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 4
... favourable to variation . In the next chapter the Struggle for Existence amongst all organic beings throughout the world , which inevitably follows from the high geo- metrical ratio of their increase , will be treated of . This is the ...
... favourable to variation . In the next chapter the Struggle for Existence amongst all organic beings throughout the world , which inevitably follows from the high geo- metrical ratio of their increase , will be treated of . This is the ...
Página 7
... favourable to Man's power of Selection . WHEN we look to the individuals of the same variety or sub - variety of our older cultivated plants and animals , one of the first points which strikes us is , that they generally differ more ...
... favourable to Man's power of Selection . WHEN we look to the individuals of the same variety or sub - variety of our older cultivated plants and animals , one of the first points which strikes us is , that they generally differ more ...
Página 26
... favourable circumstance for the production of distinct breeds , that male and female pigeons can be easily mated for life ; and thus different breeds can be kept together in the same aviary . I have discussed the probable origin of ...
... favourable circumstance for the production of distinct breeds , that male and female pigeons can be easily mated for life ; and thus different breeds can be kept together in the same aviary . I have discussed the probable origin of ...
Página 37
... favourable or the reverse , to man's power of selection . A high degree of variability is obviously favourable , as freely giving the materials for selection to work on ; not that mere individual differences are not amply sufficient ...
... favourable or the reverse , to man's power of selection . A high degree of variability is obviously favourable , as freely giving the materials for selection to work on ; not that mere individual differences are not amply sufficient ...
Página 38
... favourable conditions of life , so as to breed freely in that country . When the individuals of any species are scanty , all the individuals , whatever their quality may be , will generally be allowed to breed , and this will ...
... favourable conditions of life , so as to breed freely in that country . When the individuals of any species are scanty , all the individuals , whatever their quality may be , will generally be allowed to breed , and this will ...
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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