1. Discipline of Zoology, School of Natural Sciences, Trinity College Dublin, Dublin 2, Ireland
2. Department of Anatomy and Physiology, and Centre for Veterinary Wildlife Research, Faculty of Veterinary Science, University of Pretoria, Pretoria, Gauteng 0110, South Africa
3. Institute of Zoology, Zoological Society of London, Regent's Park, London NW1 4RY, UK
4. School of Veterinary Science, University College Dublin, Belfield, Dublin 4, Ireland
5. Department of Paleontology, University of Zurich, Zurich, Switzerland
6. Department of Biosciences, Swansea University, Swansea, UK
7. Smithsonian Tropical Research Institute, Balboa, Panama