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 27
... structure with all the domestic breeds . Secondly , although an English carrier or short - faced tumbler differs immensely in cer- tain characters from the rock - pigeon , yet by comparing the several sub - breeds of these varieties ...
... structure with all the domestic breeds . Secondly , although an English carrier or short - faced tumbler differs immensely in cer- tain characters from the rock - pigeon , yet by comparing the several sub - breeds of these varieties ...
Page 38
... structure , would often succeed better in the one country than in the other ; and thus by a process of " natural selection , " as will hereafter be more fully explained , two sub - breeds might be formed . This , perhaps , partly ...
... structure , would often succeed better in the one country than in the other ; and thus by a process of " natural selection , " as will hereafter be more fully explained , two sub - breeds might be formed . This , perhaps , partly ...
Page 44
... structure in one part , either injurious to or not useful to the species , and not generally propagated . Some authors use the term " variation " in a technical sense , as implying a modifica- tion directly due to the physical ...
... structure in one part , either injurious to or not useful to the species , and not generally propagated . Some authors use the term " variation " in a technical sense , as implying a modifica- tion directly due to the physical ...
Page 45
... structure , which he could collect on good authority , as I have collected , during a course of years . It should be remembered that systematists are far from pleased at finding variability in important characters , and that there are ...
... structure , which he could collect on good authority , as I have collected , during a course of years . It should be remembered that systematists are far from pleased at finding variability in important characters , and that there are ...
Page 52
... structure in certain definite directions . Hence I believe a well - marked variety may be called an incipient species ; but whether this belief be justifiable must be judged of by the general weight of the several facts and views given ...
... structure in certain definite directions . Hence I believe a well - marked variety may be called an incipient species ; but whether this belief be justifiable must be judged of by the general weight of the several facts and views given ...
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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