The Amazing Electric Fishes
The electric organs are specialized organs, derived from the muscles or the nerve cell's axon, that can generate electric current, employed from catching the prey (electro-paralysis) to defense, orientation (electro-location, similar the way bats and dolphins use ultrasounds in ecolocation), or as a means of communication, for mating, feeding or territory defense. The electric fish, producing electricity, are electrogenic, but as they sense the electricity they are also electroreceptive.
There are species that are not electrogenic, being only electroreceptive, detecting the weak fields generated by their prey (any living thing generates a weak electric field, which could be just 0.01 microvolts), like sharks, rays (except the electric ones, which are also electrogenic), lungfishes and even ... the platypus (a mammal!). It clearly appears that electricity works only in water.
There are species that are not electrogenic, being only electroreceptive, detecting the weak fields generated by their prey (any living thing generates a weak electric field, which could be just 0.01 microvolts), like sharks, rays (except the electric ones, which are also electrogenic), lungfishes and even ... the platypus (a mammal!). It clearly appears that electricity works only in water.
