All about friendship, scientifically speaking. Part I

On average one person has facebook on 350 friends, in 2013 a study was done in which the data of all the users of this social network in the world were analyzed and graphs like the one above were made, in which the number is observed of friends according to the age or the one below that shows the civil status of the users according to age, where there is a considerable decrease in the number of single people as the years go by, very interesting.

But the most interesting is the following, the distribution of the number of friends per user has a peak in friends and is decreasing little by little, you see the orange pill down on the right, (red circle) exists because the limit of friends on Facebook is 5000, so all the people who have five thousand friends or more accumulate there, is the point at which Facebook considers that you can not have more friends, but really how many friends we can have.

The number of Dunbar, is the maximum number of people with whom one can maintain stable social relations, this number was developed in the 90s by the anthropologist Robin Dunbar, who theorized that its value was 150 people, based on the size of the cerebral cortex and its ability to process.

The origin of this number goes back to the first primatologists, who noted in their research, that given their highly social nature, non-human primates have to maintain a personal contact with the other members of their social group, this suggests that depending on the species, the maximum number of friends varies, depending on the size of the neocortex, the brain of that species.

But what is considered to be someone's friend? every day and depending on where you live, you can get to cross you with thousands of people, of all these you will know the name of some, of them in fact of a very small fraction, but know the name of someone and greet him on the street, not means we are friends of yours is only an acquaintance, the number of a Dunbar, refers to the number of people with whom you can have a relationship that involves at least a minimum of trust and obligation; a personal story that goes beyond knowing names and faces.

During his research Robin Dunbar found that the size of historical tribes and villages was similar to the one he had previously calculated found 150 as the estimated size of a farmer group of the Neolithic age, 150 as the point of bankruptcy and separation of a settlement of Euteritas, 200 as the maximum number of academics in the subspecialization of a discipline, 150 as the basic size of a professional military unit in ancient Rome and in modern times since the sixteenth century, many manuals or economics books have been written that what they are trying to explain is basically that if you want a company or organization to work perfectly you must not exceed 150 individuals.

A clear example is that of Gore-tex, a company in wetsuits, hiking boots and ponchos; its founder decided to ignore Dunbar's number and distributed all its employees in small factories of up to 150 workers, in those factories everyone knew who was who, who was the manager, who was the accountant, who was the one who made the sandwiches for lunch, then the company numbers began to go better than ever, since 1984 the company wins a position in the annual list of Fortune magazine of the USA, 100 Best companies to work with, this year won no less than the seventeenth Market Stall.