Dear SS &TM:
With your big brains, think about this catch 22 paradox of the origin of life
God bless you and yours,
BH
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.
...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 infor-
mation can be readily produced.
...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. - See more at:
http://www.allaboutscience.org/dawkins-the-greatest-show-on-earth.htm#sthash.PUBhryaK.dpuf
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