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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viii 페이지
... living species - On the state of development of ancient forms On the succession of the same types within the same areas 312-345 Summary of preceding and present chapters CHAPTER XI . GEOGRAPHICAL DISTRIBUTION . - Present distribution ...
... living species - On the state of development of ancient forms On the succession of the same types within the same areas 312-345 Summary of preceding and present chapters CHAPTER XI . GEOGRAPHICAL DISTRIBUTION . - Present distribution ...
8 페이지
... living long under not very close con- finement in their native country ! This is generally attributed to vitiated instincts ; but how many cultivated plants display the utmost vigour , and yet rarely or never seed ! In some few such ...
... living long under not very close con- finement in their native country ! This is generally attributed to vitiated instincts ; but how many cultivated plants display the utmost vigour , and yet rarely or never seed ! In some few such ...
94 페이지
... living and leaving descendants . Its descendants would probably inherit a tendency to a similar slight deviation of structure . The tubes of the corollas of the common red and incarnate clovers ( Trifolium pratense and in- carnatum ) do ...
... living and leaving descendants . Its descendants would probably inherit a tendency to a similar slight deviation of structure . The tubes of the corollas of the common red and incarnate clovers ( Trifolium pratense and in- carnatum ) do ...
107 페이지
... living fossils ; they have endured to the present day , from having inhabited a confined area , and from having thus been exposed to less severe competition . To sum up the circumstances favourable and un- favourable to natural ...
... living fossils ; they have endured to the present day , from having inhabited a confined area , and from having thus been exposed to less severe competition . To sum up the circumstances favourable and un- favourable to natural ...
113 페이지
... living on the same piece of ground . And we well know that each species and each variety of grass is annually sowing almost countless seeds ; and thus , as it may be said , is striving its utmost to increase its numbers . Con- sequently ...
... living on the same piece of ground . And we well know that each species and each variety of grass is annually sowing almost countless seeds ; and thus , as it may be said , is striving its utmost to increase its numbers . Con- sequently ...
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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