A geographical cline in craniofacial morphology across populations of Mesoamerican lake-dwelling fishes.

ABSTRACT: Together, the complex geological history and climatic diversity of Mesoamerica create a rich source of biodiversity from which evolutionary processes can be studied. Here, we discuss highly divergent morphs of lake-dwelling fishes distributed across Mexico and Central America, originally recognized as members of different genera (Astyanax and "Bramocharax"). Recent phylogenetic studies, however, suggest these morphs group within the same genus and readily hybridize. Despite genetic similarities, Bramocharax morphs exhibit stark differences in cranial shape and dentition. We investigated the evolution of several cranial traits that vary across morphs collected from four lakes in Mexico and Nicaragua and discovered an ecomorphological cline from northern to southern lakes. Northern populatio

SUBMITTER: Powers AK 

PROVIDER: S-EPMC7372644 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature