Social bonds affect anti-predator behaviour in a tolerant species of macaque,Macaca nigra

Bridget M Waller,Christof Neumann,Jérôme Micheletta,Maria R Panggur,Muhammad Agil,Antje Engelhardt,Julie Duboscq

doi:10.1098/rspb.2012.1470

Abstract

Enduring positive social bonds between individuals are crucial for humans' health and well being. Similar bonds can be found in a wide range of taxa, revealing the evolutionary origins of humans' social bonds. Evidence suggests that these strong social bonds can function to buffer the negative effects of living in groups, but it is not known whether they also function to minimize predation risk. Here, we show that crested macaques (Macaca nigra) react more strongly to playbacks of recruitment alarm calls (i.e. calls signalling the presence of a predator and eliciting cooperative mobbing behaviour) if they were produced by an individual with whom they share a strong social bond. Dominance relationships between caller and listener had no effect on the reaction of the listener. Thus, strong social bonds may improve the coordination and efficiency of cooperative defence against predators, and therefore increase chances of survival. This result broadens our understanding of the evolution and function of social bonds by highlighting their importance in the anti-predator context.

Highlights

The existence of strong enduring social bonds between individuals is a central feature of human societies
We show that crested macaques (Macaca nigra) react more strongly to playbacks of recruitment alarm calls if they were produced by an individual with whom they share a strong social bond
Our results show that female crested macaques attend more to the alarm calls of affiliates compared with nonaffiliates, highlighting the importance of social bonds in the life-threatening context of predator deterrence

Summary

Introduction

The existence of strong enduring social bonds between individuals is a central feature of human societies. Studies in a wide range of taxa, from mice to non-human primates, show that these bonds are not uniquely human, which allows us to investigate the evolution and function of such strong positive relationships [4,5]. Data from non-human animals suggest that social bonds provide fitness benefits in the within-group social context, but whether they provides advantages in immediate survival contexts such as defence against predators, remains unknown [4]. The aim of this study was to investigate the role that social bonds may have in the context of anti-predator behaviour using field playback experiments.

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Conclusion