Gestural acquisition in great apes: the Social Negotiation Hypothesis

Simone Pika,Marlen Fröhlich

doi:10.1007/s10071-017-1159-6

Abstract

Scientific interest in the acquisition of gestural signalling dates back to the heroic figure of Charles Darwin. More than a hundred years later, we still know relatively little about the underlying evolutionary and developmental pathways involved. Here, we shed new light on this topic by providing the first systematic, quantitative comparison of gestural development in two different chimpanzee (Pan troglodytes verus and Pan troglodytes schweinfurthii) subspecies and communities living in their natural environments. We conclude that the three most predominant perspectives on gestural acquisition—Phylogenetic Ritualization, Social Transmission via Imitation, and Ontogenetic Ritualization—do not satisfactorily explain our current findings on gestural interactions in chimpanzees in the wild. In contrast, we argue that the role of interactional experience and social exposure on gestural acquisition and communicative development has been strongly underestimated. We introduce the revised Social Negotiation Hypothesis and conclude with a brief set of empirical desiderata for instigating more research into this intriguing research domain.

Highlights

Language, more than anything else, distinguishes us from the rest of the animal kingdom (Knight et al 2000)
Since they seem to fulfil different functions and convey different meanings in other wild chimpanzee communities, they strengthen our argumentation that social negotiation plays a crucial role in enabling and transmitting communicative meaning—and thereby possibly communicative culture—within great ape communities
Our results suggest that the role of interactional experience and social exposure on gestural acquisition and communicative development of chimpanzees has been severely underestimated

Summary

Introduction

More than anything else, distinguishes us from the rest of the animal kingdom (Knight et al 2000). Loud and exaggerated scratching gestures— directed scratches—used in the chimpanzee community Ngogo to negotiate role reversal and cooperation during grooming (Pika 2014; Pika and Mitani 2006) are characterized by too many variations in size, scope, location, and orientation of gestures to qualify as constant in form over time Since they seem to fulfil different functions and convey different meanings in other wild chimpanzee communities (e.g. they have been reported at Gombe to be produced as one-way gestures by mothers towards their infants to solicit leaving a location together; Goodall 1986), they strengthen our argumentation that social negotiation plays a crucial role in enabling and transmitting communicative meaning—and thereby possibly communicative culture—within great ape communities (see van Leeuwen et al 2012). The vocal-gesture shift may be selected for in evolutionary urgent contexts (e.g. hunting and patrol in chimpanzees, Mitani 2009), where predators or members of neighbouring groups severely impact upon individuals’ survival and reproductive success

Conclusions

Compliance with ethical standards