Speaker
Description
The ability to follow the gaze of conspecifics can provide valuable information about the environment and may be essential for developing more advanced socio-cognitive skills in both humans and other species. In this study, we took a comparative approach to investigate whether robust capuchin monkeys (Sapajus spp.) can follow the gaze of their conspecifics. We presented 10 subjects with photographs of conspecifics’ faces on a touchscreen and measured the time it took to touch a dot that appeared beside each picture after a very short delay (300 or 600 ms). The photographs depicted familiar or unfamiliar conspecifics, and the dot appeared aligned with the direction of their gaze (congruent trials) or in the opposite direction (incongruent trials). We predicted that if capuchin monkeys follow the gaze of the conspecific shown in the picture, their response time would be shorter for congruent trials than for incongruent trials. We also expected that this effect would be stronger for familiar conspecifics than for unfamiliar conspecifics. Contrary to our predictions, we found that the response time was significantly longer for congruent trials than for incongruent trials. Furthermore, this effect was not affected by the familiarity of the conspecifics. These results suggest that gaze following may be less prevalent than previously thought or could be sensitive to specific experimental conditions, such as still 2D images rather than real-life subjects. It is also possible that capuchin monkeys tend to avoid looking directly at the gaze of conspecifics.
