Mate choice and sexual selection: what have we learnt from studies of Nordic gobies?

Sexual selection has been a central focus in Nordic goby research during the last two decades. This talk reviews the history of Nordic sexual selection work with gobies. A central focus is on how (Nordic) gobies have beensuccessfully used as models to test phenomena and processes of wide-ranging ecological and evolutionary relevance. For instance, gobies have been instrumental in understanding how natural and man-made variation in the environment affects mate choice and sexual selection. In short, predators, nest excess and eutrophication has been shown to relax sexual selection, through effects on female mate choice or male-male competition. Work on mate- sampling patterns, an important but understudied aspect of sexual selection, has revealed that fish may use simpler decision rules than seem to be the case with birds. While considerable research efforts have been directed at testing how male size affects mate choice and competition, Nordic gobies have not been extensively used as models in research on visual ornamentation. This may partly reflect the fact that most Nordic goby species are modestly ornamented. However, goby research has recently provided important insights into the function of female visual ornamentation. As with 4 any model system, the Nordic goby species are not ideally suited for all purposes; it is, for instance, not easy to study intergenerational processes. Nonetheless, research by the Nordic goby labs has been important in enhancing our understanding of sexual selection in animals at a general level. I argue that Nordic gobies, and gobies in general, still have great potential as models to test central, unresolved, questions in sexual selection.