In a prodigious feat of scholarship, historian-of-science Bowler (Queens U., Belfast) restores Darwin's rightful luster in the face of countless attacks from right, left, and center. (Viz., for specialists, Bowler's 1983 Eclipse of Darwinism.) The history of the idea of evolution, in his view, cannot be divorced from the cultural context of the thinker. Thus, the atheistic, materialist-minded Enlightenment philosophes, often considered forerunners of evolutionism, constructed closed rather than openended systems. Though Buffon, Diderot, and others struggled with the change in life forms (and sometimes introduced spontaneous generation to explain life's origins), they essentially fashioned a predictable universe unfolding in a predetermined pattern. Some naturalists tried to reconcile Christianity with change by amending the Great Chain of Being: adding branches or postulating more complex relationships. The century ended with Cuvier, defender of the fixity of species. Nonetheless, it was Cuvier's comparative anatomy and systematization of basic body types that helped set the stage for the Darwinian innovations. Utilitarianism and laissez-faire economics, in turn, colored Darwin's world view. So did German idealism--which, translated into biology, became a historical unfolding toward a predetermined goal. Bowler's portrait of Darwin is the book's centerpiece. Account is taken of the influence of British geologists and botanists; of Darwin's habit of populational (rather than typological) thinking; of his sophisticated scientific methods (as against mere observation). Bowler also traces reactions to Darwinism--early acceptance, turn-of-the-century rejection, the rise of alternative theories (neo-Lamarckism, othogenesis, Mendelianism). The book's concluding sections deal with 20th-century developments: the currents that led to the reconciliation of gene theory, population genetics, and natural selection in what has been called (by Ernst Mayr and others) the modern synthesis. Finally, Bowler discusses current modifications of Darwinism from within--theories of punctuated equilibria and cladistics, as well as attacks from the pseudoscientific and creationist fringe. In the preface, Bowler speaks of his wish to reach lay readers; his prose exemplifies a passion for clarity and straightforward explanation.