Electroreception

Electroreception is the sensory ability of some species of animals to detect weak, naturally occurring [Page 385]electrostatic fields in their environment. It is found in the most ancient lineages of fishes and survives today in about 10% of all vertebrate species—all of which are aquatic. Electroreception was lost in evolution when vertebrates crawled onto land, so we humans can only imagine the perception of an electrical world with this sixth sense. For reasons unknown to biologists, electroreception was also lost among the ancestors of the modern fishes only to reappear in two separate lineages of ray-finned, or teleost fishes. The sense also appeared independently with the evolution of the monotreme mammals such as the platypus and echidna. All electroreceptive species possess sensitive electroreceptor organs in ...