London, May 9 (ANI): Female gorillas deliberately clap their hands to attract the attention of male silverbacks and infants over long distances, which helps them keep their family together, according to a study.
This is the second time that such behaviour has been recorded in wild western lowland gorillas in the forests of central Africa.
"What struck me most was how it was conducted in such a controlled and deliberate manner while in a bipedal position; much like a human would hand clap," the BBC quoted Ammie Kalan of Oxford Brookes University, in Oxford, UK, as saying.
She added: "A female was able to exert control over her infant's behaviour by hand-clapping. Which did remind me of a human mother."
For their research, Kalan and her colleague Hugo Rainey, from the Wildlife Conservation Society, observed the gorillas at the Lac Tele Community Reserve Project in the Republic of Congo.
The researchers found that captive male and female gorillas occasionally clap their hands, either to display enthusiasm or to attract the attention of human keepers.
The researchers recorded hand clapping among four separate groups of western lowland gorilla, and observed five adult females clapping their hands, out of which four were mothers with infants present.
Each time the female clapped her hands twice in rapid succession in front of her body, and, on two occasions, the researchers noticed that the behaviour was to alert a male silverback to the presence of the human observers.
On another occasion, the researchers startled three females in a tree, and they heard them hand-clap five times in succession, with at least one minute between each.
"We believe they were attempting to contact the silverback even after we were no longer posing a threat," said Kalan.
Once they also saw a mother suddenly clap her hands at her infant, who stopped playing, while other adults stopped foraging.
Then, all of them followed the mother's gaze, who was looking at the researchers and the whole group moved away shortly after.
Kalan said: "It's a form of gestural communication that has largely been overlooked by gorilla researchers. It's used as a form of long distance communication with the silverback, even when humans are not posing an immediate threat, as well as to get the attention of group members. The hand clap allows the gorillas to maintain group cohesiveness."
The study also supports the idea that gorillas might develop different ways to communicate depending on the varying culture of each group.
The discovery has been reported in the journal Primates. (ANI)