Open AccessDissecting a potential spandrel of adaptive radiation: Body depth and pectoral fin ecomorphology coevolve in Lake Malawi cichlid fishes
Author(s) -
Hulsey Christopher D.,
Holzman Roi,
Meyer Axel
Publication year - 2018
Publication title -
ecology and evolution
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.17
H-Index - 63
ISSN - 2045-7758
DOI - 10.1002/ece3.4651
Subject(s) - pectoral girdle , cichlid , ecomorphology , biology , fish fin , adaptive radiation , coevolution , evolutionary biology , ecology , zoology , phylogenetic tree , anatomy , fish <actinopterygii> , fishery , biochemistry , habitat , gene
The evolution of body shape reflects both the ecological factors structuring organismal diversity as well as an organism's underlying anatomy. For instance, body depth in fishes is thought to determine their susceptibility to predators, attractiveness to mates, as well as swimming performance. However, the internal anatomy influencing diversification of body depth has not been extensively examined, and changes in body depth could arise as a by‐product of functional changes in other anatomical structures. Using an improved phylogenetic hypothesis for a diverse set of Lake Malawi cichlid fishes, we tested the evolutionary association between body depth and the height of the pectoral girdle. To refine the functional importance of the observed substantial correlation, we also tested the coevolution of pectoral girdle height and pectoral fin area. The extensive coevolution of these traits suggests body depth in fishes like the Lake Malawi cichlids could diverge simply as a by‐product of being tightly linked to ecomorphological divergence in other functional morphological structures like the pectoral fins.