Charles Darwin’s theory of evolution by natural selection has been described as perhaps the most radical scientific theory ever proposed. For atheists such as Richard Dawkins it is the ‘universal acid’ which eats away the traditional view that the world was designed by God, with humans playing a key role in the cosmic drama. Those who want to preserve the traditional values naturally react very strongly, and the fulminations of modern Creationists continue the hostility expressed by many conservative thinkers in Darwin’s own time.

The man who proposed such a controversial idea is accorded an iconic status by those who have to live with the consequences, as either a hero or a villain depending on your point of view. The many celebrations planned for the 200th anniversary of Darwin’s birth indicate the status he has achieved as a founding father of modern science. But the very fact that Darwin is one of the few scientists that almost everyone has heard of means that the world is awash with stories about his life and achievements. These stories are the ‘myths’ of my title, the term referring to accounts of great discoveries which may be based on fact, but which turn out on closer inspection to be distortions or misrepresentations of what actually happened. In the case of Darwin we have a huge amount of archival material surviving, which allows historians to assess the validity of stories told about his life. More important, though, are our efforts to understand how and why the myths were created. Some were part of Darwin’s own self-representation in his autobiography. Others highlight one aspect or another of his work, often making a judgement about what was really significant. A few are almost complete fabrications put out to discredit the theory.

Charles Robert Darwin was born on 12th February 1809. His father was an eminent medical doctor and a wealthy entrepreneur, one of the rising middle class gaining influence as the Industrial Revolution got underway. The young Charles wasn’t very good at school, but he was eventually sent to study medicine at Edinburgh.

Here we encounter our first myth, in this case created by Darwin himself. He found medical studies distasteful and in his later reminiscences he dismissed the period in Edinburgh as of little consequence. He records that he was not impressed when the anatomist Robert Edmond Grant praised the evolutionary theory of the French biologist Jean-Baptiste Lamarck. Grant was a political and cultural radical who would become marginalized within the scientific community. Darwin, ever conscious of his own social status, would not have wanted to admit that he was impressed by so disreputable a thinker. Yet historians studying his papers from this period have shown that he worked with Grant on marine invertebrates and was inspired by Grant’s view that ‘zoophytes’ (corals etc.) formed an evolutionary bridge between the plant and animal kingdoms. The Edinburgh period has thus been reinstated as an important episode in Darwin’s intellectual biography.

Having abandoned medicine, Darwin had to look for another career and it was decided that he should train to become a clergyman. He entered Christ’s College, Cambridge, late in 1827. There is a popular misconception that he was studying for a degree in theology, but in fact he was to take a degree in Arts, the normal prelude to studying for holy orders. He did gain a rather undistinguished degree, but he worked much harder at extra-curricular studies with the professor of geology, Adam Sedgwick, and the professor of botany, John Stevens Henslow.

Darwin’s work with Sedgwick defined the early part of his scientific career, because he gained his first reputation as a scientist in the field of geology, not natural history. He made a geological tour of Wales with Sedgwick, who taught him the new techniques for working out the sequence of geological formations. But Sedgwick was a ‘catastrophist’ – he saw most effects of uplift and erosion as the result of sudden upheavals of the earth’s crust. On the voyage of the Beagle, Darwin read Charles Lyell’s Principles of Geology and was converted to Lyell’s uniformitarian method. This explained all geological formations as the result of gradual changes spread over vast periods of time. Darwin saw the effects of earthquakes in the Andes mountains, and evidence that the mountain range was being raised step-by-step through a long series of earthquakes no more violent than we experience today. On his return he published extensively on South American geology. As far as most people around 1840 were concerned, Darwin was a promising young geologist – not someone they would have expected to make his mark in speculative natural history.

When he left Cambridge he had gained a sound training in both geology and natural history – even if this was done outside the curriculum. It was the professor of botany, John Stevens Henslow, who suggested Darwin’s name to Captain Robert Fitzroy, who was looking for a gentleman naturalist to accompany him aboard H.M.S. Beagle, on the ship’s second voyage to chart the coast of South America. After some trouble with his father, Darwin was given the post, and the Beagle left England in December 1831. She would be away for five years, and would circumnavigate the globe at the end of her duties on the South American coast, calling at the Cape of God Hope in June 1836.

Darwin always said that the Beagle voyage was the turning point in his career. While the Beagle sailed up and down the South American coast, Darwin spent much of his time ashore, undertaking a number of extended exploratory trips across the pampas of Argentina and later in the Andes mountains. He saw the natives of Tierra del Fuego – regarded at the time as some of the most ‘savage’ people on earth. But here I want to focus on a single aspect of his work: his experiences related to biogeography and in particular his work on the Galapagos islands.

Darwin’s work on the geographical distribution of species was one of the most important foundations of his theory. It converted him to what we now call evolutionism and shaped the theory he would develop to replace divine creation. Darwin realized that the best way of explaining where new species came from was to see how representatives from a common ancestral form could branch out in numerous different directions if they became isolated in different locations. There was no single goal of evolution because each isolated population adapted to its new environment in its own way.

All this came to a head in the Galapagos islands, where Darwin found collections of distinct but related species on many of the islands. The best-known example of his discoveries here are what we now call Darwin’s finches, although the mockingbirds were probably more important at the time. There are a number of finch species on the various islands, differing especially in the shape of their beaks, which are adapted to various ways of foraging for food. When Darwin realized that these were distinct species he saw that they made it very hard to take the idea of divine creation seriously. Was one really to believe that the Creator had done separate miracles on each of these tiny islands in the middle of the ocean? It made much more sense to imagine small populations from an ancestral South American species being established on the islands after being blown across the ocean in storms. Each had the adapted to its new home in its own way.

There is a popular belief that Darwin underwent a kind of ‘eureka’ experience on the Galapagos islands, but this is a myth which careful study of his notebooks and letters has exploded. He didn’t realize the significance of the different forms until he was about to leave, and had collected specimens without labelling them to indicate which islands they had been taken from. Fortunately, other members of the ship’s crew had collected more carefully, so Darwin was able to piece together a picture of how the different species were distributed. The conventional understanding of Darwin’s work in the Galapagos is a somewhat distorted view of what is, underneath, a basically sound interpretation of the islands’ significance. In this case the myth even serves a useful purpose by focusesing attention onto biogeography as the key area of science leading Darwin to his discovery.
Soon after the Beagle returned to England Darwin began to look for an explanation of how evolution works.. His notebooks show the process by which he groped his way toward the theory of natural selection. He studied the work of animal breeders, which helped him to see the extent of variation within populations and alerted him to the idea of selection. Was there a natural process that could replace the artificial selection practiced by the breeder? The answer occurred to him when reading Thomas Malthus’ Essay on the Principle of Population. Malthus noted that population pressure would lead to a ‘struggle for existence’, the outcome of which would determine who would live and who would die. Darwin realized that in nature it was those best adapted to the environment which would tend to survive and breed, while the least well-adapted would die off. Here was the basis for the mechanism of natural selection.

Many believe that Darwin refrained from publishing his new theory because of his fear of the public reaction. The possibility of an adverse reaction would have been all too obvious from the feelings of his wife. In 1839 he had married his cousin, Emma Wedgwood, and three years later they had set up home at Downe in Kent. Emma was deeply religious and clearly aware that her husband’s ideas threatened to undermine her traditional beliefs. But there are other reasons why he delayed. He began a major study of the barnacles, which helped his theory by throwing light on the kind of structures that natural selection could produce. Only when he had finished his barnacle books did he begin to write what would have become a three-volume account of his theory, but this was interrupted in 1858 by the arrival of a paper by Alfred Russel Wallace containing the proposal of a theory similar to his own.

This certainly wasn’t a case of simultaneous discovery, because Darwin had been working on the theory for twenty years. Wallace approached the problem from the same initial direction as Darwin – the study of geographical distribution. He was collecting zoological specimens in what we now call Indonesia when he conceived his idea of natural selection. But there were significant differences between their proposals. Wallace made no study of animal breeding and never accepted the analogy that Darwin saw between artificial and natural selection. But there were certainly major similarities to Darwin’s idea and Darwin panicked when Wallace’s paper arrived. His friends organized a joint reading of their papers at the Linnean Society which constitute the first publication of the theory. And he set out to write the cut-down version of his proposed ‘big book’ which we know as On the Origin of Species.

Many conservative thinkers reacted in horror to a theory which seemed to deny not only divine creation, but any role for design or purpose in the natural world. Some of the confrontations have themselves taken on a mythical status. Perhaps the best-known is the confrontation between ‘Darwin’s bulldog’ Thomas Henry Huxley and the bishop of Oxford, Samuel Wilberforce at the 1860 meeting of the British Association for the Advancement of Science. Wilberforce attacked the theory for its tendency to undermine religion and in the classic interpretation of the encounter, Huxley demolished the bishop by claiming that he had rather be descended from an ape than from someone who misused his position to attack a theory he didn’t understand. But modern historians have checked letters and diaries written by people who were there, and have shown that Huxley’s speech was not considered particularly effective. The story of Huxley’s triumph was manufactured by a later generation of Darwinists.

In the course of the 1860s ‘Darwinism’ became widely accepted – but at the time this meant little more than generic support for the idea of evolution. There was widespread doubt that Darwin’s theory of natural selection explained how the process worked. Even Huxley did not think that selection was the whole story. Religious scientists such as the botanist Asa Gray – Darwin’s first champion in America – thought that variation was led in directions beneficial to the species, reflecting an element of design built into the laws of nature by the Creator. Most of the first generation of ‘Darwinists’ believed that something more purposeful than natural selection was at work in evolution.

There is a widespread belief that Darwin’s theory was waekened by his ‘failure’ to appreciate the significance of Gregor Mendel’s work, which subsequently became the foundation stone of modern genetics. But this is another oversimplification. Darwin didn’t read Mendel’s paper, but nor did anyone else at the time, and the few supporters of natural selection in the late nineteenth century were able to develop the theory without the help of genetics. The true source of the difficulties that faced Darwin was not the lack of genetics – it was the inability of his contemporaries to accept that evolution could work solely by trial-and-error.

Darwin recognized the wider implications of his theory at an early stage and had gradually abandoned his religious faith. He was never an atheist, but he certainly became an agnostic, to use the term coined by T. H. Huxley. Creationist websites routinely cite a story that on his deathbed he underwent a conversion, returning to his original Christian faith and, by implication, repudiating his theory. Historian James Moore has shown that this legend has no basis in fact. It had its origins in the writings of an evangelist, Lady Elizabeth Hope, who came to the village of Downe shortly before Darwin died and was given a few words of encouragement by the great man. But Darwin was, in effect, the village squire and he took his social duties seriously. He would be reluctant to speak out against a visiting evangelist – it would send the wrong message and threaten to upset the social order.

Darwin died in the morning of 19th April 1882 at the age of 73 and was buried in Westminster Abbey. It may seem odd that a man whose ideas have been hailed as fatal to all religious belief should be buried in hallowed ground with eminent clergymen in attendance. But to understand the event we need to appreciate its symbolism. To the new generation of professional scientists like Huxley, his theory represented the triumph of forward-looking thinking. It allowed them to present the scientific community as the natural successor to the clergy as the source of authority in a modern nation.

It is only in modern times, following the triumph of the synthesis of Darwinism and genetics, that we have been forced to confront the implications of Darwin’s vision of a world governed solely by trial-and-error, a world – as Richard Dawkins proclaims – with no sign of divine purpose built into it. The result has been the re-emergence of controversies similar to those that first confronted Darwin himself – and I do not think that they will die down so quickly this time.