The Social Structure of Gorillas
Typically gorillas can be found living in groups of between three and thirty members. Groups are usually comprised of a single adult silverback and three to four adult females. Other immature males and females younger than eight may also be part of the group. The adult male is the leader and protector in this type of grouping. Groups of bachelors are also common, with an older dominant male as the primary leader and protector.
Adult females will often transfer to other social groups if the only adult male is her father as she will need a suitable male to mate with. A female may transfer groups multiple times before deciding which one to stay with. Adult males that have reached sexual maturity will usually form a new group or will transfer to a group of bachelors.
Gorillas will often establish and follow a set schedule that includes waking, eating, activity, traveling, preparing for sleep, and sleeping. Schedules and other behaviors including what foods to eat, social responses, child rearing, and sexual behavior are learned by children by watching their mothers and other adults.
Gorillas are affectionate and patient with children and often take the time to play with younger members of the group. When necessary, children are disciplined with displeased body postures and looks as well as with stern vocalizations that sound to humans like deep grunts.
In total gorillas can communicate with about twenty-five different vocalizations, some of which can be heard up to a mile away. When gorillas are happy they can vocalize in numerous ways to show their pleasure including chuckling and purring. They will also smile when pleased. Short barking sounds can be used to indicate interest or curiosity.
Gorilla groups tend to avoid each other but when a confrontation does occur posturing can occur. Typically the leaders of the groups will stay for a confrontation while other members of the group leave. The leader, usually a silverback, will stand upright to appear larger and begin beating on his chest, roaring, and tearing vegetation to display strength and domination. Physical confrontation is rare.