As a result, they must be tightly organized under strong leaders so they can avoid danger or defend themselves. Monkeys that live on the ground defend themselves chiefly by threatening their enemies. If a cheetah approaches a group of baboons, for example, the leaders of the group gather together to face the danger. Each male baboon shows his long canine teeth and barks. If these actions do not frighten the cheetah away, the baboons may attack.
Monkeys communicate with one another in various ways.
For example, a male rhesus monkey threatens members of its group by staring, opening its mouth and showing its teeth, bobbing its head, and slapping the ground with its hands. Social grooming helps maintain friendly relations between baboons. In grooming, one baboon carefully cleans the fur of another. Both animals seem to find satisfaction in this activity. Baboons spend several hours a day grooming.