Dolphins (Tursiops truncatus) comprehend the referential character of the human pointing gesture.
The authors tested a dolphin's (Tursiops truncatus) understanding of human manual pointing gestures to 3 distal objects located to the left of, to the right of, or behind the dolphin. The human referred to an object through a direct point (Pd), a cross-body point (Px), or a familiar symbolic gesture (S). In Experiment 1, the dolphin responded correctly to 80% of Pds toward laterally placed objects but to only 40% of Pds to the object behind. Responding to objects behind improved to 88% in Experiment 2 after exaggerated pointing was briefly instituted. Spontaneous comprehension of Pxs also was demonstrated. In Experiment 3, the human produced a sequence of 2 Pds, 2 Pxs, 2 Ss, or all 2-way combinations of these 3 to direct the dolphin to take the object referenced second to the object referenced first. Accuracy ranged from 68% to 77% correct (chance = 17%). These results established that the dolphin understood the referential character of the human manual pointing gesture.
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Department of Psychology, University of Hawaii at Manoa, Honolulu, USA. lherman@hawaii.edu
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D000819:Animal Communication; D000818:Animals; D004289:Dolphins / Q000523:psychology*; D005868:Gestures; D006801:Humans; D008369:Manual Communication; D008606:Mental Processes; D013045:Species Specificity