A popular theory holds that meat was essential for the growth of the human brain. New research shows otherwise.
Kent – Nearly two million years ago, a new species called Homo erectus appeared. In this species, the guts got smaller while the brains grew, research shows. Fossil finds in East Africa, dated to be around two million years old, show lacerations. These indicate that early humans hunted, slaughtered and ate their prey from this point at the latest, reports the SWR .
Based on this temporal parallel, it was hypothesized that meat consumption by Homo erectus had led to enormous growth of the brain. Andrew Barr explains: “One of the leading ideas is that if you switch from a plant-based diet to a high-protein, high-fat diet, meaning eating meat and bone marrow from carcasses, you have the energy needed to feed a larger brain.” Barr is a paleoanthropologist at George Washington University and studies the environment of early human evolution, according to the American magazine Popular Science .
“Meat made us human”: New findings cast doubt on the theory of brain evolution
This thesis, which is also referred to as the “meat made us human” hypothesis, has not yet been confirmed or disproved. A team of researchers from Kent State University in the US re-examined the fossil results and questioned the theory.
“We’re definitely seeing an increase in the number of bones marked for clipping,” says Briana Pobiner, a zooarchaeologist at the Smithsonian’s Museum of Natural History. She and Andrew Barr worked on the study, which was first published in the journal PNAS . “But we wanted to find out if this is a real behavioral signal. Or is it just that if you get more fossils out of the ground, you get more cut-marked fossils?”
Researchers challenge theory: Meat may not be critical to brain evolution
Together with the rest of the team, they returned to the fossil site in East Africa. They counted the number of fossils and bones that showed evidence of slaughter, reports Popular Science . To confirm the theory, researchers would need to find a higher proportion of butchered bones after the species Homo erectus appeared. However, that was not the case.
The results do not disprove the theory, but call it into question. To know for sure if human brain growth is related to meat consumption, more research needs to be done and other clues need to be looked for. In addition to this research, the human brain offers further research interests and open questions. (Fee Halberstadt)
