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 123
... characters our present subject . It is notorious that specific characters are more more variable than generic characters variable than generic . To explain by a simple example what is meant : if in a large genus of plants some species ...
... characters our present subject . It is notorious that specific characters are more more variable than generic characters variable than generic . To explain by a simple example what is meant : if in a large genus of plants some species ...
Página 124
... characters may be attributed to inheritance from a common progenitor , for it can rarely have happened that natural selection will have modified several distinct species , fitted to more or less widely- different habits , in exactly the ...
... characters may be attributed to inheritance from a common progenitor , for it can rarely have happened that natural selection will have modified several distinct species , fitted to more or less widely- different habits , in exactly the ...
Página 128
... characters another and distinct species , this other species being , according to our view , only a well- marked and permanent variety . But characters exclusively due to analogous variation would probably be of an unimportant nature ...
... characters another and distinct species , this other species being , according to our view , only a well- marked and permanent variety . But characters exclusively due to analogous variation would probably be of an unimportant nature ...
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