It is evident what great profit accrues from this arrangement whereby a general instinct like imitation takes the place of a number of special instincts, or supplements them.

It gives a measure of plasticity to the creature.

He can now respond suitably to changes in the environment in which he lives.

The special instincts, on the contrary, are for the most part so fixed that the animal must act just as they require him to in this or that circumstance; but as soon as his instinct takes on the form of imitation, the resulting action tends to conform itself to the model actions of the other creatures which set "copies" before him.
These more or less new results due to recent research in the province of Instinct have had direct bearing upon theories of the origin of instinct and of its place in animal life.
_Theories of Instinct._--Apart from the older view which saw in animal instinct simply a matter of original created endowment, whereby each animal was made once for all "after his kind," and according to which there is no further reason that the instincts are what they are than that they were made so; apart from this "special creation" view, two different ideas have had currency, both based upon the theory of evolution.

Each of these views assumes that the instincts have been developed from more simple animal actions by a gradual process; but they differ as to the elements originally entering into the actions which afterward became instinctive.
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