Informational Site NetworkInformational Site Network
Privacy
 
   Home - Articles - Books

THE PROBLEM OF THE SCOLIAE




Now that all the facts have been set forth, it is time to collate them. We
already know that the Beetle-hunters, the Cerceres (Cf. "The Hunting
Wasps": chapters 1 to 3.--Translator's Note.), prey exclusively on the
Weevils and the Buprestes, that is, on the families whose nervous system
presents a degree of concentration which may be compared with that of the
Scolia's victims. Those predatory insects, working in the open air, are
exempt from the difficulties which their emulators, working underground,
have to overcome. Their movements are free and are directed by the sense of
sight; but their surgery is confronted in another respect with a most
arduous problem.

The victim, a Beetle, is covered at all points with a suit of armour which
the sting is unable to penetrate. The joints alone will allow the poisoned
lancet to pass. Those of the legs do not in any way comply with the
conditions imposed: the result of stinging them would be merely a partial
disorder which far from subduing the insect, would render it more dangerous
by irritating it yet further. A sting in the joint of the neck is not
admissible: it would injure the cervical ganglia and lead to death,
followed by putrefaction. There remains only the joint between the corselet
and the abdomen.

The sting, in entering here, has to abolish all movement with a single
stab, for any movement would imperil the rearing of the larva. The success
of the paralysis, therefore, demands that the motor ganglia, at least the
three thoracic ganglia, shall be packed in close contact opposite this
point. This determines the selection of Weevils and Buprestes, both of
which are so strongly armoured.

But where the prey has only a soft skin, incapable of stopping the sting,
the concentrated nervous system is no longer necessary, for the operator,
versed in the anatomical secrets of her victim, knows to perfection where
the centres of innervation lie; and she wounds them one after another, if
need be from the first to the last. Thus do the Ammophilae go to work when
dealing with their caterpillars and the Sphex-wasps when dealing with their
Locusts, Ephippigers and Crickets.

With the Scoliae we come once again to a soft prey, with a skin penetrable
by the sting no matter where it be attacked. Will the tactics of the
caterpillar-hunters, who stab and stab again, be repeated here? No, for the
difficulty of movement under ground prohibits so complicated an operation.
Only the tactics of the paralysers of armour-clad insects are practicable
now, for, since there is but one thrust of the dagger, the feat of surgery
is reduced to its simplest terms, a necessary consequence of the
difficulties of an underground operation. The Scoliae, then, whose destiny
it is to hunt and paralyse under the soil the victuals for their family,
require a prey made highly vulnerable by the close assemblage of the nerve-
centres, as are the Weevils and Buprestes of the Cerceres; and this is why
it has fallen to their lot to share among them the larvae of the
Scarabaeidae.

Before they obtained their allotted portion, so closely restricted and so
judiciously selected; before they discovered the precise and almost
mathematical point at which the sting must enter to produce a sudden and a
lasting immobility; before they learnt how to consume, without incurring
the risk of putrefaction, so corpulent a prey: in brief, before they
combined these three conditions of success, what did the Scoliae do?

The Darwinian school will reply that they were hesitating, essaying,
experimenting. A long series of blind gropings eventually hit upon the most
favourable combination, a combination henceforth to be perpetuated by
hereditary transmission. The skilful co-ordination between the end and the
means was originally the result of an accident.

Chance! A convenient refuge! I shrug my shoulders when I hear it invoked to
explain the genesis of an instinct so complex as that of the Scoliae. In
the beginning, you say, the creature gropes and feels its way; there is
nothing settled about its preferences. To feed its carnivorous larvae it
levies tribute on every species of game which is not too much for the
huntress' power or the nurseling's appetite; its descendants try now this,
now that, now something else, at random, until the accumulated centuries
lead to the selection which best suits the race. Then habit grows fixed and
becomes instinct.

Very well. Let us agree that the Scolia of antiquity sought a different
prey from that adopted by the modern huntress. If the family throve upon a
diet now discontinued, we fail to see that the descendants had any reason
to change it: animals have not the gastronomic fancies of an epicure whom
satiety makes difficult to please. Because the race did well upon this
fare, it became habitual; and instinct became differently fixed from what
it is to-day. If, on the other hand, the original food was unsuitable, the
existence of the family was jeopardized; and any attempt at future
improvement became impossible, because an unhappily inspired mother would
leave no heirs.

To escape falling into this twofold trap, the theorists will reply that the
Scoliae are descended from a precursor, an indeterminate creature, of
changeable habits and changing form, modifying itself in accordance with
its environment and with the regional and climatic conditions and branching
out into races each of which has become a species with the attributes which
distinguish it to-day. The precursor is the deus ex machina of evolution.
When the difficulty becomes altogether too importunate, quick, a precursor,
to fill up the gaps, quick, an imaginary creature, the nebulous plaything
of the mind! This is seeking to lighten the darkness with a still deeper
obscurity; to illumine the day by piling cloud upon cloud. Precursors are
easier to find than sound arguments. Nevertheless, let us put the precursor
of the Scoliae to the test.

What did she do? Being capable of everything, she did a bit of everything.
Among its descendants were innovators who developed a taste for tunnelling
in sand and vegetable mould. There they encountered the larvae of the
Cetonia, the Oryctes, the Anoxia, succulent morsels on which to rear their
families. By degrees the indeterminate Wasp adopted the sturdy proportions
demanded by underground labour. By degrees she learnt to stab her plump
neighbours in scientific fashion; by degrees she acquired the difficult art
of consuming her prey without killing it; at length, by degrees, aided by
the richness of her diet, she became the powerful Scolia with whom we are
familiar. Having reached this point, the species assumes a permanent form,
as does its instinct.

Here we have a multiplicity of stages, all of the slowest, all of the most
incredible nature, whereas the Wasp cannot found a race except on the
express condition of complete success from the first attempt. We will not
insist further upon the insurmountable objection; we will admit that, amid
so many unfavourable chances, a few favoured individuals survive, becoming
more and more numerous from one generation to the next, in proportion as
the dangerous art of rearing the young is perfected. Slight variations in
one and the same direction form a definite whole; and at long last the
ancient precursor has become the Scolia of our own times.

By the aid of a vague phraseology which juggles with the secret of the
centuries and the unknown things of life, it is easy to build up a theory
in which our mental sloth delights, after being discouraged by difficult
researches whose final result is doubt rather than positive statement. But
if, so far from being satisfied with hazy generalities and adopting as
current coin the terms consecrated by fashion, we have the perseverance to
explore the truth as far as lies in our power, the aspect of things will
undergo a great change and we shall discover that they are far less simple
than our overprecipitate views declared them to be. Generalization is
certainly a most valuable instrument: science indeed exists only by virtue
of it. Let us none the less beware of generalizations which are not based
upon very firm and manifold foundations.

When these foundations are lacking, the child is the great generalizer. For
him, the feathered world consists merely of birds; the race of reptiles
merely of snakes, the only difference being that some are big and some are
little. Knowing nothing, he generalizes in the highest degree; he
simplifies, in his inability to perceive the complex. Later he will learn
that the Sparrow is not the Bullfinch, that the Linnet is not the
Greenfinch; he will particularize and to a greater degree each day, as his
faculty of observation becomes more fully trained. In the beginning he saw
nothing but resemblances; he now sees differences, but still not plainly
enough to avoid incongruous comparisons.

In his adult years he will almost to a certainty commit zoological blunders
similar to those which my gardener retails to me. Favier, an old soldier,
has never opened a book, for the best of reasons. He barely knows how to
cipher: arithmetic rather than reading is forced upon us by the brutalities
of life. Having followed the flag over three-quarters of the globe, he has
an open mind and a memory crammed with reminiscences, which does not
prevent him, when we chat about animals, from making the most crazy
assertions. For him the Bat is a Rat that has grown wings; the Cuckoo is a
Sparrow-hawk retired from business; the Slug is a Snail who has lost his
shell with the advance of years; the Nightjar (Known also as the
Goatsucker, because of the mistaken belief that the bird sucks the milk of
Goats, and, in America, as the Whippoorwill.--Translator's Note.), the
Chaoucho-grapaou, as he calls her, is an elderly Toad, who, becoming
enamoured of milk-food, has grown feathers, so that she may enter the byres
and milk the Goats. It is impossible to drive these fantastic ideas out of
his head. Favier himself, as will be seen, is an evolutionist after his own
fashion, an evolutionist of a very daring type. In accounting for the
origin of animals nothing gives him pause. He has a reply to everything:
"this" comes from "that." If you ask him why, he answers:

"Look at the resemblance!"

Shall we reproach him with these insanities, when we hear another, misled
by the Monkey's build, acclaim the Pithecanthropus as man's precursor?
Shall we reject the metamorphosis of the Chaoucho-grapaou, when people tell
us in all seriousness that, in the present stage of scientific knowledge,
it is absolutely proved that man is descended from some rough-hewn Ape? Of
the two transformations, Favier's strikes me as the more credible. A
painter of my acquaintance, a brother of the great composer Felicien David
(Felicien Cesar David (1810-1876). His chief work was the choral symphony
"Le Desert":--Translator's Note.), favoured me one day with his reflections
on the human structure:

"Ve, moun bel ami," he said. "Ve, l'home a lou dintre d'un por et lou
defero d'uno mounino." "See, my dear friend, see: man has the inside of a
pig and the outside of a monkey."

I recommend the painter's aphorism to those who might like to discover
man's origin in the Hog when the Ape has gone out of fashion. According to
David, descent is proved by internal resemblances:

"L'home a lou dintre d'un por."

The inventory of precursory types sees nothing but organic resemblances and
disdains the differences of aptitude. By consulting only the bones, the
vertebrae, the hair, the nervures of the wings, the joints of the antennae,
the imagination may build up any sort of genealogical tree that will fit
with our theories of classification, for, when all is said, the animal, in
its widest generalization, is represented by a digestive tube. With this
common factor, the way lies open to every kind of error. A machine is
judged not by this or that train of wheels, but by the nature of the work
accomplished. The monumental roasting-jack of a waggoners' inn and a
Breguet chronometer both have trains of cogwheels geared in almost a
similar fashion. (Louis Breguet (1803-1883), a famous Parisian watchmaker
and physicist.--Translator's Note.) Are we to class the two mechanisms
together? Shall we forget that the one turns a shoulder of mutton before
the hearth, while the other divides time into seconds?

In the same way, the organic scaffolding is dominated from on high by the
aptitudes of the animal, especially that superior characteristic, the
psychical aptitudes. That the Chimpanzee and the hideous Gorilla possess
close resemblances of structure to our own is obvious. But let us for a
moment consider their aptitudes. What differences, what a dividing gulf!
Without exalting ourselves as high as the famous reed of which Pascal
speaks, that reed which, in its weakness, by the mere fact that it knows
itself to be crushed, is superior to the world that crushes it, we may at
least ask to be shown, somewhere, an animal making an implement, which will
multiply its skill and its strength, or taking possession of fire, the
primordial element of progress. (Blaise Pascal(1623-1662). The allusion is
to a passage in the philosopher's "Pensees." Pascal describes man as a
reed, the weakest thing in nature, but "a thinking reed."--Translator's
Note.) Master of implements and of fire! These two aptitudes, simple though
they be, characterize man better than the number of his vertebrae and his
molars.

You tell us that man, at first a hairy brute, walking on all fours, has
risen on his hind-legs and shed his fur; and you complacently demonstrate
how the elimination of the hairy pelt was effected. Instead of bolstering
up a theory with a handful of fluff gained or lost, it would perhaps be
better to settle how the original brute became the possessor of implements
and fire. Aptitudes are more important than hair; and you neglect them
because it is there that the insurmountable difficulty really resides. See
how the great master of evolution hesitates and stammers when he tries, by
fair means or foul, to fit instinct into the mould of his formulae. It is
not so easy to handle as the colour of the pelt, the length of the tail,
the ear that droops or stands erect. Yes, our master well knows that this
is where the shoe pinches! Instinct escapes him and brings his theory
crumbling to the ground.

Let us return to what the Scoliae teach us on this question, which
incidentally touches on our own origin. In conformity with the Darwinian
ideas, we have accepted an unknown precursor, who by dint of repeated
experiment, adopted as the victuals to be hoarded the larvae of the
Scarabaeidae. This precursor, modified by varying circumstances, is
supposed to have subdivided herself into ramifications, one of which,
digging into vegetable mould and preferring the Cetonia to any other game
inhabiting the same heap, became the Two-banded Scolia; another, also
addicted to exploring the soil, but selecting the Oryctes, left as its
descendant the Garden Scolia; and a third, establishing itself in sandy
ground, where it found the Anoxia, was the ancestress of the Interrupted
Scolia. To these three ramifications we must beyond a doubt add others
which complete the series of the Scolia. As their habits are known to me
only by analogy, I confine myself to mentioning them.

The three species at least, therefore, with which I am familiar would
appear to be derived from a common precursor. To traverse the distance from
the starting-point to the goal, all three have had to contend with
difficulties, which are extremely grave if considered one by one and are
aggravated even more by this circumstance, that the overcoming of one would
lead to nothing unless the others were surmounted as successfully. Success,
then, is contingent upon a series of conditions, each one of which offers
almost no chance of victory, so that the fulfilment of them all becomes a
mathematical absurdity if we are to invoke accident alone.

And, in the first place, how was it that the Scolia of antiquity, having to
provide rations for her carnivorous family, adopted for her prey only those
larvae which, owing to the concentration of their nervous systems, form so
remarkable and so rare an exception in the insect order? What chance would
hazard offer her of obtaining this prey, the most suitable of all because
the most vulnerable? The chance represented by unity compared with the
indefinite number of entomological species. The odds are as one to
immensity.

Let us continue. The larva of the Scarabaeid is snapped up underground, for
the first time. The victim protests, defends itself after its fashion,
coils itself up and presents to the sting on every side a surface on which
a wound entails no serious danger. And yet the Wasp, an absolute novice,
has to select, for the thrust of its poisoned weapon, one single point,
narrowly restricted and hidden in the folds of the larva's body. If she
miscalculates, she may be killed: the larva, irritated by the smarting
puncture, is strong enough to disembowel her with the tusks of its
mandibles. If she escapes the danger, she will nevertheless perish without
leaving any offspring, since the necessary provisions will be lacking.
Salvation for herself and her race depends on this: whether at the first
thrust she is able to reach the little nervous plexus which measures barely
one-fiftieth of an inch in width. What chance has she of plunging her
lancet into it, if there is nothing to guide her? The chance represented by
unity compared with the number of points composing the victim's body. The
odds are as one against immensity.

Let us proceed still further. The sting has reached the mark; the fat grub
is deprived of movement. At what spots should the egg now be laid? In
front, behind, on the sides, the back or the belly? The choice is not a
matter of indifference. The young grub will pierce the skin of its
provender at the very spot on which the egg was fixed; and, once an opening
is made, it will go ahead without hesitation. If this point of attack is
ill-chosen, the nurseling runs the risk of presently finding under its
mandibles some essential organ, which should have been respected until the
end in order to keep the victuals fresh. Remember how difficult it is to
complete the rearing when the tiny larva is moved from the place chosen by
the mother. The game promptly becomes putrid and the Scolia dies.

It is impossible for me to state the precise motives which lead to the
adoption of the spot on which the egg is laid; I can perceive general
reasons, but the details escape me, as I am not well enough versed in the
more delicate questions of anatomy and entomological physiology. What I do
know with absolute certainty is that the same spot is invariably chosen for
laying the egg. With not a single exception, on all the victims extracted
from the heap of garden mould--and they are numerous--the egg is fixed
behind the ventral surface, on the verge of the brown patch formed by the
contents of the digestive system.

If there be nothing to guide her, what chance has the mother of gluing her
egg to this point, which is always the same because it is that most
favourable to successful rearing? A very small point, represented by the
ratio of two or three square millimetres (About 1/100 square inch.--
Translator's Note.) to the entire surface of the victim's body.

Is this all? Not yet. The grub is hatched; it pierces the belly of the
Cetonia-larva at the requisite point; it plunges its long neck into the
entrails, ransacking them and filling itself to repletion. If it bite at
random, if it have no other guide in the selection of tit-bits than the
preference of the moment and the violence of an imperious appetite, it will
infallibly incur the danger of being poisoned by putrid food, for the
victim, if wounded in those organs which preserve a remnant of life in it,
will die for good and all at the first mouthfuls.

The ample joint must be consumed with prudent skill: this part must be
eaten before that and, after that, some other portion, always according to
method, until the time approaches for the last bites. This marks the end of
life for the Cetonia, but it also marks the end of the Scolia's feasting.
If the grub be a novice in the art of eating, if no special instinct guide
its mandibles in the belly of the prey, what chance has it of completing
its perilous meal? As much as a starving Wolf would have of daintily
dissecting his Sheep, when he tears at her gluttonously, rends her into
shreds and gulps them down.

These four conditions of success, with chance so near to zero in each case,
must all be realized together, or the grub will never be reared. The Scolia
may have captured a larva with close-packed nerve-centres, a Cetonia-grub,
for instance; but this will go for nothing unless she direct her sting
towards the only vulnerable point. She may know the whole secret of the art
of stabbing her victim, but this means nothing if she does not know where
to fasten her egg. The suitable spot may be found, but all the foregoing
will be useless if the grub be not versed in the method to be followed in
devouring its prey while keeping it alive. It is all or nothing.

Who would venture to calculate the final chance on which the future of the
Scolia, or of her precursor, is based, that complex chance whose factors
are four infinitely improbable occurrences, one might almost say four
impossibilities? And such a conjunction is supposed to be a fortuitous
result, to which the present instinct is due! Come, come!

>From another point of view again, the Darwinian theory is at variance with
the Scoliae and their prey. In the heap of garden mould which I exploited
in order to write this record, three kinds of larvae dwell together,
belonging to the Scarabaeid group: the Cetonia, the Oryctes and Scarabeus
pentodon. Their internal structure is very nearly similar; their food is
the same, consisting of decomposing vegetable matter; their habits are
identical: they live underground in tunnels which are frequently renewed;
they make a rough egg-shaped cocoon of earthy materials. Environment, diet,
industry and internal structure are all similar; and yet one of these three
larvae, the Cetonia's, reveals a most singular dissimilarity from its
fellow-trenchermen: alone among the Scarabaeidae and, more than that, alone
in all the immense order of insects, it walks upon its back.

If the differences were a matter of a few petty structural details, falling
within the finical department of the classifier, we might pass them over
without hesitation; but a creature that turns itself upside down in order
to walk with its belly in the air and never adopts any other method of
locomotion, though it possesses legs and good legs at that, assuredly
deserves examination. How did the animal acquire its fantastic mode of
progress and why does it think fit to walk in a fashion the exact contrary
of that adopted by other beasts?

To these questions the science now in fashion always has a reply ready:
adaptation to environment. The Cetonia-larva lives in crumbling galleries
which it bores in the depths of the soil. Like the sweep who obtains a
purchase with his back, loins and knees to hoist himself up the narrow
passage of a chimney, it gathers itself up, applies the tip of its belly to
one wall of its gallery and its sturdy back to another; and the combined
effort of these two levers results in moving it forward. The legs, which
are used very little, indeed hardly at all, waste away and tend to
disappear, as does any organ which is left unemployed; the back, on the
other hand, the principal motive agent, grows stronger, is furrowed with
powerful folds and bristles with grappling-hooks or hairs; and gradually,
by adaptation to its environment, the creature loses the art of walking,
which it does not practise, and replaces it by that of crawling on its
back, a form of progress better suited to underground corridors.

So far so good. But now tell me, if you please, why the larvae of the
Oryctes and the Scarabaeus, living in vegetable mould, the larva of the
Anoxia, dwelling in the sand, and the larva of the Cockchafer in our
cultivated fields have not also acquired the faculty of walking on their
backs? In their galleries they follow the chimney-sweep's methods quite as
cleverly as the Cetonia-grub; to move forward they make valiant use of
their backs without yet having come to ambling with their bellies in the
air. Can they have neglected to accommodate themselves to the demands of
their environment? If evolution and environment cause the topsy-turvy
progress of the one, I have the right, if words have any meaning whatever,
to demand as much of the others, since their organization is so much alike
and their mode of life identical.

I have but little respect for theories which, when confronted with two
similar cases, are unable to interpret the one without contradicting the
other. They make me laugh when they become merely childish. For example:
why has the tiger a coat streaked black and yellow? A matter of
environment, replies one of our evolutionary masters. Ambushed in bamboo
thickets where the golden radiance of the sun is intersected by stripes of
shadow cast by the foliage, the animal, the better to conceal itself,
assumed the colour of its environment. The rays of the sun produced the
tawny yellow of the coat; the stripes of shadow added the black bars.

And there you have it. Any one who refuses to accept the explanation must
be very hard to please. I am one of these difficult persons. If it were a
dinner-table jest, made over the walnuts and the wine, I would willingly
sing ditto; but alas and alack, it is uttered without a smile, in a solemn
and magisterial manner, as the last word in science! Toussenel, in his day,
asked the naturalists an insidious question. (Alphonse Toussenel (1803-
1885), the author of a number of learned and curious works on ornithology.-
-Translator's Note.) Why, he enquired, have Ducks a little curly feather on
the rump? No one, so far as I know, had an answer for the teasing cross-
examiner: evolution had not been invented then. In our time the reason why
would be forthcoming in a moment, as lucid and as well-founded as the
reason why of the tiger's coat.

Enough of childish nonsense. The Cetonia-grub walks on its back because it
has always done so. The environment does not make the animal; it is the
animal that is made for the environment. To this simple philosophy, which
is quite antiquated nowadays, I will add another, which Socrates expressed
in these words:

"What I know best is that I know nothing."





Next: THE TACHYTES

Previous: THE CETONIA-LARVA



Add to del.icio.us Add to Reddit Add to Digg Add to Del.icio.us Add to Google Add to Twitter Add to Stumble Upon
Add to Informational Site Network
Report
Privacy
SHAREADD TO EBOOK