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A331
Book:
Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.
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'mutations', as supplying the material for evolution. Writing to Asa Gray as early as August 11, 1860, he said of great and sudden variation:— 'I have, of course, no objection to this, indeed it would be a great aid, but I did not allude to the subject, for, after much labour, I could find nothing which satisfied me of the probability of such occurrences, There seems to me in almost every case too much, too complex, and too beautiful adaptation, in every structure to believe in its sudden production.1'
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A331
Book:
Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.
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When did Darwin acknowledge his debt in this way? It was on Aug. 29th, 1844. In 1842 he had written the first brief account of his theory of evolution—that sketch which will now be for the first time in the hands of the public—that sketch of which, thanks to your generosity, a gift has been made to every guest whom you are welcoming to Cambridge, a work which I for my part look forward to reading with greater pleasure and greater interest than any book I have ever possessed. In 1844 Darwin had
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A331
Book:
Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.
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APPENDIX B DARWIN AND EVOLUTION BY MUTATION I HAVE spoken on pages 43 and 44 of the frequency with which Darwin, between 1860 and 1880, was brought back by others to a motive cause of evolution based on 'sudden jumps', or 'monstrosities', on 'large', 'extreme', and 'great and sudden' variations. Such views were continually urged upon him by' his correspondents, and by reviews and criticisms of his work'. It is I think of interest, in relation to the biological fashions of the day, to show by
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A331
Book:
Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.
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Fluctuations are, according to de Vries, unable, however rigidly and however long selected, to lead to progressive evolution. The following passages in which this belief is expressed, assert perfectly clearly that these limitations—rashly assumed to be permanent—are revealed by means of heredity. They also plainly show that de Vries, in maintaining the uselessness of 'fluctuations' as the material for progressive evolution, is merely availing himself of a principle established much earlier and
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A331
Book:
Poulton, Edward Bagnall. 1909. Charles Darwin and the Origin of species: addresses, etc., in America and England in the year of the two anniversaries. London: Longmans, Green, and Co.
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will endeavour to express as clearly as possible, may do something to b1ing within reasonable limits those unduly exaggerated estimates of recent achievement which tend in the long run to diminish rather than to exalt the fame of an investigator. CHARLES DARWIN. It has been shown on many pages of this book that Darwin recognized large variations transitional into individual differences, but that, with A. R. Wallace, he believed the onward steps of evolution were supplied by the latter and not by
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first or the last word about organic evolution. His ideas as to the precise mode of evolution may be, and are [page] 2
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have been modified had Mendel's work come into his hands we can never know. He carefully considered the question of mutation, or as they called it then, saltation, and as time went on, he attached less and less importance to these variations as factors in the origin of species. Ray Lankester has recently reminded us that Darwin's disciple and expounder Huxley clung to a little heresy of his own as to the occurrence of evolution by saltatory variation and there must have been frequent and
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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medusoid from a free-swimming animal to a mere brood-sac (gonophore) is not sudden and saltatory, but occurs by imperceptible modifications throughout hundreds of years, as we can learn from the numerous stages of the process of degeneration persisting at the same time in different species. If, then, the degeneration to a simple brood-sac takes place only by very slow transitions, each stage of which may last for centuries, how could the much more complex ascending evolution possibly have
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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could be regarded as a serious rival to it. That selection is a factor, and a very powerful factor in the evolution of organisms, can no longer be doubted. Even although we cannot bring forward formal proofs of it in detail, cannot calculate definitely the size of the variations which present themselves, and their selection-value, cannot, in short, reduce the whole process to a mathematical formula, yet we must assume selection, because it is the only possible explanation applicable to whole
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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type, thus constituting obvious novelties. So it is in other cases described by Korschinsky: these sports or mutations are now recognised to be the main source of varieties of horticultural plants. As already stated, I do not pretend that the production of horticultural novelties is the prototype of the origin of new species in nature. I assume that they are, as a rule, derived from the parent species by the loss of some organ or quality, whereas the main lines of the evolution of the animal and
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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the 2nd edition of Evolution, Old and New, repeats his earlier expression of homage to one whom he had come to regard as an enemy: To the end of time, if the question be asked, 'Who taught people to believe in Evolution?' the answer must be that it was Mr. Darwin. This is true, and it is hard to see what palm of higher praise can be awarded to any philosopher. 2 Life and Letters, I. pp. 276 and 83. [page] 8
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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fashioned people of these totems, they circumcised them all, except the Plum Tree men, by means of a fire-stick. After that, having done the work of creation or evolution, the Ungambikula turned themselves into little lizards which bear a name meaning snappers-up of flies1. This Arunta tradition of the origin of man, as Messrs Spencer and Gillen, who have recorded it, justly observe, is of considerable interest; it is in the first place evidently a crude attempt to describe the origin of human
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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evolution. If we wish to form a mental image of the process of evolution we have to reckon with the possibility that parthenogenetic propagation may have preceded sexual reproduction. This suggests also the possibility that at that period outside forces may have supplied the conditions for the development of the egg which at present the spermatozoon has to supply. For this, if for no other reason, a brief consideration of the means of artificial parthenogenesis may be of interest to the student of
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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we may follow Darwin in calling appreciation, if we empty this word of the aesthetic implications which have gathered round it in the mental life of man. Regarded from this standpoint sexual selection, broadly considered, has probably been of great importance. The psychological accompaniments of the pairing situation have profoundly influenced the course of biological evolution and are themselves the outcome of that evolution. Darwin makes only passing reference to those modes of behaviour in
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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selection beneficial variations of all kinds will have been preserved and injurious ones eliminated. Darwin was too good an observer and too honest a man to minimise the enormous difference between the level of mental attainment of civilised man and that reached by any animal. His contention was that the difference, great as it is, is one of degree and not of kind. He realised that, in the development of the mental faculties of man, new factors in evolution have supervened—factors which play but
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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of education to bring educable human beings into vital contact, than has Charles Darwin. His special field of work was the wide province of biology; but he did much to help us realise that mental factors have contributed to organic evolution and that in man, the highest product of Evolution, they have reached a position of unquestioned supremacy. [page 446
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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. Now, in Spencer, evolution gave us a vitalist mechanic or mechanical vitalism, and the appeal seemed cut off. We may return to this point later when we consider evolution; at present I only endeavour to indicate that general pressure of scientific criticism which drove men of faith to seek the grounds of reassurance in a science of their own; in a method of experiment, of observation, of hypothesis checked by known facts. It is impossible for me to do more than glance across the threshold of
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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or refuting of an orthodoxy but on the genesis and evolution of a capacity, not on perfection but on process. Continuous evolution leaves no gap for revelation sudden and complete. We have henceforth to ask, not 1 1871. 2 6th edition, p. 428. 3 Life and Letters, Vol. III. p. 151. D. 32 [page] 49
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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His Prolegomena to Homer (1795) announced new modes of attack. Historical investigation was soon transformed by the elaboration of new methods. 5. Progress involves a judgment of value, which is not involved in the conception of history as a genetic process. It is also an idea distinct from that of evolution. Nevertheless it is closely related to the ideas which revolutionised history at the beginning of the last century; it swam into men's ken simultaneously; and it helped effectively to
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A162
Book:
Seward, A. C. ed. 1909. Darwin and modern science. Essays in commemoration of the centenary of the birth of Charles Darwin and of the fiftieth anniversary of the publication of The origin of species. Cambridge: Cambridge University Press.
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Further than this, I would ask whether the same train of ideas does not also apply to the evolution of animals? A species is well adapted to its environment when the individual can withstand the shocks of famine or the attacks and competition of other animals; it then possesses a high degree of stability. Most of the casual variations of individuals are indifferent, for they do not tell much either for or against success in life; they are small oscillations which leave the type unchanged. As
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