1. Université de Lyon; F-69000 Lyon France
2. CNRS, UMR5558; Laboratoire de Biométrie et Biologie Evolutive; Université Lyon 1; F-69622 Villeurbanne France
3. Muséum national d'Histoire naturelle; Département Ecologie et Gestion de la Biodiversité; UMR 7204-CNRS-UPMC; CP 51, 55-61 rue Buffon 75005 Paris France
4. Mathematical Ecology Research Group; Department of Zoology; University of Oxford; South Parks Road OX1 3PS Oxford UK
5. Department of Virology and Microbiology; Centro de Biología Molecular Severo Ochoa CSIC/UAM; 28049 Madrid Spain