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The following are previously unclassified quotes about Mechanisms, now classified under that heading, and under subheadings alphabetically by author and date, as a temporary intermediate step towards integrating them into my quotes pages proper.
"Animal and plant species are usually immediately amenable to selective breeding, and breeders detect no evidence of any intrinsic, anti-evolution forces. If anything, selective breeders experience difficulty after a number of generations of successful selective breeding. This is because after some generations of selective breeding the available genetic variation runs out, and we have to wait for new mutations." (Dawkins, Richard [zoologist and Professor for the Public Understanding of Science, Oxford University], "The Blind Watchmaker," [1986], Penguin: London, 1991, reprint, p.247).
"No amount of argument, or clever epigram, can disguise the inherent improbability of orthodox theory; but most biologists feel it is better to think in terms of improbable events than not to think at all; there will always be a few who feel in their bones a sneaking sympathy with Samuel Butler's scepticism: `... there must have been a little cheating somewhere with these accidental variations [mutations] before the eagle could have become so great a winner'. How far the heathen will be converted by Dr. Huxley is difficult to say." (Gray, Sir James [late Professor of Zoology, Cambridge University], "The Case for Natural Selection." Review of "Evolution in Action," by Julian Huxley, Chatto & Windus: London, 1953, in Nature, Vol. 173, No. 4397, February 6, 1954, p.227).
"The more perfect a structure is, the more certain that any random tinkering will be harmful. Even if a piano factory had a very large output of pianos, it could not tune them by giving a monkey a wrench and letting it play with the pegs that hold the strings tight, discarding any instrument untuned. The more exact is the tuning needed, the larger is the proportion that would have to be junked; rarely indeed would the monkey improve a well-tuned instrument. Moreover, junking pianos made nonfunctional would not suffice. If the monkeys jiggered the posts a bit but not enough for the instruments to be discarded, all pianos would become slightly or eventually seriously untuned. That is, the organ would degenerate. This analogy falls short of reality because the well-fashioned eye, for example, is more than a single instrument. It has coordinated systems for tracking, focusing, light control, light registration color perception, and incipient image formation, all of which can anal do sometimes go wrong. An additional complication is that genes have multiple effects, and it is always possible that a gene needed elsewhere may have negative consequences for the eye. It would seem difficult for simple selection to maintain the detailed structure of large gene control networks such as must be responsible for such an intricately integrated organ as the eye, unless the pattern is somehow self-regulatory. Random changes would overwhelm a rather large selection rate, limiting the number of genes that can be maintained as a group (Winstatt and Schank 1988, 239-250). A combination of many genes would be vulnerable to deleterious mutations disturbing the delicate harmony if the structure did not have great powers of repairing mistakes." (Wesson R.G., "Beyond Natural Selection," [1991], MIT Press: Cambridge MA, 1994, reprint, p.81).
"A century is a fantastically short period of cosmic time, and all sorts of queer, exciting and improbable things may happen in five hundred million years; so, if we accept 'possibility' as a basis for scientific thought, why worry? Dr. Huxley admits quite frankly: `No one would bet on anything so improbable happening; and yet it has happened. It has happened thanks to the workings of Natural Selection and the properties of living substance which make Natural Selection inevitable'. What more can be said, except possibly to suggest that there may be a slight difference between something that 'has happened' and one which 'may have happened'." (Gray, Sir James [late Professor of Zoology, Cambridge University], "The Case for Natural Selection." Review of "Evolution in Action," by Julian Huxley, Chatto & Windus: London, 1953, in Nature, Vol. 173, No. 4397, February 6, 1954, p.227. Emphasis in original).
"Natural selection remains still a vera causa in the origin of species; but the function ascribed to it is practically reversed. It exchanges its former supremacy as the supposed sole determinant among practically indefinite possibilities of structure and function, for the more modest position of simply accelerating, retarding, or terminating the process of otherwise determined change. It furnishes the brake rather than the steam or the rails for the journey of life; or in better metaphor, instead of guiding the ramifications of the tree of life, it would, in Mivart's excellent phrase, do little more than apply the pruning knife to them. In other words, its functions are mainly those of the third Fate, not the first, of Siva, not of Brahma.-PATRICK GEDDES and J. ARTHUR THOMPSON, "Evolution." New York, Home University Library, 1911, p. 248." (Henderson, Lawrence J. [late Professor of Biological Chemistry, Harvard University], "The Fitness of the Environment: An Inquiry into the Biological Significance of the Properties of Matter," [1913], Beacon Press: Boston MA, 1958, reprint, pp.274-275).
"The theory of natural selection implies the survival of organisms possessing functional advantages over their predecessors or rivals. Strange as it may seem, one immediate effect of the `Origin' was a marked recession in the study of animal function. There was, and still is, a tendency for morphologists to ascribe to organs and structures functional significance for which there was, or is, little observational evidence. In this respect `Evolution in Action' is by no means guiltless; it goes a considerable way beyond the physiological facts. Is Dr. Huxley quite sure that the loss of the lateral digits by the ancestors of the horse gave them an `additional turn of speed'?" (Gray, Sir James [late Professor of Zoology, Cambridge University], "The Case for Natural Selection." Review of "Evolution in Action," by Julian Huxley, Chatto & Windus: London, 1953, in Nature, Vol. 173, No. 4397, February 6, 1954, p.227).
"There are six major gaps in our knowledge and understanding of natural selection: (1) Why does natural selection occur? What are the biological reasons for the process, and what conditions favor natural selection? (2) How does it occur? What are the mechanisms of natural selection? What is the form of the separation line or selection function? (3) What kinds of traits are most likely to be affected by natural selection? (4) What is the effect of simultaneous natural selection on many traits, some of them intercorrelated with each other? What is the effect of genetic interactions among traits? What is the effect of phenotypic (selective) interactions among traits? Is there any limit to the number of traits that affect fitness, and does this vary with habitat? (5) Given that there is known fitness variation, what are the evolutionary dynamics and equilibrium configurations (if any) of the traits? (6) Is there a relationship between the presence of demonstrable natural selection and genera that are currently radiating rapidly?" (Endler J.A., "Natural Selection in the Wild," Princeton University Press: Princeton NJ, 1986, p.247).
"A second class of objections relates to the difficulty of imagining functional intermediate stages in the development of a character such as the electric organ of a fish, or rather similarly, to the acquisition of organs of "extreme perfection" such as the vertebrate eye. In general, specific difficulties like these tend to diminish as comparative studies progress and advantageous (functional) intermediate stages are discovered. Moreover, as Fisher has pointed out, evolutionists could not explain the production of complex organs except by postulating natural selection, for the probability of all the necessary modifications appearing initially in one organism (except by special creation) is virtually zero. It is only their gradual accumulation as the result of natural selection, which increases sufficiently the probability of their appearing in the same individual that make it possible for highly integrated systems to be evolved." (Berry R.J., "Teach Yourself Genetics," The English Universities Press: London, 1965, p.116) .
"In order to build up a structure by natural selection, it is essential that each stage in the building process must make an animal better fitted to its environment than the one before it. An eye that is half developed must be more useful to an animal than an eye that is 49 per cent developed, and this in turn, than one, the development of which has proceeded to only 48 per cent, and so on. The graph of usefulness against the extent of structural organization must show a steady upward rise- otherwise progress must inevitably stop, hindered by natural selection itself. If the graph is not a steady upward rise, but has ups and downs, then natural selection (which selects usefulness and adaptation), working from either direction, will force the organism to the nearest maximum. Today, with our much greater knowledge of and familiarity with complex systems, we know that steady upward rises of the kind demanded by materialistic evolutionists are unknown to science. Isolated fundamental changes make a machine less efficient than it was before and may even make it useless, unless, indeed, numerous other adaptations are made at the same time. The radio manufacturer cannot turn one model of a wireless set into a larger and better one by continuous stages-he cannot add a new valve, a condenser, a piece of wire, etc., in a series of operations, and hope each time to obtain a model that is slightly better than the one before. All the changes must be made at once-or not at all! To add an extra valve to a wireless set you must first cut through wires, disconnect the loudspeaker, etc., and at once the set becomes useless as a functioning whole. Only after passing through the useless stage can it be made more useful than before. It is the same with all arrangements of matter organised as functioning units. To ask for a gradual, uniform, improvement is, it seems, to ask for the impossible." (Clark, Robert E.D.* [Senior Lecturer in Chemistry, Cambridgeshire College of Arts and Technology], "The Universe: Plan or Accident?: The Religious Implications of Modern Science," [1949], Paternoster: London, Third Edition, 1961, pp.123-124).
"There is no fault to be found with Mr. Darwin's method, then; but it is another question whether he has fulfilled all the conditions imposed by that method. Is it satisfactorily proved, in fact, that species may be originated by selection? that there is such a thing as natural selection? that none of the phenomena exhibited by species are inconsistent with the origin of species in this way? If these questions can be answered in the affirmative, Mr. Darwin's view steps out of the ranks of hypotheses into those of proved theories; but so long as the evidence at present adduced falls short of enforcing that affirmation, so long, to our minds, must the new doctrine be content to remain among the former-an extremely valuable, and in the highest degree probable, doctrine, indeed the only extant hypothesis which is worth anything in a scientific point of view; but still a hypothesis, and not yet the theory of species." (Huxley T.H., "Darwin on the Origin of Species," Westminster Review, April 1960, in Rhys E., ed., "Man's Place in Nature and Other Essays", [1863], Everyman's Library, J.M. Dent & Co: London, 1906, reprint, p.333).
"To say that a new adaptation necessarily arose through natural selection is an incomplete description, a tautology, and a misrepresentation of natural selection, adaptation, and evolution. Natural selection addresses the problem of the spread of new variants or new adaptations, not their origin. ... Natural selection cannot explain the origin of new variants and adaptations, only their spread." (Endler J.A., "Natural Selection in the Wild," Princeton University Press: Princeton NJ, 1986, pp.46,51. Emphasis in original).
"After much consideration, and with assuredly no bias against Mr. Darwin's views, it is our clear conviction that, as the evidence stands, it is not absolutely proven that a group of animals, having all the characters exhibited by species in nature, has ever been originated by selection, whether artificial or natural. Groups having the morphological character of species, distinct and permanent races in fact, have been so produced over and over again; but there is no positive evidence at present that any group of animals has, by variation and selective breeding, given rise to another group which was even in the least degree infertile with the first." (Huxley T.H., "Darwin on the Origin of Species," Westminster Review, April 1960, in Rhys E., ed., "Man's Place in Nature and Other Essays", [1863], Everyman's Library, J.M. Dent & Co: London, 1906, reprint, p.333).
"The neo-Darwinists deny that physical surroundings can give rise to new species; they may bring about changes in an organism, but the acquired characteristics are not inheritable. Can, then, natural selection or competition with other animals create new species? The classic example of a giraffe with the longest neck surviving when leaves are left only high on the trees does not prove that giraffes with longer necks would become a separate species. And, in any event, under the described conditions no new race would ever evolve: the female giraffe, which are smaller in stature, would die out before the male competitors, and there would be no progeny; but should there be progeny, the young giraffes would probably die because they would be unable to reach the leaves." (Velikovsky I., "Earth in Upheaval," [1950] Abacus: London, 1978, reprint, p.211).
"Consider the well-known example of industrial melanism in the British peppered moth, Biston betularia. Few high school biology texts fail to mention this study yet few students (and almost no Creationists) seem to understand what it is that this example demonstrates. ... Clearly, environmental pressures, through natural selection, can effect rapid shifts in the genotype of a population. In this case the spontaneously produced variation that proved to be advantageous to the species' survival was a genetic mutation. This is evolution in action, under observation. What it is not (nor was it ever claimed to be despite what one may find in Creationist literature) is an example of the evolution of a new species." (Archer, Michael [Professor, School of Zoology, University of New South Wales], "The Reality of Organic Evolution," in Selkirk, D.R. & F.J. Burrows, eds., "Confronting Creationism: Defending Darwin," New South Wales University Press: Kensington, NSW, Australia, 1988, pp.30-31).
"Some experiments are said to demonstrate evolution in action; those on industrial melanism in moths are a well- known example. Melanic forms are dark-coloured or black individuals normally forming a small minority in a population of comparatively light-coloured moths; in industrial districts where tree-trunks are blackened by soot melanic forms predominate because they are less conspicuous when sitting on a dark background. The experiments show the effects of predation on the survival of the dark and of the normal forms of the Peppered Moth in a clean environment and in one polluted by smoke. The experiments beautifully demonstrate natural selection-or survival of the fittest-in action, but they do not show evolution in progress, for however the populations may alter in their content of light, intermediate or dark forms, all the moths remain from beginning to end Biston betularia." (Matthews L.H., "Introduction," in Darwin C.R., "The Origin of Species," [1872], Everyman's University Library: J.M. Dent & Sons: London, 1972, reprint, p.xi).
"Natural selection is a bewilderingly simple idea. And yet what it explains is the whole of life, the diversity of life, the complexity of life, the apparent design of life. It all flows from this one remarkably simple idea." (Dawkins, Richard [zoologist and Professor for the Public Understanding of Science, Oxford University], "Mechanisms of Evolution," in Campbell N.A., Reece J.B. & Mitchell L.G., "Biology," [1987], Benjamin/Cummings: Menlo Park CA, Fifth Edition, 1999, p.413).
"But the significance of hopeful monsters, if they exist, is that they seem to flout the law of natural selection. They are subject to it in a general sense: better monsters will, over the long run, drive out weaker ones. But the mutation need not represent an advance in fitness; a mutant gene can spread throughout the population even if it carries no particular survival value, as long as it is not markedly harmful. The web-footed salamanders have no obvious advantage over their digited relatives, but they evolved right along anyway. Among hyenas, a mutation has given rise to a species in which the female develops a useless set of male sexual organs. The iron law of Darwinism-that each new species represents an advance in fitness over its predecessor-seems to have been breached." (Adler, Jerry & Carey, John [journalists], "Is Man a Subtle Accident?," Newsweek, November 3, 1980, pp.54-55,p.55).
"Natural selection is free of tautology in any formulation that recognizes the causal interaction between the organism and its environment, but most recent critics have already understood this and are actually arguing that the theory is not falsifiable in its operational form. Under examination, the operational forms of the concepts of adaptation and fitness turn out to be too indeterminate to be seriously tested, for they are protected by ad hoc additions drawn from an indeterminate realm. Future knowledge may reduce the organism to a determinate system, but until such time too little is known to investigate organism-environment relations. Researchers should consider whether natural selection is necessary to empiric investigation in their area, and whether it can serve the purpose for which it is applied." (Brady R.H., "Natural selection and the criteria by which a theory is judged," Systematic Zoology, Vol. 28, 1979, pp.600-621, p.600).
"Since tautology is fatal for any sort of causal explanation, it is somewhat mysterious to find a number of authors advancing an admittedly tautologous formulation of natural selection. Waddington, for example, published the following passage in 1960: `Natural selection, which was at first considered was though it were a hypothesis that was in need of experimental or observational confirmation, it turns out on closer inspection to be a tautology, a statement of an inevitable although previously unrecognized relation. It states that the fittest individuals in a population (defined as those which leave the most offspring) will leave the most offspring. Once the statement is made, its truth is apparent. This fact in no way reduces the magnitude of Darwin's achievement, only after it was clearly formulated, could biologists realize the by enormous power of the principle as a weapon of explanation.' [Waddington, C. H. 1960. "Evolutionary adaptations." In Tax, S. (ed.), "The evolution of life". University of Chicago Press, p. 385.] Macbeth (1971) found this passage "staggering." It is even more astonishing to reflect that Macbeth's reaction was not common one. The passage above defines fitness as *leaving the most offspring*. It then states that the fittest individuals will leave the most offspring, and it calls this statement `a weapon of explanation.'" (Brady R.H., "Natural selection and the criteria by which a theory is judged," Systematic Zoology, Vol. 28, 1979, pp.600-621, p.603. Emphasis in original).
"On one point all biologists are agreed: the basic concept of organic evolution has, for a century, stood unrivalled as a contribution to biological thought. As a working hypothesis it opened up and exploited vast new fields of paleontological, anatomical and embryological inquiry. The status of natural selection is not quite so high. True, it is the only theory we have; but when judged as a working hypothesis it is disappointing to find so little advance in a hundred years." (Gray, Sir James [late Professor of Zoology, Cambridge University], "The Case for Natural Selection." Review of "Evolution in Action," by Julian Huxley, Chatto & Windus: London, 1953, in Nature, Vol. 173, No. 4397, February 6, 1954, p.227).
"The camel and the llama are two closely related species with different habitats, the camel living in the plains and the llama high up in the Andes. The camel has a hemoglobin with an oxygen affinity that is normal for an animal of its size, but because of a single mutation in the gene coding for one of the two globin chains that make up the hemoglobin molecule, the llama has a hemoglobin with an unusually high oxygen affinity. That variant hemoglobin helps the llama to breathe in the rarified mountain air. The Harvard geneticist Richard Lewontin pointed out to me that this mutation is likely to have occurred before llamas discovered that they were able to graze at altitudes barred to competing species. In other words, a mutation adapting a species to a new environment is likely to have preceded occupation of that environment." (Perutz M.F., "Is Science Necessary?: Essays on Science and Scientists," [1989], Oxford University Press: Oxford UK, 1991, reprint, p.220. Emphasis in original).
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Created: 27 November, 2002. Updated: 7 July, 2005.