1. Department of Biology University of Kentucky Lexington KY 40506 USA
2. Duke Lemur Center Durham NC 27705 USA
3. Département de Biologie Animale Université d'Antananarivo BP 906 Antananarivo (101) Madagascar
4. Behavioral Ecology and Sociobiology Unit German Primate Center (DPZ) 37077 Göttingen Germany
5. Center for Health and Community University of California San Francisco CA 94118 USA
6. Department of Biology Duke University Durham NC 27708 USA