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 19
... kind truly , were the offspring of any single species , then such facts would have great weight in making us doubt about the immutability of the many closely allied natural species - for instance , of the many foxes - inhabiting ...
... kind truly , were the offspring of any single species , then such facts would have great weight in making us doubt about the immutability of the many closely allied natural species - for instance , of the many foxes - inhabiting ...
Página 37
... kind of selection is , in fact , likewise followed ; for hardly any one is so careless as to breed from his worst animals . In regard to plants , there is another means of ob- serving the accumulated effects of selection - namely , by ...
... kind of selection is , in fact , likewise followed ; for hardly any one is so careless as to breed from his worst animals . In regard to plants , there is another means of ob- serving the accumulated effects of selection - namely , by ...
Página 39
... kind in the country . But , for our purpose , a form of Selection , which may be called Unconscious , and which results from every one trying to possess and breed from the best individual animals , is more important . Thus , a man who ...
... kind in the country . But , for our purpose , a form of Selection , which may be called Unconscious , and which results from every one trying to possess and breed from the best individual animals , is more important . Thus , a man who ...
Página 40
... kind can never be recognised unless actual measurements or careful drawings of the breeds in question have been made long ago , which may serve for comparison . In some cases , however , unchanged , or but little changed individuals of ...
... kind can never be recognised unless actual measurements or careful drawings of the breeds in question have been made long ago , which may serve for comparison . In some cases , however , unchanged , or but little changed individuals of ...
Página 41
... kind of unconscious selection going on . We see the value set on animals even by the barbarians of Tierra del Fuego , by their killing and devouring their old women , in times of dearth , as of less value than their dogs . In plants the ...
... kind of unconscious selection going on . We see the value set on animals even by the barbarians of Tierra del Fuego , by their killing and devouring their old women , in times of dearth , as of less value than their dogs . In plants 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