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a-half Ammonites ancient animal appear Auchentibber basalt beak beds Belemnites belong bones boulder-clay Brachiopoda Broadstone Campsie Carboniferous cave caverns chalk Chonetes clay cliffs coast collection colour containing convex Cretaceous deposits described Devonian district dorsal valve drift East Kilbride Ell coal exist fathoms fishes fissure flint formation fossils fragments Gault genus Geological Society geologists gravel Greensand Hill hinge-line inches interior Island Koninck Lake Lanarkshire Lesmahago Lign lime limestone Lingula locality lower margin miles mineral muscles Museum neighbourhood nodules observed occlusor occur Old Red Sandstone Oolite Phillips pipes plate portion present probably Productus Prof quarry quartz remains remarkable river rocks Saint Acheul sand Scottish seen shale shape shell shore side Silurian slate Sowerby species specimens spines Stirlingshire stone Stonesfield strata surface teeth Tertiary thickness Thornliebank three hundred trachytic tumulus upper veins ventral valve volcanic West Broadstone width
Página 458 - If such do occur, can we doubt (remembering that many more individuals are born than can possibly survive) that individuals having any advantage, however slight, over others, would have the best chance of surviving and of procreating their kind ? On the other hand, we may feel sure that any variation in the least degree injurious would be rigidly destroyed. This preservation of favourable individual differences and variations, and the destruction of those which are injurious, I have called Natural...
Página 458 - It may metaphorically be said that natural selection is daily and hourly scrutinising, 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 147 - God made the earth and the heavens, and every plant of the field before it was in the earth, and every herb of the field before it grew ; for the Lord God had not caused it to rain upon the earth-, and there was not a man to till the ground. But there went up a mist from the earth, and watered the whole face of- the ground.
Página 458 - As man can produce, and certainly has produced, a great result by his methodical and unconscious means of selection, what may not nature effect?
Página 458 - Slow though the process of selection may be, if feeble man can do much by artificial selection, I can see no limit to the amount of change, to the beauty and complexity of the coadaptations between all organic beings, one with another and with their physical conditions of life, which may have been effected in the long course of time through nature's power of selection...
Página 458 - ... the case of an island, or of a country partly surrounded by barriers, into which new and better adapted forms could not freely enter, we should then have places in the economy of nature which would assuredly be better filled up, if some of the original inhabitants were in some manner modified; for, had the area been open to immigration, these same places would have been seized on by intruders. In such...
Página 458 - ... compared with those accumulated by Nature during whole geological periods! 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...
Página 147 - And the Lord God planted a garden eastward, in Eden; and there he put the man whom he had formed. And out of the ground made the Lord God to grow every tree that is pleasant to the sight, and good for food; the tree of life also in the midst of the garden, and the tree of the knowledge of good and evil.
Página 458 - When we reflect on this struggle, we may console ourselves with the full belief, that the war of nature is not incessant, that no fear is felt, that death is generally prompt, and that the vigorous, the healthy, and the happy Btmrive and multiply.
Página 458 - We shall best understand the probable course of natural selection by taking the case of a country undergoing some slight physical change, for instance, of climate. The proportional numbers of its inhabitants will almost immediately undergo a change, and some species will probably become extinct.