Evolution and function of multimodal courtship displays

Abstract

Courtship displays are behaviours aimed to facilitate attraction and mating with the opposite sex and are very common across the animal kingdom. Most courtship displays are multimodal, meaning that they are composed of concomitant signals occurring in different sensory modalities. Although courtship often strongly influences reproductive success, the question of why and how males use multimodal courtship to increase their fitness has not yet received much attention. Very little is known about the role of different components of male courtship and their relative importance for females. Indeed, most of the work on courtship displays have focused on effects on female choice, often neglecting other possible roles. Additionally, a number of scientists have recently stressed the importance of considering the complexity of a display and the interactions between its different components in order to grasp all the information contained in those multimodal signals. Unfortunately, these methods have not yet been extensively adapted in courtship studies. The aim of this study was to review what is currently known about the functional significance of courtship displays, particularly about the role of multimodality in the courtship communication context. Emphasis is placed on those cases where a complete picture of the communication system can only be assessed by taking complexity and interaction between different modalities into account.

Keywords: elaborate displays; female preference; multisensory signals; sexual behaviour; sexual stimulation.

Figure 1

Multidimensional plots of female responses to multicomponent male courtship. Components A and B have different effects on female preference and female sexual stimulation, resulting in two three‐dimensional planes. (a) No interaction between components A and B. As component A increases, female sexual stimulation increases, but not female preference. Conversely, component B has a positive effect on female preference but does not influence female sexual stimulation. (b) An interaction exists between courtship components A and B. The effect of component A on female sexual stimulation increases as the magnitude of B increases. Component B alone does not have any effect on female sexual stimulation. [Based on Hebets et al. (2016) and Smith and Evans (2013)] [Colour figure can be viewed at wileyonlinelibrary.com]