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 133
... developed to an extraordinary size or in an extraordinary manner , in comparison with the same part or organ in the allied species , must have gone through an extraordinary amount of modifi- cation since the genus arose ; and thus we ...
... developed to an extraordinary size or in an extraordinary manner , in comparison with the same part or organ in the allied species , must have gone through an extraordinary amount of modifi- cation since the genus arose ; and thus we ...
Página 200
... developed from the lips of the cells , without having passed through the avicularian stage ; but it seems more probable that they have passed through this stage , as during the early stages of the transformation , the other parts of the ...
... developed from the lips of the cells , without having passed through the avicularian stage ; but it seems more probable that they have passed through this stage , as during the early stages of the transformation , the other parts of the ...
Página 412
... developed , unless we have reason to suppose that they were formerly more highly developed , ought not to be considered as rudimentary . They may be in a nascent condition , and in progress towards further development . Rudimentary ...
... developed , unless we have reason to suppose that they were formerly more highly developed , ought not to be considered as rudimentary . They may be in a nascent condition , and in progress towards further development . Rudimentary ...
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