Communication in discrete action-response games

I present a simple game, the Basic Action-Response game, which allows investigation of the claim that signals must be costly to be reliable. The Basic Action-Response game is the simplest communication game possible, by investigating its parameters we are able to define clearly “conflict”, “handicap”, “communication” and other relevant concepts. I explore the conditions on the magnitude of the stabilizing cost and handicap that must hold in order to maintain the evolutionary stability of signalling. It will be demonstrated that stable communication need not make use of costly signals at ESS, not even “on average”, and that “negative handicaps” can be stable as long as the stabilizing cost is large enough.