The Lowland Gorilla
The lowland gorilla is the largest living primate: it has no natural enemies or predators, but, sadly, is threatened by humans. Learn more about this primate.
The largest of the great apes, this massive gorilla has the strength of ten men, yet it is a gentle giant, displaying aggression only to defend its breeding rights. The stocky and muscular lowland gorilla has long, powerful arms to strip vegetation and bark from trees and strong jaws that mash fruit. A ridge of bone on the cheek of the skull forms an anchor for the powerful jaw muscles. The ridge is especially well developed in males, but in females it is smaller and in some cases may even be absent. Each hand has four long fingers and an opposable thumb. The gorilla is unable to spread its hands out flat and must walk, with fingers curled, on its knuckles. Each of his broad feet has four long outer toes and one shorter inner toe. The gorilla normally walks on all fours but sometimes stands and moves for short distances on two legs. At about ten years of age, when a male reaches sexual maturity, he develops a silvery white saddle on his back. Such males are known as silverbacks. The gorilla has small, humanlike ears almost completely hidden by fur. Its hearing is very sharp.
The lowland gorilla lives in low lying areas in central Africa. The two subspecies of lowland gorilla, the western and eastern lowland gorilla, occur in central Africa. Their populations are separated by barriers that gorillas cannot cross, the Conga River, broad plains, and dense, primary forest.
Lowland gorillas have a reputation for being ferocious. In fact, they rarely fight with each other or other species. A male acting as group leader performs an intimidating threat display, roaring and beating of the chest, if the group is threatened, but only rarely will he follow up with an attack. Western lowland gorillas eat considerably more fruit than their eastern cousins. Eastern lowland gorilla groups are slightly larger. An average group contains a dominant male, three of four females and their young. The male decides when the group eats, rests and sleeps. Unlike other great apes, it is the bonds between mature females and the dominant male, rather than bonds among females, that keep the group together.
The lowland gorilla mainly eats vegetation and in order to fuel and sustain its great bulk, has to spend most of the day foraging. The gorilla is a forest nomad, after feeding in an area for a while it moves on so vegetation can regenerate. It eats leaves, fruit and bark, stripping trees with its powerful jaws. It rarely drinks, as its diet provides most of its water requirements.
Lowland gorillas don’t have a distinct mating season. Females have monthly cycles, similar to female humans, and are receptive in the middle of the cycle. The dominant male of each group mates with the mature female, or females, in his group. After about nine months gestation, females give birth to one or rarely, two offspring. All members of the group cooperate in the rearing of the newborn. Unlike most primates, nearly all female lowland gorillas leave their parental group when they reach maturity, at about eight years of age. Females leave to join another group or a lone male who is searching for a mate.
Eastern lowland gorillas, with a wild population of only 3,000-8,000, are listed as endangered by the World Conservation Union, otherwise known as IUCN. Western lowland gorillas number some 40,000 and are listed as vulnerable. Laws that rule against the hunting and capture of gorillas are difficult to enforce, and the killing of gorillas goes on.