Evolution: a Theory in Crisis By: Michael Denton
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╝ Evolution: A Theory in Crisis By: Michael Denton ]1[ Preface It is not hard to understand why the question of evolution should attract such attention. The idea has come to touch every aspect of modem thought; and no other theory in recent times has done more to mould the way we view ourselves and our relationship to the world around us. The acceptance of the idea one hundred years ago initiated an intellectual revolution more significant and far reaching than even the Copernican and Newtonian revolutions in the sixteenth and seventeenth centuries. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p15.] The triumph of evolution meant the end of the traditional belief in the world as a purposeful created order - the so-called teleological outlook which had been predominant in the western world for two millennia. According to Darwin, all the design, order and complexity of life and the eerie purposefulness of living systems were the result of a simple blind random process - natural selection. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p15.] Any suggestion that there might be something seriously wrong with the Darwinian view of nature is bound to excite public attention, for if biologists cannot substantiate the fundamental claims of Darwinism, upon which rests so much of the fabric of twentieth century thought, then clearly the inte1lectual and philosophical implications are immense. Small wonder, then, that the current tumult in biology is arousing such widespread interest. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p16.] In this book I have adopted the radical approach. By presenting a systematic critique of the current Darwinian model, ranging from paleontology to molecular biology, I have tried to show why I believe that the problems are too severe and too intractable to offer any hope of resolution in terms of the orthodox Darwinian framework, and that consequently the conservative view is no longer tenable. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p16.] 1 Genesis Rejected Biology in the early decades of the nineteenth century was dominated by the ]2[ idea that the organic world was a fundamentally discontinuous system in which all the major groups of organisms were unique and isolated and unlinked by transitional forms. Species were held to breed true to type, generation after generation, without ever undergoing any significant sort of change. Where there was variation, it was only trivial variation within the clearly defined limits of the species or type. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p17, 18.] As William Coleman, an authority on Georges Cuvier, points out:1 The organism, being a functionally integrated whole each part of which stood in close relation to every other part, could not, under pain of almost immediate extinction, depart significantly from the norms established for the species by the first anatomical rule. A major change, for example, a sharp increase in the heart beat or the diminution by half of the kidney and thus a reduction in renal secretion, would by itself have wrought havoc with the general constitution of the animal. In order that an animal might persist after a change of this magnitude it would be necessary that the other organs of the body be also proportionally modified. In other words, an organism much change en bloc or not at all. Only salutatory modification could occur, and this idea was to Cuvier, as it is to most modern zoologists, but for very different reasons, unverified and basically absurd. Transmutation by the accumulation of alterations, great or small, would thus be impossible. [Coleman, W. (1964) Georges Cuvier: Zoologist, Harvard University Press, Cambridge, Mass. pp 172-73.] [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p18.] But there were an increasing number of observations, particularly geological, that were difficult to reconcile with the Mosaic account. It was increasingly obvious to most geologists that none of the known natural processes, such as water or wind erosion, could have shaped the Earth's surface in a mere six thousand years. These processes cause virtually no perceptible change even over centuries, yet the book of Genesis implied that the Earth had been created in the relatively recent past, only six thousand years ago, according to some biblical chronologists. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p21.] Darwin was a Bible-quoting fundamentalist and a believer in the special ]3[ creation and fixity of each species: . I did not then in the least doubt the strict and literal truth of every word in the Bible , .. 9 Whilst on board the Beagle I was quite orthodox, and I remember being heartily laughed at by several of the officers (though themselves orthodox) for quoting the Bible as a unanswerable authority on some point of morality. 10 [Darwin, F. (1888) ed, The Life and Letters of Charles Darwin, 3 vols, John Murray, London.] [9. ibid, vol 1, p45.] [10. ibid, vol 2, p307.] [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p25.] For Darwin the Beagle proved the turning point of his life, a liberating journey through time and space which freed him from the constraining influence of Genesis. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p25.] It was Darwin's geological observations on the Beagle which first sowed seeds of doubt in his mind as to the historicity of the Genesis account of creation. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p25.] Whether Darwin himself made the transition while on board the Beagle is difficult to assess from his own writings. Precisely when he came to believe in evolution, whether it was a gradual dawning, or a sudden realization, we will probably never know. What is cenain, however, is that the biological observations he made on the voyage, particularly those relating to geographical variation, played a crucial role in the development of his evolutionary thinking. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p27.] It was the existence of so many distinct, yet intimately related, species scattered on the islands of the Archipelago which planted the idea of organic evolution in Darwin's mind. As he noted in his journal:16 The distribution of the tenants of this archipelago would not be nearly so wonderful, if, for instance, one island had a mocking-thrush, and a second island some other quite distinct genus; - if one island had its genus of lizard, and a second island another distinct genus, or none whatever- or if the different islands were inhabited, not by representative species of the same genera of plants, but by totally different genera .... But it is the circumstance, that several of the islands possess their own species of the tortoise, mocking-thrush, finches, ]4[ and numerous plants, these species having the same general habits, occupying analogous situations, and obviously filling the same place in the natural economy of this archipelago, that strikes me with wonder. [Darwin, C. (1845) The voyage of the Beagle, new cd (1959) by J.M. Dent, London, p382.] [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p29.] The Beagle revealed to Darwin a new world, one that bore no trace of the supernatural drama that Genesis implied, and one which seemed impossible to reconcile with the miraculous biblical framework he himself had accepted when he left England. All the new evidence seemed to point to an immensely long geological past, and nowhere could he see evidence of supernatural catastrophes or interventions interrupting the course of nature. The doctrine of the fixity of species was contradicted by the sorts of observations he had made on the Galapagos Islands which suggested strongly that species did in fact change under the agency of entirely natural processes. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p35.] Although nothing that Darwin had witnessed on the Beagle implied that evolution on a grand scale had occurred, that the major divisions of nature had been crossed by an evolutionary process, the old typological discontinuous view of nature seemed far less credible. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p35.] 2 The Theory of Evolution The core idea of the Origin, the idea that living things have originated gradually as a result of the interplay of chance and selection, has a long pedigree. It can be traced back from the views of current advocates of Darwinian orthodoxy such as Huxley, Mayr and Simpson to Darwin and from Darwin via Hume in the eighteenth century right back to the materialistic philosophers of classical times. The idea is clearly expressed in the philosophies of Democritus and Epicurus and by many of the even older Ionian nature philosophers such as Empedocles. [Michael Denton: Evolution, A Theory in Crisis, Adler & Adler Publishers 1986, p37.] Hume's explanation to account for the design of living things, which he gives in his famous dialogue concerning natural religion, is basically the same. He proposed that the world was composed of a finite number of particles which ]5[ were in perpetual random motion. In unlimited time the particles enter into every combination possible. Occasionally they enter into stable conformations which tend to persist. 3 A finite number of particles is only susceptible of finite transpositions, and it must happen in an eternal duration that every possible order or position must be tried an infinite number of times ... the continual motion of matter, therefore, in less than infinite transpositions must produce this economy or order and by its very nature that order, when once established supports itself for the many ages.