1. Department of Ecology and Genetics, University of Oulu, Pentti Kaiteran Katu, Oulu, Finland
2. Estonian University of Life Sciences, Friedrich Reinhold Kreutzwaldi, Tartu, Estonia
3. Organization for Programs in Environmental Sciences, University of Tokyo, Meguro-ku, Tokyo, Japan
4. Section of Ecology, Department of Biology, University of Turku, Turku, Finland