The evolutionary origins of electric signal complexity

@article{Stoddard2002TheEO,
  title={The evolutionary origins of electric signal complexity},
  author={Philip K. Stoddard},
  journal={Journal of Physiology-Paris},
  year={2002},
  volume={96},
  pages={485-491}
}
  • P. Stoddard
  • Published 1 September 2002
  • Biology, Medicine
  • Journal of Physiology-Paris
This study explores the evolutionary origins of waveform complexity in electric organ discharges (EODs) of weakly electric fish. I attempt to answer the basic question of what selective forces led to the transition from the simplest signal to the second simplest signal in the gymnotiform electric fishes. The simplest electric signal is a monophasic pulse and the second simplest is a biphasic pulse. I consider five adaptive hypotheses for the evolutionary transition from a monophasic to a… 
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It is concluded that selective forces from the abiotic environment have had minimal impact on the communication component of the EOD and selective forces of a biotic nature – imposed by electroreceptive predators, reproductive interference from heterospecific congeners, and sexual selection – may be important sources of diversifying selection on Gymnotus signals.
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TLDR
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TLDR
Differences in the EOD phenotype of the two studied taxa are due to the different EO auto-excitability, caused either by the different expression of a genetic repertoire of conductance in the electrocyte membrane or in the wall of the tubes forming the EO.
Electric organ discharges and near-field spatiotemporal patterns of the electromotive force in a sympatric assemblage of Neotropical electric knifefish
TLDR
The functional significance of diversity in the ht-EOD waveforms and near-field spatiotemporal patterns of the electromotive force among a species-rich sympatric community of Brachyhypopomus from the upper Amazon is discussed.
Electric signals and species recognition in the wave-type gymnotiform fish Apteronotus leptorhynchus
TLDR
Gymnotiformes are South American weakly electric fish that produce weak electric organ discharges (EOD) for orientation, foraging and communication purposes and it is found that the EOD waveform is a more specific cue than EOD frequency, which shows large overlap across species.
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It is shown here that predation pressure on neotropical, weakly electric fish seems to have selected for greater signal complexity, by favouring characters that have enabled further signal elaboration by sexual selection.
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