Yesterday I asked the question What emotion should precede action? and considered the idea that all emotions have an evolutionary driving force on the inherited genes because those emotions generated successful actions on average. The idea behind that thought was that it was the adult’s problems that created the emotional expressions, and that is where the driving force was exerted.
Perhaps the primary driving force is not the adult’s successful emotional responses but the infant’s. Before an infant develops the ability to speak, its only forms of purposeful communication with its mother are gross physical expressions and facial expressions.
Of course, the man in the photos above will influence the conversations with his interlocutors and that will be important, and those expressions will be used all of his adult life. But the infant’s facial expressions are a matter of life or death. If the infant fails to create an intimate bond with its caregiver and clearly communicate its needs, it will receive little or no care. If that is valid, then the driving force for the evolution of facial expressions of emotions is with the infant. If it doesn’t succeed in communicating well, it will perish and thus will not give its genetic codes to the future.
With that clarified, it becomes a legitimate question to ask, what emotions do the various infant expressions generate in a caregiver? One of the most compelling actions to a mother is a soulful crying of her baby. That seems obvious, and yet the facial expression of distress is not in Paul Ekman’s basic list of facial emotions. The closest expression would be sadness or fear, but either doesn’t seem as compelling of motherly action as crying out in distress. Sadness and fear are too passive and anger too generalized.
Stated boldly –
The infant must get proper attention with its communications or it will die and thus not leave its genes in the gene pool of human behavior. We are the living result of the infant’s successful communication.