Bonobo and chimpanzee gestures overlap extensively in meaning
Gesture types that were analysed for ASO distribution (video examples for all gesture types can be found at http://greatapedictionary.wp.st-andrews.ac.uk/video-resources/gesture-videos/).
All ASOs are given for each gesture type, in descending order from most to least frequent, as a percentage of all instances for all ASOs included in analysis (values in S1 Table, raw data in S1 Data). For bonobos, results for ANOVA are given in square brackets, e.g., [N(n): ANOVA results], with N as number of individuals and n as number of gesture instances (for age and sex of contributing individuals, see S2 Table); a significant effect shows that gesture usage differs from the average distribution of gesture frequencies. For chimpanzees, ANOVA or chi-squared analyses were performed ; square brackets contain published results. Underlined ASOs are shared by both chimpanzees and bonobos for that gesture type. This chi-squared analysis was conducted in Hobaiter & Byrne 2014 after checking and finding no effect of signaller identity on gestural meaning. We have included it for comparison but recognise that chi-squared analyses risk pseudoreplication. For analyses, we combined several ASOs from : ‘Initiate copulation’ includes ‘Sexual attention—female’ and ‘Sexual attention—male’; ‘Initiate grooming’ includes ‘initiate grooming’ and ‘direct attention’; ‘Travel with me’ includes ‘Travel with me (adult)’ and ‘Travel with me (young)’. ASO, Apparently Satisfactory Outcome.