1. Trophic Cascades Program, Department of Forest Ecosystems and Society, Oregon State University, Corvallis, OR 97331, USA.
2. Desert Ecology Research Group, School of Biological Sciences, The University of Sydney, Sydney, New South Wales 2006, Australia.
3. Department of Biology, Stanford University, Stanford, CA 94305, USA.
4. Centre for African Conservation Ecology, Department of Zoology, Nelson Mandela Metropolitan University, Port Elizabeth 6031, South Africa.
5. Departamento de Ecologia, Universidade Estadual Paulista (UNESP), C.P. 199, Rio Claro, São Paulo 13506-900, Brazil.
6. College of Natural Sciences, Bangor University, Thoday Building, Deiniol Road, Bangor, Gwynedd LL572UW, UK.
7. Department of Fisheries and Wildlife, Oregon State University, Corvallis, OR 97331, USA.
8. Lion Program, Panthera, 8 West 40th Street, 18th Floor, New York, NY 10018, USA.
9. Mammal Research Institute, Department of Zoology and Entomology, University of Pretoria, Pretoria, Gauteng 0001, South Africa.
10. Wildlife Conservation Research Unit, Department of Zoology, University of Oxford, Recanati-Kaplan Centre, Tubney House, Tubney, Abingdon OX13 5QL, UK.
11. Environmental Change Institute, School of Geography and the Environment, University of Oxford, Oxford OX1 3QY, UK.
12. Nicholas School of the Environment and Earth Sciences, Duke University, P. O. Box 90381, Durham, NC 27708, USA.
13. Department of Ecology and Evolutionary Biology, University of California, Los Angeles, Los Angeles, CA 90095–7239, USA.