Grund Charlotte, Robbins Martha M, Hobaiter Catherine
School of Psychology and Neuroscience, University of St Andrews, St Andrews, UK.
Department of Primate Behavior and Evolution, Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany.
Anim Cogn. 2025 Jul 29;28(1):73. doi: 10.1007/s10071-025-01977-8.
Over recent decades comprehensive catalogues of vocal, facial, and gestural signals have been established for most great ape species; however, a systematic description of wild gorilla gestural behaviour, particularly of the Eastern gorilla species, remains missing. We address this absence by cataloguing the physical form of gestural units used by 49 habituated wild mountain gorillas (Gorilla beringei beringei) from four social units in the Bwindi Impenetrable National Park, Uganda (n = 157 observation days over 8 months). We obtained a dataset of n = 3220 instances of intentional gesture, coded with a systematic ELAN-based framework (GesturalOrigins). Mountain gorillas employed a repertoire of 63 gesture actions, including potentially species-specific units, across 10 behavioural contexts. A latent class analysis on variants of gesture action expression split units further into 126 finer-grained forms ('morphs'). We observed ~ 6 gestures per hour of observation time and species-level repertoire size was similar to those reported in both Pan species. Our study constitutes the first systematic description of the mountain gorilla gestural repertoire, providing a new understanding of their communication, filling current gaps in great ape gestural phylogeny, and complementing previous studies on their vocal signals. Living in cohesive, small-sized female-male bonded social units, gorillas show striking differences in social organisation as compared to Pan species and provide crucial context for theories on the potential ancestral states of human communicative behaviour.
在最近几十年里，已经为大多数大猩猩物种建立了声音、面部和手势信号的综合目录；然而，对野生大猩猩手势行为，特别是东部大猩猩物种的手势行为，仍缺乏系统的描述。我们通过对乌干达布温迪难以穿越国家公园四个社会单元中的49只习惯化野生山地大猩猩（Gorilla beringei beringei）使用的手势单元的物理形式进行编目，来填补这一空白（8个月内共157个观察日）。我们获得了一个包含3220个有意手势实例的数据集，并使用基于ELAN的系统框架（GesturalOrigins）进行编码。山地大猩猩在10种行为情境中使用了63种手势动作，包括可能特定于该物种的单元。对手势动作表达变体的潜在类别分析将单元进一步细分为126种更精细的形式（“形态”）。我们在每小时的观察时间内观察到约6种手势，物种层面的全部手势数量与两种黑猩猩物种报告的数量相似。我们的研究首次对山地大猩猩的全部手势进行了系统描述，为它们的交流提供了新的理解，填补了当前大猩猩手势系统发育研究的空白，并补充了之前关于它们声音信号的研究。大猩猩生活在凝聚力强、规模小的雌雄结合的社会单元中，与黑猩猩物种相比，它们在社会组织方面表现出显著差异，为关于人类交流行为潜在祖先状态的理论提供了关键背景。
