The present study aims to investigate the interplay of verbal and nonverbal communication with respect to infants' perception of pointing gestures. Infants were presented with still images of pointing hands (cue) in combination with an acoustic stimulus. The communicative content of this acoustic stimulus was varied from being human and communicative to artificial. Saccadic reaction times (SRTs) from the cue to a peripheral target were measured as an indicator of the modulation of covert attention. A significant cueing effect (facilitated SRTs for congruent compared with incongruent trials) was only present in a condition with additional communicative and referential speech. In addition, the size of the cueing effect increased the more human and communicative the acoustic stimulus was. This indicates a beneficial effect of verbal communication on the perception of nonverbal communicative pointing gestures, emphasizing the important role of verbal communication in facilitating social understanding across domains. These findings additionally suggest that human and communicative (ostensive) signals are not qualitatively different from other less social signals but just quantitatively the most attention grabbing among a number of other signals.

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a b s t r a c tThe age at which young children show an aversion to inequitable resource distributions, especially those favoring themselves, is unclear. It is also unclear whether great apes, as humans' nearest evolutionary relatives, have an aversion to inequitable resource distributions at all. Using a common methodology across species and child ages, the current two studies found that 3-and 4-yearold children (N = 64) not only objected when they received less than a collaborative partner but also sacrificed to equalize when they received more. They did neither of these things in a nonsocial situation, demonstrating the fundamental role of social comparison. In contrast, chimpanzees (N = 9) showed no aversion to inequitable distributions, only a concern for maximizing their own resources, with no differences between social and nonsocial conditions. These results underscore the unique importance for humans, even early in ontogeny, for treating others fairly, presumably as a way of becoming a cooperative member of one's cultural group.