Monkeys exhibit a behavior known as teeth chattering, which involves rapid, rhythmic jaw movements producing a distinct sound. This action communicates within their complex social structures. It is a non-vocal signal, often conveying meaning through facial expressions.
Decoding the Reasons for Chattering
Teeth chattering in monkeys serves a range of communicative purposes, with its meaning often depending on the social context and body language. One common function is as a threat display, where it can signal aggression. It may combine with intimidating behaviors like direct staring or yawning to expose canine teeth, as seen in baboons and mandrills. This warns off rivals or asserts dominance without physical conflict.
Conversely, teeth chattering can also convey submission or appeasement, especially between subordinate and dominant individuals. It reduces tension and signals non-aggression, preventing attacks. For example, Barbary macaques use chattering as a submissive signal. It can also be a gesture of reassurance.
Beyond conflict-related signals, teeth chattering plays a role in expressing excitement or during social greetings. Barbary macaques, for instance, may chatter their teeth as a friendly gesture, especially when bonding over a baby. This suggests an affiliative meaning in positive social interactions. The exchange of chattering can also strengthen social bonds and coordinate group interactions.
Subtle Differences in Chattering
The nuances of teeth chattering are conveyed through variations in its intensity, speed, or duration, subtly altering the message. Vigorous or prolonged chattering might indicate greater excitement or a more serious warning. The specific context helps to interpret these variations.
This behavior frequently occurs alongside other body language cues, like facial expressions or body postures, clarifying its intent. A “play face” or specific postures can accompany chattering to denote friendly interactions or submission. Unlike involuntary teeth grinding (bruxism) or shivering, which are physiological responses, monkey teeth chattering is a deliberate communicative action. It is a social signal, not merely a physical reaction to cold or stress.
Species That Chatter
Teeth chattering is a known behavior across various monkey species, especially among Old World monkeys. Macaques, including Barbary macaques and black crested macaques, frequently exhibit this behavior in contexts from friendly greetings to submission and threat displays. Baboons also engage in teeth chattering, sometimes as a sign of friendliness or submission, alongside dental displays like yawns showing large canines as a warning.
Mandrills are another species known for teeth chattering, signaling friendliness or as part of greeting rituals. While widespread in these groups, it is not a universal primate behavior. Contexts and meanings can vary slightly by species, reflecting diverse social dynamics and communication repertoires.