From the authors of Lucy: The Beginnings of Humankind (Maitland, a paleoanthropologist, discovered the famous fossil), a lucid and readable account of evolutionary theory. Beginning with such scientists as Linnaeus, who gave us a way to see relationships among species, and Hutton, whose geology questioned the biblically derived age of the earth, Edey and Johanson lead up to Darwin's world-changing insight (Wallace is not slighted). From here, the authors turn their gaze inward, explaining the mechanics of evolution on a cellular/molecular level. With the egregious exception of casting Mendel's work in terms of mixing chicken and ham pate, they've done remarkably well in rendering this complex material straightforward and accessible. Furthermore, their account of pioneering work--such as T.H. Morgan's in the Fly Room, and Watson and Crick's at Cambridge--conveys the excitement of doing ground-breaking science. Having brought us up to date on the mechanics of DNA and RNA, the authors then offer a few insights into current work: theories of origin, including clay lattices; the beginnings of molecular anthropology in Sarich's work with blood proteins; and the revised family trees to which the new science has led. They close with a cautionary afterword. Despite some condescending authorial intrusion ("'Hold it,' said Don. 'Hold it right there. These explanations are tricky. Are you sure our readers are going to understand the principles underlying this stuff?'"): an enjoyable, painless, introduction to--or refresher in--a fascinating field.