Among nearly all our birds, the female is the active business member of the partnership; she has a turn for practical affairs; she chooses the site of the nest, and usually builds it unaided. The life of the male is more or less a holiday or picnic till the young are hatched, when his real cares begin, for he does his part in feeding them. One may see the male cedar-bird attending the female as she is busy with her nest-building, but never, so far as I have observed, a.s.sisting her. One spring I observed with much interest a phoebe-bird building her nest not far from my cabin in the woods. The male looked on approvingly, but did not help. He perched most of the time on a mullein stalk near the little spring run where Phoebe came for mud.

In the early morning hours she made her trips at intervals of a minute or two. The male flirted his tail and called encouragingly, and when she started up the hill with her load he would accompany her part way, to help her over the steepest part, as it were, then return to his perch and watch and call for her return. For an hour or more I witnessed this little play in bird life, in which the female's part was so primary and the male's so secondary. There is something in such things that seems to lend support to Professor Lester F. Ward's contention, as set forth in his "Pure Sociology," that in the natural evolution of the two s.e.xes the female was first and the male second; that he was made from her rib, so to speak, and not she from his.

With our phalarope and a few Australian birds, the position of the two s.e.xes as indicated above is reversed, the females having the ornaments and bright colors and doing the courting, while the male does the incubating. In a few cases also the female is much the more masculine, noisy, and pugnacious. With some of our common birds, such as the woodp.e.c.k.e.rs, the chickadee, and the swallows, both s.e.xes take part in nest-building.

It is a very pretty sight to witness a pair of wood thrushes building their nest. Indeed, what is there about the wood thrush that is not pleasing? He is a kind of visible embodied melody. Some birds are so sharp and nervous and emphatic in their movements, as the common s...o...b..rd or junco, the flashing of whose white tail quills expresses the character of the bird. But all the ways of the wood thrush are smooth and gentle, and suggest the melody of its song. It is the only bird thief I love to see carrying off my cherries. It usually takes only those dropped upon the ground by other birds, and with the red or golden globe impaled upon its beak, its flight across the lawn is a picture delightful to behold. One season a pair of them built a nest in a near-by grove; morning after morning, for many mornings, I used to see the two going to and from the nest, over my vineyard and currant patch and pear orchard, in quest of, or bringing material for, the structure. They flew low, the female in the lead, the male just behind in line with her, timing his motions to hers, the two making a brown, gently undulating line, very pretty to look upon, from my neighbor's field where they obtained the material, to the tree that held the nest. A gentle, gliding flight, hurried but hushed, as it were, and expressive of privacy and loving preoccupation. The male carried no material; apparently he was simply the escort of his mate; but he had an air of keen and joyous interest. He never failed to attend her each way, keeping about a yard behind her, and flying as if her thought were his thought and her wish his wish. I have rarely seen anything so pretty in bird life. The movements of all our thrushes except the robin give one this same sense of harmony,--nothing sharp or angular or abrupt. Their gestures are as pleasing as their notes.

One evening, while seated upon my porch, I had convincing proof that musical or song contests do take place among the birds. Two wood thrashes who had nests near by sat on the top of a dead tree and pitted themselves against each other in song for over half an hour, contending like champions in a game, and certainly affording the rarest treat in wood thrush melody I had ever had. They sang and sang with unwearied spirit and persistence, now and then changing position or facing in another direction, but keeping within a few feet of each other. The rivalry became so obvious and was so interesting that I finally made it a point not to take my eyes from the singers. The twilight deepened till their forms began to grow dim; then one of the birds could stand the strain no longer, the limit of fair compet.i.tion had been reached, and seeming to say, "I will silence you, anyhow," it made a spiteful dive at its rival, and in hot pursuit the two disappeared in the bushes beneath the tree. Of course I would not say that the birds were consciously striving to outdo each other in song; it was the old feud between males in the love season, not a war of words or of blows, but of song. Had the birds been birds of brilliant plumage, the rivalry would probably have taken the form of strutting and showing off their bright colors and ornaments.

An English writer on birds, Edmund Selous; describes a similar song contest between two nightingales. "Jealousy," he says, "did not seem to blind them to the merit of each other's performance. Though often one, upon hearing the sweet, hostile strains, would burst forth instantly itself,--and here there was no certain mark of appreciation,--yet sometimes, perhaps quite as often, it would put its head on one side and listen with exactly the appearance of a musical connoisseur, weighing, testing, and appraising each note as it issued from the rival bill. A curious, half-suppressed expression would steal, or seem to steal (for Fancy may play her part in such matters), over the listening bird, and the idea appear to be, 'How exquisite would be those strains were they not sung by ----, and yet I must admit that they are exquisite.'" Fancy no doubt does play a part in such matters. It may well be doubted if birds are musical connoisseurs, or have anything like human appreciation of their own or of each other's songs. My reason for thinking so is this: I have heard a bobolink with an instrument so defective that its song was broken and inarticulate in parts, and yet it sang with as much apparent joy and abandon as any of its fellows. I have also heard a hermit thrush with a similar defect or impediment that appeared to sing entirely to its own satisfaction. It would be very interesting to know if these poor singers found mates as readily as their more gifted brothers. If they did, the Darwinian theory of "s.e.xual selection" in such matters, according to which the finer songster would carry off the female, would fall to the ground. Yet it is certain that it is during the mating and breeding season that these "song combats" occur, and the favor of the female would seem to be the matter in dispute. Whether or not it be expressive of actual jealousy or rivalry, we have no other words to apply to it.

A good deal of light is thrown upon the ways of nature as seen in the lives of our solitary wasps, so skillfully and charmingly depicted by George W. Peckham and his wife in their work on those insects. So whimsical, so fickle, so forgetful, so fussy, so wise, and yet so foolish, as these little people are! such victims of routine and yet so individual, such apparent foresight and yet such thoughtlessness, at such great pains and labor to dig a hole and build a cell, and then at times sealing it up without storing it with food or laying the egg, half finishing hole after hole, and then abandoning them without any apparent reason; sometimes killing their spiders, at other times only paralyzing them; one species digging its burrow before it captures its game, others capturing the game and then digging the hole; some of them hanging the spider up in the fork of a weed to keep it away from the ants while they work at their nest, and running to it every few minutes to see that it is safe; others laying the insect on the ground while they dig; one species walking backward and dragging its spider after it, and when the spider is so small that it carries it in its mandible, still walking backward as if dragging it, when it would be much more convenient to walk forward. A curious little people, leading their solitary lives and greatly differentiated by the solitude, hardly any two alike, one nervous and excitable, another calm and unhurried; one careless in her work, another neat and thorough; this one suspicious, that one confiding; Ammophila using a pebble to pack down the earth in her burrow, while another species uses the end of her abdomen,--verily a queer little people, with a lot of wild nature about them, and a lot of human nature, too.

I think one can see how this development of individuality among the solitary wasps comes about. May it not be because the wasps are solitary? They live alone. They have no one to imitate; they are uninfluenced by their fellows. No community interests override or check individual whims or peculiarities. The innate tendency to variation, active in all forms of life, has with them full sway. Among the social bees or wasps one would not expect to find those differences between individuals. The members of a colony all appear alike in habits and in dispositions. Colonies differ, as every bee-keeper knows, but probably the members composing it differ very little. The community interests shape all alike. Is it not the same in a degree among men? Does not solitude bring out a man's peculiarities and differentiate him from others? The more one lives alone, the more he becomes unlike his fellows. Hence the original and racy flavor of woodsmen, pioneers, lone dwellers in Nature's solitudes. Thus isolated communities develop characteristics of their own. Constant intercommunication, the friction of travel, of streets, of books, of newspapers, make us all alike; we are, as it were, all pebbles upon the same sh.o.r.e, washed by the same waves.

Among the larger of vertebrate animals, I think, one might reasonably expect to find more individuality among those that are solitary than among those that are gregarious; more among birds of prey than among water-fowl, more among foxes than among prairie-dogs, more among moose than among sheep or buffalo, more among grouse than among quail.

But I do not know that this is true.

Yet among none of these would one expect to find the diversity of individual types that one finds among men. No two dogs of the same breed will be found to differ as two men of the same family often differ. An original fox, or wolf, or bear, or beaver, or crow, or crab,--that is, one not merely different from his fellows, but obviously superior to them, differing from them as a master mind differs from the ordinary mind,--I think, one need not expect to find.

It is quite legitimate for the animal-story writer to make the most of the individual differences in habits and disposition among the animals; he has the same lat.i.tude any other story writer has, but he is bound also by the same law of probability, the same need of fidelity to nature. If he proceed upon the theory that the wild creatures have as p.r.o.nounced individuality as men have, that there are master minds among them, inventors and discoverers of new ways, born captains and heroes, he will surely "o'erstep the modesty of nature."

The great diversity of character and capacity among men doubtless arises from their greater and more complex needs, relations, and aspirations. The animals' needs in comparison are few, their relations simple, and their aspirations _nil_. One cannot see what could give rise to the individual types and exceptional endowments that are often claimed for them. The law of variation, as I have said, would give rise to differences, but not to a sudden reversal of race habits, or to animal geniuses.

The law of variation is everywhere operative--less so now, no doubt, than in the earlier history of organic life on the globe. Yet Nature is still experimenting in her blind way, and hits upon many curious differences and departures. But I suppose if the race of man were exterminated, man would never arise again. I doubt if the law of evolution could ever again produce him, or any other species of animal.

This principle of variation was no doubt much more active back in geologic time, during the early history of animal life upon the globe, than it is in this late age. And for the reason that animal life was less adapted to its environment than it is now, the struggle for life was sharper. Perfect adaptation of any form of life to the conditions surrounding it seems to check variability. Animal and plant life seem to vary more in this country than in England because the conditions of life are harder. The extremes of heat and cold, of wet and dry, are much greater. It has been found that the eggs of the English sparrow vary in form and color more in the United States than in Great Britain. Certain American sh.e.l.ls are said to be more variable than the English. Among our own birds it has been found that the "migratory species evince a greater amount of individual variation than do non-migrating species" because they are subject to more varying conditions of food and climate. I think we may say, then, if there were no struggle for life, if uniformity of temperature and means of subsistence everywhere prevailed, there would be little or no variation and no new species would arise. The causes of variation seem to be the inequality and imperfection of things; the pressure of life is unequally distributed, and this is one of Nature's ways that accounts for much that we see about us.

VIII

WHAT DO ANIMALS KNOW?

After the discussion carried on in the foregoing chapters touching the general subject of animal life and instinct, we are prepared, I think, to ask with more confidence, What do animals know?

The animals unite such ignorance with such apparent knowledge, such stupidity with such cleverness, that in our estimate of them we are likely to rate their wit either too high or too low. With them, knowledge does not fade into ignorance, as it does in man; the contrast is like that between night and day, with no twilight between.

So keen one moment, so blind the next!

Think of the ignorance of the horse after all his long a.s.sociation with man; of the trifling things along the street at which he will take fright, till he rushes off in a wild panic of fear, endangering his own neck and the neck of his driver. One would think that if he had a particle of sense he would know that an old hat or a bit of paper was harmless. But fear is deeply implanted in his nature; it has saved the lives of his ancestors countless times, and it is still one of his ruling pa.s.sions.

I have known a cow to put her head between two trees in the woods--a kind of natural stanchion--and not have wit enough to get it out again, though she could have done so at once by lifting her head to a horizontal position. But the best instance I know of the grotesque ignorance of a cow is given by Hamerton in his "Chapters on Animals."

The cow would not "give down" her milk unless she had her calf before her. But her calf had died, so the herdsman took the skin of the calf, stuffed it with hay, and stood it up before the inconsolable mother.

Instantly she proceeded to lick it and to yield her milk. One day, in licking it, she ripped open the seams, and out rolled the hay. This the mother at once proceeded to eat, without any look of surprise or alarm. She liked hay herself, her acquaintance with it was of long standing, and what more natural to her than that her calf should turn out to be made of hay! Yet this very cow that did not know her calf from a bale of hay would have defended her young against the attack of a bear or a wolf in the most skillful and heroic manner; and the horse that was nearly frightened out of its skin by a white stone, or by the flutter of a piece of newspaper by the roadside, would find its way back home over a long stretch of country, or find its way to water in the desert, with a certainty you or I could not approach.

The hen-hawk that the farm-boy finds so difficult to approach with his gun will yet alight upon his steel trap fastened to the top of a pole in the fields. The rabbit that can be so easily caught in a snare or in a box-trap will yet conceal its nest and young in the most ingenious manner. Where instinct or inherited knowledge can come into play, the animals are very wise, but new conditions, new problems, bring out their ignorance.

A college girl told me an incident of a red squirrel she had observed at her home in Iowa that ill.u.s.trates how shallow the wit of a squirrel is when confronted by new conditions. This squirrel carried nuts all day and stored them in the end of a drainpipe that discharged the rain-water upon the pavement below. The nuts obeyed the same law that the rain-water did, and all rolled through the pipe and fell upon the sidewalk. In the squirrel's experience, and in that of his forbears, all holes upon the ground were stopped at the far end, or they were like pockets, and if nuts were put in them they stayed there. A hollow tube open at both ends, that would not hold nuts--this was too much for the wit of the squirrel. But how wise he is about the nuts themselves!

Among the lower animals the ignorance of one is the ignorance of all, and the knowledge of one is the knowledge of all, in a sense in which the same is not true among men. Of course some are more stupid than others of the same species, but probably, on the one hand, there are no idiots among them, and, on the other, none is preeminent in wit.

Animals take the first step in knowledge--they perceive things and discriminate between them; but they do not take the second step--combine them, a.n.a.lyze them, and form concepts and judgments.

So that, whether animals know much or little, I think we are safe in saying that what they know in the human way, that is, from a process of reasoning, is very slight.

The animals all have in varying degrees perceptive intelligence. They know what they see, hear, smell, feel, so far as it concerns them to know it. They know their kind, their mates, their enemies, their food, heat from cold, hard from soft, and a thousand other things that it is important that they should know, and they know these things just as we know them, through their perceptive powers.

We may ascribe intelligence to the animals in the same sense in which we ascribe it to a child, as the perception of the differences or of the likenesses and the relations of things--that is, perceptive intelligence, but not reasoning intelligence. When the child begins to "notice things," to know its mother, to fear strangers, to be attracted by certain objects, we say it begins to show intelligence.

Development in this direction goes on for a long time before it can form any proper judgment about things or take the step of reason.

If we were to subtract from the sum of the intelligence of an animal that which it owes to nature or inherited knowledge, the amount left, representing its own power of thought, would be very small. Darwin tells of a pike in an aquarium separated by plate-gla.s.s from fish which were its proper food, and that the pike, in trying to capture the fish, would often dash with such violence against the gla.s.s as to be completely stunned. This the pike did for three months before it learned caution. After the gla.s.s was removed, the pike would not attack those particular fishes, but would devour others that were introduced. It did not yet understand the situation, but merely a.s.sociated the punishment it had received with a particular kind of fish.

During the mating season the males of some of our birds may often be seen dashing themselves against a window, and pecking and fluttering against the pane for hours at a time, day after day. They take their own images reflected in the gla.s.s to be rival birds, and are bent upon demolishing them. They never comprehend the mystery of the gla.s.s, because gla.s.s is not found in nature, and neither they nor their ancestors have had any experience with it.

Contrast these incidents with those which Darwin relates of the American monkeys. When the monkeys had cut themselves once with any sharp tool, they would not touch it again, or else would handle it with the greatest caution. They evinced the simpler forms of reason, of which monkeys are no doubt capable.

Animals are wise as Nature is wise; they partake, each in its own measure, of that universal intelligence, or mind-stuff, that is operative in all things--in the vegetable as well as in the animal world. Does the body, or the life that fills it, reason when it tries to get rid of, or to neutralize the effects of, a foreign substance, like a bullet, by encysting it? or when it thickens the skin on the hand or on any other part of the body, even forming special pads called callosities, as a result of the increased wear or friction?

This may be called physiological intelligence.

But how blind this intelligence is at times, or how wanting in judgment, may be seen when it tries to develop a callosity upon the foot as a result of the friction of the shoe, and overdoes the matter and produces the corn. The corn is a physiological blunder. Or see an unexpected manifestation of this intelligence when we cut off the central and leading shoot of a spruce or of a pine tree, and straightway one of the lateral and horizontal branches rises up, takes the place of the lost leader, and carries the tree upward; or in the roots of a tree working their way through the ground much like molten metal, parting and uniting, taking the form of whatever object they touch, shaping themselves to the rock, flowing into its seams, the better to get a grip upon the earth and thus maintain an upright position.

In the animal world this foresight becomes psychic intelligence, developing in man the highest form of all, reasoned intelligence. When an animal solves a new problem or meets a new condition as effectually as the tree or the body does in the cases I have just cited, we are wont to ascribe to it powers of reason. Reason we may call it, but it is reason not its own.

This universal or cosmic intelligence makes up by far the greater part of what animals know. The domestic animals, such as the dog, that have long been under the tutelage of man, of course show more independent power of thought than the uneducated beasts of the fields and woods.

The plant is wise in all ways to reproduce and perpetuate itself; see the many ingenious devices for scattering seed. In the animal world this intelligence is most keen and active in the same direction. The wit of the animal comes out most clearly in looking out for its food and safety. We are often ready to ascribe reason to it in feats shown in these directions.

In man alone does this universal intelligence or mind-stuff reach out beyond these primary needs and become aware of itself. What the plant or the animal does without thought or rule, man takes thought about.

He considers his ways, I noticed that the scallops in the shallow water on the beach had the power to anchor themselves to stones or to some other object, by putting out a little tough but elastic cable from near the hinge, and that they did so when the water was rough; but I could not look upon It as an act of conscious or individual intelligence on the part of the bivalve. It was as much an act of the general intelligence to which I refer as was its hinge or its form.

But when the sailor anchors his ship, that is another matter. He thinks about it, he reasons from cause to effect, he sees the storm coming, he has a fund of experience, and his act is a special individual act.

The muskrat builds its house instinctively, and all muskrats build alike. Man builds his house from reason and forethought. Savages build as nearly alike as the animals, but civilized man shows an endless variety. The higher the intelligence, the greater the diversity.

The sitting bird that is so solicitous to keep its eggs warm, or to feed and defend its young, probably shows no more independent and individual intelligence than the plant that strives so hard to mature and scatter its seed. A plant will grow toward the light; a tree will try to get from under another tree that overshadows it; a willow will run its roots toward the water: but these acts are the results of external stimuli alone.

When I go to pa.s.s the winter in a warmer climate, the act is the result of calculation and of weighing pros and cons. I can go, of I can refrain from going. Not so with the migrating birds. Nature plans and thinks for them; it is not an individual act on the part of each; it is a race instinct: they must go; the life of the race demands it.

Or when the old goose covers up her nest, or the rabbit covers her young with a blanket of hair and gra.s.s of her own weaving, I do not look upon these things as independent acts of intelligence: it is the cunning of nature; it is a race instinct.

Animals, on the whole, know what is necessary for them to know--what the conditions of life have taught their ancestors through countless generations. It is very important, for instance, that amphibians shall have some sense that shall guide them to the water; and they have such a sense. It is said that young turtles and crocodiles put down anywhere will turn instantly toward the nearest water. It is certain that the beasts of the field have such a sense much more fully developed than has man. It is of vital importance that birds should know how to fly, how to build their nests, how to find their proper food, and when and where to migrate, without instruction or example, otherwise the race might become extinct.

Richard Jefferies says that most birds'-nests need a structure around them like a cage to keep the young from falling out or from leaving the nest prematurely. Now, if such a structure were needed, either the race of birds would have failed, or the structure would have been added. Since neither has happened, we are safe in concluding it is not needed.

We are not warranted in attributing to any wild, untrained animal a degree of intelligence that its forbears could not have possessed. The animals for the most part act upon inherited knowledge, that is, knowledge that does not depend upon instruction or experience. For instance, the red squirrels near me seem to know that chestnut-burs will open if cut from the tree and allowed to lie upon the ground. At least, they act upon this theory. I do not suppose this fact or knowledge lies in the squirrel's mind as it would in that of a man--as a deduction from facts of experience or of observation. The squirrel cuts off the chestnuts because he is hungry for them, and because his ancestors for long generations have cut them off in the same way. That the air or sun will cause the burs to open is a bit of knowledge that I do not suppose he possesses in the sense in which we possess it: he is in a hurry for the nuts, and does not by any means always wait for the burs to open; he frequently chips them up and eats the pale nuts.

The same squirrel will bite into the limbs of a maple tree in spring and suck the sap. What does he know about maple trees and the spring flow of sap? Nothing as a mental concept, as a bit of concrete knowledge. He often finds the sap flowing from a crack or other wound in the limbs of a maple, and he sips it and likes it. Then he sinks his teeth into the limb, as his forbears undoubtedly did.

When I was a boy and saw, as I often did on my way to school, where a squirrel had stopped on his course through the woods and dug down through two or three feet of snow, bringing up a beech-nut or an acorn, I used to wonder how he knew the nut was there. I am now convinced that he smelled it.