What are kisses for? Why do we like them so much?

Evolutionary keys to understand kissing.

It is well known that the vast majority of human beings kiss, have kissed or will kiss someone at some point in their lives. These curious rituals are surprising for how much they occur and for the many meanings they may hold. There are kisses that serve to reconcile, but they can also denote affection, attraction or even politeness.

However, none of this changes the fact that kissing, by itself, seems a rather absurd act. Why does it seem so natural for us to approach another person and brush our lips against them? What are kisses for?

What are kisses for, and what is their real use?

Finding an answer to this requires, first of all, to dig in our pastto see what is the basis of this custom. Some evolutionary psychologists believe that kissing is an act to which we are genetically predisposed and whose utility is basic to the perpetuation of the species. Therefore, to ask what kissing is for is also to ask how it has helped us to survive.

In this regard, many researchers have pointed out the importance of kissing in the resolution of two basic problems: finding a mate y bonding with other people.

A wise choice in the search for a partner

The first of these functions has to do with our unconscious sensitivity to analyze chemical signals coming from the potential partner's body. Smell plays a part in this task, but the sense of taste also serves a similar purpose.

Detecting chemical patterns in the other person's saliva is useful when it comes to knowing the general state of their body, their hormone levels and the characteristics of their immune system. In short, kisses are a way to indirectly know the health status of the person who has approached us of the person who has approached us, to know to what extent their immune system complements ours, and from there unconsciously decide if they could be a good reproductive partner.

Strengthening bonds

The second function is the easiest to digest, because most kisses can be understood as a protocol for bonding with someone. However, this process has an unconscious aspect that goes beyond the symbolic charge associated with this custom. It has been observed that kissing produces an increase in the secretion of oxytocin and endorphins, substances associated with bonding and the elimination of tension.

In addition, the neurotransmitters serotonin and dopamine, which are associated with infatuation and addiction addictionare also triggered during the kiss, which, if we add the above cocktail of hormones, can contribute to what is known as romantic love. The person with whom the kiss has been shared suddenly becomes more important.

If we add to this the fact that the kiss could be of use in choosing a mate, it seems evident that its functions are focused towards the reproduction and breeding.

Our species could be predisposed towards kisses on the mouth because of its evolutionary legacy, as these have also been observed in other animals (bonobos, for example). Cultureculture, however, would have been creating varieties of kisses and modeling the form in which they are presented, appearing alternatives to the kiss on the mouth that, however, are perhaps variants indebted to the latter type.

Why do we like kissing?

Clearly, no one decides to kiss someone to get information about that person, or even to bond with that person. Kisses are there because we like them.. Evolution has caused the main utility of these practices, which is located in the long term, to be masked by a short-term objective: to obtain pleasure.

This pleasure is based on the large number of sensory neurons in the tongue and lips. These areas show one of the highest densities of such cells, and are therefore extremely sensitive to potentially pleasurable stimuli.

Thus, a few seconds of kissing generates an important torrent of information that goes directly to the brain.The brain is the most sensitive to this kind of stimuli, so that most of the mental processes start to revolve around this experience. It is then when the substances we have mentioned begin to be massively secreted and the neurotransmitters related to pleasure and falling in love take center stage. Hence, a good kiss can make you lose track of time: the whole body is paying close attention to what is happening in this interaction.

NOTE: If you want to know more about what kissing is for, you might be interested in the book The Science of Kissing.