1. Department of Integrative Biology University of California, Berkeley Berkeley California 94720
2. Current Address: Department of Ecology and Evolution University of Chicago Chicago Illinois 60637
3. Department of Entomology University of California, Riverside Riverside California 92521
4. Molecular and Cellular Biology Graduate Program University of Washington Seattle Washington 98195
5. Division of Basic Sciences Fred Hutchinson Cancer Research Center Seattle Washington 98109
6. School of Biological Sciences University of Utah Salt Lake City Utah 84112