The extensive radiations of cichlid fishes in the lakes of East Africa are an ideal system for studying the ecological and genetic factors that promote speciation. This project will examine whether the evolution of new sex chromosomes, in combination with linked color polymorphisms, has been important in the speciation of Lake Malawi cichlids. Molecular markers will be used to genetically map the genes controlling sex determination and color polymorphisms in the highly polymorphic genus Metriaclima. Phylogenetic analysis will determine whether recently evolved color patterns are linked to the evolution of new sex chromosomes.
These data will provide key empirical data to evaluate whether genetic conflict over sex ratio is important to the spectacular radiation of these fishes, and by extension to the evolution of many other animal species. The project will also provide training opportunities for undergraduates in the form of well-defined research projects for summer internships and senior theses. The highly interdisciplinary nature of the research program will provide a fertile training ground for graduate and postdoctoral research. The results of the research will be communicated to cichlid aquarists and the general public through an existing www site.