Dawkins: The Greatest Show on Earth

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Dawkins: The Greatest Show on Earth – The Evidence for Evolution?
Richard Dawkins', The Greatest Show on Earth, hopes to convey and document some of the evidence which compels him to embrace a Darwinian perspective on origins. Dawkins is also author of The God Delusion and probably today’s best known Darwinian apologist. Dawkins, in his new book lives up to his legendary reputation of creative tale-telling.

Just how strong are Richard Dawkins’ arguments? Does he present anything new? Do his claims stand up when subjected to careful scrutiny? Richard Dawkins clearly thinks so. In chapter 1 of his book, entitled Only a theory? Dawkins remarks:

    Evolution is a fact. Beyond reasonable doubt, beyond serious doubt, beyond sane, informed, intelligent doubt, beyond doubt evolution is a fact. The evidence for evolution is at least as strong as the evidence for the Holocaust, even allowing for eye witnesses to the Holocaust. It is the plain truth that we are cousins of chimpanzees, somewhat more distant cousins of monkeys, more distant cousins still of aardvarks and manatees, yet more distant cousins of bananas and turnips…continue the list as long as desired. That didn’t have to be true. It is not self-evidently, tautologically, obviously true, and there was a time when most people, even educated people, thought it wasn’t. It didn’t have to be true, but it is. We know this because a rising flood of evidence supports it. Evolution is a fact, and this book will demonstrate it. No reputable scientist disputes it, and no unbiased reader will close the book doubting it.
One wonders, of course, how many times Richard Dawkins believes that he has to rephrase the core contention of his book in order to legitimise it!

Richard Dawkins further remarks:
    …Imagine you are a teacher of recent history, and your lessons on 20th century Europe are boycotted…by politically muscular groups of Holocaust deniers. The plight of many science teachers today is not less dire. When they attempt to expound the central principle of biology they are harried and stymied, hassled and bullied.
Such dogmatic rhetoric and ad-hominen name-calling is highly indicative of the level of Dawkins’ argumentation. Nonetheless, it should be noted that no critic of Darwinism seeks the outlawing of the concept of evolution -- or even common descent -- from the academic environment. Rather, most critics would argue that the significant criticisms of Darwinism -- which are, as yet, without resolution -- should be referenced such that Darwinism is not taught in an uncritical fashion. Richard Dawkins’ claim, then, that critics want to torpedo the public education system is a simple point of misrepresentation.

Dawkins: The Greatest Show on Earth – The Origin of Life
Richard Dawkins, in The Greatest Show on Earth, has very little to say concerning the most fundamental challenge to standard materialistic thinking, namely the problem of life’s origin. In chapter 13 of his book, Dawkins writes:

    We have no evidence about what the first step in making life was, but we do know the kind of step it must have been. It must have been whatever it took to get natural selection started. Before that first step, the sorts of improvement that only natural selection can achieve were impossible. And that means the key step was the rising, by some process as yet unknown, of a self-replicating entity.
Dawkins is overlooking or ignoring a host of key points here. As Dawkins himself concedes, natural selection can only occur in organisms which are capable of reproducing or replicating themselves. But surely any self-replicating mechanism must exhibit a definable minimal level of complexity, let alone the necessitude of functional, and thus sequence specific DNA and protein molecules. As theoretical biologist Howard Pattee explains in his The Problem of Biological Hierarchy: “There is no evidence that hereditary evolution occurs except in cells which already have…the DNA, the replicating and translating enzymes, and all the control systems and structures necessary to reproduce themselves.” In order to invoke a materialistic pathway which can account for the origin of specified information in DNA, the naturalist must invoke a process that itself depends upon pre-existing sequence specific DNA molecules. Yet, the origin of these molecules is precisely what the thesis seeks to explain. And let us not forget that it is not merely the sequence of base-pairs comprising the information in DNA which is the chief concern at this point -- but the problem becomes even deeper when confronted with the paradox of the origin of the genetic code itself.

Dawkins: The Greatest Show on Earth – RNA world
Dawkins, The Greatest Show on Earth, proceeds to outline the classic Catch-22 paradox which concerns the relationship of DNA to proteins. He writes:

    The ‘Catch-22’ of the origin of life is this. DNA can replicate, but it needs enzymes in order to catalyse the process. Proteins can catalyse DNA formation, but they need DNA to specify the correct sequence of amino acids. How could the molecules of the Early Earth break out of this bind and allow natural selection to get started?
How does Dawkins attempt to resolve this enigma? He continues:
    Now for the key point of the ‘RNA World theory’ of the origin of life. In addition to stretching out in a form suitable for passing on sequence information, RNA is also capable of self-assembling…into three-dimensional shapes which have enzymatic activity. RNA enzymes do exist. They are not as efficient as protein enzymes, but they do work. The RNA World theory suggests that RNA was good enough enzyme to hold the fort until proteins evolved to take over the enzyme role, and that RNA was also a good enough replicator to muddle along in that role until DNA evolved.
Curiously, Richard Dawkins spends no time in The Greatest Show on Earth attempting to address the numerous criticisms of the RNA-first model. For example, the formation of the first RNA molecule would have necessitated the prior emergence of smaller constituent molecules, including ribose sugar, phosphate molecules and the four RNA nucleotide bases. But both synthesising and maintaining these essential RNA molecules (particularly ribose) and the nucleotide bases is profoundly problematic, if not impossible to perform under realistic prebiotic conditions.

Further, naturally occurring RNA molecules possess very few of the specific enzymatic properties of proteins. Ribozymes can perform a small handful of the thousands of functions performed by proteins. The inability of RNA molecules to perform many of the functions of protein enzymes raises a third and related concern with regard to the tenability of the RNA-first model. To date, no plausible explanation has been advanced as to how primitive self-replicating RNA molecules could have made the transition into modern cellular systems which depend heavily on a variety of proteins to process genetic information. Consider the transition from a primitive replicator to a system for building the first proteins. Even if such a system of ribozymes for building proteins had arisen from an RNA replicator, that system of molecules would still require information-rich templates for building specific proteins. To date, there is no materialistic pathway by which specified information can be readily produced.

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