Again, it may be asked, how is it that varieties, which I have called incipient species, become ultimately converted into good and distinct species, which in most cases obviously differ from each other far more than do the varieties of the same species? How do those groups of species, which constitute what are called distinct genera, and which differ from each other more than do the species of the same genus, arise? All these results, as we shall more fully see in the next chapter, follow
....... 1860 1861 1866 1869 1872 | inevitably 1859 |
from the struggle for life. Owing to this
struggle, struggle, 1869 1872 | struggle 1859 1860 1861 1866 |
...OMIT 1869 1872 |
for life, any 1859 1860 1861 1866 |
variations, variations, 1869 1872 | variation, 1859 1860 1861 1866 |
however
slight, slight, 1860 1861 1866 1869 1872 | slight 1859 |
and from whatever cause proceeding, if
they they 1869 1872 | it 1859 1860 1861 1866 |
be in any degree profitable to
the the 1869 1872 | an 1859 1860 1861 1866 |
individuals individuals 1869 1872 | individual 1859 1860 1861 1866 |
of
a a 1869 1872 | any 1859 1860 1861 1866 |
species, in
their their 1869 1872 | its 1859 1860 1861 1866 |
infinitely complex relations to other organic beings and to
their physical conditions of life, their physical conditions of life, 1869 1872 |
external nature, 1859 1860 |
its physical conditions of life, 1861 1866 |
will tend to the preservation of
such such 1869 1872 | that 1859 1860 1861 1866 |
individuals, individuals, 1869 1872 | individual, 1859 1860 1861 1866 |
and will generally be inherited by
the the 1869 1872 | its 1859 1860 1861 1866 |
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
....... 1861 1866 1869 1872 | of 1859 1860 |
Natural Selection, in order to mark its relation to
mans mans 1869 | man's 1859 1860 1861 1866 1872 |
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
use- ful use- ful 1869 | useful 1859 1860 1861 1866 1872 |
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
mans mans 1869 | man's 1859 1860 1861 1866 1872 |
feeble efforts, as the works of Nature are to those of Art.
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