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 7
... 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 from each other than do the individuals of any one ...
... 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 from each other than do the individuals of any one ...
Página 12
... look at the inheritance of every character whatever as the rule , and non - inheritance as the anomaly . The laws governing inheritance are quite unknown ; no one can say why a peculiarity in different individuals of the same species ...
... look at the inheritance of every character whatever as the rule , and non - inheritance as the anomaly . The laws governing inheritance are quite unknown ; no one can say why a peculiarity in different individuals of the same species ...
Página 14
... new characters thus arising shall be preserved . When we look to the hereditary varieties or races of our domestic animals and plants , and compare them with closely - allied species , we generally perceive in 14 ON THE ORIGIN OF SPECIES.
... new characters thus arising shall be preserved . When we look to the hereditary varieties or races of our domestic animals and plants , and compare them with closely - allied species , we generally perceive in 14 ON THE ORIGIN OF SPECIES.
Página 23
... look in vain throughout the whole great family of Columbidæ for a beak like that of the English carrier , or that of the short - faced tumbler , or barb ; for reversed feathers like those of the Jacobin ; for a crop like that of the ...
... look in vain throughout the whole great family of Columbidæ for a beak like that of the English carrier , or that of the short - faced tumbler , or barb ; for reversed feathers like those of the Jacobin ; for a crop like that of the ...
Página 28
... look further than to mere variability . We cannot suppose that all the breeds were suddenly produced as perfect and as useful as we now see them ; indeed , in several cases , we know that this has not been their history . The key is ...
... look further than to mere variability . We cannot suppose that all the breeds were suddenly produced as perfect and as useful as we now see them ; indeed , in several cases , we know that this has not been their history . The key is ...
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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