Just like in humans, gorilla communication can occur through a variety of methods—body postures, facial expressions, vocalizations.
Gorillas use a variety of behaviors and vocalizations to communicate dominance. It can be as subtle as slightly moving out of the way of a dominant individual as he/she approaches; to making an appeasement vocalization, which is often accompanied by a submissive posture like crouching; to a full fledged display that includes throwing vegetation, chest beating, strut stances and even aggressive behaviors like hitting or kicking.
Facial expressions can say it all! Just like how you may be able to read a person’s mood by their expressions, sometimes you are able to with gorillas and apes as well. One common and distinctive expression is the play face! Play faces consist of an open mouth with low hanging bottom lip and no teeth showing. Juveniles are the most common individuals to display the play face. This facial expression is often paired with the gorilla equivalent of laughter!
“Smiling” and Yawning
You may occasionally see gorillas communicate in a couple of different ways by showing their teeth. One being “bared-teeth”, where the mouth is open and both rows of teeth are showing.
This is a sign of submission or appeasement and is thought to be tied to the origins of human smiling. Gorillas, particularly males, may also reveal their teeth through yawns. Yawning is thought to occur in context where males are distressed or anxious and could serve as a warning sign and display of dominance.
Gorillas have many different vocalizations to communicate alarm, distress, aggression, contentment, and group coordination. One of the most frequent vocalizations is the belch, which is used to convey a sense of contentment between individuals. Gorillas also hum or sing, this usually occurs in the content of finding a highly preferred food and usually involves several individuals or the whole group doing at the same time.
A chest beat can have multiple different meanings, the most well-known being in times of aggression in males. This style of communication is done by beating the chest with open palms, males have large air sacs located in their chests, which helps carry the sound over long distances. Chest beats are also common in younger gorillas, who do it while they are playing.
Click on the link here to hear what a chest beat sounds like!