the next
chapter, follow from the struggle for life. Owing to this struggle,
variations, however slight and from whatever cause proceeding, if they
be in any degree profitable to the individuals of a species, in their
infinitely complex relations to other organic beings and to their
physical conditions of life, will tend to the preservation of such
individuals, and will generally be inherited by the offspring. The
offspring also will thus have a better chance of surviving; for of the
many individuals of any species which are periodically born, but a small
number can survive. I have called this principle, by which each slight
variation, if useful, is preserved, by the term Natural Selection, in
order to mark its relation to man's power of selection. But the
expression often used by Mr. Herbert Spencer, of the Survival of the
Fittest, is more accurate and is sometimes equally convenient. We have
seen that man by selection can certainly produce great results, and can
adapt organic beings to his own uses, through the accumulation of slight
but useful variations given to him by the hand of Nature. But Natural
Selection, as we shall hereafter see, is a power incessantly ready for
action, and is as immeasurably superior to man's feeble efforts as the
works of Nature are to those of Art.
We will now discuss in a little more detail the struggle for existence.
In my future work this subject will be treated, as it well deserves, at
greater length. The elder De Candolle and Lyell have largely and
philosophically shown that all organic beings are exposed to severe
competition. In regard to plants, no one has treated this subject with
more spirit and ability than W. Herbert, Dean of Manchester, evidently
the result of his great horticultural knowledge. Nothing is easier than
to admit in words the truth of the universal struggle for life, or more
difficult--at least I have found it so--than constantly to bear this
conclusion in mind. Yet unless it be thoroughly ingrained in the mind,
the whole economy of nature, with every fact on distribution, rarity,
abundance, extinction, and variation, will be dimly seen or quite
misunderstood. We behold the face of nature bright with gladness, we
often see superabundance of food; we do not see, or we forget, that the
birds which are idly singing round us mostly live on insects or seeds,
and are thus constantly destroying life; or we forget how largely these
songsters, or their eggs, or their ne
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