Chapter V. The Burying Beetle: The Burying
Jean-Henri Fabre The Wonders of Instinct
Burying beetle (Nicrophorus vespillo)
Beside the footpath in April lies the Mole, disembowelled by the peasant's spade; at the foot of the hedge the pitiless urchin has stoned to death the Lizard, who was about to don his green, pearl-embellished costume. The passer-by has thought it a meritorious deed to crush beneath his heel the chance-met Adder; and a gust of wind has thrown a tiny unfeathered bird from its nest. What will become of these little bodies and of so many other pitiful remnants of life? They will not long offend our sense of sight and smell. The sanitary officers of the fields are legion.
An eager freebooter, ready for any task, the Ant is the first to come hastening and begin, particle by particle, to dissect the corpse. Soon the odour of the corpse attracts the Fly, the genitrix of the odious maggot. At the same time, the flattened Silpha, the glistening, slow-trotting Horn-beetle, the Dermestes, powdered with snow upon the abdomen, and the slender Staphylinus, all, whence coming no one knows, hurry hither in squads, with never-wearied zeal, investigating, probing and draining the infection.
What a spectacle, in the spring, beneath a dead Mole! The horror of this laboratory is a beautiful sight for one who is able to observe and to meditate. Let us overcome our disgust; let us turn over the unclean refuse with our foot. What a swarming there is beneath it, what a tumult of busy workers! The Silphae, with wing-cases wide and dark, as though in mourning, fly distraught, hiding in the cracks in the soil; the Saprini, of polished ebony which mirrors the sunlight, jog hastily off, deserting their workshop; the Dermestes, of whom one wears a fawn-coloured tippet, spotted with white, seek to fly away, but, tipsy with their putrid nectar, tumble over and reveal the immaculate whiteness of their bellies, which forms a violent contrast with the gloom of the rest of their attire.
What were they doing there, all these feverish workers? They were making a clearance of death on behalf of life. Transcendent alchemists, they were transforming that horrible putridity into a living and inoffensive product. They were draining the dangerous corpse to the point of rendering it as dry and sonorous as the remains of an old slipper hardened on the refuse-heap by the frosts of winter and the heats of summer. They were working their hardest to render the carrion innocuous.
Others will soon put in their appearance, smaller creatures and more patient, who will take over the relic and exploit it ligament by ligament, bone by bone, hair by hair, until the whole has been resumed by the treasury of life. All honour to these purifiers! Let us put back the Mole and go our way.
Some other victim of the agricultural labours of spring--a Shrew-mouse, Field-mouse, Mole, Frog, Adder, or Lizard--will provide us with the most vigorous and famous of these expurgators of the soil. This is the Burying-beetle, the Necrophorus, so different from the cadaveric mob in dress and habits. In honour of his exalted functions he exhales an odour of musk; he bears a red tuft at the tip of his antennae; his breast is covered with nankeen; and across his wing-cases he wears a double, scalloped scarf of vermilion. An elegant, almost sumptuous costume, very superior to that of the others, but yet lugubrious, as befits your undertaker's man.
He is no anatomical dissector, cutting his subject open, carving its flesh with the scalpel of his mandibles; he is literally a gravedigger, a sexton. While the others--Silphae, Dermestes, Horn-beetles--gorge themselves with the exploited flesh, without, of course, forgetting the interests of the family, he, a frugal eater, hardly touches his booty on his own account. He buries it entire, on the spot, in a cellar where the thing, duly ripened, will form the diet of his larvae. He buries it in order to establish his progeny therein.
This hoarder of dead bodies, with his stiff and almost heavy movements, is astonishingly quick at storing away wreckage. In a shift of a few hours, a comparatively enormous animal--a Mole, for example--disappears, engulfed by the earth. The others leave the dried, emptied carcass to the air, the sport of the winds for months on end; he, treating it as a whole, makes a clean job of things at once. No visible trace of his work remains but a tiny hillock, a burial-mound, a tumulus.
With his expeditious method, the Necrophorus is the first of the little purifiers of the fields. He is also one of the most celebrated of insects in respect of his psychical capacities. This undertaker is endowed, they say, with intellectual faculties approaching to reason, such as are not possessed by the most gifted of the Bees and Wasps, the collectors of honey or game. He is honoured by the two following anecdotes, which I quote from Lacordaire's „Introduction to Entomology,“ the only general treatise at my disposal:
„Clairville,“ says the author, „records that he saw a Necrophorus vespillo, who, wishing to bury a dead Mouse and finding the soil on which the body lay too hard, proceeded to dig a hole at some distance in soil more easily displaced. This operation completed, he attempted to bury the Mouse in this cavity, but, not succeeding, he flew away, returning a few moments later accompanied by four of his fellows, who assisted him to move the Mouse and bury it.“
In such actions, Lacordaire adds, we cannot refuse to admit the intervention of reason.
„The following case,“ he continues, „recorded by Gledditsch, has also every indication of the intervention of reason. One of his friends, wishing to desiccate a Frog, placed it on the top of a stick thrust into the ground, in order to make sure that the Necrophori should not come and carry it off. But this precaution was of no effect; the insects, being unable to reach the Frog, dug under the stick and, having caused it to fall, buried it as well as the body.“ („Suites a Buffon. Introduction a l'entomologie“ volume 2 pages 460–61.--Author's Note.)
To grant, in the intellect of the insect, a lucid understanding of the relations between cause and effect, between the end and the means, is an affirmation of serious import. I know of scarcely any better adapted to the philosophical brutalities of my time. But are these two little stories really true? Do they involve the consequences deduced from them? Are not those who accept them as reliable testimony a little over-simple?
To be sure, simplicity is needed in entomology. Without a good dose of this quality, a mental defect in the eyes of practical folk, who would busy himself with the lesser creatures? Yes, let us be simple, without being childishly credulous. Before making insects reason, let us reason a little ourselves; let us, above all, consult the experimental test. A fact gathered at hazard, without criticism, cannot establish a law.
I do not propose, O valiant grave-diggers, to belittle your merits; such is far from being my intention. I have that in my notes, on the other hand, which will do you more honour than the case of the gibbet and the Frog; I have gleaned, for your benefit, examples of prowess which will shed a new lustre upon your reputation.
No, my intention is not to lessen your renown. However, it is not the business of impartial history to maintain a given thesis; it follows whither the facts lead it. I wish simply to question you upon the power of logic attributed to you. Do you or do you not enjoy gleams of reason? Have you within you the humble germ of human thought? That is the problem before us.
To solve it we will not rely upon the accidents which good fortune may now and again procure for us. We must employ the breeding-cage, which will permit of assiduous visits, continued inquiry and a variety of artifices. But how populate the cage? The land of the olive-tree is not rich in Necrophori. To my knowledge it possesses only a single species, N. vestigator (Hersch.); and even this rival of the grave-diggers of the north is pretty scarce. The discovery of three or four in the course of the spring was as much as my searches yielded in the old days. This time, if I do not resort to the ruses of the trapper, I shall obtain them in no greater numbers; whereas I stand in need of at least a dozen.
These ruses are very simple. To go in search of the layer-out of bodies, who exists only here and there in the country-side, would be almost always waste of time; the favourable month, April, would elapse before my cage was suitably populated. To run after him is to trust too much to accident; so we will make him come to us by scattering in the orchard an abundant collection of dead Moles. To this carrion, ripened by the sun, the insect will not fail to hasten from the various points of the horizon, so accomplished is he in the detection of such a delicacy.
I make an arrangement with a gardener in the neighbourhood, who, two or three times a week, supplements the penury of my acre and a half of stony ground, providing me with vegetables raised in a better soil. I explain to him my urgent need of Moles, an indefinite number of moles. Battling daily with trap and spade against the importunate excavator who uproots his crops, he is in a better position than any one else to procure for me that which I regard for the moment as more precious than his bunches of asparagus or his white-heart cabbages.
The worthy man at first laughs at my request, being greatly surprised by the importance which I attribute to the abhorrent creature, the Darboun; but at last he consents, not without a suspicion at the back of his mind that I am going to make myself a wonderful flannel-lined waist-coat with the soft, velvety skins of the Moles, something good for pains in the back. Very well. We settle the matter. The essential thing is that the Darbouns shall reach me.
They reach me punctually, by twos, by threes, by fours, packed in a few cabbage-leaves, at the bottom of the gardener's basket. The worthy man who lent himself with such good grace to my strange requirements will never guess how much comparative psychology will owe him! In a few days I was the possessor of thirty Moles, which were scattered here and there, as they reached me, in bare portions of the orchard, amid the rosemary-bushes, the arbutus-trees, and the lavender-beds.
Now it only remained to wait and to examine, several times a day, the under-side of my little corpses, a disgusting task which any one would avoid who had not the sacred fire in his veins. Only little Paul, of all the household, lent me the aid of his nimble hand to seize the fugitives. I have already stated that the entomologist has need of simplicity of mind. In this important business of the Necrophori, my assistants were a child and an illiterate.
Little Paul's visits alternating with mine, we had not long to wait. The four winds of heaven bore forth in all directions the odour of the carrion; and the undertakers hurried up, so that the experiments, begun with four subjects, were continued with fourteen, a number not attained during the whole of my previous searches, which were unpremeditated and in which no bait was used as decoy. My trapper's ruse was completely successful.
Before I report the results obtained in the cage, let us for a moment stop to consider the normal conditions of the labours that fall to the lot of the Necrophori. The Beetle does not select his head of game, choosing one in proportion to his strength, as do the predatory Wasps; he accepts it as hazard presents it to him. Among his finds there are little creatures, such as the Shrew-mouse; animals of medium size, such as the Field-mouse; and enormous beasts, such as the Mole, the Sewer-rat and the Snake, any of which exceeds the powers of excavation of a single grave-digger. In the majority of cases transportation is impossible, so disproportioned is the burden to the motive-power. A slight displacement, caused by the effort of the insects' backs, is all that can possibly be effected.
Ammophilus and Cerceris, Sphex and Pompilus excavate their burrows wherever they please; they carry their prey thither on the wing, or, if too heavy, drag it afoot. The Necrophorus knows no such facilities in his task. Incapable of carrying the monstrous corpse, no matter where encountered, he is forced to dig the grave where the body lies.
This obligatory place of sepulture may be in stony soil; it may occupy this or that bare spot, or some other where the grass, especially the couch-grass, plunges into the ground its inextricable network of little cords. There is a great probability, too, that a bristle of stunted brambles may support the body at some inches from the soil. Slung by the labourers' spade, which has just broken his back, the Mole falls here, there, anywhere, at random; and where the body falls, no matter what the obstacles--provided they be not insurmountable--there the undertaker must utilize it.
The difficulties of inhumation are capable of such variety as causes us already to foresee that the Necrophorus cannot employ fixed methods in the accomplishment of his labours. Exposed to fortuitous hazards, he must be able to modify his tactics within the limits of his modest perceptions. To saw, to break, to disentangle, to lift, to shake, to displace: these are so many methods of procedure which are indispensable to the grave-digger in a predicament. Deprived of these resources, reduced to uniformity of method, the insect would be incapable of pursuing the calling which has fallen to its lot.
We see at once how imprudent it would be to draw conclusions from an isolated case in which rational coordination or premeditated intention might appear to intervene. Every instinctive action no doubt has its motive; but does the animal in the first place judge whether the action is opportune? Let us begin by a careful consideration of the creature's labours; let us support each piece of evidence by others; and then we shall be able to answer the question.
First of all, a word as to diet. A general scavenger, the Burying-beetle refuses nothing in the way of cadaveric putridity. All is good to his senses, feathered game or furry, provided that the burden do not exceed his strength. He exploits the batrachian or the reptile with no less animation. he accepts without hesitation extraordinary finds, probably unknown to his race, as witness a certain Gold-fish, a red Chinese Carp, whose body, placed in one of my cages, was instantly considered an excellent tit-bit and buried according to the rules. Nor is butcher's meat despised. A mutton-cutlet, a strip of beefsteak, in the right stage of maturity, disappeared beneath the soil, receiving the same attention as those which were lavished on the Mole or the Mouse. In short, the Necrophorus has no exclusive preferences; anything putrid he conveys underground.
The maintenance of his industry, therefore, presents no sort of difficulty. If one kind of game be lacking, some other--the first to hand--will very well replace it. Neither is there much trouble in establishing the site of his industry. A capacious dish-cover of wire gauze is sufficient, resting on an earthen pan filled to the brim with fresh, heaped sand. To obviate criminal attempts on the part of the Cats, whom the game would not fail to tempt, the cage is installed in a closed room with glazed windows, which in winter is the refuge of the plants and in summer an entomological laboratory.
Now to work. The Mole lies in the centre of the enclosure. The soil, easily shifted and homogeneous, realizes the best conditions for comfortable work. Four Necrophori, three males and a female, are there with the body. They remain invisible, hidden beneath the carcass, which from time to time seems to return to life, shaken from end to end by the backs of the workers. An observer not in the secret would be somewhat astonished to see the dead creature move. From time to time, one of the sextons, almost always a male, emerges and goes the rounds of the animal, which he explores, probing its velvet coat. He hurriedly returns, appears again, once more investigates and creeps back under the corpse.
The tremors become more pronounced; the carcass oscillates, while a cushion of sand, pushed outward from below, grows up all about it. The Mole, by reason of his own weight and the efforts of the grave-diggers, who are labouring at their task beneath him, gradually sinks, for lack of support, into the undermined soil.
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 sextons, 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 pass when passage 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 assist me.
The Mole is a Mole no longer, but a greenish horror, putrid, hairless, shrunk into a round, greasy mass. 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 tit-bit lies in a spacious 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 assistance, 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 partnership, 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, assuredly, of the brood, are also stirring amid the infected mass. 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 shiny 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 sextons 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 Massagetae and others, used to kill their aged folk in order to spare them the miseries of senility. The fatal blow on the hoary 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 Massagetae 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.