 | 1897 - Страниц: 490
...variations within the limitations of a common species. Since Charles Darwin enunciated the proposition that favourable variations would tend to be preserved, and unfavourable ones to be destroyed, and that the result of this double action, by the accumulation of minute existing differences, would... | |
 | 1845 - Страниц: 960
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 | 1949 - Страниц: 784
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 | Charles Frederick Holder - 1891 - Страниц: 374
...obtained the idea that in the struggle for existence between various forms, " favourable variations tend to be preserved, and unfavourable ones to be...destroyed. The result of this would be the formation of a new species." The idea must have come to him like a sudden flash of light that was, indeed, to illumine... | |
 | Benjamin Kidd - 1894 - Страниц: 396
...existence which everywhere goes on, from long continued observation of the habits of animals and plants, it at once struck me that, under these circumstances,...ones to be destroyed. The result of this would be the foundation of a new species. Here, then, I had at last got a theory by which to work. " — The Life... | |
 | W. T. B. Martin, T. E. S. T. - 1894 - Страниц: 536
...long-continued observation of the habits of animals and plants, it at once struck me that under . . . circumstances favourable variations would tend to...result of this would be the formation of new Species. But at that time I overlooked one problem of great importance. . . . This is the tendency in organic... | |
 | James Hutchison Stirling - 1894 - Страниц: 392
...naturally take place, and that was — by " the struggle for existence." It could be only so that " favourable variations would tend to be preserved, and unfavourable ones to be destroyed." " Here, then," says Mr. Darwin, " I had at last got a theory by which to work." In the struggle for... | |
 | George Boughton Curtiss - 1896 - Страниц: 910
...struck me that under these circumstances favorable variations would tend to be preserved and unfavorable ones to be destroyed. The result of this would be...Here, then, I had at last got a theory by which to work.1 The writings of Dr. Malthus exerted a wider influence in formulating the theoretical principles... | |
 | Edward Clodd - 1897 - Страниц: 284
...existence which everywhere goes on, from long-continued observations of the habits of plants and animals, it at once struck me that under these circumstances...would tend to be preserved, and unfavourable ones destroyed. The result of this would be the formation of new species. Shortly after his return he settled... | |
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I happened to read for amusement ' Malthus on Population, and being well prepared to appreciate the struggle for existence which everywhere goes on from long-continued observation of the habits of animals and plants, it at once struck me that under these... 
