Orangutans’ Comprehension of Zoo Keepers’ Communicative Signals
Simple SummaryMost modern zoos work towards the promotion of captive animals’ welfare. One way of achieving this is by encouraging cooperative interactions between keepers and zoo animals, for instance during sessions of conditioning training. To be most effective, communication between them should use those channels that are most useful to the animals. In this study, we asked whether captive orangutans were capable of understanding keepers’ instructions when they were employing words only, gazes only, gestures only, or all signal types combined. Our results indicate that the subjects only need gestures to respond to the keepers’ instructions. In two other experiments, we examined why gestures were so effective. One hypothesis was that they resemble what they refer to. However, we found no indication that gestures providing iconicity or even pointing could help orangutans acquire associations between a new gesture and referent. Our results suggest that, among human communicative signals, captive orangutans would prefer gestures. Why this is the case should be the focus of future research.
AbstractZoological institutions often encourage cooperative interactions between keepers and animals so as to promote animals’ welfare. One useful technique has been conditioning training, whereby animals learn to respond to keepers’ requests, which facilitates a number of, otherwise sensitive, daily routines. As various media have been used to convey keepers’ instructions, the question remains of which modality is best to promote mutual understanding. Here, we explored this question with two captive female orangutans. In the first experiment, we compared orangutans’ understanding of previously acquired instructions when those were performed with verbal signals only, gazes only, gestures only, and when all those modalities were combined. Our results showed that gestures were sufficient for successful comprehension by these two apes. In the second experiment, we asked whether this preference could be driven by the non-arbitrary relationship that gestures bear to what they refer to, through iconicity or pointing. Our results revealed that neither iconicity nor pointing helped the subjects comprehend the keepers’ instructions. Our results indicate a preference for instructions given through gestural signals in two captive female orangutans, although its cause remains elusive. Future practice may encourage the use of gestures in communication between keepers and orangutans in general or potentially other animals. View Full-Text
Supplementary File 1:
Table S1: List of requests conventionally used in medical training, Video S1: Video extracts of Experiment 1 depicting orangutan Theodora in three trials of the Words condition and orangutan Tamü in six trials of the Gestures condition (DOI: 10.5281/zenodo.3235831)
Externally hosted supplementary file 1
Description: Table S1: list of requests conventionally used in medical training, Video S1: Video extracts of experiment 1 depicting orangutan Theodora in 3 trials of condition Words and orangutan Tamü in 6 trials of condition Gestures. Other Supplementary materials: full dataset of experiment 1 (excel sheet OOdata1), Experiment 2 A (excel sheet OOdata2A), experiment 2 B (excel sheet OOdata2B) and analysis script available at URL https://osf.io/hjcfz/.
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Dezecache, G.; Bourgeois, A.; Bazin, C.; Schlenker, P.; Chemla, E.; Maille, A. Orangutans’ Comprehension of Zoo Keepers’ Communicative Signals. Animals 2019, 9, 300.
Dezecache G, Bourgeois A, Bazin C, Schlenker P, Chemla E, Maille A. Orangutans’ Comprehension of Zoo Keepers’ Communicative Signals. Animals. 2019; 9(6):300.Chicago/Turabian Style
Dezecache, Guillaume; Bourgeois, Aude; Bazin, Christophe; Schlenker, Philippe; Chemla, Emmanuel; Maille, Audrey. 2019. "Orangutans’ Comprehension of Zoo Keepers’ Communicative Signals." Animals 9, no. 6: 300.
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