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XIII
READING THE BOOK OF NATURE

In studying Nature, the important thing is not so much what we see as how we interpret what we see. Do we get at the true meaning of the facts? Do we draw the right inference? The fossils in the rocks were long observed before men drew the right inference from them. So with a hundred other things in nature and life.

During May and a part of June of 1903, a drouth of unusual severity prevailed throughout the land. The pools and marshes nearly all dried up. Late in June the rains came again and filled them up. Then an unusual thing happened: suddenly, for two or three days and nights, the marshes about me were again vocal with the many voices of the hyla, the "peepers" of early spring. That is the fact. Now, what is the interpretation? With me the peepers become silent in early May, and, I suppose, leave the marshes for their life in the woods. Did the drouth destroy all their eggs and young, and did they know this and so come back to try again? How else shall one explain their second appearance in the marshes? But how did they know of the destruction of their young, and how can we account for their concerted action? These are difficulties not easily overcome. A more rational explanation to me is this, namely, that the extreme dryness of the woods – nearly two months without rain – drove the little frogs to seek for moisture in their spring haunts, where in places a little water would be pretty certain to be found. Here they were holding out, probably hibernating again, as such creatures do in the tropics during the dry season, when the rains came, and here again they sent up their spring chorus of voices, and, for aught I know, once more deposited their eggs. This to me is much more like the ways of Nature with her creatures than is the theory of the frogs' voluntary return to the swamps and pools to start the season over again.

The birds at least show little or no wit when a new problem is presented to them. They have no power of initiative. Instinct runs in a groove, and cannot take a step outside of it. One May day we started a meadowlark from her nest. There were three just hatched young in the nest, and one egg lying on the ground about two inches from the nest. I suspected that this egg was infertile and that the bird had had the sense to throw it out, but on examination it was found to contain a nearly grown bird. The inference was, then, that the egg had been accidentally carried out of the nest some time when the sitting bird had taken a sudden flight, and that she did not have the sense to roll or carry it back to its place.

There is another view of the case which no doubt the sentimental "School of Nature Study" would eagerly adopt: A very severe drouth reigned throughout the land; food was probably scarce, and was becoming scarcer; the bird foresaw her inability to care for four young ones, and so reduced the possible number by ejecting one of the eggs from the nest. This sounds pretty and plausible, and so credits the bird with the wisdom that the public is so fond of believing it possesses. Something like this wisdom often occurs among the hive bees in seasons of scarcity; they will destroy the unhatched queens. But birds have no such foresight, and make no such calculations. In cold, backward seasons, I think, birds lay fewer eggs than when the season is early and warm, but that is not a matter of calculation on their part; it is the result of outward conditions.

A great many observers and nature students at the present time are possessed of the notion that the birds and beasts instruct their young, train them and tutor them, much after the human manner. In the familiar sight of a pair of crows foraging with their young about a field in summer, one of our nature writers sees the old birds giving their young a lesson in flying. She says that the most important thing that the elders had to do was to teach the youngsters how to fly. This they did by circling about the pasture, giving a peculiar call while they were followed by their flock – all but one. This was a bobtailed crow, and he did not obey the word of command. His mother took note of his disobedience and proceeded to discipline him. He stood upon a big stone, and she came down upon him and knocked him off his perch. "He squawked and fluttered his wings to keep from falling, but the blow came so suddenly that he had not time to save himself, and he fell flat on the ground. In a minute he clambered back upon his stone, and I watched him closely. The next time the call came to fly he did not linger, but went with the rest, and so long as I could watch him he never disobeyed again." I should interpret this fact of the old and young crows flying about a field in summer quite differently. The young are fully fledged, and are already strong flyers, when this occurs. They do not leave the nest until they can fly well and need no tutoring. What the writer really saw was what any one may see on the farm in June and July: she saw the parent crows foraging with their young in a field The old birds flew about, followed by their brood, clamorous for the food which their parents found. The bobtailed bird, which had probably met with some accident, did not follow, and the mother returned to feed it; the young crow lifted its wings and flapped them, and in its eagerness probably fell off its perch; then when its parent flew away, it followed.

I think it highly probable that the sense or faculty by which animals find their way home over long stretches of country, and which keeps them from ever being lost as man so often is, is a faculty entirely unlike anything man now possesses. The same may be said of the faculty that guides the birds back a thousand miles or more to their old breeding-haunts. In caged or housed animals I fancy this faculty soon becomes blunted. President Roosevelt tells in his "Ranch Life" of a horse he owned that ran away two hundred miles across the plains, swimming rivers on the way to its old home. It is very certain, I think, that this homing feat is not accomplished by the aid of either sight or scent, for usually the returning animal seems to follow a comparatively straight line. It is, or seems to be, a consciousness of direction that is as unerring as the magnetic needle. Reason, calculation, and judgment err, but these primary instincts of the animal seem almost infallible.

In Bronx Park in New York a grebe and a loon lived together in an inclosure in which was a large pool of water. The two birds became much attached to each other and were never long separated. One winter day on which the pool was frozen over, except a small opening in one end of it, the grebe dived under the ice and made its way to the far end of the pool, where it remained swimming about aimlessly for some moments. Presently the loon missed its companion, and with an apparent look of concern dived under the ice and joined it at the closed end of the pool. The grebe seemed to be in distress for want of air. Then the loon settled upon the bottom, and with lifted beak sprang up with much force against the ice, piercing it with its dagger-like bill, but not breaking it. Down to the bottom it went again, and again hurled itself up against the ice, this time shattering it and rising to the surface, where the grebe was quick to follow. Now it looked as if the loon had gone under the ice to rescue its friend from a dangerous situation, for had not the grebe soon found the air, it must have perished, and persons who witnessed the incident interpreted it in this way. It is in such cases that we are so apt to read our human motives and emotions into the acts of the lower animals. I do not suppose the loon realized the danger of its companion, nor went under the ice to rescue it. It followed the grebe because it wanted to be with it, or to share in any food that might be detaining it there, and then, finding no air-hole, it proceeded to make one, as it and its ancestors must often have done before. All our northern divers must be more or less acquainted with ice, and must know how to break it. The grebe itself could doubtless have broken the ice had it desired to. The birds and the beasts often show much intelligence, or what looks like intelligence, but, as Hamerton says, "the moment we think of them as human, we are lost."

A farmer had a yearling that sucked the cows. To prevent this, he put on the yearling a muzzle set full of sharpened nails. These of course pricked the cows, and they would not stand to be drained of their milk. The next day the farmer saw the yearling rubbing the nails against a rock in order, as he thought, to dull them so they would not prick the cows! How much easier to believe that the beast was simply trying to get rid of the awkward incumbrance upon its nose. What can a calf or a cow know about sharpened nails, and the use of a rock to dull them? This is a kind of outside knowledge – outside of their needs and experiences – that they could not possess.

An Arizona friend of mine lately told me this interesting incident about the gophers that infested his cabin when he was a miner. The gophers ate up his bread. He could not hide it from them or put it beyond their reach. Finally, he bethought him to stick his loaf on the end of a long iron poker that he had, and then stand up the poker in the middle of his floor. Still, when he came back to his cabin, he would find his loaf eaten full of holes. One day, having nothing to do, he concluded to watch and see how the gophers reached the bread, and this was what he saw: The animals climbed up the side of his log cabin, ran along one of the logs to a point opposite the bread, and then sprang out sidewise toward the loaf, which each one struck, but upon which only one seemed able to effect a lodgment. Then this one would cling to the loaf and act as a stop to his fellows when they tried a second time, his body affording them the barrier they required. My friend felt sure that this leader deliberately and consciously aided the others in securing a footing on the loaf. But I read the incident differently. This successful jumper aided his fellows without designing it. The exigencies of the situation compelled him to the course he pursued. Having effected a lodgment upon the impaled loaf, he would of course cling to it when the others jumped so as not to be dislodged, thereby, willy nilly, helping them to secure a foothold. The coöperation was inevitable, and not the result of design.

The power to see straight is the rarest of gifts; to see no more and no less than is actually before you; to be able to detach yourself and see the thing as it actually is, uncolored or unmodified by your own sentiments or prepossessions. In short, to see with your reason as well as with your perceptions, that is to be an observer and to read the book of nature aright.

XIV
GATHERED BY THE WAY

I. THE TRAINING OF WILD ANIMALS

I was reminded afresh of how prone we all are to regard the actions of the lower animals in the light of our own psychology on reading "The Training of Wild Animals," by Bostock, a well-known animal-trainer. Bostock evidently knows well the art of training animals, but of the science of it he seems to know very little. That is, while he is a successful trainer, his notions of animal psychology are very crude. For instance, on one page he speaks of the lion as if it were endowed with a fair measure of human intelligence, and had notions, feelings, and thoughts like our own; on the next page, when he gets down to real business, he lays bare its utter want of these things. He says a lion born and bred in captivity is more difficult to train than one caught from the jungle. Then he gives rein to his fancy. "Such a lion does not fear man; he knows his own power. He regards man as an inferior, with an attitude of disdain and silent hauteur." "He accepts his food as tribute, and his care as homage due." "He is aristocratic in his independence." "Deep in him – so deep that he barely realizes its existence – slumbers a desire for freedom and an unutterable longing for the blue sky and the free air." When his training is begun, "he meets it with a reserved majesty and silent indifference, as though he had a dumb realization of his wrongs." All this is a very human way of looking at the matter, and is typical of the way we all – most of us – speak of the lower animals, defining them to ourselves in terms of our own mentality, but it leads to false notions about them. We look upon an animal fretting and struggling in its cage as longing for freedom, picturing to itself the joy of the open air and the free hills and sky, when the truth of the matter undoubtedly is that the fluttering bird or restless fox or lion simply feels discomfort in confinement. Its sufferings are physical, and not mental. Its instincts lead it to struggle for freedom. It reacts strongly against the barriers that hold it, and tries in every way to overcome them. Freedom, as an idea, or a conception of a condition of life, is, of course, beyond its capacity.

Bostock shows how the animal learns entirely by association, and not at all by the exercise of thought or reason, and yet a moment later says: "The animal is becoming amenable to the mastery of man, and in doing so his own reason is being developed," which is much like saying that when a man is practicing on the flying trapeze his wings are being developed. The lion learns slowly through association – through repeated sense impressions. First a long stick is put into his cage. If this is destroyed, it is replaced by another, until he gets used to it and tolerates its presence. Then he is gently rubbed with it at the hands of his keeper. He gets used to this and comes to like it. Then the stick is baited with a piece of meat, and in taking the meat the animal gets still better acquainted with the stick, and so ceases to fear it. When this stage is reached, the stick is shortened day by day, "until finally it is not much longer than the hand." The next step is to let the hand take the place of the stick in the stroking process. "This is a great step taken, for one of the most difficult things is to get any wild animal to allow himself to be touched with the human hand." After a time a collar with a chain attached is slipped around the lion's neck when he is asleep. He is now chained to one end of the cage. Then a chair is introduced into the cage; whereupon this king of beasts, whose reason is being developed, and who has such clear notions of inferior and superior, and who knows his own powers, usually springs for the chair, seeking to demolish it. His tether prevents his reaching it, and so in time he tolerates the chair. Then the trainer, after some preliminary feints, walks into the cage and seats himself in the chair. And so, inch by inch, as it were, the trainer gets control of the animal and subdues him to his purposes, not by appealing to his mind, for he has none, but by impressions upon his senses.

"Leopards, panthers, and jaguars are all trained in much the same manner," and in putting them through their tricks one invariable order must be observed: "Each thing done one day must be done the next day in exactly the same way; there must be no deviation from the rule." Now we do not see in this fact the way of a thinking or reflecting being, but rather the way of a creature governed by instinct or unthinking intelligence. An animal never learns a trick in the sense that man learns it, never sees through it or comprehends it, has no image of it in its mind, and no idea of the relations of the parts of it to one another; it does it by reason of repetition, as a creek wears its channel, and probably has no more self-knowledge or self-thought than the creek has. This, I think, is quite contrary to the popular notion of animal life and mentality, but it is the conclusion that I, at least, cannot avoid after making a study of the subject.

II. AN ASTONISHED PORCUPINE

One summer, while three young people and I were spending an afternoon upon a mountain-top, our dogs treed a porcupine. At my suggestion the young man climbed the tree – not a large one – to shake the animal down. I wished to see what the dogs would do with him, and what the "quill-pig" would do with the dogs. As the climber advanced the rodent went higher, till the limb he clung to was no larger than one's wrist. This the young man seized and shook vigorously. I expected to see the slow, stupid porcupine drop, but he did not. He only tightened his hold. The climber tightened his hold, too, and shook the harder. Still the bundle of quills did not come down, and no amount of shaking could bring it down. Then I handed a long pole up to the climber, and he tried to punch the animal down. This attack in the rear was evidently a surprise; it produced an impression different from that of the shaking. The porcupine struck the pole with his tail, put up the shield of quills upon his back, and assumed his best attitude of defense. Still the pole persisted in its persecution, regardless of the quills; evidently the animal was astonished: he had never had an experience like this before; he had now met a foe that despised his terrible quills. Then he began to back rapidly down the tree in the face of his enemy. The young man's sweetheart stood below, a highly interested spectator. "Look out, Sam, he's coming down!" "Be quick, he's gaining on you!" "Hurry, Sam!" Sam came as fast as he could, but he had to look out for his footing, and his antagonist did not. Still, he reached the ground first, and his sweetheart breathed more easily. It looked as if the porcupine reasoned thus: "My quills are useless against a foe so far away; I must come to close quarters with him." But, of course, the stupid creature had no such mental process, and formed no such purpose. He had found the tree unsafe, and his instinct now was to get to the ground as quickly as possible and take refuge among the rocks. As he came down I hit him a slight blow over the nose with a rotten stick, hoping only to confuse him a little, but much to my surprise and mortification he dropped to the ground and rolled down the hill dead, having succumbed to a blow that a woodchuck or a coon would hardly have regarded at all. Thus does the easy, passive mode of defense of the porcupine not only dull his wits, but it makes frail and brittle the thread of his life. He has had no struggles or battles to harden and toughen him.

That blunt nose of his is as tender as a baby's, and he is snuffed out by a blow that would hardly bewilder for a moment any other forest animal, unless it be the skunk, another sluggish non-combatant of our woodlands. Immunity from foes, from effort, from struggle is always purchased with a price.

Certain of our natural history romancers have taken liberties with the porcupine in one respect: they have shown him made up into a ball and rolling down a hill. One writer makes him do this in a sportive mood; he rolls down a long hill in the woods, and at the bottom he is a ragged mass of leaves which his quills have impaled – : an apparition that nearly frightened a rabbit out of its wits. Let any one who knows the porcupine try to fancy it performing a feat like this!

Another romancer makes his porcupine roll himself into a ball when attacked by a panther, and then on a nudge from his enemy roll down a snowy incline into the water. I believe the little European hedgehog can roll itself up into something like a ball, but our porcupine does not. I have tried all sorts of tricks with him, and made all sorts of assaults upon him, at different times, and I have never yet seen him assume the globular form. It would not be the best form for him to assume, because it would partly expose his vulnerable under side. The one thing the porcupine seems bent upon doing at all times is to keep right side up with care. His attitude of defense is crouching close to the ground, head drawn in and pressed down, the circular shield of large quills upon his back opened and extended as far as possible, and the tail stretched back rigid and held close upon the ground. "Now come on," he says, "if you want to." The tail is his weapon of active defense; with it he strikes upward like lightning, and drives the quills into whatever they touch. In his chapter called "In Panoply of Spears," Mr. Roberts paints the porcupine without taking any liberties with the creature's known habits. He portrays one characteristic of the porcupine very felicitously: "As the porcupine made his resolute way through the woods, the manner of his going differed from that of all the other kindreds of the wild. He went not furtively. He had no particular objection to making a noise. He did not consider it necessary to stop every little while, stiffen himself to a monument of immobility, cast wary glances about the gloom, and sniff the air for the taint of enemies. He did not care who knew of his coming, and he did not greatly care who came. Behind his panoply of biting spears he felt himself secure, and in that security he moved as if he held in fee the whole green, shadowy, perilous woodland world."

III. BIRDS AND STRINGS

A college professor writes me as follows: —

"Watching this morning a robin attempting to carry off a string, one end of which was caught in a tree, I was much impressed by his utter lack of sense. He could not realize that the string was fast, or that it must be loosened before it could be carried off, and in his efforts to get it all in his bill he wound it about a neighboring limb. If as little sense were displayed in using other material for nests, there would be no robins' nests. It impressed me more than ever with the important part played by instinct."

Who ever saw any of our common birds display any sense or judgment in the handling of strings? Strings are comparatively a new thing with birds; they are not a natural product, and as a matter of course birds blunder in handling them. The oriole uses them the most successfully, often attaching her pensile nest to the branch by their aid. But she uses them in a blind, childish way, winding them round and round the branch, often getting them looped over a twig or hopelessly tangled, and now and then hanging herself with them, as is the case with other birds. I have seen a sparrow, a cedar-bird, and a robin each hung by a string it was using in the building of its nest. Last spring, in Spokane, a boy brought me a desiccated robin, whose feet were held together by a long thread hopelessly snarled. The boy had found it hanging to a tree.

I have seen in a bird magazine a photograph of an oriole's nest that had a string carried around a branch apparently a foot or more away, and then brought back and the end woven into the nest. It was given as a sample of a well-guyed nest, the discoverer no doubt looking upon it as proof of an oriole's forethought in providing against winds and storms. I have seen an oriole's nest with a string carried around a leaf, and another with a long looped string hanging free. All such cases simply show that the bird was not master of her material; she bungled; the trailing string caught over the leaf or branch, and she drew both ends in and fastened them regardless of what had happened. The incident only shows how blindly instinct works.

Twice I have seen cedar-birds, in their quest for nesting-material, trying to carry away the strings that orioles had attached to branches. According to our sentimental "School of Nature Study," the birds should have untied and unsnarled the strings in a human way, but they did not; they simply tugged at them, bringing their weight to bear, and tried to fly away with the loose end.

In view of the ignorance of birds with regard to strings, how can we credit the story told by one of our popular nature writers of a pair of orioles that deliberately impaled a piece of cloth upon a thorn in order that it might be held firmly while they pulled out the threads? When it came loose, they refastened it. The story is incredible for two reasons: (1) the male oriole does not assist the female in building the nest; he only furnishes the music; (2) the whole proceeding implies an amount of reflection and skill in dealing with a new problem that none of our birds possess. What experience has the race of orioles had with cloth, that any member of it should know how to unravel it in that way? The whole idea is absurd.

IV. MIMICRY

To what lengths the protective resemblance theory is pushed by some of its expounders! Thus, in the neighborhood of Rio Janeiro there are two species of hawks that closely resemble each other, but one eats only insects and the other eats birds. Mr. Wallace thinks that the bird-eater mimics the insect-eater, so as to deceive the birds, which are not afraid of the latter. But if the two hawks look alike, would not the birds come to regard them both as bird-eaters, since one of them does eat birds? Would they not at once identify the harmless one with their real enemy and thus fear them both alike? If the latter were newcomers and vastly in the minority, then the ruse might work for a while. But if there were ten harmless hawks around to one dangerous one, the former would quickly suffer from the character of the latter in the estimation of the birds. Birds are instinctively afraid of all hawk kind.

Wallace thinks it may be an advantage to cuckoos, a rather feeble class of birds, to resemble the hawks, but this seems to me far-fetched. True it is, if the sheep could imitate the wolf, its enemies might keep clear of it. Why, then, has not this resemblance been brought about? Our cuckoo is a feeble and defenseless bird also, but it bears no resemblance to the hawk. The same can be said of scores of other birds.

Many of these close resemblances among different species of animals are no doubt purely accidental, or the result of the same law of variation acting under similar conditions. We have a hummingbird moth that so closely in its form and flight and manner resembles a hummingbird, that if this resemblance brought it any immunity from danger it would be set down as a clear case of mimicry. There is such a moth in England, too, where no hummingbird is found. Why should not Nature repeat herself in this way? This moth feeds upon the nectar of flowers like the hummingbird, and why should it not have the hummingbird's form and manner?

Then there are accidental resemblances in nature, such as the often-seen resemblance of knots of trees and of vegetables to the human form, and of a certain fungus to a part of man's anatomy. We have a fly that resembles a honey-bee. In my bee-hunting days I used to call it the "mock honey-bee." It would come up the wind on the scent of my bee box and hum about it precisely like a real bee. Of course it was here before the honey-bee, and has been evolved quite independently of it. It feeds upon the pollen and nectar of flowers like the true bee, and is, therefore, of similar form and color. The honey-bee has its enemies; the toads and tree-frogs feed upon it, and the kingbird captures the slow drone.

When an edible butterfly mimics an inedible or noxious one, as is frequently the case in the tropics, the mimicker is no doubt the gainer.

It makes a big difference whether the mimicker is seeking to escape from an enemy, or seeking to deceive its prey. I fail to see how, in the latter case, any disguise of form or color could be brought about.

Our shrike, at times, murders little birds and eats out their brains, and it has not the form, or the color, or the eye of a bird of prey, and thus probably deceives its victims, but there is no reason to believe that this guise is the result of any sort of mimicry.

V. THE COLORS OF FRUITS

Mr. Wallace even looks upon the nuts as protectively colored, because they are not to be eaten. But without the agency of the birds and the squirrels, how are the heavy nuts, such as the chestnut, beechnut, acorn, butternut, and the like, to be scattered? The blue jay is often busy hours at a time in the fall, planting chestnuts and acorns, and red squirrels carry butternuts and walnuts far from the parent trees, and place them in forked limbs and holes for future use. Of course, many of these fall to the ground and take root. If the protective coloration of the nuts, then, were effective, it would defeat a purpose which every tree and shrub and plant has at heart, namely, the scattering of its seed. I notice that the button-balls on the sycamores are protectively colored also, and certainly they do not crave concealment. It is true that they hang on the naked trees till spring, when no concealment is possible. It is also true that the jays and the crows carry away the chestnuts from the open burrs on the trees where no color scheme would conceal them. But the squirrels find them upon the ground even beneath the snow, being guided, no doubt, by the sense of smell.

The hickory nut is almost white; why does it not seek concealment also? It is just as helpless as the others, and is just as sweet-meated. It occurs to me that birds can do nothing with it on account of its thick shell; it needs, therefore, to attract some four-footed creature that will carry it away from the parent tree, and this is done by the mice and the squirrels. But if this is the reason of its whiteness, there is the dusky butternut and the black walnut, both more or less concealed by their color, and yet having the same need of some creature to scatter them.

The seeds of the maple, and of the ash and the linden, are obscurely colored, and they are winged; hence they do not need the aid of any creature in their dissemination. To say that this is the reason of their dull, unattractive tints would be an explanation on a par with much that one hears about the significance of animal and vegetable coloration. Why is corn so bright colored, and wheat and barley so dull, and rice so white? No doubt there is a reason in each case, but I doubt if that reason has any relation to the surrounding animal life.