1. Center for Regenerative and Developmental Biology and Department of Biology (L.N.V.), Tufts University, Medford, Massachusetts 02155;
2. The Endocrine Disruption Exchange (T.C.), Paonia, Colorado 81428;
3. Laboratory for Integrative Studies in Amphibian Biology (T.B.H.), Molecular Toxicology, Group in Endocrinology, Energy and Resources Group, Museum of Vertebrate Zoology, and Department of Integrative Biology, University of California, Berkeley, California 94720;
4. Division of Extramural Research and Training (J.J.H.), National Institute of Environmental Health Sciences, National Institutes of Health, U.S. Department of Health and Human Services, Research Triangle Park, North Carolina 27709;
5. Division of Epidemiology and Community Health (D.R.J.), School of Public Health, University of Minnesota, Minneapolis, Minnesota 55455;
6. Department of Preventive Medicine (D.-H.L.), School of Medicine, Kyungpook National University, Daegu 702-701, Korea;
7. Molecular Profiling Laboratory (T.S.), Massachusetts General Hospital Center for Cancer Research, Charlestown, Massachusetts 02129;
8. Department of Anatomy and Cellular Biology (A.M.S.), Tufts University School of Medicine, Boston, Massachusetts 02111;
9. Division of Biological Sciences (F.S.v.S.) University of Missouri-Columbia, Columbia, Missouri 65211;
10. Department of Biomedical Sciences (W.V.W.), University of Missouri-Columbia, Columbia, Missouri 65211;
11. Biology Department (T.Z.), University of Massachusetts-Amherst, Amherst, Massachusetts 01003
12. Environmental Health Sciences (J.P.M.), Charlottesville, Virginia 22902