On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for LifeEaston Press, 1976 - 470 páginas |
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Página 63
... preserved . How fleeting are the wishes and efforts of man ! how short his time ! and consequently how poor will be his results , compared with those accumulated by Nature during whole geological periods ! Can we wonder , then , that ...
... preserved . How fleeting are the wishes and efforts of man ! how short his time ! and consequently how poor will be his results , compared with those accumulated by Nature during whole geological periods ! Can we wonder , then , that ...
Página 69
... preservation in a state of nature of any occasional deviation of structure , such as a monstrosity , would be a rare event ; and that , if at first preserved , it would generally be lost by subsequent intercrossing with ordinary ...
... preservation in a state of nature of any occasional deviation of structure , such as a monstrosity , would be a rare event ; and that , if at first preserved , it would generally be lost by subsequent intercrossing with ordinary ...
Página 427
... preserved and accumulated through natural selection , or the survival of the fittest ? If man can by patience select variations useful to him , why , under changing and complex conditions of life , should not variations useful to ...
... preserved and accumulated through natural selection , or the survival of the fittest ? If man can by patience select variations useful to him , why , under changing and complex conditions of life , should not variations useful to ...
Contenido
VARIATION UNDER NATURE | 30 |
STRUGGLE FOR EXISTENCE | 45 |
NATURAL SELECTION | 59 |
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Términos y frases comunes
accumulated adapted admit affinities allied species America ancient appear beak become bees believe belonging birds breeds cause cells characters climate closely allied colour common progenitor continuous crossed crustaceans degree developed difficulty distinct species divergence doubt effects eggs embryo existing exterminated extinct extremely facts favourable fertilised fertility flowers formation forms fossil Fritz Müller genera genus geological geological period gradations greater number groups of species habits Hence hybrids hybrids produced 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 offspring organisation organs Origin of Species parent peculiar perfect pigeons pistil plants pollen present preserved principle probably produced quadrupeds ranked reciprocal crosses remarked resemblance rudimentary seeds slight South America stamens sterility structure struggle successive supposed swimbladder theory variability variations varieties vary whilst whole wings young