Behaviour 2019
Social eye tracking in a pair-bonded, neotropical primate
Allison R. Lau1, Louise Loyant2, Karen L. Bales1, Sara M. Freeman3. 1University of California, Davis, Davis, CA, United States; 2University of Portsmouth, Portsmouth, , United Kingdom; 3Utah State University, Logan, UT, United States

Social bonds are crucial to many animal species. To maintain these bonds, individuals must be able to recognize social others. Primates rely heavily on visual signals, but some neotropical monkeys rely on other communication modalities to gather social information. Little is known about how highly social, neotropical primates devote their visual attention to conspecifics. To characterize visual attention, we used coppery titi monkeys (Plecturocebus cupreus) that form pair-bond attachments in which to assess visual attention in an eye tracking paradigm. Using a previously validated non-invasive eye tracking method, we presented adult titi monkeys with ten slides of social stimuli that each showed two faces side-by-side: either their partner’s face and a stranger’s face or two strangers’ faces. Face side was counterbalanced across all subjects and slide presentation order was randomized across the subject pool. Here, we present the time to first fixation, fixation duration, fixation count, visit duration, and visit count for partner vs. stranger faces. This study is the first to characterize social looking in a pair-bonded monkey.