|Meaning, Cost and Convention: How Signaling Costs Can Shape the Meaning of Signals|
|Kia W. Seehafer, David W. Stephens. University of Minnesota, Twin Cities, MN, United States
Conventions determine the meanings of words in human language. Do conventional meanings exist in nonhuman communication? If so, game theoretical tools would provide a powerful tool to analyze meaning. Yet, early behavioral ecologists (e.g., Zahavi & Maynard Smith) rejected nonhuman conventional communication, arguing that the conflicts of interest that nearly always exist between nonhuman signalers and receivers prevent conventions. It is difficult to fully understand this argument because these early behavioral ecologists had a fairly primitive understanding of conventions. We re-consider the Zahavi-Maynard Smith argument using a modern definition of signaling conventions. In a situation with two possible signal systems without conflicts of interest, both constitute stable equilibria of the signaling game, so the meaning of the signal is, by definition, conventional. We show that introducing conflicts of interest destabilizes both signaling systems, so we lose not only signaling conventions, but all signaling. Additionally, we show that any sufficiently large cost differential can stabilize one signaling system; direction of the cost difference determines which persists.