Fish that are capable of generating electric discharges. A number of species, belonging to different families, have this capability. Some (e.g. Electrophorus electricus (electric eel) and the electric rays, such as the Atlantic Torpedo nobiliana) can produce strong, stunning currents capable of immobilizing potential prey. The electric organs are derived from muscle tissue which is organized as a series of units, each one acting as a type of battery. The electric eel (which is related to the carp, not to the true eel) also uses the electrical pulses as a navigational aid, as does the African elephant fish (Mormyridae).