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acquired action acts adapted already amongst ancient animals appears aquatic arise beauty become believe birds body bones cause certain changes CHAPTER characters complex considerable Darwin definite depends deposits descendants developed direct early effect enable energy evidence evolution excreted existence explained external extremely facts favour fish forces formation forms give rise given gradually hence higher highly hypothesis ideas important increase individual influence inheritance kind known laws least less light living lower mammals manner material matter maturity means mind modification natural selection nature nourishment nutrition occur offspring organs origin parent perhaps period phenomena plants plasticity Plate present probably produce protoplasm race relation remain remarkable reproduction reptiles result rudimentary seen separated similar skull specialized species strata structure suppose surface tend theory tion tissue transitional undergo undoubtedly variability variation vary vertebrates vibrations whilst wings young
Página 136 - I look at the geological record as a history of the world imperfectly kept, and written in a changing dialect; of this history we possess the last volume alone, relating only to two or three countries. Of this volume, only here and there a short chapter has been preserved ; and of each page, only here and there a few lines.
Página 120 - Whilst at work I seemed to myself to have been endeavouring to decipher a palimpsest, and one not erased and written upon again just once, but five or six times over. " Having erased, as it were, the characters of the culminating type — those of the gaudy Indian bird — I seemed to be amongst the sombre grouse ; and then, towards incubation, the characters of the sand-grouse and hemipod stood out before me. Rubbing these away, in my downward work the form of the tinamou looked me in the face ;...
Página 148 - ... yet it is not improbable that there is a certain amount of interference between the development of free intelligence and of instinct — which latter implies some inherited modification of the brain. Little is known about the functions of the brain, but we can perceive that as the intellectual powers become highly developed, the various parts of the brain must be connected by very intricate channels of the freest intercommunication; and as a consequence, each separate part would perhaps tend...
Página 109 - As natural selection acts solely by the preservation of profitable modifications, each new form will tend in a fully-stocked country to take the place of, and finally to exterminate, its own less improved parent-form and other less-favoured forms with which it comes into competition.
Página 140 - At some future period, not very distant as measured by centuries, the civilized races of man will almost certainly exterminate and replace throughout the world the savage races.
Página 49 - If strange and rare deviations of structure are really inherited, less strange and commoner deviations may be freely admitted to be inheritable. Perhaps the correct way of viewing the whole subject would be, to look at the inheritance of every character whatever as the rule, and non-inheritance as the anomaly.
Página 33 - Several writers have misapprehended or objected to the term Natural Selection. Some have even imagined that natural selection induces variability, whereas it implies only the preservation of such variations as arise and are beneficial to the being under its conditions of life.