If you have thousands of friends on Facebook, most of them are not your real friends, reports The Sunday Times of London.
According to a recent study by Oxford University professor of Evolutionary Anthropology Robin Dunbar, a human brain is limited to keeping up with about 150 meaningful relationships, regardless of how many Facebook friends you might have. This is in line with Dunbar's earlier research on the matter, in which he concludes that there exists a theoretical "sweet spot" for the number of relationships a human can effectively manage. Throughout history, people have formed social groupings of about 150, as larger groupings quickly begin to deteriorate and lose social cohesion.
(Source: PC World)