There are endless clues to the Dunbar number, but what is it anyway, and why is it so important to our brains?
Robin Dunbar, Professor of Evolutionary Psychology at the University of Oxford, and Honorary Member of the Hungarian Academy of Sciences, is one of the few researchers to have a book named after him—a must-do now in all human evolution books.
The anthropologist will deliver his inaugural lecture on October 26 at MTA Szécház Neuroanatomy of friendship and society With the title and before that he gave an interview with mta.hu.
At the beginning of the interview, Dunbar spoke about the fact that the anatomical features underlying social skills are now typically examined using brain imaging procedures: In this way, they map “which parts of the brain are active when we engage in social interactions or even just think about other people’s states of consciousness” . They are also looking at how the size of people’s personal social networks – such as the number of family members or friends – correlates with the size of certain parts of the brain. revealed that
The task of a large part of the brain is to maintain and manage a person’s social network.
In addition to the limbic system and the cerebellum, the neocortex plays an important role in this, which “experienced a significant increase during primate evolution: in mammals, the neocortex typically accounts for 10-40 percent of the total volume of the cerebral cortex. The brain, in primates already accounts for what At least half, and in humans 80 percent.”
Primates have a primary interest in keeping the group together, which remains quite stable, thanks to the strong bond between individuals.
But maintaining many relationships is very stressful, which is why the neocortex has grown in size so much. Hence Dunbar’s idea: to see how the size of the neocortex of monkeys correlates with the size of their group and, as it turns out, strongly. Accordingly, the researcher estimated this by relying on the neocortex
What is the effective group size of a person: 150 came out, so this became Dunbar’s number.
But what is the real meaning of this? Let’s start with the fact that it sounds totally real, because researchers have tested this theory in countless ways — and it has stood the test.
- The size of the hunter-gatherer group corresponds to this figure
- Studying the military history of three centuries, they saw that armies experimented with different unit sizes, and finally agreed on a structure that corresponded to the layers of human social relations nearly a hundred years ago.
- They looked at Italian Alpine villages between 1250 and 1850, over a period of six hundred years, and found that the average population of villages in a given valley was 145, while the total population grew. In other words, more and more villages were established, but their population remained around 150
- The average size of the social network of family and friends of people living today is 150, that is, we are able to maintain meaningful relationships with this many people
- The number 150 turns out to be “amazingly common”: it seems that the information flow is not efficient in both smaller and larger networks.
It may have been noted that in the case of the military, the magic number 150 was not included, but the phrase “a structure that corresponds to the layers of human social relations”. what do you mean? Dunbar’s number can be divided into smaller circles and smaller numbers in which the closest, best, best, and average friends are placed.
“They almost triple from the inside out – 5 closest friends or family members, 15 good friends, 50 friends, etc. – but we don’t really understand why”
Explain the world. By definition, moving from the inside out reduces the level of help and emotional charge of the relationship. According to measurements, 60 percent of the time we spend in our social relationships is spent on our 15 best friends. (…) “This is also the basis for the organization of all modern armies. Squadrons, detachments, companies, battalions organized according to similar principles.”
The role of the social network and online meetings are also discussed in the interview – both of which are thoroughly investigated by researchers.
It is not surprising that maintaining close human relations requires effort and time, and the time available for social activities is limited. According to the research, there are people who are able to maintain a larger network with the help of online connectivity – but the average is 149. And don’t think of it as a hobby: Dunbars have already received “amazingly large blocks of data from Facebook, the largest of which contains Interaction data of 61 million profiles” from Facebook. So this is how the average of 149 turned out, so it looks like we can really make a meaningful relationship with that many people.
The whole conversation You can read it here.
(Source: MTA, Photos: Unsplash)
You may also be interested in:
