Let us suppose that a tiger is trying to creep up to a deer through the jungle, as quietly as he can. The tiger is still a long way off, and quite hidden by the bushes, so the deer cannot _see_ him at all. But the deer can _hear_ him coming, even if the tiger takes each step very lightly. Why? Because the deer's ears are so sharp that he can hear even a leaf rustling under the tiger's foot, a long way off. So the deer can run away in good time. To make him hear still better, the deer can turn or bend his ears to the side from which the sound is coming. You have seen an ordinary cow prick up her ears when she heard somebody coming; and many other animals--even a dog--can do the same. But the deer can do that best. The shape of his ear is like that of a funnel, so as to _pour_ the sound into his ear, as it were. Then even if there is only a single drop of sound, it gets right into his ear. And by turning or bending his ear, the deer knows which way the sound is coming. You also can tell which way a sound is coming, if it is loud enough; but the deer can do that even when the sound is very faint. That is very useful to him, as he then knows exactly _which way_ a sneaking tiger is coming, and can run the _other way_. I must now tell you that the tiger himself, tries to come so quietly that the deer may not hear him at all; and to help him to do so, his feet are padded with muscles, just like cushions. So it is a kind of trial between the tiger and the deer as to which is the more clever. If the tiger can come so quietly that the deer cannot hear him, then the tiger is more clever than the deer. But if the deer can hear the tiger, even if the tiger comes most quietly, then the deer is more clever than the tiger. That kind of trial between two different animals as to which is the more clever, goes on in the jungle all the time: and _the more clever one wins every time_. If the tiger is more clever than the deer, the tiger eats the deer; but if the deer is more clever than the tiger, the deer escapes being eaten. And that is true of all other animals. In fact, one of the great wonders of the jungle is that the animal which is _the fittest wins the oftenest_; and so he goes on living, whatever may happen to the others.[1] [Footnote 1: _To the Teacher._--Please give the class other examples of the "Survival of the Fittest" among other creatures--birds, insects, fish, etc.] Now I come to the second special gift of the deer and the antelope. If by any chance a deer cannot hear a sneaking tiger, he can still _smell_ the tiger. Most animals can smell their enemy a long way off, even if they do not hear him or see him; but _the deer and the antelope can smell the farthest_. Even if a sneaking tiger is so cunning that he stops in a thicket and stands quite still for a minute, so that he does not make any sound at all,--and so the deer cannot hear him,--even then the deer can smell him when he is still a long way off.