다른 사람들의 의견 - 서평 쓰기
서평을 찾을 수 없습니다.
기타 출판본 - 모두 보기
abeut abeve adapted admit affinities allied species America analogous ancient appear beak become bedy bees believe belonging beth birds breeds cause cells characters climate closely allied colour continent crossed crustaceans degree developed difficulty distinct species doubt eggs embryo existing extinct extremely fact favourable fertilised fertility flowers formations forms fossil genera genus geological geological period Glacial period gradations greater number groups of species habits havo Hence hybrids important increase individuals inhabitants inherited insects instance instincts intercrossing intermediate larvae less living male mammals manner Marsupials migration modified descendants natural selection naturalists nearly nest occasionally oceanic islands offspring organisation organs parent peculiar perfect pigeon pistil pollen present principle probably produced quadrupeds ranked reciprocal crosses remarked resemblance rudimentary samo seeds sexual selection Silurian slight South America stamens sterility structure supposed theory tion variable variations varieties vary whilst wings young
50 페이지 - I should premise that I use this term in a large and metaphorical sense, including dependence of one being on another, and including (which is more important) not only the life of the individual, but success in leaving progeny.
63 페이지 - It has been said that I speak of natural selection as an active power or Deity; but who objects to an author speaking of the attraction of gravity as ruling the movements of the planets ? Every one knows what is meant and is implied by such metaphorical expressions; and they are almost necessary for brevity.
65 페이지 - Can we wonder, then, that Nature's productions should be far " truer " in character than man's productions ; that they should be infinitely better adapted to the most complex conditions of life, and should plainly bear the stamp of far higher workmanship...
143 페이지 - To suppose that the eye, with all its inimitable contrivances for adjusting the focus to different distances, for admitting different amounts of light, and for the correction of spherical and chromatic aberration, could have been formed by natural selection, seems, I freely confess, absurd in the highest possible degree.
3 페이지 - As many more individuals of each species are born than can possibly survive ; and as, consequently, there is a frequently recurring struggle for existence, it follows that any being, if it vary however slightly in any manner profitable to itself, under the complex and sometimes varying conditions of life, will have a better chance of surviving, and thus be naturally selected.
56 페이지 - ... there was a large and extremely barren heath, which had never been touched by the hand of man ; but several hundred acres of exactly the same nature had been enclosed twenty-five years previously and planted with Scotch fir. The change in the native vegetation of the planted part of the heath was most remarkable, more than is generally seen in passing from one quite different soil to another ; not only the proportional numbers of the heath-plants were wholly changed, but twelve species of plants...
49 페이지 - Nothing is easier than to admit in words the truth of the universal struggle for life, or more difficult — at least I have found it so — than constantly to bear this conclusion in mind. Yet unless it be thoroughly engrained in the mind, the whole economy of nature, with every fact on distribution, rarity, abundance, extinction, and variation, will be dimly seen or quite misunderstood.
48 페이지 - ... we see beautiful adaptations everywhere and in every part of the organic world.
69 페이지 - The result is not death to the unsuccessful competitor but few or no offspring. Sexual selection is, therefore, less rigorous than natural selection. Generally the most vigorous males, those which are best fitted for their places in nature, will leave most progeny. But in many cases victory depends not so much on general vigor as on having special weapons, confined to the male sex. A hornless stag or spurless cock would have a poor chance of leaving numerous offspring.
412 페이지 - What limit can be put to this power, acting during long ages and rigidly scrutinising the whole constitution, structure, and habits of each creature, — favouring the good and rejecting the bad ? I can see no limit to this power, in slowly and beautifully adapting each form to the most complex relations of life.