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About Beavers

( Originally Published Ealry 1900's )

THE beaver may be said to occupy amongst mammals the place that ants do amongst insects. J. G. Wood says of him: " Of the Social Main malia, he takes the first rank, and is the best possible type of that group. There are other social animals, such as the various marmots and others ; but these creatures live independently of each other, and are only drawn together by the attraction of some favourable locality. The beavers, on the other hand, are not only social by dwelling near each other, but by joining in a work which is intended for the benefit of the community."

As everyone knows, the beaver is an aquatic animal as is sufficiently indicated by his appearance. He has a dense, woolly coat, which, as in the case of the otter and the still more water-loving seals, is protected by an outer covering of long, smooth hairs, which are of a reddish brown colour. The toes of the hind feet are webbed, whilst the tail is broadened out into the shape of a paddle, the blade of which, however, lies fiat on the water, so that it is not used by the animal as we would use a scull or a paddle, but with an upward and downward motion. When the beaver moves his tail laterally — that is to say from side to side—as he is very well able to do, it cuts the water, after the manner and with the same effect that a scull does when worked by a seaman at the stern of the boat, instead of in the rowlocks as we use it.

This tail of the beaver is a very wonderful organ, and by far the most conspicuous feature about the animal. Mr. Morgan, who made à study of beavers and their habitations, says of it : It is nearly flat, and covered with horny scales of a lustrous black. These scales, which are such in appearance only, cover every portion of the surface, both above and underneath. Its principal uses are to elevate or depress the head while swimming, to turn the body and vary its direction, and to assist the animal in diving. It is also used to give a signal of alarm to its mates. When alarmed in his pond, particularly at night, he immediately dives, in doing which the posterior part of his body is thrown out of water, and as he descends head foremost, the tail is brought down upon the surface of the water, with a heavy stroke, and deep below it with a plunge. The violence of the blow is shown by the spray, which is thrown up two or three feet high."

Elsewhere the same authority says: " Whilst watching upon their dams at night I have been startled by this tremendous stroke, which, in the stillness of the hour, seemed like a pistol-shot. I have heard it distinctly for half a mile, and think it can be heard twice or three times that distance, under favourable conditions." That must have been a splendid thing to hear—that sudden, startling blow—in the dead silence of the night, and in the loneliness of the North American wilderness; in the Hudson's Bay territories perhaps—the headquarters of the beaver — where, for hundreds of miles around, there would be no other white man, or even, perhaps, an Indian, within a very great distance. Any other beaver that happened to be about at the time — at any rate, all those that were living in the same pond — when they heard that sound of alarm would go down too in the same way, so that there would be cracks like pistol-shots all about. That would be a concert worth listening to.

But now, what is this pond of the beavers which is referred to by Mr. Morgan in the above passage of his book, The American Beaver and His Works—a most interesting work, which should be read by anyone who wants to know all about beavers? It is made, or rather caused, by the beavers themselves, and this brings us to the dam, which is their principal work, and which they construct for the express purpose of having this pond to live in. They are animals who simply cannot do without water, and as the streams on which they take up their abode are often small and shallow, it is of the greatest consequence to them that they should never run dry—which in a drought or dry summer they might easily do. To prevent this, having first selected a part of the stream where the water is not more than two or three feet deep, they bring earth from the adjacent banks and lay it down in mid-stream. Soft earth of a clayey consistency is preferred, for this, penetrated as it is, and partially held together, by roots and other vegetable fibres, is not at once washed away by the force of the water. The beavers have thus time to add to and strengthen the dam, and the better to effect this object they lay sticks and brushwood upon it, which they then press down into the mud with their feet. To these stones are added, and then more earth and sticks, till at last the crest of the dam appears above the surface of the water, and begins to rise higher and higher. It may attain, at last, to a height of six feet, or even more, above the level of the stream, whilst the length of some dams is as much as two hundred, or even three hundred feet.

The stream itself, at the point where the dam intersects it, may be a few yards in breadth, but as the mass of the flowing water cannot penetrate the solid embankment of mud and sticks which the beavers have made, it broadens out and begins to make a way on either side of it. The beavers, however, to prevent this, keep lengthening the dam, and in this way, as the stream can no longer flow in its channel, and can only get by the obstacle placed in its way, very slowly, by spreading out and flooding the surrounding country, the result is that a great pond or basin of water is formed on the up-stream side of the dam, and this the beavers have all to themselves. Of course, when the water is checked in its flow, it begins to rise against the dam that confines it, and as only a small quantity percolates through, it sinks and runs away in a much smaller volume, on the other side of the obstruction. When a flour-mill, which is to be worked by water-power, is erected by the side of one of our small streams, exactly the same principle is employed, a darn being built across it, from bank to bank, and the water running off by a side-channel.

Beavers, however, existed long before there were any millers, and moreover, they make better dams than our millers do, or, at least, they construct them upon more scientific principles. The mill-dam runs, as a rule, straight across the stream, but the beavers curve theirs a little up into it, so that the water does not rush against it so violently as it would if it were straight, but flows smoothly off upon either side. This is how we make our sea-dams — at least when it is possible—and where any structure has to resist a great force of water, as, for in-stance, the buttresses of a bridge across some large river, it is always shaped like this, only more so; that is to say, we turn the curve into an acute angle and present a sharp edge, instead of a rounded surface, to the impetuous rush of the stream. In this way the water is cut in two, as if by a knife-blade, whereas, if the masonry presented a broad surface for it to rush against the first flood might wash the strongest bridge away. Practical experience seems to have led to the beaver 's employment of the principle, though probably he has no very clear ideas as to what the principle is. He could not " formulate it "—as we say - and to say the truth, neither could I myself at this moment.

Besides the first, or great dam, the beaver sometimes makes a smaller one lower down the stream. This smaller dam is perhaps a more interesting structure even than the principal one, from the point of view of the beaver's intelligence. The pond which is formed above it by the now diminished stream is too small to be of much use to the animal, but by increasing the height of the water behind the great dam, it diminishes the pressure of the stream against it, on the other side, so that there is less fear of the dam's bursting. This, too, is by a principle which I should find it difficult to formulate myself and it can hardly be supposed that the beaver knows any thing about it. The surprising thing is that, somehow, practically, he has found it out— that is to say! he knows how to apply it. In carrying the mud and sticks to the water, the beaver walks, it would seem, upon his hind legs, and in placing and working them together, he generally also assumes the upright attitude. The massive tail, by acting as a base or fulcrum, on which the animal can lean back, enables it to do this with the greatest ease. The toes of the forefeet are not webbed, as are those of the hind ones, nor do they aid in swimming, being then pressed against the body, but are used more as hands, at least for the purposes of architecture. With them the beaver scoops up the mud, and holding it between them or pressed against his throat, walks upright to his dam like a little mannikin in a brown fur coat.

It used to be thought that the broad naked tail served the beaver as a trowel, for the laying and plastering of the mud. This was not so entirely an error as one generally reads it is, since Mr. Morgan tells us that " he uses his tail to pack and compress mud and earth, while constructing a lodge or dam, which he effects by heavy and repeated down-strokes," and he adds, truly enough, " that it performs, in this respect, a most important office, and one not unlike some of the uses of the trowel." This shows that there was really something in the old idea, but it was imagined also that the beaver, besides using his tail as a trowel, actually prepared mortar with it, from mud. This was a fable, but there was much more truth in the general statement, of which this was only an item, than in the learned ex cathedra denial, which denied everything — and so it very often is. As we have seen, both wood and mud enter into the construction of the beaver's dam, besides stones, which do not play so important a part. I have called the wood " sticks " because that is the word usually employed in America, where beaver-dams are often called" stick-dams." But these sticks may be of a considerable size, often rather logs, or, at any rate, branches. Branches, gnawed into various lengths, is what they really are, and to obtain them the beaver, which is a rodent, and armed with two enormous chisel-like. teeth in each jaw, is accustomed to cut down trees, often of a surprising size, when its own is taken into consideration.

Two or more beavers— according to Mr. Morgan ,-L generally assist in the cutting down of a tree. " Although," he says, " I have not succeeded in witnessing the act, I have obtained the particulars from Indians and trappers who have. The usual number engaged in the work is but two of a pair; but they are sometimes assisted by two or three young beavers. It thus appears to be the separate work of a family, instead of the joint work of several families. When but two are engaged they work by turns, and alternately stand on the watch, as is the well-known practice of many animals while feeding or at work. When the tree begins to crackle they desist from cutting, which they afterward continue with caution until it begins to fall, when they plunge into the pond, usually, and wait concealed for a time, as if fearful that the crashing noise of the tree-fall might attract some enemy to the place. The next movement is to cut off the limbs, such as are from two to five and six inches in diameter and reduce them to a proper length, to be moved to the water and transported thence to the vicinity of their winter provisions. Upon this work the whole family engage with the most persevering industry, and follow it up, night after night, till the work is accomplished."

The houses of the beaver look like little round huts, but they are called lodges.

The " beaver-lodge " is shaped something like a bee-hive, but flatter and broader at the base, and the walls and roof are very thick—from four to five feet, as a general rule, but sometimes even thicker. It is made of a mass of poles and sticks, the shoots and branches of which the beavers gnaw off, and then strip away the bark. They press and interweave them together, and plaster them with mud, much in the same way as they make their dams. They thus become fairly solid structures, but still, as the mud cannot get into all the interstices of the sticks, they are sufficiently porous to answer the purposes of ventilation. Inside, the lodge consists of a circular chamber, the floor of which is formed of mud, which is soon pressed hard and worn quite smooth by the feet of its occupants.

These consist of a pair of beavers and their young, and sometimes the young of one or more of these, but the Indians say that it is rare to find more than twelve beavers living together, in the same lodge, because the lodge is not large enough to accommodate more than that number comfortably. From two to five young beavers are born at one time, and when they are two years old, by which time they are almost full-grown, they are not allowed to continue any longer in the parent lodge, but have to go out into the world, to find mates and make lodges for themselves. This, at least, is what the Indians say, and no doubt it must be so, in the greater number of cases. Still as a family of five young beavers, with the two parents, would only make seven in all, and as sometimes more than seven beavers are found living together in one lodge, it seems plain that in these cases some of the young beavers must have stayed in the home circle a little longer, and brought their mates there to live with them. Probably the numbers are in accordance with the size of the interior chamber, for if a beaver felt uncomfortable in his lodge, he would, no doubt, leave it, as we should leave our house or lodgings, but without giving any notice.

As I say, the floor of the beaver-house is of mud, but round the outer border of it, next to the wall, the beavers lay down grass, which they use, both to sleep on and also to make nests for their young. The latter are nourished, for six weeks, by their mother, after which, and for the rest of their lives, they live principally on bark. It is not the thick bark, at the base of the trunks of trees, that beavers like, but that which clothes the smaller limbs, for this is both tenderer and more nutritious. This is one great reason for the cutting down of trees, so that the beaver was, no doubt, a tree-feller before he came to be a dam-builder, for food comes first, both with men and animals, and houses and engineering works afterward.

It might be thought that, as there are trees to be felled both in summer and winter, the beaver, though he does not hibernate, would find no more difficulty in procuring food in the one season than in the other, so that it would not be necessary for him to store up a supply of it, for winter consumption, either in his lodges or at the bottom of his pond. In reality, however, there are difficulties, and "they are compelled," says Mr. Morgan, " to provide a store of subsistence for the long winters of the north, during which their ponds are frozen over, and the danger of venturing upon the land is so largely increased as to shut them up, for the most part, in their habitations." " In preparing for the winter," Mr. Morgan continues, " their greatest efforts in tree-cutting are made. They commence in the latter part of September and continue through October and into November the several employments of cutting and storing their winter food and of repairing their lodges and dams. Part of this winter supply the beaver, as we have seen, brings into his dwelling, and for this purpose he makes a special entrance to it, which facilitates his doing so. Beaver-lodges are always situated on the edge of the water, and it is by diving under water that the beaver goes in and out of them. The lodge enters the water at one point, and, within the space conterminous with it, there are two or more entrances, which open out beneath its surface at a sufficient depth for the water not to be frozen during the winter; since, if this were the case, the inmates would perish, the walls being, at this time, too hard and solid even for a beaver's teeth.

These entrances are made," says Mr. Morgan, " with great skill and in the most artistic manner. In new lodges there is generally but one, but others are added, with their increase in size, under the process of repairing, until in large lodges there are sometimes three or four. These entrances are of two kinds, one straight and the other sinuous. The first we shall call ` the wood en-trance,' from the beavers' evident design to facilitate the admission into their chamber of the wood-cuttings upon which they subsist, during the season of winter. These cuttings are of such size and length that such an entrance is absolutely necessary for their free admission into the lodge. The other, which we shall call ` the beaver entrance ' " is the ordinary one for the exit and return of the animal."

Some beavers make a trench all round their huts, and let the water from the pond run into it. Then they make one passage out into the water of this trench, and another into that of the pond. Mr. Wood, in speaking of the beaver-lodges, tells us that " they are nearly circular in form, and much resemble the wellknown snow-houses of the Esquimaux, being domed, and about half as high as they are wide, the average height being three feet, and the diameter six or seven feet. These are the interior dimensions, the exterior measurement being much greater on account of the great thickness of the walls, which are continually strengthened with mud and branches, so that, during the severe frosts, they are nearly as hard as solid stone. All these precautions, however," he goes on to say, " are useless against the practised skill of the trappers. Even in winter time the beavers are not safe. The hunters strike the ice smartly, and judge by the sound whether they are near an aperture. As soon as they are satisfied, they cut away the ice and stop up the opening, so that if the beavers should be alarmed they cannot escape into the water. They then proceed to the shore, and by repeated soundings trace the course of the beaver's subterranean passage, which is sometimes eight or ten yards in length, and by watching the various apertures are sure to catch the beavers. This is not a favourite task with the hunters, and is never undertaken as long as they can find any other employment, for the work is very severe, the hardships are great, and the price which they obtain for the skins is now very small." I heartily wish it were nothing, for then this most interesting and intelligent animal would not be in danger of extermination, as I fear it is now.

The greater number of men and women are, unfortunately, quite callous in regard to what is done to wild animals. They do not see that it is a crime to rob a being of its life — only a human being; though the distinction, nowadays, is one without a difference. To read, first, of what the beavers do, and then of what we do to them, ought to upset one more than the fall of a ministry, or people in one's pew—but it doesn't.

Besides his lodge, or hut, the beaver has his burrow, and there are some beavers which only use their burrows to live in, and do not make a hut at all. The European beaver is now, unfortunately, almost extinct, at least in civilised Europe, but where it does still exist it is not often known to practise house-building. It could hardly have done so in ancient times, since Pliny, the Roman naturalist, who describes its habits, says nothing about this one. He would have done so, we may be sure, had he known of its existence, and as he was a most eager inquirer, and beavers were common enough in Europe then, he could have had no difficulty in finding out all about them, even if he had not been able to study them for himself. The European beaver, therefore, is in the same state as those American beavers which do not make huts, but just as these latter are exceptional in America, so a few beavers here have been seen making huts, like the American ones. The habit, no doubt, has been gradually evolved, and may have begun by some beavers driving their passages so far through the bank in an upward direction, that at last they broke through the surface, and had to be covered in. It is a curious fact that man, in very early times, lived in caves, and after that made a sort of house underground— a burrow, in fact—so that his habitations may have gone through the same process of development as have those of the beavers only with him it has been carried a little farther.

Beavers that do not build houses are called by the French-Canadian trappers paresseux, or idlers. Such individuals do not make dams either, for they live by large and deep rivers, whose course it would be impossible for them to stem. In the banks of these rivers they make their burrows, and live a more or less solitary life. I have just stated my own views in regard to these primitive animals, but the Indians have another way of ac-counting for them, which has nothing to do with evolution or development. Their idea is that, after a certain time, the young beavers are expelled from the family lodge by their parents, who wish them to marry and have children. If, however, they fail to do this, their parents receive them back into the lodge again, but make them, as a punishment, do all the work of repairing the dam. On the following summer they are sent out again to marry, but if again unsuccessful in their wooing, they are not received a second time, but are expelled from the community, and become " outcast beavers." Thus, according to the Indians and their story is, or was, confirmed by the trappers—there are both outcast beavers and slave-beavers. Ants, as we know, make slaves, and it would be curious if beavers, which so much resemble ants in their social habits, joined to their great architectural and engineering skill, were to imitate them, also, in this the most remarkable of their institutions. We cannot, with the example of ants before us, say that this is impossible; but no real evidence of it, as far as I know, has been adduced, unless we take the belief of the Indians as such ; Indians, like other savages, are close observers of animals, but then, they have all sorts of wild legends and fairy-tales about them, as well.

But this fairy-tale of the slave-beavers — if we consider it as such—is told not only by the Indians, but by another and very different people who live far away from them, and whom they could never, in old times, have seen, unless, indeed, the Arabs discovered America. Six or seven hundred years ago, an Arabian author, named Kazwini, wrote a work called the Wanders of Creation, and in it he says, "The beaver (kundur) is a land and water animal that is found in the smaller rivers of the country Isa. On the banks of these he builds a house, and in it he makes for himself an elevated placé, in the form of a bench; then on the right hand, about , step lower, one for his wife, and, on the left, one for his young ones, and, on the lower part of the house, one for his servants. His dwelling possesses, in the lower part, an egress toward the water, and another higher one towards the land. If, therefore, an enemy comes on the water side, or the water rises, he escapes by the egress leading to the land ; but if the enemy comes on the land side, by that which leads to the water. He nourishes himself on the flesh of fishes and the wood of the chelendech (l willow). The merchants of that country are able to distinguish the skins of the servants from those of the masters; the former hew the chelendech wood for their masters, drag it with their mouths, and break it in pieces with their foreheads, so that, in consequence of this office, the hair of the head falls out on the right and left side. The merchants, who are aware of this fact, recognise in the hair of the forehead, thus rubbed off, the skin of the servant. In the skin of the master this mark of recognition is wanting, as he employs himself with catching fish."

We do not quite know where the " country of Isa " lay, but beavers, at that time, were common not only in Europe, and the more northern parts of Asia—as Siberia — but southwards, in Asia Minor, as well, as far as to the river Euphrates. It is probably the beavers in these southern parts, which were nearest to his own country, that this Arabian writer was thinking of, and we see that he makes the animal build a house. The probability is that, over such a vast extent of country, the habits of beavers differed a good deal, as perhaps they do now, in the places where they still remain.

We have seen the beaver as a dam-maker and a house-builder, but we have not yet considered him as a maker of canals. In the construction of the dam and lodge, a great quantity of wood is required, and when the trees do not grow very thickly, those on the edge of the pond are soon cut down and made use of, and gradually, as more and more fall, the beavers have to go farther and farther away from the water, in order to procure fresh timber. To transport this felled timber, overland, to the pond be. comes a more and more laborious task, and at last an impossible one, many of the logs made use of being of great size, when compared with that of the beaver itself. To overcome this difficulty, the beaver sets to work and excavates a trench or cutting in the ground, about three feet wide and as many deep. Commencing it at the brink of the pond, he carries it on to the spot where the trees he covets are growing, and when these, in their turn, have been cut down, he lengthens it till it reaches others, and so on, following the trees as they gradually recede from, the neighbourhood of the pond. Of course the water runs up into the channel thus excavated, so that now, when the beaver has cut up his logs, he has only to float them down the canal that he has so cleverly excavated. This he does by swimming with them in his mouth, or pushing them in front of him with his paws and nose; the water (though there is no current to help) offers very little resistance, and it is now quite an easy matter. Both the trappers and the Indians call these cuttings canals; and canals they are, it is obvious, just as much as those we make for barges to ply on. According to the size of the pond, and the scarcity or otherwise of the trees near its banks, will be the number of the canals made from it by the beavers. A pond figured in Mr. Morgan's book has five, at. different points, all round it, and some might have a great many more. One that Mr. Morgan speaks of was close on six hundred feet, and there are some that are longer.

Beavers live together, not in large numbers, as used to be supposed, but two or three families in the same pond. Such ponds, however, continue to be inhabited by the descendants of such families, from generation to generation, and as the dams are always being repaired and extended by them, and the canals lengthened, they at last become works of considerable magnitude. No one who first saw one of these great, ancient beaver-dams would suppose it to be the work of comparatively small animals, or, indeed, of any animal at all, except man. As for the canals, their banks soon become covered with moss and vegetation, so that they look like natural sluggish streams, oozing through the flat, marshy land. Mr. Morgan, speaking of them, says : " When I first came upon these canals, and found they were christened with this name, both by Indians and trappers, I doubted their artificial character, and supposed them referable to springs as their producing cause; but their form, location, and evident object showed conclusively that they were beaver excavations."

There is one other thing that the beavers make, besides their dams, their lodges, and their canals, and that is their meadows ; but beaver-meadows, as they are called, are not the result of design on the part, of the animal, but only the necessary consequence of its actions in other respects. Their appearance, and the way in which they are caused, are thus described by Mr. Morgan : " Where dams are constructed," he tells us, " the waters first destroy the timber within the area covered by the ponds. When the adjacent lands are low, they are occasionally overflowed after heavy rains, and are at all times saturated with water from the ponds. In course of time the trees within the area affected are totally destroyed; and in their place a rank, luxuriant grass springs up. A level meadow, in the strict and proper sense of the term, is thus formed; although much unlike the meadow of the cultivated farm. At a distance they appear to be level and smooth; but when you attempt to walk over them, they are found to be a series of hummocks, formed of earth and a mass of coarse roots of grass rising about a foot high, while around each of them there is a narrow strip of bare and sunken ground. The bare spaces, which are but a few inches wide, have the appearance of innumerable watercourses, and through them the water passes when the meadows are overflowed."

These meadows, though not designed by the beavers, are yet useful to them, for, as Mr. Morgan says : " In addition to the nutriment which the roots of these grasses afford to the beavers, the meadows themselves are clearings in the wilderness, by means of which the light as well as the heat of the sun is let in upon their lodges." Of course, when land that was once dry becomes overflowed with water, when peculiar-looking meadows appear, that were not there before, when canals wind about through them, and when trees that were formerly abundant grow thinner or even disappear, a considerable change takes place in the appearance of the country; and so numerous, till lately, were beavers in North America, that a very large extent of territory may be said to be the work, not, indeed, of their hands, but of their paws and teeth. Sometimes the Indians have been alarmed at the number of trees cut down by these animals, thinking they would not have sufficient fuel for their own encampments, but here, I think, they must have feared without cause, since beavers and trees have both been plentiful in the country from time immemorial.

On one occasion, however, by making a dam across a small stream running parallel with one of the principal railway lines of Canada, the beavers produced an accumulation of water against the railway embankment. As it was feared that the line might be flooded, or the earth supporting it weakened, with possible disastrous consequences, a cutting was made through the centre of the dam, thus lowering the water to its original level. The beavers, however, were accustomed to repairing their dams, and did so in this instance. The company again cut the dam, the beavers again repaired it, and this conflict between an animal and one of their chief commercial enterprises of the country continued, till the dam, having been fifteen times cut through, was at length abandoned by its architects. This shows, certainly, great perseverance on the part of the beavers, but it shows also that they are capable of learning by experience.

The beaver is the second largest animal of the order of rodents or gnawing animals, of which the most familiar examples are the rat and the mouse, the first being the great capybara of South America, which creature weighs as much as ninety or even one hundred lbs. The beavers, when full grown, may weigh as much as fifty, but it is rare for one to attain this size. Though usually of a reddish brown, black beavers are sometimes met with, and white ones, though extremely rare, are not absolutely unknown. Traherne in his Journey to the Northern Ocean says : " In the course of twenty years' experience in the countries about Hudson's Bay, though I have travelled six hundred miles to the west of the sea-coast, I never saw but one white beaver-skin, and it had many reddish and brown hairs along the ridge of the back. The sides and the belly were of a glossy, silvery white." Prince Maximilian, too, who also travelled in North America, says that he " saw one beautifully spotted with white," and that " yellowish white and pure white ones are not unfrequently caught on the Yellowstone." This, however, was a long time ago. Not only white beavers, but brown ones too are getting rare now.

Beavers are nocturnal, so that it is not so easy to see them working at their dams and lodges as it might otherwise be. However, it would not be very easy, even if they worked in the day, for persecution has made them extremely shy and wary, and perhaps has even had something to do with their habits in this respect. On land the beaver is somewhat awkward, and not at all fast, so that, though he is able to gallop, an ordinary dog could soon run him down. The water is his more natural element, and here he is easy and graceful. His sight, at least in the daytime, is not very good, but his smell and his hearing are most acute. Upon the latter sense he relies so much that he will often choose out some little hillock or rising piece of ground, where he will sit up on his hind legs like a sentinel, listening attentively. Then, says Mr. Morgan, his best biographer, " 0 he will retire, but only to return at intervals, and repeat the observation until satisfied whether or not danger is near." With this interesting trait we will take our leave of this most interesting and badly treated animal.

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