Andrew H. Knoll is a professor of Natural History at Harvard University and a leading expert in the field of paleobiology. He is the author of numerous books and articles on the history of life on Earth, and his research has focused on the evolution of early life forms and the environmental conditions that shaped them. He has also served as a consultant to the National Aeronautics and Space Administration (NASA) on the search for life on other planets. Knoll has received numerous awards and honors for his work, including the National Medal of Science and the Tyler Prize for Environmental Achievement. He is a member of the National Academy of Sciences and the American Academy of Arts and Sciences.