Chase Braun
Pronouns: he/him
Research Mentor(s): Alexandra Rosati
Research Mentor School/College/Department: Psychology / LSA
Program: UROP
Session: Session 5 (2:40pm – 3:30pm)
Authors: Chase Braun, Averill Cantwell, Alexandra Rosati
Abstract
An important method of acquiring information about the environment is gaze following, looking in the same direction as another individual. This is an important foundational sociocognitive skill, which may scaffold more complex abilities like theory of mind. In other primate species, factors such as age, sex, and social rank affect how likely an individual is to follow another’s gaze. For example, females and younger individuals generally exhibit a higher propensity to follow other’s gaze, whereas low-ranking individuals follow the gaze of more group members. However, research in this area is still limited to a small number of primate species. Here, we investigated how these factors contribute to differences in our closest living primate relative’s gaze following abilities. To do so, we tested 90 chimpanzees (Pan troglodytes) living in two African sanctuaries on a task that involved following a human experimenter’s gaze up. This included six test trials where the experimenter looked up, and a control trial where she looked down. We analyzed the effects of age, sex, and social rank on responses. Based on past results in humans and macaques, we hypothesized that gaze following will decrease as age increases, and that females will gaze follow more than males. In addition, we tested two hypotheses for the effects of social rank: (1) strong social relationships and vigilance to threats may cause higher-ranked chimpanzees to increase gaze following, or (2) low-ranking chimpanzees may pay more attention to social cues from routinely facing social challenges. Contrasting prior work, no significant effects of age, sex, or social rank alone on gaze following were found in this sample. However, there was a significant interaction between sex and rank, with middle-ranking males following gaze less than middle-ranking females. We discuss how our findings broaden our understanding of individual differences in primate gaze tasks, and the importance of investigating within-species differences in core sociocognitive skills like gaze following, as this skill is essential for humans and other animals to seek information about their environment.
