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 177
... second chapter , presenting on an average a greater number of well - marked varieties than do the rarer species . I may illustrate what I mean by sup- posing three varieties of sheep to be kept , one adapted to an extensive mountainous ...
... second chapter , presenting on an average a greater number of well - marked varieties than do the rarer species . I may illustrate what I mean by sup- posing three varieties of sheep to be kept , one adapted to an extensive mountainous ...
Page 196
... second place , we may sometimes attribute importance to characters which are really of very little importance , and which have originated from quite secondary causes , independently of natural selection . We should remember that climate ...
... second place , we may sometimes attribute importance to characters which are really of very little importance , and which have originated from quite secondary causes , independently of natural selection . We should remember that climate ...
Page 246
... second case they are either not at all developed , or are imperfectly developed . This distinction is important , when the cause of the sterility , which is common to the two cases , has to be considered . The distinction has probably ...
... second case they are either not at all developed , or are imperfectly developed . This distinction is important , when the cause of the sterility , which is common to the two cases , has to be considered . The distinction has probably ...
Page 269
... second place , some emi- nent naturalists believe that a long course of domesti- cation tends to eliminate sterility in the successive generations of hybrids which were at first only slightly sterile ; and if this be so , we surely ...
... second place , some emi- nent naturalists believe that a long course of domesti- cation tends to eliminate sterility in the successive generations of hybrids which were at first only slightly sterile ; and if this be so , we surely ...
Page 347
... second great fact which strikes us in our general review is , that barriers of any kind , or obstacles to free migration , are related in a close and important manner to the differences between the productions of various regions . We ...
... second great fact which strikes us in our general review is , that barriers of any kind , or obstacles to free migration , are related in a close and important manner to the differences between the productions of various regions . We ...
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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