New research shows that a number of fishes use electric fields to attract females of their species.  It is also used to intimidate rivals.  An Amazon fish has been taken as a case study.  This research is undergone in Florida International University at Miami.  Behavioral ecologist Vielka Salazar is undergoing research and published it is Live Science.  The gymnotiform fish has been studied.  The male of this species of fishes gives off long electric hums almost like serenades at night.