Yes, you are a unique snowflake, remarkably different from all the other people around you -- or at least your face is, anyway.
Humans have the most diverse faces of any animal on Earth, and that's because it was an evolutionary advantage for early humans to look unique and recognizable.
One thing that sets humans apart from most animals: we get an astonishing number of social cues from reading each other's faces. Researchers have done studies on micro-expressions, momentary facial movements that last only a fraction of a second and convey a wide range of emotions. We can tell a lot about what a person is feeling by studying their face, while most other animals use sound or scent to communicate.
"Humans are phenomenally good at recognizing faces; there is a part of the brain specialized for that," Michael J. Sheehan said. Sheehan is one of the authors of this study. "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."
The study was published on Sept. 16 online in the journal Nature Communications.
The social structure of early people influenced the way we look, the new study proposes. There is more variation possible in genes for human faces than in most other species of animals. From the shape of our noses to the space between our features, there is a wide range possible for human faces. The researchers behind this new study said that this is not due to mere chance; humans evolved with this capacity for facial uniqueness because it was advantageous to our societies to be able to socialize visually.
The researchers looked at DNA and found that there was a wider range of variability possible for facial genes than for other body parts, like the length of your hand. They also found that more facial genes are independent of each other than genes for other body parts. The example they used is that if someone has long arms, they likely also have long legs. However, having a larger mouth does not mean larger eyes, for example.
Michael Nachman, another co-author, called this variability subtle, but consistent and statistically significant.
The team culled their data from an army database from 1988, consisting of men and women. They found that there was more variety among faces of African Americans and European Americans than in other parts of the body, like height. The most varied region they found was the eyes, mouth and nose.
