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able according actual adaptation advance already animals apes appearance become beginning birds body causes character characteristics closely common comparative complete connection course Darwin definite derivation direct division doctrine of Descent effects embryonic entirely evidence example exhibit existence explained external extremely facts families fish follows formation forms further genera Goethe gradually groups higher human idea important individual infer intermediate islands known language latter less likewise limits linguistic living lower mammals manner means merely namely nature observations occur organisms origin perfect period phase phenomena placenta plants portion position possess possible present probable produced progress proved question races recent regard relations remains remarkable represented reproduction reptiles result says seems selection separate sexual sexual reproduction shown shows side similar single species structure systematic theory tion transformation true varieties various vertebrate whole
Página 162 - 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.18 Darwin always knew that his views would be controversial. A few days before The Origin of Species appeared, Darwin wrote, in a letter to Wallace, 'God knows what...
Página 145 - It may metaphorically be said that natural selection is daily and hourly scrutinizing, throughout the world, the slightest variations; rejecting those that are bad, preserving and adding up all that are good; silently and insensibly working, whenever and wherever opportunity offers, at the improvement of each organic being in relation to its organic and inorganic conditions of life.
Página 316 - Tout ce que la nature a fait acquérir ou perdre aux individus par l'influence des circonstances où leur race se trouve depuis longtemps exposée, et par conséquent, par l'influence de l'emploi prédominant de tel organe, ou par celle d'un défaut constant d'usage de telle partie ; elle le conserve par la génération aux nouveaux individus qui en proviennent, pourvu que les changements acquis soient communs aux deux sexes, ou à ceux qui ont produit ces nouveaux individus.
Página 160 - I had not formerly sufficiently considered the existence of many structures which appear to be, as far as we can judge, neither beneficial nor injurious ; and this I believe to be one of the greatest oversights as yet detected in my work.
Página 82 - Was sucht ihr, mächtig und gelind, Ihr Himmelstöne, mich am Staube? Klingt dort umher, wo weiche Menschen sind! Die Botschaft hör ich wohl, allein mir fehlt der Glaube; Das Wunder ist des Glaubens liebstes Kind. Zu jenen Sphären wag...
Página 160 - Na'geli on plants, and the remarks by various authors with respect to animals, more especially those recently made by Professor Broca, that in the earlier editions of my Origin of Species I perhaps attributed too much to the action of natural selection or the survival of the fittest.