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 9
... variability is a much more common result of changed conditions than definite variability , and has probably played a more important part in the forma- tion of our domestic races . We see indefinite vari- ability in the endless slight ...
... variability is a much more common result of changed conditions than definite variability , and has probably played a more important part in the forma- tion of our domestic races . We see indefinite vari- ability in the endless slight ...
Página 10
... variability is thus induced , partly from the fact of this system being extremely sensitive to any change in the conditions , and partly from the similarity , as Kölreuter and others have remarked , between the variability which follows ...
... variability is thus induced , partly from the fact of this system being extremely sensitive to any change in the conditions , and partly from the similarity , as Kölreuter and others have remarked , between the variability which follows ...
Página 20
... variability of the ass and goose , or the small power of endurance of warmth by the reindeer , or of cold by the common camel , prevented their domestication ? I cannot doubt that if other animals and plants , equal in number to our ...
... variability of the ass and goose , or the small power of endurance of warmth by the reindeer , or of cold by the common camel , prevented their domestication ? I cannot doubt that if other animals and plants , equal in number to our ...
Página 35
... variability . We cannot suppose that all the breeds . were suddenly produced as perfect and as useful as we now see them ; indeed , in many cases , we know that this has not been their history . The key is man's power of accumulative ...
... variability . We cannot suppose that all the breeds . were suddenly produced as perfect and as useful as we now see them ; indeed , in many cases , we know that this has not been their history . The key is man's power of accumulative ...
Página 46
... variability is obviously favourable , as freely giving the materials for selection to work on ; not that mere individual differences are not amply sufficient , with extreme care , to allow of the accumula- tion of a large amount of ...
... variability is obviously favourable , as freely giving the materials for selection to work on ; not that mere individual differences are not amply sufficient , with extreme care , to allow of the accumula- tion of a large amount of ...
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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