| A major question in evolutionary biology is how species evolve under selection. Specifically, evolution can proceed under natural and sexual selection. Sexual selection is in general imposed by female choices for mates. Females often have preferences for male phenotypes that do not exist. They may want exaggerated traits (long tails, bright colors), or combination of traits (male fish with large bodies and small fins). Sexual selection may thus hit a dead end, if there is no available variation in male traits. Hybridization, the interbreeding of two species, can provide new variation in traits for selection to act on. Here I propose to investigate the dynamic interaction between female mate preferences and male phenotypes after hybridization. Much work has been done on evolution after hybridization through natural selection, but the question of how female mate preferences evolve after hybridization has largely been ignored. I will investigate this empirically in swordtail fish, an established model system in sexual selection research. I will also study this question through mathematical modelling. This dual approach will ensure that both theoretical and empirical knowledge will advance hand in hand. |
