Multicomponent and Multimodal Lipsmacking in Crested Macaques (Macaca nigra)

Abstract

Primates' communicative signals are often dynamic and composed of multiple components, sometimes belonging to different sensory modalities. Such multicomponent signals are of crucial importance in the study of communication: the addition of extra features to a signal has the potential to modulate or change the meaning and message of the specific signal. Traditionally, however, components of compound signals are studied in isolation from each other, or communicative displays are studied as static and invariant wholes. Both approaches may not allow us to assess the full function of the signals. In crested macaques (Macaca nigra), the lipsmack (a display mainly used in affiliative interactions) can be produced alone or combined with other visual and acoustic communicative features. We investigated whether the composition of the lipsmack influenced the outcome of social interaction while controlling for relationship quality. Our results show that lipsmacks composed of both visual and vocal components (i.e. multimodal signals) increased the probability of affiliative contact, and therefore have enhanced signal value. The total number of visual components involved in the display had no effect but some visual components seemed more influential than others. By analyzing lipsmacking behavior as a composite, dynamic display, we were able to reveal a level of complexity that is not apparent when looking at each component separately. The results highlight the importance of a more integrative, multimodal approach to the study of primate communication.

Wild chimpanzees’ use of single and combined vocal and gestural signals

“…In great apes, this was largely done with captive groups (Leavens and Hopkins 2005; Pollick and de Waal 2007; Pollick et al 2008; Leavens et al 2010; Genty et al 2014). One common conclusion from this research has been that ‘multimodal’ signals in primates evolved not to enlarge the range of information that could be communicated, but simply to enhance detection (Pollick and de Waal 2007; Leavens et al 2010; Micheletta et al 2012; although c.f. Genty et al 2014 for some evidence of additional communicative cues provided by bonobo vocal-gestural combinations), a hypothesis further supported by neurobiological data (Taglialatela et al 2011).…”

“…Following a seminal paper by Partan and Marler (1999), a number of researchers took up the challenge of investigating ‘multimodality’ in non-human primate communication (Partan 2002; Palagi and Norscia 2008; Micheletta et al 2012; Higham et al 2013; Rigaill et al 2013; Wilke et al 2017). In great apes, this was largely done with captive groups (Leavens and Hopkins 2005; Pollick and de Waal 2007; Pollick et al 2008; Leavens et al 2010; Genty et al 2014).…”

“…Within the primate literature, some researchers have adopted this definition (e.g. Partan 2002; Palagi and Norscia 2008; Micheletta et al 2012; Rigaill et al 2013). However, other researchers have used the term multimodal signalling to refer to the combination of different signal types , such as a gesture, vocalization, or facial expression (Pollick and de Waal 2007; Liebal et al 2013; Genty et al 2014; Wilke et al 2017).…”

Facial expression: An under-utilised tool for the assessment of welfare in mammals

“…Communication is multi-modal and may contain auditory, visual or olfactory components, dependent on context and distance between signaler and receiver (Parr et al, 2005;Burrows, 2008, da Cunha andByrne, 2009;. Signaling is important for social information transfer, and facilitates affiliation, spacing, agonistic intent, or predator avoidance (Partan, 2002;da Cunha and Byrne, 2009;Kiriazis and Slobodchikoff, 2006;Micheletta et al, 2013). Facial expressions are most important for communicating in close range interactions and may indicate signaler configuration performed in negative situations (e.g., anger), which arises from contraction of the eyelids and sometimes by lowering of the eyebrow (Waller et al, 2008a).…”

“…Facial and vocal communications are motivationally linked, and are combined for multi-modal social expression (Andrew, 1963;Chevalier-Skolnikoff, 1973;Lehner, 1978;Partan, 2002;Micheletta et al, 2013). Both may be important measures of welfare and facial expressions created in the production of sound should be differentiated rather than disregarded.…”