TY  - JOUR
A1  - Amen, Rahma
A1  - Nagel, Rebecca
A1  - Hedt, Maximilian
A1  - Kirschbaum, Frank
A1  - Tiedemann, Ralph
T1  - Morphological differentiation in African weakly electric fish (genus Campylomormyrus) relates to substrate preferences
JF  - Evolutionary Ecology
N2  - 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.
KW  - ecological speciation
KW  - feeding behaviour
KW  - electric fish
KW  - trophic apparatus
KW  - evolutionary ecology
Y1  - 2020
U6  - https://doi.org/10.1007/s10682-020-10043-3
SN  - 0269-7653
SN  - 1573-8477
VL  - 34
IS  - 3
SP  - 427
EP  - 437
PB  - Springer Science
CY  - Dordrecht
ER  -