Meeting Abstract

70.6  Thursday, Jan. 6  Can Pectoral Fin Locomotion Mediate Trophic Divergence in a Sister Species Pair of Malawi Cichlids? HULSEY, CD*; RUPP, MF; HOLLINGSWORTH JR, PR; Univ. of Tennessee chulsey@utk.edu

The unparalleled feeding diversity of Lake Malawi cichlids has long been recognized. However, the locomotory diversity associated with this feeding diversity is only now being explored. Using video recordings of fish in the wild in Lake Malawi, we examined differences in pectoral fin kinematics between feeding and freely swimming mbuna, or rock-dwelling, cichlids. We then conducted a morphological study of pectoral morphology on two species of Labeotropheus that have diversified along a habitat gradient within the lake. Finally, using video recordings taken of Labeotropheus swimming within the lake, we explored how divergence in pectoral fin morphology and mechanics influence pectoral fin kinematics and function when these two species feed. Locomotory divergence in these fish species provides a potentially ubiquitous mechanism for trophic niche partitioning in the most species rich lake in the world.