Emotions, not logic, help us choose a partner for sex and life. A person, no matter how he explains his preferences, still acts on the principle of "like — dislike".
Physiologist Vyacheslav Dubynin told in an interview with Yulia Menshova how the brain makes a choice, what role ancient genetic programs play in our decisions and how much society influences the behavior of each of us. "Lifehacker" made a summary of the conversation.
A person cannot continue the race alone, so he needs a partner. It is important to choose the right person for this role. Evolution has shown that it is not necessary to look too similar — most likely, this is a relative, and there will be no healthy offspring with him. But the one who is too different will not work either. It's probably an enemy, so it's best to stay away from it.
Nature and human society have created three main criteria for choosing a partner.
Each of us has our own personal label — a unique molecular passport. It is created by MHC molecules — in Russian, this abbreviation stands for "the main histocompatibility complex". These are proteins that are in every cell of our body. The effectiveness of the immune system depends on them — the ability to distinguish safe microorganisms from harmful aliens.
In addition, this protein label is no worse than fingerprints will help distinguish each of us from all other inhabitants of the earth. We smell our MHC proteins.
We unconsciously catch the scent of every person we communicate with. Our brain immediately conducts a molecular analysis, and turns its results into emotions. The immune system sends a signal of acceptance or alarm: this person looks like me, everything is fine. And that one over there is completely different, he has someone else's proteins, be careful — with him, too, you will not get healthy offspring.
And we feel that we like this one, but that one does not attract at all. It is these feelings that become the basis for choosing a partner.
We don't even notice that we react to the smell. But in the brain, the centers associated with libido and the centers associated with positive emotions turn on.
The female brain reacts more strongly to similarity‑dissimilarity. Apparently, because a woman is primarily responsible for the child, she bears and raises him. Therefore, evolution gave her the right to choose.
Even animals react not only to odors, we — even more so. The voice, the visual impression, and the emotions that the behavior of a possible partner causes matter. Therefore, males often arrange competitions and whole performances to please the females. This happens in animals, and people in the course of evolution have not forgotten this experience either.
The principle works here: too dissimilar can be an enemy, and you will not grow offspring with him. Therefore, the markers that the society has set are included. Everything that speaks about the similarity of the partner works: close traditions, the same upbringing, the same level of education.
The brain concludes: if these criteria are similar, it means that we imagine caring for offspring in the same way. And our union has prospects.
We feel alive when all levels of the body, psyche, and organism work simultaneously — from physical proximity to similar principles, algorithms of thinking and values.
The laws that have developed over tens of thousands of years of evolution push us to monogamous relationships.
Reproduction, if you look at it seriously, is not really about sex and not about pleasure. It's about having a baby and having our genes jump to the next generation.
In order for the birth to continue, it is not enough just to give birth to a child. It needs to be nurtured, go out and educate. It is difficult for warm—blooded animals to do this alone - the baby is born helpless and grows up for a long time. Therefore, in the course of evolution, those species where both parents took care of the offspring and helped each other survived and continued to develop. This means that they continued to live together and remained faithful to each other.
How this rule works can be seen in birds. It happens that a couple dozen chicks appear in one nest, and one mother will never be able to feed everyone: she will not have enough time or energy. Therefore, a dad is needed for survival — two birds will bring more food. Well, to stay together, you need to be monogamous.
Penguins have a similar situation. While one of the parents is looking for food, the other stays with the chick, hugs it to itself and does not allow it to freeze in severe cold. If the couple separated after the birth of the cubs, the offspring would have died. Hence, it is important for penguins to remain faithful.
Monogamy is primarily about reliable breeding of offspring. And our brain is so arranged that it pays us honestly for monogamous relationships — with positive emotions.
Our brain remembers about different behavior programs. Among them there are polygamous attitudes — they are more ancient than monogamy formed by evolution. In our brain, these opposing programs compete with each other.
Even monogamous birds have infidelities. It turns out that if you take blood tests from the chicks, the results will show that 20-30% of the cubs have a different biological dad.
Society also plays its role. Now he is actively pushing us towards polygamy. In a big city, a mother can raise a child alone, without any help. The more comfortable life is, the less need there is for a second partner to always be there. Therefore, new polygamous attitudes appear, which often take precedence over monogamous ones.
But these latest installations are very superficial. If the quality of life suddenly deteriorates, monogamous programs will immediately begin to dominate again.
We are very plastic, this is the strength of our biological species. But the basic settings do not disappear at the same time. And monogamy is one of them.
We have long moved away from animal models, so it is not only sex that is important to us. We talk to a loved one, make plans, remember the events that we experienced together.
Sex is only one of the components of communication between two loving people. It's just that sex is pretty boring.
Over time, attachment begins to play almost the main role in a couple. It depends on mutual contacts. It is very important for us to touch each other, hug and kiss, look into the eyes of our partner. That is, to do everything to feel that we are together.
That's why many people like dancing so much. This is a joint movement that triggers the synthesis of endorphins and brings joy, and close physical contact, and an exchange of views, and an attempt to learn something new together.
Even more important for a couple are common tasks and a cause that unites them.
We go to the goal together, we help each other. This is the basis of human attachment.