Russia (bbabo.net), - In modern science, the idea of the decisive role of meat in the development of the brain of the ancestors of Homo sapiens has become established. A new study published in the journal PNAS casts doubt on this hypothesis.
About two million years ago, our ancestors made a big leap in development. They had a large body and a large brain - thanks to their developed mental abilities, they began to use the first tools and, along with Homo erectus, were the first human species to leave Africa.
But what was the defining impetus for the development of early Homo? One of the leading hypotheses of anthropologists says: the reason is a change in diet. Protein food is more nutritious than vegetable food - this made it possible to nourish the brain and made it possible for it to grow. According to scientists, the ability to make fire and cook food on it provided the brain with the necessary burst of energy: such food is easier to digest than raw food, and this may be the reason why Homo erectus had a large brain.
And archaeological finds seem to support the popular hypothesis that "meat made us human": Animal bones have often been found at Homo erectus sites. "Generations of paleoanthropologists have explored places like the famous Olduvai Gorge in northern Tanzania and found evidence that early humans ate meat," said lead author Andrew Barr, an anthropologist at George Washington University in the US.
The problem, however, is that the found fossils of our ancestors are very few and "unevenly distributed in space and time."
Thus, Barr's team wondered if there was enough fossil evidence known to date to support a change in eating habits.
To test this, the researchers examined published data from nine major areas in East Africa, including 59 sites dated between 2.6 and 1.2 million years ago.
The analysis showed that the total number of animal bones and other evidence of predation about two million years ago are associated not so much with the meat-eating of our ancestors, but with "the increased attention of researchers to this period of time." For example, the period from 2.6 to 1.9 million years ago is very poorly represented - there is little fossil evidence for the existence of hominins and their diet during this period. Much more finds from the subsequent phase.
"When you quantify the data, as we did to test the 'meat made us human' hypothesis, it starts to fall apart," says Barr. Because at the time of Homo erectus, there was no increase in evidence of predation.
“I have been studying artifacts such as footprints on animal bones from various locations for more than 20 years, but the current results of the study of pores came as a big surprise to me,” says co-author Briana Pobiner from the National Museum of Natural History at the Smithsonian Institution (USA). "The study changes our understanding of what zooarchaeological finds can reveal about prehistoric meat-eating."
According to the research team, the results of their work show that the evidence underlying the hypothesis about the role of meat-eating in human evolution is statistically incorrect. New data, say Barr and his colleagues, speaks against this hypothesis.
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