1. School of the Environment, University of Dundee, Dundee DD1 4HN, Scotland, UK.
2. Department of Botany, Program in Ecology, and Berry Biodiversity Conservation Center, University of Wyoming, Laramie, WY 82071, USA.
3. QUEST, Department of Earth Sciences, University of Bristol, Bristol BS8 1RJ, UK.
4. Grantham Institute for Climate Change and Division of Biology, Imperial College London, London SW7 2AZ, UK.
5. Department of Biological Sciences, Macquarie University, North Ryde, NSW 2109, Australia.
6. Centre for Population Biology, Imperial College London, Ascot SL5 7PY, UK.