Comparison with 1869 |
|
methodically, or he may do it unconsciously by preserving the individuals most useful to him at the time,
without any thought
of altering the breed. It is certain that he can largely influence the character of a breed by selecting, in each successive generation, individual differences so slight as to be quite
inappreciable by an
uneducated
eye. This
process process 1859 1860 1861 1866 1869 | unconscious process 1872 |
of selection has been the great agency in the production
of the most distinct and useful domestic breeds. That many of the
breeds produced by man have to a large extent the character of natural species, is shown by the inextricable doubts whether very
many of them are varieties or aboriginal
species.
|
|
There is no
obvious obvious 1859 1860 1861 1866 1869 | obvious 1872 |
reason why the principles which have acted so efficiently under domestication should not
act act 1869 | have acted 1859 1860 1861 1866 1872 |
under nature. In the preservation
of favoured individuals and races, during the constantly-recurrent Struggle for Existence, we see the most
powerful and ever-acting means
of selection. The struggle for existence inevitably follows from the high geometrical ratio of increase which is common to all organic beings. This high rate of increase is proved by calculation,
by the effects of
a succession of peculiar seasons,
and when naturalised in a new country. and when naturalised in a new country. 1869 |
and by the results of naturalisation, as explained in the third chapter. 1859 |
or when naturalised in a new country. 1860 1861 1866 |
and when naturalised in new countries. 1872 |
More individuals are born than can possibly survive. A grain in the balance will
determine which individual
shall live and which shall die,— which variety or species shall increase in number, and which shall decrease, or finally become extinct. As the indi- viduals
of the same species come in all respects into the closest competition with each other, the struggle will generally be most severe between them; it will be almost equally severe between the varieties of the same species, and next in severity between the species of the same genus. But
the struggle
will often be
very very 1859 1860 1861 1866 1869 | very 1872 |
severe between beings
most
remote in the scale of nature. The slightest advantage in one being,
at any age or during any season, over those with which it
comes
into competition, or better adaptation in however slight a degree to the surrounding physical conditions,
will will 1859 1860 1861 1866 1869 | will, 1872 |
turn turn 1859 1860 1861 1866 1869 | in 1872 |
the
balance. balance. 1859 1860 1861 1866 1869 |
long run, turn the balance. 1872 |
|
|
With animals having separated
sexes sexes 1859 1860 1861 1866 1869 | sexes, 1872 |
there will in most cases be
a struggle between the males for possession
of the females. The most vigorous individuals,
or those which have most successfully struggled with their conditions of life, will generally leave most progeny. But success will often depend on having
special weapons
or means of defence, or on the charms of the males; and the slightest
advantage will lead to victory. |
|
As geology plainly proclaims that each land has undergone great
|
methodically, or he may do it unconsciously by preserving the individuals most useful
or pleasing to him or pleasing to him 1869 1872 |
to him at the time, 1859 1860 |
to him at the time 1861 |
to him 1866 |
without any
intention intention 1869 1872 | thought 1859 1860 1861 1866 |
of altering the breed. It is certain that he can largely influence the character of a breed by selecting, in each successive generation, individual differences so slight as to be
....... 1861 1866 1869 1872 | quite 1859 1860 |
inappreciable
except except 1869 1872 | by an 1859 1860 1861 1866 |
by an educated by an educated 1869 1872 |
uneducated 1859 1860 1861 1866 |
eye. This
unconscious process unconscious process 1872 | process 1859 1860 1861 1866 1869 |
of selection has been the great agency in the
formation formation 1869 1872 | production 1859 1860 1861 1866 |
of the most distinct and useful domestic breeds. That many
....... 1869 1872 | of the 1859 1860 1861 1866 |
breeds produced by man have to a large extent the character of natural species, is shown by the inextricable doubts whether
....... 1869 1872 | very 1859 1860 1861 1866 |
many of them are varieties or
aboriginally aboriginally 1861 1866 1869 1872 | aboriginal 1859 1860 |
distinct species. distinct species. 1861 1866 1869 1872 | species. 1859 1860 |
|
|
There is no
....... 1872 | obvious 1859 1860 1861 1866 1869 |
reason why the principles which have acted so efficiently under domestication should not
have acted have acted 1859 1860 1861 1866 1872 | act 1869 |
under nature. In the
survival survival 1869 1872 | preservation 1859 1860 1861 1866 |
of favoured individuals and races, during the constantly-recurrent Struggle for Existence, we see
a a 1869 1872 | the most 1859 1860 1861 1866 |
powerful and ever-acting
form form 1869 1872 | means 1859 1860 1861 1866 |
of
Selection. Selection. 1869 1872 | selection. 1859 1860 1861 1866 |
The struggle for existence inevitably follows from the high geometrical ratio of increase which is common to all organic beings. This high rate of increase is proved by
calculation,— calculation,— 1860 1861 1866 1869 1872 | calculation, 1859 |
by the
rapid increase of many animals and plants during rapid increase of many animals and plants during 1860 1861 1866 1869 1872 |
effects of 1859 |
a succession of peculiar seasons,
and when naturalised in new countries. and when naturalised in new countries. 1872 |
and by the results of naturalisation, as explained in the third chapter. 1859 |
or when naturalised in a new country. 1860 1861 1866 |
and when naturalised in a new country. 1869 |
More individuals are born than can possibly survive. A grain in the balance
may may 1869 1872 | will 1859 1860 1861 1866 |
determine which
individuals individuals 1869 1872 | individual 1859 1860 1861 1866 |
shall live and which shall die,— which variety or species shall increase in number, and which shall decrease, or finally become extinct. As the
individuals individuals 1860 1861 1866 1869 1872 | indi- viduals 1859 |
of the same species come in all respects into the closest competition with each other, the struggle will generally be most severe between them; it will be almost equally severe between the varieties of the same species, and next in severity between the species of the same genus.
On On 1869 1872 | But 1859 1860 1861 1866 |
the
other hand the struggle other hand the struggle 1869 1872 |
struggle 1859 1860 1861 1866 |
will often be
....... 1872 | very 1859 1860 1861 1866 1869 |
severe between
beings beings 1859 1860 1861 1869 1872 | being 1866 |
....... 1869 1872 | most 1859 1860 1861 1866 |
remote in the scale of nature. The slightest advantage in
certain individuals, certain individuals, 1869 1872 | one being, 1859 1860 1861 1866 |
at any age or during any season, over those with which
they they 1869 1872 | it 1859 1860 1861 1866 |
come come 1869 1872 | comes 1859 1860 1861 1866 |
into competition, or better adaptation in however slight a degree to the surrounding physical conditions,
will, will, 1872 | will 1859 1860 1861 1866 1869 |
in in 1872 | turn 1859 1860 1861 1866 1869 |
the
long run, turn the balance. long run, turn the balance. 1872 |
balance. 1859 1860 1861 1866 1869 |
|
|
With animals having separated
sexes, sexes, 1872 | sexes 1859 1860 1861 1866 1869 |
there will
be in most cases be in most cases 1869 1872 |
in most cases be 1859 1860 1861 1866 |
a struggle between the males for
the possession the possession 1866 1869 1872 | possession 1859 1860 1861 |
of the females. The most vigorous
males, males, 1866 1869 1872 | individuals, 1859 1860 1861 |
or those which have most successfully struggled with their conditions of life, will generally leave most progeny. But success will often depend on
the males having the males having 1866 1869 1872 |
having 1859 1860 1861 |
special
weapons, weapons, 1869 1872 | weapons 1859 1860 1861 1866 |
or means of defence, or
charms; and a slight charms; and a slight 1869 1872 |
on the charms of the males; and the slightest 1859 1860 1861 |
on their charms; and the slighest 1866 |
advantage will lead to victory. |
|
As geology plainly proclaims that each land has undergone great
|