This chapter provides a broad overview of terminology and concepts in the study of animal communication. First, we focus on the evolutionary origins or phylogenetic causes of communicative signals. We address how communication systems can arise under several circumstances by increasing the reproductive success of both senders and receivers of signals. We summarize terminology describing what is communicated (self-reporting and other-reporting), how it is communicated (different modalities) and to whom it is communicated (conspecifics, heterospecifics). We further discuss how signal design is influenced by the risk of deception. The debate between the information and manipulation perspective of animal communication is briefly outlined. The second part of the chapter focuses on proximate aspects of animal communication. We describe signal acquisition in animals through ultimate mechanisms (biological inheritance, phylogenetic ritualization) and proximate mechanisms (ontogenetic ritualization, cultural learning) with a particular focus on learning. We further discuss signal selection, i.e., to what degree some animals have flexible control over signals and how they adjust them according to the recipient. Last, we discuss new directions and open questions in the study of animal communication, i.e., considerations of compositionality and multimodality, turn-taking, repertoire acquisition and development, flexibility and memory, and the problem of using a one-size-fits-all approach for understanding animal communication systems.

Chapter 16 focuses on the ability for certain members of the animal kingdom to communicate. It first compares the notions of communication and language and examines the ways in which animals may signal information through visual, auditory, chemosensory, mechanoreceptive, and electromagnetic channels. It explains the type of information conveyed by animal communication including alarm, food, mating, and aggressive signals. The chapter then lists the properties that researchers have considered basic to all human languages, including not only arbitrariness of symbols, discreteness, displacement, semantics, productivity, and duality, but also grammar and recursion. The chapter then shows that many of these well-known properties are also found at least in some members of the animal kingdom, namely in the signals of prairie dogs and honeybees.

In this chapter, we apply the affective social learning (ASL) concept to the social learning of natural skill sets in immature orang-utans since it can serve as an illustration of the majority of learning that occurs in wild apes. Most orang-utan social learning happens during everyday tasks and without any active involvement of the role model. Consequently, detecting the emotional state(s) of the role model is nearly impossible. We focus therefore on the emotional responses of the immature learners to the role models’ behaviours. Our data on peering (attentive, sustained close-range watching of conspecifics), which is often followed by selective practice of the observed behaviour by the peerer, suggests that there is some highly specific emotional arousal of the immatures during social learning. The role models’ actions with the object seem to play a central role in the learning process. However, immatures appear to decide on their own whether to attend to the information or not, as in affective observation, the second stage of ASL. Developmental changes in role-model preferences support the notion that trust in the role model is critical for ASL to work. Given that we can use the learners’ responses as proof of the affective states of the role models, ASL may be an important part of the mechanism that guides and optimizes the acquisition of learned skills in wild great apes. However, the lower we set the bar for the affective states (or emotions) of the role models for ASL to work, the more difficult it is to verify their presence and the more ASL will overlap with ordinary social learning.

Emotions have often been considered negatively in the animal literature, offering so-called parsimonious explanations to uncontrolled animal behaviour. This has particularly been the case for primate vocalizations, as opposed to flexible human language and potential goal-directed primate gestures. We believe that affective social learning (ASL) can offer a useful way to analyse emotions through a different perspective, integrating emotions and learning to analyse primates’ and other animals’ behaviour. In this chapter, we review the primate literature for potential cases of ASL, re-analysing classic cases such as the vervet alarm call system as well as more recent discoveries related to emotional behaviour. To decipher whether ASL is cognitively possible for non-human primates, we dissect the cognitive requirements for each step of ASL: emotional contagion, affective observation, social referencing and natural pedagogy. Our review suggests that, despite the lack of evidence for the latter step, there is evidence for all other types of ASL in primates, particularly in the domains of the ontogeny of communicative and cultural learning. We conclude by highlighting that ASL may constitute a useful comparative framework to describe various types of teaching that do not necessitate the demanding requirement of full-blown human intentional teaching.