The mountain gorilla inhabits the Albertine Rift montane cloud forests of the Virunga Volcanoes, ranging in altitude from 2,200 to 4,300 m (7,200 to 14,100 ft).

The word gorilla comes from the history of Hanno the Navigator (c. 500 BC), a Carthaginian explorer on an expedition to the west African coast to the area that later became Sierra Leone.

[1][2] Members of the expedition encountered "savage people, the greater part of whom were women, whose bodies were hairy, and whom our interpreters called Gorillae".

[5] Skins of gorillai women, brought back by Hanno, are reputed to have been kept at Carthage until Rome destroyed the city 350 years later at the end of the Punic Wars, 146 BC.

Those Pongos are neuer taken aliue, because they are so strong, that ten men cannot hold one of them... A century and a half after Battel's story was published, one writer called Radermacher wrote that "the large species, described by Buffon and other authors as of the size of a man, is held by many to be a Chimera.

"[7] The American physician and missionary Thomas Staughton Savage and naturalist Jeffries Wyman first described the western gorilla in 1847 from specimens obtained in Liberia.

The closest relatives of gorillas are the other two Homininae genera, chimpanzees and humans, all of them having diverged from a common ancestor about 7 million years ago.

The separate species and subspecies developed from a single type of gorilla during the Ice Age, when their forest habitats shrank and became isolated from each other.

Some variations that distinguish the classifications of gorilla include varying density, size, hair colour, length, culture, and facial widths.

Gorillas move around by knuckle-walking, although they sometimes walk upright for short distances, typically while carrying food or in defensive situations.

A 2018 study investigating the hand posture of 77 mountain gorillas at Bwindi Impenetrable National Park (8% of the population) found that knuckle walking was done only 60% of the time, and they also supported their weight on their fists, the backs of their hands/feet, and on their palms/soles (with the digits flexed).

[35] Studies of gorilla handedness have yielded varying results, with some arguing for no preference for either hand, and others right-hand dominance for the general population.

Due to novel sequences, though, it is different enough to not conform with the human ABO blood group system, into which the other great apes fit.

Mountain gorillas mostly eat foliage, such as leaves, stems, pith, and shoots, while fruit makes up a very small part of their diets.

[63] Male gorillas have weak social bonds, particularly in multiple-male groups with apparent dominance hierarchies and strong competition for mates.

Sounds classified as grunts and barks are heard most frequently while traveling, and indicate the whereabouts of individual group members.

Like the other great apes, gorillas can laugh, grieve, have "rich emotional lives", develop strong family bonds, make and use tools, and think about the past and future.

A female gorilla in the Nouabalé-Ndoki National Park in the Republic of Congo was recorded using a stick as if to gauge the depth of water whilst crossing a swamp.

[78] In September 2005, a two-and-a-half-year-old gorilla in the Republic of Congo was discovered using rocks to smash open palm nuts inside a game sanctuary.

Nonhuman great apes are endowed with semiprecision grips, and have been able to use both simple tools and even weapons, such as improvising a club from a convenient fallen branch.

American physician and missionary Thomas Staughton Savage obtained the first specimens (the skull and other bones) during his time in Liberia.

[82][83][84] The first systematic study was not conducted until the 1920s, when Carl Akeley of the American Museum of Natural History traveled to Africa to hunt for an animal to be shot and stuffed.

In the late 1920s and early 1930s, Robert Yerkes and his wife Ava helped further the study of gorillas when they sent Harold Bigham to Africa.

Years later, at the behest of Louis Leakey and the National Geographic, Dian Fossey conducted a much longer and more comprehensive study of the mountain gorilla.

[91] Gorillas became highly prized by western zoos since the 19th century, though the earliest attempts to keep them in captive facilities ended in their early death.

[93] Captive gorillas exhibit stereotypic behaviors, including eating disorders‍—‍such as regurgitation, reingestion and coprophagy‍—‍self-injurious or conspecific aggression, pacing, rocking, sucking of fingers or lip smacking, and overgrooming.

[96][97] The use of both internal and external privacy screens on exhibit windows has been shown to alleviate stresses from visual effects of high crowd densities, leading to decreased stereotypic behaviors in the gorillas.

[98] Enrichment modifications to feed and foraging, where clover-hay is added to an exhibit floor, decrease stereotypic activities while simultaneously increasing positive food-related behaviors.

In 2004, a population of several hundred gorillas in the Odzala National Park, Republic of Congo was essentially wiped out by the Ebola virus.

From the Central African Republic to Cameroon and Gabon, stories of reincarnations as gorillas, totems, and transformations similar to those recorded by Du Chaillu are still told in the 21st century.