02730nas a2200121   4500008004100000022001400041245006700055210006600122260001600188520231400204100002802518856006202546       2019                        eng d  a0022-111200aElectroreception, electrogenesis and electric signal evolution0 aElectroreception electrogenesis and electric signal evolution  cJun-03-20203 a<p>Electroreception, the capacity to detect external underwater electric fields with specialised receptors, is a phylogenetically widespread sensory modality in fishes and amphibians. In passive electroreception, a capacity possessed by c. 16% of fish species, an animal uses low‐frequency‐tuned ampullary electroreceptors to detect microvolt‐range bioelectric fields from prey, without the need to generate its own electric field. In active electroreception (electrolocation), which occurs only in the teleost lineages Mormyroidea and Gymnotiformes, an animal senses its surroundings by generating a weak (&lt;&thinsp;1 V) electric‐organ discharge (EOD) and detecting distortions in the EOD‐associated field using high‐frequency‐tuned tuberous electroreceptors. Tuberous electroreceptors also detect the EODs of neighbouring fishes, facilitating electrocommunication. Several other groups of elasmobranchs and teleosts generate weak (&lt;&thinsp;10 V) or strong (&gt;&thinsp;50&thinsp;V) EODs that facilitate communication or predation, but not electrolocation. Approximately 1.5% of fish species possess electric organs. This review has two aims. First, to synthesise our knowledge of the functional biology and phylogenetic distribution of electroreception and electrogenesis in fishes, with a focus on freshwater taxa and with emphasis on the proximate (morphological, physiological and genetic) bases of EOD and electroreceptor diversity. Second, to describe the diversity, biogeography, ecology and electric signal diversity of the mormyroids and gymnotiforms and to explore the ultimate (evolutionary) bases of signal and receptor diversity in their convergent electrogenic&ndash;electrosensory systems. Four sets of potential drivers or moderators of signal diversity are discussed. First, selective forces of an abiotic (environmental) nature for optimal electrolocation and communication performance of the EOD. Second, selective forces of a biotic nature targeting the communication function of the EOD, including sexual selection, reproductive interference from syntopic heterospecifics and selection from eavesdropping predators. Third, non‐adaptive drift and, finally, phylogenetic inertia, which may arise from stabilising selection for optimal signal‐receptor matching.</p>
1 aCrampton, William, G.R.  uhttps://onlinelibrary.wiley.com/doi/abs/10.1111/jfb.1392201327nas a2200133   4500008004100000245008100041210006900122300001200191490000600203520085700209100001601066700002801082856008301110       2006                        eng d00aA portable bio-amplifier for electric fish research: design and construction0 aportable bioamplifier for electric fish research design and cons  a295-2990 v43 a<p>The weak electric organ discharges (EODs) of gymnotiform knife fishes can be readily amplified with a wideband amplifier connected to submerged electrodes. The output from such an amplifier can then be monitored with audio speakers or digitized for subsequent analysis. Commercially available devices are expensive and usually require mains electrical power. Here we provide design notes and instructions for the construction and calibration of a cheap, portable, battery-powered, AC-coupled wideband bio-amplifier. This device was designed to allow electric fishes to be located in the field, and also to permit the relatively noise-free acquisition of EOD waveforms from specimens held in temporary captivity. This contribution is intended to encourage students of neotropical ichthyology to explore electric signaling in gymnotiform fishes.</p>
1 aWells, J.K.1 aCrampton, William, G.R.  uhttp://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-6225200600020001800749nas a2200229   4500008004100000022001400041245009800055210006900153260001200222300001400234490000800248100002600256700002400282700002100306700002500327700002800352700002200380700002300402700002400425700002200449856004800471       2010                        eng d  a1537-532300aSexual Signal Evolution Outpaces Ecological Divergence during Electric Fish Species Radiation0 aSexual Signal Evolution Outpaces Ecological Divergence during El  c09/2010  a335 - 3560 v1761 aArnegard, Matthew, E.1 aMcIntyre, Peter, B.1 aHarmon, Luke, J.1 aZelditch, Miriam, L.1 aCrampton, William, G.R.1 aDavis, Justin, K.1 aSullivan, John, P.1 aLavoué, Sébastien1 aHopkins, Carl, D.  uhttps://mormyrids.myspecies.info/en/node/26