1. Institut de Biologie de l´École Normale Supérieure (IBENS), Institut National de la Santé et de la Recherche Médicale U1024, Centre Nationnal de la Recherche Scientifique Unité Mixte de Recherche 8197, Paris Sciences et Lettres Research University, 75005 Paris, France
2. Department of Biology, Portland State University, Oregon 97201
3. Institute of Ecology and Evolution, 5289 University of Oregon, Eugene, Oregon 97403, and
4. Department of Biology, and
5. University of Florida Genetics Institute, University of Florida, Gainesville, Florida 32611