| → OMIT 1866 1869 1872 |
| where I say that 1861 |
|
| → we make due allowance 1869 1872 |
| due allowance be made 1861 1866 |
|
| → past epochs in its history. 1869 |
| many past epochs in its history. 1861 1866 |
| present time, and still more so during past ages. 1872 |
|
| → clearer; but it would be useless to discuss all of them, as many have been made by writers who have not taken the trouble to understand my views. 1869 |
| clearer. 1861 |
| clearer; but it would be useless to discuss all of them, as they have been made by writers who have not taken the trouble to understand my views. 1866 |
|
| → OMIT 1869 |
| under which they live, 1866 |
|
| → in many quarters of the world yielding their places 1869 |
| yielding their places in many quarters of the world 1866 |
|
| → foreigners which have become naturalised. 1869 |
| and naturalised foreigners. 1866 |
|
| → they were at 1869 |
| at 1866 |
|
| → unless they likewise change; and 1869 |
| and 1866 |
|
| ↑ 4 blocks not present in 1859 1860 1861 1869 1872; present in 1866 |
| Thus again, a French author, in opposition to the whole tenor of this volume, assumes that, according to my view, species undergo great and abrupt changes, and then he triumphantly asks how this is possible, seeing that such modified forms would be crossed by the many which have remained unchanged.
No doubt the small changes or variations which do occur are incessantly checked and retarded by intercrossing; but the frequent existence of varieties in the same country with the parent species shows that crossing does not necessarily prevent their formation; and in the still more frequent cases of local forms or geographical races, crossing cannot come into play.
It should also be borne in mind that the offspring from a cross between a modified and unmodified species tends partially to inherit the characters of both parents, and natural selection assuredly will preserve even slight approaches to any change of structure which is beneficial.
Moreover such crossed offspring, from partaking of the same constitution with the modified parent, and from being still exposed to the same conditions, will be far more liable than other individuals of the same species again to vary or be modified in a similar manner.
|
|
|
towards the close of the Introduction,
→OMIT
no one ought to feel surprise at much remaining as yet unexplained on the origin of species, if
→we make due allowance
for our profound ignorance on the mutual relations of the inhabitants of the world
the
→past epochs in its history.
|
|
|
| I will here notice a few miscellaneous objections which have been advanced against my views, as some of the previous discussions may perhaps thus be made
→clearer; but it would be useless to discuss all of them, as many have been made by writers who have not taken the trouble to understand my views. Thus a distinguished German naturalist has recently asserted that the weakest part of my theory is, that I consider all organic beings as imperfect: what I have really said is, that all are not as perfect in relation to
conditions
→OMIT
as they might be; and this is shown to be the case by so many native forms
→in many quarters of the world yielding their places
to intruding
→foreigners which have become naturalised. Nor can all organic beings, even if
→they were at
any one time perfectly adapted to their conditions of life, remain so, when
conditions slowly
→unless they likewise change; and
no one will dispute that the physical conditions of each country, as well as the
and
of its inhabitants, are liable to
↑
It has been argued
as none of the animals and plants of Egypt, of which we know anything, have changed during the last 3000 years, so probably none have been modified in
of the world. The many animals which have remained unchanged since the commencement of the glacial period would have been an incomparably stronger case, for these have been
|
