Spontaneous cross-species imitation in interactions between chimpanzees and zoo visitors

Tomas Persson,Elainie Alenkær Madsen,Gabriela-Alina Sauciuc

doi:10.1007/s10329-017-0624-9

Abstract

Imitation is a cornerstone of human development, serving both a cognitive function (e.g. in the acquisition and transmission of skills and knowledge) and a social–communicative function, whereby the imitation of familiar actions serves to maintain social interaction and promote prosociality. In nonhuman primates, this latter function is poorly understood, or even claimed to be absent. In this observational study, we documented interactions between chimpanzees and zoo visitors and found that the two species imitated each other at a similar rate, corresponding to almost 10% of all produced actions. Imitation appeared to accomplish a social–communicative function, as cross-species interactions that contained imitative actions lasted significantly longer than interactions without imitation. In both species, physical proximity promoted cross-species imitation. Overall, imitative precision was higher among visitors than among chimpanzees, but this difference vanished in proximity contexts, i.e. in the indoor environment. Four of five chimpanzees produced imitations; three of them exhibited comparable imitation rates, despite large individual differences in level of cross-species interactivity. We also found that chimpanzees evidenced imitation recognition, yet only when visitors imitated their actions (as opposed to postures). Imitation recognition was expressed by returned imitation in 36% of the cases, and all four imitating chimpanzees engaged in so-called imitative games. Previously regarded as unique to early human socialization, such games serve to maintain social engagement. The results presented here indicate that nonhuman apes exhibit spontaneous imitation that can accomplish a communicative function. The study raises a number of novel questions for imitation research and highlights the imitation of familiar behaviours as a relevant—yet thus far understudied—research topic.

Highlights

By enabling quick and high-fidelity social learning, imitation is regarded as a key mechanism for mediating the cross-generational transfer of knowledge and skills, (e.g. Nielsen 2009)
Imitation is a cornerstone of human development, serving both a cognitive function and a social–communicative function, whereby the imitation of familiar actions serves to maintain social interaction and promote prosociality
In the present study we focus on this social–communicative function of imitation, which, unlike imitation learning is less investigated in nonhuman primates1

Summary

Introduction

By enabling quick and high-fidelity social learning, imitation is regarded as a key mechanism for mediating the cross-generational transfer of knowledge and skills, (e.g. Nielsen 2009). In the present study we focus on this social–communicative function of imitation, which, unlike imitation learning is less investigated in nonhuman primates. Primates (2018) 59:19–29 imitation’ compared to children (Nielsen 2009; Carpenter and Call 2009) The latter captures the fact that children— but not chimpanzees—show a propensity for slavishly copying actions over outcomes, even when the demonstrated actions are irrelevant for achieving a demonstrated outcome. These differences, it has been argued, are to be attributed to the fact that a motivation to be social and promote shared experience lies behind children’s imitative behaviour

Methods

Results

Conclusion