One advantage of living in a social group is the opportunity to use information provided by other individuals. Social information
can be based on cues provided by a conspecific or even by a heterospecific individual (e.g., gaze direction, vocalizations,
pointing gestures). Although the use of human gaze and gestures has been extensively studied in primates, and is increasingly
studied in other mammals, there is no documentation of birds using these cues in a cooperative context. In this study, we
tested the ability of three African gray parrots to use different human cues (pointing and/or gazing) in an object-choice
task. We found that one subject spontaneously used the most salient pointing gesture (looking and steady pointing with hand
at about 20 cm from the baited box). The two others were also able to use this cue after 15 trials. None of the parrots spontaneously
used the steady gaze cues (combined head and eye orientation), but one learned to do so effectively after only 15 trials when
the distance between the head and the baited box was about 1 m. However, none of the parrots were able to use the momentary
pointing nor the distal pointing and gazing cues. These results are discussed in terms of sensitivity to joint attention as
a prerequisite to understand pointing gestures as it is to the referential use of labels.
Keywords African gray parrots (Psittacus erithacus) - Gaze - Heterospecific communication - Object-choice - Pointing - Referential signals