Mate choice and sperm competition in toads

Sexual selection is a pervasive force of evolution, shaping life-history characteristics such as morphology, physiology and behaviour. Despite a large body of research, our knowledge on the nature, costs, benefits and genetics of its mechanisms has remained sporadic. We will investigate two mechanisms of sexual selection, mate choice and sperm competition in the common toad, Bufo bufo. By applying recently proposed methodologies, we will be able to appropriately address central questions of sexual selection theory. Our focus will be on the detailed structure of mating preferences, on the relative importance of direct and indirect benefits in the evolution of mate choice and on gamete-level interactions representing the last step of prezygotic mate choice. We will also investigate currently largely unknown behavioural mechanisms like the behaviours available to females for alleviating consequences of sexual coercion or the behavioural patterns leading to and being consequences of sperm competition. Finally, we will study proximate mechanisms of the determination of offspring quality and of hybridization avoidance in external fertilizers. These investigations will help uncover evolutionary processes shaping sexual behaviour in the common toad and will test recently proposed hypotheses in relation to the reproductive biology of anuran amphibians in general. Further, by addressing and rigorously testing several predictions of sexual selection theory, they will significantly contribute to the advance of evolutionary biology.

Sexual selection is a pervasive force of evolution, shaping life-history characteristics such as morphology, physiology and behaviour. Despite a large body of research, our knowledge on the nature, costs, benefits and genetics of its mechanisms has remained sporadic. We will investigate two mechanisms of sexual selection, mate choice and sperm competition in the common toad, Bufo bufo. By applying recently proposed methodologies, we will be able to appropriately address central questions of sexual selection theory. Our focus will be on the detailed structure of mating preferences, on the relative importance of direct and indirect benefits in the evolution of mate choice and on gamete-level interactions representing the last step of prezygotic mate choice. We will also investigate currently largely unknown behavioural mechanisms like the behaviours available to females for alleviating consequences of sexual coercion or the behavioural patterns leading to and being consequences of sperm competition. Finally, we will study proximate mechanisms of the determination of offspring quality and of hybridization avoidance in external fertilizers. These investigations will help uncover evolutionary processes shaping sexual behaviour in the common toad and will test recently proposed hypotheses in relation to the reproductive biology of anuran amphibians in general. Further, by addressing and rigorously testing several predictions of sexual selection theory, they will significantly contribute to the advance of evolutionary biology.