Search Results - The Complete Work of Charles Darwin Online

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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. Text Image PDF

therefore of interest to compare, in a brief introductory section, the older with the newer teleological views. The distinctive feature of Natural Selection as contrasted with other attempts to explain the process of Evolution is the part played by the struggle for existence. All naturalists in all ages must have known something of the operations of Nature red in tooth and claw ; but it was left for this great theory to suggest that vast extermination is a necessary condition of progress, and even

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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. Text Image PDF

older naturalists who thought and spoke with Burchell of the intention of Nature and the adaptation of beings to each other, and to the situations in which they are found, could have conceived the possibility of evolution, they must have been led, as Darwin was, by the same considerations to Natural Selection. This was impossible for them, because the philosophy which they followed contemplated the phenomena of adaptation as part of a static immutable system. Darwin, convinced that the system

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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. Text Image PDF

movements. This suggests that the perfect imitation in shape, as well as in movement, seen in many species was started in forms of an appropriate size and colour by the mimicry of movement alone. Up to the present time Burchell is the only naturalist who has observed an example which still exhibits this ancestral stage in the evolution of mimetic likeness. Following the teachings of his day, Burchell was driven to believe that it was part of the fixed and inexorable scheme of things that these

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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. Text Image PDF

Bates in Life and Letters, II. p. 392. 4 See Poulton, Essays on Evolution, 1908, pp. 65, 85-88. 5 New Ser. Vol. III. 1863, p. 219. 6 Ed. 1872, pp. 375-378. 7 Ed. 1874, pp. 323-325. 8 More Letters, I. p. 176. [page] 28

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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. Text Image PDF

example. In Hypolimnas itself the females mimic Danainae with patterns very different from those preserved by the non-mimetic males: in the sub-genus Euralia, both sexes resemble the black and white Ethiopian Danaines with patterns not very dissimilar from that which we infer to have existed in the non-mimetic ancestor. (7) Although a melanic form or other large variation may be of the utmost importance in facilitating the start of a mimetic likeness, it is impossible to explain the evolution

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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. Text Image PDF

modification in the course of their descent2. We need not be surprised then, that in writing in 1845 to Sir Joseph Hooker, he speaks of that grand subject, that almost keystone of the laws of creation, Geographical Distribution3. Yet De Candolle was, as Bentham saw, unconsciously feeling his way, like Lyell, towards evolution, without being able to grasp it. They both strove to explain phenomena by means of agencies which they saw actually at work. If De Candolle gave up the ultimate problem as

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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. Text Image PDF

from a supposed primitive viscosity or plasticity of the earth's mass. For during this course of evolution the earth's mass must have suffered a screwing motion, so that the polar regions have travelled a little from west to east relatively to the equator. This affords a possible explanation of the north and south trend of our great continents4. It would be trespassing on the province of the geologist to pursue the subject at any length. But as Wallace5, who has admirably vindicated 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. Text Image PDF

cannot be doubted that this and the great memoir on the Distribution of Arctic Plants were only less epoch-making than the Origin itself, and must have supplied a powerful support to the general theory of organic evolution. Darwin always asserted his entire ignorance of Botany5. But this was only part of his constant half-humorous self-depreciation. He had been a pupil of Henslow, and it is evident that he had a good working knowledge of systematic botany. He could find his way about in the

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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. Text Image PDF

immutability of the species, which implies an enormous age, logically since the dawn of creation, to him the actually existing species as the latest results of evolution, were necessarily something very new, so young that only the very latest of the geological epochs could have affected them. It has since come to our knowledge that a great number of terrestrial recent species, even those of the higher classes of Vertebrates, date much farther back than had been thought possible. Many of them reach well

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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. Text Image PDF

mass of facts. A map (a hypothetical sketch ) shows the monophyletic origin and the routes of distribution of Man. Natural Selection may be all-mighty, all-sufficient, but it requires time, so much that the countless aeons required for the evolution of the present fauna were soon felt to be one of the most serious drawbacks of the theory. Therefore every help to ease and shorten this process should have been welcomed. In 1868 M. Wagner2 came to 1 Murray, The Geographical Distribution of Mammals, p

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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. Text Image PDF

selectionists Wagner's theory came to grow into an alternative instead of a help to the theory of selectional evolution. Separation is now rightly considered a most important factor by modern students of geographical distribution. For the same year, 1868, we have to mention Huxley, whose Arctogaea and Notogaea are nothing less than the reconstructed main masses of land of the Mesozoic period. Beyond doubt the configuration of land at that remote period has left recognisable traces in the present

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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. Text Image PDF

then, if the idea of generally applicable regions is a mare's nest, as was the search for the Holy Grail, what is the object of the study of geographical distribution? It is nothing less than the history of the evolution of life in space and time in the widest sense. The attempt to account for the present distribution of any group of organisms involves the aid of every branch of science. It bids fair to become a history of the world. It started in a mild, statistical way, restricting itself 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. Text Image PDF

It is the first of these inquiries which specially interests the geologist; though geology undoubtedly played a part—and by no means an insignificant part—in respect to the second inquiry. When, indeed, the history comes to be written of that great revolution of thought in the nineteenth century, by which the doctrine of evolution, from being the dream of poets and visionaries, gradually grew to be the accepted creed of naturalists, the paramount influence exerted by the infant science 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. Text Image PDF

later2. It is a question of great interest to determine the period and the occasion of Darwin's first awakening to the great problem of the transmutation of species. He tells us himself that his grandfather's Zoonomia had been read by him but without producing any effect, and that his friend Grant's rhapsodies on Lamarck and his views on evolution only gave rise to astonishment3. Huxley, who had probably never seen the privately printed volume of letters to Henslow, expressed the opinion that Darwin

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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. Text Image PDF

geological work that led Darwin into those paths of research which in the end conducted him to his great discoveries. I quite agree with the view expressed by Mr F. Darwin and Professor Seward, that Darwin, like Lyell, thought it 'almost useless' to try to prove the truth of evolution until the cause of change was discovered1, and that possibly he may at times have vacillated in his opinions, but I believe there is evidence that, from the date mentioned, the species question was always more or less

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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. Text Image PDF

of South American fossils, and species on Galapagos Archipelago. These facts (especially latter), origin of all my views1, it is clear that he must refer, not to his first inception of the idea of evolution, but to the flood of recollections, the reawakening of his interest in the subject, which could not fail to result from the sight of his specimens and the reference to his notes. Except during the summer vacation, when he was visiting his father and uncle, and with the latter making his first

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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. Text Image PDF

, will at once reject the theory —as indeed they must reject any theory of evolution. The striking passage with which Darwin concludes this chapter—in which he compares the record of the rocks to the much mutilated volumes of a human history—remains as apt an illustration as it did when first written. And the second geological chapter, on the Succession of Organic Beings—though it has been strengthened in a thousand ways, by the discoveries concerning the pedigrees of the horse, the elephant 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. Text Image PDF

an earlier essay, Huxley had spoken of the doctrine of Uniformitarianism as being, in a certain sense, opposed to that of Evolution2; but in his later years he took up a very different and more logical position, and maintained that Consistent uniformitarianism postulates evolution as much in the organic as in the inorganic world. The origin of a new species by other than ordinary agencies would be a vastly greater 'catastrophe' than any of those which Lyell success fully eliminated from sober

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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. Text Image PDF

surrendered himself to his enthusiasm for an idea. To his firm faith in the doctrine of continuity we owe the Origin of Species; and while Darwin became the Paul of evolution, Lyell long remained the doubting Thomas. Many must have felt like H. C. Watson when he wrote: How 1 Lyell's Life, Letters and Journals, Vol. II. p. 44. 2 L. L. I. p. 296. [page] 38

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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. Text Image PDF

. It is quite possible to conceive this occurring in plants which have no power of circumnutating—and, as already pointed out, physiologists do as a fact neglect circumnutation as a factor in the evolution of movements. Whatever may be the fate of Darwin's theory of circumnutation there is no doubt that the research he carried out in support of, and by the light of, this hypothesis has had a powerful influence in guiding the modern theories of the behaviour of plants. Pfeffer1, who more than any