Roger Tory Peterson had already made his mark with his innovative field guide when he conducted DDT research during World War II. By combining the tireless observation of a scientist with the imaginative skills of an artist and writer, Peterson created a field guide that Robert Bateman, in his foreword to the fifth edition, says was the doorway for millions of people into the wonderland of natural history. Peterson’s magnum opus, now in its fifth edition, created the trail for countless field guides to follow.