In the Fish Evolutionary Ecology Group, we focus on evolutionary ecology in order to identify how ecological factors shape evolutionary trajectories and how evolutionary adaptations and constraints modify ecological traits. We combine fieldwork with controlled laboratory experiments and mesocosms using behavioural, genetic, histological and physiological approaches. Using freshwater fish as our study models, we investigate the evolution of ageing and its life history consequences; coevolution in brood parasites; the role of invasive species in rapid evolution; sexual selection and mating system evolution and their roles in diversification; and mechanisms of (fish) embryo adaptations to extreme environments. Our primary study organisms are bitterling fishes (Rhodeus), cuckoo catfish (Synodontis multipunctatus/grandiops) and African annual fishes (Nothobranchius).