1. Department of Animal Behaviour, University of Bielefeld, Postfach, Bielefeld, Germany
2. School of Natural Science and Psychology, Liverpool John Moores University, Liverpool, UK
3. College of Life and Environmental Sciences, University of Exeter, Penryn, UK
4. Centre for Research in Ecology, Evolution and Behaviour, Department of Life Sciences, University of Roehampton, London, UK
5. Organismal and Evolutionary Biology Research Programme, Faculty of Biological and Environmental Sciences, University of Helsinki, Helsinki, Finland
6. British Antarctic Survey, Cambridge, Cambridgeshire, UK
7. Department of Biosciences, Swansea University, Swansea, UK