The Big Idea: Dunbar's Number

Sunday 20 May



The Big Idea explores the best new ideas reshaping our world. In this episode presenter David Edmonds finds out about Dunbar’s number.

A great advantage of the internet and social media is that they allow us to keep in touch with all our friends, even when they move away. That means our group of friends can carry on expanding indefinitely. Except, says anthropologist Robin Dunbar, it can’t. There’s a limit to the number of friends we can have. It is known as Dunbar’s number. Dunbar has investigated friendship, including the stark differences between how male and female friends interact. The Dunbar number has implications for the running of organisations – such as companies and armies.

  • Produced by Ben Cooper for BBC World Service.