As of today, there are 7.5 billion people living in the world, with each and every one having their unique facial structure. Why is that? What is the benefit and importance in that?
According to evolution the essence of life is to reproduce and survive.
In order to survive humans must have the ability to differentiate between a friend or a foe, stay protected from dangerous individuals, recognize who can be trusted, stay away from diseases and more.
This information allows us to see from whom to be protected and with whom to get close, you must be accessible, exposed and clear at any given moment. The human body evolved according to these requirements as the face contains the most information needed for survival. Face recognition is a primary and early evolutionary need, as seen in newborn babies who are particularly interested in human faces. They react to them immediately and especially to their mother who they depend on to survive.
A third of the human brain is wired to recognize faces. For example, the lower temporal lobe has an area called the Fusiform face Atea or FFA, which uniquely responds to faces. Also, there are neurons dedicated to certain people we know and are activated when we recognize them. As a result, Dr. Rodrigo Cian Quiroga of the University of Leicester in Britain called these neurons "Jennifer Aniston neurons."
But why does the brain dedicate so many resources into assigning large areas, cells, and neurons to recognize faces compared to other objects? This is because the face contains important and evolutionarily critical information. The face allows us to identify a person, to know whether we can rely on him, the face allows us to know the mood of the other, his gender, his age, his family closeness, his health, his parental suitability and even his developmental and genetic history.
Research shows a connection between facial structure and genetics.
For example, the PAX3 gene, which affects the structure and location of the nose, and mutations in the gene may develop into the warrensburg syndrome, which is well seen by the observer and suggests a genetic health problem.
Symmetry in the face shows the ability to cope with environmental data during development and the ability to cope with stressors and infections during development. People differ in their internal immune systems and their ability to maintain their steady development under environmental conditions.
Hormones also affect the appearance of face and body. Humans begin their lives as a female, but the amount of exposure to the hormone testosterone determines whether male or female affects the appearance of the face. Hormones also reflect clues about fertility and the availability of paired energy.
As science has shown, a structure and facial appearance is shaped by the individual biology and teaches about genetic quality, hormonal balance, health status and the information required to know how to deal with those who face it, to reproduce and survive for generations to come.
Reference
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