It certainly is a most fortunate circumstance that all animals are born with a natural instinct for doing the particular things which they will have to do to make a living in the world. It would certainly be most inconvenient if moles and rats had an instinct to fly, and birds wanted to hide in drains and cellars; if cows thought they must dive into the water to catch fish, and seals tried to come ashore and graze in the pastures. As it is, each creature has the particular set of instincts which make it want to do the things which it can do best.

You remember what I told you in first pages of this book about the little chick inside the egg. It lies quietly and grows, until it is twenty-one days old. On the twenty-first day of its fife, for the first time, the chick feels the instinct to peck. It has no idea why it wants to peck, nor what will happen if it does. He only knows that pecking against the inside of his shell is precisely the one thing that he wants to do. So he pecks away—until, presto! out he comes into a new and very much larger world.

By and by, after the chick has got rested and dried off, he staggers up on his legs, and begins to look around him. His eye catches some small object—peck! he goes again, and catches the bit in his mouth the first time he tries, unerringly. It took you weeks to learn to put your hand where you wanted it; in fact you couldn’t so much as put your fingers in your mouth till you had tried many times. But the chick is born with the pecking instinct, and hits at the very first shot.

Yet the chick does not know what to peck at. He simply lets drive at whatever chances to catch his eye—a bit of gravel it may be, or something very nasty, or even a fleck of light on a blade of grass. What is good to eat and worth pecking at, he has to learn by trying just at you do. Neither does he know anything about drinking. In the course of time, as he goes about pecking at all sorts of things, he snaps at a dew drop on the grass or a sparkle of sun light on the water in his drinking vessel. So he gets his first drink; and in the course of time, he learns what water looks like.

Some day, perhaps, the chick will happen to walk into the water, not seeing any reason why one should not walk on water just as well as on land. Then he will think how very wet and unpleasant water is, and out he will scramble as fast as possible. But if the chick were a duck, tho he would not know anything more about water when he saw it than a chick does, yet as soon as he felt the water on his legs, that feeling would start up his swimming instinct, and away he would go, swimming the first time he tried as well as ever he will. Yet a duckling would sit on the edge of a pond till he grew up to be an old duck before ever the sight of the water would make him want to swim in it. The instinct starts up only when the duck gets its legs wet. Either a duckling or a chick would sit down beside a dish of water till they died of thirst, before they would try to drink, if they did not make a start by pecking at something in the water or on the bottom.

So you see the instinct does not tell the animal anything, it merely starts him to doing something, from which he can learn more for himself. It is just the same with us. We have an instinct to creep, and after that to walk; these take us about so that we can see things for ourselves. We have an instinct to climb; but we have to learn for ourselves how much a branch will bear, and the difference between poplar tree wood which will snap off and spill us out on our heads, and apple tree wood which will not.

So you see that what animals know by instinct is always how to do something. It may be how to swim, or how to fly, or how to build a nest, or how to bite some other creature in the neck. Usually it is some very simple act, that will simply give the creature a start in life.

Did you ever see a kitten play with a mouse? The kitten’s instinct is to chase any small object which is moving away from it—spool, string, tail, ball, mouse, indifferently. The kitten sees the mouse and runs after it. But the kitten will not hurt the mouse as long as the mouse keeps still. You could put the mouse on the kitten’s head and let it go to sleep there, and the kitten would never touch it, so long as the mouse did not try to run away. But the minute the mouse runs, away goes the kitten after it.

We say it is cruel of the kitten to torment the mouse as it does; to let the poor frightened mouse think it has a chance to get away, and when it tries to run, swooping down on it again. But the kitten isn’t cruel. The kitten chases the mouse because it runs; plays with it a few moments; then forgets all about it till it starts to run again. But of course, the kitten is so large and rough compared with a mouse, that sooner or later it is pretty certain to scratch the little creature. Then for the first time, the kitten discovers that there is meat inside the mouse, and that what it thought only an amusing plaything is also good to eat. After that, the kitten becomes a mouser.

It is something the same way with a dog. His instinct is to pursue and bite large things that run away. If, therefore, you run from a dog, he will run after you; and having started running, he is pretty likely to bite. But if you pay no attention to the dog, move only slowly, and do nothing to start up his run-after-something-large-and-bite-it-in-the-legs instinct, the dog will bark, but will not touch you.

One might go on at considerable length describing one after another of the curious instincts of the various creatures we know. Many of these, however, you can see for yourselves, just by watching young animals, kittens, puppies, chicks, babies and the rest, and noticing what they do all of their own accord, without ever being taught.

Of all these curious instincts, I know of nothing more curious than the way in which the instincts of our common nesting birds play hide and seek with one another thru the changing seasons of the year. Each in turn comes to the fore, governs the birds’ conduct for a few weeks, then dies down to give place to the next; but only to reappear once more in its proper place during the following year.

When our song birds come north in the spring, one of the first things they do is to pick out mates, and get to work building their nests. We may be very sure that no young bird, hatched out the year before and building her nest for the first time, has the remotest idea why she is building it. She finds a spot in thicket, hollow tree, or barn, which somehow looks right to her. Then she finds that bits of string, hair, moss, wood, and the like, which she has never bothered her head about before, suddenly become the most interesting and attractive things in the world, and before she knows it, she is building a nest; the same sort of nest that other birds of her sort are building, tho it may be that she was brought up as a pet in the house and has never seen a nest in her life before. When she is older, and has built a great many nests, she will perhaps build the least little bit better than she did the first time; but it will take a pretty sharp eye to tell the difference. The bird who has never seen a nest will always build the right size and kind at the first trial, and build it almost as well as she ever will.

By and by there are eggs in the nest. I don’t suppose the bird knows how they got there, and I am quite sure she doesn’t spend any time wondering about it. The thing she cares for now is to sit on those eggs; and the bits of string, hair, moss, and wood which once seemed so valuable interest her no more.

Still she has not the least idea what the eggs are for. She merely feels that her one desire is to settle down on top of them and sit there; just as you, my reader, at night when you are tired and sleepy, just plain want to lie down on something soft. A little later, and instead of wanting to sit quietly on her nest, the mother bird is possessed to rush round the country, picking up things to eat and stuffing them into hungry little mouths. She can not possibly know what it is all for. She just has a sort of hunger for feeding her babies, as at other times she has a hunger for feeding herself. But a few weeks later, she hasn’t the slightest interest in these children of hers, doesn’t know them by sight, and is just as likely to fight them away if they trouble her as if they were total strangers. The hurry-round-and-find-something-to-feed-the-babies instinct has served its purpose and gone back into cold storage. Another instinct is taking its place, and pretty soon the birds will be off for the south to spend the winter. Next year they will do the same thing right over again. But how much they remember of what happened the year before is just one of those things that I, among others, would give something to find out.