I cannot see that these actions, performed without experience by the young, and in nearly the same manner by each individual, performed with eager delight by each breed, and without the end being known,--for the young pointer can no more know that he points to aid his master, than the white butterfly knows why she lays her eggs on the leaf of the cabbage,--I cannot see that these actions differ essentially from true instincts.
These domestic instincts, when thus tested by crossing, resemble natural instincts, which in a like manner become curiously blended together, and for a long period exhibit traces of the instincts of either parent: for example, Le Roy describes a dog, whose great-grandfather was a wolf, and this dog showed a trace of its wild parentage only in one way, by not coming in a straight line to his master when called.
Domestic instincts are sometimes spoken of as actions which have become inherited solely from long-continued and compulsory habit, but this, I think, is not true.
Natural instincts are lost under domestication: a remarkable instance of this is seen in those breeds of fowls which very rarely or never become broody,' that is, never wish to sit on their eggs.
Hence, we may conclude, that domestic instincts have been acquired and natural instincts have been lost partly by habit, and partly by man selecting and accumulating during successive generations, peculiar mental habits and actions, which at first appeared from what we must in our ignorance call an accident.
We shall, perhaps, best understand how instincts in a state of nature have become modified by selection, by considering a few cases.
In spite of these qualifications, the broad distinction between instinct and habit is undeniable.
What is true of animals, as regards instinct and habit, is equally true of men.
The popular conception of instinct errs by imagining it to be infallible and preternaturally wise, as well as incapable of modification.
Drever's book there are some interesting examples of the mistakes made by instinct.
207-9) gives a good illustration of an instinct growing wiser through experience.