Symposium on Agroacoustics: Acoustic Signals, Arms Races and the Costs of Honest Signalling
Animal signals evolve as adaptations to social as well as physical environments. Where the interests of signallers and responders differ, a coevolutionary "arms race" cycle of signal adoption, exaggeration, and devaluation may result. Stable, reliable signals evolve when costs of signalling constrain the evolution of bluff and exaggeration. Acoustic signals are especially costly, compared to other signal types, and are therefore especially likely to evolve as reliable signals in such "social competition" situations. Costs of acoustic signals include physiological costs of growth and signal production, probes by conspecific rivals and discriminating members of the other sex, and attacks by natural enemies such as predators and parasites.