By CAPosts 08 April, 2021 - 03:19pm
A very representative gesture of gorillas that has been portrayed countless times in documentaries, movies and others is when they beat their chest . Contrary to what one might think, it is not a battle cry. Have you ever wondered why they do it? Here we tell you .
© Provided by Milenio Gorilla beating his chest (DFG Fund)
These animals that beat their chest quickly with their hands like a drum can thus transmit information about their body size and allow the identification of individuals . This is suggested by a study published in the journal Scientific Reports .
© Provided by Milenio Research results
The result shows that non-vocal behaviors can contribute to communication in mountain gorillas . Although it had previously been suggested that gorillas could beat their chests to transmit information, the exact nature of that information was unclear.
Researcher Edward Wright of the Max Planck Institute for Evolutionary Anthropology in Germany observed and recorded 25 back gorillas Silvery adults and wild animals, monitored by the Dian Fossey Gorilla Fund organization in the Volcanoes National Park, in Rwanda.
According to a statement from the institute , the size of the body was determined from photographs by measuring the distance between the shoulder blades gorillas . Using sound recordings, the authors measured the duration, number, and audio frequencies of 36 breast strokes performed by six of the males.
The authors found that the audio frequencies of breast strokes performed by the largest males they were significantly lower than those of the smaller males. Larger males may have larger air sacs near the larynx, which could reduce the frequencies of the sound they produce when beating the chest.
Variations in the duration and number of chest strokes were also observed. different gorillas These variations are not related to body size, but may allow individuals striking each other to be identified
The authors suggest that the sound of these strokes may allow mountain gorillas to communicate through the dense tropical forests in which they they live , where it is often difficult for them to see each other. They speculate that mountain gorillas can use the information transmitted through chest strokes to choose a partner and assess the fighting ability of competitors .