Continued from part #1.
[Graphic: Gould's three- branched coral model (enhanced by Gert Korthof) of "the basic logic of Darwinian theory" in his, "The Structure of Evolutionary Theory" (p.18). Gould's "paradox of the visibly irrelevant" seems to make a "killing cut" of Darwinism at K3 "scope: extrapolation from micro to macro evolution" and possibly at K2 "efficacy: natural selection as a creative force! Read on.]
Gould drives his "paradox of the visibly irrelevant" point home that, "if we can measure it at all (in a few years), it is too powerful to be the stuff of life's history." Therefore all studies of `evolution in action" like "Trinidad guppy rates" are simply irrelevant to "large-scale evolution" including "from fish to man over more than 400 million years"!:
"Moreover, and with complete generality-the `paradox of the visibly irrelevant' in my title we may say that any change measurable at all over the few years of an ordinary scientific study must be occurring far too rapidly to represent ordinary rates of evolution in the fossil record. The culprit of this paradox, as so often, is the vastness of time (a concept that we can appreciate `in our heads' but seem quite unable to get into the guts of our intuition). The key principle, however ironic, requires such a visceral understanding of earthly time: if evolution is fast enough to be discerned by our instruments in just a few years-that is, substantial enough to stand out as a genuine and directional effect above the random fluctuations of nature's stable variation and our inevitable errors of measurement-then such evolution is far too fast to serve as an atom of steady incrementation in a paleontological trend. Thus, if we can measure it at all (in a few years), it is too powerful to be the stuff of life's history. If large-scale evolution proceeded by stacking Trinidad guppy rates end to end, any evolutionary trend would be completed in a geological moment, not over the many million years actually observed. `Our face from fish to man,' to cite the title of a famous old account of evolution for popular audiences, would run its course within a single geological formation, not over more than 400 million years, as our fossil record demonstrates." (Gould, S.J., "The Paradox of the Visibly Irrelevant," in "The Lying Stones of Marrakech: Penultimate Reflections in Natural History," , Vintage: London, 2001, reprint, p.344. NH p, p.64)
This irrelevancy to "large-scale evolution" of "change measurable at all over the few years of an ordinary scientific study" also includes "stacking ... end to end" the "size and strength of the bill" in "Darwin's finches of the Galapagos Islands":
"Darwin's finches of the Galapagos Islands, where Peter and Rosemary Grant have spent many years documenting fine-scale evolution in size and strength of the bill as rapid climatic changes force an alteration of food preferences" (Gould, 2000, p.336. NH, p.14)!
The fourth (but not last) Gould quote is from his magnum opus where he calls "the paradox of the visibly irrelevant" a "major dilemma" and reiterated that "what we see in our world can't be the direct stuff, by simple extrapolation, of sustained macroevolutionary change":
"Again, we encounter the major dilemma that I call (Gould, 1997f) `the paradox of the visibly irrelevant'-that is, phenomena prominent enough to be detectable and measurable at all in local populations during ordinary human time must cascade to instantaneous completion when scaled into geological time, whereas truly gradual effects in geological time must be effectively invisible at scales of human observation in ecological time. Consequently, what we see in our world can't be the direct stuff, by simple extrapolation, of sustained macroevolutionary change-while what we view as slow and steady in the geological record can't be visible at all (in the same form) by the measuring rod of our own life's duration. ... How can geological gradualism be the extrapolated expression of natural selection within populations? Surely, if a doubling of tooth size (say) requires 2 million years to reach completion, then the process must be providing so small an increment of potential advantage in each generation that natural selection couldn't possibly `see' the effect in terms of reliably enhanced reproductive success on a generational basis. Can a tooth elongated by a tiny fraction of a single millimeter possibly confer any evolutionary advantage in a selective episode during one generation of a population's history? Conversely, if bigger teeth provide such sustained advantages, why stretch the process over millions of years?" (Gould, S.J., "The Structure of Evolutionary Theory," Belknap: Cambridge MA, 2002, Fifth printing, pp.834-835)
Moreover, Gould pointed out that "natural selection within populations" cannot be a significant factor in such "macroevolutionary change" because: 1) "when scaled into geological time the process must be providing so small an increment of potential advantage in each generation that natural selection couldn't possibly `see' the effect"; and 2) "Conversely, if" there was such an advantage, then "why stretch the process over millions of years?"
The last Gould quote is back to his "The Lying Stones of Marrakech" where he notes that: 1) "When lineages do change, their alteration usually occurs `momentarily' in a geological sense," i.e. within "several thousand years"; and 2) "most cases like the Trinidadian guppies and Bahamian lizards" (and "Darwin's finches of the Galapagos Islands") "represent lineages in stasis: (my emphasis):
"When lineages do change, their alteration usually occurs `momentarily' in a geological sense (that is, confined to a single bedding plane) and usually leads to the origin of a new species by branching. Evolutionary rates during these moments may match the observed speed of Trinidadian guppies and Bahamian lizards-for most bedding planes represent several thousand years. But during most of a typical species's lifetime, no change accumulates, and we need to understand why I suspect that most cases like the Trinidadian guppies and Bahamian lizards represent transient and momentary blips and fillips that `flesh out' the rich history of lineages in stasis, not the atoms of substantial and steadily accumulated evolutionary trends. Stasis is a dynamic phenomenon. Small local populations and parts of lineages make short and temporary forays of transient adaptation, but these tiny units almost always die out or get reintegrated into the general pool of the species. (Losos himself regards the new island populations of lizards as evolutionarily transient in exactly this sense-for such tiny and temporary colonies are almost always extirpated by hurricanes in the long run. How, then, can such populations represent atoms of a major evolutionary trend?" (Gould, 2000, pp.344-345)
As evolutionary biologist Mark Pagel, in reviewing Gould's fellow punctuationist Niles Eldredge's book, ironically called "The Pattern of Evolution" noted, "Palaeobiologists instead of finding the slow, smooth and progressive changes Darwin had expected, they saw in the fossil records patterns hauntingly reminiscent of creation" (my emphasis)!:
"Palaeobiologists flocked to these scientific visions of a world in a constant state of flux and admixture. But instead of finding the slow, smooth and progressive changes Lyell and Darwin had expected, they saw in the fossil records rapid bursts of change, new species appearing seemingly out of nowhere and then remaining unchanged for millions of years-patterns hauntingly reminiscent of creation." (Pagel, M., "Happy accidents?" Review of "The Pattern of Evolution," by Niles Eldredge, W.H. Freeman, 1999. Nature, Vol. 25 February 1999, pp.664-665, p.665).
Maybe that is because it was creation!
Stephen E. Jones, BSc (Biol).
`Evolution Quotes Book'
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