Charles Darwin proposed 150 years ago that living things have descended with modification from common ancestors by the process of Natural Selection. This is the key to understanding virtually every area in biology from biochemistry, to cell biology, to organismic biology, to population biology, to ecology. Evolution is the glue that holds biology together as a coherent science, making, in the words of a famous scientist, a "meaningful picture as a whole." Nonetheless, the teaching of evolution is a contentious issue in the United States today for reasons that touch upon religion, science, history, and – inevitably – politics. Dr. Eugenie C. Scott, authority on evolution and the creationism/evolution controversy, will help to clear the air about this publicly controversial, if not scientifically controversial, topic of evolution.