Abstract
Bonobo tool-using behavior is rare, limited in variety and relatively simple in form. The tools of bonobos are almost always made of a crude branch with little processing and are used neither for getting food nor as a weapon but for improving "the quality of life" (rain hat, social communication etc.). The paucity is said to be influenced by the abundance and richness of the food resources, relieving them of the need to develop food processing tools. I agree with this explanation and propose another possibility. The chimpanzees' curiosity, high activity and aggressiveness to strangers and strange objects accelerated their development of tool-using behavior. In contrast, the mild and shy disposition of bonobos might have influenced the types of tools they developed.
