<p> Darwin’s Legacy John Campbell August 2004</p><p>Charles Darwin should be on any list of the three greatest scientists of all time. Evolution by Natural Selection is the central organizing principal of biology and Darwin not only proposed this theory but also provided a stupendous amount of evidence in support of it. Newton and Einstein made great contributions to science in the form of developing powerful mathematical formulas that could be used to accurately predict a wide range of phenomena. Darwin’s accomplishment was not like this; his theory is not as mathematically precise. Rather his achievement was to show us how things came to be, how design is created through a simple natural process. As such he challenged and defeated religious claims of knowledge. Today informed opinion relies upon evolutionary theory to answer our big questions such as ‘who are we?’ and ‘where did we come from?’.</p><p>In many ways, during his early years, Darwin did not appear to hold the potential of a great scientist. He showed an interest in natural history and was an avid collector of beetles but he dropped out of medical school and did not distinguish himself at university in Cambridge. His normally kind and patient father, a respected country doctor, anguished over Charles’s future and concluded he was fit for nothing better than the ministry, not a lofty ambition in a family of free thinkers: You care for nothing but shooting, dogs and rat catching and you will be a disgrace to yourself and all your familyi.</p><p>There were however some signs of potential. While avoiding his medical classes in Edinburgh he delved into natural history studying chemistry, geology and ornithology. He became acquainted with a prominent naturalist, Robert Grant, and collected biological samples with him. Around this time he also published his first scientific paper concerning the eggs of a marine leech.</p><p>At Cambridge, although his marks were not stellar, he became the confidant of a respected botany professor, John Henslow. Darwin spent as much time as he could in Henslow’s company and they seemed soul mates, sharing a deep interest in many subjects to do with natural history. Darwin was described by some Cambridge Dons as ‘the man who walks with Henslow’.</p><p>It was through Henslow that Darwin’s name was given to Captain Fitzroy of the Beagle as a recommendation for the post of Ship’s Naturalist and Captain’s Companion on a round the world charting expedition for the British Admiralty. Apart from continuous bouts of sea sickness, he took to his posting like a duck to water. Reading excerpts from his logs there is no doubt that he immersed himself in the duties of a naturalist thrust into lands largely unexplored by Europeans. </p><p>"As far as I can judge of myself I worked to the utmost during the voyage from the mere pleasure of investigation, and from my strong desire to add a few facts to the great mass of facts in natural science."ii</p><p>He collected vigorously and brought to England some 1,529 species pickled in spirits and 3,907 labelled skins, bones, and other dried specimens. Many of these specimens he sent back to England during the course of his voyage to trusted colleagues such as Henslow. His collection was so respected that he was the toast of the scientific community on his return to England at the end of his four year round the world expedition.</p><p>Darwin’s collection was studied by experts on the various specimen types. He presented the Museum of the Zoological Society with a gift consisted of 450 birds and 80 mammals he had collected and these specimens were studied by John Gould. Amongst the birds Gould indentified 13 species of finches taken from the Galapagos Islands. After much thought, these finches were seminal in triggering his ideas of evolution by natural selection. The finches differed largely in their types of beaks; some were for eating insects, some for seeds and some even for wood pecking. This is highly unusual. Usually, in an ecology, there are different types of birds adapted for each of these ways of making a living. Darwin’s finches, apart from their beaks, appeared remarkably alike. Darwin’s eventual conclusion was that a single ancestral pair of finches had made it to the newly formed volcanic islands and that over the generations variations in the offspring had gradually been selected to fill many of the ecological niches available to birds. Selection of characteristics, such as beak type, useful in each of their niches and the associated behaviour served to isolate these groups of finches from each other until they became separate species.</p><p>Here was evidence indicating that the categories of species was not something laid down for all time by the Creator. It was a dynamic evolving process. Darwin further reasoned that evolution occured whenever reproduction took place with some variations, meaning that there are some differences in the offspring. Then, given that there were always more offspring than could be supported, those with variations favouring their survival would be the ones to persist and pass on their traits to future generations. In this manner living things change and become continuously more adapted for survival.</p><p>This is a very simple mechanism: 1) Reproduction 2) Offspring have some variation 3) The variation determines which offspring are more likely to survive and live to reproduce.</p><p>It is very simple and yet it is clear, upon investigating the evidence, that it is responsible for creating all biological design. Darwin was instrumental in provinding the initail evidence in support of his theory of Evolution by Natural Selection. He analysed and studied a number of plants and animals in great depth including orchids, earth worms and barnacles and compellingly demonstrated how the forces of evolution had created the myriad detailed characteristic displayed by them.</p><p>In Darwin’s day the prevailing argument for the existence of God was the Argument from Design. Darwin himself was initially a believer in this argument but his studies convinced him otherwise:</p><p>The old argument from design in Nature, as given by Paley, which formerly seemed to me so conclusive, fails, now that the law of natural selection has been discovered. We can no longer argue that, for instance, the beautiful hinge of a bivalve shell must have been made by an intelligent being. like the hinge of a door by man.iii </p><p>Reverend Paley, to whom Darwin refers, had argued that if we were to find a pocket watch in the woods and were to examine it, it would be clear that it must have been created by a watch maker. Nothing so intricately designed could be created by accident and its very existence was proof of a watch maker, a creator. So too, the natural world exhibits exquisite design which therefore proves the existence of a creator of the natural world; God. </p><p>Puzzlingly this argument is widely accepted in Western thought as the most compelling ever devised for the existence of God. It is puzzling because it is obviously deeply flawed. That there are well designed life forms is evidence of the existence of a means of producing biological design. That God is that means of producing this design, specifically the Christian God described in the bible, is a huge and totally unsupported leap. That this argument could be given serious consideration as a ‘proof’ demonstrates how completely religious thought through history has overwhelmed rationality. Darwin destroyed this argument by discovering the actual means by which this design was accomplished supported by voluminous detailed evidence that has convinced nearly everyone who has ever considered it. We all enjoy in this his legacy the opportunity to see beyond myth and fairy tale concerning the ultimate nature of the universe in which we live. The theory of evolution is now the central organizing principal of biology and the weight of evidence for it is so overwhelming that there are virtually no scientific voices opposing it. While many of the great scientific discoveries, such as those of Newton and Einstein, are express in highly arcane mathematical language, the discovery of Darwin is very accessible. Origin of Species created a public sensation when it was published and others of his books including the Ascent of Man were best sellers.</p><p>The Argument from Design met its public Waterloo in an exchange between Darwin’s Bulldog, Thomas Huxley, and ‘Soapy Sam’ Wilberforce, bishop of the Anglican Church. At the time there was great public interest in Darwin’s theory. The church and its supporters saw evolution very much as a threat to religious authority and to their right to pontificate on the natural world. A public discussion was organized by the British Association in Oxford on 30 June 1860 and had a huge turn out. Bishop Wilberforce and like minded distinguished naturalist and clerics were present to provide views opposed to Darwin. Huxley, a great advocate of Darwin’s theory was present but did not speak initially as he did not believe that such a public audience would be sympathetic. Wilberforce gave a long talk in which he pandered to the audience and heaped scorn on evolutionary theory. At the end he goaded Huxley by asking him, rhetorically, on whether it was on his grandmother’s or his grandfather’s side of the family through which he was related to an ape. Huxley rose and said that he would rather be related to an ape than to one who would use his skill and intelligence to disguise the truth. </p><p>For some reason his rejoinder brought down the house. While it is unclear exactly what was said in the debate (the above is only one of many versions) it is clear that Huxley was widely perceived to have achieved a famous victory. Through the efforts of Huxley and a small group of Darwinian enthusiasts in many engagements with their opponents the tables were turned. The Argument from Design was no longer intellectually defensible and the religious establishment retreated from their claims for the literal truth of the book of Genesis. This was perhaps the last time in the western world that organized religion (other than American fundamentalism) was able to seriously challenge science regarding the physical nature of the world.</p><p>Unlike Einstein or Newton, Darwin’s theory is widely accessible. The public, even during Darwin’s time were very aware of its implication that people are part on the web of living things on earth and are closely related to its other animals. This is not always the case for great science. For many years after Einstein’s death the common view amongst laymen was that only a handful of people in the world could understand relativity.</p><p>After his death although his theory became the only intellectually defensible explanation of variety in the living world, its development languished. The mechanism by which reproduction and heredity was achieved were unknown and there was debate on its theoretical merits. Early in last century Rutherford, the leading physicist of his day claimed that he had disproven evolution through his calculations demonstrating that no known mechanism could power the sun for the length of time required for Darwin’s theory to produce the remarkable variety of the natural world. It was not until mid way through the next century that the details concerning the nuclear reactions powering the sun became known to science.</p><p>Unknown to Darwin an Austrian Monk, Gregor Mendel, had read Darwin’s work with much interest and in 1865 published a little known paper showing the details of how characteristics in peas are inherited. This was important to the theory of evolution as even Darwin saw it as a weakness that the inheritance mechanism was unknown and he could not see how characteristics could stay distinct and not get blended when inherited by offspring. After all, each offspring has another parent from whom they also inherit some variation of the same characteristic. Unfortunately Mendel’s paper did not come to the attention of scientists working on evolutionary theory until 1902 but then was recognized as further evidence for evolution.</p><p>The 1920s in America were an era of ferment. New ideas such as evolution, Freudian theory and abstract art appealed to many in the wider culture. This provoked a wave of revivalism amongst society’s more traditional members who encouraged the authorities to crack down on threats to their way of life. Tennessee had a law prohibiting the teaching of Darwin’s theory of evolution in public schools and a young teacher, John Scopes, was charged with breaking this law. Public attention focused on this case and it attracted two of the most famous lawyers of the age, Clarence Darrow and William Jennings Bryan, three time Presidential candidate, to defend and prosecute the case. The trial, held in the little town of Dayton, had a carnival atmosphere and its proceedings were front page news in the major national newspapers. With over 5,000 spectators in attendance it was held outside on the courthouse lawn for lack of room inside. The concluding days of the trial were high drama11:</p><p>On the seventh day of trial, Raulston asked the defense if it had any more evidence. What followed was what the New York Times described as "the most amazing court scene on Anglo-Saxon history." Hays asked that William Jennings Bryan be called to the stand as an expert on the Bible. Bryan assented, stipulating only that he should have a chance to interrogate the defense lawyers. Bryan, dismissing the concerns of his prosecution colleagues, took a seat on the witness stand, and began fanning himself. </p><p>Darrow began his interrogation of Bryan with a quiet question: "You have given considerable study to the Bible, haven't you, Mr. Bryan?" Bryan replied, "Yes, I have. I have studied the Bible for about fifty years." Thus began a series of questions designed to undermine a literalist interpretation of the Bible. Bryan was asked about a whale swallowing Jonah, Joshua making the sun stand still, Noah and the great flood, the temptation of Adam in the garden of Eden, and the creation according to Genesis. After initially contending that "everything in the Bible should be accepted as it is given there," Bryan finally conceded that the words of the Bible should not always be taken literally. In response to Darrow's relentless questions as to whether the six days of creation, as described in Genesis, were twenty-four hour days, Bryan said "My impression is that they were periods. </p><p>Bryan, who began his testimony calmly, stumbled badly under Darrow's persistent prodding. At one point the exasperated Bryan said, "I do not think about things I don't think about." Darrow asked, "Do you think about the things you do think about?" Bryan responded, to the derisive laughter of spectators, "Well, sometimes." Both old warriors grew testy as the examination continued. Bryan accused Darrow of attempting to "slur at the Bible." He said that he would continue to answer Darrow's impertinent questions because "I want the world to know that this man, who does not believe in God, is trying to use a court in Tennessee--." Darrow interrupted his witness by saying, "I object to your statement" and to "your fool ideas that no intelligent Christian on earth believes." After that outburst, Raulston ordered the court adjourned. The next day, Raulston ruled that Bryan could not return to the stand and that his testimony the previous day should be stricken from evidence.iv </p><p>The defense requested a verdict of guilty so that the state law banning the teaching of evolution could be challenged in an appeal. The jury returned a guilty verdict, Scopes got a $100 fine, the case was appealed and the verdict overturned on a technicality. </p><p>More importantly, of the 15 states that had anti-evolution legislation pending, only two, Arkansas and Mississippi proceeded. </p><p>In 1953 the structure of DNA was revealed by Watson and Crick. DNA encompasses the molecular framework for Darwinian reproduction and heredity. DNA is a replicator and is at the seat of the Darwinian algorithm, the essence of evolutionary theory. It is DNA that is at the heart of reproduction, it is the molecular form in which the information of heredity is communicated and it provides a mechanism for the variation in characteristics essential to the Darwinian algorithm. Since its discovery study of its properties and functionality has probably been the main research area of Biology. Throughout the resulting rapid accumulation of scientific knowledge concerning genetics and evolutionary history, no evidence has posed a serious challenge to Darwin’s theory. Indeed, the theory is successfully used day in and day out to explain evidence found by researchers. </p><p>Today Darwin’s legacy is very much with us and the theory of evolution is integrated into many people’s world view. Essential to the environmental movement is the understanding that all life is related and that we are greatly dependent on this web of living things. There are no longer any laws in western democracies forbidding the teaching of evolution. In America the best the religious fundamentalist can manage is to allow the teaching of ‘Creation Science’ along with evolution in some states. Non-fundamentalist Christian religions have given up their attacks on Darwinian Theory. Many are happy to leave explanations of the physical world completely to science. Even the Pope has accepted evolution as fact. One can say that the Argument from Design concerning the creation of the biological world has been thoroughly refuted and even most of the religious establishment has accepted this outcome.</p><p>Following in Darwin’s tradition many of the foremost biologists of the age such as Richard Dawkins and Stephen J. Gould continue to publish best sellers describing the evolutionary process. One of Dawkin’s books, The Selfish Gene, contained an important addition to the theory of evolution. It posited the existence of the ‘meme’ a second replicators functioning according to the Darwinian algorithm. Unlike genetics that operates in the biological realm, memes operate in the cultural realm. A substantial body of scientific work, described in previous chapters, is now assembled providing evidence that the evolution of culture is due to this replicator. </p><p>There has never been an Argument from Design concerning the creation of culture. Culture displays a huge amount of design but no religion has suggested that God should be credited with creating it. The theory of memetics has had relatively little opposition from the religiously inclined.</p><p>Once the argument from design was crushed in the biological arena due to the light of science illuminating the true source of design in the living world, its defenders retreated to other areas where ignorance still prevails. Today the remaining major sanctuary for the Argument from Design is in the area of basic physics and cosmology. Science is a cumulative body of knowledge and does not claim to have all the answers (only the known answers in its areas of expertise). There are always unanswered questions beyond the current grasp of science. These questions often seem mysterious and even scientist speculate about ultimate causes. A quick Google search will bring up numerous religious sites claiming God inhabits these areas of scientific ignorance and trumpet quotes from leading scientists such as this one by Paul Davies: There is for me powerful evidence that there is something going on behind it all....It seems as though somebody has fine-tuned nature’s numbers to make the Universe....The impression of design is overwhelming.v</p><p>As Davies indicates the universe seems exquisitely designed to produce complexity such as atoms, stars and life. The best theories of Physics and Cosmology work exceedingly well and predict most experimental evidence. However they have about 35 basic parameters, values for physical properties like the mass of the electron, which are not predicted but must be specified. No one knows why they have the values they do. These parameters have exactly the right values so that the theory predicts a universe exactly like ours. If they were only slightly different the theory predicts that nothing more complex than hydrogen gas could exist in the universe. </p><p>The universe is superbly designed to produce complexity and as this design is extremely unlikely to have occurred by accident many have taken this as evidence for a creator and in the absence of any other obvious candidate that creator is assumed to be God. This line of reasoning has come to be known as the Theological Anthropic Principle and as Lee Smolin writes, parts of the argument are persuasive:</p><p>It should be admitted that it does have force: the discovery of a craft as complex as an airbus on a new planet would be good evidence for intelligent life there. But this argument has force only so long as there are no plausible alternative explanations for how the choice might have been made. In the case of biology, natural selection provides a falsifiable and so far successful explanation, which renders unnecessary the argument from design.vi</p><p>The lesson learned from biology is that when unexplained design exists there must exist a creator and we should look for this creator, not in the form of a God but rather in the form of a Darwinian process. Smolin has posited an evolutionary process that serves to create universes just right for producing stars and once you have stars further complexity such as life is not a huge leapvii,viii. Smolin calls his theory Cosmological Natural Selection. </p><p>The basic idea is that our universe is a child universe which was created when a black hole was formed in a parent universe. The forming of this black hole and the creation of our universe are what we refer to as the Big Bang. The theory speculates that the black hole collapse in the parent universe results in a ‘bounce’, an expansion, of a new universe unreachable from the parent universe. In the parent universe all that can be observed is the horizon of a black hole. Our universe inherited its 35 basic parameters, with slight variations, from its parent. By this method those universes with parameters fine tuned to produce black holes have offspring universes that vary only slightly from them. The theory predicts that the vast majority of universes will come to have parameters with values statistically clustered around the ‘just right’ fine tuning to produce stars and black holes and, as a side effect, life.</p><p>Cosmological Natural Selection, although speculative, is a scientific theory, meaning it makes definite, falsifiable predictions that can be tested by experiment in the near future. It may not prove to be the right theory, it may need some alteration but it does posit a plausible, testable mechanism. </p><p>We have three theories that account for all the design seen in the universe; in cosmology, in the living world and in culture. There remains no room for the argument from design. Die hard proponents of the argument from design could claim that there must be something behind Darwinian processes, but of course this is grasping at straws. This retreat of God as an explanation of design from areas where knowledge is discovered to areas of ignorance is a recurring pattern. Surely the message is now clear; invoking the concept of God is not a satisfactory explanation for any detectable phenomena.</p><p>Universal Darwinism is a satisfactory explanation for the source of all design. It is a scientific theory, it makes clear predictions and it is falsifiable. It will evolve as our theoretical and experimental knowledge expands but it rests on a vast body of firm evidence and is likely secured.</p><p>This is Darwin’s legacy. It is a body of knowledge that is widely accessible by anyone with the interest and commitment to explore their true situation, their place in the universe. Unlike the theories of Newton’s or Einstein’s it does not require deep knowledge of arcane mathematics for a full appreciation. Its principals are simple and elegant. Once we become accustomed to its content we see it evident in the world everywhere we look. Darwin’s legacy is to provide us with an accessible doorway to the immortal realm beyond our one-time-only concerns, to the timeless universe that is our spiritual home. i Darwin Charles, The Autobiography of Charles Darwin, Project Gutenberg Release #2010 (December 1999) ii Darwin Charles Robert. The Voyage of the Beagle. The Harvard Classics. 1909–14. iii Darwin Charles, Autobiography (1876), in The Life and Letters of Charles Darwin, ed. Francis Darwin, vol. 1 (London: John Murray, 1888), pp. 307-13. iv Linder Douglas. The Scopes Trial: An Introduction. Famous Trials website: http://www.law.umkc.edu/faculty/projects/ftrials/scopes/scopes.htm, last viewed August 29 2004 v Quotes from Scientists Regarding Design of the Universe website. http://www.godandscience.org/apologetics/quotes.html. Last viewed August 29, 2004 vi L. Smolin, 2004, Scientific alternatives to the Anthropic principal, preprint vii L. Smolin, 2004, Scientific alternatives to the Anthropic principal, preprint viii L. Smolin, 1997, The Life of the Cosmos, Oxford University Press</p>
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