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 8
... race , as already remarked , less between varieties uniformity of character than in true species . Domestic races often have and species ; a somewhat monstrous character ; by which I mean , that , although Origin of domestic differing ...
... race , as already remarked , less between varieties uniformity of character than in true species . Domestic races often have and species ; a somewhat monstrous character ; by which I mean , that , although Origin of domestic differing ...
Página 11
... races by crossing has been greatly exaggerated . Many cases are on record , showing that a race may be modified by occasional crosses , if aided by the careful selection of the individuals which present the desired character ; but to ...
... races by crossing has been greatly exaggerated . Many cases are on record , showing that a race may be modified by occasional crosses , if aided by the careful selection of the individuals which present the desired character ; but to ...
Página 18
... races ; and though they well know that each race varies slightly , for they win their prizes by selecting such slight differences , yet they ignore all general arguments , and refuse to sum up in their minds slight differences ...
... races ; and though they well know that each race varies slightly , for they win their prizes by selecting such slight differences , yet they ignore all general arguments , and refuse to sum up in their minds slight differences ...
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