by A. N. Wilson
Darwin was working in complete ignorance of what science would know as genetics. One reason, perhaps, for his failure to come anywhere near understanding the process of inheritance was that he was casting his net so wide, writing off to India to get Blyth’s views on every creature from ants to elephants, dissecting barnacles and insect-eating orchids and, of course, mixing with the pigeon-fanciers, whose genuine knowledge of their subject he lapped up. The result was that he assembled a collection of facts so enormous that it would have been hard to know where to focus. Although he believed there was one simple explanation for how inheritance works, he thought to test out the idea by a Humboldtian investigation of everything. Mendel stuck to peas and observed one simple process at work. The old saying about the hedgehog and the fox comes to mind. Having grasped the principle which was expounded by Mendel, it became possible, by the mid- to late twentieth century, for biology to see how densely complicated, how various, how simply massive is the amount of information stored, conveyed and passed on through the double helix, which ‘packs over a hundred trillion times as much information by volume as the most sophisticated computerized information system ever devised’.1
Mendel’s theory, confirmed by the genetic researches following Watson and Crick’s stupendous discovery of the double helix and its structure, is really lethal to Darwinism. As mentioned, by the beginning of the twentieth century, Mendel’s theory had been largely forgotten, and it was only when it was revived, and the science of modern genetics began, that some scientists devised what has been called neo-Darwinism, or a supposed synthesis between the two ideas – Mendel and Darwin, genetics and gradualism. In 1937, the experimental zoologist Theodosius Dobzhansky wrote Genetics and the Origin of Species in which he argued that it was possible to reconcile Darwinism, with its commitment to a gradualist evolution, and genetics, with its factual evidence that the gene is passed down like a hard, unvarying particle, like a piece of shot. His views were adopted by Thomas Huxley’s grandson Julian Huxley in his Evolution: The Modern Synthesis (1942). The ideas of this synthesis were applied to palaeontology by George Gaylord Simpson in Tempo and Mode in Evolution (1944). From these three books stem the fusion of Darwinian theory and genetic knowledge which is orthodoxy in most academic schools of biology and which has been popularized, for example, by Richard Dawkins. It attempts to blend population genetics with the old Darwinian doctrines: so we see randomly produced genetic variations helping individuals in a species population better adapted to compete for resources in their environment. The favourable genes are then, supposedly, inherited in greater numbers in the gene pool, the total number of genes in any particular species, until the new species emerges. The trouble with this is that mutations in genes tend not to be minor; nor are they obviously always to the advantage of a species – witness the many mutations responsible for diseases.
It has been suggested that Darwin owned a copy of Mendel’s paper. In Michael R. Rose’s Darwin’s Spectre it is stated that ‘an unopened copy of Mendel’s crucial paper on inheritance in peas was found among Darwin’s files after his death’.2 This, however, turns out not to be true. Investigations in the Cambridge University Library, where the bulk of the Darwin archive is stored, reveals no work by Mendel among Darwin’s books or papers, and Francis Darwin writing in More Letters of Charles Darwin says, ‘It is remarkable that, as far as we know, Darwin never in any way came across Mendel’s work.’3 Peter Gautrey, in his paper written with Robert Olby, ‘The Eleven References to Mendel before 1900’, points out that Darwin is known to have had copies of two works which did quote from Mendel’s paper.4 Darwin made a number of annotations in his copy of one of these, by Hermann Hoffmann, but not on the page which refers to Mendel; the other, Die Pflanzen-Mischlinge, by Wilhelm Olbers Focke, was acquired by Darwin in November 1880 but the pages which refer to Mendel’s work were never cut.
Darwin was aware, almost before the first edition of The Origin of Species had been published, that there was something defective about his inheritance theory.5 He devoted only one chapter of The Origin to the question, but he had accumulated so much material on the subject that it was his intention to work up at least three more chapters in a later book. And the book published as The Variation of Animals and Plants under Domestication represents his attempt to come to grips, not only with the critics of The Origins, but also with the core scientific problem of his book – a problem, incidentally, with which science had been wrestling certainly since 1799, when Thomas Andrew Knight published a paper for the Royal Society on . . . none other than that revealing genus the Pisum: a foreshadowing of Father Mendel in his monastery garden. Knight was more naturalist than theorist, so he observed how peas bred, and how hybridization affected them more than he asked why. Darwin, having come to see that variation was passed on, but having accepted (for some decades anyway) that Lamarck’s theory was wrong, had to find a way of explaining how variation was handed on from one generation to the next. Knight crossed grey peas with white peas and noted the phenomenon (though he did not call it that, of course) of the dominant gene. Only grey peas were produced. The white pea was recessive.6 Darwin supposed that when two parents mated, their characteristics were blended. Lyell, never fully a convert to Darwin’s idea of natural selection, had weighed the arguments, in Principles of Geology (volume two), in favour of the transmutation of species. ‘The entire variation from the original type, which any given kind of change can produce, may usually be effected in a brief period of time, after which no farther deviation can be obtained by continuing to alter the circumstances, though ever so gradually – indefinite divergence either in the way of improvement or deterioration, being prevented, and the least possible excess beyond the defined limits being fatal to the existence of the individual.’7
In Darwin’s copy of this book, he has underscored the words ‘improvement or deterioration’ and added, ‘If this were true, adios theory.’8
This was the point upon which Wilberforce seized, both in his speech at the BAAS in Oxford and in his thirty-page review of The Origin of Species. Had he limited himself to the discussion of variation in species, and avoided the cheap gag about Huxley’s grandmother, Wilberforce’s place as a footnote in the history of science would be more glorious. The same point was made by the Scottish engineer Fleeming Jenkin, in his review of the fourth edition of The Origin in a periodical called the North British Review, in 1867. Jenkin was taking a break from his work together with James Clerk Maxwell on the calibration of standard coils of wire, which would eventually perfect cable communications and regularize the use of telegraphy. He was, therefore, one of the real pioneers of the modern world, bringing to pass the marriage of technology and political expansionism which made Britain the predominant power during these decades.
Jenkin’s review was immensely long. Given its date – written just a decade after Mendel’s discovery – it is tantalizingly close to Mendel. He can see the problem which Mendel solved, without – of course – knowing the solution. ‘A given animal or plant appears to be contained as it were within a sphere of variation; one individual lies near one portion of the surface, another individual, of the same species, near another part of the surface; the average animal at the centre . . .’; Darwin envisaged a slow process of variation. But, said Jenkin – here following Wilberforce’s argument, and agreeing with what Agassiz also said – for Darwin’s theory to work it is necessary for time to ‘fix’ the variety. He imagined each species, or ur-species, in a ‘sphere’, and for Darwin’s theory to work variations within that sphere would have to get beyond its own limit. He acknowledged, as any countryman or rose-breeder or pigeon-fancier might do, that slight improvements might be discernible within a species. But there remained Wilberforce’s puzzle: how come artificial hybrids revert in the wild? Jenkin can see, in other words that there is a something which determines how species inherit their characteristics – what we know to be genes. Darwin could see it too, but he could not answer either Jenkin or Wilberforce or
Agassiz. ‘Fleeming Jenkin has given me much trouble, but has been of more real use to me that any other essay or review.’9 If he could not answer Jenkin, it did look very much as if he would, after thirty years’ work, be obliged to say adios, theory.
Hooker, such a kind friend to Darwin and such a conscientious scientist, could see that the theory on which Darwin’s reputation was based was a theory of variation: how are variations passed on through inheritance? And do such variations account for the ‘origin’ of species – that is, do species evolve from variations into other species? In 1862, he and Darwin had exchanged letters on the subject, and Darwin had written that he had, in effect, moved back to the position of Lamarck. ‘I hardly know why I am a little sorry but my present work is leading me to believe rather more in the direct action of physical conditions. I presume I regret it, because it lessens the glory of Natural Selection, and is so confoundedly doubtful. Perhaps I shall change again when I get all my facts under one point of view, and a pretty hard job this will be.’10
Hooker, six years later, broke it to Darwin that he was going to devote his Presidential Address at the BAAS to ‘the fact that Darwin’s theory had failed’.11 (So much for the ‘victory’ of Huxley in the 1860 debate!) Darwin’s crestfallen reply is painfully revealing, since it suggests that – at the time of writing at least – he had abandoned the theory in favour of Lamarckianism. He was saying that the Origin triumph was not that it was true in detail, but that it made people believe in evolution in general.
I am glad to hear that you are going to touch on the statement that the belief in Natural Selection is passing away. I do not suppose that even the Athenaeum would pretend that the belief in the common descent of species is passing away, and this is the more important point. This now almost universal belief in the evolution (somehow) of species, I think may be attributed in large part to the Origin . . . If you agree about the non-acceptance of Natural Selection, it seems to me a very striking fact that the Newtonian theory of gravitation, which seems to everyone now so certain and plain, was rejected by a man so extraordinarily able as Leibnitz. The truth will not penetrate a preoccupied mind.12
This is a sad letter not merely because he sees a trusted friend publicly disputing his theory, but because, in the space of only a few sentences, he appears to be saying two quite contradictory things. First, he says that the theory of natural selection is not true, but that at least it made people believe in ‘the evolution (somehow) of species’. Then, appalled by the thought of saying adios to his theory, he compares it, not for the first time, to the discovery by Newton of how the universe holds together by gravitational force.
Darwin felt isolated. Wallace had returned to Britain in 1862, his own health – though not as poor as Darwin’s – badly diminished by living in the Malayan Archipelago. Wallace was taken up by Huxley, and introduced to Lyell’s rather grand drawing-room. But salon-life was not for him, and this wraith-like, gentle, bearded man felt out of his depth in London society. He made visits to Down, but there was an awkwardness about the relationship between the two discoverers of natural selection. Wallace remained firm in his faith in the theory. He was a purer ‘Darwinian’ in this sense than Darwin. The Duke of Argyll, who would be Secretary for India in Gladstone’s first government, wrote a review of Darwin’s orchid book, maintaining the Sherlock Holmes argument that these flowers showed the Creator’s hand, creating beauty for beauty’s sake. The Duke followed it up with a book of his own, The Reign of Law (1867), in which he developed his theme: ‘Ornament or beauty is in itself a purpose, an object, an end.’ He cited the hummingbird with its topaz crest. This, surely, was an example of beauty having been created for its own sake? Darwin amazed Huxley by being rather impressed by this argument. He was shocked by Huxley’s perky class chippiness in calling the Duke ‘the Dukelet’ and the ‘little beggar’. ‘I have always thought the D. of Argyll wonderfully clever,’ Darwin countered. ‘As for calling him a little beggar, my inherited instinctive feelings wd. declare it was a sin thus so speak of a real old Duke.’13 His own view of how the hummingbird got its crest began to modify. ‘Natural’ selection was not sufficient to explain so extravagant a manifestation. Sexual selection was more to the point. Wallace urged Darwin simply to stick to his guns.
The combination of ducal piety on the one hand and the scientific rigour of Jenkin on the other forced Darwin to come up with some ‘it’, some phenomenon which could explain how variation was passed down through the processes of inheritance. He could see, in other words, the hole in the story, which we can see being filled by Mendel’s genetics. Not knowing the Mendelian solution – and, so frustratingly for us, it was sitting there, waiting for Darwin to read about it, in an article which he possessed but did not read! – Darwin came up with an explanation which was simply wrong. He called his mysterious X, his explanation, ‘pangenesis’. The science of genetics, as pioneered by Mendel and expanded since the discovery of the double helix, does not require, even in the metaphorical sense used by Darwinians, any motivation as an explanation of why some forms are handed down. What genetics reveal is how the process works. Darwin could see characteristics being handed on, by orchids, by pigeons, by members of the Darwin family – for the illnesses which beset his children in the nursery all tormented him, not only as a parent, but as a scientist who feared that he and Emma had bred too many of their neurotic family ailments. Pangenesis was a rather feeble combination of Lamarck and his own musings. He proposed that every tissue, cell and living part of an organism produced unseen germs, gemmules or granules which carried on inheritable characteristics. There were gemmules which decided the size or shape of your feet, the colour of your hair, and so forth. These characteristics were, he believed, mixed up by sexual congress. For Darwin, the granules, or whatever they were, were a sort of melange produced by sex; but also – and here he added a dash of Lamarck to his rather desperate concoction – some limited effects from the environment were embedded in each individual’s constitution, and could be handed on to the offspring, through the gemmules. Wallace urged him to stick, simply, to the idea of natural selection – as the majority of Darwinists do in our own day. When Huxley first read Darwin’s attempt to articulate pangenesis, he playfully said that he had donned his ‘sharpest spectacles and best thinking cap’. ‘Somebody rummaging among your papers half a century hence will find Pangenesis and say, “See this wonderful anticipation of our modern theories and that stupid ass Huxley prevented his publishing them”.’14 It was Huxley’s kind way of telling him not to publish the pangenesis idea. The advice was not heeded.
Someone who came much closer to a Mendelian solution of the problem of inheritance was a writer who was not in the narrow sense of the word a scientist at all – Herbert Spencer.
Just as, during the evolution of an organism, the physiological units derived from the two parents tend to segregate, and produce likeness to the male parent in this part and to the female parent in that: so, during the formation of reproductive cells, there will arise in one a predominance of the physiological units derived from the father, and in another a predominance of the physiological units derived from the mother. Thus, then, every fertilized germ, besides containing different amounts of the two parental influences, will contain different kinds of influences – this having received a marked impress from one grandparent, and that from another. Without further exposition the reader will see how this cause of complication, running back through each line of ancestry, must produce in every germ numerous minute differences among the units . . .
From the general law of probabilities it may be concluded that while these involved influences, derived from many progenitors, must, on the average of cases, obscure and partially neutralize one another; there must occasionally result such combinations of them as will produce very marked divergences. There is thus a correspondence between the inferable results and the results as habitually witnessed.15
The Danish biologist Søren Løvtrup, citing this passage, adds,
‘Evidently, Spencer was a Micromutationist insisting on the necessity of macromutations, which he assumed to arise through particular combinations of micromutations. Surely, if Darwin had paid a little more heed to Spencer, he could have saved himself much trouble.’16
When Spencer met Darwin, before the publication of The Origin, and heard what the theory was, he quipped that it might well be termed ‘the survival of the fittest’ – a tag which Darwin adopted, and which stuck. Spencer was eleven years younger than Darwin. Like any human being, Darwin found Spencer’s voluminous writings hard going. ‘His conclusions never convince me: and over and over again I have said to myself, after reading one of his discussions – “Here would be a fine subject for half-a-dozen years’ work.”’17 On other occasions, however, he deemed Spencer ‘wonderfully clever, and I dare say mostly true’ (1866 to Hooker), and by the end of the decade he even suspected ‘that hereafter he will be looked at as by far the greatest philosopher in England; perhaps equal to any that have lived’ (1870 to E. R. Lankaster).18
Every now and then there is a brave attempt by an academic to remind us of Spencer’s very existence.19 He has largely evaporated from the consciousness of thinking or reading people. Whereas some in the twenty-first century have read Carlyle – and many have read Darwin, Newman, Mill – Spencer is, of all the nineteenth-century British intellectuals, the one whose significance has been most utterly lost. It is easy to mock him.20 His hypochondria alone was far more absurd than Darwin’s: his insistence, for example, upon taking his pulse at particular times of day and, if the pulse rate was too fast, turning at once for home; his refusal to wear conventional dress (caps rather than silk hats, no evening clothes – though he relaxed this rule when invited to dine with Monckton Milnes – Lord Houghton – to meet the King of the Belgians); his ‘love affair’ with George Eliot, which was never consummated; and the sheer volume of what he wrote – A System of Synthetic Philosophy (1860), First Principles (1862), The Principles of Biology (two volumes, 1864–7), The Principles of Psychology (1870–2), The Principles of Sociology (1876–96), The Data of Ethics (1879), not to mention the thousand-page autobiography. He was probably the most famous ‘philosopher’ of the day, easily as famous as in their day Sartre or Lévi-Strauss. When he died, the Italian parliament observed a minute’s silence. They did not go quite so far in the US Congress, but he was hugely revered in America, where audiences put up with his strange habit of accepting engagements and then refusing to speak to them. It was enough to see the Master. His works were translated into languages as different as Chinese and Mohawk. Progressive-minded Indians absorbed him, as did the French and the Germans.