Re: Is evolution unscientific? From: pdlaunt@nando.net (PDLaunt) Perhaps the weakest link in Miller's 1953 and subsequent experiments is the "trap" which serves to simulate the primordial ocean or "pool" of water where life first arose by spontaneous generation. Such a water trap is perhaps the least likely of any place for life to have begun by spontaneous generation. Why? Experiments by Miller and others supported the general conviction among experts that amino acids, which represent the building blocks and basis of life, were formed by chance - normal, unguided, non-teleonomic chemical reactions. In the hypothesized primeval atmosphere consisting of water vapor, ammonia, methane, nitrogen and carbon dioxide, electrical discharges (lightning) took place, whereby small amounts of various biologically essential amino acids were spontaneously synthesized. Miller's experiments did produce small but definite amounts of the building blocks of life (amino acids) (Formula I) and, according to "expert" opinion he had thus solved the problem of the origin of the first biologically essential amino acids. {Wrong} FORMULA [I] NH2 | CH4 + H20 + NH4 + energy -----> R - CH - COOH (methane + water + ammonia + lightning = amino acid) Now if such amino acids dissolve in water under favorable chemical conditions, any two of them will allegedly combine, releasing a molecule of water and forming a peptide (Formula II) [II] Condensation reaction R - CH - COOH + R1 - CH - COOH <------ R - CH - COOH | | -------> | NH2 NH2 NH - CO - CH - R1 + H20 | NH2 (amino acid 1 + amino acid 2 combine to give peptide + water) The amino group (NH2) of the amino acid (R=radical) combines with the carboxyl group (COOH) of the second amino acid, releasing HOH to form the peptide. Upon examination of the formula for peptides, one finds that they always carry an additional NH2 grou p and a COOH group so that the dipeptide, for example, can combine with a second dipeptide (or monopeptide or amino acid) to form a quadripeptide (or tripeptide, etc.) (Formula III). Again, a molecule of water is released in these condensations. [III] R - CH - COOH + R - CH - COOH | | NH - CO - CH - R1 NH - CO - CH - R1 | | NH2 NH2 ^ 1. || Condensation 2. || reaction || || v R1 | R - CH - CO - NH - CH - CO - NH - CH - COOH + H2O | NH - CO - CH - R1 3. | NH2 (peptide 1 + peptide 2 combine to give tripeptide 3 plus water) If further reactions take place between polypeptide molecules one finally obtains proteins similar to those of life - after the chain has reached a length of several thousand amino acids Since many types of amino acids can be obtained spontaneously in the hypothesized primeval atmosphere with the aid of electric discharges (Miller and others did proven this), and amino acids in aqueous solution are said to combine spontaneously (according to equations II and III) to give peptides, polypeptides, and protein-like substances, an experimental basis for spontaneous biogenesis has thus been established, according to the experts. The building blocks of life (amino acids) and peptides (basis of proteins) are both produced spontaneously, according to Miller's scheme, from energy and matter with no help from extramaterial teleonomy. Most textbooks imply, or state openly that the way has now been cleared for the postulate of a chance spontaneous origin of life on a scientific basis. Given energy and a primeval atmosphere, living protoplasm, followed by the whole tree of life, *must* eventually appear spontaneously and automatically. Example: According to Oparin, a microsphere or coacervate (primitive cell which begins to replicate by means of cell division) will eventually be formed once a sufficient amount of vital protein exists within a primeval ocean (THE TRAP). Beyond this state, natural selection allegedly will provide automatic development without help of any external teleonomy and this progression leads all the way to Homo sapiens. Lets test the scientific feasibility of the above generally accepted propositions. A. Spontaneous Biogenesis in Primeval Oceans Could biogenesis have occurred spontaneously from amino acids and polypeptides according to the above referenced equations (I-III)? Your Biology textbooks probably stated that this is the case. But even a superficial chemical examination of the equation s provides a definitive negative reply. The reactions in equations (I-III) are *reversible* The direction in which the reaction takes place depends on the concentration of reagents on both sides of the equation. If the molecules of water which have been released by the condensation reaction o n the right hand side of the equation are removed as soon as they appear, and their concentration is thus reduced in the reacting mixture, the entire reaction should tend toward the right hand side, and the theoretical yield of peptides - as represented i n the equations - be obtained. The converse is true. Adding large amounts of water to the reaction mixture will drive the reaction to the left hand side and no peptides, or only a very few will be formed (depending upon the amount of water): instead, th e initial reagents, amino acids, are obtained (II). So, if excess water is present in the reacting mixture, peptide synthesis does *not* take place, equilibrium remains on the side of the initial reagents, the amino acids, which are the building blocks o f life. Put another way: according to the law of mass action which is valid for all reversible reactions, synthesis of polypeptides from amino acids does not take place in the presence of excess water. The trap in Miller's experiments is rendered useless. The consequence of this well-known fact of organic chemistry is: concentrations of amino acids will combine only in minute amounts, if they combine at all in a primeval ocean (THE TRAP) providing excess water, to form polypeptides. Any amounts of polypeptide which might be formed will be broken down into their initial components (amino acids) by the excess water. The ocean (TRAP) is therefore practically the last place on this or any other planet where proteins for life could be formed spontaneously fro m amino acids. But there are even worse problems for biogenesis as currently postulated, not the least of which is chirality. * Chirality of amino acids - laevorotary molecules differ structurally from dextrorotary molecules but *not* in chemical analysis. The three-dimensional properties (chirality) of the amino acids determines the properties of the resulting proteins: l-pro teins, d-proteins and dl-proteins. The stereostructure of proteins which contribute to living protoplasm are, almost without exception, laevorotary. Laevorotary chirality in the amino acids of life is an absolute necessity; d-forms are simply incapable of supporting life. But this chiral specificity goes even further. Whereas the amino acids of the living proteins are laevorotary, all nucleic acids exhibit an exclusive dextro configuration. From this it becomes obvious that amino acids which are to act as the building blocks of life at biogenesis must exhibit the correct chirality. For biogenesis to take place, all building blocks must be of the l-form with *no* dextrorotary isomers. The amino acids produced by Miller, et. al. are exclusively and entirely racemates - 50% l-form and 50% d-form. Likewise, amino acids formed by lightning, or other non-biological processes appear as racemates. No method is known to present-day science by means of which inorganic random processes resolve from racemates pure laevo- or pure dextrorotary forms. Hence it is scientifically erroneous to state that Miller's experiments have made possible the synthesis of life by natural processes and chance, or even to suggest that they have. A.E. Wilder-Smith, "The Natural Sciences Know Nothing of Evolution" - 1981, pp 11-21 End**************************************************************************