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 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 ...
Page 7
... 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 a variable being ceasing. CHAP . I. VARIATION UNDER DOMESTICATION . 7.
... 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 a variable being ceasing. CHAP . I. VARIATION UNDER DOMESTICATION . 7.
Page 10
... in the same way , the change at first appears to be directly due to such conditions ; but in some cases it can be shown that quite opposite conditions produce similar changes of structure . Nevertheless some slight amount of. CHAP . I.
... in the same way , the change at first appears to be directly due to such conditions ; but in some cases it can be shown that quite opposite conditions produce similar changes of structure . Nevertheless some slight amount of. CHAP . I.
Page 11
... 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 ...
Page 16
... 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 ...
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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