Despite social networks like Facebook and Twitter, most people will only ever have a handful of good friends, putting most of their efforts into communicating with small numbers of close friends or relatives.
They often operate unconscious one-in, one-out policies so that communication patterns remain the same even when friendships change, researchers said. “Although social communication is now easier than ever, it seems that our capacity for maintaining emotionally close relationships is finite,” said Felix Reed-Tsochas from the University of Oxford.
“While this number varies from person to person, what holds true in all cases is that at any point individuals are able to keep up close relationships with only a small number of people, so that new friendships come at the expense of ‘relegating’ existing friends,” said Reed-Tsochas.
The study combined survey data and detailed data from mobile phone call records that were used to track changes in the communication networks of 24 students in the UK over 18 months as they made the transition from school to university or work.
At the beginning of the study, researchers “ranked” members of each participant’s social network (friends and family) according to emotional closeness. They discovered that, in all cases, a small number of top-ranked, emotionally close people received a disproportionately large fraction of calls.
Within this general pattern, however, there was clear individual-level variation. Each participant had a characteristic “social signature” that depicted their particular way of allocating communication across the members of their social network.
Researchers discovered that, even though participants’ relationships changed and they made new friends during the intense transition period between school and university or work, individual social signatures remained stable.
Participants continued to make the same number of calls to people according to how they ranked for emotional closeness, although the actual people in their social networks and/or their rankings changed over time.
“As new network members are added, some old network members are either replaced or receive fewer calls, said Robin Dunbar, Professor of Evolutionary Psychology at the University of Oxford. The study was published in the Proceedings of the National Academy of Sciences.