Page:George Archdall Reid 1896 The present evolution of man.djvu/169

Rh to stimulation, so as to place themselves in harmony with an environment which has become more complex, and that higher in the scale this power, of which reason is the outcome, increases more and more, till in amphibians and reptiles, the traits acquired by virtue of it sometimes contradict and overpower the dictates of instinct. But even the highest reptiles, with few exceptions, are provided with an equipment of reflexes and instincts sufficient to enable them to enter on the battle of life unaided immediately on emerging from the egg. It is far otherwise with birds and mammals, which, to an increasing extent, as they are higher placed in the scale, depend for survival less and less on instinct, on inborn inherited knowledge and ways of thinking and acting, and more and more on reason, on acquired knowledge and ways of thinking and acting; and therefore to an increasing extent are helpless and unfit for the battle when hatched or born, and for an increasing length of time are protected by, and receive tuition from, one or other of their parents, whereby they acquire such knowledge and ways of thinking and acting as enable th$m to enter on the battle with advantage.

In the lower birds and mammals, in which the cerebrum is least developed, instinct still predominates over reason. A young chick, for instance, emerges from the egg the possessor of a large amount of hereditary knowledge, supplemented later by an amount of acquired