How does a gorilla grow up?
As a rule, gorillas 'mother' their children very little. Experienced females in particular don't concern themselves much with their offspring apart from carrying, nursing, grooming and protecting them. In the first few months, a young gorilla is constantly in physical contact with its mother. At first the mother supports the baby with one hand, but even on its first day it can cling to her fur without help for a certain length of time. Physical contact with the mother starts to decrease at the latest in the baby's 4th or 5th month, when it starts to walk quadrupedally.
In general, gorilla babies are nursed for at least 2 years. At 4-6 months they start to put plant parts into their mouth and to bite on them. At 8 months they regularly ingest solid food. At approximately 3 years they start to become independent because their mother gives birth to the next baby. In spite of this, mother and older offspring maintain a strong relationship.
From its first day of life, the baby is part of the group. Under the protection and control of the mother it slowly grows into the community. As soon as the mother permits the others to approach, they will look at the newborn baby, smell and touch it. At latest when the young gorilla starts moving away from its mother, the other animals seize the opportunity to make contact with it. Usually, adult gorillas will hold, carry and groom the infant, while young gorillas will try to play with them.
When female gorillas reach sexual maturity, they develop a hormone cycle similar to that of human females. Female mountain gorillas can ovulate for the first time when they are about 8 years old, but usually the first ovulation happens in their 10th year. Captive gorillas usually reach sexual maturity faster, sometimes in their 6th year. By comparison, girls of western industrialized countries reach sexual maturity at 12 years at the earliest.
Reaching adulthood, female gorillas usually leave the group they were born in and join a new partner. In their choice of males, gorilla females can be quite particular: Usually they transfer to a new group several times before they settle down with a certain silverback male.
In male gorillas, puberty extends over several years. This is when a blackback male turns into a silverback - the silvery back, the huge canines and the other secondary sexual characteristics develop. When exactly males reach sexual maturity has not yet been determined. In captivity, occasionally individuals just under 7 years old turn out to be fertile.
Free-ranging mountain gorilla males are fully grown at approximately 15 years of age. Like the females, they usually have to leave the group on reaching adulthood. After leaving, they often stay on their own until they are joined by females.