On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favored Races in the Struggle of LifeAppleton, 1864 - Всего страниц: 440 |
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Стр. v
... perfect gradation of the forms in certain groups , and by the anal- ogy of domestic productions . With respect to the means of modification , he attributed something to the action of external conditions , something to the crossing of ...
... perfect gradation of the forms in certain groups , and by the anal- ogy of domestic productions . With respect to the means of modification , he attributed something to the action of external conditions , something to the crossing of ...
Стр. 6
... perfect - The law of Unity of Type and of the Conditions of Existence embraced by the theory of Natural Selection , 154 • • CHAPTER VII . INSTINCT . Instincts comparable with habits , but different in their origin - Instincts graduated ...
... perfect - The law of Unity of Type and of the Conditions of Existence embraced by the theory of Natural Selection , 154 • • CHAPTER VII . INSTINCT . Instincts comparable with habits , but different in their origin - Instincts graduated ...
Стр. 20
... perfect reversion had ensued . It would be quite necessary , in order to prevent the effects of intercrossing , that only a single variety should be turned loose in its new home . Nevertheless , as our varieties certainly do ...
... perfect reversion had ensued . It would be quite necessary , in order to prevent the effects of intercrossing , that only a single variety should be turned loose in its new home . Nevertheless , as our varieties certainly do ...
Стр. 21
... perfect fertility of varieties when crossed , -a subject hereafter to be dis cussed ) , domestic races of the same species differ from each other in the same manner as , only in most cases in a lesser degree than , do closely - allied ...
... perfect fertility of varieties when crossed , -a subject hereafter to be dis cussed ) , domestic races of the same species differ from each other in the same manner as , only in most cases in a lesser degree than , do closely - allied ...
Стр. 27
... perfect plu- mage is acquired varies , as does the state of the down with which the nestling birds are clothed when hatched . The shape and size of the eggs vary . The manner of flight differs remarkably ; as does in some breeds the ...
... perfect plu- mage is acquired varies , as does the state of the down with which the nestling birds are clothed when hatched . The shape and size of the eggs vary . The manner of flight differs remarkably ; as does in some breeds the ...
Другие издания - Просмотреть все
The Origin of Species by Means of Natural Selection: Or, The ..., Том 1 Charles Darwin Полный просмотр - 1889 |
The Origin of Species by Means of Natural Selection: Or, the ..., Том 1 Charles Darwin Полный просмотр - 1898 |
Часто встречающиеся слова и выражения
accumulated adapted affinities allied species America amount ancient animals appear become bees believe birds breeds cause cells characters cirripedes climate closely allied colour continuous crossed crustaceans degree difficulty distinct species disuse divergence domestic doubt embryo endemic Europe existing exterminated extinct extremely facts favourable fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hermaphrodites hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing intermediate land larvæ less living look male mammals manner migration modification modified descendants natural selection naturalists nearly nest offspring organic organisation perfect pigeons pistil plants pollen present probably produced progenitor ranked reciprocal crosses remarked resemble rudimentary seeds seems sexual selection Silurian slight South America sterility structure struggle successive suppose swimbladder tend theory tion trees variability variation varieties vary whole widely
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Стр. 424 - 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.
Стр. 63 - There is no exception to the rule that every organic being naturally increases at so high a rate, that, if not destroyed, the earth would soon be covered by the progeny of a single pair.
Стр. 79 - I may be allowed to personify the natural preservation or survival of the fittest, cares nothing for appearances, except in so far as they are useful to any being. She can act on every internal organ, on every shade of constitutional difference, on the whole machinery of life. Man selects only for his own good: Nature only for that of the being which she tends.
Стр. 70 - I counted thirtytwo little trees ; and one of them, with twenty-six rings of growth, had during many years tried to raise its head above the stems of the heath, and had failed. No wonder that, as soon as the land was enclosed, it became thickly clothed with vigorously growing young firs. Yet the heath was so extremely barren and so extensive that no one would ever have imagined that cattle would have so closely and effectually searched it for food. Here we see that cattle absolutely determine the...
Стр. 169 - If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.
Стр. 63 - Hence as more individuals are produced than can possibly survive, there must in every case be a struggle for existence, either one individual with another of the same species, or with the individuals of distinct species, or with the physical conditions of life.
Стр. 167 - To suppose that the eye with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest degree.
Стр. 378 - Nothing can be more hopeless than to attempt to explain this similarity of pattern in members of the same class, by utility or by the doctrine of final causes. The hopelessness of the attempt has been expressly admitted by Owen in his most interesting work on the 'Nature of Limbs.
Стр. 187 - Under changed conditions of life, it is at least possible that slight modifications of instinct might be profitable to a species; and if it can be shown that instincts do vary ever so little, then I can see no difficulty in natural selection preserving and continually accumulating variations of instinct to any extent that was profitable. It is thus, as I believe, that all the most complex and wonderful instincts have originated.
Стр. 165 - I can see no difficulty in a race of bears being rendered, by natural selection, more and more aquatic in their structure and habits, with larger and larger mouths, till a creature was produced as monstrous as a whale.