Tuesday, August 12, 2008

Book Review: The Cell's Design: How Chemistry Reveals the Creator's Artistry


[Note: I have been asked to review this book by the American Scientific Affiliation journal Perspectives on Science and Christian Faith. This is a first draft for an eventual published review, so if you post comments they can help me refine/expand!]

The Cell's Design is both new and old at the same time. It represents a new line of argument for the Intelligent Design hypothesis, and yet the argument itself is as old as William Paley's Watchmaker Argument. Fazale Rana, vice-president at Reasons to Believe and co-author of Origins of Life with Hugh Ross, describes his strategy in the preface: "Instead of arguing for creation by relying on the perceived inability of natural processes to generate life's chemical systems, this approach frames the support for intelligent design in positive terms by highlighting biochemical features that reflect the Creator's signature." Rana uses "Biochemistry as Art" as a consistent metaphor for design throughout this book, beginning most chapters with a famous painting and inventive links to a school of art. Often "Biochemistry as Engineering" is used as a secondary metaphor, with analogies drawn to quality assurance steps in manufacturing and other similar processes.

As a practicing biochemist, I welcome this change in strategy and tone from the increasingly narrow confines of the Irreducible Complexity argument found in Michael Behe's Darwin's Black Box (referred to passingly but approvingly by Rana). The complexity of DNA Polymerase III, for example, deserves our admiration, as do other complex biochemical processes. As much as half of this book is spent explaining these biochemical workings for an audience assumed to have no prior experience with biochemistry. As instruction, it is adequate, although a book centered around the beauty of nature should itself be beautiful, while the cartoons depicting these processes are simplified and drab. Standard biochemistry textbooks convey the complexity of these machines better, although for a different audience, as does the online video “The Inner Life of the Cell.” The level at which Rana describes biochemical mechanisms seems chosen to support the underlying argument, which compares biochemical assemblies to cogs in a watch. This is most easily accomplished by depicting the proteins simply, minimizing their fluid nature. Most importantly, this depiction elides the fact that all these proteins are polymers of the same 20 amino acids, in every species, on every continent, a fact that allows for adaptation and transformation.

Often Rana’s arguments boil down to describing how molecules work and calling it “fine-tuning” -- when it very well could have been simple adaptation to available conditions. Chapters include discussions of minimal genomes, assembly of protein machines, production of proteins from DNA, gene structures and organization, membrane structures, and rebuttals to previous claims of poor design. A few strong arguments are mixed in with weaker ones. The speed of the development of the genetic code is indeed astonishing, occurring just about as soon as the Earth cooled enough to support life. The finding that DNA replication machinery may have 2 origins instead of one is also "too wonderful for me" to fully describe. But maybe it evolved twice – that is too quickly glossed over, as is the counter-argument that out of millions upon millions of organisms, we can reduce DNA polymerases to only 2 possible ancestors.

Chapter 11, on evidence for convergence of biochemical function, is a prime example of the missed opportunities in this book. Several fascinating examples of convergence are listed, but in a list that tells little more than the titles of papers that could be obtained from a perfunctory PubMed search. Stephen Jay Gould’s argument that evolution is contingent is recapped and rebutted, but the ideas of Simon Conway Morris, who has made a career out of collecting examples of convergence, are not mentioned. What could be a strong point for the book becomes little more than a laundry list.

To Rana’s credit, some alternate evolutionary explanations are described, such as in the case of the formation of the genetic code. Most times, however, possible evidences for common descent and divergent evolution are not included. The most complex examples of biochemical machinery are cherry-picked and described in detail, while similar, simpler prokaryotic versions that accomplish the same task are omitted. Much is made of the precise location of a few specific amino acids for protein function, while it is left unsaid that these crucial amino acids are only 1-2% of the total, while many others can be changed without significant loss of function. Overlapping genes are emphasized as evidence of deliberate design, while the fact that these genes are a tiny minority of cases, often at the very ends of genes in genomes under extreme pressure, is left unsaid. No mention is made of the endosymbiotic theory for formation of mitochondria, although that event would hold several possibilities for discussing artistry, theology, and the methods of a creator.

I would like to know what specific predictions are made by Rana’s model of creation, in which separate species are designed and accumulate only deleterious mutations over time. Why are bacterial and human polymerases so similar if they were created separately? Why are there no designs that are clearly impossible without a Creator, such as a species that uses 20 unique amino acids or a different genetic code? (Surely not everything must be optimized exactly the same exact way for life to exist!) What phylogenetic patterns should be deduced if mutations are only harmful, reducing proteins from an optimized starting point? What old, optimal proteins can you identify, and what stepwise progression downward is observed?

The wonder of biochemistry and what it may reveal about the Creator is indeed a worthy topic, and Rana often tells us how elegant and efficient these protein machines are. But if it is a possibility that the Creator chose to form a universe where all life sprang from a single point, and one in which chemical changes could cause life to adapt itself to the world around it over millennia, it does not substantially decrease the wonder of biochemistry, which is the main point of this book. In fact, if He chose to do so through chemistry rather than direct manipulation of atoms, that is a more elegant and efficient solution than having multiple, directly manipulated starting points. It also would give a book like this more to say if the evolutionary processes could be detailed. Such arguments would be more aesthetically satisfying and would reveal a creator more worthy of praise.

As a statement of biochemical wonder, this book is a step in the right direction. As scientific discussion, it is largely inadequate and slanted. Evidence of this can also be found by counting the promotional quotes inside the book’s cover: all are from ministers, none are from scientists. I hope other scientists will follow Rana’s lead and develop more substantial books about the wonder of biochemistry in creation, while remaining open to all possible techniques by which the Divine Artist may have created.

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