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acquired characters adaptive characters adduced admit animals appears argument argument from ignorance artificial selection become cause cessation of selection chapter climatic co-adaptation colour concerned congenital connexion continuity correlation Darwin Darwinian deduction definition degeneration degree disuse doctrine due to natural epilepsy evidence experiments explain fact favour force of heredity Galton genera germ-plasm hereditary importance individuals inherited effects instincts kind Lamarck Lamarckian factors Lamarckian principles large proportional number less Lloyd Morgan matter merely modifications natural selection naturalists necessarily niata observed occur opinion organic evolution origin of species pangenesis panmixia particular peculiar plants possible present produced Professor Weismann's progeny prove question reason reflex action reflex mechanism regard remark restiform body reversal of selection sciatic nerve sexual selection somatogenetic specific characters statement structure sufficient suppose theory of heredity theory of natural tion transmission of acquired transmitted use-inheritance useless characters utility variations varieties Wallace Wallace's Weismann
Page 316 - I did not formerly consider sufficiently the existence of structures, which, as far as we can at present judge, are neither beneficial nor injurious; and this I believe to be one of the greatest oversights as yet detected in my work.
Page 5 - But as my conclusions have lately been much misrepresented, and it has been stated that I attribute the modification of species exclusively to natural selection, I may be permitted to remark that in the first edition of this work, and subsequently, I placed in a most conspicuous position — namely, at the close of the Introduction — the following words : " I am convinced that natural selection has been the main but not the exclusive means of modification.
Page 5 - This has been effected chiefly through the natural selection of numerous successive, slight, favourable variations; aided in an important manner by the inherited effects of the use and disuse of parts; and in an unimportant manner, that is in relation to adaptive structures, whether past or present, by the direct action of external conditions, and by variations which seem to us in our ignorance to arise spontaneously.
Page 4 - I have now recapitulated the facts and considerations which have thoroughly convinced me that species have been modified during a long course of descent. This has been effected chiefly through the natural selection of numerous successive, slight, favourable variations; aided in an important manner by the inherited effects of the use and disuse of parts; and in an unimportant manner, that is in relation to adaptive structures, whether past or present, by the direct action of external conditions, and...
Page 27 - ... conditions. On the hypothesis of this spiritual nature, superadded to the animal nature of man, we are able to understand much that is otherwise mysterious or unintelligible in regard to him, especially the enormous influence of ideas, principles, and beliefs over his whole life and actions.
Page 321 - The sutures in the skulls of young mammals have been advanced as a beautiful adaptation for aiding parturition, and no doubt they facilitate, or may be indispensable for this act; but as sutures occur in the .skulls of young birds and reptiles, which have only to escape from a broken egg, we may infer that this structure has arisen from the laws of growth, and has been taken advantage of in . the parturition of the higher animals.
Page 27 - Thus alone we can understand the constancy of the martyr, the unselfishness of the philanthropist, the devotion of the patriot, the enthusiasm of the artist, and the resolute and persevering search of the scientific worker after nature's secrets.
Page 4 - ... in comparison with those of the wild duck. A horse is trained to certain paces, and the colt inherits similar consensual movements. The domesticated rabbit becomes tame from close confinement; the dog, intelligent from associating with man ; the retriever is taught to fetch and carry ; and these mental endowments and bodily powers are all inherited.
Page 24 - ... can we conceive that early man, as an animal, gained anything by purely erect locomotion ? Again, the hand of man contains latent capacities and powers which are unused by savages, and must have been even less used by palaeolithic man and his still ruder predecessors. It has all the appearance of an organ prepared for the use of civilized man, and one which was required to render civilization possible.
Page 195 - ... but during the great droughts, when so many animals perish, the niata breed is under a great disadvantage, and would be exterminated if not attended to; for the common cattle, like horses, are able just to keep alive, by browsing with their lips on twigs of trees and reeds ; this the niatas cannot so well do, as their lips do not join, and hence they are found to perish before the common cattle. This strikes me as a. good illustration of how little we are able to judge from the ordinary habits...