Why Does a Gorilla Beat Its Chest?
A male gorilla beats his chest as a means of emphasizing his authority over the rest of the troop, or to frighten away intruders.
It’s basically saying, “I’m a big, bad guy and you’d better steer clear of me if you know what’s good for you. I’d rather not engage in fighting, so I’m sending you this message so you’ll leave and we can avoid a fight.”
When the leading male feels it is necessary to enforce discipline, he stands erect, hooting and roaring and beating his chest. Then he tears noisily through the brush, pulling up and hurling vegetation.
This display, however, is hardly ever more than a threat. Even a charging gorilla will almost always stop short of an actual attack.
Although it’s not only to do with showing control and aggression. A gorilla also beats his chest, asking his family to obey. For example, if a male gorilla beats his chest and walks off, he wants the family to follow him.
Contrary to belief, a gorilla does not beat his chest as a sign of victory after a battle.