The mountain gorilla (Gorilla beringei beringei) is one of the two subspecies of the eastern gorilla. It is listed as endangered by the IUCN as of 2018. The fur of the mountain gorilla, often thicker and longer than that of other gorilla species, enables them to live in colder temperatures. Gorillas can be identified by nose prints unique to each individual Males reach a standing height of 161–171 cm (63–67 in), a girth of 138–163 cm (54–64 in), an arm span of 2 to 2.7 m (6 ft 7 in to 8 ft 10 in) and a weight of 120–191 kg (265–421 lb). Females are smaller with a weight of 70–98 kg (154–216 lb). This subspecies is smaller than the eastern lowland gorilla, the other subspecies of eastern gorilla. Adult males have more pronounced bony crests on the top and back of their skulls, giving their heads a more conical shape. These crests anchor the powerful temporalis muscles, which attach to the lower jaw (mandible). Adult females also have these crests, but they are less pronounced. Like all gorillas, they feature dark brown eyes framed by a black ring around the iris. Adult males are called silverbacks because a saddle of gray or silver-colored hair develops on their backs with age. The hair on their backs is shorter than on most other body parts, and their arm hair is especially long. Fully erect males can reach 1.7 m (5 ft 7 in) in height, with an arm span of 2.3 m (7 ft 7 in) and weigh 155 kg (342 lb). The tallest silverback recorded was 1.95 m (6 ft 5 in) tall with an arm span of 2.7 m (8 ft 10 in), a chest of 1.98 m (6 ft 6 in), and a weight of 219 kg (483 lb), shot in Alimbongo, northern Kivu in May 1938. There is an unconfirmed record of another individual, shot in 1932, that was 2.06 m (6 ft 9 in) and weighed 218.6 kg (482 lb). The heaviest silverback recorded was a 267 kg (589 lb) 1.83 m (6 ft 0 in) tall specimen shot in Ambam, Cameroon. (Source: Wikipedia.org, CC BY-SA)