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 xxii
... observation des animaux sauvages démontre déjà la variabilité limitée des espèces . Les expériences sur les animaux sauvages , devenus domestiques , et sur les animaux domestiques redevenus sauvages , la démon- trent plus clairement ...
... observation des animaux sauvages démontre déjà la variabilité limitée des espèces . Les expériences sur les animaux sauvages , devenus domestiques , et sur les animaux domestiques redevenus sauvages , la démon- trent plus clairement ...
Página xxvi
... many original observations . The first edition of this work was published on No- vember 24th , 1859 , and the second edition on January 7th , 1860 . ORIGIN OF SPECIES . INTRODUCTION . WHEN on board H.M.S.. xxvi HISTORICAL SKETCH .
... many original observations . The first edition of this work was published on No- vember 24th , 1859 , and the second edition on January 7th , 1860 . ORIGIN OF SPECIES . INTRODUCTION . WHEN on board H.M.S.. xxvi HISTORICAL SKETCH .
Página 4
... observations . it seemed to me probable that a careful study of domes- ticated animals and of cultivated plants would offer the best chance of making out this obscure problem . Nor have I been disappointed ; in this and in all other per ...
... observations . it seemed to me probable that a careful study of domes- ticated animals and of cultivated plants would offer the best chance of making out this obscure problem . Nor have I been disappointed ; in this and in all other per ...
Página 10
... observed with plants and ani- mals when reared under new or unnatural condi- tions . Many facts clearly show how eminently sus- ceptible the reproductive system is to very slight changes in the surrounding conditions . Nothing is more ...
... observed with plants and ani- mals when reared under new or unnatural condi- tions . Many facts clearly show how eminently sus- ceptible the reproductive system is to very slight changes in the surrounding conditions . Nothing is more ...
Página 30
... observations , purposely made , on the most distinct breeds . Now , hardly any cases have been ascertained with certainty of hybrids from two quite distinct species of animals being perfectly fertile . Some authors believe that long ...
... observations , purposely made , on the most distinct breeds . Now , hardly any cases have been ascertained with certainty of hybrids from two quite distinct species of animals being perfectly fertile . Some authors believe that long ...
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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