Gorillas share between 98-99 % of their DNA with humans. They are peaceful, social animals. As human’s closest relative in evolutionary terms, they do not just share similar physical characteristics but also some of the advanced social behaviour and emotional intelligence that we possess. Fortunately gorillas have not ‘advanced’ enough to share most of the worst characteristics of humans in their impact on their environment, other species and each other.
Social structure
Gorillas are not territorial and live in stable social groups called troops. Social groups usually contain 3-15 gorillas consisting of a a dominant ‘silverback’ male(s), a few younger ‘black-back’ males and several adult females with young. The dominant male silverback has exclusive breeding rights and offers close protection to adult females and young within the troop. Adolescent males, as they mature, will more often break away to form their own troop with adolescent females. On occassion a maturing male silverback may challenge the dominant silverback’s authority to gain control of the troop. This is seldom succesful. They usually spend a period in relative isolation as they mature, until they become older and strong enough to challenge for a troop of their own (usually at 12+ years). Therefore another silverback from outside the immediate troop may challenge the existing dominant male.
The troop’s dominant silverback is typically more aggressive as it carries sole responsibility for the security and protection of all other troop members. During a gorillas lifetime, direct physical aggression is relatively rare as usually a display of chest thumping, teeth baring and the ripping up of vegetation is enough to deter any challenge or innapropriate behaviour. Indeed, a disappointed look from a dominant silverback will often quickly nip potential trouble in the bud! If provoked enough a silverback will charge but 99% of these charges are bluffs. Only rarely will gorillas come into physical conflict where they will use their enormous strength and huge canine teeth to inflict blows and bites.
Daily activity and social bonds
Given their size, and vegetarian diet, gorillas need to consume huge amounts of food to obtain the calories and nutrients they require. It is not surprising that they spend most of their waking hours foraging and eating (approximately 14 hours). The rest of the time is spent resting, although young gorillas will exert energy playing wrestling and chasing games. The area inhabited by a troop (their home range) can be anything from 4 to 25 km sq. However, they will only usually travel 0.5 to 1 km per day while foraging (unless food has become scarce in that area).
Gorillas construct beds to rest in. These are called nests. At the end of each day they will construct a new nest from twigs, branches and foliage to sleep in. These nests are usually built on the ground but sometimes constructed in elevated positions amongst tree branches. Young gorillas share a nest with an adult female for the first three years.
Resting gorillas perform social bonding rituals such as grooming. Greetings are made by touching noses and reassuring gestures are spread throughout the troop by touching and embracing.They communicate through a rich veriety of facial expressions, very much like humans. They also use sounds ranging from excited hoots and barks to contented clicks and rumbling purrs.