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The Darwinian Theory of the Transmutation of Species
Robert MacKenzie Beverley
Sin vista previa disponible - 2016
able according acknowledged action admit advance advantage ages animals appear arrangement beauty become beginning believe birds blood body bones called cause certain character common condition considered continually course created creation creatures Darwin difficulty direction distinct earth effected evidence existence explain expressed fact favoured female fishes formation forms geology give habits hand horse human imagination improvement individual instance instinct known learned less light living lower matter means millions modification Natural Selection never object observed organic origin passage perfect period plants present principle produced progenitor progress proof proved question race reason remarks result says seems seen Silurian soil species sterility structure struggle successive suppose term Theory things thousand tion transformation Transmutation true turn varieties vertebrated whole
Página 20 - And God made the beast of the earth after his kind, and cattle after their kind, and every thing that creepeth upon the earth after his kind: and God saw that it was good.
Página 70 - Under changed conditions of life, it is at least possible that slight modifications of instinct might be profitable to a species; and if it can be shown that instincts do vary ever so little, then I can see no difficulty in natural selection preserving and continually accumulating variations of instinct to any extent that was profitable. It is thus, as I believe, that all the most complex and wonderful instincts have originated.
Página 20 - And God said, Let the earth bring forth grass, the herb yielding seed and the fruit tree yielding fruit after his kind, whose seed is in itself, upon the earth: and it was so. And the earth brought forth grass, and herb yielding seed after his kind, and the tree yielding fruit, whose seed was in itself, after his kind: and God saw that it was good.
Página 348 - Slow though the process of selection may be, if feeble man can do much by his powers of artificial selection, I can see no limit. to the amount of change, to the beauty and infinite complexity of the coadaptations between all organic beings, one with another and with their physical conditions of life, which may be effected in the long course of time by nature's power of selection.
Página 7 - In short, we shall have to treat species in the same manner as those naturalists treat genera, who admit that genera are merely artificial combinations made for convenience. This may not be a cheering prospect ; but we shall at least be freed from the vain search for the undiscovered and undiscoverable essence of the term species.
Página 232 - the recognition of an ideal Exemplar for the Vertebrated Animals proves that the Knowledge of such a being as Man must have existed before Man appeared. For the Divine mind which planned the Archetype also foreknew all its modifications. The Archetypal idea was manifested in the flesh, under divers modifications, upon this planet, long prior to the existence of those animal species that actually exemplify it.
Página 61 - The similar framework of bones in the hand of a man, wing of a bat, fin of the porpoise, and leg of the horse, — the same number of vertebrae forming the neck of the giraffe and of the elephant, — and innumerable other such facts, at once explain themselves on the theory of descent with slow and slight successive modifications.
Página 1 - These facts, as will be seen in the latter chapters of this volume, seemed to throw some light on the origin of species — that mystery of mysteries, as it has been called by one of our greatest philosophers.
Página 136 - I may be allowed to personify the natural preservation or survival of the fittest, cares nothing for appearances, except in so far as they are useful to any being. She can act on every internal organ, on every shade of constitutional difference, on the whole machinery of life. Man selects only for his own good : Nature only for that of the being which she tends.
Página 170 - Consequently, if my theory be true, it is indisputable that before the lowest Silurian stratum was deposited, long periods elapsed, as long as, or probably far longer than, the whole interval from the Silurian age to the present day; and that during these vast, yet quite unknown, periods of time, the world swarmed with living creatures.