Facts About Gorillas

By Irina Bright.

This article is part of our Environment section

See the complete list of all our Articles about Rainforest Animals here.

We present some fascinating facts about gorillas.

gorilla mother baby congo Gorilla mother with her baby
Democratic Republic of the Congo
Photo: Johnny Chen
  • Gorillas live only in some tropical areas of Central Africa
  • Gorillas are the largest of all the great apes
  • Adult males may have a height of 1.7 metres and a weight of 135 – 220 kg in the wild
  • Adult females reach a height of 1.5 metres and a weight of 70 – 90 kg in the wild
  • Adults’ arms are 20% longer than legs; gorillas walk by using all four limbs, supported by the knuckles (“knuckle-walking”)
  • Gorillas’ skin and hair are black; they lack hair on the face, hands and feet
  • Silverback gorilla is a mature adult male with a patch of silver (grey) hair on his back
  • Gorillas are vegetarian; they eat fruits, leaves, shoots
  • Gorillas are important seed dispersers in the rainforest (they are the only known dispersing agents for some tree species); therefore, they play key ecological roles in their forest ecosystems (1)
  • They cannot swim but sometimes wade into swamps to feed on aquatic plants
  • Gorillas live in family groups of 6 to 30 individuals, which are led by one or two silverbacks; they are normally active during the day (diurnal)
  • A home range of each gorilla group is 2 – 40 km; but ranges of different groups may overlap
  • Gorillas build their own new nests every night using branches and foliage
  • They can use tools for problem-solving (for example, using a tree branch as a bridge to cross muddy ground)
  • Female gorillas give birth once every 4 years, normally to a single baby but occasionally to twins; the gestation period is 8.5 months
  • The repertoire of gorilla calls includes grunts, hoots, an alarm bark and the roar
  • The famous chest beating ritual is used for intimidating outsiders, communicating between the groups and maintaining the hierarchy within the group
  • In spite of all these physical expressions of emotion, gorillas are shy and un-aggressive unless improperly disturbed.

Written by:     Irina Bright
Original publication date:     2008
Republication date:     2020



Main Reference:
Gorilla (2008). In Encyclopedia Britannica. Retrieved January 16, 2008 from Britannica Online: http://www.britannica.com/eb/article-9037438

(1) Vedder, A. L., & Weber, W. (2000). Gorilla. In Endangered Animals: A Reference Guide to Conflicting Issues, Reading, R. P. & Miller, B. (Eds.), p. 131 . Westport, CT: Greenwood Press. Retrieved January 25, 2008 from Questia.com