Lifespan development of gaze following in wild chimpanzees

The ability to follow another’s gaze direction is a foundational skill in
human cognition that underpins more complex social abilities. Other
primate species also exhibit a variety of gaze-following behaviors, but
previous experimental work has focused only on captive populations.
Studies of cognition in wild animals are crucial to understanding the
biological context of different psychological processes, as well as to
characterize developmental change in cognition in animals interacting in
natural social groups. We therefore conducted field experiments with wild
chimpanzees (Pan troglodytes schweinfurthii) ranging from infancy to old
age in Kibale National Park, Uganda. Following our preregistered protocol
(https://aspredicted.org/N2D_DT4), chimpanzees observed a human
demonstrator who either looked up on test trials or down on control trials
across up to four trials presented on different days. Each trial was video
recorded in the field and coded by two experienced coders. In each trial,
we coded whether chimpanzees looked up during the trial, and if they did
we measured how quickly, calculated how much time they spent looking, and
whether they looked multiple times. The dataset includes
individual trial results for 53 individual wild chimpanzees including the
age and sex of each subject, as well as relevant controls.