The Origin of Species by Means of Natural Selection: Or the Preservation of Favored Races in the Struggle for LifeD. Appleton, 1904 - 435 páginas |
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Página 13
... Important changes in the embryo or larva will probably entail changes in the mature animal . In monstrosities , the correlations between quite distinct parts are very curious ; and many instances are given in Isidore Geoffroy St ...
... Important changes in the embryo or larva will probably entail changes in the mature animal . In monstrosities , the correlations between quite distinct parts are very curious ; and many instances are given in Isidore Geoffroy St ...
Página 15
... importance to us , that peculiarities appearing in the males of our domestic breeds are often trans- mitted , either exclusively or in a much greater degree , to the males alone . A much more important rule , which I think may be ...
... importance to us , that peculiarities appearing in the males of our domestic breeds are often trans- mitted , either exclusively or in a much greater degree , to the males alone . A much more important rule , which I think may be ...
Página 24
... important , as being of considerable antiquity . I have associated with several eminent fanciers , and have been permitted to join two of the London Pigeon Clubs . The diversity of the ! breeds is something astonishing . Compare the ...
... important , as being of considerable antiquity . I have associated with several eminent fanciers , and have been permitted to join two of the London Pigeon Clubs . The diversity of the ! breeds is something astonishing . Compare the ...
Página 38
... important . But it is very far from true that the principle is a modern discovery . I could give several references to works of high antiquity , in which the full importance of the principle is acknowledged . In rude and barbarous ...
... important . But it is very far from true that the principle is a modern discovery . I could give several references to works of high antiquity , in which the full importance of the principle is acknowledged . In rude and barbarous ...
Página 39
... important . Thus , a man who intends keeping pointers . naturally tries to get as good dogs as he can , and after- wards breeds from his own best dogs , but he has no wish or expectation of permanently altering the breed . Nevertheless ...
... important . Thus , a man who intends keeping pointers . naturally tries to get as good dogs as he can , and after- wards breeds from his own best dogs , but he has no wish or expectation of permanently altering the breed . Nevertheless ...
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Términos y frases comunes
adapted affinities allied species America ancient appear Asa Gray beak become bees believe belonging birds breeds cause cells characters climate closely allied colour common continent crossed crustaceans degree developed difficulty distinct species domestic doubt effects eggs embryo existing extinct extremely facts favourable fertilised fertility flowers formation forms fossil Fritz Müller genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hybrids important individuals inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ larvæ less living males mammals manner marsupials migration modified descendants natural selection naturalists nearly nest occasionally offspring organisation organs parent peculiar perfect pigeon pistil pollen present principle probably produced progenitor quadrupeds ranked remarked resemblance rudimentary seeds sexual selection Silurian slight South America stamens sterility structure successive supposed swimbladder tend theory tion trees variability variations varieties vary whilst whole wings young