On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for Life"In considering the Origin of Species, it is quite conceivable that a naturalist, reflecting on the mutual affinities of organic beings, on their embryological relations, their geographical distribution, geological succession, and other such facts, might come to the conclusion that each species had not been independently created, but had descended, like varieties, from other species. Nevertheless, such a conclusion, even if well founded, would be unsatisfactory, until it could be shown how the innumerable species inhabiting this world have been modified, so as to acquire that perfection of structure and coadaptation which most justly excites our admiration. Naturalists continually refer to external conditions, such as climate, food, & c, as the only possible cause of variation. In one very limited sense, as we shall hereafter see, this may be true; but it is preposterous to attribute to mere external conditions, the structure, for instance, of the woodpecker, with its feet, tail, beak, and tongue, so admirably adapted to catch insects under the bark of trees. In the case of the misseltoe, which draws its nourishment from certain trees, which has seeds that must be transported by certain birds, and which has flowers with separate sexes absolutely requiring the agency of certain insects to bring pollen from one flower to the other, it is equally preposterous to account for the structure of this parasite, with its relations to several distinct organic beings, by the effects of external conditions, or of habit, or of the volition of the plant itself"--Introduction. (PsycINFO Database Record (c) 2012 APA, all rights reserved) |
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Page 52
... become extinct , or they may endure as varieties for very long periods , as has been shown to be the case by Mr. Wollaston with the varie- ties of certain fossil land - shells in Madeira . If a variety were to flourish so as to exceed ...
... become extinct , or they may endure as varieties for very long periods , as has been shown to be the case by Mr. Wollaston with the varie- ties of certain fossil land - shells in Madeira . If a variety were to flourish so as to exceed ...
Page 53
... become ex- posed to diverse physical conditions , and as they come into competition ( which , as we shall hereafter see , is a far more important circumstance ) with different sets of organic beings . But my tables further show that ...
... become ex- posed to diverse physical conditions , and as they come into competition ( which , as we shall hereafter see , is a far more important circumstance ) with different sets of organic beings . But my tables further show that ...
Page 54
... become in any degree permanent , necessarily have to struggle with the other inhabitants of the country , the species which are already dominant will be the most likely to yield offspring , which , though in some slight degree modified ...
... become in any degree permanent , necessarily have to struggle with the other inhabitants of the country , the species which are already dominant will be the most likely to yield offspring , which , though in some slight degree modified ...
Page 59
... become converted into new and distinct species . The larger genera thus tend to become larger ; and throughout nature the forms of life which are now dominant tend to become still more dominant by leav- ing many modified and dominant ...
... become converted into new and distinct species . The larger genera thus tend to become larger ; and throughout nature the forms of life which are now dominant tend to become still more dominant by leav- ing many modified and dominant ...
Page 64
... had not been well authenticated , they would have been incre- dible . So it is with plants : cases could be given of introduced plants which have become common through- out whole islands. 64 CHAP . III . HIGH RATE OF INCREASE .
... had not been well authenticated , they would have been incre- dible . So it is with plants : cases could be given of introduced plants which have become common through- out whole islands. 64 CHAP . III . HIGH RATE OF INCREASE .
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Common terms and phrases
adapted affinities allied species America analogous ancient animals become bees believe birds breeds cause cells chapter characters cirripedes climate closely allied colour continuous crossed crustaceans degree difficulty distinct species divergence domestic doubt embryo Europe existing exterminated extinct extremely facts favourable Fcap fertility flowers formations forms fossil Gärtner genera genus geological geological period Glacial period greater number groups of species habits Hence hermaphrodites History hybrids hybrids produced important individuals inhabitants inherited insects instance instincts intercrossing intermediate land larvæ less living male mammals manner migration modification modified descendants natural selection naturalists nearly nest offspring perfect pigeons plants pollen Portrait Post 8vo present principle probably produced progenitor racter ranked reciprocal crosses remarked resemble rudimentary organs Second Edition seeds sexual selection Silurian slight South America sterility structure struggle successive supposed theory Third Edition tion variability variations varieties vary Vols widely Woodcuts