This page contains the text of a review of The Pursuit of Perfection by E. Hatton published in The Biochemist (2004)
Evolution has long been popular reading material for scientists and non-scientists alike, and in this book Athel Cornish-Bowden attempts to bring complicated ideas relating biochemistry to evolution to a wide audience.
The reader is reminded of basic biochemistry principles, with good explanations of the mechanisms of evolution and the fixation of genes in a population. We consider the Panglossian view, taken from Voltaire’s Candide, which suggests adaptation to some optimal goal has caused organisms and processes to behave the way they do. That is, there is a purpose for everything, and evolution proceeds because improvements are constantly made. What then, the author asks, is the reason for the junk DNA that makes up so much of the human genetic code? Perhaps it is simply that we do not yet understand its function, but is it likely that a lungfish contains 20 times as much DNA as a human because it is 20 times more complex?
The work of Meléndez-Hevia has clearly inspired much of this book, with several chapters dedicated to the idea of the evolution of metabolism to an optimum. Using metabolic pathways, we learn that in certain examples, cells appear to have come to the best possible solution. By comparison to simple logic puzzles, the pentose phosphate pathway is analysed in terms of the total number of possible steps. This simple analogy is extended to glycolysis, and the Calvin Cycle in photosynthesis. The selective advantage to an organism that utilises a simple metabolic pathway over a more complicated one is made clear to us with the inventive comparison to experiments that we could easily carry out at home
This is Cornish-Bowden’s achievement; to bring complicated biochemistry down to everyday phenomena, making the book highly readable and accessible to students.
We learn that the cell has reached the optimum level of efficiency for these metabolic pathways, but this is tempered with a reminder that not all of metabolism may yield the same result when analysed and that more research is needed before drawing firm conclusions.
Of course, if metabolic pathways are optimised for efficiency, then why not individual molecules? Glycogen is the example given, and the branching, layered structure is assessed mathematically, providing a convincing argument that this storage molecule, whether in the liver or muscle, is indeed designed in the best way possible.
Biology never provides perfect results, as we are reminded in a chapter highlighting the danger of misinterpretation of data. It is useful to bring the theory back to practical results, and the cautionary note is perhaps one of which every scientist needs reminding.
Biochemistry is clearly an invaluable tool with which to study natural selection and evolution. After a lengthy discussion of enzyme kinetics, the final chapter focuses on the evolution of cancer, related to metabolic regulation and mutation. It would have been interesting to include here other topical aspects of evolution in terms of biochemistry, such as drug resistance and genetic modification.
It is refreshing to see evolution from a biochemical aspect presented in such an accessible way. Although this book is not for a newcomer to biochemistry, the ideas are clearly explained. Light reading for a biochemist, but within reach of the undergraduate, this is an engaging introduction to a vast subject.