Social tolerance in group-living animals can be viewed as a counterweight against competitive interests necessary to obtain coexistence equilibrium and maintain group cohesion. As such, it forms an interesting phenomenon to study at the group-level, but how can this be done most informatively? Here, we use three group-level co-feeding assays and social network analysis to study social tolerance in two groups of chimpanzees living under similar circumstances within a sanctuary to i) reassess whether social tolerance may be a group-specific parameter in chimpanzees and derive inferences about its long-term stability, and ii) compare the characteristics and resultant patterns between two established and one new assay. We show that the three assays expose the same (predicted) group-level differences in social tolerance as in the previous study eight years ago, thereby providing preliminary evidence for stability in group-specific levels of social tolerance in chimpanzees, despite changing group compositions. Furthermore, from an experimental point of view, we identify the new assay as more valid than the two established ones based on the consideration that resources may deplete at different rates across groups, which would consequently alter the need for tolerance differentially. We discuss implications for the study of social tolerance and highlight the importance of taking into account intraspecific variation in social animals.

Experimental data collected by Van Donink. Data scored from video.

The data in the file "van Leeuwen_experimental co-feeding data" are organized such that each line represents one scan of the co-feeding experiment. Each line states the date, the scan, the group in which the experiment (assay) took place, the number of co-feeding group members and the total number of group members in the enclosure during that scan. These data are the input data for the GLMMs as explained in the manuscript.

The data in the file "van Leeuwen_experimental proximity data" are organized such that on each sheet per scan the subjects are noted in a single dyadic-format column that were in close proximity to each other while co-feeding during the experiment. Each sheet corresponds to one assay (separate for each group). These data are the input data for the social network analysis as explained in the manuscript.