John D. Reynolds is a Reader in Evolutionary Ecology at the University of East Anglia, Norwich, UK. Georgina M. Mace is the Director of Science at the Institute of Zoology, Zoological Society of London, UK. Kent H. Redford is Director of Biodiversity Analysis at the Wildlife Conservation Society, New York, USA. John G. Robinson is Senior Vice-President and Director of International Conservation at the Wildlife Conservation Society, New York, USA.