Signal verification can promote reliable signalling.
The central question in communication theory is whether communication is reliable, and if so, which mechanisms select for reliability. The primary approach in the past has been to attribute reliability to strategic costs associated with signalling as predicted by the handicap principle. Yet, reliability can arise through other mechanisms, such as signal verification; but the theoretical understanding of such mechanisms has received relatively little attention. Here, we model whether verification can lead to reliability in repeated interactions that typically characterize mutualisms. Specifically, we model whether fruit consumers that discriminate among poor- and good-quality fruits within a population can select for reliable fruit signals. In our model, plants either signal or they do not; costs associated with signalling are fixed and independent of plant quality. We find parameter combinations where discriminating fruit consumers can select for signal reliability by abandoning unprofitable plants more quickly. This self-serving behaviour imposes costs upon plants as a by-product, rendering it unprofitable for unrewarding plants to signal. Thus, strategic costs to signalling are not a prerequisite for reliable communication. We expect verification to more generally explain signal reliability in repeated consumer-resource interactions that typify mutualisms but also in antagonistic interactions such as mimicry and aposematism.
Department of Mathematics, City University London, , London EC1V 0HB, UK, School of Biology, University of St Andrews, , St Andrews KY16 9TH, UK, Faculty of Biology, Department of Evolutionary Biology and Animal Ecology, University of Freiburg, , Hauptstrasse 1, 79104 Freiburg, Germany.
Mark
M
Broom
Graeme D
GD
Ruxton
H Martin
HM
Schaefer
D000818:Animals; D005075:Biological Evolution; D002755:Choice Behavior / Q000502:physiology*; D003142:Communication; D020387:Food Chain; D005638:Fruit / Q000502:physiology; D008954:Models, Biological; D018521:Plant Physiological Phenomena / Q000502:physiology*; D013559:Symbiosis
aposematism; handicap principle; honest signalling; mimicry; plant–animal communication; sanction