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
... organic beings throughout time ; in the eleventh and twelfth , their geographical distribution throughout space ; in the thirteenth , their classification or mutual affinities , both when mature and in an embryonic condition . In the ...
... organic beings throughout time ; in the eleventh and twelfth , their geographical distribution throughout space ; in the thirteenth , their classification or mutual affinities , both when mature and in an embryonic condition . In the ...
Página 7
... organic beings must be exposed during several generations to the new conditions of life to cause any appreciable amount of variation ; and that when the organisation has once begun to vary , it generally continues to vary for many ...
... organic beings must be exposed during several generations to the new conditions of life to cause any appreciable amount of variation ; and that when the organisation has once begun to vary , it generally continues to vary for many ...
Página 39
... organic beings , as some authors have thought . The effects of variability are modified by various degrees of inheritance and of reversion . Variability is governed by many unknown laws , more especially by that of cor- relation of ...
... organic beings , as some authors have thought . The effects of variability are modified by various degrees of inheritance and of reversion . Variability is governed by many unknown laws , more especially by that of cor- relation of ...
Página 41
... organic beings in a state of nature , we must briefly discuss whether these latter are subject to any variation . To treat this subject at all properly , a long catalogue of dry facts should be given ; but these I shall reserve for my ...
... organic beings in a state of nature , we must briefly discuss whether these latter are subject to any variation . To treat this subject at all properly , a long catalogue of dry facts should be given ; but these I shall reserve for my ...
Página 49
... organic beings . But my tables further show that , in any limited country , the species which are most common , that is abound most in individuals , and the species which are most widely diffused within their own country ( and this is a ...
... organic beings . But my tables further show that , in any limited country , the species which are most common , that is abound most in individuals , and the species which are most widely diffused within their own country ( and this is a ...
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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