When gorilla is 3 years old, it is able to crawl and move from one place to other. The gorilla becomes young at the age of 5 or 6.
The height of the gorilla stops increasing at the age of six. Weight of gorillas at this age is about 70 kilogram and height is around 4 ft. Female gorillas also mature at the age of six. Male gorillas mature at the age of about 11 or 12 years.
At the age of maturity, mountain gorillas get grayish or silver color hairs. This is why they are also called as 'blackbacks'. Female gorilla, on the other hand is termed as 'silverback'. The height of gorilla at the age of maturity is about 5.5 ft and after the age of maturity, the ceases to grow.
Though the longest living gorilla is recorded at the age of thirty five years, the actual life span of mountain gorilla is difficult to determine. But according to an estimate, mountain gorillas, in wild, have an approximate age of twenty to twenty five years. Wild gorillas are easily identifiable due to their extremely large size than ordinary gorillas and their silverback coloring.