1. Department of Computer and Information Science, University of Konstanz, Fach 76, 78457 Konstanz, Germany
2. Faculty of Information Technology, Monash University, Melbourne, Australia
3. School of Design, Royal College of Arts, London, UK
4. Max-Planck-Institute for Ornithology, Radolfzell, Germany
5. Centre for the Advanced Study of Collective Behaviour, University of Konstanz, Konstanz, Germany
6. Department of Biology, University of Konstanz, Konstanz, Germany
7. MTA-ELTE Statistical and Biological Physics Research Group, Hungarian Academy of Sciences, Budapest, Hungary