ABSTRACT
This chapter covers three of the best-known primate genera of the Cebinae: the squirrel monkeys and the capuchins, recently divided into the genera Cebus, gracile capuchins, and Sapajus, robust capuchins. The descriptions of primate behavior are arranged under four headings: ecology, sociality, life cycle, and cognition. The morphology and behavior of the small-bodied squirrel monkeys is heavily affected by predation. They live in large troops with social organization that varies sharply across species. The fatted male is an unusual mating pattern. Capuchin monkeys adjust to a wide variety of environmental conditions, partly with the help of regular tool use. Grooming is important in their social behavior. Capuchins engage in a dramatic reunion display comparable to that of the spider monkeys. Capuchins have a very slow life history for their body size. The complexities of capuchin tool use indicate cognitive skills that are unusual among primates. Tufted and untufted capuchins differ in tool use and other important aspects of behavior.
