A key skill in early human development is the ability to comprehend communicative intentions as expressed in both nonlinguistic gestures and language. In the current studies, we confronted domestic dogs (some of whom knew many human "words") with a task in which they had to infer the intended referent of a human's communicative act via iconic…

G. Gergely, H. Bekkering, and I. Kiraly (2002) showed that 14-month-old infants imitate rationally, copying an adult's unusual action more often when it was freely chosen than when it was forced by some constraint. This suggests that infants understand others' intentions as rational choices of action plans. It is important to test whether apes…

Human infants imitate others' actions "rationally": they copy a demonstrator's action when that action is freely chosen, but less when it is forced by some constraint (Gergely, Bekkering & Kiraly, 2002). We investigated whether enculturated chimpanzees (Pan troglodytes) also imitate rationally. Using Gergely and colleagues' (2002) basic procedure,…

This study investigated 2-year-olds' understanding of others' intentions in a social learning context. After seeing a demonstration of how to open a box, children in two "No Prior Intention" conditions were less likely than those in "Prior Intention" conditions to open the box themselves when the adult unsuccessfully tried to open it. Results…

Infants experienced a female adult handing them toys. Sometimes, however, the transaction failed, either because the adult was in various ways unwilling to give the toy (e.g., she teased the child with it or played with it herself) or else because she was unable to give it (e.g., she accidentally dropped it). Infants at 9, 12, and 18 months of age…

Understanding the intentional actions of others is a fundamental part of human social cognition and behavior. An important question is therefore whether other animal species, especially our nearest relatives the chimpanzees, also understand the intentional actions of others. Here we show that chimpanzees spontaneously (without training) behave…