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 4
... naturalists until recently entertained , and which I formerly entertained - namely , that each species has been independently created - is erroneous . I am fully convinced that species are not immutable ; but that those belonging to ...
... naturalists until recently entertained , and which I formerly entertained - namely , that each species has been independently created - is erroneous . I am fully convinced that species are not immutable ; but that those belonging to ...
Página 7
... naturalists have maintained that all variations are con- nected with the act of sexual reproduction ; but this is certainly an error ; for I have given in another work a long list of " sporting plants , " as they are called by gardeners ...
... naturalists have maintained that all variations are con- nected with the act of sexual reproduction ; but this is certainly an error ; for I have given in another work a long list of " sporting plants , " as they are called by gardeners ...
Página 10
... naturalists - namely , that our domestic varieties , when run wild , gradually but invariably revert in cha- racter to their aboriginal stocks . Hence it has been argued that no deductions can be drawn from domestic races to species in ...
... naturalists - namely , that our domestic varieties , when run wild , gradually but invariably revert in cha- racter to their aboriginal stocks . Hence it has been argued that no deductions can be drawn from domestic races to species in ...
Página 11
... been stated that domestic races do not differ from each other in characters of generic value . It can be shown that this statement is not correct ; but naturalists differ much in. CHAP . I. ] 11 CHARACTER OF DOMESTIC VARIETIES .
... been stated that domestic races do not differ from each other in characters of generic value . It can be shown that this statement is not correct ; but naturalists differ much in. CHAP . I. ] 11 CHARACTER OF DOMESTIC VARIETIES .
Página 12
... naturalists differ much in determining what characters are of generic value ; all such valuations being at present empirical . When it is explained how genera originate under nature , it will be seen that we have no right to expect ...
... naturalists differ much in determining what characters are of generic value ; all such valuations being at present empirical . When it is explained how genera originate under nature , it will be seen that we have no right to expect ...
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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