Lifespan development of gaze following in wild chimpanzees

Sabbi, Kris 1 2 ; Monroe, Isabelle3; Rosati, Alexandra 3 ; Machanda, Zarin2

Published Jan 19, 2026 on Dryad. https://doi.org/10.5061/dryad.tmpg4f5d5

Data files

Jan 19, 2026 version files 25.19 KB

README.md

4.69 KB
Sabbi_etal_chimpanzee_gazeFollowing.xlsx

20.50 KB

Abstract

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.

Dataset DOI: 10.5061/dryad.tmpg4f5d5

Description of the data and file structure

This data set consists of one file (.xlsx format) with the data from this study. The file includes a data tab with all the data from the task, as well as a key tab where all the variables reported in the main data tab are defined (also appended below).

Wild chimpanzees were tested on gaze-following task where they were tested up to four trials at different times. The file includes the demographic characteristics of the chimpanzees that participated in the task (e.g., their age and sex); the relevant experimental parameters for the task (e.g., trial number and condition), and their responses (e.g., gaze following responses and the dynamics of these responses). NA values are defined for each variable and indicate that a particular response measure was not applicable to that chimpanzee (e.g., if they did not produce a gaze following response, their latency to look is blank).

Detailed methodological procedures are described in the associated paper.

Files and variables

File: Sabbi_etal_chimpanzee_gazeFollowing.xlsx

Description: Data from a field experiment examining patterns of gaze following in wild chimpanzees (Pan troglodytes schweinfurthii).

Variables

Variable	Description
Subject	Anonymized individual identifier assigned to each unique chimpanzee in the study
Sex	Sex of the subject (Female or Male)
Age	Numerical age of the subject in years, calculated on the specific day of that trial (e.g., chimpanzees may have different calculated ages on different trials)
Cohort	Categorical age: infants under 5 years old, juveniles 5-10 years old, adults 10-25 years, and older adults over 35 years
Experimenter	Identifier assigned to each unique demonstrator (i.e. the experimenter for that trial; 1 or 2)
Condition_Order	Whether the first test for that subject was a Control or a Test trial
Trial_number	Trial number for total sequence of trials in order (1-4)
Trial_number_type	Whether the trial was the first or second trial for that trial type (e.g., 1st or 2nd test trial, 1st or 2nd control trial)
Condition	Whether the experimenter produced a look up (Test) or a neutral look down (Control)
LookYN	Did the chimpanzee look up during the trial? (yes = 1, no = 0)
Latency	The latency in seconds to produce a looking response (for trials in which the chimpanzee produced a look upwards; blanks indicate the chimpanzee did not look)
Total_Looking	The total duration of looking in seconds (for trials in which the chimpanzee produced a look upwards; blanks indicate the chimpanzee did not look)
Multiple_LooksYN	Whether the chimpanzee produced multiple discrete looks (for trials in which the chimpanzee produced a look upwards; 1 = yes, 0 = no, only one look; blanks indicate the chimpanzee did not look)