It may
perhaps | perhaps 1861 | perhaps 1866 1869 1872 |
| monstrosities, or such 1861 |
| OMIT 1866 1869 1872 |
| great 1861 1866 1869 | | considerable 1872 |
| as 1861 | | such as 1866 1869 1872 |
| Monsters are very apt to be sterile; and 1861 |
| OMIT 1866 1869 1872 |
| almost 1861 | | Almost 1866 1869 1872 |
| being, 1861 | | being 1866 1869 1872 |
| at least with animals, 1861 |
| OMIT 1866 1869 1872 |
| 3 blocks not present in 1859 1860 1861; present in 1866 1869 1872 | | Under domestication monstrosities sometimes
occur which resemble
normal structures
in widely different animals. Thus pigs have occasionally
been born with a sort of proboscis,
and if any wild species
of the same genus
had naturally possessed a proboscis, it might have been argued that this had
appeared
as a monstrosity; but I have as yet failed
to find, after diligent search,
cases of monstrosities resembling
normal structures in nearly allied forms, and these alone bear on the question.
If monstrous forms of this kind ever do appear in a state of nature and are capable of reproduction
(which is not always the case), as they occur rarely and singly, their preservation would depend on unusually favourable circumstances.
|
| 1 blocks not present in 1859 1860 1861 1869 1872; present in 1866 | | If perpetuated in this crossed state, their preservation will be almost necessarily due to the modification being in some way beneficial to the animal under its then existing conditions of life; so that, even in this case, natural selection will come into play.
|
| Subtitle not present 1859 1860 1861 |
|
Individual
Differences. 1866 |
|
