The bonobo communicate in a multitude of ways. They communicate through the use of their voice, actions, facial expressions, and symbols. How the bonobo communicate is one of the more controversial topics of bonobo behavior due to the difficulty in observing their communication and deciding whether the purpose of their behavior is actually to communicate with others.
Although some linguists and scientists are skeptical, Sue Savage, Professor at Georgia University and a researcher of the bonobo, believes that the bonobo do in fact communicate vocally but only do so in the trees to avoid predators when foraging on the ground. A more observable form of communication that the bonobo use is their facial expressions. The bonobo use a variety of facial expressions to communicate feelings such as submission, fear, dissatisfaction, and more.
The bonobo also communicate with each other through their actions. For example, mothers bend the wrists of their infants as a reassuring gesture. The bonobo have been known to use symbolic language to communicate, such as sign language, when taught by humans. In the wild, Sue Savage has cited the bonobo’s use of trampled plants and branches as symbolic communication to allow other members of a group to navigate forks in a trail and find the nesting location after a day of foraging.