A four-year study by sociologists at The University of Manchester has found that women are much more likely than men to make deep and lasting friendships.
The investigation into social networks by the University's Research Centre for Socio-Cultural Change found that men are more fickle and calculating about who they should be friends with.
Women on the other hand, stand by their friends through thick and thin.
Adding to the bad news for male prestige, the study confirms the stereotype that men are likely to base their friendship on social drinking.
Of the 10,000 individuals studied who took part in the 1992 to 2002 British Household Panel Surveys, women are much more likely to stay with the same friends.
Single people, older people and white collar workers are also good at paring up.
Middle class people are more likely to cast their net of friendship far wider, whereas the working class tend to stick to their own kind.
Dr Gindo Tampubolon said the findings on female friendship were doubly significant because the data suggests we are much more likely socialise with people from our own gender - 75 per cent of best friends were with the same sex.
Dr Tampubolon, who is based at the School of Social Sciences, said: "Friendship between women seems to be fundamentally different to friendship between men.
"It's much deeper and more moral: it's about the relationship itself rather than what they can get out of it.
"Women tend to keep their friends through thick and thin across geography and social mobility.
"And women's view of friendship has something to do with how they express themselves and form their identity.
"Men, on the other hand are more fickle with their relationships and seem more interested in 'what's in it for me'".
He added: "The findings reflect our view that friendship is not a choice. We have contact with friends, family, neighbourhood and work which we are or are not able to turn into friendships.
"Middle class people are more adept at doing this and tend to define friendship more widely such as work, family and the pub.
"Working class people, on the other hand, are more limited: they're likely to form a best friend with another working class person."
Professor of Sociology Mike Savage said: "This research draws upon a tradition of inquiry known as social network analysis, developed by Professor John Barnes who was based here at the Victoria University of Manchester in 1952-1953.
"SNA is able to analyse social structures using a series of algorithms and we wanted explore its application in this area and others.
"It is now used widely by business including the Google search engine and Amazon's recommendations page.
"SNA is very relevant to the work of Harvard University's Professor Robert Putnam, and should inform our recently announced collaboration with Harvard on social change."
For more details, visit www.cric.ac.uk/cric/projects/socialnetwork/
Source: University of Manchester
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