The Origin of Species by Means of Natural Selection,: Or the Preservation of Favoured Races in the Struggle for LifeJohn Murray, Albemarle Street., 1891 - 432 páginas |
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Página xxi
... existing species a hypothesis which , though unproven , and sadly damaged by some of its sup- porters , is yet the only one to which physiology lends any counte- nance ; their existence would seem to show that the amount of modification ...
... existing species a hypothesis which , though unproven , and sadly damaged by some of its sup- porters , is yet the only one to which physiology lends any counte- nance ; their existence would seem to show that the amount of modification ...
Página 12
... existing domesticated productions have varied . In the case of most of our anciently domesticated animals and plants , it is not possible to come to any definite conclusion , whether they are descended from one or several wild species ...
... existing domesticated productions have varied . In the case of most of our anciently domesticated animals and plants , it is not possible to come to any definite conclusion , whether they are descended from one or several wild species ...
Página 18
... existing species is thus coloured and marked , so that in each separate breed there might be a tendency to revert to the very same colours and markings . Or , secondly , that each breed , even the purest , has within a dozen , or at ...
... existing species is thus coloured and marked , so that in each separate breed there might be a tendency to revert to the very same colours and markings . Or , secondly , that each breed , even the purest , has within a dozen , or at ...
Página 25
... existing in the mind of any one at all acquainted with the subject , that the owner of either of them has deviated in any one instance from the pure blood of Mr. Bakewell's flock , and yet the difference between the sheep possessed by ...
... existing in the mind of any one at all acquainted with the subject , that the owner of either of them has deviated in any one instance from the pure blood of Mr. Bakewell's flock , and yet the difference between the sheep possessed by ...
Página 67
... existing conditions remained the same , a still stronger tendency to vary in the same manner . There can also be little doubt that the tendency to vary in the same manner has often been so strong that all the individuals of the same ...
... existing conditions remained the same , a still stronger tendency to vary in the same manner . There can also be little doubt that the tendency to vary in the same manner has often been so strong that all the individuals of the same ...
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Términos y frases comunes
accumulated adapted admit affinities allied species America analogous ancient appear beak become bees believe belonging birds breeds cause cells characters climate closely allied colour continued crossed crustaceans degree developed difficulty distinct species domestic animals doubt effects eggs embryo existing extinct extremely facts favourable female fertilised fertility flowers formation formerly forms fossil Fritz Müller genera genus geological geological period Glacial period gradations greater number habits Hence hybrids important increase individuals inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ larvæ less living male mammals manner Marsupials migration modified descendants natural selection naturalists nearly nest occasionally occur oceanic islands offspring organisation organs parent peculiar perfect pigeon pistil pollen present preserved principle probably produced quadrupeds ranked reciprocal crosses remarked resemblance rudimentary seeds sexual selection Silurian slight South America stamens sterility structure successive supposed tend theory tion variability variations varieties vary whilst whole wings young