The Origin of Species by Means of Natural Selection: Or, The Preservation of Favored Races in the Struggle for Life, Том 1D. Appleton & Company, 1889 |
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Стр. xv
... tend to progress , in order to account for the existence at the present day of simple productions , he maintains that such forms are now spontaneously generated . Geoffroy Saint - Hilaire , as is stated in his Life , ' written by his ...
... tend to progress , in order to account for the existence at the present day of simple productions , he maintains that such forms are now spontaneously generated . Geoffroy Saint - Hilaire , as is stated in his Life , ' written by his ...
Стр. xvi
... tend to vary in some degree , and , secondly , that agri- culturists improve their domesticated animals by selec- tion ; and then , he adds , but what is done in this latter case " by art , seems to be done with equal efficacy , though ...
... tend to vary in some degree , and , secondly , that agri- culturists improve their domesticated animals by selec- tion ; and then , he adds , but what is done in this latter case " by art , seems to be done with equal efficacy , though ...
Стр. 5
... tend to propagate its new and modified form . This fundamental subject of Natural Selection will be treated at some length in the fourth chapter ; and we shall then see how Natural Selection almost in- evitably causes much Extinction of ...
... tend to propagate its new and modified form . This fundamental subject of Natural Selection will be treated at some length in the fourth chapter ; and we shall then see how Natural Selection almost in- evitably causes much Extinction of ...
Стр. 15
... more important rule , which I think may be trusted , is that , at whatever period of life a peculiarity first appears , it tends to reappear in the offspring at a corresponding age , though CHAP . I. ] VARIATION UNDER DOMESTICATION . 15.
... more important rule , which I think may be trusted , is that , at whatever period of life a peculiarity first appears , it tends to reappear in the offspring at a corresponding age , though CHAP . I. ] VARIATION UNDER DOMESTICATION . 15.
Стр. 16
... tend to appear in the offspring at the same period at which it first appeared in the parent . I believe this rule to be of the highest importance in explaining the laws of embryology . These remarks are of course confined to the first ...
... tend to appear in the offspring at the same period at which it first appeared in the parent . I believe this rule to be of the highest importance in explaining the laws of embryology . These remarks are of course confined to the first ...
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Часто встречающиеся слова и выражения
adapted advantage allied analogous animals and plants appear Asa Gray beak become bees believe birds breeds caudicle cause cells characters climate closely Cloth colour common crossed cuckoo degree descendants developed difficulty distinct species disuse domestic animals domestic races doubt effects eggs existence extinct extremely facts favourable females flowers forms Fritz Müller genera genus gradations greater number groups habits Hence hermaphrodites hive-bee important improved inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ large number larger genera larvæ less likewise males manner Mivart modified natural selection naturalists nearly nest neuters occasionally offspring organisation organs origin ORIGIN OF SPECIES parent perfect period pigeons pollen pollen-grains present preserved principle probably produced progenitor quadrupeds rank Red Grouse remarked resemble rock-pigeon seeds sexes sexual sexual selection slight stamens structure struggle sub-breeds supposed swimbladder tend tendency tion transitional tree tumbler pigeon variability variations varieties vary widely wild wings young
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Стр. 227 - If it could be proved that any part of the structure of any one species had been formed for the exclusive good of another species, it would annihilate my theory, for such could not have been produced through natural selection.
Стр. 203 - 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. 75 - Several writers have misapprehended or objected to the term Natural Selection, Some have even imagined that natural selection induces variability, whereas it' implies only the. preservation of such variations as arise and are beneficial to the being under its conditions of * life.
Стр. xxv - As many more individuals of each species are born than can possibly survive ; and as, consequently, there is a frequently recurring straggle for existence, it follows that any being, if it vary however slightly in any manner profitable to itself, under the complex and sometimes varying conditions of life, will have a better chance of surviving, and thus be naturally selected.
Стр. xix - 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. 144 - It is well known that several animals, belonging to the most different classes, which inhabit the caves of Carniola and of Kentucky, are blind. In some of the crabs the foot-stalk for the eye remains, though the eye is gone; — the stand for the telescope is there, though the telescope with its glasses has been lost. As it is difficult to imagine that eyes, though useless, could be in any way injurious to animals living in darkness, their loss may be attributed to disuse.
Стр. 55 - Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult — at least I have found it so — than constantly to bear this conclusion in mind.
Стр. 341 - Cloth, $2.00. DIFFERENT FORMS OF FLOWERS ON PLANTS OF THE SAME SPECIES. With Illustrations. 12mo. Cloth, $1.50. THE POWER OF MOVEMENT IN PLANTS. By CHARLES DARWIN, LL. D., FRS, assisted by FRANCIS DARWIN.
Стр. 140 - The limbs divided into great branches, and these into lesser and lesser branches, were themselves once, when the tree was small, budding twigs; and this connection of the former and present buds by ramifying branches may well represent the classification of all extinct and living species in groups subordinate to groups.
Стр. 140 - The affinities of all the beings of the same class have sometimes been represented by a great tree. I believe this simile largely speaks the truth. The green and budding twigs may represent existing species ; and those produced during each former year may represent the long succession of extinct species.