Social influences on visual attention in primates

  • Lisa Lane

Student thesis: Doctoral Thesis


Studies of visual attention in primates have generally focused on anti-predatory functions of vigilance, and likewise, social attention is commonly associated with protecting against threat. However, little research has tested whether threat protection provides the best representation of social visual attention in primate groups. Moreover, social monitoring hasrarely been considered as a function of social relationships and whether affiliation is important.
This thesis is comprised of a series of studies examining social monitoring in captive chimpanzees,orang-utans and siamangs; and in free-ranging chacma baboons and ring-tailed lemurs.Particular emphasis is placed on considering social monitoring as a dyadic social interaction, involving both an initiator and recipient of attention. This 'social' approach to social monitoring uses dyadic social relationships within the group and attributes of the initiator and recipient to interpret visual attention.
The effects of dyadic relationship quality on visual social monitoring were examined in all the study species. Indices of the strength of affiliative relationships were used to provide a quantitative measure of social relationships and categorise dyads as friends or non-friends. In contrast to standard interpretations of social monitoring, affiliative relationships have a significant influence on the distribution of social monitoring in some primate groups.
Social referencing, a complementary aspect of visual social attention, was also explored in orang-utans using visual responses to naturally occurring events and orang-utan playback vocalisations. Using this novel approach, this is the first study that documents social referencing in adult orang-utans and that biological relevance and ambiguity are important forseeking reference from conspecifics.
The final section of this thesis considers the visual budgets of the study species, a multi-faceted basisof vigilance in primates, and asks whether the frequency of social monitoring in primate groups can be predicted from a number of variables. Interactive effects of species, context, attention types and targets revealed the complex nature of visua lattention in primate groups. Social variables contributed strongly to the variability in primate social monitoring.
The findings indicate that visual attention reflects social relationships in primate groups. The predominantly affiliative nature of primate social interactions suggests the influence of threat protection on social attention has been overemphasised. Accordingly, visual social attention plays an important role in social interactions, permitting individuals to monitor group dynamics, seek information and respond to changes appropriately.
Date of AwardSept 2008
Original languageEnglish
Awarding Institution
  • University of Portsmouth
SupervisorKim A. Bard (Supervisor) & Alan Costall (Supervisor)

Cite this