MONAD TO MAN: The Concept of Progress in Evolutionary Biology.

By Michael Ruse. Harvard University Press. 640 pp. $49.95

Evolutionary biology is seductively metaphorical. Its evidence points in so many suggestive directions that its practitioners are naturally tempted to make global speculations. Charles Darwin understood this very well, and knew moreover that it could lead to unfounded ideas as well as innovative ones. Concerned to establish his new theory as serious science, Darwin laid out a rigorous formula for evolutionary discourse, explicitly rejecting—for himself and his followers—the more speculative style of early evolutionists such as Jean Lamarck and Darwin’s own grandfather Erasmus.

Over the long term, however, such restraint was a lot to ask. Beginning with T. H. Huxley, evolutionary biologists arrived at a two-track solution to the problem: they published one set of books and articles to establish professional credentials, and a distinct but parallel set to appeal to popular audiences and to serve as an outlet for speculation. This strategy has not been lost on mainstream biologists, many of whom see evolutionary biology as a field tainted by the imposition of cultural values. They pay lip service to it but in practice regard it as a less-than-orthodox subject for research.

Rightly so, says Ruse, professor of philosophy and zoology at the University of Guelph in Ontario. He argues that evolutionary studies have been shaped from the beginning by an overarching "concept of progress" that does not, despite its secular nature, fit comfortably into the scientific enterprise. In this methodical study, he tries to show how notions of social and moral betterment—and their perceived connection to biological progression from microorganism to man—have influenced the scientific thought of major Anglo-American figures from Herbert Russell Wallace to George Gaylord Simpson and Geoffrey Parker.

The case is not always convincing. Consider Ronald A. Fisher (1890–1962), whose achievement was to add nuance and mathematical structure to evolutionism by combining Darwin’s theory of natural selection with Gregor Mendel’s principles of genetics. Fisher was passionately interested in eugenics and believed, erroneously, that almost all human abilities are innate. Ruse asserts, but does not really prove, that Fisher’s enthusiasm for human progress through breeding distorted his actual scientific work.

More compelling is Ruse’s examination of the contemporary debate over Edward O. Wilson’s theory of sociobiology, which posits that human social behavior can be understood in terms of evolutionary origins. Ruse makes the cogent point that while Wilson’s enthusiasm for cultural progress has led to an explicitly stated belief in biological progress, the same enthusiasm in Stephen Jay Gould has led to a career built on energetic denial of biological progress. In this modern context, it does seem that evolutionary biology has become infused, indeed polarized and defined, by an underlying cultural value.

—David Reich