William D. Stansfield has degrees in Agriculture (B.S., 1952), Education (M.A., 1960), and Genetics (M.S., 1962; Ph.D., 1963; University of California at Davis). His published research is in immunogenetics, twinning, and mouse genetics. From 1957 to 1959 he was an instructor in high school vocational in agriculture. He was a faculty member of the Biological Sciences Department of California Polytechnic State University from 1963 to 1992 and is now Emeritus Professor. He has written university-level textbooks in evolution and serology/immunology, and has coauthored a dictionary of genetics. Raul J. Cano is a Professor of Microbiology in the Biological Sciences Department at California Polytechnic State University. He earned his B.S. in Biology in 1970 and his M.S. in Biology in 1972 from Eastern Washington University, and his Ph.D. in Microbiology from the University of Montana-Missoula in 1974. Jaime S. Colome obtained his Ph.D. from the University of California at Santa Barbara. He has taught microbiology, genetics, cell physiology, and molecular biology at California Polytechnic State University for the last 23 years. Presently, he is researching the molecular biology of viroids and the hepatitis D virus.