At night, adults and sub-adults build individual nests from branches and leaves on the ground, in low vegetation, or in trees. Females also keep their infants nearby him, fostering a bond between the silverback and their offspring while also ensuring his protection from predators and other adult males. Females also leave the group upon reaching sexual maturity, joining lone males or other harems. However, they rarely stay with the first male to which they attach themselves. Females in the wild begin to breed when 10 years old, males from 15 to 20 years.
Breeding can take place anytime during the year.
Birth of a single young, weighing about 4 lb, occurs after a gestation period of 250 to 270 days. The mother nurses the infant for 2.5 to 3 years and carries it for the first few months of life. At eight or nine weeks it begins to crawl and walks in seven to ten months. Adults have been known to live to almost 50 years of age. Despite its ferocious image, the gorilla is not an aggressive animal.