Fishes are the most diverse group of vertebrates, are key players in aquatic ecosystems, provide a diverse set of ecosystem services, and are declining faster than any other animal groups on Earth. We study their ecology, evolution and conservation. We work with variation in traits and genes within populations and all the way up to the diversity of species assemblages, their change through time and the ecosystem consequences of such change. We are particularly interested in understanding the evolution of endemic species diversity, such as the radiations of cichlid fish in African lakes and the radiations of fish in the lakes around the Alps. We are a division of the IEE and a research group at the Eawag Department Fish Ecology and Evolution in Kastanienbaum (evolutionary biodiversity dynamics group), both led by Ole Seehausen. Our work is motivated by the necessity to integrate ecology, evolutionary biology and conservation biology and the need to develop such synthesis from within a societal framework of diversity, equity and justice. Researchers in the department of vertebrates at the Natural History Museum Bern, NMBE, are affiliated with our IEE division.