Date of Thesis

Spring 2019

Thesis Type

Masters Thesis

Degree Type

Master of Science


Animal Behavior

First Advisor

Regina P. Gazes


brown capuchins (Cebus [Sapajus] apella), primate behavior, social behavior, cognition, learning


The cognitive demand on animals to learn, maintain, and remember the complexities of social relationships is higher for individuals who live more complex social lives. Previous research has suggested that both across and within species, as social complexity increases so does the ability to flexibly learn and manipulate information. Elucidating the relationship between social complexity and cognition is therefore essential to understanding how evolutionary pressures have shaped cognitive development. In this study, I determined if there was a relationship between social complexity and cognitive performance on two standard tests of learning, associative learning and reversal learning. Subjects were 16 members of a socially housed group of brown capuchin monkeys (Cebus [Sapajus] apella). Each subject completed up to five rounds of testing on a series of associative learning and reversal learning tasks. A general learning score was extracted from a principal component analysis on cognitive testing performance across the two tasks. Behavioral observations of affiliative and grooming interactions were used to characterize the complexity of each monkey’s social life in the social network of the group. Generalized linear models revealed that learning performance was best explained by centrality in the grooming social network (p= 0.076), although this relationship was not significant. While results from these analyses were interpreted with caution as data collection is ongoing, results clearly do not show strong support for a positive relationship between learning performance and social complexity as predicted. Brown capuchins may gain a social benefit from cognitive abilities not tested or when the information learned has direct social implications. My findings suggest that there may not be a clear link between cognition and social behavior, or that our methods were not appropriate for answering this question.

Available for download on Sunday, May 09, 2021