Friday, December 25, 2015

Does Neo-Darwinian Evolutionary Theory Adequately Explain Life?

Abstract

        An overview of the current state of scientific evidence that supports or undermines the theory of neo-Darwinian macro-evolution.  This is the component of evolution that defines how life originated (abiogenesis) and then developed from a universal common ancestor (single cell) to all the phyla and kingdoms presently and in the past fossil record, including the introduction of body plans, organs, tissues, epigenetic structures and the emergence of life on very limited time scales.

The Measurement Criteria   

         Two defining principles of Darwinian evolutionary theory are universal common ancestry and randomly arising, heritable variations that filtered through a competition for survival. These variations are purposeless and undirected, and must eventually prove to be of benefit to future generations of organisms for natural selection to be operative.[1] The criteria for accepting neo-Darwinian evolution as a 'scientific fact,' or even as a viable scientific theory, would be its explanatory power to show how life emerged and then passed on macro-evolutionary changes, such as new organs, tissues and body types, to future progeny. In addition, the fossil record should confirm the principle of a 'universal common ancestor' and the multitude of transitional forms over millions of years. "The fundamental problem confronting neo-Darwinism, as with chemical evolutionary theory, is the problem of the origin of new biological information. 

        Though neo-Darwinists often dismiss the problem of the origin of life as an isolated anomaly, leading theoreticians acknowledge that neo-Darwinism has also failed to explain the source of novel variation without which natural selection can do nothing…." [2] This paper evaluates the current evidence matches up against the criteria for accepting or rejecting the neo-Darwinian evolutionary hypothesis.

Starting With the Universal Common Ancestor

          How does natural selection account for the origin of life? And how did our "universal common ancestor" acquire genetic information and the ability to transmit that information across countless future generations of organisms? Evolutionary models that use natural selection as mechanism for variation presuppose self-replicating cells. Yet these cells depend upon information rich proteins and nucleic acids (DNA and RNA) in order to replicate.  Current origin-of-life research to date has failed to reveal any plausible source for this genetic information through natural chemical processes. "Theodosius Dobzhansky, one of the founders of the modern neo-Darwinian synthesis can state flatly, 'Pre-biological natural selection is a contradiction in terms.' Or, as Nobel Prize-winning molecular biologist and origin-of-life researcher Christian de Duve explains, theories of pre-biotic natural selection fail because they 'need information which implies they have to presuppose what is to be explained in the first place.'"[3]

          Dean Kenyon, in his book Biological Predestination, observed that the "...key flaw in origin-of-life research, was that the experiments were intelligent ─ unlike anything found on the primitive Earth."[4] Kenyon elaborated further in his 1995 essay, Re-creating the RNA World, that  "…In vitro RNA selection does not demonstrate that complex ribozymes could have arisen naturally in prebiotic soup, because the in vitro experimental conditions are wholly unrealistic."  Everything science knew about RNA was summed up in two rules: "According to those rules, RNA does not arise from its chemical constituents except (a) in organisms and (b) in laboratories where intelligent organisms synthesize it."[5]  

          Thus, the primary principle of a universal common ancestor is never explained by evolutionary theory.  The starting point for explaining how natural selection works is a fully functioning biological entity whose origin is simply asserted as an article of faith in Darwinian evolutionary doctrine.

Explaining the Mutation Gap

            Given a universal common ancestor, neo-Darwinian evolutionary theory must then show at least a plausible path to the chromosomal structures that we see in today in living organisms. Yet the gap between genes, when traced back to a hypothetical common ancestor, requires mutational forces that are not observable at work today in any feasible way.[6] Even for the smallest unit of functional variation, a multi-step mutative process is required with intermediate steps that nearly always render the gene inoperable. Further, most functional protein changes require simultaneous, cooperative transformation of features, usually somewhere else on the gene, in order to allow the organism to survive the original mutational change. Yet no mutational mechanism has been theorized to overcome the statistically daunting combinatorial search problem of finding just the right mutation to generate something useful to the organism that can be passed to successive generations.[7]

            Aside from having to first assume a working gene to explain mutational variation for natural selection to operate upon, but these mutations must follow a certain path originating from a common ancestor organism. "Yet genomic studies are now turning up hundreds of thousands of genes in many diverse organisms that exhibit no significant similarity in sequence to any other known gene. These "taxonomically restricted genes" or "ORFans" (for open reading frames of unknown origin") now dot the phylogenetic landscape."[8]     

            The complexity of these genetic data storehouses cannot be overstated. "The greatest known density of information is that in the DNA of living cells."[9] The information content of one nucleotide is two bits, giving a total of 12x109 bits for one DNA molecule. Divide this by the number of bits in one KB (1024); this results in a degree of integration of 11.72 million KB, which is 180 times as much as… [a 64MB microprocessor]."[10]  Modern neo-Darwinist theory has no explanation for how organisms achieved the efficiency, complexity and "technology" we see in cellular activity and replication and has no counter argument to the statistical improbability measured in achieving even the smallest functional protein fold through "natural" processes.

Protein Folds and New Functionality

            For macroevolutionary types of changes needed to generate new phyla and body plans, gene mutations - even coordinated simultaneous mutations in different parts of the gene - have been proven to be insufficient to produce new protein functions. The functionality of protein sequences is dependent upon pre-specified folds in the protein itself. In an attempt to explain genetic diversity, scientists have to first assume a working gene to splice, fuse or reposition in order to generate a new heritable genetic trait. All the mutative mechanisms proposed by scientists to date (such as exon shuffling, gene duplication, retro positioning of messenger RNA, lateral gene transfer, gene fission or fusion, and transfer of mobile genetic units) only change the structure of the gene itself, and does not supply the biological information to create new protein folds.[11]

            "New protein folds represent the smallest unit of structural innovation that natural selection can select."[12] Building new forms of life must extend beyond individual amino acid sequences if innovation is to take place through Darwinian evolutionary processes. Mutations must not only displace or modify individual genes, but must also introduce new protein folds. This is a problem for evolutionary models, because "…based on the physical principles of protein function, the vast majority of protein functions cannot be performed by unfolded proteins. If mutated such that they unfold, not only do proteins lose their functionality, but they become vulnerable to attack by proteases that devour them."[13] However, a slow process of minute changes over thousands of generations creates functional gaps in the proteins. "Francisco Blanco found that the intermediate sequences lack a well-defined three dimensional structure. Thus, he concluded that the appearance of a completely new fold from an existing one is unlikely to occur by evolution through a route of folded intermediate sequences."[14]

            The functional protein fold limitation is vastly complicated by the improbability of randomly mutating and then selecting an amino acid sequence with a useful function that can then be successfully passed through inheritance. Counting for all plausible trials that can be attempted to create a new protein fold with a distinct new function, Dr. Douglas Axe concluded in the Journal of Molecular Biology that "…the probability of successful protein fold mutations was vanishingly small - if each and every organism that ever lived on Earth received on new gene to pass on to future generations the likelihood of even one successful new novel protein function and fold ever occurring was 1 in 1037."[15]

Coordinated and Interdependent Functionality

            According to evolutionary theory, small incremental changes to functions must be 'captured' through natural selection and passed to succeeding generations. However, any system that depends for its function on the coordinated action of many parts could not be changed gradually through mutation without losing functionality along the way. Thomas Frazzetta notes that "…transitions from one type to the next presumably involve a greater continuity by means of a vast number of intermediate types. Not only must the end product - the final machine - be feasible, but so must all the intermediates. The evolutionary problem is, in a real sense, the gradual improvement of a machine while it is running!"[16]  

            Given the statistical implausibility of aligning two or twenty mutually beneficial mutations simultaneously to produce a beneficial new function, evolutionary scientists contemplated co-option as the answer, even though this still presupposed biological information and only deferred the problem to origin-of-life researchers. "Further research has shown the co-option hypothesis has not been a suitable explanation for coordinated or integrated changes. Axe and Gauger experimented on what was plausible given the time frame available (that life was on the Earth), and showed statistically that the smallest conceivable step needed to co-opt a useful genetic function was not statistically plausible for even one instance to occur."[17]

Body Plans and Macroevolution

            Darwin himself understood that only beneficial variations that can be passed to future generations will be stored in the collective memory of organisms. Yet without beneficial variations, there are no characteristics of the organism for natural selection to operate upon, and without natural selection there is no evolutionary process taking place. Micro evolutionary change is insufficient to produce the scale of changes needed to introduce new phyla and genera, yet no changes to early-acting regulatory genes that are not detrimental or lethal to the organism have ever been observed in mutagenetic laboratory experiments.[18] 

          What is critical for macroevolutionary changes at the level of new organs or body plans is for the expression of genetic mutations very early in the embryological cycle. As evolutionary geneticists Bernard John and George Miklos explain, "macroevolutionary change" requires changes in "very early embryogenesis," as mutations later in the development of an organism will affect relatively fewer cells and tissues.[19] "Thus, mutations that are expressed early in the development of animals have probably the only realistic chance of producing large-scale macroevolutionary changes."[20] 

            To build new proteins, body plans and cell types, first an embryological control system must be in place. During cell differentiation, information is bound to very specific sites in the DNA (called transcriptional regulators), that regulate the expression of genes at specific times in the gestational process. Mutagenic experiments on fruit flies, nematodes, frogs, mice, and sea urchins has repeatedly confirmed that if these genetic information is tampered with through mutations in any way, it almost always renders the developing organism unviable.[21] 

          Research has revealed that non-protein-coding regions of the genome control and regulate the timing and expression of the protein-coding regions of the genome like circuits. Whenever one of these developmental gene regulatory networks (dGRN) is mutated, some process within the embryological development cycle is interrupted or changed that has implications to other parts of the system because of their highly interconnected and hierarchical organization.[22] As Eric Davidson summarizes, "Since these consequences [of a mutation] are always catastrophically bad, flexibility is minimal, and since the subcircuits are all interconnected, the whole network partakes of the quality that there is only one way for things to work. And indeed the embryos of each species develop in only one way."[23]

            Thirty years of mutagenesis experimentation has failed to uncover the mechanism for the right mutations to occur in order to derive new proteins, tissues, organs and body plans. Dr. Meyer explains that "…mutagenesis experiments…have raised troubling questions about the role of mutations in the origin of animal body plans. If mutating the genes that regulate body-plan construction destroy animal forms as they develop from an embryonic state, then how do mutations and selection build animal body plans in the first place? The neo-Darwinian mechanism has failed to explain the generation of new genes and proteins needed for building new animal forms…"[24]  

            Finally there is the issue of epigenetic information. Building new body plans also requires complex information stored in sugars and in the exterior membranes of cells, microtubule arrays, cell membrane patterns and patterns derived from ion channels. All of these sources of epigenetic information are necessary in the development of organisms and are outside of the mutational mechanism proposed by Darwinian evolutionists.[25] Dr. Meyer summarizes: "If DNA isn't wholly responsible for the way an embryo develops - for body-plan morphogenesis ─ then DNA sequences can mutate indefinitely and still not produce a new body plan, regardless of the amount of time and the number of mutational trials available to the evolutionary process.  Genetic mutations are simply the wrong tool for the job at hand."[26]            

The Fossil Record

            Entertaining for a moment the hope positivist materialist neo-Darwinians hold out that a mechanism will yet be discovered that explains both the origin-of-life mystery and the incredibly complex replication instructions of cells, a brief look at the fossil record is warranted. Perhaps if intermediary fossils were found that are predicted by evolutionary models, then it would at least prove evolutionary events happened even if evolutionary biologists cannot explain how these events could have happened. For neo-Darwinian evolutionary theory to be validated, it must reveal a plausible explanation for all the processes and mechanisms needed to evolve new body plans, and complex physical structures such as eyes, wings, feathers, echolocation, blood clotting, skin, amniotic egg, nervous systems, etc., all within the geological 'moment' of time called the Cambrian epoch.

            What does the fossil record actually show? Darwin predicted the 'morphological distance' between classes and phyla would come from diversity of species, to genera, and eventually branch off to form new families. Instead, archeological evidence from the Burgess Shale reveals significant disparity between families without any transitional forms."[27] Ad hoc theories were proposed to excuse the lack of transitional forms such as the Charles Walcott's Lipalian Interval Theory in the 1920's, which argued (without real evidence) that pre-Cambrian fossils were all located in deep sea beds and are yet to be discovered. This theory was rejected once ocean floor subduction was measured globally to be less than 200 million years - which falls in the Jurassic period. 

          This was followed by another conjecture generally referred to as the Artifact Hypothesis.[28] Eric Davidson suggested that pre-Cambrian fossils were simply too small or fragile to survive the fossilization process. Later discoveries in the Warrawoona Group strata in Western Australia showed pre-Cambrian fossils not only exist, but show no relation to Cambrian fossils as their body type precursors. Cheng Jiang pre-Cambrian rocks preserved embryos of sponges, but no hard body ancestors of Cambrian hard body animals were found.[29] How can it be that soft tissue fossils from the pre-Cambrian era survived, but "conveniently," no hard body fossils have been found globally that are accepted as precursor transitional forms for later Cambrian fossils? Statistical paleontologists have shown that the reason there are selective 'gaps' in the fossil record where needed transitional forms should be is not due to the fossils being undiscovered, but due to the high probability they never existed at all.[30]

Other Ad Hoc Explanations

            With the dearth of viable evidence to support neo-Darwinian evolutionary theory, some modern scientists simply ditch the fossil evidence and argue that "…similarities in anatomy and in the sequences of information-bearing biomacromolecules such as DNA, RNA, and protein point strongly to a common ancestor. They also assume that the degree of difference in such cases is on average proportional to the time elapsed since the divergence from a common ancestor."[31] However, this new "Deep Divergence hypothesis" is "deeply" flawed because it presumes a single common ancestor, presumes the Artifact hypothesis which has been discredited, is not supported by the fossil record evidence, and has produced wildly different (and contradictory) outcomes based on which set of molecules were studied and how far back the molecular clock was presumed.[32] "Many paleontologists and evolutionary biologists now concede that the long-sought-after pre-Cambrian fossils, those necessary to document a Darwinian account of the origin of animal life, are missing."[33] 

Weighing the Evidence Fairly

            The scarcity of transitional forms in the fossil record, and the abrupt appearance of many new body types and phyla without precursors should cast doubt on neo-Darwinian evolutionary models that require minute changes over long periods of time.[34] No viable model or explanation for the origin of life comes from neo-Darwinian theories - it is simply presupposed. Neo-Darwinian theories fail to provide an account for missing fossil transitions from this hypothesized universal common ancestor to present day phyla - the "evolutionary tree" is missing the stump and all the major branches.  

          Some evolutionary biologists, such as George Miklos of the Austrian National University, now argue that neo-Darwinism fails to provide a plausible mechanism for macroevolutionary changes.[35] However, contradictory evidence to neo-Darwinist theories has generally been ignored or explained away by its adherents because Darwinian evolution is not just a theory, but a positivist atheist worldview. Consider scientists who apply to themselves the title "Evolutionary Biologist." This reveals just how deep the bias goes.

            Kuhn noted as far back as 1962 that scientists are susceptible to being lured into a paradigm where rigorous empirical validation, falsifiable tests, and contrary evidence is no longer accepted or simply ignored because it is counter to their worldview.[36] This is why the theory of evolution is considered a "fact" by many in the scientific community when it has been thoroughly discredited by actual data and experimental analysis. Consideration of alternative mechanisms such as Intelligent Design are denied by science "…not by its conclusions, but by its methodological starting point that modern science excludes direct creation."[37] The neo-Darwinist worldview has been discredited by Darwin's own validation criteria and needs to be replaced with a more powerful "alternative competing hypothesis."
                         

Bibliography


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Berlinski, David, The Devil's Delusion: Atheism and Its Scientific Pretensions, (New York NY: Crown Forum, 2008)

Budd, Graham and Jensen, Sôren, "A Critical Reappraisal of the Fossil Record of the Bilaterian Phyla," Biological Reviews of the Cambridge Philosophical Society 75 (2000)

Davidson, Eric, Evolutionary Bioscience as Regulatory Systems Biology, Developmental Biology: 357 (2011)

Dembski, William A., Intelligent Design: The Bridge between Science & Theology, (Downers Grove, IL: InterVarsity, 1999)

Frazzetta, Thomas, Complex Adaptations in Evolving Populations, (Sunderland, MA: Sinauer, 1975)

Gitt, Werner, In the Beginning was Information, (Green Forest, AR: First Master Books, 2005)

Gonzalez, Guillermo, and Jay Wesley Richards, The Privileged Planet: How Our Place in the Cosmos Is Designed for Discovery, (Washington, DC: Regnery Pub., 2004)

Meyer, Stephen, Darwin's Doubt: The Explosive Origin of Animal Life and the Case for Intelligent Design, (New York, NY: HarperCollins Books, 2013)

Nelson, Paul and Wells, Jonathan, "Homology in Biology: Problem for Naturalistic Science and Prospect for Intelligent Design," In Darwinism, Design and Public Education, edited by J. A. Campbell and S. C. Meyer, 303-322, (East Lansing: Michigan State Univ Press, 2003)

Ratzch, Del, The Battle of Beginnings: Why Neither Side is Winning the Creation-Evolution Debate, (Downers Grove, IL: InterVarsity Press, 1996)

Thompson, K. S., "Macroevolution: The Morphological Problem," American Zoologist 32 (1992).

Witham, Larry, By Design: Science and the Search for God, (San Francisco: Encounter, 2003)






[1] Meyers, Darwin's Doubt, p 3 [paraphrased]
[2] Meyers, Darwin's Doubt, p ix
[3] Meyers, Darwin's Doubt, p viii
[4] Witham, By Design, p 103
[5] Witham, By Design, p 103
[6] Meyer, Darwin's Doubt, p. 217 [paraphrased]
[7] Meyer, Darwin's Doubt, p. 218 [paraphrased]
[8] Meyer, Darwin's Doubt, pp 215-216 [summarized]
[9] Gitt, In the Beginning was Information, p 192
[10] Gitt, In the Beginning was Information, p 194
[11] Meyer, Darwin's Doubt, pp 221-229 [synthesized and summarized]
[12] Meyer, Darwin's Doubt, p 191
[13] Meyer, Darwin's Doubt, p 196
[14] Meyer, Darwin's Doubt, p 197
[15] Axe, Journal of Molecular Biology 301, p 585  [emphasis added]
[16] Meyer, Darwin's Doubt, pp 232 quoting Frazzatta, Tom Complex Adaptations in Evolving Populations, p 20
[17] Meyer, Darwin's Doubt, pp 254
[18] Meyer, Darwin's Doubt, pp 254 [paraphrasing Sôren Lôvtrup].
[19] Meyer, Darwin's Doubt, pp 259
[20] Meyer, Darwin's Doubt, p 259  [quoting K S Thompson, American Zoologist]
[21] Meyer, Darwin's Doubt, p 256  [quoting Eric Wieschaus who lectured at the 1982 meeting of the American Association for the Advancement of Science)
[22] Meyer, Darwin's Doubt, pp 319-320 [summarized]
[23] Davidson, Evolutionary Bioscience, p 40
[24] Meyer, Darwin's Doubt, p 257
[25] Meyer, Darwin's Doubt, p 273 [paraphrasing Nelson and Wells, Homology]
[26] Meyers, Darwin's Doubt, p 281
[27] Meyers, Darwin's Doubt, p 40-44 [summarized]
[28] Meyers, Darwin's Doubt, p 57-62 [summarized]
[29] Meyers, Darwin's Doubt, p 63-64 [summarized]
[30] Meyers, Darwin's Doubt, p 93-97 [summarized
[31] Meyers, Darwin's Doubt, p 100
[32] Meyers, Darwin's Doubt, p 101-109 [summarized]
[33] Meyers, Darwin's Doubt, p 101 [quoting Budd and Jensen, pp 253-295]
[34] Meyers, Darwin's Doubt, p 17 [summarized]
[35] Meyers, Darwin's Doubt, p 287
[36] Ratzsch, The Battle of Beginnings, p 103ff
[37] Berlinski, The Devil's Delusion, p 60-61 [quoting C. F. Wiezsacker, The Relevance of Science]

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