Although gorillas are generally quiet, they have a range of complex vocalisations which are used to communicate information in numerous contexts including teaching survival skills to young, searching for food, and during courtship, they are even capable of learning basic human sign language.
Gorillas live in fairly stable social groups comprising of one adult male usually referred to as the silverback (because of the silver hair on his back which signals full adulthood) and multiple females with juveniles and infants. When young males reach the age of 8-11 they will usually emigrate away and either join another group or form new groups.
Gorilla family groups each live within relatively small areas of land. Different groups can however occupy converging areas and co-exist peacefully.
In Mountain gorillas, the ‘belch vocalization’ is a contact call and sign of contentment while foraging. Most gorillas will use a low grumbling sound to both locate each other and as sign of contentment. Aggressive displays, such as the beating of chests and charging are quite rare but will be used by male gorillas as a warning if surprised or threatened.
Gorillas are generally calm and passive animals, however, the Silverback will defend his troop if he feels threatened. They are highly intelligent and have now been observed using tools in the wild.
Gorillas have been observed displaying emotions such as grief and compassion for other primates, including humans Scientist have shown that gorillas display individual personalities.
Gorillas will groom each other by combing each other with their fingers and teeth. This ‘social grooming’ is an important aspect of gorilla groups which helps to establish and reinforce social bonds.
Gorillas are mainly herbivorous, with the majority of their diet consisting of leaves, shoots and stems, some fruit and some small animal prey such as grubs, caterpillars, snails, termites and ants. Western Lowland gorilla diets have a much higher proportion of fruit.
Females will start giving birth at about 10 years old and will have offspring every 3-4 years. When in oestrus she will be able to conceive for only three days in the month.
Gorillas have a gestation period of nine months like humans, but babies usually weigh less than humans at approximately 4 pounds, their development is however roughly twice as fast.
Gorillas spend a good deal of their time on the ground rather than in the trees, and will make new nests on the ground each night.
Gorillas have hands and feet like humans including opposable thumbs and big toes. Some gorillas in captivity have learned to use sign language to communicate with humans. Gorillas live in small groups called troops or bands. In each troop there is one dominant male Silverback, some female gorillas, and their offspring.
Gorillas live around 35 years. They can live longer, up to 50 years, in captivity. They sleep at night in nests. Baby gorillas will stay in their mother’s nests until they are around 2 ½ years old.
Gorillas were seen for the first time using simple tools to perform tasks in the wild in 2005. They were observed using sticks to test the depth of muddy water and to cross swampy areas.