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) |
도서 본문에서
97개의 결과 중 1 - 5개
6 페이지
... allied species has a narrow range and is rare ? Yet these relations are of the highest importance , for they determine the present welfare , and , as I believe , the future success and modification of inhabitant every of this world ...
... allied species has a narrow range and is rare ? Yet these relations are of the highest importance , for they determine the present welfare , and , as I believe , the future success and modification of inhabitant every of this world ...
15 페이지
... allied species , we generally perceive in each domestic race , as already remarked , less uniformity of character than in true species . Domestic races of the same species , also , often have a somewhat monstrous character ; by which I ...
... allied species , we generally perceive in each domestic race , as already remarked , less uniformity of character than in true species . Domestic races of the same species , also , often have a somewhat monstrous character ; by which I ...
16 페이지
... allied . With these exceptions ( and with that of the perfect fertility of 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 ...
... allied . With these exceptions ( and with that of the perfect fertility of 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 ...
17 페이지
... allied natural species - for in- stance , of the many foxes - inhabiting different quarters of the world . I do not believe , as we shall presently see , that the whole amount of difference between the several breeds of the dog has been ...
... allied natural species - for in- stance , of the many foxes - inhabiting different quarters of the world . I do not believe , as we shall presently see , that the whole amount of difference between the several breeds of the dog has been ...
21 페이지
... allied to the carrier , but , instead of a very long beak , has a very short and very broad one . The pouter has a much elongated body , wings , and legs ; and its enormously developed crop , which it glories in inflating , may well ...
... allied to the carrier , but , instead of a very long beak , has a very short and very broad one . The pouter has a much elongated body , wings , and legs ; and its enormously developed crop , which it glories in inflating , may well ...
기타 출판본 - 모두 보기
자주 나오는 단어 및 구문
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