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able adaptation admit American animals appeared Asa Gray beauty become bees beetle believe birds bone brought California causes characters closely colour common complete conceal conclusion creature descended destroyed developed discovered distinct doubt early earth effect enemy Europe evidence evolution exactly existence experiment fact female flowers follows forms genus give groups habits horse important individuals inherited insects instincts Italy kind known later laws leaf leaves less living look males manner marked means mind modification namely natural selection naturalists never observation once organic Origin past period plants powers present principle probably produced Professor protective reason relation remains resemble rest result scale seems seen similar slight soon South species structure success teeth tend theory tints tion trees United variation varieties whole wild wings wonderful
Página 33 - As all the living forms of life are the lineal descendants of those which lived long before the Cambrian epoch, we may feel certain that the ordinary succession by generation has never once been broken, and that no cataclysm has desolated the whole world. Hence we may look with some confidence to a secure future of great length. And as natural selection works solely by and for the good of each being, all corporeal and mental endowments will tend to progress towards perfection.
Página 33 - It is interesting to contemplate an entangled bank, clothed with many plants of many kinds, with birds singing on the bushes, with various insects flitting about, and with worms crawling through the damp earth, and to reflect that these elaborately constructed forms, so different from each other, and dependent upon each other in so complex a manner, have all been produced by laws acting around us.
Página 37 - I happened to read for amusement ' Malthus on Population ' ; and being well prepared to appreciate the struggle for existence which everywhere goes on from longcontinued observation of the habits of animals and plants, it at once struck me that under these circumstances favorable variations would tend to be preserved, and unfavorable ones to be destroyed. The result of this would be the formation of new species. Here then I had at last got a theory by which to work...
Página 34 - There is grandeur in this view of life, with its several powers, having been originally breathed by the Creator into a few forms or into one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being evolved.
Página 29 - We possess no pedigree or armorial bearings; and we have to discover and trace the many diverging lines of descent in our natural genealogies, by characters of any kind which have long been inherited. Rudimentary organs will speak infallibly with respect to the nature of long-lost structures. Species and groups of species which are called aberrant, and which may fancifully be called living fossils, will aid us in forming a picture of the ancient forms of life. Embryology will often reveal to us the...
Página 36 - It was evident that such facts as these, as well as many others, could only be explained on the supposition that species gradually become modified ; and the subject haunted me. But it was equally evident that neither the action of the surrounding conditions, nor the will of the organisms (especially in the case of plants) could account for the innumerable cases in which organisms of every kind are beautifully adapted to their habits of life — for instance, a woodpecker or a tree-frog to climb trees,...
Página 41 - I had, also, during many years followed a golden rule, namely, that whenever a published fact, a new observation or thought came across me, which was opposed to my general results, to make a memorandum of it without fail and at once; for I had found by experience that such facts and thoughts were far more apt to escape from the memory than favorable ones. Owing to this habit, very few objections were raised against my views which I had not at least noticed and attempted to answer.
Página 38 - The solution, as I believe, is that the modified offspring of all dominant and increasing forms tend to become adapted to many and highly diversified places in the economy of nature.
Página 46 - ... man is descended from some less highly organized form. The grounds upon which this conclusion rests will never be shaken, for the 45 close similarity between man and the lower animals in embryonic development, as well as in innumerable points of structure and constitution, both of high and of the most trifling importance — the rudiments which he retains, and the abnormal reversions to which he is occasionally liable — are facts which cannot be disputed.