Inferential learning explains association between self-relevance cues and overlap in chimpanzee visual bodily gesture repertoires

Roberts, AI, Sorokowski, P and Roberts, SGB ORCID: 0000-0003-3986-0254 (2026) Inferential learning explains association between self-relevance cues and overlap in chimpanzee visual bodily gesture repertoires. Behavioral Ecology and Sociobiology, 80 (10). ISSN 0340-5443

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Abstract

We investigated whether the association of self-relevance cues with overlap in visual bodily gestures is better explained by inferential learning or experience-based reinforcement of gesture–outcome contingencies. Inferential accounts predict that self-relevance cues facilitate convergence by supporting goal inference in complex socio-ecological situations, in secondary contexts and responses. In contrast, experience-based accounts predict that self-relevance cues facilitate repeated exposure, promoting convergence through reinforcement of stable gesture–outcome associations in primary contexts. Using generalized linear mixed models and social network analyses of 12 wild East African chimpanzees, we examined relationships among self-relevance cues, social relationships, socio-ecological conditions, contextual specificity, and gestural repertoire overlap. Overall, the results are more consistent with inferential accounts than reinforcement accounts. Although reciprocated social bonds provided opportunities for reinforcement learning, they did not predict repertoire overlap, indicating exposure is insufficient for convergence. Three findings supported inferential account. First, self-relevance cues accompanied heterogeneous gestures in socially complex and uncertain situations, including interactions with non-kin, larger parties, and weaker bonds. Second, self-relevance cues such as vocalizations, manual gestures, and response waiting were associated with secondary contexts and responses rather than with primary contexts expected under reinforcement learning. Third, repertoire convergence was predicted by gestures in secondary contexts, whereas gestures in primary contexts did not predict convergence. Consistent with inferential account, these findings suggest that self-relevance cues may facilitate inference of communicative goals under uncertainty, potentially supporting flexible alignment of gestural repertoires in dynamic fission–fusion societies, explaining how gestural convergence and divergence coexist, making gesture culture likely.

Item Type:	Article
Uncontrolled Keywords:	05 Environmental Sciences; 06 Biological Sciences; 07 Agricultural and Veterinary Sciences; Behavioral Science & Comparative Psychology; 30 Agricultural, veterinary and food sciences; 31 Biological sciences; 41 Environmental sciences
Subjects:	B Philosophy. Psychology. Religion > BF Psychology Q Science > QL Zoology
Divisions:	Psychology (from Sep 2019)
Publisher:	Springer
Date of acceptance:	28 August 2026
Date of first compliant Open Access:	7 September 2026
Date Deposited:	07 Sep 2026 13:38
Last Modified:	07 Sep 2026 13:38
DOI or ID number:	10.1007/s00265-026-03796-4
URI:	https://researchonline.ljmu.ac.uk/id/eprint/29333

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