Using Cross Correlations to Investigate How Chimpanzees (Pan troglodytes) Use Conspecific Gaze Cues to Extract and Exploit Information in a Foraging Competition

• Type of Material: Article
• Authors: Katie Hall, University of St. Andrews; Mike W. Oram, University of St. Andrews; Matthew W. Campbell, Emory University; Timothy M. Eppley, Emory University; Richard W. Byrne, University of St. Andrews; Frans B M De Waal, Emory University
• Language: English
• Date: 2014-10-01
• Publisher: Wiley: 12 months
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2014 Wiley Periodicals, Inc.
• Final Published Version (URL): http://dx.doi.org/10.1002/ajp.22279
• Title of Journal or Parent Work: American Journal of Primatology
• ISSN: 0275-2565
• Volume: 76
• Issue: 10
• Start Page: 932
• End Page: 941
• Grant/Funding Information: This project was supported by the Living Links Center of the Yerkes National Primate Research Center and Emory University College funds.; KH was supported by the Janet T. Anderson Trust, the Scottish Overseas Research Student Award Scheme, and a studentship from the University of St Andrews School of Psychology.; The YNPRC receives support from NIH’s National Center for Research Resources P51RR165 (currently supported by the Office of Research Infrastructure Programs/OD P51OD11132).; MWC was supported by the FIRST program (NIH/NIGMS (USA) IRACDA grant number K12 GM000680).
• Keywords: MACAQUES MACACA-TONKEANA; PIGS; introduction; social manipulation; Zoology; cross correlation; tactics of competition; DOMINANCE; GREAT APES; HIERARCHY; SYNCHRONY; EYE; KNOWLEDGE; BEHAVIOR; ATTENTION; Life Sciences & Biomedicine; Science & Technology; gaze following
• Research Categories: Psychology, Behavioral; Biology, Zoology

Abstract

In a dyadic informed forager task, chimpanzees (Pan troglodytes) are known to exploit the knowledge of informed subordinates; however, the behavioral mechanisms they employ are unknown. It is tempting to interpret outcome measures, such as which individual obtained the food, in a cognitively richer way than the outcomes may justify. We employed a different approach from prior research, asking how chimpanzees compete by maneuvering around each other, whether they use gaze cues to acquire information from others, and what information they use in moment-to-moment decision-making. We used cross correlations, which plot the correlation between two variables as a function of time, systematically to examine chimpanzee interactions in a series of dyadic informed forager contests. We used cross correlations as a "proof of concept" so as to determine whether the target actions were contingent on, or occurred in a time-locked pattern relative to, the referent actions. A subordinate individual was given privileged knowledge of food location. As expected, an ignorant dominant followed the informed subordinate's movement in the enclosure. The dominant also followed the subordinate's gaze direction: after she looked at the subordinate, she was more likely to gaze toward this same direction within one second. In contrast, the subordinate only occasionally followed the dominant's movement and gaze. The dominant also changed her own direction of movement to converge on the location to which the subordinate directed her gaze and movement. Cross correlation proves an effective technique for charting contingencies in social interactions, an important step in understanding the use of cognition in natural situations.