Indeed, it may be equally asserted (and the statement is more consonant with some of the facts given), that domestication in certain animals induces and occasions a capacity for change which is wanting in wild animals--the introduction of new causes occasioning new effects.

For, though a certain degree of variability (normally, in all probability, only oscillation) exists in all organisms, yet domestic ones are exposed to new and different causes of variability, resulting in such striking divergencies as have been observed.

Not even in this latter case, however, is it necessary to believe that the variability is indefinite, but only that the small oscillations become in certain instances intensified into large and conspicuous ones.

Moreover, it is possible that some of our domestic animals have been in part chosen and domesticated through possessing variability in an eminent degree.
That each species exhibits certain oscillations of structure is admitted on all hands.

Mr.Darwin asserts that this is the exhibition of a tendency to vary which is absolutely indefinite.