On the Origin of Species by Means of Natural Selection: Or, The Preservation of Favoured Races in the Struggle for LifeJ. Murray, 1860 - 502 páginas "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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Página vi
... genus - The relation of organism to organism the most important of all relations CHAPTER IV . NATURAL SELECTION . — Page 60-79 Natural Selection - its power compared with man's selection - its power on characters of trifling importance ...
... genus - The relation of organism to organism the most important of all relations CHAPTER IV . NATURAL SELECTION . — Page 60-79 Natural Selection - its power compared with man's selection - its power on characters of trifling importance ...
Página 16
... genus , in several trifling respects , they often differ in an extreme degree in some one part , both when compared one with another , and more especially when compared with all the species in nature to which they are nearest allied ...
... genus , in several trifling respects , they often differ in an extreme degree in some one part , both when compared one with another , and more especially when compared with all the species in nature to which they are nearest allied ...
Página 18
... genus , which is distributed in a wild state through- out the world , that since man first appeared one single species alone should have been domesticated . In re- gard to sheep and goats I can form no opinion . I should think , from ...
... genus , which is distributed in a wild state through- out the world , that since man first appeared one single species alone should have been domesticated . In re- gard to sheep and goats I can form no opinion . I should think , from ...
Página 23
... genus ; more especially as in each of these breeds several truly- inherited sub - breeds , or species as he might have called them , could be shown him . Great as the differences are between the breeds of pigeons , I am fully convinced ...
... genus ; more especially as in each of these breeds several truly- inherited sub - breeds , or species as he might have called them , could be shown him . Great as the differences are between the breeds of pigeons , I am fully convinced ...
Página 54
... genus in- habiting any country , shows that there is something in the organic or inorganic conditions of that country favourable to the genus ; and , consequently , we might have expected to have found in the larger genera , or those ...
... genus in- habiting any country , shows that there is something in the organic or inorganic conditions of that country favourable to the genus ; and , consequently , we might have expected to have found in the larger genera , or those ...
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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