Charles Darwin's Works: The origin of species by means of natural selection...with additions and corrections from 6th and last English edD. Appleton, 1896 |
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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 16 VARIATION UNDER DOMESTICATION . [ CHAP . I. reappear 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 16 VARIATION UNDER DOMESTICATION . [ CHAP . I. reappear 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 ...
Часто встречающиеся слова и выражения
acquired adapted advantage allied analogous appear Asa Gray beak become bees believe birds breeds caudicle cause cells characters climate closely colour common correlated crossed cuckoo degree developed difficulty distinct species disuse domestic animals domestic races doubt effects eggs existence extinct extremely facts favourable females flowers forms Fritz Müller genera genus giraffe gradations greater number groups habits Hence hermaphrodites hive-bee important improved increase in number individual differences inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ large number larger genera larvæ less likewise males manner Melipona Mivart natural selection naturalists nearly nest 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 relation remarked resemble rock-pigeon seeds sexes sexual sexual selection slight stamens sterile structure struggle supposed swimbladder tend tendency tion transitional tree variability variations varieties vary widely wings young
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Стр. 77 - We behold the face of nature bright with gladness, we often see superabundance of food ; we do not see or we forget, that the birds which are idly singing round us mostly live on insects or seeds, and are thus constantly destroying life ; or we forget how largely these songsters, or their eggs, or their nestlings, are destroyed by birds and beasts of prey...
Стр. 109 - ... perform strange antics before the females, which, standing by as spectators, at last choose the most attractive partner. Those who have closely attended to birds in confinement well know that they often take individual preferences and dislikes; thus Sir R. Heron has described how a pied peacock was eminently attractive to all his hen birds.
Стр. 229 - 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. 1 - These facts seemed to me to throw some light on the origin of species — that mystery of mysteries, as it has been called by one of our greatest philosophers.
Стр. 162 - ... 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. Of the many twigs which flourished when the tree was a mere bush, only two or three, now grown into great branches, yet survive and bear the other branches ; so with the species which lived during long-past geological periods, very few have left living and modified descendants.
Стр. 203 - Our ignorance of the laws of variation is profound. Not in one case out of a hundred can we pretend to assign any reason why this or that part differs, more or less, from the same part in the parents.
Стр. 77 - I have called this principle, by which each slight variation, if useful, is preserved, by the term natural selection, in order to mark its relation to man's power of selection. But the expression often used by Mr. Herbert Spencer, of the Survival of the Fittest, is more accurate, and is sometimes equally convenient.
Стр. 163 - From the first growth of the tree, many a limb and branch has decayed and dropped off; and these lost branches of various sizes may represent those whole orders, families, and genera which have now no living representatives, and which are known to us only from having been found in a fossil state.
Стр. 244 - Why should not Nature take a sudden leap from structure to structure? On the theory of natural selection, we can clearly understand why she should not; for natural selection acts only by taking advantage of slight successive variations; she can never take a great and sudden leap, but must advance by short and sure, though slow steps.
Стр. 138 - The truth of the principle, that the greatest amount of life can be supported by great diversification of structure^ is seen under many natural circumstances. In an extremely small area, especially if freely open to immigration, and where the contest between individual and individual must be severe, we always find great diversity in its inhabitants. For instance, I found that a piece of turf, three feet by four in size, which had been...