Darwin's Origin of Species

by Janet Browne

  Throughout, he displayed an enthusiasm that FitzRoy and the other officers described as very engaging. They nicknamed him ‘Philos’, standing for ‘Ship’s Philosopher’, or sometimes ‘Flycatcher’, and teased him about the natural history rubble that he accumulated on deck. For the full five years he remained good-natured and easy to get along with – a considerable feat on a small ship crammed with seventy-four men and boys. Only sea-sickness set him back. Darwin constantly fell sick when the ship was underway and never gained any sea legs. The captain and his cabin-mates were very sympathetic.

  He was also free to explore every ramification of his love for natural history. Darwin took his responsibilities seriously. He made collections of birds, vertebrates, invertebrates, marine organisms, insects, fossils and rock samples, and a fair collection of plants. These were regularly shipped back to Henslow in Cambridge, who kept hold of them until his return. It was a good collection, including many unusual and new species, but it is still useful to note that it is probably only Darwin’s subsequent fame that has made these animals and plants such important trophies in today’s museums and institutions. In addition Darwin dissected and observed under the microscope that he kept in his cabin, keeping notes as he went along. All the time, he made extensive observations on habitat, behaviour, colouration, distribution and suchlike, creating a careful paper record that would form the basis of several books and articles after the voyage ended. He told his sisters and friends of the great satisfaction that these activities gave him. ‘Looking backwards, I can now perceive how my love for science gradually preponderated over every other taste,’7 he said late in life. During these years he trained himself to see – to look attentively at details – and to record. In retrospect, perhaps the most significant aspect of the voyage was therefore not the huge collection of specimens, the sights, the dangers, or even the personal maturation and friendships he experienced, but the opportunity to develop an intense understanding of the variety of the natural world. By the time he came back he had stopped shooting. ‘I discovered, though unconsciously and insensibly, that the pleasure of observing and reasoning was a much higher one than of skill and sport.’8 The impact of seeing so many different places and people and encountering such a variety of natural habitats and forms of life was incalculable. His eventual prominence as a naturalist ultimately rested on these long and careful days learning to observe and think about nature’s prodigal abundance.

  Darwin’s mental development on the voyage should consequently be given its due. Any number of young men attended Grant’s or Jameson’s or Sedgwick’s lectures, any number of enthusiasts collected natural history specimens. Few of them asked the kind of questions Darwin came to ask. Sometimes Darwin saw organisms that were excellently adapted to their way of life, just as William Paley had described. Sometimes they were very poorly ‘designed’. Many of these issues were only fully explored after the ship returned in 1836. None the less, in the introduction to Origin of Species Darwin stated that three findings from the voyage were the starting point for all his views. These were the fossils he dug up in Patagonia, the geographical distribution patterns of the South American Rhea (ostrich), and the animal life of the Galápagos Archipelago.

  The fossils were an extraordinary find. Located near Bahia Blanca (south of Buenos Aires), these remains of gigantic extinct mammals were later identified by London’s museum experts as belonging to previously unknown species of Megatherium, Toxodon and Glyptodont. Darwin noted that the extinct animals were built on broadly the same anatomical plan as the current inhabitants of the pampas. There seemed to be a continuity of ‘type’ over long periods of time. Then, in the far south of present-day Argentina, he collected a species of Rhea (well known to the local inhabitants), which was smaller than the northern form. He liked to tell a funny story about this Rhea. The ship’s company had caught a bird for the cooking-pot and it was not until it was half-eaten that Darwin realized that it was an unknown species he wanted for his collection. The bits that were left were later named Rhea darwinii in his honour (the name is now changed). He afterwards used the two kinds of Rhea to illustrate the fact that closely related species do not generally inhabit the same area – they are mutually exclusive. To his mind, it looked as if there might be some kind of family links either across time or in geographical space. He began to wonder why there should be such connections.

  As the ship moved, so did Darwin’s thoughts. In September 1835 the Beagle left South America and struck out for the Pacific, with its first call at the Galápagos Islands. Ironically, Darwin did not notice the diversification of species on the Galápagos Islands during the Beagle’s five- week visit, even though the English official on Charles Island (Isla Santa Maria) informed him that the giant tortoises were island-specific. However, everything about the islands im pressed him greatly. He was fascinated by the iguanas that overran the land and seashore, giant tortoises, mocking birds and boobies, as well as the arid volcanic landscape and curious lichen-festooned trees. These fourteen tiny specks of land were right on the equator, swept by cold southern waters that brought fur seals and penguins to their shores. They were mostly within sight of each other but separated by deep, treacherous sea channels. The animals and birds were not used to human intruders and were very trusting in their behaviour. For the Beagle men it was almost like encountering a Garden of Eden. Darwin rode a tortoise, caught an iguana by its tail and came so close to a hawk that he could push it off the branch with his gun.

  The birds that he collected were bundled together in a single bag: he never suspected that their individual location might be important. He did notice that the mocking birds seemed different from island to island, and were different again from those of continental South America. This observation was sufficiently perplexing for him to mention it in his ornithological notes some months later on the return voyage. He appears to have thought that the birds might be geographical varieties of one or more South American species – and reflected on the problem:

  When I see these islands in sight of each other, and possessed of but a scanty stock of animals, tenanted by these birds, but slightly differing in structure, and filling the same place in nature, I must suspect they are only varieties… If there is the slightest foundation for these remarks the zoology of archipelagos will be well worth examining; for such facts would undermine the stability of species.9

  At Cape Town in June 1836 he may have discussed the creation of species by natural law with John Herschel, the great astronomer, at that time living in South Africa to observe the southern heavens. It is unlikely, however, that Herschel would have contemplated a natural origin for species. He had recently read Lyell’s Principles of Geology. Herschel wrote to Lyell, whom he knew personally, to declare that the origin of species was a divine mystery, ‘that mystery of mysteries’ as Darwin later put it.

  One other feature of the voyage proved of lasting significance although Darwin did not refer to this in the Origin of Species. His intellect was permanently stirred by the diverse human populations he met, and his Beagle writings contain colourful references to the gauchos, with whom he travelled across Argentina, Patagonian Indians, statuesque Tahitians, fierce Maoris and Australian aborigines as well as missionaries, colonists and slaves. Throughout he expressed the view that humans were all brothers under the skin. In fact a strong antipathy to slavery in any form was crucial to his developing views about the unity of all mankind. Anti-slavery politics were integral to his family viewpoint in general, for the first Erasmus Darwin had been an active promoter of emancipation causes in Britain and in his poems publicly praised Josiah Wedgwood’s famous medal emblazoned with the motto ‘Am I not a man and a brother’. Darwin’s father, sisters and cousins all supported the anti-slavery movements of the early nineteenth century – as did he. And the Beagle was travelling the world just when these mass philanthropic movements reached their pinnacle in Britain with the Emancipation Act of 1832.

  The only time that Darwin was really an
gry with Captain FitzRoy was over an incident at a great estância in Brazil, where the slave-owner called all his men before him and asked whether they wished to be free. No, they answered. Talking in the cabin afterwards, FitzRoy complacently took that response as a simple truth until Darwin pointed out that no slave would risk any words to the contrary. The captain stormed out of the cabin, saying that they could not live together any longer. On another occasion Darwin was given an insight into the slaves’ attitudes: one day in Brazil, as he was being ferried across a river by a coloured boatman, he absentmindedly waved his arms to give directions and was horrified to see the man cower in fright because he thought he would be hit.

  But Darwin’s most unsettling encounter was with the indigenous inhabitants of Tierra del Fuego. He was deeply shocked by his first sight of them in their rudimentary wigwams, a canoe-going people who seemed to him to possess no resources whatsoever except the ability to make fires, after which the region was first named by Magellan. ‘The sight of a naked savage in his native land is an event which can never be forgotten.’10 The shock was all the more vivid when compared with three Anglicized Fuegians on board, who had been taken to England by FitzRoy on the previous Beagle voyage, educated by a clergyman, and were now being repatriated in a Protestant mission station that FitzRoy intended setting up close to their home territory in inland Tierra del Fuego. In London the three had quickly adopted European habits and speech. Now, Darwin was astounded at the difference between the Anglicized Fuegians and the indigenous tribes to which they belonged. ‘I would not have believed how entire the difference between savage & civilized man is. It is greater than between a wild & domesticated animal.’11 The fact that near-savages could be civilized (as Darwin saw it) confirmed his belief that, under the skin, humans were all one species. This belief remained a lifelong commitment. During the Beagle’s time in the far south Darwin and FitzRoy were disappointed to see that the three Anglicized Fuegians rapidly reverted to the aboriginal state. The trappings of civilization were only ephemeral, the two travellers mused.

  Most important of all, however, was the attention Darwin paid to geology. He was delighted by the grand theoretical schemes he found in Charles Lyell’s Principles of Geology and excited by Lyell’s rejection of biblical authority as a source of geological explanation. The book was commonly regarded as theologically radical. Although Henslow had recommended that Darwin should read it, he also advised ‘on no account to accept the views therein advocated’. What bothered Henslow – and what ultimately became so appealing to Darwin – was Lyell’s insistence that the earth’s changes were not necessarily progressive in nature. The surface of Lyell’s earth was forever on the move, but the alterations were not directed by God towards any future point. At that time, few geologists believed that the earth had literally been created in six days. They saw the Bible more as a metaphor for the stages that the earth must have undergone from its beginnings to the present day. Yet most geologists connected this sequence with the broad outline of earth history indicated in the Judeo-Christian tradition – that is, that the earth was stocked by divine fiat and progressively shaped in six or seven stages by God for human habitation.

  In his Principles of Geology Lyell challenged this view by claiming that the earth’s surface showed no evidence of stages. Instead it constantly experiences innumerable, tiny, accumulative changes, the result of natural forces operating uniformly over immensely long periods. These changes were for the most part so small that they were usually unnoticeable to the human eye. But if they were repeated over many epochs they added up to substantial effects. He shocked his colleagues by insisting that the earth was immeasurably old, that it had no beginning and no vestige of an end, and would continue endlessly in never-ending geological cycles characterized by the successive elevation and subsidence of great blocks of land relative to the sea. There was no God-given direction or progression. The great Cambridge philosopher William Whewell, himself very interested in geology, dubbed this approach to the earth ‘uniformitarianism’.

  In Lyell’s estimation geology also included what we now call biology. He argued that there were no successive sets of animals and plants either, and that each species had been created in a piecemeal fashion, one by one. By saying so, he found himself in the middle of a logical dilemma. Gradualism in geology implied gradualism in biology – if the rocks slowly transform in a seamless web of change, then so could animals and plants. But since Lyell was not prepared to believe in any kind of transmutation in living beings, he quickly fell into a tangle of equivocation. In order to demonstrate that he did not believe in evolutionary matters, he provided a long and aggressive attack on Lamarck. All the available evidence indicates that Darwin read this attack with mounting interest: although the words were negative he was exposed to evolutionary information that was to play a significant part in his intellectual growth. From Robert Grant’s enthusiasm in Edinburgh to Charles Lyell’s opposition in Patagonia, Darwin recognized the passion that transmutation inspired – and the hostility.

  Darwin went on to absorb Lyell’s teachings, using his geological ideas to explain the landforms he saw; they supplied the groundwork of his three later books on the geology of South America. Here and there he audaciously produced explanations for geological structures that he thought were better than Lyell’s own proposals. One was a theory for the origin of coral reefs. Another was the recent elevation of the Cordillera. At a deeper level, too, he adopted Lyell’s creed of gradual change. ‘The science of geology is enormously indebted to Lyell – more so, as I believe, than to any other man who ever lived.’12 Another tribute was paid in a private letter that Darwin wrote after the Beagle returned:

  I always feel as if my books came half out of Lyell’s brain, and that I never acknowledge this sufficiently… the great merit of the Principles was that it altered the whole tone of one’s mind, and therefore that, when seeing a thing never seen by Lyell, one yet saw it partially through his eyes.13

  Without Lyell, it could be said, there might not have been any Darwin: no intellectual insights, no voyage of the Beagle as commonly understood. Darwin’s thoughts began to circle around the notion of small changes leading to large effects. In doing so, he took one of the most important conceptual steps of his personal journey. For the rest of his life, he believed in the power of small and gradual changes. Afterwards, when working on evolution, he used the same concept of small and accumulative changes as the key to the origin of species.

  At last the ship turned homewards and Darwin began to review his achievements. All the evidence points to the conclusion that he did not develop a theory of evolution on the voyage. Instead, he returned full of ideas and scientific ambition, determined to make sense of the riot of information he had acquired. Few young men ever had such an opportunity to see a world in its entirety. He was deeply impressed by nature’s prodigality, the colour, variety and abundance on the one hand, and raw struggle and harshness on the other. And even though he came gradually to discredit the Bible as an authoritative record of real events, he was unwilling completely to give up his belief, partly because of this intense appreciation of nature’s marvels. While standing in the middle of the grandeur of a Brazilian forest, he declared, ‘it is not possible to give an adequate idea of the higher feelings of wonder, admiration, and devotion which fill the mind’.

  He thought about the future too. For much of the voyage he apparently still intended to take up life as a country parson, although this prospect became progressively less appealing as his confidence as a naturalist grew. Towards the end, however, he told his sisters that he wished to pursue natural history as a vocation and hoped to be accepted as an equal in the scientific community. He wanted to be an independent gentleman-expert like Lyell, free to write books and follow his natural history inclinations, not tied to a university like Henslow, nor to the church patronage system like Fox. As the mental image of the parsonage among green English fields crumbled, there was the figure of Lyell beckoning be
hind it. ‘It appears to me, the doing what little one can to encrease [sic] the general stock of knowledge is as respectable an object of life, as one can in any likelihood pursue.’14 This shift in his ambitions rested on a conviction that he had new and noteworthy things to say. It also depended on the goodwill of his father in releasing his inheritance.

  Darwin stepped on to the dock at Falmouth in October 1836 a changed man but not yet an evolutionist.

  CHAPTER 2

  ‘Atheory by which to work’

  Five years away on an Admiralty ship was a long time. When Darwin looked about him he could not help but notice how much England had changed. Railways were snaking across the land where stagecoaches had once travelled, towns crept relentlessly outwards, shops, chapels, factories and newly built churches sprouted everywhere. This was the England of Dickens’s classic tales.

  It is often hard to remember just how unstable British society was in these first four decades of the nineteenth century. The nation came as close to revolution as it ever had: conflict between landlords and manufacturers, workers against masters, province versus metropolis, the hungry and mutinous threatening the commercially minded, individualistic middle classes. Benjamin Disraeli’s imagery of two nations, rich and poor, was not fanciful. ‘The People’s Charter’, drawn up in 1838, with its famous six points – suffrage, the ballot, equal electoral districts, abolition of property qualifications, payment for MPs, and annual parliaments – frightened the political establishment deeply. A huge demonstration in 1839 ended in a bloody confrontation with the military. The last great Chartist rally on Kennington Common in 1848, although more peaceable and socialist in character, additionally reflected the agonies of Irish famine and political suppression. Karl Marx, surveying Britain through the eyes of his mill-owning friend Friedrich Engels in the 1840s, argued that capitalism was doomed to choke on its own surplus.