Charles Darwin. Allen Grant

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СКАЧАТЬ in Madeira was pointing out the strange adaptations of the curious local snails and beetles. Von Buch in the Canaries was coming to the conclusion that varieties may be slowly changed into permanent species. Lecoq and Von Baer were gradually arriving, one by the botanical route, the other by the embryological, at the same opinion. Before Charles Darwin was twenty, Dean Herbert had declared from the profound depth of his horticultural knowledge that kinds were only mere fixed sports; and Patrick Matthew, in the appendix to a work on 'Naval Timber,' had casually developed, without perceiving its importance, the actual distinctive Darwinian doctrine of natural selection. Robert Chambers published in 1844 his 'Vestiges of Creation,' in which Lamarck's theory was impressed and popularised under a somewhat spoilt and mistaken form: it was not till 1859 that the first edition of the 'Origin of Species' burst like a thunderbolt upon the astonished world of unprepared and unscientific thinkers.

      This general attitude of interest and inquiry is of deep importance to the proper comprehension of Charles Darwin's life and work, and that for two distinct reasons. In the first place, the universal stir and deep prying into evolutionary questions which everywhere existed among scientific men in his early days was naturally communicated to a lad born of a scientific family, and inheriting directly in blood and bone the biological tastes and tendencies of Erasmus Darwin. In the second place, the existence of such a deep and wide-spread curiosity as to ultimate origins, and the common prevalence of profound uniformitarian and evolutionary views among philosophers and thinkers, made the acceptance of Charles Darwin's particular theory, when it at last arrived, a comparatively easy and certain matter, because by it the course of organic development was assimilated, on credible grounds, to the course of all other development in general, as then already widely recognised. The first consideration helps us to account in part for the man himself; the second consideration helps us even more to account for the great work which he was enabled in the end so successfully to accomplish.

      CHAPTER II

      CHARLES DARWIN AND HIS ANTECEDENTS

      From the environment let us turn to the individual; from the world in which the man moved to the man who moved in it, and was in time destined to move it.

      Who was he, and whence did he derive his exceptional energy and intellectual panoply?

      Erasmus Darwin, the grandfather, the first of the line in whom the distinctive Darwinian strain of intellect overtly displayed itself, was the son of one Robert Darwin, a gentleman of Nottinghamshire, 'a person of curiosity,' with 'a taste for literature and science;' so that for four generations at least, in the paternal line, the peculiar talents of the Darwin family had been highly cultivated in either direction. Robert Darwin was an early member of the Spalding Club, a friend of Stukeley the antiquary, and an embryo geologist, after the fantastic, half-superstitious fashion of his own time. Of his four sons, both Robert, the eldest, and Erasmus, the youngest, were authors and botanists. Erasmus himself was a Cambridge man, and his natural bent of mind and energy led him irresistibly on to the study of medicine. Taking his medical degree at his own university, and afterwards preparing for practice by attending Hunter's lectures in London, besides going through the regular medical course at Edinburgh, the young doctor finally settled down as a physician at Nottingham, whence shortly afterward he removed to Lichfield, then the centre of a famous literary coterie. So large a part of Charles Darwin's remarkable idiosyncrasy was derived by heredity from his paternal grandfather, that it may be worth while to dwell a little here in passing on the character and career of this brilliant precursor of the great evolutionist. Both in the physical and in the spiritual sense, Erasmus Darwin was one among the truest and most genuine ancestors of his grandson Charles.

      A powerful, robust, athletic man, in florid health and of temperate habits, yet with the full-blooded tendency of the eighteenth century vividly displayed in his ample face and broad features, Erasmus Darwin bubbled over with irrepressible vivacity, the outward and visible sign of that overflowing energy which forms everywhere one of the most marked determining conditions of high genius. Strong in body and strong in mind, a teetotaler before teetotalism, an abolitionist before the anti-slavery movement, he had a great contempt for weaknesses and prejudices of every sort, and he rose far superior to the age in which he lived in breadth of view and freedom from preconceptions. The eighteenth century considered him, in its cautious, cut-and-dried fashion, a man of singular talent but of remarkably eccentric and unsafe opinions. Unfortunately for his lasting fame, Dr. Darwin was much given to writing poetry; and this poetry, though as ingenious as everything else he did, had a certain false gallop of verse about it which has doomed it to become since Canning's parody a sort of warning beacon against the worst faults of the post-Augustan decadence in the ten-syllabled metre. Nobody now reads the 'Botanic Garden' except either to laugh at its exquisite extravagances, or to wonder at the queer tinsel glitter of its occasional clever rhetorical rhapsodies.

      But in his alternative character of philosophic biologist, rejected by the age which swallowed his poetry all applausive, Erasmus Darwin is well worthy of the highest and deepest respect, as a prime founder and early prophet of the evolutionary system. His 'Zoonomia,' 'which, though ingenious, is built upon the most absurd hypothesis' – as men still said only thirty years ago – contains in the germ the whole theory of organic development as understood up to the very moment of the publication of the 'Origin of Species.' In it Dr. Darwin calls attention to 'the great changes introduced into various animals by artificial or accidental cultivation,' a subject afterwards fully elucidated by his greater grandson in his work on 'The Variation of Animals and Plants under Domestication.' He specially notes 'the immense changes of shape and colour' produced by man in rabbits and pigeons, the very species on which Charles Darwin subsequently made some of his most remarkable and interesting observations. More than any previous writer, Erasmus Darwin, with 'prophetic sagacity,' insisted strongly on the essential unity of parent and offspring – a truth which lies at the very base of all modern philosophical biology. 'Owing to the imperfection of language,' wrote the Lichfield doctor nearly a hundred years ago, 'the offspring is termed a new animal, but is in truth a branch or elongation of the parent, since a part of the embryon-animal is or was a part of the parent, and therefore may retain some of the habits of the parent system.' He laid peculiar stress upon the hereditary nature of some acquired properties, such as the muscles of dancers or jugglers, and the diseases incidental to special occupations. Nay, he even anticipated his great descendant in pointing out that varieties are often produced at first as mere 'sports' or accidental variations, as in the case of six-fingered men, five-clawed fowls, or extra-toed cats, and are afterwards handed down by heredity to succeeding generations. Charles Darwin would have added that if these new stray peculiarities happened to prove advantageous to the species they would be naturally favoured in the struggle for existence, while if they proved disadvantageous, or even neutral, they would die out at once or be bred out in the course of a few crosses. That last truth of natural selection was the only cardinal one in the evolutionary system on which Erasmus Darwin did not actually forestall his more famous and greater namesake. For its full perception, the discovery of Malthus had to be collated with the speculations of Buffon.

      'When we revolve in our minds,' says the eighteenth century prophet of evolution, 'the great similarity of structure which obtains in all the warm-blooded animals, as well quadrupeds, birds, and amphibious animals, as in mankind; from the mouse and bat to the elephant and whale; one is led to conclude that they have alike been produced from a similar living filament. In some this filament in its advance to maturity has acquired hands and fingers with a fine sense of touch, as in mankind. In others it has acquired claws or talons, as in tigers and eagles. In others, toes with an intervening web or membrane, as in seals and geese. In others it has acquired cloven hoofs, as in cows and swine; and whole hoofs in others, as in the horse: while in the bird kind this original living filament has put forth wings instead of arms or legs, and feathers instead of hair.' This is a very crude form of evolutionism indeed, but it is leading up by gradual stages to the finished and all-sided philosophy of physical life, which at last definitely formulates itself through the mouth of Charles Darwin. We shall see hereafter wherein Erasmus Darwin's conception of development chiefly failed – in attributing evolution for the most part to the exertions and endeavours of the animal itself, rather than to inevitable survival СКАЧАТЬ