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 35
... important part which selection by man has played , it becomes at once obvious how it is that our domestic races show adapta- tion in their structure or in their habits to man's wants or fancies . We can , I think , further understand ...
... important part which selection by man has played , it becomes at once obvious how it is that our domestic races show adapta- tion in their structure or in their habits to man's wants or fancies . We can , I think , further understand ...
Página 38
... important point of all is , that the animal or plant should be so highly useful to man , or so much valued by him , that the closest attention should be paid to even the slightest deviation in the qualities or structure of each ...
... important point of all is , that the animal or plant should be so highly useful to man , or so much valued by him , that the closest attention should be paid to even the slightest deviation in the qualities or structure of each ...
Página 39
... importance as causing variability . I do not believe that variability is an inherent and necessary contingency , under ... important part in the origin of our domestic productions . When in any country several domestic breeds have once ...
... importance as causing variability . I do not believe that variability is an inherent and necessary contingency , under ... important part in the origin of our domestic productions . When in any country several domestic breeds have once ...
Página 40
... importance of the crossing of varieties has , I believe , been greatly exaggerated , both in regard to animals and to those plants which are propagated by seed . In plants which are temporarily propagated by cuttings , buds , etc. , the ...
... importance of the crossing of varieties has , I believe , been greatly exaggerated , both in regard to animals and to those plants which are propagated by seed . In plants which are temporarily propagated by cuttings , buds , etc. , the ...
Página 42
... important for us , as they afford materials for natural selection to accumulate , in the same manner as man can accumu- late in any given direction individual differences in his domesticated productions . These individual differences ...
... important for us , as they afford materials for natural selection to accumulate , in the same manner as man can accumu- late in any given direction individual differences in his domesticated productions . These individual differences ...
Otras ediciones - Ver todas
On the Origin of Species by Means of Natural Selection: or the Preservation ... Charles Darwin Vista previa limitada - 2023 |
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