The Wonders of Instinct Part 4

Presently the sand which has been pushed outward quivers under the thrust of the invisible miners, slips into the pit and covers the interred Mole. It is a clandestine burial. The body seems to disappear of itself, as though engulfed by a fluid medium. For a long time yet, until the depth is regarded as sufficient, the body will continue to descend.

It is, when all is taken into account, a very simple operation. As the diggers, underneath the corpse, deepen the cavity into which it sinks, tugged and shaken by the s.e.xtons, the grave, without their intervention, fills of itself by the mere downfall of the shaken soil.

Useful shovels at the tips of their claws, powerful backs, capable of creating a little earthquake: the diggers need nothing more for the practice of their profession. Let us add--for this is an essential point--the art of continually jerking and shaking the body, so as to pack it into a lesser volume and cause it to pa.s.s when pa.s.sage is obstructed. We shall presently see that this art plays a part of the greatest importance in the industry of the Necrophori.

Although he has disappeared, the Mole is still far from having reached his destination. Let us leave the undertakers to complete their task.

What they are now doing below ground is a continuation of what they did on the surface and would teach us nothing new. We will wait for two or three days.

The moment has come. Let us inform ourselves of what is happening down there. Let us visit the retting-vat. I shall invite no one to be present at the exhumation. Of those about me, only little Paul has the courage to a.s.sist me.

The Mole is a Mole no longer, but a greenish horror, putrid, hairless, shrunk into a round, greasy ma.s.s. The thing must have undergone careful manipulation to be thus condensed into a small volume, like a fowl in the hands of the cook, and, above all, to be so completely deprived of its fur. Is this culinary procedure undertaken in respect of the larvae, which might be incommoded by the fur? Or is it just a casual result, a mere loss of hair due to putridity? I am not certain. But it is always the case that these exhumations, from first to last, have revealed the furry game furless and the feathered game featherless, except for the tail-feathers and the pinion-feathers of the wings.

Reptiles and fish, on the other hand, retain their scales.

Let us return to the unrecognizable thing which was once a Mole. The t.i.t-bit lies in a s.p.a.cious crypt, with firm walls, a regular workshop, worthy of being the bake-house of a Copris-beetle. Except for the fur, which is lying in scattered flocks, it is intact. The grave-diggers have not eaten into it; it is the patrimony of the sons, not the provision of the parents, who, in order to sustain themselves, levy at most a few mouthfuls of the ooze of putrid humours.

Beside the dish which they are kneading and protecting are two Necrophori; a couple, no more. Four collaborated in the burial. What has become of the other two, both males? I find them hidden in the soil, at a distance, almost at the surface.

This observation is not an isolated one. Whenever I am present at a burial undertaken by a squad in which the males, zealous one and all, predominate, I find presently, when the burial is completed, only one couple in the mortuary cellar. Having lent their a.s.sistance, the rest have discreetly retired.

These grave-diggers, in truth, are remarkable fathers. They have nothing of the happy-go-lucky paternal carelessness that is the general rule among insects, which plague and pester the mother for a moment with their attentions and thereupon leave her to care for the offspring! But those who in the other races are unemployed in this case labour valiantly, now in the interest of their own family, now for the sake of another's, without distinction. If a couple is in difficulties, helpers arrive, attracted by the odour of carrion; anxious to serve a lady, they creep under the body, work at it with back and claw, bury it and then go their ways, leaving the householders to their happiness.

For some time longer these latter manipulate the morsel in concert, stripping it of fur or feather, trussing it and allowing it to simmer to the taste of the larvae. When all is in order, the couple go forth, dissolving their partners.h.i.+p, and each, following his fancy, recommences elsewhere, even if only as a mere auxiliary.

Twice and no oftener hitherto have I found the father preoccupied by the future of his sons and labouring in order to leave them rich: it happens with certain Dung-beetles and with the Necrophori, who bury dead bodies. Scavengers and undertakers both have exemplary morals. Who would look for virtue in such a quarter?

What follows--the larval existence and the metamorphosis--is a secondary detail and, for that matter, familiar. It is a dry subject and I shall deal with it briefly. About the end of May, I exhume a Brown Rat, buried by the grave-diggers a fortnight earlier. Transformed into a black, sticky jelly, the horrible dish provides me with fifteen larvae, already, for the most part, of the normal size. A few adults, connections, a.s.suredly, of the brood, are also stirring amid the infected ma.s.s. The period of hatching is over now; and food is plentiful. Having nothing else to do, the foster-parents have sat down to the feast with the nurselings.

The undertakers are quick at rearing a family. It is at most a fortnight since the Rat was laid in the earth; and here already is a vigorous population on the verge of the metamorphosis. Such precocity amazes me. It would seem as though the liquefaction of carrion, deadly to any other stomach, is in this case a food productive of especial energy, which stimulates the organism and accelerates its growth, so that the victuals may be consumed before its approaching conversion into mould. Living chemistry makes haste to outstrip the ultimate reactions of mineral chemistry.

White, naked, blind, possessing the habitual attributes of life in darkness, the larva, with its lanceolate outline, is slightly reminiscent of the grub of the Ground-beetle. The mandibles are black and powerful, making excellent scissors for dissection. The limbs are short, but capable of a quick, toddling gait. The segments of the abdomen are armoured on the upper surface with a narrow reddish plate, armed with four tiny spikes, whose office apparently is to furnish points of support when the larva quits the natal dwelling and dives into the soil, there to undergo the transformation. The thoracic segments are provided with wider plates, but unarmed.

The adults discovered in the company of their larval family, in this putridity that was a Rat, are all abominably verminous. So s.h.i.+ny and neat in their attire, when at work under the first Moles of April, the Necrophori, when June approaches, become odious to look upon. A layer of parasites envelops them; insinuating itself into the joints, it forms an almost continuous surface. The insect presents a misshapen appearance under this overcoat of vermin, which my hair-pencil can hardly brush aside. Driven off the belly, the horde make the tour of the sufferer and encamp on his back, refusing to relinquish their hold.

I recognize among them the Beetle's Gamasis, the Tick who so often soils the ventral amethyst of our Geotrupes. No; the prizes of life do not fall to the share of the useful. Necrophori and Geotrupes devote themselves to works of general salubrity; and these two corporations, so interesting in the accomplishment of their hygienic functions, so remarkable for their domestic morality, are given over to the vermin of poverty. Alas, of this discrepancy between the services rendered and the harshness of life there are many other examples outside the world of scavengers and undertakers!

The Burying-beetles display an exemplary domestic morality, but it does not persist until the end. During the first fortnight of June, the family being sufficiently provided for, the s.e.xtons strike work and my cages are deserted, so far as the surface is concerned, in spite of new arrivals of Mice and Sparrows. From time to time some grave-digger leaves the subsoil and comes crawling languidly in the fresh air.

Another rather curious fact now attracts my attention. All, as soon as they emerge from underground, are cripples, whose limbs have been amputated at the joints, some higher up, some lower down. I see one mutilated Beetle who has only one leg left entire. With this odd limb and the stumps of the others lamentably tattered, scaly with vermin, he rows himself, as it were, over the dusty surface. A comrade emerges, one better off for legs, who finishes the cripple and cleans out his abdomen. So my thirteen remaining Necrophori end their days, half-devoured by their companions, or at least shorn of several limbs.

The pacific relations of the outset are succeeded by cannibalism.

History tells us that certain peoples, the Ma.s.sagetae and others, used to kill their aged folk in order to spare them the miseries of senility. The fatal blow on the h.o.a.ry skull was in their eyes an act of filial piety. The Necrophori have their share of these ancient barbarities. Full of days and henceforth useless, dragging out a weary existence, they mutually exterminate one another. Why prolong the agony of the impotent and the imbecile?

The Ma.s.sagetae might invoke, as an excuse for their atrocious custom, a dearth of provisions, which is an evil counsellor; not so the Necrophori, for, thanks to my generosity, victuals are superabundant, both beneath the soil and on the surface. Famine plays no part in this slaughter. Here we have the aberration of exhaustion, the morbid fury of a life on the point of extinction. As is generally the case, work bestows a peaceable disposition on the grave-digger, while inaction inspires him with perverted tastes. Having no longer anything to do, he breaks his fellow's limbs, eats him up, heedless of being mutilated or eaten up himself. This is the ultimate deliverance of verminous old age.

CHAPTER 6. THE BURYING-BEETLES: EXPERIMENTS.

Let us proceed to the rational prowess which has earned for the Necrophorus the better part of his renown and, to begin with, let us submit the case related by Clairville--that of the too hard soil and the call for a.s.sistance--to experimental test.

With this object in view, I pave the centre of the s.p.a.ce beneath the cover, level with the soil, with a brick and sprinkle the latter with a thin layer of sand. This will be the soil in which digging is impracticable. All about it, for some distance and on the same level, spreads the loose soil, which is easy to dig.

In order to approximate to the conditions of the little story, I must have a Mouse; with a Mole, a heavy ma.s.s, the work of removal would perhaps present too much difficulty. To obtain the Mouse I place my friends and neighbours under requisition; they laugh at my whim but none the less proffer their traps. Yet, the moment a Mouse is needed, that very common animal becomes rare. Braving decorum in his speech, which follows the Latin of his ancestors, the Provencal says, but even more crudely than in my translation: "If you look for dung, the a.s.ses become constipated!"

At last I possess the Mouse of my dreams! She comes to me from that refuge, furnished with a truss of straw, in which official charity gives the hospitality of a day to the beggar wandering over the face of the fertile earth; from that munic.i.p.al hostel whence one invariably emerges verminous. O Reaumur, who used to invite marquises to see your caterpillars change their skins, what would you have said of a future disciple conversant with such wretchedness as this? Perhaps it is well that we should not be ignorant of it, so that we may take compa.s.sion on the sufferings of beasts.

The Mouse so greatly desired is mine. I place her upon the centre of the brick. The grave-diggers under the wire cover are now seven in number, of whom three are females. All have gone to earth: some are inactive, close to the surface; the rest are busy in their crypts. The presence of the fresh corpse is promptly perceived. About seven o'clock in the morning, three Necrophori hurry up, two males and a female. They slip under the Mouse, who moves in jerks, a sign of the efforts of the burying-party. An attempt is made to dig into the layer of sand which hides the brick, so that a bank of sand acc.u.mulates about the body.

For a couple of hours the jerks continue without results. I profit by the circ.u.mstance to investigate the manner in which the work is performed. The bare brick allows me to see what the excavated soil concealed from me. If it is necessary to move the body, the Beetle turns over; with his six claws he grips the hair of the dead animal, props himself upon his back and pushes, making a lever of his head and the tip of his abdomen. If digging is required, he resumes the normal position. So, turn and turn about, the s.e.xton strives, now with his claws in the air, when it is a question of s.h.i.+fting the body or dragging it lower down; now with his feet on the ground, when it is necessary to deepen the grave.

The point at which the Mouse lies is finally recognized as una.s.sailable. A male appears in the open. He explores the specimen, goes the round of it, scratches a little at random. He goes back; and immediately the body rocks. Is he advising his collaborators of what he has discovered? Is he arranging matters with a view to their establis.h.i.+ng themselves elsewhere, on propitious soil?

The facts are far from confirming this idea. When he shakes the body, the others imitate him and push, but without combining their efforts in a given direction, for, after advancing a little towards the edge of the brick, the burden goes back again, returning to the point of departure. In the absence of any concerted understanding, their efforts of leverage are wasted. Nearly three hours are occupied by oscillations which mutually annul one another. The Mouse does not cross the little sand-hill heaped about it by the rakes of the workers.

For the second time a male emerges and makes a round of exploration. A bore is made in workable earth, close beside the brick. This is a trial excavation, to reveal the nature of the soil; a narrow well, of no great depth, into which the insect plunges to half its length. The well-sinker returns to the other workers, who arch their backs, and the load progresses a finger's-breadth towards the point recognized as favourable. Have they done the trick this time? No, for after a while the Mouse recoils. No progress towards a solution of the difficulty.

Now two males come out in search of information, each of his own accord. Instead of stopping at the point already sounded, a point most judiciously chosen, it seemed, on account of its proximity, which would save laborious transportation, they precipitately scour the whole area of the cage, sounding the soil on this side and on that and ploughing superficial furrows in it. They get as far from the brick as the limits of the enclosure permit.

They dig, by preference, against the base of the cover; here they make several borings, without any reason, so far as I can see, the bed of soil being everywhere equally a.s.sailable away from the brick; the first point sounded is abandoned for a second, which is rejected in its turn.

A third and a fourth are tried; then another and yet another. At the sixth point the selection is made. In all these cases the excavation is by no means a grave destined to receive the Mouse, but a mere trial boring, of inconsiderable depth, its diameter being that of the digger's body.

A return is made to the Mouse, who suddenly quivers, oscillates, advances, recoils, first in one direction, then in another, until in the end the little hillock of sand is crossed. Now we are free of the brick and on excellent soil. Little by little the load advances. This is no cartage by a team hauling in the open, but a jerky displacement, the work of invisible levers. The body seems to move of its own accord.

This time, after so many hesitations, their efforts are concerted; at all events, the load reaches the region sounded far more rapidly than I expected. Then begins the burial, according to the usual method. It is one o'clock. The Necrophori have allowed the hour-hand of the clock to go half round the dial while verifying the condition of the surrounding spots and displacing the Mouse.

In this experiment it appears at the outset that the males play a major part in the affairs of the household. Better-equipped, perhaps, than their mates, they make investigations when a difficulty occurs; they inspect the soil, recognize whence the check arises and choose the point at which the grave shall be made. In the lengthy experiment of the brick, the two males alone explored the surroundings and set to work to solve the difficulty. Confiding in their a.s.sistance, the female, motionless beneath the Mouse, awaited the result of their investigations. The tests which are to follow will confirm the merits of these valiant auxiliaries.

In the second place, the point where the Mouse lay being recognized as presenting an insurmountable resistance, there was no grave dug in advance, a little farther off, in the light soil. All attempts were limited, I repeat, to shallow soundings which informed the insect of the possibility of inhumation.

It is absolute nonsense to speak of their first preparing the grave to which the body will afterwards be carted. To excavate the soil, our grave-diggers must feel the weight of their dead on their backs. They work only when stimulated by the contact of its fur. Never, never in this world do they venture to dig a grave unless the body to be buried already occupies the site of the cavity. This is absolutely confirmed by my two and a half months and more of daily observations.

The rest of Clairville's anecdote bears examination no better. We are told that the Necrophorus in difficulties goes in search of a.s.sistance and returns with companions who a.s.sist him to bury the Mouse. This, in another form, is the edifying story of the Sacred Beetle whose pellet had rolled into a rut, powerless to withdraw his treasure from the gulf, the wily Dung-beetle called together three or four of his neighbours, who benevolently recovered the pellet, returning to their labours after the work of salvage.

The exploit--so ill-interpreted--of the thieving pill-roller sets me on my guard against that of the undertaker. Shall I be too exigent if I enquire what precautions the observer adopted to recognize the owner of the Mouse on his return, when he reappears, as we are told, with four a.s.sistants? What sign denotes that one of the five who was able, in so rational a manner, to appeal for help? Can one even be sure that the one to disappear returns and forms one of the band? There is nothing to indicate it; and this was the essential point which a sterling observer was bound not to neglect. Were they not rather five chance Necrophori who, guided by the smell, without any previous understanding, hastened to the abandoned Mouse to exploit her on their own account? I incline to this opinion, the most likely of all in the absence of exact information.

Probability becomes certainty if we submit the case to the verification of experiment. The test with the brick already gives us some information. For six hours my three specimens exhausted themselves in efforts before they got to the length of removing their booty and placing it on practicable soil. In this long and heavy task helpful neighbours would have been anything but unwelcome. Four other Necrophori, buried here and there under a little sand, comrades and acquaintances, helpers of the day before, were occupying the same cage; and not one of those concerned thought of summoning them to give a.s.sistance. Despite their extreme embarra.s.sment, the owners of the Mouse accomplished their task to the end, without the least help, though this could have been so easily requisitioned.

Being three, one might say, they considered themselves sufficiently strong; they needed no one else to lend them a hand. The objection does not hold good. On many occasions and under conditions even more difficult than those presented by a stony soil, I have again and again seen isolated Necrophori exhausting themselves in striving against my artifices; yet not once did they leave their work to recruit helpers.

Collaborators, it is true, did often arrive, but they were convoked by their sense of smell, not by the first possessor. They were fortuitous helpers; they were never called in. They were welcomed without disagreement, but also without grat.i.tude. They were not summoned; they were tolerated. In the glazed shelter where I keep the cage I happened to catch one of these chance a.s.sistants in the act. Pa.s.sing that way in the night and scenting dead flesh, he had entered where none of his kind had yet penetrated of his own free will. I surprised him on the wire-gauze dome of the cover. If the wire had not prevented him, he would have set to work incontinently, in company with the rest. Had my captives invited him? a.s.suredly not. He had hastened thither attracted by the odour of the Mole, heedless of the efforts of others. So it was with those whose obliging a.s.sistance is extolled. I repeat, in respect of their imaginary prowess, what I have said elsewhere of that of the Sacred Beetles: the story is a childish one, worthy of ranking with any fairy-tale written for the amus.e.m.e.nt of the simple.

A hard soil, necessitating the removal of the body, is not the only difficulty familiar to the Necrophori. Often, perhaps more often than not, the ground is covered with gra.s.s, above all with couch-gra.s.s, whose tenacious rootlets form an inextricable network below the surface. To dig in the interstices is possible, but to drag the dead animal through them is another matter: the meshes of the net are too close to give it pa.s.sage. Will the grave-digger find himself reduced to impotence by such an impediment, which must be an extremely common one?

That could not be.

Exposed to this or that habitual obstacle in the exercise of his calling, the animal is always equipped accordingly; otherwise his profession would be impracticable. No end is attained without the necessary means and apt.i.tudes. Besides that of the excavator, the Necrophorus certainly possesses another art: the art of breaking the cables, the roots, the stolons, the slender rhizomes which check the body's descent into the grave. To the work of the shovel and the pick must be added that of the shears. All this is perfectly logical and may be foreseen with complete lucidity. Nevertheless, let us invoke experiment, the best of witnesses.

I borrow from the kitchen-range an iron trivet whose legs will supply a solid foundation for the engine which I am devising. This is a coa.r.s.e network of strips of raphia, a fairly accurate imitation of the network of couch-gra.s.s roots. The very irregular meshes are nowhere wide enough to admit of the pa.s.sage of the creature to be buried, which in this case is a Mole. The trivet is planted with its three feet in the soil of the cage; its top is level with the surface of the soil. A little sand conceals the meshes. The Mole is placed in the centre; and my squad of s.e.xtons is let loose upon the body.

Without a hitch the burial is accomplished in the course of an afternoon. The hammock of raphia, almost equivalent to the natural network of couch-gra.s.s turf, scarcely disturbs the process of inhumation. Matters do not go forward quite so quickly; and that is all. No attempt is made to s.h.i.+ft the Mole, who sinks into the ground where he lies. The operation completed, I remove the trivet. The network is broken at the spot where the corpse lay. A few strips have been gnawed through; a small number, only so many as were strictly necessary to permit the pa.s.sage of the body.