The concept of human uniqueness was once an exclusive problem for philosophy to solve, but as scientific knowledge continues to advance, we are learning more and more about the real explanations behind one of the most elusive problems in human evolution – why do humans look different from each other?
The human face is truly a unique system of body parts. Even identical twins do not share 100 percent of all their facial features; one would always have, say, a slightly yet unnoticeable longer nose than the other. Each human face is unique, and scientists have dedicated years of research to explain why.
According to Phys.org, scientists from the University of California, Berkeley are getting closer to the answer. UCB biologists have discovered why there is a far greater variation in facial structures among humans than other animals, including our closest cousins, chimpanzees and bonobos. Michael J. Sheehan, a behavioral ecologist and a postdoctoral fellow at UC Berkeley’s Museum of Vertebrate Zoology, says human faces evolved to be unique because of our highly visual social interactions.
While other animals employ the sense of smell, or use particular types of sounds to socialize with organisms within their genus, humans have been very keen to use our eyes to keep track of their ancient fellows. Because of our very visual preference for socialization, it wouldn’t be very advantageous for humans to share similar facial structures with each other. Through evolutionary means, populations over time have developed varied facial structures to maintain our knack for visually-reliant interactions.
“Humans are phenomenally good at recognizing faces; there is a part of the brain specialized for that. Our study now shows that humans have been selected to be unique and easily recognizable. It is clearly beneficial for me to recognize others, but also beneficial for me to be recognizable. Otherwise, we would all look more similar.”
Geneticist Michael Nachman, co-author of the latest study to reveal this intriguing discovery, says our social demands paved way for the evolution of varied human faces.
“The idea that social interaction may have facilitated or led to selection for us to be individually recognizable implies that human social structure has driven the evolution of how we look.”
The scientists discovered that the face is more varied from person to person than the rest of the body. This means that people can share the same torso or leg structure since they were not directly involved with visual interactions, but have faces different from each other because they were our primary tools for human communication. Although each individual human facial part, like the eye, followed a similar evolutionary track, the face as a whole may have arranged itself to become unique from each other to facilitate effective socialization among ancient humans.
The UC Berkeley study on the evolution of the uniqueness of the human face will be published in the online journal Nature Communications.
[Image from George A. Spiva Center for Arts/Flickr]