Problem-solving strategies and hand preferences for a multicomponent task by tufted capuchins (Cebus apella)

We examined hand preferences in 23 tufted capuchins (Cebus apella) in 2 tasks requiring the lid of a box to be lifted before taking out a peanut. The first task, Box 1, could entail either two or three problem-solving acts, with the three-act solution involving bimanual coordination for food retrieval. The second task, Box 2, involved only the three-act solution. The results indicated that the types of solution employed to perform the task influenced capuchins' hand preferences. In the two-act solution, capuchins exhibited a significant right-hand bias for the final one-handed reaching action, but not for the initial lid lifting action. In contrast, in the three-act solution, no significant asymmetry emerged for any act. We noted a significant effect of subject's sex on the strength of laterality, with males being more strongly lateralized than females. We discuss results in the light of recent models of primate laterality.