 | 1886 - 400 páginas
...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 to consider what the facts of Nature teach in this respect, he replies... | |
 | Charles Darwin - 1866 - 668 páginas
...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...natural selection acts by life and death, — by the preservation of individuals with any favourable variation, and by the destruction of those with any... | |
 | 1909 - 846 páginas
...for natural selection selects only by taking advantage of slight successive variations; sue can never take a great and sudden leap, but must advance by short and sure, though slow steps. In attempting to explain the puzzling phenomenon of the so-called neuter, really undeveloped female... | |
 | Charles Darwin - 1873 - 492 páginas
...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...slow steps. Organs of little apparent Importance, as a/ected by Natural Selection. As natural selection acts by life and death,—by the survival of the... | |
 | American Philosophical Society - 1873 - 626 páginas
..."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 very slowly formed, for variation is a slow process, and natural selection... | |
 | American Philosophical Society - 1873 - 662 páginas
..."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 very slowly formed, for variation is a slow process, and natural selection... | |
 | Charles Darwin - 1875 - 504 páginas
...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...Organs of little apparent Importance, as affected by Katural Selection. As natural selection acts by life and death, — by the survival of the fittest,... | |
 | American Philosophical Society - 1878 - 642 páginas
...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 very slowly formed, for variation is a slow process, and natural selection... | |
 | Alexander Wilford Hall - 1877 - 546 páginas
...— "Natural selection acts only by taking advantage of slight successive variations. She can neiir take a great and sudden leap, but must advance by short and sure though slow steps." — Origin tj Species, p. 156. Then, it follows, as there are no two species in the world, and never... | |
 | Alexander Wilford Hall - 1880 - 544 páginas
..."Natural selection acts only by taking advantage of slight successive variations. She can never tahe a great and sudden leap, but must advance by short and sure though slow steps." — Origin of Species, p. 156. Then, it follows, as there are no two species in the world, and never... | |
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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... 
