Researchers studied the chimps in the Bundongo Forest, Uganda
Female chimps would rather have sex with multiple males than find the strongest mate, researchers have found.
A study by St Andrews University has found that females try to keep quiet during sex so others do not find out about their activities.
That prevents unwanted competition from females and allows them to have more sex with other chimps undisturbed.
The research, published in the Plos One journal, has shed new light on the mental capacities of chimpanzees.
Psychologists Simon Townsend and Dr Klaus Zuberbuhler observed their behaviour in the Bundongo Forest, Uganda.
They found that chimpanzee females use copulation calls strategically to enlist the future protective support of males against aggressive group members, especially other females.
The females produced more copulation calls when high-ranking males were around but concealed their sexual activity when high-ranking females were nearby.
Mr Towsnend said: "Competition between females can be dangerously high in wild chimpanzees. Our findings highlight the fact that these females use their copulation calls in highly tactical ways to minimise the risks associated with such competition."
The function of copulation calls in female primates has been debated for years. One common hypothesis suggests that such calls enable females to advertise their sexually receptive state to mates, which in turn incites competition amongst males.
According to this idea, the successful female ends up with the strongest partner and achieves the highest quality offspring.
However, the new study found no evidence for such male-to-male competition or any link between hormonal state and sexual activity.
Dr Zuberbuhler said: "Copulation calling may be one potential strategy employed by female chimpanzees to advertise receptivity to high-ranked males, confuse paternity and secure future support from these socially important individuals."
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