If there is any signature action of mountain gorillas, it is to quickly beat the chest with their hands to produce a "boom boom" drum sound. According to a recent zoological study published by Science Reports, a subsidiary of Nature Research, this chest beating behavior may convey important information about their body shape, and at the same time help them identify different individuals based on sound. This finding demonstrates nonverbal behavior or contributes to the communication of mountain gorillas. In the past, it was thought that mountain gorillas pounded their chests to exchange information, but the exact nature of the information was not always clear. From January 2014 to July 2016, Edward White, a scientist at the Max Planck Institute for Evolutionary Anthropology in Germany, and colleagues observed and documented in detail 25 wild adult male silverback gorillas supervised by an agency in Rwanda's Volcanoes National Park called the Dian Fossey Gorilla Foundation. The researchers determined the body size by measuring the distance of the gorilla's shoulder blades in the photo. Using recordings, the scientists measured the duration, number of times and sound frequencies of 36 36 throbbing chest blows by six male gorillas. The research team found that larger males beat their chests at a significantly lower frequency than smaller males. They noted that larger males also have larger laryngeal sacs, resulting in lower vocal frequencies when beating their chests. The length and frequency of chest beatings varies from gorilla to gorilla. These have nothing to do with body size, but may enable other gorillas to recognize individuals who are beating their breasts. With this in mind, the researchers believe that gorillas may be able to use the sound of pounding their chests to communicate with each other in the dense tropical forest where they live, even though they cannot see each other. They speculate that mountain gorillas may use chest-pounding messages to declare mate selection and assess a competitor's ability to fight. (Science and Technology Daily reporter Zhang Mengran)
Source: Science and Technology Daily