From Cues to Signals: Evolution of Interspecific Communication Via Aposematism and Mimicry in a Predator-Prey System

Current evolutionary theory suggests that many natural signaling systems evolved from preexisting cues. In aposematic systems, prey warning signals benefit both predator and prey. When the signal is highly beneficial, a third species often evolves to mimic the unpalatable species, exploiting the signaling system for its own protection. We investigated the evolutionary development of predator cue utilization and prey signaling in a digital predator-prey system in which mimicking prey could evolve to alter their appearance to resemble poison-free or poisonous prey. In predators, we observed rapid evolution of cue recognition (i.e. active behavioral responses) when presented with sufficiently poisonous prey. In addition, active signaling (i.e. mimicry) evolved in prey under all conditions that led to cue utilization. Thus we show that despite imperfect and dishonest signaling, given a high cost of consuming poisonous prey, complex systems of interspecific communication can evolve via predator cue recognition and prey signal manipulation. This provides evidence supporting hypotheses that cues may serve as stepping-stones in the evolution of more advanced communication systems and signals incorporating information about the environment.