On the Origin of Species by Means of Natural Selection: Or The Preservation of Favoured Races in the Struggle for LifeHumphrey Milford, Oxford University Press, 1923 - 454 páginas |
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Página 26
... parent , as any naturalist could in coming to a similar conclusion in regard to the many species of finches , or other large groups of birds , in nature . One circumstance has struck me much ; namely , that all the breeders of the ...
... parent , as any naturalist could in coming to a similar conclusion in regard to the many species of finches , or other large groups of birds , in nature . One circumstance has struck me much ; namely , that all the breeders of the ...
Página 33
... parent Arab stock , so that the latter , by the regulations for the Goodwood Races , are favoured in the weights they carry . Lord Spencer and others have shown how the cattle of England have increased in weight and in early maturity ...
... parent Arab stock , so that the latter , by the regulations for the Goodwood Races , are favoured in the weights they carry . Lord Spencer and others have shown how the cattle of England have increased in weight and in early maturity ...
Página 34
... parent - stocks . No one would ever expect to get a first - rate heartsease or dahlia from the seed of a wild plant . No one would expect to raise a first - rate melting pear from the seed of the wild pear , though he might succeed from ...
... parent - stocks . No one would ever expect to get a first - rate heartsease or dahlia from the seed of a wild plant . No one would expect to raise a first - rate melting pear from the seed of the wild pear , though he might succeed from ...
Página 36
... parent bird of all fantails had only fourteen tail - feathers some- what expanded , like the present Java fantail , or like individuals of other and distinct breeds , in which as many as seventeen tail - feathers have been counted ...
... parent bird of all fantails had only fourteen tail - feathers some- what expanded , like the present Java fantail , or like individuals of other and distinct breeds , in which as many as seventeen tail - feathers have been counted ...
Página 46
... parents , and consequently must be ranked as varieties . Close investigation , in most cases , will bring natural- ists to an agreement how to rank doubtful forms . Yet it must be confessed that it is in the best - known countries that ...
... parents , and consequently must be ranked as varieties . Close investigation , in most cases , will bring natural- ists to an agreement how to rank doubtful forms . Yet it must be confessed that it is in the best - known countries that ...
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Términos y frases comunes
accumulated adapted affinities allied species America amount analogous ancient appear Archipelago become bees believe birds breeds cause cells characters cirripedes climate closely allied colour common parent continuous crossed crustaceans degree difficulty distinct species divergence doubt embryo endemic Europe existing exterminated extinct extremely facts favourable fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period gradations greater number groups of species habits Hence hermaphrodites hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing land larvæ less living male mammals manner Marsupials migration modification modified descendants natural selection naturalists nearly nest oceanic islands offspring organisation perfect pigeons pistil plants pollen present principle probably produced progenitor ranked reciprocal crosses remarked resemble rock-pigeon rudimentary organs seeds sexual selection Silurian slight South America sterility structure struggle successive suppose swimbladder tend theory tion trees variability variation vary whole widely