01832nas a2200169 4500008004100000245008100041210006900122260001300191300001400204490000800218520128400226100002501510700002901535700002201564700002301586856005301609 2016 eng d00aElectric fish genomics: progress, prospects, and new tools for neuroethology0 aElectric fish genomics progress prospects and new tools for neur bElsevier a259–2720 v1103 a

Electric fish have served as a model system in biology since the 18th century, providing deep insight into the nature of bioelectrogenesis, the molecular structure of the synapse, and brain circuitry underlying complex behavior. Neuroethologists have collected extensive phenotypic data that span biological levels of analysis from molecules to ecosystems. This phenotypic data, together with genomic resources obtained over the past decades, have motivated new and exciting hypotheses that position the weakly electric fish model to address fundamental 21st century biological questions. This review article considers the molecular data collected for weakly electric fish over the past three decades, and the insights that data of this nature has motivated. For readers relatively new to molecular genetics techniques, we also provide a table of terminology aimed at clarifying the numerous acronyms and techniques that accompany this field. Next, we pose a research agenda for expanding genomic resources for electric fish research over the next 10 years. We conclude by considering some of the exciting research prospects for neuroethology that electric fish genomics may offer over the coming decades, if the electric fish community is successful in these endeavors.

1 aPitchers, William, R1 aConstantinou, Savvas, J.1 aLosilla, Mauricio1 aGallant, Jason, R. uhttps://doi.org/10.1016/j.jphysparis.2016.10.00303057nas a2200313 4500008004100000022001300041245015100054210006900205260001600274520202800290653002802318653002002346653002802366653001202394653001402406100002202420700001702442700002702459700001502486700001802501700002302519700002102542700002602563700002402589700002302613700002002636700002102656856006602677 2017 eng d a0928425700aIntragenus (Campylomormyrus) and intergenus hybrids in mormyrid fish: physiological and histological investigations of the electric organ ontogeny0 aIntragenus Campylomormyrus and intergenus hybrids in mormyrid fi cJan-01-20173 a

African weakly electric mormyrid fish show a high diversity of their electric organ discharge (EOD) both across and within genera. Thanks to a recently developed technique of artificial reproduction in mormyrid fish, we were able to perform hybridizations between different genera and within one genus (Campylomormyrus). The hybrids of intergenus hybridizations exhibited different degrees of reduced survival related to the phylogenetic distance of the parent species: hybrids of the crosses between C. rhynchophorus and its sister genus Gnathonemus survived and developed normally. Hybrids between C. rhynchophorus and a Mormyrus species (a more basal clade compared to Campylomormyrus s) survived up to 42 days and developed many malformations, e.g., at the level of the unpaired fins. Hybrids between C. numenius and Hippopotamyrus pictus (a derived clade, only distantly related to Campylomormyrus) only survived for two days during embryological development. Seven different hybrid combinations among five Campylomormyrus species (C. tamandua, C. compressirostris, C. tshokwe, C. rhynchophorus, C. numenius) were performed. The aim of the hybridizations was to combine species with (1) either caudal or rostral position of the main stalk innervating the electrocytes in the electric organ and (2) short, median or long duration of their EOD. The hybrids, though they are still juveniles, show very interesting features concerning electrocyte geometry as well as EOD form and duration: the caudal position of the stalk is prevailing over the rostral position, and the penetration of the stalk is dominant over the non-penetrating feature (in the Campylomormyrus hybrids); in the hybrid between C. rhynchophorus and Gnathonemus petersii it is the opposite. When crossing species with long and short EODs, it is always the long duration EOD that is expressed in the hybrids. The F1-Hybrids of the cross C. tamandua x C. compressirostris are fertile: viable F2-fish could be obtained with artificial reproduction

10aArtificial reproduction10aCampylomormyrus10aElectric organ ontogeny10aHybrids10amormyrids1 aKirschbaum, Frank1 aNguyen, Linh1 aBaumgartner, Stephanie1 aChi, Linda1 aWolfart, Rene1 aElarbani, Khouloud1 aEppenstein, Hari1 aKorniienko, Yevheniia1 aGuido-Böhm, Lilian1 aMamonekene, Victor1 aVater, Marianne1 aTiedemann, Ralph uhttp://linkinghub.elsevier.com/retrieve/pii/S092842571730003702502nas a2200145 4500008004100000022001300041245011400054210006900168260001600237520196500253100002202218700002902240700002102269856006602290 2016 eng d a0928425700aObject discrimination through active electrolocation: Shape recognition and the influence of electrical noise0 aObject discrimination through active electrolocation Shape recog cJan-12-20163 a

The weakly electric fish Gnathonemus petersii can recognise objects using active electrolocation. Here, we tested two aspects of object recognition; first whether shape recognition might be influenced by movement of the fish, and second whether object discrimination is affected by the presence of electrical noise from conspecifics. (i) Unlike other object features, such as size or volume, no parameter within a single electrical image has been found that encodes object shape. We investigated whether shape recognition might be facilitated by movement-induced modulations (MIM) of the set of electrical images that are created as a fish swims past an object. Fish were trained to discriminate between pairs of objects that either created similar or dissimilar levels of MIM of the electrical images. As predicted, the fish were able to discriminate between objects up to a longer distance if there was a large difference in MIM between the objects than if there was a small difference. This supports an involvement of MIMs in shape recognition but the use of other cues cannot be excluded. (ii) Electrical noise might impair object recognition if the noise signals overlap with the EODs of an electrolocating fish. To avoid jamming, we predicted that fish might employ pulsing strategies to prevent overlaps. To investigate the influence of electrical noise on discrimination performance, two fish were tested either in the presence of a conspecific or of playback signals and the electric signals were recorded during the experiments. The fish were surprisingly immune to jamming by conspecifics: While the discrimination performance of one fish dropped to chance level when more than 22% of its EODs overlapped with the noise signals, the performance of the other fish was not impaired even when all its EODs overlapped. Neither of the fish changed their pulsing behaviour, suggesting that they did not use any kind of jamming avoidance strategy.

1 aSchumacher, Sarah1 ade Perera, Theresa, Burt1 avon der Emde, G. uhttp://linkinghub.elsevier.com/retrieve/pii/S092842571630030401997nas a2200229 4500008004100000022001300041245008100054210006900135260001600204520128400220653001101504653001801515653001901533653001301552653002001565653001601585100002601601700002901627700002201656700002301678856006601701 2016 eng d a0928425700aElectric Fish Genomics: Progress, Prospects, and New Tools for Neuroethology0 aElectric Fish Genomics Progress Prospects and New Tools for Neur cJan-10-20163 a

Electric fish have served as a model system in biology since the 18th century, providing deep insight into the nature of bioelectrogenesis, the molecular structure of the synapse, and brain circuitry underlying complex behavior. Neuroethologists have collected extensive phenotypic data that span biological levels of analysis from molecules to ecosystems. This phenotypic data, together with genomic resources obtained over the past decades, have motivated new and exciting hypotheses that position the weakly electric fish model to address fundamental 21st century biological questions. This review article considers the molecular data collected for weakly electric fish over the past three decades, and the insights that data of this nature has motivated. For readers relatively new to molecular genetics techniques, we also provide a table of terminology aimed at clarifying the numerous acronyms and techniques that accompany this field. Next, we pose a research agenda for expanding genomic resources for electric fish research over the next 10 years. We conclude by considering some of the exciting research prospects for neuroethology that electric fish genomics may offer over the coming decades, if the electric fish community is successful in these endeavors.

10aCRISPR10aelectric fish10agenome editing10agenomics10atranscriptomics10atransgenics1 aPitchers, William, R.1 aConstantinou, Savvas, J.1 aLosilla, Mauricio1 aGallant, Jason, R. uhttp://linkinghub.elsevier.com/retrieve/pii/S092842571630007903440nas a2200373 4500008004100000020001400041245016600055210006900221260001200290300001200302490000800314520221100322653002302533653002602556653002702582653002902609653002802638653001602666653003602682653002402718653001802742653002302760653002702783653002802810653002202838653001902860653002602879653001502905100002402920700002502944700002202969700002102991856005403012 2008 eng d a0928-425700aPetrocephalus of Odzala offer insights into evolutionary patterns of signal diversification in the Mormyridae, a family of weakly electrogenic fishes from Africa0 aPetrocephalus of Odzala offer insights into evolutionary pattern cJul-Nov a322-3390 v1023 a

Electric signals of mormyrid fishes have recently been described from several regions of Africa. Members of the Mormyridae produce weak electric organ discharges (EODs) as part of a specialized electrosensory Communication and orientation system. Sympatric species often express distinctive EODs, which may contribute to species recognition during mate choice in some lineages. Striking examples of interspecific EOD variation within assemblages have been reported for two monophyletic radiations: the Paramormyrops of Gabon and the Campylomormyrus of Lower Congo. Here, we describe a speciose assemblage of Petrocephalus in the Lekoli River system of Odzala National Park, Republic of Congo. This widespread genus comprises the Subfamily (Petrocephalinae) that is the Sister group to all other mormyrids (Mormyrinae). Eleven Petrocephalus species were collected in Odzala, five of which are not described taxonomically. We quantify EOD variation within this assemblage and show that all eleven species produce EOD waveforms of brief duration (species means range from 144 to 663 mu s) compared to many other mormyrids. We also present reconstructed phylogenetic relationships among species based on cytochrome b sequences. Discovery of the Odzala assemblage greatly increases the number of Petrocephalus species for which EODs and DNA sequence data are available, permitting a first qualitative comparison between mormyrid Subfamilies of the divergence patterns that have been described within lineages. We find that the Petrocephalus assemblage in Odzala is not a monophyletic radiation. Genetic divergence among Petrocephalus species often appears higher than among Paramormyrops or Campylomormyrus species. In contrast, results of this study and others Suggest that Petrocephalus may generally exhibit less interspecific EOD divergence, as well as smaller sex differences in EOD waveforms, compared to Paramormyrops and Campylomormyrus. We discuss possible causes and consequences of EOD diversification patterns observed within mormyrid subfamilies as a framework for future comparative studies of signal evolution using this emerging model system. (c) 2008 Elsevier Ltd. All rights reserved.

10aadaptive radiation10acommunication signals10aelectric organ anatomy10aelectric organ discharge10aelectrosensory modality10afood-habits10agnathonemus-petersii mormyridae10amolecular evolution10apetrocephalus10apollimyrus-isidori10ariverine species flock10asexual signal evolution10asexual-dimorphism10aspecies marker10atype npp electrocytes10awave-forms1 aLavoué, Sébastien1 aArnegard, Matthew, E1 aSullivan, John, P1 aHopkins, Carl, D u https://doi.org/10.1016/j.jphysparis.2008.10.00301778nas a2200169 4500008004100000022001300041245015100054210006900205260001100274300001400285490000800299520118000307100002701487700002201514700002101536856005101557 2008 eng d a0928425700aAdaptive radiation in the Congo River: An ecological speciation scenario for African weakly electric fish (Teleostei; Mormyridae; Campylomormyrus)0 aAdaptive radiation in the Congo River An ecological speciation s c7/2008 a340 - 3460 v1023 a

he ultimate aim of this study is to better understand the diversification of African weakly electric fish in the Congo River. Based on a robust phylogenetic hypothesis we examined the radiation within the mor- myrid genus Campylomormyrus. Morphological traits relevant for the divergence between the identified species were detected. Among them, the variation in the shape of the trunk-like elongated snout sug- gested the presence of different trophic specializations. Furthermore, the chosen model taxon, the genus Campylomormyrus, exhibits a wide diversity of electric organ discharge (EOD) waveforms. A comparison of EOD waveform types and phylogenetic relationships showed major differences in EOD between closely related species. This indicates that the EOD might function as a reproductive isolation mechanism. In con- clusion, we provide a plausible scenario of an adaptive radiation triggered by sexual selection and assor- tative mating based on EOD characteristics, but caused by a divergent selection on the feeding apparatus. These findings point towards an adaptive radiation of at least some Campylomormyrus species occurring in the Lower Congo River.

1 aFeulner, Philine, G.D.1 aKirschbaum, Frank1 aTiedemann, Ralph uhttps://mormyrids.efishgenomics.com/en/node/32