On the Origin of Species by Means of Natural Selection: Or The Preservation of Favored Races in the Struggle for Life, Volumen2D. Appleton, 1888 - 458 páginas |
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Página xv
... certain characters alone . After remarking that negroes and mulattoes enjoy an immunity from certain tropical diseases , he observes , firstly , that all animals tend to vary in some degree , and , secondly , that agriculturists improve ...
... certain characters alone . After remarking that negroes and mulattoes enjoy an immunity from certain tropical diseases , he observes , firstly , that all animals tend to vary in some degree , and , secondly , that agriculturists improve ...
Página 2
... certain trees , which has seeds that must be transported by certain birds , and which has flowers with separate sexes absolutely requiring the agency of certain . insects to bring pollen from one flower to the other , it is equally ...
... certain trees , which has seeds that must be transported by certain birds , and which has flowers with separate sexes absolutely requiring the agency of certain . insects to bring pollen from one flower to the other , it is equally ...
Página 10
... certain characters to its grandfather or grandmother or more remote ances- tor ; why a peculiarity is often transmitted from one sex to both sexes , or to one sex alone , more commonly but not exclusively to the like sex . It is a fact ...
... certain characters to its grandfather or grandmother or more remote ances- tor ; why a peculiarity is often transmitted from one sex to both sexes , or to one sex alone , more commonly but not exclusively to the like sex . It is a fact ...
Página 14
... certain that they are descended from a different aboriginal stock from our European cattle ; and some competent judges believe that these latter lave had two or three wild progenitors , —whether or not these deserve to be called species ...
... certain that they are descended from a different aboriginal stock from our European cattle ; and some competent judges believe that these latter lave had two or three wild progenitors , —whether or not these deserve to be called species ...
Página 17
... certain breeds , the males and females have come to differ in a slight degree from each other . Altogether at least a score of pigeons might be chosen , which , if shown to an ornithologist , and he were told that they were wild birds ...
... certain breeds , the males and females have come to differ in a slight degree from each other . Altogether at least a score of pigeons might be chosen , which , if shown to an ornithologist , and he were told that they were wild birds ...
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Términos y frases comunes
adapted admit affinities allied species America analogous ancient appear Asa Gray beak become bees believe belonging birds breeds cause cells characters climate closely allied colour continued crossed crustaceans degree developed difficulty distinct species doubt effects eggs embryo existing extinct extremely facts favourable fertilised fertility flowers formation formerly forms fossil Fritz Müller genera genus geological geological period Glacial period gradations greater number habits Hence hybrids important individuals inhabitants inherited insects instance instincts intercrossing intermediate kind lamellæ larvæ less living male mammals manner Marsupials migration modified descendants natural selection naturalists nearly nest occasionally occur oceanic islands offspring organisation organs parent peculiar perfect pigeon pistil pollen present preserved principle probably produced quadrupeds ranked reciprocal crosses remarked reproductive resemblance rudimentary seeds sexual selection slight South America stamens sterility structure struggle successive supposed tend theory tion variability variations varieties vary whilst whole wings young