1. Department of Collective Behaviour Max Planck Institute of Animal Behavior Konstanz Germany
2. Centre for the Advanced Study of Collective Behaviour University of Konstanz Konstanz Germany
3. Department of Biology University of Konstanz Konstanz Germany
4. Institute of Biology University of Graz Graz Austria
5. Lake Tanganyika Research Unit, Department of Fisheries Ministry of Fisheries and Livestock Mpulungu Zambia