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 12
... varieties and sub - varieties differ slightly from each other . The whole organisation seems to have become plastic , and tends to depart in some small degree from that of the parental type . Any variation which is not inherited is ...
... varieties and sub - varieties differ slightly from each other . The whole organisation seems to have become plastic , and tends to depart in some small degree from that of the parental type . Any variation which is not inherited is ...
Page 14
... varieties , when run wild , gradually but certainly revert in character to their aboriginal stocks . Hence it has been argued that no deductions can be drawn from domestic races to species in a state of nature . I have in vain ...
... varieties , when run wild , gradually but certainly revert in character to their aboriginal stocks . Hence it has been argued that no deductions can be drawn from domestic races to species in a state of nature . I have in vain ...
Page 15
... varieties manifested a strong tendency to reversion , that is , to lose their acquired characters , whilst kept under the same conditions , and whilst kept in a considerable body , so that free intercrossing might check , by blending ...
... varieties manifested a strong tendency to reversion , that is , to lose their acquired characters , whilst kept under the same conditions , and whilst kept in a considerable body , so that free intercrossing might check , by blending ...
Page 16
... varieties when crossed , -a subject hereafter to be discussed ) , domestic races of the same species differ from each other in the same manner as , only in most cases in a lesser degree than , do closely- allied species of the same ...
... varieties when crossed , -a subject hereafter to be discussed ) , domestic races of the same species differ from each other in the same manner as , only in most cases in a lesser degree than , do closely- allied species of the same ...
Page 33
... varieties ; and the diversity of fruit of the same species in the orchard , in comparison with the leaves and flowers of the same set of varieties . See how different the leaves of the cabbage are , and how extremely alike the flowers ...
... varieties ; and the diversity of fruit of the same species in the orchard , in comparison with the leaves and flowers of the same set of varieties . See how different the leaves of the cabbage are , and how extremely alike the flowers ...
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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