The loud scratch: a newly identified gesture of Sumatran orangutan mothers in the wild.

ABSTRACT: The communicative function of primates' self-directed behaviours like scratching has gained increasing attention in recent years, but their intentional use is still debated. Here, we addressed this issue by exploring the communicative function of 'loud scratches' in wild Sumatran orangutans. Building on previous studies in chimpanzees, we examined the prediction that audio-visual loud scratches are used communicatively in mother-infant travel coordination. Specifically, we examined whether individual, social and scratch features affected the use of pre-move scratches, markers of intentional signal use and approach responses. We analysed a total of 1457 scratching bouts, produced by 17 individuals (including four mothers and their dependent offspring) observed during 305 h of focal follows.

SUBMITTER: Frohlich M 

PROVIDER: S-EPMC6684992 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature