On the Origin of Species by Means of Natural Selection: Or The Preservation of Favored Races in the Struggle for Life, Volumen2D. Appleton, 1888 - 458 páginas |
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Página 12
... closely allied species , we generally perceive in each domestic race , as already remarked , less uniformity of character than in true species . Domestic races often have a somewhat monstrous character ; by which I mean , that ...
... closely allied species , we generally perceive in each domestic race , as already remarked , less uniformity of character than in true species . Domestic races often have a somewhat monstrous character ; by which I mean , that ...
Página 13
... closely resemble , or are even identical with , those still exist- ing . But this only throws far backwards the history of civilisation , and shows that animals were domesticated at a much earlier period than has hitherto been supposed ...
... closely resemble , or are even identical with , those still exist- ing . But this only throws far backwards the history of civilisation , and shows that animals were domesticated at a much earlier period than has hitherto been supposed ...
Página 19
... closely related to each other . But to extend it so far as to suppose that species , aborigi- nally as distinct as carriers , tumblers , pouters , and fantails now are , should yield offspring perfectly fertile inter se , would be rash ...
... closely related to each other . But to extend it so far as to suppose that species , aborigi- nally as distinct as carriers , tumblers , pouters , and fantails now are , should yield offspring perfectly fertile inter se , would be rash ...
Página 23
... closely allied sub - breeds . And when a cross has been made , the closest selection is far more indispensable even than in ordinary cases . If selection consisted merely in sepa- rating some very distinct variety , and breeding from it ...
... closely allied sub - breeds . And when a cross has been made , the closest selection is far more indispensable even than in ordinary cases . If selection consisted merely in sepa- rating some very distinct variety , and breeding from it ...
Página 33
... closely , but unequally , related to each other , and in having restricted ranges . - BEFORE applying the principles arrived at in the last chapter to organic beings in a state of nature , we must briefly discuss whether these latter ...
... closely , but unequally , related to each other , and in having restricted ranges . - BEFORE applying the principles arrived at in the last chapter to organic beings in a state of nature , we must briefly discuss whether these latter ...
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Términos y frases comunes
adapted admit affinities allied species America analogous ancient appear Asa Gray beak become bees believe belonging birds breeds cause cells characters climate closely allied colour continued crossed crustaceans degree developed difficulty distinct species doubt effects eggs embryo existing extinct extremely facts favourable fertilised fertility flowers formation formerly forms fossil Fritz Müller genera genus geological geological period Glacial period gradations greater number habits Hence hybrids important 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 reproductive resemblance rudimentary seeds sexual selection slight South America stamens sterility structure struggle successive supposed tend theory tion variability variations varieties vary whilst whole wings young