According to researchers at the University of Utah, the bones of the human face have evolved to be more robust for protection against repeated impacts by small objects like the human fist, which they claim similarly evolved to protect the hand’s delicate musculoskeletal system when punching.
David Carrier, co-author of “Protective buttressing of the hominin face,” said in a statement that, “[i]f indeed the evolution of our hand proportions were associated with selection for fighting behavior you might expect the primary target, the face, to have undergone evolution to better protect it from injury when punched.”
“When modern humans fight hand-to-hand the face is usually the primary target,” he continued. “What we found was that the bones that suffer the highest rates of fracture in fights are the same parts of the skull that exhibited the greatest increase in robusticity during the evolution of basal hominins.”
Carrier and his co-author, Michael Morgan, contend that these changes to the facial feature appear at the same time as human ancestors evolved a hand with proportions capable of forming a fist. According to Carrier, “[t]he australopiths were characterized by a suite of traits that may have improved fighting ability, including hand proportions that allow formation of a fist; effectively turning the delicate musculoskeletal system of the hand into a club effective for striking.”
Together, these findings suggest “that many of the facial features that characterize early hominins may have evolved to protect the face from injury during fighting with fists.”
The implications of the pair’s conclusions reach outside debates about human evolution. “The debate over whether or not there is a dark side to human nature goes back to the French philosopher Rousseau who argued that before civilization humans were noble savages; that civilization actually corrupted humans and made us more violent,” Carrier said.
His work with Morgan would indicate otherwise. “What our research has been showing is that many of the anatomical characters of great apes and our ancestors, the early hominins — such as bipedal posture, the proportions of our hands and the shape of our faces — do, in fact, improve fighting performance,” he said.
He and Morgan were careful to stress that this does mean that humans are “naturally” or “inherently” violent, only that they evolved in an environment in which a particular mode of violence manifested itself.
[“Australopithecus africanus – Cast of Taung child” by Didier Descouens, Creative Commons Licensed]