by A. N. Wilson
Moreoever, Peter and Rosemary Grant, evolutionary biologists from Harvard University, spent over twenty-five summers studying these birds, mainly on the island of Daphne Major. They revealed that the beak changes were reversible – this is hardly ‘evolution’. Beaks adapted from season to season depending upon whether droughts left large, tough seeds, or heavy rainfall resulted in smaller, softer seeds. Even had Darwin noticed the supposed evolution of finches’ beaks on the Galápagos Islands and had thereby become an instantaneous convert to his famous theory, the epiphany would have been wrong.80
Nora Barlow expounded the classic confrontation which the thirteen varieties of Galápagos finch supposedly force upon the observer, the choice between ‘creationism’ as represented by FitzRoy and ‘evolution’ as represented by her grandfather. She overlooked, as Gould did not, the fact that the variations in the finches are in most cases minute, just as she overlooked the fact that, when he was labelling his finches as blackbirds and wrens, her grandfather was, in any case, a rather simple creationist with Paradise Lost in his pocket. She also overlooked another possible explanation for different varieties flourishing on different islands, namely that they had migrated from the South American mainland to environments which they found congenial, and that their evolution, if it occurred, might have owed nothing to the climate and conditions of the Galápagos at all. If further proof were needed that Darwin did not, at the time, see the significance of the Galápagos Islands’ biodiversity, one has only to think of the fate of the giant tortoises which he collected. Here indeed was evidence that, from island to island, there were differences between these fascinating and amiable creatures. Few as their descendants are today, we know that, as Nicholas Lawson observed, there were significant variations between the tortoises from one island and the next. This much Darwin noted, as the Beagle sailed away from the archipelago towards Tahiti, but he regarded the anomalies as ‘insignificant’ and, together with the officers at the Captain’s table, ate all the evidence and allowed the cook to dump even their carapaces overboard.81 This hardly suggests a scientific epiphany of the kind invented in the pious pages of Lady Barlow over a hundred years later.
If Darwin had not yet developed his theory of the origin of species by means of natural selection, this was not to say that no one else had done so. On 19 July, when the ship had anchored ‘in the outer part of the harbour of Callao’82 (the port for Lima), Darwin jotted in his notebook, ‘Smelling properties discussed of Carrion Crows, Hawks. Magazine of Natural History’.83 Clearly he had picked up a copy of the Magazine of Natural History which had been sent out by mail for Darwin from England. The reference to the ‘smelling properties of carrion crows, hawks’ refers to an article on this subject by Charles Waterton (and on the faculty of scent in the vulture) in the issues of January and May 1833.84
We do not know the exact point at which Darwin got hold of the issue of the Magazine of Natural History for January 1835, for this was the one which contained an article by Edward Blyth, expounding an evolutionary theory which Darwin would eventually appropriate and make famous.
It is a general law of nature for all creatures to propagate the like of themselves: and this extends even to the most trivial minutiae, to the slightest peculiarities; and thus, among ourselves, we see a family likeness transmitted from generation to generation. When two animals are matched together, each remarkable for a certain peculiarity, no matter how trivial, there is also a decided tendency in nature for that peculiarity to increase; and if the produce of these animals be set apart, and only those in which the same peculiarity is most apparent, be selected to breed from, the next generation will possess it in a still more remarkable degree; and so on, till at length the variety I designate a breed is formed, which may be very unlike the original type.
Just as Darwin would experiment with pigeons to see the ways in which species could adapt, from one sexual conjunction to the next, breeding characteristics which would be useful or strengthening, so Blyth asked whether the process we can watch at work in artificial breeding was not also at work in nature.
A variety of important considerations here crowd upon the mind, foremost of which is the enquiry, that, as man, by removing species from their appropriate haunts, superinduces changes on their physical constitution and adaptations, to what extent may not the same take place in wild nature, so that, in a few generations, distinctive characters may be acquired, such as are recognized as indicative of specific diversity . . . May not, then, a large proportion of what are considered species have descended from a common parentage?85
Having raised the idea, however, which would eventually be coterminous with Darwin’s name, Blyth rejected it, on the grounds that, ‘were this self-adapting system to prevail . . . we should seek in vain for those constant and invariable distinctions which are found to obtain’. In other words, he thought, if the theory were true, living species would blend into each other, which we can see is not the case in nature. Edward Blyth, a twenty-five-year-old pharmacist from the Surrey village of Tooting (now absorbed into the suburban sprawl of south London) was a poor man of no reputation.
In the ornithological notebooks which Darwin kept at the time, however, Barlow found reflections upon ‘Thenca (Mimus Thenca). These birds are closely allied in appearance to the Thenca of Chile . . .’ He recorded that he had collected different specimens from different islands, noting similarities and differences. ‘The only fact of a similar kind of which I am aware is the constant asserted difference between the wolf-like Fox of East and West Falkland Isds. – If there is the slightest foundation for these remarks, the Zoology of Archipelagoes will be well worth examining, for such facts would undermine the stability of species.’86
Barlow added, ‘It is astonishing, when we consider that more than twenty years were to elapse before this “undermining” of the stability of species was sufficiently documented to be given to the world in The Origin of Species.’87
A biography of Darwin must, chiefly, be the biography of an idea. This is Darwin’s idea, first published to the world in 1859, of what we now call evolution. He took some time to arrive at his conclusions, and he would then spend the rest of his life wrestling with them, and sometimes changing his mind about them. Some Darwin scholars question whether he had in fact read Blyth’s article in the Magazine of Natural History, even though he had plainly read another article in the same issue. This is in some senses of less significance than Darwin’s eventual conclusion about evolution.
Before proceeding, we should be clear in our minds what were the issues at stake for science here. There are three crucial points to master. First, is Blyth’s ‘were this self-adapting system to prevail . . . we should seek in vain for those constant and invariable distinctions which are found to obtain’. Biology proceeds on the basis that taxa are distinct. It is not simply a question of convenience to say this. Since Linnaeus – you could say since Aristotle and Pliny – it is a matter of actual observation, of what can be seen and tested. Comparative anatomy leads us to observe the phenomenon of what is called homology. A homologue is a constant. Take as an example the forelimbs of vertebrates. In The Origin of Species, Darwin would write,
What can be more curious than that the hand of man, formed for grasping, that of a mole for digging, the leg of a horse, the paddle of the porpoise, and the wing of the bat, should all be constructed on the same pattern, and should include similar bones, in the same relative positions?
We may call this conformity to type, without getting much nearer to an explanation of the phenomenon . . . but is it not powerfully suggestive of true relationships, of inheritance from a common ancestor?88
Here you have the essence of the puzzle, laid out in Darwin’s clear, good prose. In each case – horse, bat, man, mole, porpoise, etc. – we find the same basic building-blocks in the forelimbs – humerus, radius, ulna, carpals, metacarpals and phalanges. You find, to use anthropomorphic language, that they all, basically, have something equivalent to our upper
arm, our forearms, with its two bones radius and humerus, and they all have the five-fingered ‘hand’, which, in the case of the horse – for example – you can watch, through the gradations of fossil evidence, changing and adapting, never using its ‘thumb’ even when it was a little foxlike creature, and eventually encasing its ‘hand’ in a hoof.
That is the phenomenon. Blyth was not the first to see it. Cuvier had seen it. Lamarck had seen it. Goethe had seen it. Erasmus Darwin had seen it. Blyth was perhaps the first to spell out what it implied for taxonomy (that is, species classification) if you thought that one species evolved into another.
No serious observer of the fossil evidence, and of the bones dug up and studied by the palaeontologists, would question that we can observe a process of adaptation at work in nature. The basic building-blocks, the homologues, adapt themselves according to need, circumstance, environment.
The further question, however – and this is where Darwin would eventually become revolutionary – is whether these basic building-blocks themselves evolve, or whether they were simply given. We watch the five-fingered ‘hand’ changing in the evolutionary cycle of the mole, the porpoise, the bat, the horse, the man. Do we find any evidence that the hand itself, the five-fingered entity, had evolved?
That is a question which Darwin has to answer if we are to consider him the greatest revolutionary scientist of the nineteenth century, or merely a naturalist of genius, whose theory of how things came into being remains questionable. There is plenty of evidence for the building-blocks adapting themselves. But such things as hair, feathers, eyes or even hands – is there any evidence for these forms, often in themselves extremely complex, having ‘evolved’? Darwin had cottoned on to the process of micro-evolution (as with the finch-beaks) in some species and had made it into a universal. The same principle which accounts for the shape of a finch’s beak also accounts for the difference between a bee and an elephant.
And then again – and this is fundamental to the whole story – what do we mean by using this word ‘evolution’, which Darwin himself was slow to use, and which was certainly not current when he was aboard the Beagle? The word carries two connotations which we must hold in our heads for the rest of this story: what can be termed micro-evolution, and macro-evolution.
When John Gould, of the Ornithological Society of London, began to examine the finches which Darwin had sent home, he saw a process at work which we could usefully describe as micro-evolution. Little changes were occurring which made the beaks of the finches more useful for them in various particular environments. Now, Darwin is famous for the conclusion he reached, in The Origin of Species, that ultimately all life derives from a common source. Micro-evolution cannot be denied. Ever since the development of palaeontology and fossil study in the early nineteenth century, it has been possible to see, within species, the same basic homologues or building-blocks being adapted for different purposes.
Darwin was to develop the theory (with which Blyth in the Magazine of Natural History had only doodled) that all life-forms evolve in this gradual way. Just as the finches’ beaks changed little by little, so too all forms – including the basic building-blocks – came about by these infinitesimally gradual processes. Nature does not make leaps. This was to be Darwin’s central contention. Even forms which look as if they are highly complex – such as eyes, or hair, or feathers – slowly evolved. This we can call macro-evolution.
Some people, both during Darwin’s lifetime and since – have seen his ideas in a religious light, as he did himself. They think that if this version of evolution could be demonstrated, it would remove the need for belief in a Creator. To use the words of Darwin’s wife Emma Wedgwood, his ideas seemed to be ‘putting God further and further off’.89
If one leaves the religious question on one side, however, it might help to clear the mind for a consideration of the factual evidence. Evolution clearly takes place. The question which science would love to answer is – how? When Darwin had developed his theory, would nature provide him with evidence to prove it? Or would there remain an everlasting puzzle, at the apparent ‘leaps’ in the living world and its development? This really is the key question. From the beginnings of the idea that all life derives from one, or a few, simple sources, there have been religious believers who espoused it, and scientists who refused to believe it until the evidence was provided. This is our story, Darwin’s story. The biography of this idea is, in the end the story, not simply of one man, but of the Western world which came to believe that ‘what are considered species have descended from a common parentage. The microevolution of the finches was observable. The common ancestry of mammals is not. It is hardly surprising that Darwin, who always guarded his public reputation so carefully, should have waited before committing himself to the view that giraffes, elephants, blue whales and Queen Victoria herself all descended from a tiny animal a bit like a shrew.’90 It is indeed necessary to believe this if you accept Blyth’s ‘common parentage’ theory of the origin of species. Darwin would not go public with such a view until circumstances forced him into it.
When they left the Galápagos Islands, in October 1835, Darwin, in common with the majority of the officers and men, was ready for home. In fact, a year would pass before their Odyssey was done. They sailed through the South Pacific, as Cook had done in the 1770s, spending ten glorious days on Tahiti – ‘the Queen of the Islands’,91 Darwin called it. Darwin shared FitzRoy’s admiration for the missionaries there, who ‘have done much in improving’ the moral character of the natives. ‘It is something to boast of, that Europeans may here, amongst men who so lately were the most ferocious savages probably on the face of the earth, walk with as much safety as in England.’ George Forster’s descriptions of Tahiti, in his account of Cook’s visits, dwelt lovingly upon the beauties of the all but naked women who had swum out to the Resolution and offered themselves to the English sailors (a passage which James Boswell particularly savoured, to Johnson’s annoyance). Darwin, over sixty years later, by contrast, ‘was much disappointed in the personal appearance of the women; they are far inferior in every respect to the men’.92 He disliked their style of cutting their hair, ‘or rather shaving it from the upper part of the head in a circular manner so as only to leave an outer ring of hair’, and he found their tattoos unseemly. ‘They are in greater want of some becoming costume even than the men.’93
Were this entry written by a strict Christian like FitzRoy, or by a much older man, it might pass without remark. The man who wrote about the Tahitian women was not yet twenty-six years old. The sentence prompts the inevitable – if unanswerable – question of Darwin’s sexuality, and how this side of life was tackled during his years in South America. The diary gives no clue, and one gets no sense, when he visited Rio de Janeiro, Buenos Aires, Valparaiso or Lima, that he pursued women. The lack of evidence suggests either very great discretion or very great restraint; if the latter, it was perhaps more easily achieved in one with very low libido.94 Certainly, in Tahiti, where there would undoubtedly have been the opportunity to enjoy the women, we find him merely basking in the sunshine, enjoying the fruit (‘I do not know anything more delicious than the milk of a young Cocoa Nut’).95 And of course, short as his time was on Tahiti – just eleven days – he explored and botanized and mused on the origins of coral. The splendid Queen Pomare of Tahiti came on board the Beagle – ‘an awkquard [sic] large woman without any beauty, gracefulness or dignity of manners’.96
They got under way on 25 November and sailed to New Zealand, which they reached in three weeks. As they explored the Maori villages, Darwin was as shocked as FitzRoy by the heathenism. ‘This little village is the very stronghold of vice; although many tribes, in other parts, have embraced Christianity, here the greater part are yet remain [sic] in Heathenism.’ One can only conclude that the ‘vice’ here referred to is sexual. Certainly, on all Cook’s visits, the openness with which the Maori women greeted his crews was remarked upon in the normally broad-minded C
aptain’s journals. Darwin also found the Maoris dirty – ‘the idea of washing either their Persons or clothes never seems to have entered their heads’.97
Darwin attended divine service on Christmas morning ‘in the chapel of Pahia . . . So excellent is the Christian faith, that the outward conduct of the believers is said most decidedly to have been improved by its doctrines, which are to a certain extent generally known.’98
The New Zealanders in general failed to impress. Darwin came to the conclusion that ‘the whole population is addicted to drunkenness & all kinds of vice’.99 The native New Zealander compared ill with the Tahitian. ‘One glance at their respective expressions, brings conviction to the mind that one is a savage, the other a civilised man.’100 The English residents were, in Darwin’s view, ‘of the most worthless character . . . many of them run away convicts from New South Wales’.101 And it was to New South Wales, after Christmas, that the Beagle sailed.
They anchored within Sydney Cove, and he walked the new-built streets. Gigs, phaetons and carriages whizzed about this rapidly expanding city, whose population was 23,000. There was something in the air which was instantly familiar, and reassuring, to the banker-doctor’s son of Shrewsbury: money. Whereas in the South American cities the landed and propertied classes were ‘known’, here the new rich swanned about in their carriages, careless of whether or not they were of ‘known family’. He was in the land of Great Expectations. ‘An auctioneer who was a convict, it is said intends to return home & will take with him 100,000 pounds. Another who is always driving about in his carriage, has an income so large that scarcely anybody ventures to guess at it, the least assigned being fifteen thousand a year. But the two crowning facts are, first that the public revenue has increased 60,000 £ during this last year, & secondly that less than an acre of land within the town of Sydney sold for 8000 pounds sterling.’102 (Darwin’s father, when he died in 1848, left £223,759,103 and was one of the richest men in Shropshire.) Only fifteen years had elapsed, when Darwin reached Sydney, since the retirement of Lachlan Macquarie, the ‘father of Australia’, as Governor of New South Wales. It was Macquarie who ‘found a gaol, he left a burgeoning colony’.104 It was he – the child of a tenant farmer from the tiny Hebridean island of Ulva, who rose to be lieutenant-colonel in the 77th Highland Regiment – who had decided to transform Australia from a place which was primarily a penal colony into an incipient modern nation. Darwin saw an infant nation: the Australian Cricket Club had been formed in 1827. Each Sunday, the uniformed Governor would appear at St James’s Church, an emblematic assembly in which the left and centre aisles were packed with uniformed officers and rich merchants, and the right-hand gallery was full of convicts.105 It was Macquarie’s genius to pursue an ‘emancipationist’ policy, allowing the convicts in the right gallery to transmute, eventually, into the rich merchants in the centre aisle. Darwin, whose honest antecedents in Staffordshire had made comparable stratospheric leaps through the ranks, could not fail to be impressed.