The theme we present here is that there may be a set of very general and constant pressures that have shaped the functions of auditory systems throughout vertebrate evolution. The general factor may be a capacity for a sort of auditory scene analysis that we assume to have been important throughout the evolution of vertebrate hearing. In this review we concentrate
on hearing mechanisms of ¢shes because these vertebrates illustrate functions and functional relationships in the auditory system that tend to be widely shared among vertebrates. There are also instances where the same basic structures are found throughout the vertebrates
and provide the basis for many of the shared functions of the auditory system.