According to a study conducted by Robin Dunbar, professor of Evolutionary Anthropology at Oxford University- the human brain is capable of managing a maximum of only 150 friendships.

Dunbar’s number, roughly 150, is a measurement of the “cognitive limit to the number of individuals with whom any one person can maintain stable relationships”.

Dunbar derived the limit from studying social groupings in a variety of societies — from neolithic villages to modern office environments.

He found that people tended to self-organise in groups of around 150 because social cohesion begins to deteriorate as groups become larger.

Apparently, Dunbar’s number also holds true for social networking- you could have thousands of friends on Facebook, but the truth of the matter is: only about 150 of these would amount to “true” friendship.
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The interesting thing is that you can have 1,500 friends but when you actually look at traffic on sites, you see people maintain the same inner circle of around 150 people that we observe in the real world,

It then brings one to wonder if there really is any sense in having over 150 friends on Social Networking sites. Dunbar also claims that girls are more apt at keeping friends than guys;
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There is a big sex difference though … girls are much better at maintaining relationships just by talking to each other. Boys need to do physical stuff together.”

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