Gerald N. Callahan, Ph.D., is a professor of immunology at Colorado State University. He has more than thirty years of experience in modern biomedical research. His science articles have appeared in "Nature," "Journal of Experimental Medicine," and "Journal of Immunology," Callahan is also a poet and essayist, and his writings have been published by "Creative Nonfiction," "Southern Poetry Review," and "Cream City Review,"