1. Department of Genetics, University of Georgia, Athens, GA 30602–7223, USA
2. Department of Ecology and Evolutionary Biology, Box G‐W, Brown University, Providence, Rhode Island 02912, USA
3. Department of Ecology, Evolution & Behaviour, University of Minnesota, 1987 Upper Buford Circle, St. Paul, MN 55108–6097, USA
4. Department of Entomology, University of California, Davis, CA 95616, USA