and are beneficial to the being under its conditions of life. No one objects to agriculturists speaking of the potent effects of
selection; and in this case the individual differences given by nature, which man for some object selects, must of necessity first occur. Others have objected that the term selection implies conscious choice in the animals which become modified; and it has even been urged
as plants have no volition, natural selection is not applicable to them! In the literal sense of the word, no doubt, natural selection is a
but who ever objected to chemists speaking of the elective affinities of the various elements? — and yet an acid cannot strictly be said to elect the base with which it
in preference
It has been said that I speak of natural selection as an active power or Deity; but who objects to an author speaking of the attraction of gravity as ruling the movements of the planets? Every one knows what is meant and is implied by such metaphorical expressions; and they are almost necessary for brevity. So again it is difficult to avoid personifying the word Nature; but I mean by Nature, only the aggregate action and product of many natural laws, and by laws the sequence of events as ascertained by us. With a little familiarity such superficial objections will be forgotten. |
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We shall best understand the probable course of natural selection by taking the case of a country undergoing some
change, for instance, of climate. The proportional numbers of its inhabitants
almost immediately undergo a change, and some species
become extinct. We may conclude, from what we have seen of the intimate and complex manner in which the inhabitants of each country are bound together, that any change in the numerical proportions of
the inhabitants, independently of the change
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