Adding credence to the cliche that "birds of a feather flock together", a recent study has suggested that our choice of friends is dictated by shared interests, more than our fondness for them.
Scientists from the University of Southampton, Royal Holloway, University of London, and the Institute of Zoology at London Zoo found that having enthusiasms and hobbies formed a strong bond but when we change those interests we change our friends.
As part of their study, the researchers examined Facebook style sites to try and unlock the secrets of real life friendship and sometimes it could be as simple as having the same favourite X Factor contestant, reports the Telegraph.
Millions of people are members of online social networks such as Facebook, or Twitter, where they join 'groups' according to their likes, or hobbies.
This phenomenon leads to friends being grouped more and more by cliques, and led academics to analyse the social butterfly effect - how we change friends throughout our lives.
During the study, researchers built a computer model of a real social network.
They discovered that throughout society we often form cliques and circles of friends with common interests, such as politics, music, religion, sport or the same profession.
Even if friendships are fleeting, we gravitate to those who enjoy the same things we do or support the same football team.
The researchers came to the conclusion that people go from clique to clique as their interests change, usually forming a tight knit of friends.
The study is published in the Journal of the Royal Society Interface.