 | 1886 - Страниц: 400
...the theory of Natural Selection, we can clearly see why she should not ; for Natural Selection acts only by taking advantage of slight successive variations ; she can never take a great, sudden leap, but must advance by short and sure, though slow, steps." If we ask Mr. Danvin once more... | |
 | 1871 - Страниц: 608
...third edition of his ' Origin of Species ' the following passages : — ' Natural selection can act only by taking advantage of slight successive variations ; she can never take a leap, but must advance by short and slow steps ' (p. 214). Again he says : — ' If it could be demonstrated... | |
 | 1871 - Страниц: 860
...doubtless form a landmark in the domain of zoological science sages : — " Natural selection can act only by taking advantage of slight successive variations ; she can never take a leap, but must advance by short and slow steps" (p. 214). Again he says: — "If it could be demonstrated... | |
 | Charles Darwin - 1861 - Страниц: 470
...of natural selection, we can clearly understand why she should not ; for natural selection can act only by taking advantage of slight successive variations ; she can never take a leap, but must advance by the shortest and slowest steps. Organs of little apparent importance. —... | |
 | Charles Darwin - 1864 - Страниц: 472
...of natural selection, we can clearly understand why she should not ; for natural selection can act only by taking advantage of slight successive variations ; she can never take a leap, but must advance by the shortest and slowest steps. ' Organs of little apparent importance. —... | |
 | 1871 - Страниц: 650
...third edition of his ' Origin of Species ' the following passages : — ' Natural selection can act only by taking advantage of slight successive variations; she can never take a leap, but must advance by short and slow steps' (p. 214). Again he says : — ' If it could be demonstrated... | |
 | 1871 - Страниц: 446
...third edition of his ' Origin of Species ' the following passages : — ' Natural selection can act only by taking advantage of slight successive variations ; she can never take a leap, but must advance by short and slow steps.' — (p. 214.) Again, he says — ' If it could be... | |
 | 1871 - Страниц: 606
...third edition of his ' Origin of Species ' the following passages : — ' Natural selection can act only by taking advantage of slight successive variations ; she can never take a leap, but must advance by short and slow steps ' (p. 214). Again he says : — ' If it could be demonstrated... | |
 | American Philosophical Society - 1873 - Страниц: 662
...the elaborate classification in which we now behold it. Thus, Darwin says, "Natural selection acts only by taking advantage of slight successive variations ; she can never take a sudden leap, but must advance by short and sure, though slow, steps." Ib. 190. " New variations are... | |
 | American Philosophical Society - 1873 - Страниц: 626
...the elaborate classification in which we now behold it. Thus, Darwin says, "Natural selection acts only by taking advantage of slight successive variations ; she can never take a sudden leap, but must advance by short and sure, though slow, steps." Ib. 190. "New variations are... | |
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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... 
