According to Jared Diamond, “evolution is the most profound and powerful idea to have been conceived in the last two centuries.” Almost all biologists no longer consider evolution “just a theory;” rather, it’s a fact. The textbooks say that evolution is the selection and preservation of favorable mutations across generations. Genes mix and match, and the more successful at surviving — survive and pass on the winning genes to their offspring. But how does innovation occur? How do new life forms arise from old ones? This is the mystery discussed on this show with Andreas Wagner, the author of the new and original book, Arrival of the Fittest: Solving Evolution’s Greatest Puzzle.