The claims by Dr Ian Robertson may go some way to explain the outlandish and impulsive behaviour of city fatcats, tycoons and celebrities.

Writing in the Daily Telegraph today, he said: ‘Baboons low down in the dominance hierarchy have lower levels of dopamine in key brain areas, but if they get ‘promoted’ to a higher position, then dopamine rises accordingly.

‘This makes them more aggressive and sexually active, and in humans similar changes happen when people are given power.