Social grooming: what is it, characteristics, effects and functions?

Let's see what social grooming is, a behavior present in many different animals.

Hygiene is widespread in the animal kingdom. Many species go to great lengths to keep their coats, scales, feathers and fur clean, sometimes doing so as ritualistically as cats do.

However, no matter how much experience and practice one has cleaning oneself, sometimes it is not enough to clean the entire body. Reaching all parts of the body is difficult, almost impossible depending on the anatomy of the animal and will require assistance.

Social grooming is the set of behaviors in which several individuals clean each other, and it has a lot of other advantages.and it has a lot of advantages beyond hygiene. Let's delve into what this peculiar social behavior is all about.

What is social grooming?

Surely on more than one occasion you have noticed that cats spend a lot of time cleaning themselves by licking each other. It is a behavior that does not go unnoticed because of how explicit it can be and that, in addition, they do it very often, dedicating about 15% of the day to it.They devote about 15% of their day to their grooming habit, which is somewhat excessive from our human perspective. They do it to get rid of loose hair, sand and other foreign objects that may have gotten stuck in their carefully groomed fur.

But our feline companions are not the only animals obsessed with hygiene. In the animal kingdom we can find all kinds of species that regularly clean their fur, feathers, scales and skin to get rid of insects, leaves, straw, twigs, mud or remains of food and dead skin. This individual self-cleaning and grooming behavior is necessary to keep the skin in good condition, but sometimes it is not enough and some external help is required.

In social or gregarious animals, social grooming is an activity in which an individual cleans, deworm or cares for any other an individual cleans, worms or otherwise cares for the body or appearance of another individual in its group.. By receiving help from another member of the herd, the recipient animal is able to sanitize areas that it would never reach on its own, as well as having an intimate and mutually cooperative time that strengthens social bonds.

Social grooming is not only manifested in the form of deworming, although this is one of the most common. Actions such as scratching, petting or massaging are also considered grooming. These behaviors are socially very interesting, since it has been seen that friendships and other relationships established between two individuals who groom each other are often long-lasting, becoming as deep and stable as a relationship with our best friend.

• You may be interested in, "What is prosocial behavior and how does it develop?"

Social grooming in primates

Social grooming is one of the most studied social activities in primates. In the primatological world, this phenomenon is often referred to with its Anglo-Saxon terminology of "social grooming", and it is known that in "cousin" species such as chimpanzees, this grooming serves to strengthen the primate's social behavior. this grooming serves to strengthen relationships, reinforce the social structure and strengthen family and pair bonds.. It is also used as a means of reconciliation and a strategy to resolve conflicts and, for this reason, primatologists call social grooming "the cement that binds the primate world".

It has been seen that this type of behavior also serves as a form of currency, being used as a resource with which exchanges of food and sex are made. It is also done "for free", simply to kill time and get rid of boredom, although it is also used as a relaxation measure, reducing stress and tension so much that on more than one occasion chimpanzees have been seen to fall asleep while being wormed by others.

Why does this behavior influence social bonds?

We can see that social grooming, both in primates and in other animal species, is a behavior that allows the establishment and creation of long-lasting relationships between individuals. Now, what is it that makes social grooming a social bonding strategy? What are the neurological mechanisms or psychophysiological explanations behind this phenomenon?

1. C-fibers

As we have discussed, social grooming can be carried out in multiple ways, including petting, scratching, and massaging. It has been found that, when one individual performs this behavior on another, the C-fibers of the animal being groomed are activated.The C-fibers, which are related to pleasurable sensations and involve the limbic system and the orbitofrontal cortex, have been found to be activated when an individual performs this behavior on another.

2. Endorphins

Sometimes the chosen grooming behavior can be a bit rough, rough and coarse, just like a massage. At first, the massage may become a little painful, but gradually it becomes a pleasurable sensation. Why does this happen? The explanation is neurophysiological, being involved endorphins, hormones and neurotransmitters that are released in the brain and that induce the sensation of pleasure and relaxation, as well as act as Pain relievers.in addition to acting as pain relievers.

The importance of endorphins in social grooming has been scientifically proven. Research has shown that animals given endorphin blockers engage in excessive grooming behaviors, as if they are never satisfied despite being scratched or massaged for a long time. In contrast, animals injected with endorphins act as if they are already satisfied, and are disinterested in giving or receiving grooming.and are disinterested in giving or receiving grooming.

3. Oxytocin

Finally, it is worth mentioning a study conducted by the Max Planck Institute in Germany which showed that oxytocin also appears to be involved in the formation of social bonds related to mutual grooming. This study, conducted by Crockford and colleagues, found that oxytocin levels were higher in chimpanzees that had just performed social grooming on individuals with whom they had greater trust or had groomed previouslycompared to chimpanzees that had groomed a new individual, the latter having lower levels of this hormone.

The same research also showed that oxytocin levels were equally high after grooming both related and unrelated individuals, as long as there was a significant bond and a history of previous social grooming. Oxytocin is known to act neurologically in the reward and social memory systems, so the Max Planck Institute study shows that oxytocin plays a key role in the maintenance of social relationships beyond genetic ties.

And what does this imply for humans?

Humans are still social animals, and proof of this is that we maintain relationships for long periods of time.. If we stop to think for a brief moment, the reality is that we are constantly engaged in social grooming, engaging in behaviors that would be nothing more than more complex modalities of behaviors such as scratching, massaging, and petting.

Behaviors that can be considered social grooming in one form or another are giving a warm handshake, cuddling with our friends, and snuggling with people we care about. Although we may not realize it, these forms of social grooming are fundamental to our ability to connect with others. and introducing new ones such as massaging our partner or cuddling our children can help us to improve the well-being of our social environment, avoid arguments, create a climate of calm and, ultimately, strengthen bonds.