1. Biodiversity and Macroecology Group, Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK
2. NERC Centre for Ecology and Hydrology, Crowmarsh Gifford, Wallingford, Oxfordshire OX10 8BB, UK
3. Stockholm Environment Institute and Centre for Terrestrial Carbon Dynamics (York Centre), Environment Department, Grimston House, University of York, York YO10 5DD, UK
4. Department of Ecology and Evolutionary Biology, University of Tennessee, Knoxville, TN 37996-1601, USA