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The elephantnose fish is a weakly electric fish which generates an electric field with its electric organ, detects small variations in the field with its electroreceptors, and processes the detected signals in the brain to locate nearby objects. [12] Weakly electric fish generate a discharge that is typically less than one volt.
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 .
Electric eel skeleton, with the long vertebral column at top, the row of bony rays below. Electric eels have long, stout bodies, being somewhat cylindrical at the front but more flattened towards the tail end. E. electricus can reach 2 m (6 ft 7 in) in length, and 20 kg (44 lb) in weight. The mouth is at the front of the snout, and opens upwards.
Active electrolocation is practised by two groups of weakly electric fish, the Gymnotiformes (knifefishes) and the Mormyridae (elephantfishes), and by Gymnarchus niloticus, the African knifefish. An electric fish generates an electric field using an electric organ, modified from muscles in its tail. The field is called weak if it is only enough ...
The convergent evolution between the South American gymnotiforms and the African Mormyridae is remarkable, with the electric organ being produced by the substitution of the same amino acid in the same voltage-gated sodium channel despite the two groups of fish being on different continents and the evolution of the electric sense organ being ...
Electric catfish (centre) in Mastaba of Ti bas-relief, Saqqara, ancient Egypt [1] The electric catfish of the Nile was well known to the ancient Egyptians. [2] The Egyptians reputedly used the electric shock from them when treating arthritic pain. [3] They would use only smaller fish, as a large fish may generate an electric shock from 300 to ...
Gymnotiformes and Mormyridae have developed their electric organs and electrosensory systems (ESSs) through convergent evolution. [30] As Arnegard et al. (2005) and Albert and Crampton (2005) show, [ 31 ] [ 32 ] their last common ancestor was roughly 140 to 208 Mya, and at this time they did not possess ESSs.
Electric catfish or Malapteruridae is a family of catfishes (order Siluriformes). This family includes two genera, Malapterurus and Paradoxoglanis, with 21 species. [1] Several species of this family have the ability to generate electricity, delivering a shock of up to 350 volts from its electric organ. [2]