cheating and co-operating...,

abc.net.au | Lying, cheating and other forms of Machiavellian skulduggery seem to be the inevitable evolutionary consequences of living in co-operative communities, suggest UK scientists.

Instead of viewing deception and co-operation as polar opposites, Luke McNally from Trinity College Dublin and Andrew Jackson from the University of Edinburgh say we might do better to think of them as two sides of the same evolutionary coin.

"Deception is an inherent component of our complex social lives, and it's likely impossible to separate the good from the bad; the darkest parts of our psychology evolved as a result of the most virtuous," says McNally.

The researchers lay out their evidence in the latest issue of the Proceedings of the Royal Society B.

First, they use game theory to show the evolution of co-operation creates pressures that favour the evolution of deception.

In their scenario, individuals have three options: to always cheat and not help others; to reciprocate the help that others offer; or cheat and try to conceal this cheating by deceiving others.

"When reciprocal co-operators interact with honest cheaters, they spot their cheating and stop co-operating with them," McNally explains.

"However, as deceivers are better at hiding their cheating, reciprocal co-operators find it harder to spot their cheating.

"This means that the deceivers are able to gain co-operation without having to co-operate themselves, allowing deception to evolve."

The researchers back up this theory with real-world evidence gathered from studies of deception in 24 different primate species.

They show deceptive behaviour is more common in species that co-operate more.

"Our comparative analysis shows the more co-operation a species engages in the more it engages in deception, which is what our model predicts," McNally says.