"The history of most fossil species includes two features particularly inconsistent with gradualism: 1. Stasis. Most species exhibit no directional change during their tenure on earth. They appear in the fossil record looking much the same as when they disappear; morphological change is usually limited and directionless. 2. Sudden appearance. In any local area, a species does not arise gradually by the steady transformation of its ancestors; it appears all at once and `fully formed.'" (Gould, Stephen J. [Professor of Zoology and Geology, Harvard University, USA], "Evolution's Erratic Pace," Natural History, Vol. 86, No. 5, May 1977, p.14).
[top]"Paleontologists had long been aware of a seeming contradiction between Darwin's postulate of gradualism, confirmed by the work of population genetics, and the actual findings of paleontology. Following phyletic lines through time seemed to reveal only minimal gradual changes but no clear evidence for any change of a species into a different genus or for the gradual origin of an evolutionary novelty. Anything truly novel always seemed to appear quite abruptly in the fossil record." (Mayr, Ernst [Emeritus Professor of Zoology, Harvard University], "Toward a New Philosophy of Biology: Observations of an Evolutionist," Harvard University Press: Cambridge MA, 1988, pp.529-530).
[top]"No wonder paleontologists shied away from evolution for so long. It seems never to happen. Assiduous collecting up cliff faces yields zigzags, minor oscillations, and the very occasional slight accumulation of changeover millions of years, at a rate too slow to really account for all the prodigious change that has occurred in evolutionary history. When we do see the introduction of evolutionary novelty, it usually shows up with a bang, and often with no firm evidence that the organisms did not evolve elsewhere! Evolution cannot forever be going on someplace else. Yet that's how the fossil record has struck many a forlorn paleontologist looking to learn something about evolution." (Eldredge, Niles [Chairman and Curator of Invertebrates, American Museum of Natural History], "Reinventing Darwin: The Great Evolutionary Debate," [1995], p.hoenix: London, 1996, p.95).
[top]"The facts of greatest general importance are the following. When a new phylum, class, or order appears, there follows a quick, explosive (in terms of geological time) diversification so that practically all orders or families known appear suddenly and without any apparent transitions. Afterwards, a slow evolution follows; this frequently has the appearance of a gradual change, step by step, though down to the generic level abrupt major steps without transitions occur. At the end of such a series, a kind of evolutionary running- wild frequently is observed. Giant forms appear, and odd or pathological types of different kinds precede the extinction of such a line. Moreover, within the slowly evolving series, like the famous horse series, the decisive steps are abrupt, without transition: for example, the choice of the middle finger for further transformation, as opposed to the two middle fingers, in the evolution of the artiodactyls; or the sudden transition from the four-toed to the three-toed foot with predominance of the third ray." (Goldschmidt, Richard B., [late Professor of Genetics, University of California, Berkeley], "Evolution, as Viewed by One Geneticist," American Scientist, Vol. 40, January 1952, p.97).
[top]"Zircon dating, which calculates a fossil's age by measuring the relative amounts of uranium and lead within the crystals, had been whittling away at the Cambrian for some time. By 1990, for example, new dates obtained from early Cambrian sites around the world were telescoping the start of biology's Big Bang from 600 million years ago to less than 560 million years ago. Now, with information based on the lead content of zircons from Siberia, virtually everyone agrees that the Cambrian started almost exactly 543 million years ago and, even more startling, that all but one of the phyla in the fossil record appeared within the first 5 million to 10 million years."We now know how fast fast is," grins Bowring. "And what I like to ask my biologist friends is, How fast can evolution get before they start feeling uncomfortable?" (Nash, J. Madeleine [journalist], "When Life Exploded," Time, December 4, 1995, p74. http://www.time.com/time/magazine/archive/1995/951204/cover.html). * This sole exception was "Bryozoa, a group of sessile and colonial marine organisms, [which] do not arise until the beginning of the subsequent, Ordovician period, but this apparent delay may be an artifact of failure to discover Cambrian representatives." (Gould, Stephen J. [Professor of Zoology and Geology, Harvard University, USA], "The Evolution of Life on the Earth," Scientific American, Vol. 271, No. 4, October 1994, p.67)
[top]"The rapid development as far as we can judge of all the higher plants within recent geological times is an abominable mystery." (Darwin, Charles R., [English naturalist and founder of the modern theory of evolution], letter to J.D. Hooker, July 22nd 1879, in Darwin F. & Seward A.C., eds., "More Letters of Charles Darwin: A Record of His Work in a Series of Hitherto Unpublished Papers," John Murray: London, 1903, Vol. II, pp.20-21).
[top]"The history of most fossil species includes two features particularly inconsistent with gradualism: 1. Stasis. Most species exhibit no directional change during their tenure on earth. They appear in the fossil record looking much the same as when they disappear; morphological change is usually limited and directionless. 2. Sudden appearance. In any local area, a species does not arise gradually by the steady transformation of its ancestors; it appears all at once and `fully formed.'" (Gould, Stephen J. [Professor of Zoology and Geology, Harvard University, USA], "Evolution's Erratic Pace," Natural History, Vol. 86, No. 5, May 1977, p.14).
[top]"For millions of years species remain unchanged in the fossil record," said Stephen Jay Gould, of Harvard, "and they then abruptly disappear, to be replaced by something that is substantially different but clearly related." (Lewin, Roger [biochemist, former editor of New Scientist and science writer], "Evolutionary- Theory Under Fire: An historic conference in Chicago challenges the four-decade long dominance of the Modern Synthesis," Science, Vol. 210, 21 November 1980, p.883).
[top]"At the core of punctuated equilibria lies an empirical observation: once evolved, species tend to remain remarkably stable, recognizable entities for millions of years. The observation is by no means new, nearly every paleontologist who reviewed Darwin's Origin of Species pointed to his evasion of this salient feature of the fossil record. But stasis was conveniently dropped as a feature of life's history to he reckoned with in evolutionary biology. And stasis had continued to be ignored until Gould and I showed that such stability is a real aspect of life's history which must be confronted-and that, in fact, it posed no fundamental threat to the basic notion of evolution itself. For that was Darwin's problem: to establish the plausibility of the very idea of evolution, Darwin felt that he had to undermine the older (and ultimately biblically based) doctrine of species fixity. Stasis, to Darwin, was an ugly inconvenience." (Eldredge, Niles [Chairman and Curator of Invertebrates, American Museum of Natural History], "Time Frames: The Rethinking of Darwinian Evolution and the Theory of Punctuated Equilibria," Simon & Schuster: New York NY, 1985, pp.188-189).
[top]"The principal problem is morphological stasis. A theory is only as good as its predictions, and conventional neo-Darwinism, which claims to be a comprehensive explanation of evolutionary process, has failed to predict the widespread long-term morphological stasis now recognized as one of the most striking aspects of the fossil record." (Williamson, Peter G. [Assistant Professor of Geology, Harvard University], "Morphological stasis and developmental constraint: real problems for neo-Darwinism," Nature, Vol. 294, 19 November 1981, p.214).
[top]"The bony-finned coelacanth, thought to be long extinct but rediscovered in 1938, has been approximately static some 450 million years (Avers 1989, 317). ... The nearly timeless species are not exempt from the changes of proteins that go on in all living beings, and they could surely vary in many ways without loss of adaptiveness, but their patterns have become somehow frozen. ... From the point of view of conventional evolutionary theory long-term stasis is hard to explain. Rapid evolution is comprehensive as species adapt to new conditions or opportunities but it is incongruous that species remain unchanged through changing conditions over many million years (Sheldon 1990, 114)." (Wesson, Robert G. [political scientist], "Beyond Natural Selection," [1991], MIT Press: Cambridge MA, 1994, reprint, pp.207-208).
[top]"So, we have stasis. What are we to make of it? How do we explain it? Some of us would say that the lineage leading to Latimeria [Coelacanth] stood still because natural selection did not move it. In a sense it had no 'need' to evolve because these animals had found a successful way of life deep in the sea where conditions did not change much. Perhaps they never participated in any arms races. Their cousins that emerged onto the land did evolve because natural selection, under a variety of hostile conditions including arms races, forced them to. Other biologists, including some of those that call themselves punctuationists, might say that the lineage leading to modern Latimeria actively resisted change, in spite of what natural selection pressures there might have been. Who is right? In the particular case of Latimeria it is hard to know . ... Let us, to be fair, stop thinking in terms of Latimeria in particular. It is a striking example but a very extreme one ... It is conceivable that coelacanths stopped evolving because they stopped mutating perhaps because they were protected from cosmic rays at the bottom of the sea! - but nobody, as far as I know, has seriously suggested this ... " (Dawkins, Richard [zoologist and Professor for the Public Understanding of Science, Oxford University], "The Blind Watchmaker," [1986], Penguin: London, 1991, reprint, pp.246,247).
[top]* Authors with an asterisk against their name are believed not to be evolutonists.
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