We cannot suppose that all the c — ac x1 breeds were suddenly produced as perfect and as useful as we now see them ; indeed, in many cases, we know that this has not been their history. The key is man's power of accumulative selection : nature gives... The Origin of Species - Página 46por Charles Darwin - 1909 - 552 páginasVista completa - Acerca de este libro
| 1861 - 716 páginas
...these causes of change, however, man's power of accumulative selection predominates. (Pp. 44, 45.) "Nature gives successive variations; man adds them...directions useful to him. In this sense, he may be said to make for himself useful breeds." (P. 34-.) In this manner new races or varieties are produced within... | |
| 1860 - 512 páginas
...mazes in which he henceforth continues to wander. He attributes the varieties of domestic animals to "Man's power of accumulative selection ; nature gives...adds them up in certain directions useful to him." We object to this, as altogether a partial and imperfect statement. It is not nature that gives the... | |
| Robert Kemp Philp - 1860 - 360 páginas
...in his eyes, we must, I think, look further than to mere variability. We cannot suppose that all the breeds were suddenly produced as perfect and as useful as we now see them ; indeed, in several cases, we know that this has not been their history. The key is man's power of accumulative... | |
| 1860 - 656 páginas
...contrary impression in the mind of the trusting reader. " We cannot suppose," he says, "that all the breeds were suddenly produced as perfect and as useful as we now see them; indeed, in several cases, we know that this has not been their history. The key is man's power of accumulative... | |
| Charles Darwin - 1861 - 470 páginas
...in his eyes, we must, I think, look further than to mere variability. We cannot suppose that all the breeds were suddenly produced as perfect and as useful as we now see them ; indeed, in several cases, we know that this has not been their history. The key is man's power of accumulative... | |
| 1910 - 828 páginas
...that the improved breeds had been obtained in this manner. He says : We can not suppose that all the breeds were suddenly produced as perfect and as useful...sense he may be said to have made for himself useful breeds.1 1 Contribution VI, Laboratory Experimental Plant-breeding, Cornell University. The writer... | |
| 1872 - 520 páginas
..."We are profoundly ignorant of the cause of each slight variation or individual difference (p. 192). "Nature gives successive variations; man adds them up in certain directions useful to him " (p. 40). We italicise man because ^we are convinced that the grand fallacy in Darwin's theory lies... | |
| American Philosophical Society - 1873 - 662 páginas
...conditions. Of the variation produced by selection in breeding and the better care of animals, Darwin says, "the key is man's power of accumulative selection...may be said to have made for himself useful breeds." Origin of Species, 40. But what does nature do when man docs not seize upon the offered variations... | |
| Charles Darwin - 1875 - 504 páginas
...in his eyes, we must, I think, look further than to mere variability. We cannot suppose that all the Breeds were suddenly produced as perfect and as useful...cases, we know that this has not been their history. Tho key is man's power of accumulative selection : nature gives successive variations ; man adds them... | |
| American Philosophical Society - 1878 - 616 páginas
...conditions. Of the variation produced by selection in breeding and the better care of animals, Darwin says, "the key is man's power of accumulative selection...may be said to have made for himself useful breeds. ' ' Origin of Species, 40. But what does nature do when man does not seize upon the offered variations... | |
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