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THE SISYPHUS BEETLE - THE INSTINCT OF PATERNITY




The duties of paternity are seldom imposed on any but the higher
animals. They are most notable in the bird; and the furry peoples acquit
themselves honourably. Lower in the scale we find in the father a
general indifference as to the fate of the family. Very few insects form
exceptions to this rule. Although all are imbued with a mating instinct
that is almost frenzied, nearly all, when the passion of the moment is
appeased, terminate then and there their domestic relations, and
withdraw, indifferent to the brood, which has to look after itself as
best it may.

This paternal coldness, which would be odious in the higher walks of
animal life, where the weakness of the young demands prolonged
assistance, has in the insect world the excuse that the new-born young
are comparatively robust, and are able, without help, to fill their
mouths and stomachs, provided they find themselves in propitious
surroundings. All that the prosperity of the race demands of the
Pierides, or Cabbage Butterflies, is that they should deposit their eggs
on the leaves of the cabbage; what purpose would be served by the
instincts of a father? The botanical instinct of the mother needs no
assistance. At the period of laying the father would be in the way. Let
him pursue his flirtations elsewhere; the laying of eggs is a serious
business.

In the case of the majority of insects the process of education is
unknown, or summary in the extreme. The insect has only to select a
grazing-ground upon which its family will establish itself the moment it
is hatched; or a site which will allow the young to find their proper
sustenance for themselves. There is no need of a father in these various
cases. After mating, the discarded male, who is henceforth useless,
drags out a lingering existence of a few days, and finally perishes
without having given the slightest assistance in the work of installing
his offspring.

But matters are not everywhere so primitive as this. There are tribes in
which an inheritance is prepared for the family which will assure it
both of food and of shelter in advance. The Hymenoptera in particular
are past-masters in the provision of cellars, jars, and other utensils
in which the honey-paste destined for the young is stored; they are
perfect in the art of excavating storehouses of food for their grubs.

This stupendous labour of construction and provisioning, this labour
that absorbs the insect's whole life, is the work of the mother only,
who wears herself out at her task. The father, intoxicated with
sunlight, lies idle on the threshold of the workshop, watching the
heroic female at her work, and regards himself as excused from all
labour when he has plagued his neighbours a little.

Does he never perform useful work? Why does he not follow the example
of the swallows, each of whom brings a fair share of the straw and
mortar for the building of the nest and the midges for the young brood?
No, he does nothing; perhaps alleging the excuse of his relative
weakness. But this is a poor excuse; for to cut out little circles from
a leaf, to rake a little cotton from a downy plant, or to gather a
little mortar from a muddy spot, would hardly be a task beyond his
powers. He might very well collaborate, at least as labourer; he could
at least gather together the materials for the more intelligent mother
to place in position. The true motive of his idleness is ineptitude.

It is a curious thing that the Hymenoptera, the most skilful of all
industrial insects, know nothing of paternal labour. The male of the
genus, in whom we should expect the requirements of the young to develop
the highest aptitudes, is as useless as a butterfly, whose family costs
so little to establish. The actual distribution of instinct upsets our
most reasonable previsions.

It upsets our expectations so completely that we are surprised to find
in the dung-beetle the noble prerogative which is lacking in the bee
tribe. The mates of several species of dung-beetle keep house together
and know the worth of mutual labour. Consider the male and female
Geotrupes, which prepare together the patrimony of their larvae; in their
case the father assists his companion with the pressure of his robust
body in the manufacture of their balls of compressed nutriment. These
domestic habits are astonishing amidst the general isolation.

To this example, hitherto unique, my continual researches in this
direction permit me to-day to add three others which are fully as
interesting. All three are members of the corporation of dung-beetles. I
will relate their habits, but briefly, as in many respects their history
is the same as that of the Sacred Scarabaeus, the Spanish Copris, and
others.

The first example is the Sisyphus beetle (_Sisyphus Schaefferi_, Lin.),
the smallest and most industrious of our pill-makers. It has no equal in
lively agility, grotesque somersaults, and sudden tumbles down the
impossible paths or over the impracticable obstacles to which its
obstinacy is perpetually leading it. In allusion to these frantic
gymnastics Latreille has given the insect the name of Sisyphus, after
the celebrated inmate of the classic Hades. This unhappy spirit
underwent terrible exertions in his efforts to heave to the top of a
mountain an enormous rock, which always escaped him at the moment of
attaining the summit, and rolled back to the foot of the slope. Begin
again, poor Sisyphus, begin again, begin again always! Your torments
will never cease until the rock is firmly placed upon the summit of the
mountain.

I like this myth. It is, in a way, the history of many of us; not odious
scoundrels worthy of eternal torments, but worthy and laborious folk,
useful to their neighbours. One crime alone is theirs to expiate: the
crime of poverty. Half a century or more ago, for my own part, I left
many blood-stained tatters on the crags of the inhospitable mountain; I
sweated, strained every nerve, exhausted my veins, spent without
reckoning my reserves of energy, in order to carry upward and lodge in
a place of security that crushing burden, my daily bread; and hardly was
the load balanced but it once more slipped downwards, fell, and was
engulfed. Begin again, poor Sisyphus; begin again, until your burden,
falling for the last time, shall crush your head and set you free at
length.

The Sisyphus of the naturalists knows nothing of these tribulations.
Agile and lively, careless of slope or precipice, he trundles his load,
which is sometimes food for himself, sometimes for his offspring. He is
very rare hereabouts; I should never have succeeded in obtaining a
sufficient number of specimens for my purpose but for an assistant whom
I may opportunely present to the reader, for he will be mentioned again
in these recitals.

This is my son, little Paul, aged seven. An assiduous companion of the
chase, he knows better than any one of his age the secrets of the
Cigale, the Cricket, and especially of the dung-beetle, his great
delight. At a distance of twenty yards his clear sight distinguishes the
refuse-tip of a beetle's burrow from a chance lump of earth; his fine
ear will catch the chirping of a grasshopper inaudible to me. He lends
me his sight and hearing, and I in return make him free of my thoughts,
which he welcomes attentively, raising his wide blue eyes questioningly
to mine.

What an adorable thing is the first blossoming of the intellect! Best of
all ages is that when the candid curiosity awakens and commences to
acquire knowledge of every kind. Little Paul has his own insectorium, in
which the Scarabaeus makes his balls; his garden, the size of a
handkerchief, in which he grows haricot beans, which are often dug up to
see if the little roots are growing longer; his plantation, containing
four oak-trees an inch in height, to which the acorns still adhere.
These serve as diversions after the arid study of grammar, which goes
forward none the worse on that account.

What beautiful and useful knowledge the teaching of natural history
might put into childish heads, if only science would consider the very
young; if our barracks of universities would only combine the lifeless
study of books with the living study of the fields; if only the red tape
of the curriculum, so dear to bureaucrats, would not strangle all
willing initiative. Little Paul and I will study as much as possible in
the open country, among the rosemary bushes and arbutus. There we shall
gain vigour of body and of mind; we shall find the true and the
beautiful better than in school-books.

To-day the blackboard has a rest; it is a holiday. We rise early, in
view of the intended expedition; so early that we must set out fasting.
But no matter; when we are hungry we shall rest in the shade, and you
will find in my knapsack the usual viaticum--apples and a crust of
bread. The month of May is near; the Sisyphus should have appeared. Now
we must explore at the foot of the mountain, the scanty pastures through
which the herds have passed; we must break with our fingers, one by one,
the cakes of sheep-dung dried by the sun, but still retaining a spot of
moisture in the centre. There we shall find Sisyphus, cowering and
waiting until the evening for fresher pasturage.

Possessed of this secret, which I learned from previous fortuitous
discoveries, little Paul immediately becomes a master in the art of
dislodging the beetle. He shows such zeal, has such an instinct for
likely hiding-places, that after a brief search I am rich beyond my
ambitions. Behold me the owner of six couples of Sisyphus beetles: an
unheard-of number, which I had never hoped to obtain.

For their maintenance a wire-gauze cover suffices, with a bed of sand
and diet to their taste. They are very small, scarcely larger than a
cherry-stone. Their shape is extremely curious. The body is dumpy,
tapering to an acorn-shaped posterior; the legs are very long,
resembling those of the spider when outspread; the hinder legs are
disproportionately long and curved, being thus excellently adapted to
enlace and press the little pilule of dung.

Mating takes place towards the beginning of May, on the surface of the
soil, among the remains of the sheep-dung on which the beetles have been
feeding. Soon the moment for establishing the family arrives. With equal
zeal the two partners take part in the kneading, transport, and baking
of the food for their offspring. With the file-like forelegs a morsel of
convenient size is shaped from the piece of dung placed in the cage.
Father and mother manipulate the piece together, striking it blows with
their claws, compressing it, and shaping it into a ball about the size
of a big pea.

As in the case of the _Scarabaeus sacer_, the exact spherical form is
produced without the mechanical device of rolling the ball. Before it is
moved, even before it is cut loose from its point of support, the
fragment is modelled into the shape of a sphere. The beetle as geometer
is aware of the form best adapted to the long preservation of preserved
foods.

The ball is soon ready. It must now be forced to acquire, by means of a
vigorous rolling, the crust which will protect the interior from a too
rapid evaporation. The mother, recognisable by her slightly robuster
body, takes the place of honour in front. Her long hinder legs on the
soil, her forelegs on the ball, she drags it towards her as she walks
backwards. The father pushes behind, moving tail first, his head held
low. This is exactly the method of the Scarabaeus beetles, which also
work in couples, though for another object. The Sisyphus beetles harness
themselves to provide an inheritance for their larvae; the larger insects
are concerned in obtaining the material for a banquet which the two
chance-met partners will consume underground.

The couple set off, with no definite goal ahead, across the
irregularities of the soil, which cannot be avoided by a leader who
hauls backwards. But even if the Sisyphus saw the obstacles she would
not try to evade them: witness her obstinate endeavour to drag her load
up the wire gauze of her cage!

A hopeless undertaking! Fixing her hinder claws in the meshes of the
wire gauze the mother drags her burden towards her; then, enlacing it
with her legs, she holds it suspended. The father, finding no purchase
for his legs, clutches the ball, grows on to it, so to speak, thus
adding his weight to that of the burden, and awaits events. The effort
is too great to last. Ball and beetle fall together. The mother, from
above, gazes a moment in surprise, and suddenly lets herself fall, only
to re-embrace the ball and recommence her impracticable efforts to scale
the wall. After many tumbles the attempt is at last abandoned.

Even on level ground the task is not without its difficulties. At every
moment the load swerves on the summit of a pebble, a fragment of gravel;
the team are overturned, and lie on their backs, kicking their legs in
the air. This is a mere nothing. They pick themselves up and resume
their positions, always quick and lively. The accidents which so often
throw them on their backs seem to cause them no concern; one would even
think they were invited. The pilule has to be matured, given a proper
consistency. In these conditions falls, shocks, blows, and jolts might
well enter into the programme. This mad trundling lasts for hours and
hours.

Finally, the mother, considering that the matter has been brought to a
satisfactory conclusion, departs in search of a favourable place for
storage. The father, crouched upon the treasure, waits. If the absence
of his companion is prolonged he amuses himself by rapidly whirling the
pill between his hind legs, which are raised in the air. He juggles with
the precious burden; he tests its perfections between his curved legs,
calliper-wise. Seeing him frisking in this joyful occupation, who can
doubt that he experiences all the satisfactions of a father assured of
the future of his family? It is I, he seems to say, it is I who have
made this loaf, so beautifully round; it is I who have made the hard
crust to preserve the soft dough; it is I who have baked it for my sons!
And he raises on high, in the sight of all, this magnificent testimonial
of his labours.

But now the mother has chosen the site. A shallow pit is made, the mere
commencement of the projected burrow. The ball is pushed and pulled
until it is close at hand. The father, a vigilant watchman, still
retains his hold, while the mother digs with claws and head. Soon the
pit is deep enough to receive the ball; she cannot dispense with the
close contact of the sacred object; she must feel it bobbing behind her,
against her back, safe from all parasites and robbers, before she can
decide to burrow further. She fears what might happen to the precious
loaf if it were abandoned at the threshold of the burrow until the
completion of the dwelling. There is no lack of midges and tiny
dung-beetles--Aphodiinae--which might take possession of it. It is only
prudent to be distrustful.

So the ball is introduced into the pit, half in and half out of the
mouth of the burrow. The mother, below, clasps and pulls; the father,
above, moderates the jolts and prevents it from rolling. All goes well.
Digging is resumed, and the descent continues, always with the same
prudence; one beetle dragging the load, the other regulating its descent
and clearing away all rubbish that might hinder the operation. A few
more efforts, and the ball disappears underground with the two miners.
What follows will be, for a time at least, only a repetition of what we
have seen. Let us wait half a day or so.

If our vigilance is not relaxed we shall see the father regain the
surface alone, and crouch in the sand near the mouth of the burrow.
Retained by duties in the performance of which her companion can be of
no assistance, the mother habitually delays her reappearance until the
following day. When she finally emerges the father wakes up, leaves his
hiding place, and rejoins her. The reunited couple return to their
pasturage, refresh themselves, and then cut out another ball of dung.
As before, both share the work; the hewing and shaping, the transport,
and the burial in ensilage.

This conjugal fidelity is delightful; but is it really the rule? I
should not dare to affirm that it is. There must be flighty individuals
who, in the confusion under a large cake of droppings, forget the fair
confectioners for whom they have worked as journeymen, and devote
themselves to the services of others, encountered by chance; there must
be temporary unions, and divorces after the burial of a single pellet.
No matter: the little I myself have seen gives me a high opinion of the
domestic morals of the Sisyphus.

Let us consider these domestic habits a little further before coming to
the contents of the burrow. The father works fully as hard as the mother
at the extraction and modelling of the pellet which is destined to be
the inheritance of a larva; he shares in the work of transport, even if
he plays a secondary part; he watches over the pellet when the mother is
absent, seeking for a suitable site for the excavation of the cellar; he
helps in the work of digging; he carries away the rubbish from the
burrow; finally, to crown all these qualities, he is in a great measure
faithful to his spouse.

The Scarabaeus exhibits some of these characteristics. He also assists
his spouse in the preparation of pellets of dung; he also assists her to
transport the pellets, the pair facing each other and the female going
backwards. But as I have stated already, the motive of this mutual
service is selfish; the two partners labour only for their own good. The
feast is for themselves alone. In the labours that concern the family
the female Scarabaeus receives no assistance. Alone she moulds her
sphere, extracts it from the lump and rolls it backwards, with her back
to her task, in the position adopted by the male Sisyphus; alone she
excavates her burrow, and alone she buries the fruit of her labour.
Oblivious of the gravid mother and the future brood, the male gives her
no assistance in her exhausting task. How different to the little
pellet-maker, the Sisyphus!

It is now time to visit the burrow. At no very great depth we find a
narrow chamber, just large enough for the mother to move around at her
work. Its very exiguity proves that the male cannot remain underground;
so soon as the chamber is ready he must retire in order to leave the
female room to move. We have, in fact, seen that he returns to the
surface long before the female.

The contents of the cellar consist of a single pellet, a masterpiece of
plastic art. It is a miniature reproduction of the pear-shaped ball of
the Scarabaeus, a reproduction whose very smallness gives an added value
to the polish of the surface and the beauty of its curves. Its larger
diameter varies from half to three-quarters of an inch. It is the most
elegant product of the dung-beetle's art.

But this perfection is of brief duration. Very soon the little "pear"
becomes covered with gnarled excrescences, black and twisted, which
disfigure it like so many warts. Part of the surface, which is otherwise
intact, disappears under a shapeless mass. The origin of these knotted
excrescences completely deceived me at first. I suspected some
cryptogamic vegetation, some _Spheriaecaea_, for example, recognisable by
its black, knotted, incrusted growth. It was the larva that showed me my
mistake.

The larva is a maggot curved like a hook, carrying on its back an ample
pouch or hunch, forming part of its alimentary canal. The reserve of
excreta in this hunch enables it to seal accidental perforations of the
shell of its lodging with an instantaneous jet of mortar. These sudden
emissions, like little worm-casts, are also practised by the Scarabaeus,
but the latter rarely makes use of them.

The larvae of the various dung-beetles utilise their alimentary residues
in rough-casting their houses, which by their dimensions lend themselves
to this method of disposal, while evading the necessity of opening
temporary windows by which the ordure can be expelled. Whether for lack
of sufficient room, or for other reasons which escape me, the larva of
the Sisyphus, having employed a certain amount in the smoothing of the
interior, ejects the rest of its digestive products from its dwelling.

Let us examine one of these "pears" when the inmate is already partly
grown. Sooner or later we shall see a spot of moisture appear at some
point on the surface; the wall softens, becomes thinner, and then,
through the softened shell, a jet of dark green excreta rises and falls
back upon itself in corkscrew convolutions. One excrescence the more has
been formed; as it dries it becomes black.

What has occurred? The larva has opened a temporary breach in the wall
of its shell; and through this orifice, in which a slight thickness of
the outer glaze still remains, it has expelled the excess of mortar
which it could not employ within. This practice of forming oubliettes in
the shell of its prison does not endanger the grub, as they are
immediately closed, and hermetically sealed by the base of the jet,
which is compressed as by a stroke of a trowel. The stopper is so
quickly put in place that the contents remain moist in spite of the
frequent breaches made in the shell of the "pear." There is no danger of
an influx of the dry outer air.

The Sisyphus seems to be aware of the peril which later on, in the
dog-days, will threaten its "pear," small as it is, and so near the
surface of the ground. It is extremely precocious. It labours in April
and May when the air is mild. In the first fortnight of July, before the
terrible dog-days have arrived, the members of its family break their
shells and set forth in search of the heap of droppings which will
furnish them with food and lodging during the fierce days of summer.
Then come the short but pleasant days of autumn, the retreat underground
and the winter torpor, the awakening of spring, and finally the cycle is
closed by the festival of pellet-making.

One word more as to the fertility of the Sisyphus. My six couples under
the wire-gauze cover furnished me with fifty-seven inhabited pellets.
This gives an average of more than nine to each couple; a figure which
the _Scarabaeus sacer_ is far from attaining. To what should we attribute
this superior fertility? I can only see one cause: the fact that the
male works as valiantly as the female. Family cares too great for the
strength of one are not too heavy when there are two to support them.





Next: A BEE-HUNTER - THE PHILANTHUS AVIPORUS

Previous: THE ITALIAN CRICKET



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