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 v
... Habit - Correlation of Growth-- Inheritance - Character of Domestic Varieties - Difficulty of distinguishing between Varieties and Species - Origin of Domestic Varieties from one or more Species - Domestic Pigeons , their Differences ...
... Habit - Correlation of Growth-- Inheritance - Character of Domestic Varieties - Difficulty of distinguishing between Varieties and Species - Origin of Domestic Varieties from one or more Species - Domestic Pigeons , their Differences ...
Página vii
... habits of life - Diversified habits in the same species - Species with habits widely different from those of their allies - Organs of extreme perfection - Means of transition - Cases of difficulty- Natura non facit saltum - Organs of ...
... habits of life - Diversified habits in the same species - Species with habits widely different from those of their allies - Organs of extreme perfection - Means of transition - Cases of difficulty- Natura non facit saltum - Organs of ...
Página 18
... habits , voice , and constitution , & c . , of the humped Indian cattle , that these had descended from a different aboriginal stock from our European cattle ; and several competent judges believe that these latter have had more than ...
... habits , voice , and constitution , & c . , of the humped Indian cattle , that these had descended from a different aboriginal stock from our European cattle ; and several competent judges believe that these latter have had more than ...
Página 21
... habit of flying at a great height in a compact flock , and tumbling in the air head over heels . The runt is a bird of great size , with long , massive beak and large feet ; some of the sub - breeds of runts have very long necks ...
... habit of flying at a great height in a compact flock , and tumbling in the air head over heels . The runt is a bird of great size , with long , massive beak and large feet ; some of the sub - breeds of runts have very long necks ...
Página 23
... habits , and remarkable characters , seems very improbable ; or they must have become extinct in the wild state . But birds breeding on preci- pices , and good fliers , are unlikely to be exterminated ; and the common rock - pigeon ...
... habits , and remarkable characters , seems very improbable ; or they must have become extinct in the wild state . But birds breeding on preci- pices , and good fliers , are unlikely to be exterminated ; and the common rock - pigeon ...
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Términos y frases comunes
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