It's all down to two million years of evolution, say researchers in Australia.

Professor Jeffrey Braithwaite, from the University of New South Wales, says that the tribal culture in offices is similar to that of hunter-gatherers: "Prehistoric behaviours such as male domination, protecting what is perceived as their 'turf' and ostracising those who do not agree with the group, are more commonplace in everyday work situations than many of us want to accept."

And you may have your work cut out if you want to change him. "It's a surprise just how hard-wired this behaviour is," says Professor Braithwaite.

The press release (external website) was titled "Why your boss is white, middle-class and a show-off" - I've been banned from making any comparison with my boss, who is ... well, you can probably guess!