with plant food, the image here is of humans evolving mostly as predators of large animals.
“Archaeological evidence does not overlook the fact that people in the Stone Age also consumed plants,” adds Dr. Ben-Dor. “But according to the findings of this study, plants became a major component of the human diet only towards the end of the era.”
Evidence of genetic change and the emergence of unique stone tools for plant processing have led researchers to conclude that since about 85,000 years ago in Africa and about 40,000 years ago in Europe and Asia, there has been an increase. gradual consumption of plant foods as well as food diversity – according to various ecological conditions. This growth has been accompanied by an increase in the local uniqueness of the culture of stone instruments, which is similar to the diversity of material cultures in the hunter-gatherer societies of the twentieth century. Instead, in the two million years when, according to researchers, humans were apex predators, long periods of similarity and continuity were observed in stone tools, regardless of local ecological conditions.
“Our study addresses a very current controversy – both scientific and non-scientific,” says Prof. Barkai. “For many people today, the Paleolithic diet is a critical issue, not only in terms of the past, but also in terms of the present and the future. It is difficult to convince a devoted vegetarian that his ancestors were not vegetarians, and people tend to confuse personal beliefs with scientific reality. Our study is both multidisciplinary and interdisciplinary. We propose an unprecedented image by inclusion and width, which clearly shows that humans were originally apex predators, who specialized in hunting large animals. As Darwin discovered, adapting species to obtain and digest their food is the main source of evolutionary change, and therefore the claim that humans have been apex predators throughout their development can provide a broad basis for fundamental knowledge of biological and cultural evolution. of people. ”
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