The popular image of a gorilla that comes to our mind whenever we think about the creaturefeatures it thumping its chest. While we may think that there is no logic to it, a recent study by German researchers argues otherwise. According to a report in DailyMail, researchers who made this study on male Gorillas in Rwanda discovered that the Silverback species stand up and beat their chest as a form of communication.The drumming noise generated by them is their way to convey how big they are and to show their identity.
The study also shows that larger gorillas make deeper noise while beating their chest when compared to the small ones and the pattern of chest-thumping is distinct for each one of them.The idea behind beating their chest by these gorillas is to prove dominance over other males, while trying to impress the female counterparts.
For the study, the researchers analyzed video of 25 male gorillas from Volcanoes National Park, Rwanda. The exact body size of these creatures was calculated by measuring the distance between their blades and shoulders. A systematic data that recorded the number of beats and the beat rate was then arranged according to the size and age of the gorillas.
Six males were also audio-recorded, capturing a total of 36 chest beats with the duration of the beating, number of hits, and the frequency of the produced noise. The audio recordings’ study helped to establish a correlation between frequency and gorilla body size — bigger males made a deeper sound.
Though the gorilla chest beats are not vocalizations, they are considered to be a form of gestural communication that can be both heard and seen.
The researchers carrying out the study believed that the lower frequency sounds are created by the bigger sized animals because they have bigger air sacs around their voice box which amplify the sound. They, however, emphasized that the duration and number of chest beats were not related to the size of the gorillas. Instead, the team believes the variations in the number of beats, beat rate and total duration may allow individual gorillas to be identified, acting as an audio signature.
This would help gorillas identify one another across the dense forests in which they live, researchers speculate.The research findings will be published in journal, Science Report.