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 3
... sometimes varying conditions of life , will have a better chance of surviving , and thus be naturally selected . From the strong principle of inheritance , any selected variety will tend to propagate its new and modified form . This ...
... sometimes varying conditions of life , will have a better chance of surviving , and thus be naturally selected . From the strong principle of inheritance , any selected variety will tend to propagate its new and modified form . This ...
Página 6
... sometimes arise under , as far as we can judge , dissimilar conditions ; and , on the other hand , dissimila variations arise under conditions which appear to be nearly uniform . The effects on the offspring are either definite or ...
... sometimes arise under , as far as we can judge , dissimilar conditions ; and , on the other hand , dissimila variations arise under conditions which appear to be nearly uniform . The effects on the offspring are either definite or ...
Página 8
... sometimes widely different character from that of the other buds on the same plant . These bud variations , as they may be named , can be pro- pagated by grafts , offsets , & c . , and sometimes by seed . They occur rarely under nature ...
... sometimes widely different character from that of the other buds on the same plant . These bud variations , as they may be named , can be pro- pagated by grafts , offsets , & c . , and sometimes by seed . They occur rarely under nature ...
Página 10
... sometimes inherited and sometimes not so ; why the child often reverts in certain characters to its grandfather or grandmother or more remote ances- tor ; why a peculiarity is often transmitted from one sex to both sexes , or to one sex ...
... sometimes inherited and sometimes not so ; why the child often reverts in certain characters to its grandfather or grandmother or more remote ances- tor ; why a peculiarity is often transmitted from one sex to both sexes , or to one sex ...
Página 15
... sometimes ( as I have found with pigeons ) quite uniform in character , and everything seems simple enough ; but when these mongrels are crossed one with another for several generations , hardly two of them are alike , and then the ...
... sometimes ( as I have found with pigeons ) quite uniform in character , and everything seems simple enough ; but when these mongrels are crossed one with another for several generations , hardly two of them are alike , and then the ...
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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