Shrieking during sex can disturb the neighbours in the jungle just as much as in suburbia, so female chimpanzees make a conscious effort to keep the noise down, researchers have found.

Female chimps, much like humans, worry that they will be overheard and interrupted. But whereas embarrassment can keep humans quiet, it is fear that reduces chimps' sex noises to a whimper. This is because high-ranking female chimps will not tolerate attempts at breeding by their social inferiors.

Researchers monitoring chimps in Uganda found that females were much less likely to cry out during sex when they knew other females were within earshot. Those that were unable to suppress their “copulation calls”, or were unaware that they had an audience, were more likely to be interrupted and beaten by a higher-ranking chimp.

Crying out during sex is as much a feature of human and chimp lives as it is of those in the wider animal kingdom, including elephants, lions and brown rats.

The study, published by the online journal PLoS ONE, found that it was a useful tool for female chimps to alert males that were ready to mate.

To the surprise of the researchers, the calls provoked little competition between males.The females were more concerned with mating with as many males as possible, rather than select the fittest specimen. When they are in the mood, female chimps can mate up to 20 times a day.

“The female chimps we observed seemed to be much more concerned with having sex with as many different males as possible, without other females finding out about it, than causing male chimps to fight over them,” said Sion Townsend, of the University of St Andrews.

“Some of the older literature shows human females completely suppress calling for fear of neighbours hearing. We call it audience sensitivity in chimps. It suggests there are similar evolutionary mechanisms between the two species.”

It seems doubtful that female chimps elicit the same degree of pleasure suggested — fake orgasms apart — by the passionate cries that humans make during sex.

After looking at the “thrust rate and the length of copulation”, the researchers from St Andrews and the Max Planck Institute, in Germany, decided that the calls by chimps were a tactical device to attract further male interest.

Times Recommends

• Plan for 9/11 trial in New York divides the city
• Beijing gets the jitters as Obama flies in
• Potshot Palin settles scores