How noise determines the evolution of communication

This essay focuses on a dozen predictions from a previous analysis of the evolution of communication in the presence of noise. First of all, (1) noise creates an unavoidable trade-off between two kinds of error by receivers. Furthermore, (2) a receiver's optimal criterion for response depends on the level of signals and (3) a signaller's optimal level of signalling depends on the receiver's criterion. As a result, (4) communication in noise can evolve to a joint optimum. (5) Communication at a joint optimum is honest on average. (6) Joint optima for communication in noise do not eliminate noise. (7) Many parameters of communication in noise remain poorly studied. (8) Noise leads to strong predictions for the evolution of exaggeration and thresholds. (9) Signals for advertising and for warning are contrasts in probable costs of errors. (10) The evolution of new signals and responses encounters a hurdle. (11) New signals and responses can evolve by exploitation. (12) Joint evolution of signallers and receivers has a predictable direction. These predictions will remain untested hypotheses until communication in noise is studied more thoroughly than it has been previously.