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 26
... supposed aboriginal stocks must all have been rock - pigeons , that is , they did not breed or willingly perch on trees . But besides C. livia , with its geographical sub - species , only two or three other species of rock - pigeons are ...
... supposed aboriginal stocks must all have been rock - pigeons , that is , they did not breed or willingly perch on trees . But besides C. livia , with its geographical sub - species , only two or three other species of rock - pigeons are ...
Página 27
... supposed aboriginal stocks must either still exist in the countries where they were originally domesticated , and yet be unknown to ornithologists ; and this , considering their size , habits , and remarkable characters , seems ...
... supposed aboriginal stocks must either still exist in the countries where they were originally domesticated , and yet be unknown to ornithologists ; and this , considering their size , habits , and remarkable characters , seems ...
Página 30
... supposed species of pigeons to breed freely under do- mestication ; these supposed species being quite un- known in a wild state , and their not having become anywhere feral ; -these species presenting certain very abnormal characters ...
... supposed species of pigeons to breed freely under do- mestication ; these supposed species being quite un- known in a wild state , and their not having become anywhere feral ; -these species presenting certain very abnormal characters ...
Página 52
... supposed not to be inherited ; but who can say that the dwarfed condition of shells in the brackish waters of the Baltic , or dwarfed plants on Al- pine summits , or the thicker fur of an animal from far northwards , would not in some ...
... supposed not to be inherited ; but who can say that the dwarfed condition of shells in the brackish waters of the Baltic , or dwarfed plants on Al- pine summits , or the thicker fur of an animal from far northwards , would not in some ...
Página 60
... supposed would freely intercross , as varieties ; and those which appear to have lost this power , as species . As the differences depend on the insects having long fed on distinct plants , it cannot be expected that in- termediate ...
... supposed would freely intercross , as varieties ; and those which appear to have lost this power , as species . As the differences depend on the insects having long fed on distinct plants , it cannot be expected that in- termediate ...
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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