Noisy communication and the evolution of cooperation

We analyze an evolutionary model with noisy pre-play communication, where the message received can differ from the message sent without the sender being aware of this. Noise implies that an inefficient strategy cannot push unsent messages, allowing these messages to be used by a mutant in order to coordinate upon an efficient outcome. This ensures that any neutrally stable strategy is efficient. Since noise restricts drift, we also have existence of evolutionarily stable sets in a larger class of games than hitherto known. (C) 1998 Academic Press.