Hey, monkey: Just 'cos your mates eat FOUL corn, YOU have to eat it too?

Monkeys are just as prone to peer group pressure as humans, according to new research.

Boffins at the University of St Andrews found that primates are heavily influenced by the behaviour of their peers, just as humans are.

The discovery has been hailed as a rare example of "cultural transmission" in non-human animals.

Professor Whiten, one of a three-strong team that conducted the research, said: "As the saying goes: 'When in Rome, do as the Romans do.' Our findings suggest that a willingness to conform to what all those around you are doing when you visit a different culture is a disposition shared with other primates."

The team observed 109 wild vervet monkeys at the Mawana private game reserve in South Africa and originally set out to find how much baby monkeys are influenced by their mother's behaviour.

But they found that it wasn't just mums that had an influence on babies, but friends and neighbours.

Professor Whiten added: "The males' fickleness is certainly a striking discovery. At first sight their willingness to conform to local norms may seem a rather mindless response – but after all, it's how we humans often behave when we visit different cultures.

"It may make sense in nature, where the knowledge of the locals is often the best guide to what are the optimal behaviours in their environment, so copying them may actually make a lot of sense."

The research involved offering the monkeys two types of corn. One was painted blue and tasted lovely, while the other batch was coloured pink and made to taste awful.

The scientists found that monkeys quickly became used to the colours and even when both were made to taste the same, all the vervets decided to opt for the "yummy" blue corn.

Then, when baby monkeys were placed among the group that had already been trained to eat the blue corn, researchers were astonished to see that they wolfed down the same corn as the grown-ups.

They also observed the vervets during the mating season, when males migrate between social groups in search of a female to cop off with.

When the horny monkeys arrived in a new group, they began eating the same colour of corn as the rest of the group. The only monkey who didn't do so was the top ranking in his group, who presumably was so attractive to female monkeys that he didn't need to bother fitting in with the locals' behaviour.

Dr Erica van de Waal, who also worked on the study, said: "The willingness of the immigrant males to adopt the local preference of their new groups surprised us all.

"The copying behaviour of both the new, naïve infants and the migrating males reveals the potency and importance of social learning in these wild primates, extending even to the conformity we know so well in humans."

Professor Frans de Waal (no relation) of the Yerkes Primate Center of Emory University said the experiment was "one of the few successful field experiments on cultural transmission to date, and a remarkably elegant one at that".

The research is published today in the journal Science. ®