The face is central to primate multicomponent signals

Abstract A wealth of experimental and observational evidence suggests that faces have become increasingly important in the communication system primates over evolutionary time both static moveable aspects convey considerable information. Therefore, whenever there is a visual component to any multicomponent signal face potentially relevant. However, role not always considered primate research. We review literature make case for greater focus on going forward. propose can be overlooked two main reasons: first, due methodological difficulty. Examination signals difficult, so scientists tend examine limited number combination. Detailed examination subtle dynamic components facial particularly hard achieve studies primates. Second, common assumption contains “emotional” content. priori categorisation behavior as ignores communicative predictive information present might contribute signals. In short, we argue central (and also many multimodal signals) suggest future directions investigating this phenomenon.