Apes’ use of iconic cues in the object-choice task

Esther Herrmann, Alicia Melis, Michael Tomasello

Research output: Contribution to journalArticlepeer-review


In previous studies great apes have shown little ability to locate hidden food using a physical marker placed by a human directly on the target location. In this study, we hypothesized that the perceptual similarity between an iconic cue and the hidden reward (baited container) would help apes to infer the location of the food. In the first two experiments, we found that if an iconic cue is given in addition to a spatial/indexical cue – e.g., picture or replica of a banana placed on the target location – apes (chimpanzees, bonobos, orangutans, gorillas) as a group performed above chance. However, we also found in two further experiments that when iconic cues were given on their own without spatial/indexical information (iconic cue held up by human with no diagnostic spatial/indexical information), the apes were back to chance performance. Our overall conclusion is that although iconic information helps apes in the process of searching hidden food, the poor performance found in the last two experiments is due to apes' lack of understanding of the informative (cooperative) communicative intention of the experimenter.
Original languageEnglish
Pages (from-to)118-130
Number of pages13
JournalAnimal Cognition
Issue number2
Publication statusPublished - Apr 2006


  • Apes
  • Communicative intention
  • Iconic
  • Object-choice task

Cite this