Popular Science Monthly/Volume 4/November 1873/The Survival of Instincts
|THE SURVIVAL OF INSTINCTS.|
ANIMAL life has its episodes, and apparently abnormal habits. A gentleman, residing near this city (Brooklyn), had recently a turkey tethered with a cord in a field during the early life of her brood. He had also several other turkeys with which this one had a long time associated, apparently on the most friendly terms, and which, during her temporary confinement, strolled and fed quietly around her. But it happened one day that she became entangled with the cord, so that her feet were drawn together, and, being unable to walk, lay struggling on the ground. While thus helpless her associates attacked her, evidently for the purpose of killing her outright. They made no onset as when fighting, but deliberately and in the coolest manner possible commenced their butchery by picking the head of the unfortunate bird.
So intent were they that they scarcely heeded the approach of our friend, who, from a distance, saw what was going on. Before he reached the spot, the assailants had destroyed one eye and laid bare the skull, inflicting injuries so great upon the creature that she soon died. A similar act was repeated shortly afterward in the same flock, and the phenomenon—certainly a curious one—is, we believe, not unusual.
Observation and inquiry have shown that a like disposition appears not among turkeys only, but in several species of animals, exciting them, when aroused, to attack and worry those of their kind if weak, sick, or disabled. It has been noticed with cattle, swine, dogs, and, as has been suggested by observers, may occur with all domesticated or partly domesticated species in which it had existed in their wild state. We are informed by drovers, of whom we have made careful inquiry, that when herds of cattle are hurriedly driven, and especially when they become excited or alarmed, one having fallen, or showing signs of weakness, is sometimes set upon and gored by its associates.
Two gentlemen, who have been drovers forty years, and during many years were themselves collectors and drivers of herds, assure us that they have often witnessed such attacks, and have interfered to prevent injury. They also state that the habit appears to be more frequent with animals which have run at large without much care or restraint, than with those well domesticated.
Such occurrences, however, are well known among domesticated cattle. A gentleman residing on Long Island had, a few years since, a herd of cattle, one of which was taken suddenly sick, but was turned, as usual, into the field with the others. In a short time he noticed great disturbance among them, and, on hurrying to the spot, found the sick one on the ground bellowing, and being gored by her associates. An acute observer, also residing on Long Island, near this city, Mr. J. D. Hicks, writes as follows: "In answer to thy inquiries, J. H. and S. R. inform me that the fact has been noticed in their own experience that the well ones of a herd do sometimes seek to gore and destroy a sick or maimed one. A cry of distress, instead of exciting sympathy, seems to invite attack, and the first movement by one is a signal for attack by others. Thee may rest perfectly assured of this. I have myself more than once witnessed it."
The gentlemen whose initials are given are large owners of cattle, and have for nearly half a century been familiar with their habits, and with the habits of those brought in droves from distant parts of the country. Of the habits of entirely wild cattle we know but little. The wild herds of the pampas have descended from tame stock, and it is not easy to show by instances the habits of the original wild stock in this particular. A breed of cattle formerly common in Southern Scotland, noted for their untamed and savage disposition, is spoken of by Cuvier, under the name of white urus, and he says: "When one of this breed happens to be wounded, or is enfeebled by age or sickness, the others set upon it and gore it to death."
With swine a similar habit has been observed. We are informed that it is sometimes necessary to separate disabled ones, for safety, from the general herd. The drovers already referred to state that, in the driving and transportation of swine, those which become sick and faint are often objects of attack. Drooping of the ears, and other evidences of exhaustion, seem to excite the propensity, and may occur while being driven, or in pens in course of transportation. In cars, where they are probably much excited, weak and fallen ones are often torn to pieces, and sometimes devoured.
On one occasion, after a sick pig was thus disposed of, a dead dog was thrown among the excited animals, but no notice was taken of it. We will mention, in this connection, that we have not learned of any instance of an animal, strong and vigorous, being thus attacked, nor where a sick or feeble one was defended by its associates when such an attack was made; and it is certain that with hogs, as with cattle, the more untamed they are, the more violent and savage is their disposition, and the more frequent the peculiar habit we have under consideration.
Audubon observes that, with the wild-turkey, the old males, on their marches, frequently destroy, by picking the head, those which are immature, but it does not appear that full-grown and vigorous birds are attacked. The old, sick, and disabled, are continually left to their fate by moving herds of the American bison, and are fed upon by wolves. That they are expelled by violence is probable, but, so far as we know, there is no positive proof of the fact. It is known that wolves, if wounded, are attacked and killed by their comrades; and the arctic fox, if disabled, is sometimes not only destroyed, but eaten by its companions. One of a school of porpoises at play around a vessel, as we once witnessed, was injured by a pole hurled at it, when it was instantly pursued by dozens of others with a celerity of movement that was astonishing.
Darwin, commenting on this trait in animals, says: "It is almost the blackest fact in natural history that animals should expel a wounded one from the herd, or gore or worry it to death."
That the helpless and suffering should be thus destroyed does indeed seem to indicate an absence of sympathy in strange contrast with the kindness and affection shown in innumerable instances between animals of the same species. But the kind-hearted author already cited remarks that "instinct or reason may suggest the expelling an injured companion, lest beasts of prey, including man, should be tempted to follow the troop. In this case their conduct is not much worse than that of the North American Indians, who leave their feeble comrades to perish on the plains, or the Feejeeans, who, when their parents get old or fall ill, bury them alive."
If the view of Darwin be correct, it is evident that the habit originated in the wild and undomesticated state of the species, and that, in destroying their disabled or wounded ones, they simply act out their instinct of self-preservation.
They get rid of those which might delay their flight or allure pursuit; and we may conclude that love of life and fear of danger, rather than any primal ferocity, develop and fix a habit which at first sight appears singular and unaccountably savage.
Animals in their wild state live in perpetual danger, and, we may add, in perpetual fear. Sir John Richardson observes that wolves continually haunt the track of the buffalo, and the weak are often seized. The peccary, says Cuvier, if it falls in the rear of the flock, is seized by the jaguar, and the feeble, straggling ones of every herd become a prey to its enemies, and incite pursuit. It would be strange, indeed, if this source of danger, so obvious and persistent, should escape the sagacity of animals, or be disregarded by their prudence. We know that animals of many kinds defend each other, and thus protect themselves. The habit referred to is merely a method of defense. The courageous and strong stand guard over the herd or flock in time of danger, and the intelligence or instinct which prompts this also prompts the removal of an element of weakness.
Nor do animals differ in this respect from man. Does history furnish no instances where commanders of armies have sacrificed the wounded, and destroyed by poison or otherwise the weak and helpless that the strong might escape destruction? Equally with animals and with man, danger may suggest and put in execution means for securing safety, which show a strange absence of sympathy in the one case, and of humanity in the other.
It is not probable that animals possess savage qualities other than such as are or were originally of service to them and their kind. We cannot understand that any quality or habit should be developed in an animal which was not serviceable to it; but it is certain that both may arise from the wants and necessities incident to its condition.
If strength and fleetness are essential in pursuit, so also is sagacity in eluding it. An element of danger is detected and removed. A fox will use every precaution that the hound may not be allured by his odor, and the white urus destroys its weak comrade which falls in the rear unable to maintain its place in the flight. The habit with some animals of destroying their weak companions is only one of many which by repetition becomes at last common to the kind. With the repetition of the act grows a disposition or tendency to repeat it as the exciting cause or condition recurs. It becomes thus in the creature a tendency which we may term instinctive, and that such tendencies are transmissible and are inherited needs no illustration here. Perhaps there is no fact in biology more clearly established and more fearfully significant than this, and it is true equally in man and in the lower animals.
Habits thus developed do not readily disappear, but the old disposition or instinct may remain after the habit has been discontinued, and long after it has ceased to be of service to the creature. This is shown by the fact that former habits frequently reappear when suggested by former predisposing conditions, although these may have been long overlooked or forgotten.
Under domestication many habits indispensable to animals in their wild state become useless, and slowly but surely disappear, while others are developed, and the animal undergoes a physical and mental change; but the time is very long before old instincts die out beyond the possibility of resuscitation. They appear to continue in animals under domestication as do those of the savage, in civilized life, despite culture and education. We will illustrate by a single instance:
With the savage, hunting is the occupation of life. He hunts from necessity, and his mental, moral, and physical being, are attuned to its conditions. His hunting habits and hunting dispositions are thoroughly instinctive, but in civilized communities the necessity for hunting has chiefly disappeared. Still, the field and forest are hunting-grounds. The savage is not there, but who will say that the old instincts have not survived in the cunning of pursuit, the thoughtless cruelty of destruction, and indifference to suffering? It is true our modern hunter has grown gentle, humane, and tender, in a thousand directions, but the enjoyment of him who hunts merely for sport cannot be in that spirit which has developed with his culture—which weeps at the sight of agony, and is tender to the "mournful eloquence of pain."
We refer to this only to illustrate the persistence of instinctive tendencies, and of the habits with which mental states seem directly associated.
It is, we believe, probable, perhaps certain, that the disposition in some animals to destroy their weak associates has come down from a former undomesticated condition of their kind, in which its correlative habits were essential to safety and life.
If this view be correct, our friend's birds may not be obnoxious to the charge of being specially cruel; and, seeing how persistent instinctive habits may become in some of the higher animals and in man, it is not strange that they continue in the turkey, a species recently domesticated, and by no means remarkable for intelligence.