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A36
Periodical contribution:
Darwin Centenary Number. Christ's College Magazine. vol. XXIII, Easter Term, 1909.
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, many of the facts chronicled by Darwin many be said, in a certain sense, to have been the starting points of subsequent investigations, e.g. on such questions as wool production and fertility, the solutions of which are of the utmost importance to the stock raiser and practical agriculturist. In the second volume of the Animals and Plants, Darwin discusses the phenomena of inheritance, the effects of crossing and of inbreeding, and the nature of hybridism. The conception of evolution by
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A36
Periodical contribution:
Darwin Centenary Number. Christ's College Magazine. vol. XXIII, Easter Term, 1909.
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notice. But even now it cannot be contended that the Mendelian investigations, vastly important though these be to the student of heredity and the experimental breeder, have contributed much, at any rate as yet, towards the elucidation of the central problem which Darwin set out to solve, namely, the origin of species. It has recently been observed that although the evolution theory exerted so great an influence upon anatomy and kindred branches of biology, the science of physiology has always
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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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shortcomings in the correction of proofs. The two portraits of Darwin are reproduced by permission of Messrs Maull and Fox and Messrs Elliott and Fry. The photogravure of the study at Down is reproduced from an etching by Mr Axel Haig, lent by Mr Francis Darwin; the coloured plate illustrating Prof. Weismann's essay was originally published by him in his Vortr ge ber Descendenztheorie which afterwards appeared (1904) in English under the title The Evolution Theory. Copies of this plate were
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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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, Darwin just 1 See in particular Samuel Butler, Evolution Old and New, London, 1879; J. L. de Lanessan, Buffon et Darwin , Revue Scientifique, XLIII. pp. 385-391, 425-432, 1889. 2 op. cit. p. 136. 3 See Ernst Krause and Charles Darwin, Erasmus Darwin, London, 1879. [page] 1
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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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III THE SELECTION THEORY BY AUGUST WEISMANN. Professor of Zoology in the University of Freiburg (Baden). I. THE IDEA OF SELECTION. MANY and diverse were the discoveries made by Charles Darwin in the course of a long and strenuous life, but none of them has had so far-reaching an influence on the science and thought of his time as the theory of selection. I do not believe that the theory of evolution would have made its way so easily and so quickly after Darwin took up the cudgels in favour 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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theories, in the endeavour to penetrate more deeply into the problem of the evolution of the organic world. Within the narrow limits to which this paper is restricted, I cannot attempt to discuss any of these. V. ARGUMENTS FOR THE REALITY OF THE PROCESSES OF SELECTION. (a) Sexual Selection. Sexual selection goes hand in hand with natural selection. From the very first I have regarded sexual selection as affording an extremely important and interesting corroboration of natural selection, 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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, a special diploid generation was not represented. This, however, appeared later as a product of the further evolution of the zygote, and the reduction division was correspondingly postponed. In animals, as in plants, the diploid generation attained the higher development and gradually assumed the dominant position. The haploid generation suffered a proportional reduction, until it finally ceased to have an independent existence and became restricted to the role of producing the sexual products
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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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disturbs the logical sequence of his ideas as to the conditions which have brought about the evolution of man from lower forms. The instances of reversion here discussed are microcephalism, which Darwin wrongly interpreted as atavistic, supernumerary mammae, supernumerary digits, bicornuate uterus, the development of abnormal muscles, and so on. Brief mention is also made of correlative variations observed in man. Darwin next discusses the question as to the manner in which man attained to the erect
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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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, they were now combined together into one organic whole by the theory of descent and by the hypothesis of recapitulation which was deduced from that theory. The view1 that a knowledge of embryonic and larval histories would lay bare the secrets of race-history and enable the course of evolution to be traced, and so lead to the discovery of the natural system of classification, gave a powerful stimulus to morphological study in general and to embryological investigation in particular. In Darwin's
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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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succession of the rocks which make up the accessible crust of the earth, and this use has continued, without essential change, to the present day. It is true that the theory of evolution has greatly modified our conceptions concerning the introduction of new species and the manner in which palaeontological data are to be interpreted in terms of stratigraphy, but, broadly speaking, the method remains fundamentally the same as that introduced by Smith. The biological direction of palaeontology was due 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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doubt homosporous Lycopods existed, but the great prevalence of the higher mode of reproduction in days which to us appear ancient, shows how long a course of evolution must have already been passed through before the oldest known members of the group came into being. The other characters of the Palaeozoic Lycopods tell the same tale; most of them attained the stature of trees, with a corresponding elaboration of anatomical structure, and even the herbaceous forms show no special simplicity
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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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are unknown, it is obviously in the interest of further scientific progress to connect cause and effect directly whenever our knowledge allows us to do so. VII. CONCLUDING REMARKS. The discovery of De Vries, that new species may arise by mutation and the wide if not universal applicability of Mendel's Law to phenomena of heredity, as shown especially by Bateson and his pupils, must, for the time being, if not permanently, serve as a basis for theories of evolution. These discoveries place before
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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, Proc. R. Geogr. Soc. 1879, p. 427. 3 More Letters, II. p. 146. 4 Observations of a Naturalist in the Pacific between 1896 and 1899, London, 1903, I. p. 380. 5 Island Life, p. 105. [page] 30
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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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hemisphere had played an important part in the evolution of the vegetable kingdom did not mislead him. Nothing probably would have given him greater satisfaction than the masterly summary in which Seward has brought together the evidence for the origin of the Glossopteris flora in Gondwana land. A vast continental area, of which remnants are preserved in Australia, South Africa and South America...A tract of enormous extent occupying an area, part of which has since given place to a southern ocean
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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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certain actions, scarcely affords a satisfactory basis for genetic treatment. To carry out the spirit of Darwin's teaching it is necessary to link more closely biological and psychological evolution. The first step towards this is to interpret the phenomena of instinctive behaviour in terms of stimulation and response. It may be well to take a particular case. Swimming on the part of a duckling is, from the biological point of view, a typical example of instinctive behaviour. Gently lower a
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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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Bonald did, and Moltke after him, that war is a providential 1 tudes sur la S lection dans ses rapports avec l'h r dit chez l'homme, Paris, p. 481, 1881. 2 Die drei Bev lkerungsstufen, Munich, 1889. 3 Evolution and Ethics, p. 200; Collected Essays, vol. IX, London, 1894. [page] 47
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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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recoil of Christian apologetics towards the ground of religious experience, a recoil produced by the pressure of scientific criticism upon other supports of faith: The restatement, or the recovery of ancient forms of statement, of the doctrines of Creation and of divine Design in Nature, consequent upon the discussion of evolution and of natural selection as its guiding factor. (1) The first of these is quite possibly the most important of all. It was well defined in a notable paper read by Dr
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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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personal work of Darwin, and more definitely characteristic of the age in which his influence was paramount: viz. the influence of the two conceptions of evolution and natural selection upon the doctrine of creation and of design respectively. It is impossible here, though it is necessary for a complete sketch of the matter, to distinguish the different elements and channels of this Darwinian influence; in Darwin's own writings, in the vigorous polemic of Huxley, and strangely enough, but very
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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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savoured of impiety. In the brief space allotted me I can attempt only two things; first, and very briefly, I shall try to indicate the normal attitude towards religion in the early part of the last century; second, and in more detail, I shall try to make clear what is the outlook of advanced thinkers to-day1. From this second inquiry it will, I hope, be abundantly manifest that it is the doctrine of evolution that has made this outlook possible and even necessary. The ultimate and unchallenged
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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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XXVII DARWINISM AND HISTORY BY J. B. BURY, LITT.D., LL.D. Regius Professor of Modern History in the University of Cambridge. 1. Evolution, and the principles associated with the Darwinian theory, could not fail to exert a considerable influence on the studies connected with the history of civilised man. The speculations which are known as philosophy of history, as well as the sciences of anthropology, ethnography, and sociology (sciences which though they stand on their own feet are for the
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