George Johnson, Ph.D.
Dr. George Johnson is a professor of biology at Washington
University in St. Louis, where he has taught general biology and
genetics to undergraduates for 30 years. Dr. Johnson is also a
professor of genetics at Washington University School of
Medicine. He is the author of more than 50 scientific publica-
tions and has published several successful college biology texts.
Peter Raven, Ph.D.
Dr. Peter Raven is the director of the Missouri Botanical Garden
and a professor of botany at Washington University in St. Louis.
Dr. Raven is a MacArthur Fellow, a member of the National Academy
of Sciences, a recipient of the National Medal of Science, and the
author of 20 other books and several hundred scientific articles.
ii Acknowledgments
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