DOI: 10.5061/dryad.3g87c35
title: Data from: Flexible gaze-following in rhesus monkeys

description: Humans are characterized by complex social cognitive abilities that emerge
 early in development. Comparative studies of nonhuman primates can
 illuminate the evolutionary history of these social capacities. We
 examined the cognitive skills that rhesus monkeys (Macaca mulatta) use to
 follow gaze, a foundational skill in human social development. While
 rhesus monkeys can make inferences about others’ gaze when competing, it
 is unclear how they think about gaze information in other contexts. In
 study 1, monkeys (n = 64) observed a demonstrator look upwards either in a
 barrier condition where a box was overhead, so that monkeys could not see
 the target of her gaze, or a no barrier condition where nothing blocked
 her view. In study 2, monkeys (n = 59) could approach to observe the
 target of the demonstrator’s gaze when the demonstrator looked behind a
 barrier on the ground or, in the no barrier condition, behind a window
 frame in the same location. Monkeys were more likely to directly look up
 in study 1 if they could initially see the location where the demonstrator
 was looking, but they did not preferentially reorient their bodies to
 observe the out-of-view location when they could not see that location. In
 study 2, monkeys did preferentially reorient, but at low rates. This
 indicates that rhesus monkeys can use social cognitive processes outside
 of competitive contexts to model what others can or cannot see, but may
 not be especially motivated to see what others look at in non-competitive
 contexts, as they reorient infrequently or in an inconsistent fashion.
 These similarities and differences between gaze-following in monkeys and
 children can help to illuminate the evolution of human social cognition.
description: Flexible Gaze Study 1
 (Bettle & Rosati)Trial data from Study 1
 (overhead barrier). Key for variable codes included as a separate tab in
 the file.Bettle-Rosati-FlexibleGaze-Study1-DRYAD.xlsFlexible Gaze Study 2 (Bettle & Rosati)Trial data from Study 2 (reorienting around a barrier). Key for variable codes included as a separate tab in the file.Bettle-Rosati-FlexibleGaze-Study2-DRYAD.xlsMovie S1 - Overhead barrierSupplemental Movie S1: Overhead barrier (Study 1). In the demonstration for the barrier condition, the actor first looks up for 10s (looking phase), and then walks away so the subject can approach the apparatus for up to one minute (approach phase). The procedure for the no barrier condition is identical, but there is no barrier blocking the actor’s line of sight. Following these demonstrations are an example of a monkey following the actor’s gaze in the looking phase, and an example of a monkey reorienting by approaching the barrier during the approach phase.Movie S2 - Reorienting around a barrierSupplemental Movie S2: Reorienting around a barrier (Study 2). In the demonstration for the barrier condition, the actor first looks directly behind the barrier for 5s, and then walks away so the subject can approach the apparatus for up to 30s (approach phase). The procedure for the no barrier condition is identical, but the apparatus has a transparent window so that the subject can see the demonstrator’s visual target from their initial position. Following these demonstrations are an he example of a monkey approaching the barrier and looking behind it.