The The 1859 1860 1861 1866 1869 |
These facts are explained by the above 1872 |
two principles above given, namely that variations do not generally supervene at a very early age, and that they are inherited at a corresponding age whatever that may have been, seem to me to two principles above given, namely that variations do not generally supervene at a very early age, and that they are inherited at a corresponding age whatever that may have been, seem to me to 1866 |
two principles above given seem to me to 1859 1860 1861 |
above two principles 1869 |
two principles. 1872 |
explain explain 1859 1860 1861 1866 1869 | explain 1872 |
these these 1859 1860 1861 1866 1869 | these 1872 |
several facts regarding the later developmental stages of our domestic varieties. several facts regarding the later developmental stages of our domestic varieties. 1866 |
OMIT 1872 |
facts in regard to the later embryonic stages of our domestic varieties. Fanciers select their horses, dogs, and pigeons, for breeding, when they are nearly grown up: they are indifferent whether the desired qualities and structures have been acquired earlier or later in life, if the full-grown animal possesses them. 1859 1860 1861 |
facts. Fanciers select for breeding their dogs, horses, pigeons, &c., when nearly grown up: they are indifferent whether the desired qualities are acquired earlier or later in life, if the full-grown animal possesses them. 1869 |
Fanciers select their horses, dogs, and pigeons, for breeding, when they are nearly grown up: they are indifferent whether the desired qualities and structures have been Fanciers select their horses, dogs, and pigeons, for breeding, when they are nearly grown up: they are indifferent whether the desired qualities and structures have been 1866 |
And the cases just given, more especially that of pigeons, seem to show that the characteristic differences which give value to each breed, and which have been 1859 1860 1861 |
And the cases just given, more especially that of pigeons, show that the characteristic differences which give value to the breeds and which have been 1869 |
Fanciers select their dogs, horses, pigeons, &c., for breeding, when nearly grown up: they are indifferent whether the desired qualities are 1872 |
acquired earlier or later in life, if the full-grown animal possesses them. acquired earlier or later in life, if the full-grown animal possesses them. 1866 1872 |
accumulated by man's selection, have not generally first appeared at an early period of life, and have been inherited by the offspring at a corresponding not early period. 1859 1861 |
accumulated by mans selection, have not generally first appeared at an early period of life, and have been inherited by the offspring at a corresponding not early period. 1860 |
accumulated by mans selection, have not generally appeared at a very early period of life, and have been inherited at a corresponding not early period. 1869 |
And And 1866 1872 | But 1859 1860 1861 1869 |
the
cases cases 1866 1872 | case 1859 1860 1861 1869 |
just given, more especially that of pigeons, seem to show that just given, more especially that of pigeons, seem to show that 1866 |
of the short-faced tumbler, which when twelve hours old had acquired its proper proportions, proves that this is not the universal rule; for here 1859 1860 1861 |
of the short-faced tumbler, which when twelve hours old possessed its proper characters, proves that this is not the universal rule; for here 1869 |
just given, more especially that of the pigeons, show that 1872 |
the characteristic differences
which give value to each breed, and which which give value to each breed, and which 1866 |
must either have appeared at an earlier period than usual, or, if not so, the differences must 1859 1860 1861 1869 |
which 1872 |
have been
accumulated by man's selection, have not generally first appeared accumulated by man's selection, have not generally first appeared 1866 |
inherited, not at the corresponding, but 1859 1860 1861 |
inherited, not at a corresponding, but 1869 |
accumulated by man's selection, and which give value to his breeds, do not generally appear 1872 |
at
an an 1859 1860 1861 1866 1869 | a very 1872 |
early period of life, and have been inherited by the offspring at a corresponding not early period. early period of life, and have been inherited by the offspring at a corresponding not early period. 1866 |
earlier age. 1859 1860 1861 1869 |
early period of life, and are inherited at a corresponding not early period. 1872 |
But the case of the short-faced tumbler, which when twelve hours old
had acquired had acquired 1866 | possessed 1872 |
its proper
proportions, proportions, 1866 | characters, 1872 |
proves that this is not the universal rule; for here the characteristic differences must either have appeared at an earlier period than usual, or, if not so, the differences must have been inherited, not at
the
corresponding, but at an earlier age. |
Now let us apply these
facts and the above two principles facts and the above two principles 1866 |
facts and the above two principles— which latter, though not proved true, can be shown to be in some degree probable— 1859 1860 1861 |
two principles 1869 1872 |
to species in a state of nature. Let us take a
genus genus 1859 1860 1861 1866 | group 1869 1872 |
of birds, descended
on my theory on my theory 1859 1860 1861 1866 |
OMIT 1869 1872 |
from some
one parent-species, and of which the several new species have become one parent-species, and of which the several new species have become 1859 1860 1861 1866 |
ancient form and 1869 1872 |
modified through natural selection
in accordance with their diverse in accordance with their diverse 1859 1860 1861 1866 |
for different 1869 1872 |
habits. Then, from the many slight successive
steps of steps of 1859 1860 1861 1866 | steps of 1869 1872 |
variation variation 1859 1860 1861 1866 | variations 1869 1872 |
having supervened
at a rather late at a rather late 1859 1860 1861 1866 |
in the several species at a not early 1869 1872 |
age, and having been inherited at a corresponding age, the young
of the new species of our supposed genus will manifestly tend to of the new species of our supposed genus will manifestly tend to 1859 1860 1861 1866 |
will be left but little modified and will 1869 |
will have been but little modified, and they will still 1872 |
resemble each other much more closely than do the
adults, adults, 1859 1860 1861 1866 | adults,— 1869 1872 |
just as we have seen
in in 1859 1860 1861 1866 | with 1869 1872 |
the
case case 1859 1860 1861 1866 | breeds 1869 1872 |
of
pigeons. pigeons. 1859 1860 1861 1866 | the pigeon. 1869 1872 |
We may extend this view to
whole families or even whole families or even 1859 1860 1861 1866 |
widely distinct structures and to whole 1869 1872 |
classes. The fore-limbs, for instance,
|