On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for LifeJ. Murray, 1860 - 502페이지 "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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16 페이지
... ranked by competent judges as mere varieties , and by other competent judges as the descendants of aboriginally distinct species . If any marked distinction existed between domestic races and species , this source of doubt could not so ...
... ranked by competent judges as mere varieties , and by other competent judges as the descendants of aboriginally distinct species . If any marked distinction existed between domestic races and species , this source of doubt could not so ...
22 페이지
... wild birds , would certainly , I think , be ranked by him as well - defined species . Moreover , I do not believe that any ornithologist would place the English carrier , the short - faced tumbler , the. 22 CHAP . I. DOMESTIC PIGEONS .
... wild birds , would certainly , I think , be ranked by him as well - defined species . Moreover , I do not believe that any ornithologist would place the English carrier , the short - faced tumbler , the. 22 CHAP . I. DOMESTIC PIGEONS .
36 페이지
... preservation of the best indi- viduals , whether or not sufficiently distinct to be ranked at their first appearance as distinct varieties , and whether or not two or more species or races have become. 36 CHAP . I. UNCONSCIOUS SELECTION .
... preservation of the best indi- viduals , whether or not sufficiently distinct to be ranked at their first appearance as distinct varieties , and whether or not two or more species or races have become. 36 CHAP . I. UNCONSCIOUS SELECTION .
47 페이지
... ranked as a variety of another , not because the intermediate links have actually been found , but because analogy leads the observer to suppose either that they do now somewhere exist , or may formerly have existed ; and here a wide ...
... ranked as a variety of another , not because the intermediate links have actually been found , but because analogy leads the observer to suppose either that they do now somewhere exist , or may formerly have existed ; and here a wide ...
48 페이지
... ranked by one botanist as good species , and by another as mere varieties . Mr. H. C. Watson , to whom I lie under ... ranked by botanists as species ; and in making this list he has omitted many trifling varieties , but which never ...
... ranked by one botanist as good species , and by another as mere varieties . Mr. H. C. Watson , to whom I lie under ... ranked by botanists as species ; and in making this list he has omitted many trifling varieties , but which never ...
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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