Thresholds and the species–area relationship: a synthetic analysis of habitat island datasets

Conservation Biogeography and Macroecology Programme, School of Geography and the Environment, University of Oxford, Oxford OX1 3QY, UK, Departamento de Cîencias Agr arias – CITAA, Azorean Biodiversity Group, Universidade dos Ac ores, Angra do Hero ısmo, Pico da Urze, 9700-042 Terceira, Ac ores, Portugal, Department of Biogeography, BayCEER, University of Bayreuth, Bayreuth D-95447, Germany, Department of Biological Applications and Technology, University of Ioannina, Ioannina 45100, Greece, Department of Ecology and Taxonomy, Faculty of Biology, National and Kapodistrian University, Athens GR-15784, Greece, Department of Biology, Center for Macroecology, Evolution and Climate, University of Copenhagen, Copenhagen Ø DK-2100, Denmark