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
... marked races of some other domes- ticated species , there is presumptive or even strong evidence , that all are descended from a single wild stock . It has often been assumed that man has chosen for domestication animals and plants ...
... marked races of some other domes- ticated species , there is presumptive or even strong evidence , that all are descended from a single wild stock . It has often been assumed that man has chosen for domestication animals and plants ...
Página 29
... marked like the rock - pigeon , although no other existing species is thus coloured and marked , so that in each separate breed there might be a tendency to revert to the very same colours and markings . Or , secondly , that each breed ...
... marked like the rock - pigeon , although no other existing species is thus coloured and marked , so that in each separate breed there might be a tendency to revert to the very same colours and markings . Or , secondly , that each breed ...
Página 36
... marked and classed , so that the very best may ultimately be selected for breeding . What English breeders have actually effected is proved by the enormous prices given for animals with a good pedigree ; and these have been exported to ...
... marked and classed , so that the very best may ultimately be selected for breeding . What English breeders have actually effected is proved by the enormous prices given for animals with a good pedigree ; and these have been exported to ...
Página 45
... marked varieties ; hence the Toulouse and the common breed , which differ only in colour , that most fleeting of characters , have lately been exhibited as distinct at our poultry - shows . These views appear to explain what has ...
... marked varieties ; hence the Toulouse and the common breed , which differ only in colour , that most fleeting of characters , have lately been exhibited as distinct at our poultry - shows . These views appear to explain what has ...
Página 57
... marked and well - known varieties can be named which have not been ranked as species by at least some com- petent judges . That varieties of this doubtful nature are far from uncommon cannot be disputed . Compare the several floras of ...
... marked and well - known varieties can be named which have not been ranked as species by at least some com- petent judges . That varieties of this doubtful nature are far from uncommon cannot be disputed . Compare the several floras 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