The Origin of Species by Means of Natural Selection: Or, the Preservation of Favored Races in the Struggle for Life, Volumen1D. Appleton, 1898 |
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Página 20
... remarked , that they had at this early age progressed considerably in civilisation ; and this again implies a long continued previous period of less advanced civilisation , during which the. 20 CHARACTER OF DOMESTIC VARIETIES . [ CHAP . I.
... remarked , that they had at this early age progressed considerably in civilisation ; and this again implies a long continued previous period of less advanced civilisation , during which the. 20 CHARACTER OF DOMESTIC VARIETIES . [ CHAP . I.
Página 30
... continued domestication eliminates this strong tendency to sterility in species . From the history of the dog , and of some other domestic animals , this conclusion is probably quite correct , if applied to species closely related to ...
... continued domestication eliminates this strong tendency to sterility in species . From the history of the dog , and of some other domestic animals , this conclusion is probably quite correct , if applied to species closely related to ...
Página 33
... continued . study they are strongly impressed with the differences between the several races ; and though they well know that each race varies slightly , for they win their prizes by selecting such slight differences , yet they ignore ...
... continued . study they are strongly impressed with the differences between the several races ; and though they well know that each race varies slightly , for they win their prizes by selecting such slight differences , yet they ignore ...
Página 38
... continued selection of slight variations , either in the leaves , the flowers , or the fruit , will produce races differing from each other chiefly in these characters . It may be objected that the principle of selection has been ...
... continued selection of slight variations , either in the leaves , the flowers , or the fruit , will produce races differing from each other chiefly in these characters . It may be objected that the principle of selection has been ...
Página 39
... continued during centuries , would improve and modify any breed , in the same way as Bakewell , Collins , & c . , by this very same process , only carried on more methodically , did greatly modify , even during their lifetimes , the ...
... continued during centuries , would improve and modify any breed , in the same way as Bakewell , Collins , & c . , by this very same process , only carried on more methodically , did greatly modify , even during their lifetimes , the ...
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Términos y frases comunes
adapted advantage allied analogous animals and plants appear Asa Gray beak become bees believe birds breeds caudicle cause cells characters climate closely colour common crossed cuckoo degree descendants developed difficulty distinct species disuse divergence domestic animals domestic races doubt effects eggs existence extinct extremely facts favourable females flowers forms Fritz Müller genera genus giraffe gradations greater number groups habits Hence hermaphrodites hive-bee important increase inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ large number larger genera larvæ less males manner Melipona Mivart modified natural selection naturalists nearly nest occasionally offspring organisation organs origin Origin of Species parent perfect period pigeons pollen pollen-grains present preserved prey principle probably produced progenitor quadrupeds rank rarely Red Grouse relation remarked resemble rock-pigeon seeds sexes sexual selection slight stamens striped structure struggle supposed swimbladder tend tendency tion tree variability variations varieties vary widely wings young