The black box set ticking

A black box is a term for a device that performs some task, but whose inner workings remain mysterious to the operator. Charles Darwin formulated the theory of evolution through his detailed observations of nature but without any information about the working of a cell or of its biochemistry. The author of this book comes to the conclusion that had more recent biochemical research data been available about the inner workings of the cell, when Darwin's theory was proposed, then there would not have been such a schism between science and belief in a supernatural power or an intelligent designer.

This is not a book by a literal creationist who believes that the world was created only 10,000 years ago, nor is it a refutation of the process of change gradually through evolution by natural selection. The concern of the author is the origin of life and the biological complexity needed for it to arise rather than for the details of developments from the basic complexity which can be explained in Darwinian terms. It is the author's thesis that in life there are many irreducibly complex biochemical systems that could not have been formed in a gradualistic manner. After two most readable introductory chapters, in the second part of the book, the author has chosen five systems to illustrate his thesis. Each is described in considerable detail and will be helpful to biologists and non-biologists alike.

In several places there are apologies for the biochemical details needed to present the case, but the more technical descriptions are marked so that the non-specialist reader can skip them if so desired. Even the technical parts are in fact considerably condensed and simplified accounts of the actual processes, and only basic biochemical knowledge is needed to understand them.

The five main biochemical and cellular processes described are the cilium and the bacterial flagellum, the process of blood clotting, the transport of materials and energy in cells, self-defence in cells and, less convincingly, the construction of the big polymer molecules that do the work in a cell, proteins and nucleic acids. Throughout the book we are introduced to physical machines such as a mousetrap or one of cartoonist Rube Goldberg's creations and shown how one part could not function without the other and that each part could not have a function related to the other through a gradual process. The author maintains that the systems he describes have several different components that could not have been combined gradually through the process of evolution. The rotary motor of a bacterial flagellum or the amazing combination of proteins that clot blood at the correct time but let it flow freely normally provoke in the author the same fascination and curiosity that the processes of the whole organism gave to Darwin over 100 years ago. However, their conclusions are different and Michael Behe concludes that the systems he studies are too complicated to have evolved and must have had an intelligent designer to start them off.

There are many attempts to knock down Richard Dawkins, who is accused of over simplification in order to convince his readers and who has come to the opposite conclusion as a result of his studies of evolution. Certainly the examples and the metaphors used by Dawkins flow much more readily and at times those of Behe do not help to clarify his argument. However, on the whole the latter has chosen a topic which is far harder to explain in simple terms than many of the examples cited by Dawkins.

There appears to be an unfortunate dichotomy between evolutionary biology and biochemistry and Behe shows, through an analysis of papers published in biochemical journals, how little mention is made of evolution in the biochemical literature. There is obviously a need for much more cross-fertilisation between these disciplines and as a biologist I found myself sympathising with Dawkins in several places.

Behe provides an interesting analysis of William Paley's Natural Theology that inspired the title of Dawkins's book, The Blind Watchmaker. He concludes that although Paley was, in most cases, describing what were to him biological black boxes, in contrast his example of a watch was not a black box because its components and roles were known. The author contends that the main argument of the long discredited Paley has now actually been refuted: "Paley's biological examples are a mixed bag, ranging from the truly astonishing to the mildly interesting to the rather silly, from mechanical systems to instincts to mere shapes". However, the black boxes that really reveal an intelligent designer are to be found at the molecular and cellular level rather than the organismic level.

The third part of this book is an excellent and non-technical discussion of the implications of the complexity of the systems in the black boxes discussed. It is of necessity somewhat controversial since science has not yet discovered an intelligent designer of these complex biological systems. Will the answer be found from science or from the discovery of an intelligent creator of life?

Is this book really about Darwin's black box, the contents of which have been revealed by the biochemists and molecular biologists who have succeeded him, or are we faced with another black box, Behe's black box that has still to be explained? I for one welcome a book that acknowledges the necessity of an intelligent designer to explain the origin and the wonder of life on our planet.

Sir Ghillean Prance is director, Royal Botanic Gardens, Kew.