There was a time when gorillas were considered to be fearsome creatures, but various studies conducted on them in the past few years have generally recognised them as gentle apes. Living in close family groups, the dominant males are much bigger than the females. Besides keeping the family united, these strict 'disciplinarians and protectors' also settle quarrels in the group and discipline youngsters by adopting rigid stances and simply glaring at the offenders. While roaming in the jungle if they find a place where there is a good supply of food, the members start with a meal, watched over by the leader. When the latter feeds the older sons stand guard.

Unlike other primates, gorillas make elaborate preparations before going to sleep. They make 'beds' by twisting together braches in trees and covering the framework with grass and leaves. When it comes to sleeping, baby gorillas are placed higher up on the branches, while the females and young males sleep on the lower branches.

As night falls, the father of the family drives everybody, including his mates and the younger members, up to 'bed' and then he settles himself down on the ground with his back against the tree and his arms folded across his chest. There he sits the whole night dozing, but ever on the alert against any approaching danger.

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Contrary to the popular impression that gorillas are bellicose creatures, ready to attack anybody who crosses their path, they are rather timid and avoid fight whenever possible. If any predator suddenly comes upon the family, the first thing the leader does is to send all the members to a safe place. After that he starts his great bluffing performance. He starts with hooting and snatching branches from the trees. Suddenly, he rises on his hind legs and throws the branches around. Next, he beats his chest with his forepaws, kicks one leg in the air and lets out a mighty roar. If that does not scare off the intruder, he takes a short run sideways, thumps the ground with the palm of his hand and charges. But it is all bluff. Provided the intruder does not attempt to attack him, the gorilla stands still for a moment, then turns and walks away peacefully.

It is only when this bluffing exercise fails that the gorillas attack. Sometimes foolhardy and inexperienced big cats still try to invade the ape's domain, ignoring his performance. That is when he really becomes nasty and many a time intruders have been torn to pieces by the great ape's mighty arms and formidable teeth.

Besides predators, the presence of rival males also arouses aggression in these animals; here too the defender first tries to avoid actual combat and attempts to awe his opponent into submission. Belligerence is important in the breeding success of males, since the female's choice of mate depends largely on his strength and ability to protect both herself and her offspring.

A group of gorillas usually consists of three to four females and their young ones led by one enormous mature adult male with a silver-grey saddle of hair on his back, because of which he is also known as silverback. Females in the group are unrelated among themselves. Hence the social structure is entirely one formed between the females and the silverback. Since the females prefer to mate with one male at a time, males face intense competition among themselves. Male gorillas become sexually mature around the age of eleven. This is the time when their breaking off with the group starts. In the initial years of reaching sexual maturity they become peripheral males, spending less time with their family, but staying within the sight of the group.