1. Dept of Biological and Environmental Science; Univ. of Jyväskylä; Finland
2. Plant Biology and Ecology (Botany), Fac. of Science and Technology; Univ. of the Basque Country (UPV/EHU); Bilbao Spain
3. Centre for Biodiversity Dynamics, Dept of Biology; Norwegian Univ. of Science and Technology; NO-7491 Trondheim Norway
4. Dept of Statistical Science; Duke University; Durham USA
5. Natural History Museum; Univ. of Jyväskylä; Finland
6. Dept of Biosciences; Univ. of Helsinki; Finland