In the first place, the bees of the same swarm do not look alike or act alike except superficially; at least I have not so observed them. Study the heads or the feet of any two bees under a glass, and you shall find as much variety as in the heads or feet of any other two creatures of the same kind, whether brute or human. The lines of difference run smaller, to be sure; but they are always there. In action also the bees are variable; they do marvelously wise things at one moment, or marvelously stupid things at another; but they do not all and always do the same thing under the same circumstances, for when I have experimented with selected bees from the same hive I have noticed very different results; which leads me to suspect that even here I am dealing with individuals rather than with detached fragments of a swarm. It is hard, for example, to make a trap so simple that an imprisoned bee will find his way out of it; [[121]]but when by great ingenuity you do at last make a trap so very simple that it seems any creature with legs must walk out by the open door, perhaps one bee in five will do the trick; while the other four wait patiently until they die for more simplicity.
Again, while your eye often sees unity of action among the wild creatures, neither your reading nor your own reason will ever reveal a scrap of positive evidence that there is in nature any such convenient thing (humanly convenient, that is, for explanations) as a swarm or flock instinct; though, like the mythical struggle for existence, we are forever hearing about it or building theories upon it. So far as we know anything about instinct, it is neither collective nor incorporeal. It is, to use the definition of Mark Hopkins, which is as good as another and beautifully memorable, “a propensity prior to experience and independent of instruction.” And the only needful addition to this high-sounding definition is, that it is a “propensity” lodged in an individual, every time. It is not and cannot be lodged in a swarm or a hive; you must either put it into each of two bees or else put it between them, leaving them both untouched. In other words, the swarm instinct has logically no abiding-place and no reality; it is a castle in the air with no solid foundation to rest on. [[122]]
On its practical or pragmatic side also the theory is a failure, since the things bees are said to do in obedience to an incorporeal swarm instinct are more naturally and more reasonably explained by other causes. Bees swarm, apparently, in the lead or under the influence of individuals; and it needs only a pair of eyes to discover that there are plenty of individual laggards and blunderers in the process. They grow angry not all at once, but successively; not because a swarm instinct impels them to anger, but because one irritated bee gives off a pungent odor or raises a militant buzzing, and the others smell the odor or hear the buzzing and are inflamed by it, each through his own senses and by the working of his own motives. On a hot day you will see a few bees fanning air into the hive with their wings, and when these grow weary others take their places; but if it were a swarm instinct that impelled them, you would see all the bees fanning or all sweltering at the same moment. As for the honey-making instinct, on any early-spring day you will find a few bees working in the nearest greenhouse, while the others, which are supposed to be governed by the same collective impulse, are comfortably torpid in the hive or else eating honey faster than these enterprising ones can make it.
I judge, therefore, that the communistic bees [[123]]have some individual notions, and any show of individuality is so at variance with the common-impulse theory that it seems to illustrate Spencer’s definition of tragedy, which is, “a theory slain by a fact.” In short, bees have our common social instinct highly developed, or overdeveloped, and possibly they have also, like all the higher orders, a stronger or weaker instinct of imitation; but these are very different matters, more natural and more consistent with the facts than is the alleged swarm instinct.
A scientific friend, the most observant ornithologist I have ever met, has just offered an interesting explanation of the flock or herd phenomena we are here considering. He finds little evidence of a swarm instinct, as distinct from our familiar social instinct; but he has often marveled at the wing drill of birds, and has twice witnessed an alarm or warning of danger spread silently among a herd of scattered beasts; and he accounts for the observed facts by the supposition that the minds (or what corresponds to the minds) of the lower orders are often moved not from within, but from without—that is, not by instinct or by sense impressions, not by what they or others of their kind may see or hear, but by some external and unknown influence. My caribou rushed away, he thinks, and my incoming plover turned as one [[124]]bird from my decoys, because a warning impulse fell upon them at a moment when they were in danger, but knew it not; and they obeyed it, as they obey all their impulses, without conscious thought or knowledge of what they are doing or why they are doing it.
Here is some suggestion of a very modern psychology which is inclined to regard the mind as a thought-receiving rather than as a thought-producing instrument, and with that I have some sympathy; but here is also a rejuvenation of the incorporeal swarm instinct and other fantastic or romantic notions of animals which preclude observation. If the anima of a bird or beast is so constituted that it can receive impulses from a mysterious and unknown source, what is to prevent it from receiving such silent impulses from another anima like itself? And why seek an unseen agent for the warning to my caribou or my plover when one of the creatures saw the danger and was enough moved by it to sound a mental tocsin?
The trouble with my friend’s explanation, and with all others I have thus far heard or read, is twofold. First, like the swarm-impulse theory, it really explains nothing, but avoids one mystery or difficulty by taking refuge in another. There was a Hindu philosopher who used to teach, after the manner of his school, that the earth stood [[125]]fast because it rested on the back of a great elephant; which was satisfactory till a thoughtful child asked, “But the elephant, what does he stand on?” So when I see intelligent caribou or plover fleeing from an unsensed danger, and am told that they have received an impulse from without, I am bound to ask, “Where did that impulse come from, and who sent it?” For emotional impulses do not drop like rain from the clouds, or fall like apples from unseen trees; they must have their source in a living, intelligent being of some kind, who must feel the impulse before sending it to others. No other explanation is humanly comprehensible.
This leads to the second objection to the theory of external impulse, and to every other notion of a collective or incorporeal swarm instinct—namely, that it contradicts all the previous experience of the wild creature, or at least all educative experience, which lies plain and clear to our observation. To each bird and animal are given individual senses, individual wit and a personal anima; and each begins his mortal experience not in a great flock or herd, but always in solitary fashion, under the care and guidance of a mother animal that has a saving knowledge of a world in which the little one is a stranger. Thus, I watch the innocent fawn when it begins to follow [[126]]the wary old doe, or the fledgling snipe as it leaves the nest under expert guidance, or the wonder-eyed cub coming forth from its den at the call of the gaunt old she-wolf. In each case I see a mother intelligently caring for her young, leading them to food, warding them from danger, calling them now to assemble or now to scatter; and before my eyes these ignorant youngsters quickly learn to adapt themselves to the mother’s ways and to obey her every signal. Sometimes I see them plainly when some manner of silent communication passes among them (something perhaps akin to that which passes when you catch a friend’s eye and send your thought or order to him across a crowded room), and it has even seemed to me, as recorded elsewhere in our observation of wolf and fox dens, that the young understand this silent communication more readily than they learn the meaning of audible cries expressive of food or danger.
Such is the wild creature’s earliest experience, his training to accommodate himself to the world, and to ways that wiser creatures of his own kind have found good in the world. When his first winter draws near he is led by his mother to join the herd or pack or migrating flock; and he is then ready not for some mysterious new herd or flock instinct, but for the same old signals that have served well to guide or warn him ever since [[127]]he was born. I conclude, therefore, naturally and reasonably, that my caribou broke away and my incoming plover changed their flight because one of their number detected danger and sent forth a warning impulse, which the others obeyed promptly because they were accustomed to just such communications. There was nothing unnatural or mysterious or even new in the experience. So far as I can see or judge, there is no place or need for a collective herd or flock impulse, and the birds and beasts have no training or experience by which to interpret such an impulse if it fell upon them out of heaven.
Our human experience, moreover, especially that which befalls on the borderland of the subconscious world where the wild creatures mostly live, may give point and meaning to our natural philosophy. There are emotions, desires, impulses which may be conveyed by shouting; and there are others which may well be told without shouting, or even without words. A cheerful man radiates cheerfulness; a strong man, strength; a brave man, courage (we do not know to what extent or with what limitations); and a woman may be more irritated by a man who says nothing than by a man who says too much. These common daily trials may be as side-lights on the tremendous fact that love, fear, hate,—every intense emotion is a [[128]]force in itself, a force to be reckoned with, apart from the cry or the look by which it is expressed; that all such emotions project themselves outward; and that possibly, or very probably, there is some definite medium to convey them, as an unknown medium which we call “ether” conveys the waves of light.