Charles Darwin

by Andrew Norman

  Natural selection

  According to Darwin ‘species have generally originated by the natural selection of extremely slight differences’,21 and

  each slight modification of structure which was in any way beneficial under excessively complex conditions of life has been preserved, whilst each which was in any way injurious has been rigorously destroyed. And the long-continued accumulation of beneficial variations will infallibly have led to structures as diversified, as beautifully adapted for various purposes and as excellently co-ordinated, as we see in the animals and plants around us.22

  This, in a nutshell, summarized what was at the heart of Darwin’s great theory, and it was this that marked him out (along with Wallace) as one of the greatest original thinkers of all time.

  However, said Darwin, some naturalists ‘will never admit that one natural species has given birth to another until they behold all the transitional steps’.23

  The selective breeding of animals under domestication

  Animals that he included in his study were dogs, cats, horses, asses, pigs, cattle, sheep, goats, rabbits, pigeons, fowl, ducks, geese, peacocks, turkeys, guinea fowl, canaries, goldfish, bees, and moths.

  Although man does not cause variability and cannot even prevent it, he can select, preserve, and accumulate the variations given to him by the hand of nature almost in any way which he chooses; and thus he can certainly produce a great result.24 It can … be clearly shown that man …, by preserving in each successive generation the individual [animal or plant] which he prizes most, and by destroying the worthless individuals, slowly, though surely, induces great changes.25

  On the practical and proactive side, wrote Darwin,

  When a man attends rather more closely than is usual to the breeding of his animals, he is almost sure to improve them to a slight extent.26 [However] as a consequence of continued variability, and more especially of reversion, all highly improved races, if neglected or not subjected to incessant selection, soon degenerate.27

  Darwin gave as examples of species that could be ‘improved’: the racehorse, in terms of its fleetness; and livestock, in order to produce prize cattle and sheep. He concluded, ‘There can be no doubt that methodical selection has effected and will effect wonderful results.’28 But, he asked, was there any limit as to the ‘amount of variation in any part or quality’ which could be achieved? For instance, was it possible to produce gooseberries of ever-increasing weight; beetroot which yielded ‘a greater percentage of sugar’; or wheat and other types of grain, which ‘produce heavier crops than our present varieties’?29 With an ever-increasing world population these branches of science are, of course, of even greater relevance today.

  Man

  Finally, in the chapter entitled ‘Inheritance’, Darwin turned his attention to mankind, but not in the great detail which the world had hoped for and anticipated of him. Instead, he was content to observe that in human beings, disorders such as insanity, epilepsy, myopia, squint, hypermetropia, and polydactylism (the presence of supernumerary fingers and/or toes) were sometimes inherited. However, not all inherited characteristics were ‘evil’, and it was ‘fortunate that good health, vigour, and longevity are equally inherited’.30

  Pangenesis

  In an attempt to explain the phenomenon of variation/variability, Darwin put forward the theory of pangenesis. This, however, was not a new theory for, as he himself admitted, ‘views in many respects similar’ to his had previously ‘been propounded by various authors’.31

  The theory of pangenesis stipulates that ‘every separate unit or cell of an organism reproduces itself by contributing its share to the germ or bud of the future off-spring’.32 According to Darwin, pangenesis worked in the following way:

  i) Reproduction

  ovules, spermatozoa, and pollen grains, the fertilized egg or seed, as well as buds, include and consist of a multitude of germs thrown off from each separate part or unit [of the body].33

  These germs he called ‘gemmules … the number and minuteness of which must be something inconceivable’.34 Gemmules

  are dispersed throughout the whole system [of the living organism, and] when supplied with proper nutriment, [they] multiply by self-division, and are ultimately developed into units like those from which they were originally derived. They are collected from all parts of the system to constitute the sexual elements, and their development in the next generation forms a new being … . Hence, it is not the reproductive organs or buds which generate new organisms, but the units of which each [parent] individual is composed.35

  ii) Variation

  When two forms are crossed, one is not rarely found to be prepotent in the transmission of its characters over the other; and this we can explain by assuming … that the one form has some advantage over the other in the number, vigour, or affinity of its gemmules.36

  iii) Divergence

  The crossing of distinct forms, which have already become variable, increase in the offspring the tendency to further variability by the unequal commingling of the characters of the two parents, by the reappearance of long-lost characters, and by the appearance of absolutely new characters.37

  iv) Healing

  Referring to the healing process, Darwin declared that it was impossible to decide ‘whether the ordinary wear and tear of the tissues is made good by means of gemmules, or merely by the proliferation of pre-existing cells’.38

  v)

  Rudimentary or ‘vestigial’ organs (i.e. those which may have once had a purpose but now no longer do so).

  Darwin declared that ‘gemmules derived from reduced and useless parts would be more likely to perish than those freshly derived from other parts which are still in full functional activity’.39

  vi) Reversion

  Darwin postulated that ‘all organic beings … include [i.e. contain] many dormant gemmules derived from their grandparents and more remote progenitors, but not from all their progenitors’.40 ‘Reversion depends on the transmission from the forefather to his descendants of dormant gemmules, which occasionally become developed under certain known or unknown conditions.’41

  Here Darwin is attempting to explain the commonly observed phenomenon that certain characteristics may skip one or more generations, only to reappear at a later stage.

  vii) Inherited disease

  Each animal or plant may be compared with a bed of soil full of seeds, some of which soon germinate, some lie dormant for a period, whilst others perish. When we hear it said that a man carries in his constitution the seeds of an inherited disease, there is much truth in the expression.42

  Here, Darwin appears to be making an analogy between seeds and gemmules.

  In contrast to the theory of evolution, as propounded jointly by Darwin and Wallace, the theory of pangenesis lapsed into obscurity and was eventually forgotten. The science of the time was not sufficiently advanced for it to be proved or disproved, and when scientific knowledge did progress, the ‘gemmule’ was found to be nothing more than an imaginary concept, with no basis in reality. However, Darwin must be applauded for highlighting those aspects of reproduction, inheritance, and the capacity of the body to heal, for which there was, as yet, no explanation.

  * * *

  To physician and naturalist William Ogle, Darwin wrote on 6 March 1868 to say:

  I thank you most sincerely for your letter which is very interesting to me. [This letter has not been traced] I wish I had known of these views of Hippocrates before I had published [Variation], for they seem almost identical with mine … . The whole case is a good illustration of how rarely anything is new. The notion of pangenesis has been a wonderful relief to my mind, for during long years I could not conceive any possible explanation of inheritance, of development &c &c, or understand in the least in what reproduction by seeds & buds consisted.43

  This was a reference to Greek physician Hippocrates (c.460-c.377BC), who

  propounded a theory according to which minute particles from every part of
the body entered the seminal substance [or, in modern parlance, the spermatozoa and ovules] of the parents, and by their fusion gave rise to a new individual exhibiting the traits of both of them.44

  To Julius V. Carus, German comparative anatomist, Darwin wrote on 21 March 1868 to say, in respect of the theory of pangenesis:

  All cases of inheritance & reversion & development now appear to me under a new light; whether this is false or true.45

  In other words, Darwin was aware that his pangenesis theory was just a theory and not a scientific fact.

  * * *

  In that year of 1868 the indefatigable Darwin was to be found researching for another book which would be entitled The Descent of Man, and Selection in Relation to Sex and to this end, on 18 March, he wrote to entomologist Henry W. Bates, as follows:

  It has occurred to me that you must occasionally come across Missionaries or dealers [traders] who have long lived intimately with Savages; in this case, if you can, oblige me by leading conversation [i.e. let me know your views as] to the notion of savages about the beauty of women, & secondly & more especially how far the women have any indirect influence in getting men, whom they prefer or admire, to court them or purchase them from their parents.46

  In other words Darwin wished to know what factors in male and female ‘savages’ influence their choice of mate.

  On 18 April Darwin wrote to John J. Weir to say, in respect of his friend and colleague Alfred Russel Wallace, ‘I always distrust myself when I differ from him ….’47

  Hooker informed Darwin on 16 June that he had attended the fifth triennial festival in honour of George Frideric Handel at London’s Crystal Palace, where he had heard a performance of the composer’s oratorio ‘Messiah’.48 To this, Darwin replied on 17 June:

  I am glad you were at the Messiah: it is the one thing that I shd like to hear again, but I daresay I shd find my soul too dried up to appreciate it, as in old days; & then I shd feel very flat, for it is a horrid bore to feel, as I constantly do, that I am a withered leaf for every subject except science. It sometimes makes me hate science, though God knows I ought to be thankful for such a perennial interest which makes me forget for some hours every day my accursed stomach.49

  Here was an indication that Darwin was suffering from a chronic medical condition, the nature of which will be discussed shortly.

  Wallace wrote to Darwin on 30 August to say of his [Wallace’s] attendance at a recent meeting of the British Association for the Advancement of Science, held in Norwich, ‘Darwinianism was in the ascendant at Norwich; (I hope you do not dislike the word, for we really must use it,) … .’50

  In early 1869 Darwin was busy preparing a new edition of Origin. That October he wrote to the US natural historian James Orton to say, ‘Although I have never had any quarrel with Prof. [Richard] Owen, he has used such language about me that I can hold no communication with him.’51

  NOTES

  1. Darwin, Charles, The Variation of Animals and Plants under Domestication, Volume I, p.1.

  2. Ibid, Volume I, pp.8–9.

  3. Ibid, Volume I, p.8.

  4. Ibid, Volume II, p.271.

  5. Oxford Dictionaries Online.

  6. Darwin, Variation, Volume II, p.319.

  7. Ibid, Volume II, p.509.

  8. Ibid, Volume II, p.478.

  9. Ibid, Volume I, pp.343–4.

  10. Darwin to Wallace, 22 November, Cor. 18, p.303.

  11. Ibid, Volume I, p.353.

  12. Oxford Dictionaries Online.

  13. Darwin, Variation, Volume I, p.360.

  14. Ibid, Volume II, pp.484, 509.

  15. Darwin to St G.J. Mivert, Cor.19, p.34.

  16. Darwin, Variation, Volume II, p.199.

  17. Oxford Dictionaries Online.

  18. Darwin, Variation, Volume II, op. cit., p.70.

  19. Ibid, Volume II, p.432.

  20. Ibid, p.3.

  21. Ibid, p.504.

  22. Ibid, Volume II, pp.523–4.

  23. Ibid, Volume II, p.508.

  24. Ibid, Volume I, p.2.

  25. Ibid, Volume I, p.3.

  26. Ibid, Volume II, p.285.

  27. Ibid, Volume II, p.278.

  28. Ibid, Volume II, p.288.

  29. Ibid, Volume II, p.282.

  30. Ibid, Volume I, p.349.

  31. Ibid, Volume II, p.457.

  32. Simpson, J. A. and E. S. C. Weiner, The Oxford English Dictionary.

  33. Darwin, Variation, Volume II, op. cit., p.433.

  34. Ibid, Volume II, p.461.

  35. Ibid, Volume II, p.459.

  36. Darwin, Variation, Volume II, p.471.

  37. Ibid, Volume II, p.320.

  38. Ibid, Volume II, p.464.

  39. Ibid, Volume II, p.484.

  40. Ibid, Volume II, p.489.

  41. Ibid, Volume II, p.491.

  42. Ibid, Volume II, p.491.

  43. Darwin to William Ogle, 6 March, The Correspondence of Charles Darwin: Volume 16, 1868, pp.244–5.

  44. Orel, Heredity before Mendel

  45. Darwin to Carus, 21 March, Cor.16, p.288.

  46. Darwin to H. W. Bates, 18 March, Cor.16, p.279.

  47. Darwin to J. J. Weir, 18 April, Cor.16, p.413.

  48. J. D. Hooker to Darwin, 16 June 1868, Cor.16, p.583.

  49. Darwin to J. D. Hooker, 17, Cor.16, p.584.

  50. A. R. Wallace to Darwin, 30 August, Cor.16, p.705.

  51. Darwin to James Orton, 7 October, The Correspondence of Charles Darwin: Volume 17, 1869, p.420.

  Chapter 20

  Sir Francis Galton

  Francis Galton, anthropologist, explorer, and geographer, born in 1822, was the son of Samuel T. Galton (a banker), and Frances A. V. Galton (née Darwin). He and Darwin, both being grandsons of Erasmus Darwin, Charles as a result of Erasmus’s first marriage to Mary, and Francis as a result of Erasmus’s second marriage to Elizabeth, were, therefore, half-cousins.

  Galton’s Hereditary Genius: an Enquiry into its Laws and Consequences was published in 1869, a decade after Darwin’s The Origin of Species. By conducting genealogical research into ‘no less than 300 families containing between them nearly 1,000 eminent men …’,1 Galton, in his words, had endeavoured to find evidence of ‘hereditary genius’. These families he divided into groups, which included judges, statesmen, peers of the realm, military commanders, literary men, men of science, poets, musicians, ‘divines’ (senior clerics), senior classicists from Cambridge University, oarsmen, and wrestlers. Then, using a sliding scale, he classified the individuals in various groups ‘according to their natural gifts’. His conclusions were as follows:

  i. The nearer kinsmen of the eminent Statesmen were far more rich in ability than the more remote.2 [This also applied to judges.]

  ii. More than one half of the great literary men … had kinsmen of high ability.3

  iii. At least 40 per cent of the [fifty-six] Poets [in the survey] … had eminently gifted relations.4

  iv. Of the twenty-six musicians whom he studied about 1 in 5 … had eminent kinsmen…5

  v. Of the forty-two illustrious ancient painters [whom he studied, about half of them he described as] possessing eminent relations.6

  However, instead of using objective criteria for assessing the abilities of members of the various groups, Galton assumed that their rank alone was sufficient proof of their prowess. For example, of judges he asserted that ‘the office of a judge is really a sufficient guarantee that its possessor is exceptionally gifted’.7 As for statesmen, he declared that ‘as is the case in every other profession, none, except those who are extraordinarily and peculiarly gifted, are likely to succeed in parliamentary life …’.8

  When he came to compare ‘the worth of different races’, Galton concluded that ‘the number among the negroes of those whom we should call half-witted men, is very large.’ ‘The Australian type [i.e. the Aboriginal] is at least one grade below the African negro. The average standard of the Lowland [Scottish] and the English North-country
men is decidedly a fraction of a grade superior to that of the ordinary English … .’ However, ‘The ablest race of whom history bears record is unquestionably the ancient Greek … .’9 ‘If we could raise the average standard of our race [presumably the English or the British] by only one grade, what vast changes would be produced!’10

  However, the following passage by Galton appears to indicate that he laments the destruction of the weaker races.

  The number of the races of mankind that have been entirely destroyed under the pressure of the requirements of an incoming civilization, reads us a terrible lesson. Probably in no former period of the world has the destruction of the races of any animal whatever been effected over such wide areas and with such startling rapidity as in the case of savage man. In the North American Continent, in the West Indian Islands, in the Cape of Good Hope, in Australia, New Zealand, and Van Diemen’s Land, the human denizens of vast regions have been entirely swept away in the short space of three centuries, less by the pressure of a stronger race than through the influence of a civilization they were incapable of supporting.11

  But he goes on to argue that, for a variety of reasons, the ‘savage’ is incapable of being civilized.

  There is a most unusual unanimity in respect to the causes of incapacity of savages for civilization, among writers on those hunting and migratory nations who are brought into contact with advancing colonization, and perish, as they invariably do, by the contact. They tell us that the labour of such men is neither constant nor steady; that the love of a wandering, independent life prevents their settling anywhere to work, except for a short time, when urged by want and encouraged by kind treatment.12

  Much more alien to the genius of an enlightened civilization than the nomadic habit is the impulsive and uncontrolled nature of the savage. A civilized man must bear and forbear, he must keep before his mind the claims of the morrow as clearly as those of the passing minute; of the absent, as well as of the present. This is the most trying of the new conditions imposed on man by civilization, and the one that makes it hopeless for any but exceptional natures among savages to live under them. The instinct of a savage is admirably consonant with the needs of savage life; everyday he is in danger through transient causes; he lives from hand to mouth, in the hour and for the hour, without care for the past or forethought for the future: but such an instinct is utterly at fault in civilized life.13