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Western lowland gorilla

Scientific name: Gorilla gorilla gorilla

CLASS: Mammalia
ORDER: Primates
FAMILY: Hominida

STATISTICS: Weight: 150 - 450 lbs., Height: up to 6 ft.

The lowland gorilla has a very muscular neck, a wide chest, thick eye ridges, flared nostrils, and very nimble hands and feet. Its body is covered in coarse gray or black hair except for its face, hands and feet. In comparison to the mountain gorilla, the western lowland gorilla has a larger, wider skull and shorter hair. Also, the big toe of the western lowland gorilla is spread far apart from the alignment of his other four toes compared to the alignment in mountain gorillas.

African countries of Cameroon, People’s Republic of Congo, Gabon, Central African Republic, and Equatorial Guinea

African tropical forests

Lowland gorillas are very social creatures, living in family groups called troops. The troops are led by the oldest, dominate male, who decides when to wake up, eat, and go to bed. Some males become solitary after they have reached adulthood. Nevertheless, a new troop can be easily formed when one or more non-related females join a lone male. Males fight for dominance by vocalizing, thumping their chests, and occasionally charging at each other. However, these displays very rarely become violent.

The western lowland gorilla is characterized as a quiet, peaceful, and a very non- aggressive animal. It rarely attacks unless provoked. However, once provoked, an adult male protecting his group will attempt to intimidate his aggressor by standing on his legs and slapping his chest with cupped hands while vocalizing. If this elaborate display is unsuccessful and the intruder persists, the male will rear his head back violently several times. Then he will drop on all fours and charge toward the intruder. In general, when a gorilla charges he does not hit the intruder. Instead, he merely passes them by. This demonstration of aggression maintains order among separate troops and reduces the possibility of injury. Overlapping troops in the wild rarely have confrontations.

Gorillas are most active in the morning. They wake up just after sunrise to search for food, and eat for several hours. During midday, adults usually nap while the young wrestle and play games that may resemble games played by human children, such as follow the leader. After their midday nap, gorillas search for food again. Before dusk each gorilla makes its own nest bed on the ground. Gorillas can see, hear and smell as well as humans. Their arms are longer than their legs and their thumbs are longer than their fingers. These adaptations assist with locomotion.

After a gestation period of eight to nine months, a baby gorilla is born that is almost as helpless as its human counterparts. It matures at approximately twice the rate of human babies, and within three months the gorilla is able to ride and cling to its mother’s back. The baby gorilla continues to do this until three to four years later, when it reaches maturity. Female gorillas become sexually mature between the ages of six to nine years old, whereas the males don’t mature until they are nine to 12 years old. Breeding occurs year-round, and a successful female can have from three to six babies over the course of her lifetime.

Prey to leopard and man
Predator to none

Fruit, shoots, bulbs, tree bark, leaves

Listed as Critically Endangered by IUCN due to habitat destruction, big game hunting, and poaching.


  • In a study done through Stanford University in the 1970s, Francine Patterson was able to teach a female lowland gorilla several hundred words in sign language.
  • The word “gorilla” means “hairy person” in an African language.


  1. Novak, Ronald M. Walker’s Mammals of the World. Vol. I. Baltimore, Maryland. The Johns Hopkins University Press. 1991
  2. Eastern Lowland Gorilla. The Big Zoo. 2003.
  3. CITES. June 2008
  4. IUCN Red List of Threatened Species. June 2008.

  Published: October 2008

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