TY  - JOUR
A1  - Nagel, Rebecca
A1  - Kirschbaum, Frank
A1  - Engelmann, Jacob
A1  - Hofmann, Volker
A1  - Pawelzik, Felix
A1  - Tiedemann, Ralph
T1  - Male-mediated species recognition among African weakly electric fishes
JF  - Royal Society Open Science
N2  - Effective communication among sympatric species is often instrumental for behavioural isolation, where the failure to successfully discriminate between potential mates could lead to less fit hybrid offspring. Discrimination between con- and heterospecifics tends to occur more often in the sex that invests more in offspring production, i.e. females, but males may also mediate reproductive isolation. In this study, we show that among two Campylomormyrus Africanweakly electric fish species, males preferentially associate with conspecific females during choice tests using live fish as stimuli, i.e. when all sensory modalities potentially used for communication were present. We then conducted playback experiments to determine whether the species-specific electric organ discharge (EOD) used for electrocommunication serves as the cue for this conspecific association preference. Interestingly, only C. compressirostris males associated significantly more with the conspecific EOD waveform when playback stimuli were provided, while no such association preference was observed in C. tamandua males. Given our results, the EOD appears to serve, in part, as a male-mediated pre-zygotic isolation mechanism among sympatric species. However, the failure of C. tamandua males to discriminate between con- and heterospecific playback discharges suggests that multiple modalities may be necessary for species recognition in some African weakly electric fish species.
KW  - Campylomormyrus
KW  - communication
KW  - electric fishes
KW  - pre-zygotic isolation
KW  - species recognition
Y1  - 2018
U6  - https://doi.org/10.1098/rsos.170443
SN  - 2054-5703
VL  - 5
IS  - 2
PB  - Royal Society
CY  - London
ER  - 
TY  - JOUR
A1  - Paul, Christiane
A1  - Mamonekene, Victor
A1  - Vater, Marianne
A1  - Feulner, Philine G. D.
A1  - Engelmann, Jacob
A1  - Tiedemann, Ralph
A1  - Kirschbaum, Frank
T1  - Comparative histology of the adult electric organ among four species of the genus Campylomormyrus (Teleostei: Mormyridae)
JF  - Journal of comparative physiology : A, Neuroethology, sensory, neural, and behavioral physiology
N2  - The electric organ (EO) of weakly electric mormyrids consists of flat, disk-shaped electrocytes with distinct anterior and posterior faces. There are multiple species-characteristic patterns in the geometry of the electrocytes and their innervation. To further correlate electric organ discharge (EOD) with EO anatomy, we examined four species of the mormyrid genus Campylomormyrus possessing clearly distinct EODs. In C. compressirostris, C. numenius, and C. tshokwe, all of which display biphasic EODs, the posterior face of the electrocytes forms evaginations merging to a stalk system receiving the innervation. In C. tamandua that emits a triphasic EOD, the small stalks of the electrocyte penetrate the electrocyte anteriorly before merging on the anterior side to receive the innervation. Additional differences in electrocyte anatomy among the former three species with the same EO geometry could be associated with further characteristics of their EODs. Furthermore, in C. numenius, ontogenetic changes in EO anatomy correlate with profound changes in the EOD. In the juvenile the anterior face of the electrocyte is smooth, whereas in the adult it exhibits pronounced surface foldings. This anatomical difference, together with disparities in the degree of stalk furcation, probably contributes to the about 12 times longer EOD in the adult.
KW  - Mormyridae
KW  - Campylomormyrus
KW  - Electric organ discharge
KW  - Electrocyte geometry
KW  - Electric organ ontogeny
Y1  - 2015
U6  - https://doi.org/10.1007/s00359-015-0995-6
SN  - 0340-7594
SN  - 1432-1351
VL  - 201
IS  - 4
SP  - 357
EP  - 374
PB  - Springer
CY  - New York
ER  -