Pointing by apes is near-ubiquitous in captivity, yet rare in their natural habitats. This has implications for understanding both the ontogeny and heritability of pointing, conceived as a behavioral phenotype. The data suggest that the cognitive capacity for manual deixis was possessed by the last common ancestor of humans and the great apes. In this review, nonverbal reference is distinguished from symbolic reference. An operational definition of intentional communication is delineated, citing published or forthcoming examples for each of the defining (...) criteria from studies of manual gestures in apes. Claims that chimpanzees do not point amongst themselves or do not gesture declaratively are refuted with published examples. Links between pointing and cognitive milestones in other domains relating means to ends are discussed. Finally, an evolutionary scenario of pointing as an adaptation to changes in hominid development is briefly sketched. (shrink)

Henrich et al. convincingly caution against the overgeneralization of findings from particular human populations, but fail to apply their own compelling reasoning to our nearest living relatives, the great apes. Here we argue that rearing history is every bit as important for understanding cognition in other species as it is in humans.

Corballis suggests that apes lack voluntary control over their vocal production. However, recent evidence implicates voluntary control of vocalizations in apes, which suggests that intentional control of vocal communication predates the hominid-pongid split. Furthermore, the ease with which apes in captivity manipulate the visual attention of observers implies a common cognitive basis for joint attention in humans and apes.

Comparative and developmental psychology are engaged in a search for the evolutionary and developmental origins of the perceptions of “intentions” and “desires,” and of epistemic states such as “ignorance” and “false belief.” Shanker & King (S&K) remind us that these are merely words to describe public events: All organisms that can discriminate states of “knowledge” in others have learned to do this through observation of publicly available information.

That organisms have a concept “see” does not necessarily entail that they attribute knowledge to others or predict others' behaviors on the basis of inferred mental states. An alternative experimental protocol is proposed in which accurate prediction of the location of an experimenters' impending appearance is contingent upon subjects' attribution of knowledge to the experimenter.