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
... amount of hereditary modification is at least possible ; and , what is equally or more important , we shall see how great is the power of man in accumulating by his Selection successive slight variations . I will then pass on to the ...
... amount of hereditary modification is at least possible ; and , what is equally or more important , we shall see how great is the power of man in accumulating by his Selection successive slight variations . I will then pass on to the ...
Página 7
... 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 generations . No case is on record of VARIATION UNDER DOMESTICATION 7.
... 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 generations . No case is on record of VARIATION UNDER DOMESTICATION 7.
Página 10
... amount of change may , I think , be attributed to the direct action of the conditions of life - as , in some cases , increased size from amount of food , colour from par- ticular kinds of food or from light , and perhaps the thickness ...
... amount of change may , I think , be attributed to the direct action of the conditions of life - as , in some cases , increased size from amount of food , colour from par- ticular kinds of food or from light , and perhaps the thickness ...
Página 15
... amount of struc- tural difference between the domestic races of the same species , we are soon involved in doubt , from not knowing whether they have descended from one or several parent species . This point , if it could be cleared up ...
... amount of struc- tural difference between the domestic races of the same species , we are soon involved in doubt , from not knowing whether they have descended from one or several parent species . This point , if it could be cleared up ...
Página 16
... amount of difference between the several breeds of the dog has been produced under domestica- tion ; I believe that some small part of the difference is due to their being descended from distinct species . In the case of some other ...
... amount of difference between the several breeds of the dog has been produced under domestica- tion ; I believe that some small part of the difference is due to their being descended from distinct species . In the case of some other ...
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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