On Facebook, people often have thousands of online friends, but how many of them could be counted on to help their friend in difficult circumstances? Not many, according to a new study by Robin Dunbar.
Dunbar is a renown anthropologist who came up with “Dunbar’s number,”—150—the maximum number of stable, close relationships the average person can maintain at the same time.
His study tried to find out if online networks like Facebook could help people “transcend” Dunbar’s number, that is, keep more close relationships with people. Dunbar analyzed a survey of 3,375 British Facebook users between the ages of 18 and 65, and found that although the average account had 150 followers, they could only count on 4.1 friends for emotional support during a crisis, and they could only count on 13.6 as part of their “sympathy group.”
The two numbers are similar to the ones found by Dunbar in offline studies, suggesting that Dunbar’s number applies to online relationships as well.
“The sizes of the two inner friendship circles did not differ from those previously identified in offline samples,” Dunbar writes. “Respondents who had unusually large networks did not increase the numbers of close friendships they had, but rather added more loosely defined acquaintances into their friendship circle.”
Moreover, although online social networks allowed people to maintain friendships over the web, they likely crowded out offline friendships. Younger people have more friends online, but tend to have smaller social circles offline.
Dunbar concludes that online friendships are subject to the same “cognitive demands” as offline ones, and therefore the maximum number of close relationships is similarly limited around 150, proving his law still applicable in the digital age.