Signature in the Cell: DNA and the Evidence for Intelligent Design is not what I had original thought it would be. The title suggested that it was a book about the evidence for intelligent design through the molecular machines found in the cell. Since I had read Fuz Rana's excellent book The Cell's Design: How Chemistry Reveals the Creator's Artistry, I figured I didn't need another book on cell design. However, Signature in the Cell is really about the origin of life and how all the current data points to a non-naturalistic origin of life. In the book, author Stephen Meyer takes us through the history of origin of life research, beginning with the discovery of the structure of DNA in the 1950s.
History of origin of life research
Meyer begins with the history of the discovery of DNA's structure by Watson and Crick (among others). The story is a fascinating description of how the two young researchers determined DNA's structure mostly through using clues derived from the research of others. Watson and Crick thought "outside the box" to solve the puzzle that opened up the secrets of how living organisms operate. Much of the initial chapters of the book describe Meyer's own personal discovery of why intelligent design provides a better explanation of life's beginnings than any naturalistic model. Meyer originally earned degrees in physics and geology and began working for an oil company in Texas looking for oil deposits. Meyer's interest in DNA and design led him to apply for a scholarship and enrolled to study the history and philosophy of science at the University of Cambridge. After completing his Ph.D., Meyers became involved in the intelligent design movement, producing numerous papers and books.
Much of the emphasis of Signature in the Cell is on information theory. We all know that DNA contains the information necessary to build and run living organisms. During the development of computing systems, mathematician, Claude Shannon developed "The Mathematical Theory of Communications." Information theory relates the probability of a specific sequence of information in a sequence of bits. Depending upon length, any random sequence of information has a certain probability based upon its length. However, this random "Shannon information" is not the basis of the claim that DNA has been designed by an intelligent being. In order to provide evidence for intelligent design, the information must be both improbable and specified. One of the best examples of specified information comes from the search for a hypothetical first RNA replicator. In order to find just one partial replicator, scientists had to go through a list of 1015 different RNA molecules. The fact that RNA replicator sequences are rare, coupled with specificity requirement makes the appearance of the first replicator extremely unlikely.
The basis of the intelligent design claim is that it provides more explanatory power than competing theories about the origin of information and the origin of life. Although origin of life researchers had attempted to explain the appearance of the first replicator through some kind of law of physics or chemistry, it became apparent as more research was done that no such law existed. Therefore, all origin of life theories must rely upon chance as the designer of the information required to form the first organism. With limited time and the limited size of the universe, the laws of physics do not provide a reasonable explanation as to how the required information arose through random process. In contrast, intelligent beings are capable of and have the motivation to produce information-rich designs. So, the intelligent design theory provides superior explanatory power regarding how the first living organism arose.
Origin of life theories
Meyers gives an excellent review of the numerous naturalistic origin of life theories that have been proposed over the years and why those theories have failed (nearly all have been rejected by contemporary origin of life researchers. Today, there are two main origin of life theories—both of which have serious theoretical and practical deficits. Metabolism-first theories suffer from the requirement to produce numerous energy-harvesting enzymes within some kind of membrane barrier in the absence of any specific way to replicate such a system. Meyers shows that the probability of getting just one such enzyme is impossible, given the age and size of the universe. The most "promising" origin of life theory is the RNA World. However, as mentioned previously, attempts to find even a partial RNA replicator have proven extremely difficult, even with intelligent beings designing such replicators. The main problem with the replicator hypothesis is that not just one sequence needs to form by chance, but that sequence and its exact complementary strand. Gerald Joyce and Leslie Orgel calculated that in order to get just one 50-mer replicator would require an RNA library of 1048 molecules—which exceeds the mass of the earth! Even more concerning is that the minimum replicator size found to-date is 189-mer, which is much less likely to be produced compared to a 50-mer. Even the 189-mer replicator can only replicate 10% of its sequence under ideal conditions. Obviously, for any replicator to work, it must be capable of replicating 100% of its sequence. Although really informative, this section of the book is necessarily somewhat technical, so a non-scientist will find the material challenging. As a scientist, I found the information really helpful.
Is ID science?
Meyers spends the final few chapters on the question of whether intelligent design qualifies as science. Much of the discussion centers around definitions of science among the different scientific disciplines and how those definitions apply to intelligent design theory. Meyers shows that not all disciplines of science fit neatly in the standard definitions of what science is. In other words, things such as testability and falsifiability are difficult to apply to historical sciences, such as evolution. Likewise, these characteristics are generally not applicable to intelligent design. To a certain degree, I tend to agree with scientists who complain that intelligent design is difficult to test or falsify. Likewise, intelligent design cannot produce a model, because it has no basis on which one can be created. In contrast, something like biblical creationism, which is based upon statements from the Bible, can produce a model that can be tested by future scientific discoveries.
Signature in the Cell by Stephen Meyer is a really good examination of the issues surrounding origin of life research and how intelligent design theory can contribute to the discussion. The book is relatively long at 624 pages, but about 30% of that is devoted to notes and appendices. I particularly like that the book is well-referenced and will be looking into many of the issues more thoroughly when I get a chance. Most of the book is quite readable, even for somebody without an extensive science background. In addition, there are a fair number of philosophical arguments that are cited, which would be more appealing to general, non-science audiences. In my opinion, origin of life research provides probably the best evidence for intelligent design theory and Meyers does a really good job explaining it. So, I highly recommend Signature in the Cell if that is where your interests lie.
Signature in the Cell: DNA and the Evidence for Intelligent Design (Paperback)
by Stephen C. Meyer
Date published: June 22, 2010
- Book Review: Darwin's Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design
- Book Review: Science and Human Origins
- Book Review: The Cell's Design: How Chemistry Reveals the Creator's Artistry
Last Modified June 27, 2013