Abstract
In Lake Tanganyika, several lineages of cichlids have diversified into 200 species. Tribe Tropheini contains the greatest richness of herbivorous species that are classified into four ecomorphs: grazers, browsers, suckers, and pickers. All of these ecomorphs coexist on littoral rocky shores. To reveal the differences among species within ecomorphs, we analysed fish shape and functional morphology related to feeding habits, using geometric morphometrics, and measured intestine length. Furthermore, we tested the relationship between genetic and morphological distances. As a result, diversities of functional morphology among ecomorphs, and among species within ecomorphs, were revealed. In grazers, morphological diversity was greatest in jaws and the opening direction of mouth, suggesting that these species have adapted to feed on various substrata. In browsers, intestine length varied among species, indicating that this ecomorph consists of species with various specializations in herbivory. Morphological divergence was found only in the mandible and occlusal facet in grazers. No clear relation was found between morphological and phylogenetic distances in browsers, which are a polyphyletic group, indicating that their traits were acquired by convergence in multiple lineages. Our data suggest that the observed morphological variation among species enable sympatric species to separate their feeding niches.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
