The principle of top down hierarchy seems extraordinarily resilient in human societies. But why have we come to organise ourselves this way? Is it to be more efficient and effective? Or, is it because some people will always be driven by instinctive greed and desire for power?
Bridget Kendall talks to professor Peter Turchin, a biologist trying to trace the hidden dynamics of history, Anja Kanngieser, a social geographer who is interested in alternative networks which link us horizontally, and political cartoonist Martin Rowson, an artist whose work would founder without the rich and the powerful to poke fun at.