After a brief review of his own personal intellectual journey vis-a-vis Darwinism, Behe begins Darwin Devolves by discussing the problems facing any theory that purports to account for life. This discussion is followed by a description of some amazingly complex biological systems that, according to Behe, "demand explanation." Behe next examines the various theories that have been proposed to explain the features of life while evoking purely naturalistic mechanisms, starting from Darwin's original theory of evolution to more recent non-Darwinian explanations. Behe contends that each of these theories has limited explanatory power. Behe then discusses a number of recent studies pertaining to the evolution of various species. These studies, he argues, demonstrate that Darwinian-style evolution is, in fact, self-limiting, being only able to create new species and genera--the two lowest levels of biological classification. Moreover, contrary to what has generally been thought, the Darwinian process of natural selection seems to act primarily on genes that have been degraded or broken (hence "Darwin devolves"), rather than on genes that have developed some new, beneficial function.
Behe ends Darwin Devolves by arguing that only the existence of mind can explain life on earth. Only a mind, acting with purpose, would have been capable of assembling complex biological systems, including those at the molecular level. The question, of course, is whose mind? Since Behe is a theist--specifically, a Roman Catholic--he has no trouble with the idea that the mind in question is the mind of God. However, ID theory is potentially consistent with nontheistic world views. For example, the mind in question could be that of some super-advanced alien race, or perhaps mind is an inherent characteristic of the universe.
Needless to say, the views Behe expresses in this book--and ID theory in general--are highly controversial. Many biologists are dismissive of ID, describing it as "creationism in a cheap tuxedo." Thus, perhaps it is not surprising that I found Behe's book in the religion section of my local Barnes & Noble bookstore, rather than in the science section. Nonetheless, I personally found Behe's arguments in Darwin Devolves to be quite convincing. Moreover, Behe generally writes in a manner that makes fairly complex scientific concepts relatively easy to understand for a non-scientist like myself. Consequently, I highly recommend Darwin Devolves to anyone who has an interest in the debate over Darwinism.
Image of Michael J. Behe from discovery.org