@misc{AmenNagelHedtetal.2020, author = {Amen, Rahma and Nagel, Rebecca and Hedt, Maximilian and Kirschbaum, Frank and Tiedemann, Ralph}, title = {Morphological differentiation in African weakly electric fish (genus Campylomormyrus) relates to substrate preferences}, series = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, journal = {Zweitver{\"o}ffentlichungen der Universit{\"a}t Potsdam : Mathematisch-Naturwissenschaftliche Reihe}, number = {3}, issn = {1866-8372}, doi = {10.25932/publishup-51871}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-518714}, pages = {13}, year = {2020}, abstract = {Under an ecological speciation scenario, the radiation of African weakly electric fish (genus Campylomormyrus) is caused by an adaptation to different food sources, associated with diversification of the electric organ discharge (EOD). This study experimentally investigates a phenotype-environment correlation to further support this scenario. Our behavioural experiments showed that three sympatric Campylomormyrus species with significantly divergent snout morphology differentially react to variation in substrate structure. While the short snout species (C. tamandua) exhibits preference to sandy substrate, the long snout species (C. rhynchophorus) significantly prefers a stone substrate for feeding. A third species with intermediate snout size (C. compressirostris) does not exhibit any substrate preference. This preference is matched with the observation that long-snouted specimens probe deeper into the stone substrate, presumably enabling them to reach prey more distant to the substrate surface. These findings suggest that the diverse feeding apparatus in the genus Campylomormyrus may have evolved in adaptation to specific microhabitats, i.e., substrate structures where these fish forage. Whether the parallel divergence in EOD is functionally related to this adaptation or solely serves as a prezygotic isolation mechanism remains to be elucidated.}, language = {en} } @article{AmenNagelHedtetal.2020, author = {Amen, Rahma and Nagel, Rebecca and Hedt, Maximilian and Kirschbaum, Frank and Tiedemann, Ralph}, title = {Morphological differentiation in African weakly electric fish (genus Campylomormyrus) relates to substrate preferences}, series = {Evolutionary Ecology}, volume = {34}, journal = {Evolutionary Ecology}, number = {3}, publisher = {Springer Science}, address = {Dordrecht}, issn = {0269-7653}, doi = {10.1007/s10682-020-10043-3}, pages = {427 -- 437}, year = {2020}, abstract = {Under an ecological speciation scenario, the radiation of African weakly electric fish (genus Campylomormyrus) is caused by an adaptation to different food sources, associated with diversification of the electric organ discharge (EOD). This study experimentally investigates a phenotype-environment correlation to further support this scenario. Our behavioural experiments showed that three sympatric Campylomormyrus species with significantly divergent snout morphology differentially react to variation in substrate structure. While the short snout species (C. tamandua) exhibits preference to sandy substrate, the long snout species (C. rhynchophorus) significantly prefers a stone substrate for feeding. A third species with intermediate snout size (C. compressirostris) does not exhibit any substrate preference. This preference is matched with the observation that long-snouted specimens probe deeper into the stone substrate, presumably enabling them to reach prey more distant to the substrate surface. These findings suggest that the diverse feeding apparatus in the genus Campylomormyrus may have evolved in adaptation to specific microhabitats, i.e., substrate structures where these fish forage. Whether the parallel divergence in EOD is functionally related to this adaptation or solely serves as a prezygotic isolation mechanism remains to be elucidated.}, language = {en} } @article{LamannaKirschbaumTiedemann2014, author = {Lamanna, Francesco and Kirschbaum, Frank and Tiedemann, Ralph}, title = {De novo assembly and characterization of the skeletal muscle and electric organ transcriptomes of the African weakly electric fish Campylomormyrus compressirostris (Mormyridae, Teleostei)}, series = {Molecular ecology resources}, volume = {14}, journal = {Molecular ecology resources}, number = {6}, publisher = {Wiley-Blackwell}, address = {Hoboken}, issn = {1755-098X}, doi = {10.1111/1755-0998.12260}, pages = {1222 -- 1230}, year = {2014}, abstract = {African weakly electric fishes (Mormyridae) underwent an outstanding adaptive radiation (about 200 species), putatively owing to their ability to communicate through species-specific weak electric signals. The electric organ discharge (EOD) is produced by muscle-derived electrocytes organized in piles to form an electric organ. Despite the importance of this trait as a prezygotic isolation mechanism, genomic resources remained limited. We present here a first draft of the skeletal muscle and electric organ transcriptomes from the weakly electric fish species Campylomormyrus compressirostris, obtained using the Illumina HiSeq2000 sequencing technology. Approximately 6.8 Gbp of cDNA sequence data were produced from both tissues, resulting in 57268109 raw reads for the skeletal muscle and 46934923 for the electric organ, and assembled de novo into 46143 and 89270 contigs, respectively. About 50\% of both transcriptomes were annotated after protein databases search. The two transcriptomes show similar profiles in terms of Gene Ontology categories composition. We identified several candidate genes which are likely to play a central role in the production and evolution of the electric signal. For most of these genes, and for many other housekeeping genes, we were able to obtain the complete or partial coding DNA sequences (CDS), which can be used for the development of primers to be utilized in qRT-PCR experiments. We present also the complete mitochondrial genome and compare it to those available from other weakly electric fish species. Additionally, we located 1671 SSR-containing regions with their flanking sites and designed the relative primers. This study establishes a first step in the development of genomic tools aimed at understanding the role of electric communication during speciation.}, language = {en} }