Tuesday, July 18, 2006

"Instant" Evolution Seen in Darwin's Finches, Study Says #1

"Instant" Evolution Seen in Darwin's Finches, Study Says, National Geographic, Mason Inman, July 14, 2006 ... [Graphic: A large ground finch (Geospiza magnirostis) and in inset a medium ground finch (G. Fortis) on Daphne Major island, Galapagos: National Geographic.

Also in ABC/Discovery News, Boston Globe, Chicago Tribune, CNN, LA Times, Livescience & Nature News, as well as the abstract of the original paper in Science . I may comment on those other articles in further post(s), after I finish working through this National Geographic article, if they add something extra of interest.]

Evolution may sometimes happen so fast that it's hard to catch in action, a new study of Galápagos finches suggests. [In both the title and here "evolution" evidently means: 1) the entire process that brought about the origin of finches; birds and all of life. As we shall see, this is another example of how Darwinists employ their fundamental Fallacy of Equivocation on the word "evolution" (and its cognates), i.e. "the deliberate" (or deluded) "confusing of two senses of a term", "in order to maintain [their] political, cultural and intellectual authority":

"Now it is the design theorists' contention that the Darwinian establishment, in order to maintain its political, cultural and intellectual authority, consistently engages in a fallacy of equivocation when it uses the terms creation and evolution. The fallacy of equivocation is the fallacy of speaking out of both sides of your mouth. It is the deliberate confusing of two senses of a term, using the sense that's convenient to promote one's agenda. For instance, when Michael Ruse in one of his defenses of Darwinism writes, `Evolution is a fact, fact, FACT!' [Ruse, M., "Darwinism Defended," Addison-Wesley: Reading MA, 1982, p.58] how is he using the term evolution? Is it a fact that organisms have changed over time? There is plenty of evidence to confirm that organisms have experienced limited change over time. Is it a fact that the full panoply of life has evolved through purposeless naturalistic processes? This might be a fact, but whether it is a fact is very much open to debate.' (Dembski, W.A., "Intelligent Design: The Bridge Between Science and Theology," InterVarsity Press: Downers Grove IL, 1999, p.115. Emphasis original)

As Phillip E. Johnson pointed out, "a single term - `evolution' - is used to designate processes" from "A shift in the relative numbers of dark and light moths in a population" to "the creative process that produced the cell, the multicellular organism, the eye, and the human mind":

"Much confusion results from the fact that a single term- `evolution'-is used to designate processes that may have little or nothing in common. A shift in the relative numbers of dark and light moths in a population is called evolution, and so is the creative process that produced the cell, the multicellular organism, the eye, and the human mind. The semantic implication is that evolution is fundamentally a single process, and Darwinists enthusiastically exploit that implication as a substitute for scientific evidence. Even the separation of evolution into its `micro' and `macro' varieties- which Darwinists generally resist-implies that all the creative processes involved in life comprise a single, two-part phenomenon that will be adequately understood when we discover a process that makes new species from existing ones. Possibly this is the case, but more probably it is not. The vocabulary of Darwinism inherently limits our comprehension of the difficulties by misleadingly covering them with the blanket term `evolution.'" (Johnson, P.E., "Darwin on Trial," [1991], InterVarsity Press: Downers Grove IL, Second edition, 1993, pp.69-70)

Researchers from New Jersey's Princeton University have observed a species of finch in Ecuador's Galápagos Islands that evolved to have a smaller beak within a mere two decades. [And here "evolution" (i.e. "evolved") means 2) a minor change in a single characteristic ( i.e. beak size) in a species of finch.]

... Surprisingly, most of the shift happened within just one generation, the scientists say. [Therefore it cannot be the Darwinian process of favourable allele(s)in a given environment replacing unfavourable allele(s), i.e. for small beak size, in a population. That, by definition requires the finches bearing the unfavourable allele(s) to die without offspring and then the finches bearing the favourable allele(s), i.e. for large beak size to breed up.

In fact, Neo-Darwinist mathematician and geneticist J.B.S. Haldane, in a discovery named "Haldane's Dilemma", found that for "the typical higher vertebrate ... over the long term, the average rate of gene substitution is no better than one gene" i.e. at each locus "every 300 generations" (my emphasis):

"In the 1950s the evolutionary geneticist, J.B.S. Haldane, calculated the maximum rate of genetic change due to differential survival. He reluctantly concluded there is a serious problem here, now known as Haldane's Dilemma. [Haldane, J.B.S., "The Cost of Natural Selection," Journal of Genetics, Vol. 55, pp.511-524] His calculations show that many species of higher vertebrate could not plausibly evolve in the available time. ... Differential survival is required for selective gene substitution, and this causes genetic death. There is no way around it. Some individuals must live, and others must die without heirs. The substitution of a gene incurs some number of deaths. We divide this by the number of survivors who reproductively 'pay' for the genetic deaths, and the ratio is called the cost of substitution. ... Haldane found the cost of gene substitution is reduced if the replacement is slower, over more generations. Thus, the cost is lower if the selection coefficients are smaller. He found the cost is minimized and becomes nearly constant for all selection coefficients less than ten percent (s < 0.1), which is said to cover most evolution. The selection coefficients need not remain constant during gene substitution, but may vary. As long as s is less than 0.1 then the cost is kept constant and at a minimum. ... Haldane estimated that over a variety of circumstances the substitution of a gene incurs an average cost of thirty (Cs = 30). ... Haldane then surveyed the capacity of higher vertebrate species to pay the various costs. He estimated that averaged over the long term these species have a reproductive excess of one tenth (Ps = 0.1). This means the typical higher vertebrate can reproduce an additional one tenth its population size each generation and devote this excess specifically (and with perfect efficiency) to paying the cost of substitution. In summary, the cost of substitution Cs is 30 and it is paid off in installments (Ps) of 0.1 each generation. At that rate it takes (Cs + Ps) 300 generations to pay the cost of substituting one gene. Haldane's conclusion was clear: over the long term, the average rate of gene substitution is no better than one gene every 300 generations. This does not mean these substitutions occur sequentially, one by one. Several genes can undergo substitution simultaneously at various speeds. If you average all these speeds, then the total rate can be one per 300 generations. Over the long term, a faster rate than this is not plausible- the species cannot plausibly pay the cost." (ReMine, W.J., "The Biotic Message: Evolution Versus Message Theory," St. Paul Science: Saint Paul MN, 1993, pp.208, 215-216)

Oxford evolutionary biologist Mark Ridley confirmed that for "the theory of evolution by natural selection ... A mutant that produces on average 1 per cent more offspring than its alternative allele ... would take 4,266 generations to increase in frequency from 0.1 per cent to 99.9 per cent of the population":

"The rate of evolution is easily defined. It is simply the amount of change in a trait divided by the time the change took. ...Rates of evolution could also be used to test the theory of evolution by natural selection. Natural selection takes time. For a mutant to increase in frequency from its initial rare state to become the normal gene in the whole population may take a few thousand generations. The exact amount of time can be calculated from equations first derived by J.B.S. Haldane in 1924; it depends on the gene's initial frequency and its selective advantage. A mutant that produces on average 1 per cent more offspring than its alternative allele, for instance, would take 4,266 generations to increase in frequency from 0.1 per cent to 99.9 per cent of the population. If the selective advantage of a particular change in a particular trait were known, Haldane's equation would predict how fast it should evolve under natural selection. The prediction could in principle be tested. In practice, no strong test of this kind has ever been possible. The evidence is not good enough. Our knowledge of genetics and selective advantages is too weak, let alone the quality of fossil evidence. The selective advantages of most evolutionary changes are probably not much more than a few per cent (and probably much less). We can predict that evolution should never go faster than such a selective advantage would allow. In fact the rates of evolution observed in the fossil record are well below that limit. This provides a test of Darwinism, for evolution could possibly go faster than Darwinism allows, and if it did we should need another theory: the fact that the rates are not too fast is evidence for the Darwinian theory. But the test is imprecise; the range of facts allowed by the theory is very wide. (Ridley, M., "The Problems of Evolution," Oxford University Press: Oxford UK, 1985, pp.121-122)

Darwin himself emphasised that "natural selection is a slow process":

"Lastly, natural selection is a slow process, and the same favourable conditions must long endure in order that any marked effect should thus be produced." (Darwin, C.R., "The Origin of Species By Means of Natural Selection," 1872, Sixth Edition, Senate: London, 1994, p.180)

"Why should not Nature take a sudden leap from structure to structure? On the theory of natural selection, we can clearly understand why she should not; for natural selection acts only by taking advantage of slight successive variations; she can never take a great and sudden leap, but must advance by short and sure, though slow steps." (Darwin, 1872, p.156)

Therefore, I assume that this change is not even Darwinian natural selection of random micromuations, but is in fact an example of "phenotypic plasticity", i.e. "The ability of an organism with a given genotype to change its phenotype in response to changes in the environment":

"Phenotypic plasticity ... The ability of an organism with a given genotype to change its phenotype in response to changes in the environment is called phenotypic plasticity. Such plasticity in some cases expresses as several highly morphologically distinct results; in other cases, a continuous norm of reaction describes the functional interrelationship of a range of environments to a range of phenotypes. Organisms of fixed genotype may differ in the amount of phenotypic plasticity they display when exposed to the same environmental change. Hence phenotypic plasticity can evolve and be adaptive if fitness is increased by changing phenotype. Immobile organisms such as plants have well developed phenotypic plasicity giving a clue to the adaptive significance of phenotypic plasticity. A highly illustrative example of phenotypic plasticity is found in the social insects, colonies of which depend on the division of their members into distinct castes, such as workers and guards. Individuals in separate castes differ dramatically from one another, both physically and behaviorally. However, the differences are not genetic; they arise during development and depend on the manner of treatment of the eggs by the queen and the workers, who manipulate such factors as embryonic diet and incubation temperature. The genome of each individual contains all the instructions needed to develop into any one of several 'morphs', but only the genes that form part of one developmental program are activated." ("Phenotypic plasticity," Wikipedia, 26 May 2006).

But then as Keith Stewart Thomson explained, "not all change is evolution" (despite mere words like "the potential `macroevolutionary significance' of `phenotypic plasticity'"):

"Leaping Lizards? All of this makes one sympathetic with Nicholas Wade of The New York Times, who recently wrote an article entitled `Leapin' Evolution Is Found in Lizards.' This was a report on an experiment in which lizards of the species Anolis sagrei from an island in the Bahamas were released onto an island lacking lizards and with a different vegetation pattern (Losos, Warheit and Schoener 1997) [Losos, J.B., Warheit, K.I. & Schoener, T.W.. Adaptive differentiation following experimental island colonization in Anolis lizards. Nature, Vol. 387, 1997, pp.70-73]. After 10 years, the limb proportions of the experimental population had shifted significantly in the direction predicted on the basis of the new host ecology. Whether the results document a case of evolution depends, of course, on definitions. Certainly it is a form of change over time, and such demonstrations are a necessary requirement for documenting a case of Darwinian evolution caught in flagrante delicto. But it is not sufficient to the case. All evolution is change, but not all change is evolution. Rates of change can be measured, as they were in this experiment; to call them `rates of evolution' as do Losos, Warheit and Schoener begs the most interesting question. I would argue that in order to constitute evidence of true evolution a phenomenon must meet three simple criteria: It must be shown to be genetically based, it must be irreversible, and it should result in reproductive isolation of populations. In other words, the smoking gun of evolution is speciation, not local adaptation and differentiation of populations. ... This exciting new study, rather like the superb observational work of Peter and Rosemary Grant on Galapagos finches and a number of other recent studies, at last gives some thorough quantification in a field in which it has been notably lacking. Whether or not they provide the long-sought smoking gun of evolution, the experiments of Losos, Warheit and Schoener have the potential to explore the mechanism(s) underlying the processes of adaptation. Darwin's use of `natural selection' is normally considered to mean the sorting of genetic- based variation within a particular environmental context. The authors of the paper do not use the term. Nor do they consider the short-term directional change observed in these lizards to be evidence for founder effect or genetic drift. Instead, the authors of this exciting Anolis study present it as a possible demonstration of the potential `macroevolutionary significance' of `phenotypic plasticity.' They argue for the `adaptive importance of nongenetic environmental effects on morphological size and shape of animals.' By this they appear to mean that if Anolis can adapt rapidly to new environments without the introduction of new genetic variation, perhaps the mode of rapid evolution required for punctuated equilibrium is a possibility. This less-than-traditional interpretation owes more to the ideas of Waddington (for example, genetic assimilation) or Schmalhausen than to the classical population genetics of Dobzhansky. The million- dollar question is: What mechanisms lie between the short-term, low-scale and wholly reversible results so far obtained and the origin of a new species? What conditions and mechanisms are required to feed back from a given level of phenotypic plasticity to a new genetic or phenotypic constitution? Stay tuned." (Thomson, K.S., "Natural Selection and Evolution's Smoking Gun," American Scientist, Vol. 85, No. 6, November-December 1997, pp.516-518, p.518)

and if these Darwin's finches, like the Bahamas Anolis lizards, are merely another example of phenotypic plasticity, then it would be: 1) mere "change" but not "evolution;" and 2) yet another best example of Darwinian evolution in action (like the Peppered Moth) that would have to be quietly removed from the textbooks.

But in that case it would be even more embarassing for Darwinists because of the link of these finches (i.e. Darwin's finches!) with Darwin and his theory!]

Continued in part #2.

Stephen E. Jones, BSc (Biol).
`Evolution Quotes Book'

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