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 5
... varieties when intercrossed ; and fourthly , the imperfection of the Geological Record . In the next chapter I shall consider the geological succession of organic beings throughout time ; in the eleventh and twelfth , their geographical ...
... varieties when intercrossed ; and fourthly , the imperfection of the Geological Record . In the next chapter I shall consider the geological succession of organic beings throughout time ; in the eleventh and twelfth , their geographical ...
Página 7
... Varieties -- Difficulty of dis tinguishing between Varieties and Species - Origin of Domestic Varieties from one or more Species - Domestic Pigeons , their Differences and Origin - Principle of Selection anciently followed , its Effects ...
... Varieties -- Difficulty of dis tinguishing between Varieties and Species - Origin of Domestic Varieties from one or more Species - Domestic Pigeons , their Differences and Origin - Principle of Selection anciently followed , its Effects ...
Página 8
... varieties : our oldest domesticated animals are still capable of rapid improvement or modification . It has been disputed at what period of life the causes of variability , whatever they may be , generally act ; whether during the early ...
... varieties : our oldest domesticated animals are still capable of rapid improvement or modification . It has been disputed at what period of life the causes of variability , whatever they may be , generally act ; whether during the early ...
Página 12
... varieties and sub - varieties differ slightly from each other . The whole organisation seems to have become plastic , and tends to depart in some small degree from that of the parental type . Any variation which is not inherited is ...
... varieties and sub - varieties differ slightly from each other . The whole organisation seems to have become plastic , and tends to depart in some small degree from that of the parental type . Any variation which is not inherited is ...
Página 14
... varieties could not possibly live in a wild state . In many cases we do not know what the aboriginal stock was , and so could not tell whether or not nearly perfect reversion had ensued . It would be quite necessary , in order to ...
... varieties could not possibly live in a wild state . In many cases we do not know what the aboriginal stock was , and so could not tell whether or not nearly perfect reversion had ensued . It would be quite necessary , in order to ...
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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