Evolution Encyclopedia Vol. 2
Chapter 17 Appendix Part 2
7- THE CAMBRIAN AND PRECAMBRIAN PROBLEM
The Cambrian-Precambrian explosion, the fossil gap problem, the abrupt appearance problem, end the lack of transitional forms are dealt with in this and the next three appendix sections. Together (or singly), these four fossil facts annihilate evolutionary theory.
The Cambrian is the bottom strata level containing fossils. Below that is the Precambrian which is practically devoid of fossils. In the Cambrian there are unimagined trillions upon trillions of fossils; below it in the Precambrian there is next to nothing of them. That is the problem in brief: immense numbers of fullyformed, complex fossilized creatures, and just below them a paucity that amounts to practically nothing.
"Chief puzzle . . no record . . entire first part . . missing."
"The chief puzzle in the record of life's history on earth: the sudden appearance, some 600 million years ago, of most basic divisions of the plant and animal kind. There is virtually no record of how these divisions came about. Thus the entire first part of evolutionary history is missing." —*New York Times, October 25, 1964, p. 8E.
"No trace."
"The fossil record contains no trace of these preliminary stages in the development of many-celled organisms." —*Robert Jastrow, Red Giants and White Dwarfs (1979), p. 249.
"Rocks below a certain level . . devoid of fossils."
"One feature of the fossil record that puzzled 19th century geologists was the rocks below a certain level seemed to be devoid of fossils of animal or plats remains. The lowest obviously fossil-bearing deposits, which the geologists first identified in Wales, they assigned to the Cambrian period . . [It was clearly seen way back then that] living things were well established by the beginning of the Cambrian." —*Chris Peat and *Will Diver, "First Signs of Life on Earth," in New Scientist, September 18, 1983, pp. 776-781.
"Suddenly appear. . can give no satisfactory answer . . the difficulty . . is very great."
"There is another and allied difficulty, which is much more serious. I allude to the manner in which species belonging to several of the main divisions of the animal kingdom suddenly appear in the lowest known fossiliferous rocks . .
"If the [evolution] theory be true, it is indisputable that, before the lowest Cambrian stratum was deposited, long periods elapsed, as long as, or probably far longer than, the whole interval from the Cambrian age to the—present day; and that during these vast periods the works swarmed with living creatures . .
"To the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system, I can give no satisfactory answer . . the difficulty of assigning any good reason for the absence of vast piles of strata rich in fossils beneath the Cambrian system is very great." —*Charles Darwin, The Origin of Species, pp. 359-361(1909 Harvard Classics edition). "A fatal objection."
"The abrupt manner in which whole groups of species suddenly appear in certain formations, has been urged by several paleontologists—for instance, by Agassiz, Pidet, and Sedgwick—as a fatal objection to the belief in the transmutation of species. If numerous species, belonging to the same genera a families have really started into life at once, the fact would be fatal to the theory of evolution through natural selection." —*Charles Darwin, Origin of the Species, p. 344 (different edition than preceding quotation).
"As inexplicable '. . as it was to Darwin."
"Granted an evolutionary origin of the main groups of animals, and not an act of special creation, the absence of any record whatsoever of a single member of any of the phyla in the Precambrian rocks remains as inexplicable on orthodox grounds as it was to Darwin." —*T. Neville George, "Fossils in Evolutionary Perspective, Science Progress, January 1960, p. 5 (Glasgow University geology professor).
"Sudden appearance and.. remarkable composition [large numbers and varieties] . . puzzle of this sudden proliferation. . complex organisms . . of nearly every major phylum."
"Both the sudden appearance and the remarkable composition of the animal life characteristic of Cambrian times are sometimes explained away a overlooked by biologists. Yet recent paleontological research has made the puzzle of this sudden proliferation of living organisms increasingly difficult for anyone to evade . .
"These animals were neither primitive nor generalized in anatomy: they were complex organisms that clearly belonged to the various distinct phyla, or major groups of animals, now classified as metazoan. In fact, they are now known to include representatives of nearly every major phylum that possessed skeletal structures capable of fossilization; . .
"Yet before the Lower Cambrian there is scarcely a trace of them. The appearance of the Lower Cambrian fauna . . can reasonably be called a 'sudden' event.
"One can no longer dismiss this event by assuming that all Pre-Cambrian rocks have been too greatly altered by time to allow the fossils ancestral to the Cambrian metazoans to be preserved. . even if all the Pre-Cambrian ancestors of the Cambrian metazoans were similarly softbodied and therefore rarely preserved, far more abundant traces of their activities should have been found in the Pre-Cambrian strata than has proved to be the case. Neither can the general failure to find Pre-Cambrian animal fossils be charged to any lack of trying." —*Scientific American, August 1964, pp. 34-36.
"Abundant representation . . numerous and varied . . but [earlier] almost barren of . . life . . no satisfactory answer."
"From the beginning of the Cambrian up through the rest of the geological sequence, we have an abundant representation of animal life at every stage; even in Lower Cambrian formations, marine invertebrates are numerous and varied. Below this, there are vast thicknesses of sediments in which the progenitors of the Cambrian forms should be expected. But we do not find them; these older beds are almost barren of evidence of life, and the general picture could reasonably be said to be consistent with the idea of a special creation at the beginning of Cambrian times.
" 'To the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system,' said Darwin, 'I can give no satisfactory answer.' Nor can we today." —*Alfred Romer, "Darwin and the Fossil Record, " in Natural History, October 1959, pp. 466-467.
"Below. . almost no skeletal fossils, only traces. . rampant proliferation of life forms [above]."
"Below the [Cambrian] boundary there are almost no skeletal fossils, only traces where softbodied, multicellular animals, or metazoans, burrowed or left imprints in sediments as old as 1150 million years or older . . With the appearance of . . the Cambrian period and the familiar fossil began . . Within a few tens of millions of years . . nearly all major forms of life known today had appeared in the fossil record. This rampant proliferation of life forms is called the 'Cambrian Explosion.' " —*Chryl Simon, "in with the Older," in Science News, May 7, 1983, pp. 300-301.
"The absence . . is puzzling."
"If there has bean evolution of life, the absence of the requisite fossils in the rocks older than the Cambrian is puzzling." —*Marshall Kay and Edwin M. Colbert, Stratigraphy and life History (1965), p. 103.
"No fossils of complex organisms."
"Geologists have discovered many unaltered Precambrian sediments,— and they contain no fossils of complex organisms." —*Salvador E Luria, *Stephen Jay Gould, and *Sam Singer, A View of Life (1981), p. 651.
"We did not find a series of fossils covering the gradual changes . . [instead] developed species suddenly appeared."
"The creation account in Genesis and the theory of evolution could not be reconciled. One must be right and the other wrong. The story of the fossils agreed with the account of Genesis. In the oldest rocks we did not find a series of fossils covering the gradual changes from the most primitive creatures to developed forms, but rather in the oldest rocks, developed species suddenly appeared. Between every species there was a complete absence of intermediate fossils." —D.B. Gower, "Scientist Rejects Evolution," Kentish Times, England, December 11, 1975, p. 4.
"Do not reveal a simple beginning."
"The problem for biology is to reach a simple beginning. Fossil residues of ancient life-forms discovered in the rocks do not reveal a simple beginning . . so the evolutionary theory lacks a proper foundation." —*Fred Hoyle and *Chandra Wickramasinghe, Evolution From Space (1981), p. 8.
"Ancestors of these full-blown living creatures . . should be found."
"If progressive evolution from simple to complex is correct, the ancestors of these full-blown living creatures in the Cambrian should be found; but they have not been found and scientists admit there is little prospect of their ever being found. On the basis of the facts alone, on the basis of what is actually found in the earth, the theory of a sudden creative act in which the major forms of life were established fits best." —Harold G. Coffin, "Evolution or Creation?" Liberty, September-October 1975, p. 12.
"One of the major unsolved problems."
"One of the major unsolved problems of geology and evolution is the occurrence of diversified, multi-called marine invertebrates in the lower Cambrian rocks on all the continents and their absence in rocks of greater age." —*D. Axelrod, Science, 128.7, 1958.
"[Precambrian] sediments were suitable for the preservation of fossils."
"However when we turn to examine the Precambrian rocks for forerunners of these early Cambrian fossils, they are nowhere 1o be found. Many thick (over 5,000 feet) sections of sedimentary rock are now known to lie in unbroken succession below strata containing the earliest Cambrian fossils. These sediments apparently were suitable for the preservation of fossils because they are often identical with overlying rocks which are fossiliferous, yet no fossils are found in them." —*D. Axelrod, Science, Vol. 128, No. 7, 1958.
"Abrupt manner. . fatal objection . . suddenly appear."
"The abrupt manner in which whole groups of species suddenly appear in certain formations has been urged by several paleontologists . . as a fatal objection to the belief in the transmutation of species. There is another and allied difficulty, which is much more serious. I allude to the manner in which species belonging to several of the main divisions of the animal kingdom suddenly appear in the lowest known fossiliferous rocks. . To the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system I can give no satisfactory answer. . The case at present must remain inexplicable; and may be truly urged as a valid argument against the [evolutionary] views here entertained." —*Charles Darwin, The Origin of Species, Part Two (1902 ad.), pp. 83, 88, 91, 92.
"No new phyla have emerged since the Cambrian . . Since then evolution has been restricted to working within about a dozen different patterns."
Back in the 'thirties, the eminent physicist Professes J.D. Bernal advanced the idea that evolution was steadily accelerating. It took about a billion years for the first life forma, such as bacteria, to appear, about half a billion more to produce the filamentous algae, and as much again to produce the eukaryotes a nucleated cells. The first fish appeared 500 million years ago, the first reptiles, 300 million years ago, the first mammals, 200 million years ago. Thus the intervals shortened.
"But to say evolution is accelerating means, presumably, not just that the really major changes occurred at shorter intervals but also that novel forms within large groups were appearing increasingly frequently.
"However, exactly the contrary may be true.
"In contrast with Bernal, Professor C.D. Darlington, Sheridan Professor of Botany at Oxford and one time directs of the John Innes Horticultural Institute, considers that evolution is slowing down. He points out that the primitive organisms known as prokaryotes evolved early and then settled down: they do not seem to have changed appreciably in the last billion years. Professor Grasse is another who thinks evolution is slowing down or even coming to a stop. So is Professor James Brough, Professor of Zoology at Cardiff University. He points out that no new phyla have emerged since the Cambrian age, 500 million years ago. Since then evolution has been restricted to working within about a dozen different patterns. Moreover, the emergence of new classes within phyla had ceased by the Lower Paleozoic, around 400 million years ago. When we descend to the next taxonomic category, the orders, we find that of forty-seven known fossil orders forty had evolved by that time; in the next fifty million years (the Devonian) only three more appeared; and in the the next 170 million (the whole Mesozoic) only four, since when none have. There has also been a marked slowing down, Brough holds. in the production of new families. 'As to the future,' he concludes ominously, 'evolution may go on waking in smaller and smaller fields until it ceases altogether.'
"These are fighting words of course, for the orthodox geneticist assumes that the rate of mutation stays constant unless it can be shown that some unusual environmental effect has increased it." —*G.R. Taylor, Great Evolution Mystery (1983), pp. 80-81.
"The first billion years . . are blank pages."
"Sometime in the first billion years, life appeared on the earth's surface. Slowly, the fossil record indicates, living organisms climbed the ladder from simple to more advanced forms... The critical first billion years, during which life began are blank pages in the earth's history." —*Robert Jastrow, Red Giants and White Dwarfs (1979), P. 97.
"No trace of these prelimary stages."
"The fossil record contains no trace of these preliminary stages in the development of manycelled organisms." —*Robert Jasbow, Red Giants and White Dwarfs (1979), p. 249.
"Initial steps . . are not known . . no trace remains."
"The initial steps.. are not known; . . no trace of them remains." —*Robert Jastrow, Red Giants end White Dwarfs (1979), p. 224.
"Three-quarters of the book [is] blank."
"For at least three-quarters of the book of ages engraved in the earth's crust the pages are blank." —*Lincoln Barnett, The World We Live In (1955), p. 93.
"Suddenly appeared . . nearly all . . major groups."
"During the Cambrian Period there suddenly appeared representatives of nearly all the major groups of animals now recognized. It was as if a giant curtain has been lifted to reveal a works teeming with life in fantastic diversity. The Cambrian "curtain" has become the touchstone of the creation theory. Darwin was aware of the problem this created for evolutionists, and it remains a problem today. Evolutionists keep hoping that new discoveries will eventually fill in the missing pieces of the fossil puzzle, but the change of success may be less than those of finding the proverbial "needle in the haystack." —*Stanfield, The Science of Evolution (1977), p. 76.
"Why should such complex organic forms . . be absent . . in the . . preceding years?"
"[The lack of Pre-Cambrian fossils is] one of the major unsolved problems of geology and evolution. Why should such complex organic forms be in rocks about 600 million years old and be absent or unrecognized in the records of the preceding two billion years? . . If there has been evolution of life, the absence of the requisite fossils in the rocks older than Cambrian is puzzling." —*Daniel Axelrod, quoted in *Marshall Kay and *Edwin H. Colbert, Stratigraphy and Life History, p. 102.
"Perennial puzzle.. organisms of.. complexity arose rapidly."
"The abrupt appearance of higher taro in the fossil record has been a perennial puzzle . . If we read the record rather literally, it implies that organisms of new grades d complexity arose and radiated relatively rapidly." —*James W. Valentine and Cathryn A. Campbell, "Genetic Regulation and the Fossil Record, " American Scientist, November-December, 1975, p. 873.
"Precambrian [is] . . devoid of any recognizable geologic time significance."
"The more than amply proved and almost unanimously recognized impossibility of establishing any practically useful broadly regional or world-wide geologic time scale based on the physical-stratigraphic criteria alone for the vast expanse of pre-Cambrian time supplies conducive proof that these phenomena are devoid of any generally recognizable geologic time significance." —*J. A. Jeletzky, "Paleontology: Basis of Practical Geochronology," in Bulletin of the American Association of Petroleum Geologists, April 1956, p. 884.
"The most important missing link of all . . [is] nine-tenths of the chain."
"Most paleontologists today give little thought to fossiliferous rocks older than the Cambrian, thus ignoring the most important missing link of all. Indeed the missing Pre-Cambrian record cannot properly be described as a link for it is in reality, about nine-tenths of the chain d life: the first nine-tenths." —*H. S. Ladd, "Introduction," in Treatise on Marine Ecology and Paleoecology, Vol. 2, Geological Society of America Memoir, 67 (1957), p. 7.
"Then there was something of an explosion . . sudden development where, just before, there was none."
"Then there was something of an explosion. Beginning about six hundred million years ago, and continuing for about ten to fifteen million years, the earliest known representatives of the major kinds of animals still populating today's seas made a rather abrupt appearance. This rather protracted 'event' shows up graphically in the rock record: all over the world, at roughly the same time, thick sequences of rocks, barren of any easily detected fossils, are overlain by sediments containing a gorgeous array of shelly invertebrates: trilobites (extinct relatives of crabs and insects), brachiopods, mollusks. All of the typical forma of hard-shelled animals we see in the modern oceans appeared, albeit in primitive, prototypical form, in the seas of six hundred million years ago.
"Creationists have made much of this sudden development of a rich and varied fossil record where, just before, there was none . .
"Indeed, the sudden appearance of a varied, well-preserved array of fossils, which geologists have used to mark the beginnings of the Cambrian Period (the oldest division of the Paleoxpic Era) does pose a fascinating intellectual challenge." —*N. Eldredge, The Monkey Business: A Scientist Looks at Creationism (1982), p. 44.
"A century of intensive search . . has thrown . . little light on [the] problem."
"A century of intensive search for fossils in the pre-Cambrian rocks has thrown very little light on this problem. Early theories that those rocks were dominantly nonmarine or that once contained fossils have been destroyed by heat and pressure have been abandoned because the pre-Cambrian rocks of many districts physically are very similar to younger rocks in all respects except that they rarely contain any records whatsoever of past life." –*Norman D. Newell, "The Nature of the Fossil Record, " in Proceedings of the American Philosophical Society (1959), Vol. 2, pp. 284-285.
"Animals of . . earliest fauna. . similar to. . animals of present period."
"Strange as it may seem, the animals of the very earliest fauna of which our knowledge is sufficient to enable us to speak with confidence, the fauna of the Cambrian period, were singularly similar to the animals of the present day. In the Cambrian crustaceans were crustaceans, echinoderms were echinoderms, arrow-worms were arrow-worms, and mollusks were mollusks just as unmistakably as they are now." —*Austin H. Clark, The New Evolution: Zoogenesis (1930), p. 101.
"One of the major unsolved problems of geology."
"One of the major unsolved problems of geology and evolution is the occurrence of diversified, multicellular marine invertebrates in Lower Cambrian rocks on all the continents and their absence in rocks of greater age . . These sediments apparently were suitable for the preservation of fossils, because they often are identical with overlying rocks which are fossiliferous, yet no fossils are found in them." —"Daniel I. Axelrod, "Early Cambrian Marine Fauna," in Science, July 4, 1958, p. 7.
"Most puzzling feature . . [and] greatest inadequacy."
"The sudden appearance of life is not only the most puzzling feature of the whole fossil record but also its greatest apparent inadequacy." —*George Gaylord Simpson, "The History of Life," in Sol Tax (ed.), Evolution of Life, p. 144.
"Vast stretches of little or no change and one evolutionary burst that created the whole system."
"Increasing diversity and multiple transitions seem to reflect a determined and inexorable progression toward higher things. But the paleontological record supports no such interpretation. There has been no steady progress in the higher development of organic design. We. have had, instead, vast stretches of little or no change and one evolutionary burst that created the whole system." —*Steven Gould, "Paleontology and the Modern Synthesis," in Evolutionary Synthesis (1980), p. 164.
"Sudden, widespread appearance of numerous types. . has puzzled paleontologists for more than a century."
"The beginning of the Phanerozoic Aeon of earth history, about 600 million years ago, is marked in the fossil record by the sudden, widespread appearance of numerous types of invertebrate animals and macroscopic algae. This 'explosion' of advanced life forms, an event that apparently occurred within a period of only ten or twenty million years, has puzzled paleontologists for more than a century.
"In Charles Darwin's day, for example, when the Precambrian was thought to be entirely devoid of fossils, this abrupt beginning of the fossil record presented a major dilemma, a problem that Darwin thought would require convincing explanation if his theory of evolution were to be ultimately accepted." —*J. Schopf, "The Age of Microscopic Life," in Endeavor 34 (19 75), p. 57.
"Began with the greatest of geological bangs—the Cambrian explosion . . nearly all major groups . . made their first appearance."
"About 570 million years ago, our modern fossil record began with the greatest of geological bangs—the Cambrian explosion. Within a few million years, nearly all major groups of invertebrates with hard parts made their first appearance in the fossil record." —*Stephen Gould, "The Ediacaran Experiment, " in Natural History, February 1984, p. 14.
"Still great gaps in the fossil record."
"There are still great gaps in the fossil record. Most of the major groups of animals (phyla) appear fully fledged in the early Cambrian rocks, and we know of no fossil forms linking them." —*Colin Patterson, in Evolution (1978), p. 133.
"Confronted with the abrupt appearance."
"When confronted with the abrupt appearance of many new families of a higher taxon, some workers have sought an explanation in the imperfection of the fossil record. The most general problem to which this approach has been taken is the apparently sudden appearance in the fossil record of the diverse classes of invertebrates that characterize the Cambrian system. In fact, it was Darwin, the first worker seriously faced with the 'Cambrian problem,' who . . wrote in `On the Origin of Species" The case at present must remain inexplicable; and may be truly urged as a valid argument against the views [evolution by natural selection) here entertained'." —*S. Stanley, in Macroevolution (1979), p. 67.
"Lower four-fifths . . is lifeless.. [then] promptly most of the types we . . know."
"The lower four-fifths of the rock of the earth's crust is lifeless. Then life suddenly appears and is at once general across the earth, and promptly demonstrates most of the types we now know. This is not the evidence the evolutionist wants, and is quite fatal to his claims. This is Creation." — E. Shute, in Flaws in the Theory of Evolution (1961), p. 5.
"Complex life did arise with startling speed . . largely fruitless century trying to explain."
"The Precambrian fossil record is little more (save at its very end) than 2.5 billion years of bacteria and blue-green algae. Complex life did [instead] arise with startling speed near the base of the Cambrian . . Paleontologists have spent a largely fruitless century trying to explain this Cambrian 'explosion'—the steep rise in diversity during the first 10 to 20 million years of the Cambrian period . .
"All paleontologists know that the fossil record contains precious little in the way of intermediate forms; transitions between major groups are characteristically abrupt." —*Stanley J. Gould, in Natural History, Vol. 86, No. 6 (1977).
"The object of considerable research and speculation and numerous hypotheses."
"One of the most striking and enigmatic aspects of paleontology has been the sudden appearance of advanced and diversified metazoan organisms in the early Cambrian. This subject has been the object of considerable research and speculation and numerous hypotheses have been proposed to explain the phenomenon." —*K. M. Towe, "Oxygen-Collagen Priority and the Early Metazoan Fossil Record," in Proceedings of the National Academy of Science, 65(4)781 (1970).
"Plants.. similar to modern plants.. [in] Cambrian."
"Traces of plants quite similar to modern plants are found, and have been found for years, in rocks called as old as Cambrian. I have come upon a reference which shows that this is not a very recent discovery. Berry, writing in 1927, mentioned coal, or metamorphosed coal, indicating plants of some complexity, underlying the Gogebic in Wisconsin, and in the Sudburyian series at Chelmsford, Ontario. He seemed to consider them pre-Cambrian. Later, in response to criticism, he reiterated his findings, and urged that ‘ . . we are forced to believe in a pre-Cambrian terrestrial flora of relatively high organization.'" —*Panorama of Science," in Creation Research Society Quarterly, June 1977, p. 70. [Quotation from *E. W. Berry, "Terrestrial Floras in the Pre-Cambrian," in American Journal of Science, 15 (89):431. j
"The entire system of life arose during about 10 percent of its history."
"Furthermore, consider the `Cambrian explosion,' i.e., the sudden appearance of a great diversity of life forms in the Cambrian without signs of many precursors, when 'the entire system of life arose during about 10 percent of its history surrounding the Cambrian explosion some 600 million years ago.’ [Stephen Jay Gould, Ever Since Darwin (1980)] Gould successfully demolishes one attempt after another to explain this phenomenon." —Christopher Bluth, "Creationism Defended, " in Creation Research Society Quarterly, June 1983, p. 20.
"Most of the biochemical complexity of life [at the very beginning]."
"Most of the biochemical complexity of life was present already at the time the oldest surface rocks of the Earth were formed." —*Fred Hoyle and *Chandra Wickramasinghe, Evolution from Space (1981), dust jacket.
"All existing phyla except the chordate [at the very beginning]."
"The animals and plants of the oldest geological strata represent all existing phyla except the chordate." —*H.H. Newmann, Evolution, Genetics and Eugenics. [Note: More recently, fish in chordate phylum have been found in the Cambrian.]
"More than half their evolution."
"Most of the invertebrate phyla had already undergone more than half their evolution at the time when the earliest fossil remains were deposited." —*H.H. Newmann, Evolution, Genetics and Eugenics. [Note: no evolution after the Cambrian either, for no transitional forms found, only complete species.]
"The difficulty. . is very great . . must remain inexplicable."
"To the question why we do not find rich fossiliferous deposits belonging to these assumed earliest periods prior to the Cambrian system, I can give no satisfactory answer.
"Nevertheless, the difficulty of assigning any good reason for the absence of vast piles of strata rich in fossils beneath the Cambrian system is very great.
"The case at present must remain inexplicable; and may be truly urged as a valid argument against the views here entertained.
"The abrupt manner in which whole groups of species suddenly appear in certain formations, has been urged by several paleontologists—for instance, by Agassiz, Pictet, and Sedgwick—as a fatal objection to the belief in the transmutation of species. If numerous species belonging to the same genera or families, have really started into life at once, the fact would be fatal to the theory of evolution through natural selection. For the development by this means of a group of forms, all of which are descendants from some one progenitor, must have been an extremely slow process; and the progenitors must have lived long before their modified descendants." —I. L. Cohen, Darwin Was Wrong —A Study in Probabilities (1984), p. 89-90.
"One of the greatest enigmas."
"One of the greatest enigmas in paleontology is the relatively abrupt appearance of hard skeletal parts in the fossil record near the beginning of the Cambrian." —*Simon Conway Morris, "Search for the Precambrian-Cambrian Boundary," in American Scientist, 75:157 (1987).
"Established virtually all the major animal body forms."
"Described recently as 'the most important evolutionary event during the entire history of the Metazoa,' the Cambrian explosion established virtually all the major animal body forms—Bauplane or phyla—that would exist thereafter, including many that were quickly 'weeded out' and became extinct. Compared with the 30 or so extant phyla [present today], some people estimate that the Cambrian explosion may have generated as many as 100." —*Roger Lewin, "A Lopsided Look at Evolution," in Science, 241:201 (1988).
"[The earliest creatures] must have lived long before the Cambrian."
"Most of the arguments which have convinced me that all the existing species of the same group are descended from a single progenitor, apply with equal force to the earliest known species. For instance, it cannot be doubted that all the Cambrian and Silurian trilobites are descended from some one crustacean, which must have lived long before the Cambrian age, and which probably differed greatly from any known animal." —I. L Cohen, Darwin Was Wrong—A Study in Probabilities (1984), p. 90.
"The puzzle of this sudden proliferation."
"Both the sudden appearance and the remarkable characteristic of Cambrian ties are sometimes explained away or overlooked by biologists. Yet recent paleontological research has made the puzzle of this sudden proliferation of living organisms increasingly difficult for anyone to evade . . Neither can the general failure to find Precambrian animal foils be charged to any lack of trying." —*Lincoln Barnett and the *Editors of Time-Life, The World We Live In (1955), p. 93.
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