Gorillas

The wild gorilla of equatorial Africa is the largest of the four great apes; the mountain subspecies was discovered in 1847 but first scientifically described in 1902. Until recently, this primate was thought to be a brutish and ferocious animal of the jungle. However, field studies have revealed that this huge pongid is shy, gentle, and introverted but curious, intelligent, and powerful.

In prehistoric times, wild gorillas ranged freely throughout central Africa. Today, however, this great ape is represented by only three geographically isolated subspecies: the lowland or valley gorilla of central West Africa, Gorilla gorilla gorilla; the slightly smaller highland or mountain gorilla of central East Africa,Gorilla gorilla beringei; and the lowland gorilla of East Africa, Gorilla gorilla graueri.The minor differences between the two major subspecies are that the mountain gorilla has longer hair (an adaptive advantage) and has a longer palate than the lowland gorilla and does not share its forest with chimpanzees.

Now a critically endangered species, the wild gorilla needs to be understood and appreciated in order to ensure both its protection and survival in captivity, as well as in its natural environment. It is estimated that fewer than 1,000 mountain gorillas inhabit the lush forest areas of central East Africa. Their ecological niche is gravely threatened by hunters, farmers, and poachers—thus the desperate plight of this mountain ape.

Source: © iStockphoto/Kevin Tate.

George B. Schaller, a zoologist, was the first scientist to seriously study the wild mountain gorillas in their natural habitat. His pioneering 20-month research project (1959–1960) remains a classic contribution to primate ethology. He has presented his important findings in two books: The Mountain Gorilla (1963) and The Year of the Gorilla (1965).

Gorillas are primarily terrestrial, quadrupedal climbers and knuckle walkers, living in the humid rain forests of Africa. In his extensive study of the mountain subspecies, Schaller concentrated on the ecology and general behavior of this remarkable great ape. His 466 hours of direct observation were made from the safety and viewing advantage of trees. Schaller was able to watch free-living gorillas wander through the dense jungle, forage on succulent herbs and vines (they prefer young secondary forest growth), groom and play, and build nests in the trees or on the ground. The zoologist observed no tool use, no meat eating, and no drinking of water. Both vocalizations and sexual behavior were infrequent. Of particular interest, however, is the gorilla's chest-slapping behavior—an elaborate sequence of nine distinct acts by a provoked gorilla in order to frighten away a threatening intruder, thereby preventing physical contact.

Despite his dedicated study of this wild ape for nearly 2 years, Schaller never made physical contact with these mountain gorillas. Yet this incredible feat was later accomplished by the remarkable primatologist Dian Fossey.

During 1967–1985, anthropologist Fossey lived among the wild highland gorillas of the Virunga Volcanoes in central East Africa. (The lowland or valley gorillas of central West Africa still await rigorous study.) Her research camp, Karisoke, was located in the ancient rain forest of Mt. Vasokie—a tropical world of jungle, fog, and mist in Rwanda near Zaire. Encouraged by anthropologist Louis S. B. Leakey,Fossey had followed gorilla groups on the ground in order to observe them at close range during their leisurely day-long search for food. Fossey was very successful in establishing a rapport with [Page 1103]these great apes; she patiently learned to imitate their feeding methods, general sounds, and basic gestures. As a result of her relentless efforts, these curious and gentle giants of the primate world had slowly accepted the anthropologist's presence. This acceptance allowed her to examine the uninhibited behavior of mountain gorillas under normal conditions in their natural range.

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