page_title: Dominance signal
section_title: Gorillas (Gorilla beringei graueri)
hierarchical_section_title: Dominance signal / Social dominance signals / Gorillas (Gorilla beringei graueri)
caption_attribution_description: Young gorilla drumming chest
context_page_description: A dominance signal is used in a dominance hierarchy or pecking order to indicate an animal's dominance. Dominance signals are a type of internal environment signal that demonstrate the signalers attributes. Dominance signals are necessary for several species for mating, maintaining social hierarchies and defending territories Dominance signals also provide information about an animals fitness. Animals have developed conflict management strategies to reduce frequency of aggressive incidents in competitive matters. This evolution is the basis of dominance signals.
  Dominance signals can be operationally defined by acts or displays produced by signalers, which conveys meaning messages to recipients such that the signal is met with a response and the response results in dominance being displayed. For example, hermit claws raise their claws performing a threat signal, which expresses intent to attack to challenger and the challenger makes a decision to retreat which reinforces signaller's dominance.
context_section_description: Gorilla's chest-drumming is a signal used to demonstrate social dominance. This non-verbal, rapid chest-drumming creates a sound because gorillas have air sacks on both sides of their throat. The drumming is often accompanied by screaming and non-specified sounds. This signal is used as a warning signal to young gorilla to back-down if they are trying to join their tribe. This signal will only cease if the young male backs-down or if they engage in battle. The young males are not challenging the dominant for courtship behaviour alone, but rather are trying for group-wide control. Chest-drumming is also used a sign of victory after a battle and demonstrates who is the male dominant. As gorillas are male dominant, females do not produce these dominance signals. Silverback gorillas also use chest-drumming to command their family to follow them, reinforcing familial dominance.
  Dominance signals that reinforce hierarchy are crucial for survival for animals like gorillas who are extremely aggressive. A Gorilla's chest drumming, for example, reduces intra-species aggression by making the dominant-subordinate relationship clear. For social animals like gorillas, having and maintaining a dominant male is crucial to maintain their way of life.
caption: A Young Gorilla chest-drumming.
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