Transmission mechanisms of fish electric signals

Fishes utilize electric signals for passive and active electrolocation and communication at night in murky water. To our knowledge, the mechanism of transmission of fish electric signals through water has not been addressed. In such a medium, the transmission of electrical signals can occur by movement of ions (ion conduction) under the influence of a generated electric field, or through its perturbation by nearby objects that have electric permittivity different than water. This latter property refers to the ability of a medium to resist the formation of electric fields with no involvement of ion transport. In this study, we discuss the relevance of each mechanism in the context of previous reports on transmission of signals by electric fishes in water environments.