Electric organ (fish)
In biology, the electric organ is an organ that an electric fish uses to create an electric field. Electric organs are derived from modified muscle or in some cases nerve tissue, called electrocytes, and have evolved at least six times among the elasmobranchs and teleosts. These fish use their electric discharges for navigation, communication, mating, defence, and in strongly electric fish also for the incapacitation of prey.
The electric organs of two strongly electric fish, the torpedo ray and the electric eel were first studied in the 1770s by John Walsh, Hugh Williamson, and John Hunter. Charles Darwin used them as an instance of convergent evolution in his 1859 On the Origin of Species. Modern study began with Hans Lissmann's 1951 study of electroreception and electrogenesis in Gymnarchus niloticus.
Anatomy[edit]
Organ location[edit]
In most electric fish, the electric organs are oriented to fire along the length of the body, usually lying along the length of the tail and within the fish's musculature, as in the elephantnose fish and other Mormyridae.[14] However, in two marine groups, the stargazers and the torpedo rays, the electric organs are oriented along the dorso-ventral (up-down) axis. In the torpedo ray, the organ is near the pectoral muscles and gills.[15] The stargazer's electric organs lie behind the eyes.[16] In the electric catfish, the organs are located just below the skin and encase most of the body like a sheath.[1]