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able action adapted admit ages allied American animals appeared Asa Gray beauty become beetles believe birds bone causes characters closely colour common complete conclusion created creation descended developed discovered distinct doubt early earth effects evidence evolution exactly existence extinct facts flowers follows forms genus give given groups habits Hence horse important improved individuals inhabitants inherited insects instincts kind known latter laws leading leaves less living look males manner marked means mind modification namely natural selection naturalists never once organic origin past period plants possess present principle probably produced progenitor protective relation remains resemble rest result scale seems seen sexes similar slight special creations species structure successive teeth tend theory tints tion trees understand variation varieties various whole widely wild wings wonderful
Página 37 - I happened to read for amusement 'Malthus on Population,' and being well prepared to appreciate the struggle for existence which everywhere goes on from long-continued observation of the habits of animals and plants, it at once struck me that under these circumstances favourable variations would tend to be preserved, and unfavourable ones to be destroyed. The result of this would be the formation of new species. Here then I had at last got a theory by which to work...
Página 34 - There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.
Página 68 - Important as the struggle for existence ha^s been and even still is, yet as far as the highest part of man's nature is concerned there are other agencies more important. For the moral qualities are advanced, either directly or indirectly, much more through the effects of habit, the reasoning powers, instruction, religion, etc., than through natural selection ; though to this latter agency the social instincts, which afforded the basis for the development of the moral sense, may be safely attributed.
Página 33 - These laws, taken in the largest sense, being Growth with Reproduction; Inheritance which is almost implied by reproduction, Variability from the indirect and direct action of the external conditions of life, and from use and disuse...
Página 29 - ... the summing up of the labour, the experience, the reason, and even the blunders of numerous workmen; when we thus view each organic being, how far more interesting — I speak from experience — does the study of natural history become!
Página 46 - ... man is descended from some less highly organized form. The grounds upon which this conclusion rests will never be shaken, for the close similarity between man and the lower animals in embryonic development, as well as in innumerable points of structure and constitution, both of high and of the most trifling importance — the rudiments which he retains, and the abnormal reversions to which he is occasionally liable — are facts which cannot be disputed.
Página 29 - We possess no pedigree or armorial bearings; and we have to discover and trace the many diverging lines of descent in our natural genealogies, by characters of any kind which have long been inherited. Rudimentary organs will speak infallibly with respect to the nature of long-lost structures. Species and groups of species which are called aberrant, and which may fancifully be called living fossils, will aid us in forming a picture of the ancient forms of life. Embryology will often reveal to us the...
Página 41 - I had, also, during many years followed a golden rule, namely, that whenever a published fact, a new observation or thought came across me, which was opposed to my general results, to make a memorandum of it without fail and at once; for I had found by experience that such facts and thoughts were far more apt to escape from the memory than favorable ones. Owing to this habit, very few objections were raised against my views which I had not at least noticed and attempted to answer.
Página 32 - In the distant future I see open fields for far more important researches. Psychology will be based on a new foundation, that of the necessary acquirement of each mental power and capacity by gradation. Light will be thrown on the origin of man and his history.