Franziska Schaedelin KLIVV Title Sexy sand castles on the bottom of Lake Tanganyika Abstract The evolution of secondary sexual characters and their maintenance is a prime question in the study of sexual selection. Conspicuous secondary sexual traits are particularly prominent in species with lek mating systems. Since females do not obtain direct benefits from mating partners, lek systems are highly suitable to study sexual selection mechanisms. In the lekking Lake Tanganyika cichlid Cyathopharynx furcifer the most peculiar male secondary sexual trait is the building of sand craters. Although craters do not serve any breeding function, males spend the majority of their time building and defending these structures. There is little variability in crater shape, but very large variance in size. Experiments demonstrate that craters are an individual characteristic of their owners and should be addressed as extended phenotypes of males. Field observations suggested a signalling value of this costly non-bodily ornament. In a field experiment, we disentangled male quality and crater characteristics by manipulating craters. Randomly assigned craters were destroyed and rebuilt by the experimenter either with smaller, larger or same size as the original. With the help of underwater video surveillance, we investigated the reaction of crater-owners and change in female preference. Unexpectedly, crater-owners rebuilt their craters to the original sizes immediately independent of the crater manipulation. Additionally, crater size had less effect on female mating preference than male building behaviour. These results were confirmed in an interactive mate choice experiment in the laboratory. Apart from female preference, other factors may influence crater shape and size. Possibly, crater size is the outcome of the constructor’s balance between costs of more intense male-male-interactions and increased attraction to females.   Persönliches 1974 geboren in Bern (CH) Ausbildung Feb 2005- Post-doc: “Habitat selection and male mating success in colonial fish” with Dr. R. Wagner am KLIVV Okt 2004 - Jan 2005 Post-doc Universität Bern/Behavioural Ecology Juni 2004 - Sept 2004 Projektmitarbeiterin der Universität Basel: “Ecological implications of sheep pasturing, climate change and nitrogen deposition on alpine grassland" Dez 2000 - Mai 2004 Dissertation in Verhaltensökologie an der Universität Bern (Behavioural Ecology group): “The signalling value of an extended phenotype: Construction of sexy sand craters in Cyathopharynx furcifer” Supervisor: Prof. Dr. M. Taborsky 2000 Oct 23rd Diplom der Universität Basel, Hauptfach Zoologie, Nebenfächer Botanik und Geographie 1999 - 2000 Diplomarbeit am Institut für Evolutionäre und Ökologische Wissenschaften der Universität Leiden, Niederlande: “Environmental conditions favouring a sex ratio distortion in Drosophila” 1994 - 1999 Biologie I Studium an der Universität Basel 1986 - 1994 Gymnasium Bäumlihof, Basel Nebenbeschäftigungen Sept 2002 - Sept 2003 Präsidentin und Troubleshooter des Organisationskomittees: „9th PhD Meeting of European Students in Evolutionary Biology” Sommer 2000 Feldassistenz bei den Projekten “sexual and asexual reproduction system of Venturia canescens” in Frankreich und Epilobium Projekt 2000, Universität Basel Frühjahr 1998 Gymnasium Bäumlihof, Untericht in Biologie und Geographie 1997 - 1999 Mitglied des StudentInnen Rates und der Fachschaft Biologie der Universität Basel Herbst 1997 10-wöchiges Praktikum im Ökobüro life-science, Basel 1995 - 1997 Inventar beim Basler Naturatlas Sommer 1997 TBA- course (Tropical Biology Association): Tropical Biology and Conservation in the national park Kibale forest, Uganda, Africa   Conference contributions 2005 Poster: ESEB Krakau 2005 2004 Presentation: International Society for Behavioural Ecology, Jyväskylä, Finland and European Conference on Behavioural Ecology 2003 Poster: National biology conference of Switzerland: Biology 03 2002 Talk: PhD Meeting in Lohja, Finnland 2002 National biology conference of Switzerland: Biology 02, Second poster prize 2001 International Ethology Conference in Tübingen: Poster Prize of the behavioural ecology   Contact: Franziska Schaedelin franziska.schaedelin@esh.unibe.ch