Adebola Ogunneye
Research Mentor: Alexandra Rosati
Mentor Department: Psychology, LSA
Author(s): Adebola Ogunneye, Rosa Muñoz, Alexandra Rosati
Session: Session 3 (11:00 AM – 11:50 AM)
Presentation Type: Poster 100
Abstract
Ownership is often considered a uniquely human behavior, yet evidence from nonhuman animals suggests the presence of behavioral precursors. This study examines how rhesus macaques (Macaca mulatta), a species with many socio-cognitive similarities to humans, establish and respect possession of a valuable resource. We tested 53 semi-free-ranging adult rhesus monkeys from the Cayo Santiago Field Station in Puerto Rico. In Study 1, we measured a monkey’s ability to establish exclusive possession of a valuable resource within their natural social group. In Study 2, we conducted a dyadic version of the task where we measured the monkey’s ability to ‘respect’ (i.e., not interfere) the possession of another monkey. We hypothesized that proxies of social status would predict performance in the establishment of possession task (Study 1), such that males would be more likely to establish possession than females, but would not predict performance in the respect of possession task (Study 2). In Study 1, we found that males and females are equally likely to establish possession [X²=2.64, df=1, p=0.10] but males did maintain initial possession for longer periods than females [X²=13.58, df =1, p<0.01]. In both sexes, displacement (females: 27%, males: 36%) was the most common form of possession termination, followed by voluntary terminations (females: 27%, males: 23%). In Study 2, males were generally less likely to respect the possessions of others, and possession was respected more frequently by the focal monkey when their partner was male [X²=5.99, df=1, p<0.05]. We did not observe a clear relationship between an individual’s ability to establish possession and their likelihood of respecting another’s possession. Together, these findings demonstrate that rhesus monkeys exhibit socially structured responses to possession, with sex-related differences influencing how possession is maintained and respected.
