SOME REFLECTIONS UPON INSECT PSYCHOLOGY
The laudator temperis acti is out of favour just now: the world is on
the move. Yes, but sometimes it moves backwards. When I was a boy, our
twopenny textbooks told us that man was a reasoning animal; nowadays,
there are learned volumes to prove to us that human reason is but a
higher rung in the ladder whose foot reaches down to the bottommost
depths of animal life. There is the greater and the lesser; there are
all t
e intermediary rounds; but nowhere does it break off and start
afresh. It begins with zero in the glair of a cell and ascends until
we come to the mighty brain of a Newton. The noble faculty of which we
were so proud is a zoological attribute. All have a larger or smaller
share of it, from the live atom to the anthropoid ape, that hideous
caricature of man.
It always struck me that those who held this levelling theory made
facts say more than they really meant; it struck me that, in order to
obtain their plain, they were lowering the mountain-peak, man, and
elevating the valley, the animal. Now this levelling of theirs needed
proofs, to my mind; and, as I found none in their books, or at any
rate only doubtful and highly debatable ones, I did my own observing,
in order to arrive at a definite conviction; I sought; I experimented.
To speak with any certainty, it behoves us not to go beyond what we
really know. I am beginning to have a passable acquaintance with
insects, after spending some forty years in their company. Let us
question the insect, then: not the first that comes along, but the
most gifted, the Hymenopteron. I am giving my opponents every
advantage. Where will they find a creature more richly endowed with
talent? It would seem as though, in creating it, nature had delighted
in bestowing the greatest amount of industry upon the smallest body of
matter. Can the bird, wonderful architect that it is, compare its work
with that masterpiece of higher geometry, the edifice of the Bee? The
Hymenopteron rivals man himself. We build towns, the Bee erects
cities; we have servants, the Ant has hers; we rear domestic animals,
she rears her sugar-yielding insects; we herd cattle, she herds her
milch-cows, the Aphides; we have abolished slavery, whereas she
continues her nigger-traffic.
Well, does this superior, this privileged being reason? Reader, do not
smile: this is a most serious matter, well worthy of our
consideration. To devote our attention to animals is to plunge at once
into the vexed question of who we are and whence we come. What, then,
passes in that little Hymenopteron brain? Has it faculties akin to
ours, has it the power of thought? What a problem, if we could only
solve it; what a chapter of psychology, if we could only write it!
But, at our very first questionings, the mysterious will rise up,
impenetrable: we may be convinced of that. We are incapable of knowing
ourselves; what will it be if we try to fathom the intellect of
others? Let us be content if we succeed in gleaning a few grains of
truth.
What is reason? Philosophy would give us learned definitions. Let us
be modest and keep to the simplest: we are only treating of animals.
Reason is the faculty that connects the effect with its cause and
directs the act by conforming it to the needs of the accidental.
Within these limits, are animals capable of reasoning? Are they able
to connect a 'because' with a 'why' and afterwards to regulate their
behaviour accordingly? Are they able to change their line of conduct
when faced with an emergency?
History has but few data likely to be of use to us here; and those
which we find scattered in various authors are seldom able to
withstand a severe examination. One of the most remarkable of which I
know is supplied by Erasmus Darwin, in his book entitled "Zoonomia."
It tells of a Wasp that has just caught and killed a big Fly. The wind
is blowing; and the huntress, hampered in her flight by the great area
presented by her prize, alights on the ground to amputate the abdomen,
the head and the wings; she flies away, carrying with her only the
thorax, which gives less hold to the wind. If we keep to the bald
facts, this does, I admit, give a semblance of reason. The Wasp
appears to grasp the relation between cause and effect. The effect is
the resistance experienced in the flight; the cause is the dimensions
of the prey contending with the air. Hence the logical conclusion:
those dimensions must be lessened; the abdomen, the head and, above
all, the wings must be chopped off; and the resistance will be
decreased. (I would gladly, if I were able, cancel some rather hasty
lines which I allowed myself to pen in the first volume of these
"Souvenirs" but scripta manent. All that I can do is to make amends
now, in this note, for the error into which I fell. Relying on
Lacordaire, who quotes this instance from Erasmus Darwin in his own
"Introduction a l'entomologie", I believed that a Sphex was given as
the heroine of the story. How could I do otherwise, not having the
original text in front of me? How could I suspect that an entomologist
of Lacordaire's standing should be capable of such a blunder as to
substitute a Sphex for a Common Wasp? Great was my perplexity, in the
face of this evidence! A Sphex capturing a Fly was an impossibility;
and I blamed the British scientist accordingly. But what insect was it
that Erasmus Darwin saw? Calling logic to my aid, I declared that it
was a Wasp; and I could not have hit the mark more truly. Charles
Darwin, in fact, informed me afterwards that his grandfather wrote 'a
Wasp' in his "Zoonomia." Though the correction did credit to my
intelligence, I none the less deeply regretted my mistake, for I had
uttered suspicions of the observer's powers of discernment, unjust
suspicions which the translator's inaccuracy led me into entertaining.
May this note serve to mitigate the harshness of the strictures
provoked by my overtaxed credulity! I do not scruple to attack ideas
which I consider false; but Heaven forfend that I should ever attack
those who uphold them!--Author's Note.)
But does this concatenation of ideas, rudimentary though it be, really
take place within the insect's brain? I am convinced of the contrary;
and my proofs are unanswerable. In the first volume of these
"Souvenirs" (Cf. "Insect Life": chapter 9.--Translator's Note.), I
demonstrated by experiment that Erasmus Darwin's Wasp was but obeying
her instinct, which is to cut up the captured game and to keep only
the most nourishing part, the thorax. Whether the day be perfectly
calm or whether the wind blow, whether she be in the shelter of a
dense thicket or in the open, I see the Wasp proceed to separate the
succulent from the tough; I see her reject the legs, the wings, the
head and the abdomen, retaining only the breast as pap for her larvae.
Then what value has this dissection as an argument in favour of the
insect's reasoning-powers when the wind blows? It has no value at all,
for it would take place just the same in absolutely calm weather.
Erasmus Darwin jumped too quickly to his conclusion, which was the
outcome of his mental bias and not of the logic of things. If he had
first enquired into the Wasp's habits, he would not have brought
forward as a serious argument an incident which had no connection with
the important question of animal reason.
I have reverted to this case to show the difficulties that beset the
man who confines himself to casual observations, however carefully
carried out. One should never rely upon a lucky chance, which may not
occur again. We must multiply our observations, check them one with
the other; we must create incidents, looking into preceding ones,
finding out succeeding ones and working out the relation between them
all: then and not till then, with extreme caution, are we entitled to
express a few views worthy of credence. Nowhere do I find data
collected under such conditions; for which reason, however much I
might wish it, it is impossible for me to bring the evidence of others
in support of the few conclusions which I myself have formed.
My Mason-bees, with their nests hanging on the walls of the arch which
I have mentioned, lent themselves to continuous experiment better than
any other Hymenopteron. I had them there, at my house, under my eyes,
at all hours of the day, as long as I wished. I was free to follow
their actions in full detail and to carry out successfully any
experiment, however long. Moreover, their numbers allowed me to repeat
my attempts until I was perfectly convinced. The Mason-bees,
therefore, shall supply me with the materials for this chapter also.
A few words, before I begin, about the works. The Mason-bee of the
Sheds utilizes, first of all, the old galleries of the clay nest, a
part of which she good-naturedly abandons to two Osmiae, her free
tenants: the Three-horned Osmia and Latreille's Osmia. These old
corridors, which save labour, are in great demand; but there are not
many vacant, as the more precocious Osmiae have already taken
possession of most of them; and therefore the building of new cells
soon begins. These cells are cemented to the surface of the nest,
which thus increases in thickness every year. The edifice of cells is
not built all at once: mortar and honey alternate repeatedly. The
masonry starts with a sort of little swallow's nest, a half-cup or
thimble, whose circumference is completed by the wall against which it
rests. Picture the cup of an acorn cut in two and stuck to the surface
of the nest: there you have the receptacle in a stage sufficiently
advanced to take a first instalment of honey.
The Bee thereupon leaves the mortar and busies herself with
harvesting. After a few foraging-trips, the work of building is
resumed; and some new rows of bricks raise the edge of the basin,
which becomes capable of receiving a larger stock of provisions. Then
comes another change of business: the mason once more becomes a
harvester. A little later, the harvester is again a mason; and these
alternations continue until the cell is of the regulation height and
holds the amount of honey required for the larva's food. Thus come,
turn and turn about, more or less numerous according to the occupation
in hand, journeys to the dry and barren path, where the cement is
gathered and mixed, and journeys to the flowers, where the Bee's crop
is crammed with honey and her belly powdered with pollen.
At last comes the time for laying. We see the Bee arrive with a pellet
of mortar. She gives a glance at the cell to enquire if everything is
in order; she inserts her abdomen; and the egg is laid. Then and there
the mother seals up the home: with her pellet of cement she closes the
orifice and manages so well with the material that the lid receives
its permanent form at this first sitting; it has only to be thickened
and strengthened with fresh layers, a work which is less urgent and
will be done by and by. What does appear to be an urgent necessity is
the closing of the cell immediately after the egg has been religiously
deposited therein, so that there may be no danger from evilly-disposed
visitors during the mother's absence. The Bee must have serious
reasons for thus hurrying on the closing of the cell. What would
happen if, after laying her egg, she left the house open and went to
the cement-pit to fetch the wherewithal to block the door? Some thief
might drop in and substitute her own egg for the Mason-bee's. We shall
see that our suspicions are not uncalled-for. One thing is certain,
that the Mason never lays without having in her mandibles the pellet
of mortar required for the immediate construction of the lid of the
nest. The precious egg must not for a single instant remain exposed to
the cupidity of marauders.
To these particulars I will add a few general observations which will
make what follows easier to understand. So long as its circumstances
are normal, the insect's actions are calculated most rationally in
view of the object to be attained. What could be more logical, for
instance, than the devices employed by the Hunting Wasp when
paralysing her prey (Cf. "Insect Life": chapters 3 to 12 and 15 to
17.--Translator's Note.) so that it may keep fresh for her larva,
while in no wise imperilling that larva's safety? It is preeminently
rational; we ourselves could think of nothing better; and yet the
Wasp's action is not prompted by reason. If she thought out her
surgery, she would be our superior. It will never occur to anybody
that the creature is able, in the smallest degree, to account for its
skilful vivisections. Therefore, so long as it does not depart from
the path mapped out for it, the insect can perform the most sagacious
actions without entitling us in the least to attribute these to the
dictates of reason.
What would happen in an emergency? Here we must distinguish carefully
between two classes of emergency, or we shall be liable to grievous
error. First, in accidents occurring in the course of the insect's
occupation at the moment. In these circumstances, the creature is
capable of remedying the accident; it continues, under a similar form,
its actual task; it remains, in short; in the same psychic condition.
In the second case, the accident is connected with a more remote
occupation; it relates to a completed task with which, under normal
conditions, the insect is no longer concerned. To meet this emergency,
the creature would have to retrace its psychic course; it would have
to do all over again what it has just finished, before turning its
attention to anything else. Is the insect capable of this? Will it be
able to leave the present and return to the past? Will it decide to
hark back to a task that is much more pressing than the one on which
it was engaged? If it did all this, then we should really have
evidence of a modicum of reason. The question shall be settled by
experiment.
We will begin by taking a few incidents that come under the first
heading. A Mason-bee has finished the initial layer of the covering of
the cell. She has gone in search of a second pellet of mortar
wherewith to strengthen her work. In her absence, I prick the lid with
a needle and widen the hole thus made, until it is half the size of
the opening. The insect returns and repairs the damage. It was
originally engaged on the lid and is merely continuing its work in
mending that lid.
A second is still at her first row of bricks. The cell as yet is no
more than a shallow cup, containing no provisions. I make a big hole
in the bottom of the cup and the Bee hastens to stop the breach. She
was busy building and turned aside a moment to do more building. Her
repairs are the continuation of the work on which she was engaged.
A third has laid her egg and closed the cell. While she is gone in
search of a fresh supply of cement to strengthen the door, I make a
large aperture immediately below the lid, too high up to allow the
honey to escape. The insect, on arriving with its mortar intended for
a different task, sees its broken jar and soon puts the damage right.
I have rarely witnessed such a sensible performance. Nevertheless, all
things considered, let us not be too lavish of our praises. The insect
was busy closing up. On its return, it sees a crack, representing in
its eyes a bad join which it had overlooked; it completes its actual
task by improving the join.
The conclusion to be drawn from these three instances, which I select
from a large number of others, more or less similar, is that the
insect is able to cope with emergencies, provided that the new action
be not outside the course of its actual work at the moment. Shall we
say then that reason directs it? Why should we? The insect persists in
the same psychic course, it continues its action, it does what it was
doing before, it corrects what to it appears but a careless flaw in
the work of the moment.
Here, moreover, is something which would change our estimate entirely,
if it ever occurred to us to look upon these repaired breaches as a
work dictated by reason. Let us turn to the second class of emergency
referred to above: let us imagine, first, cells similar to those in
the second experiment, that is to say, only half-finished, in the form
of a shallow cup, but already containing honey. I make a hole in the
bottom, through which the provisions ooze and run to waste. Their
owners are harvesting. Let us imagine, on the other hand, cells very
nearly finished and almost completely provisioned. I perforate the
bottom in the same way and let out the honey, which drips through
gradually. The owners of these are building.
Judging by what has gone before, the reader will perhaps expect to see
immediate repairs, urgent repairs, for the safety of the future larva
is at stake. Let him dismiss any such illusion: more and more journeys
are undertaken, now in quest of food, now in quest of mortar; but not
one of the Mason-bees troubles about the disastrous breach. The
harvester goes on harvesting; the busy bricklayer proceeds with her
next row of bricks, as though nothing out of the way had happened.
Lastly, if the injured cells are high enough and contain enough
provisions, the Bee lays her eggs, puts a door to the house and passes
on to another house, without doing aught to remedy the leakage of the
honey. Two or three days later, those cells have lost all their
contents, which now form a long trail on the surface of the nest.
Is it through lack of intelligence that the Bee allows her honey to go
to waste? May it not rather be through helplessness? It might happen
that the sort of mortar which the Mason has at her disposal will not
set on the edges of a hole that is sticky with honey. The honey may
prevent the cement from adjusting itself to the orifice, in which case
the insect's inertness would merely be resignation to an irreparable
evil. Let us look into the matter before drawing inferences. With my
forceps, I deprive the Bee of her pellet of mortar and apply it to the
hole whence the honey is escaping. My attempt at repairing meets with
the fullest success, though I do not pretend to compete with the Mason
in dexterity. For a piece of work done by a man's hand it is quite
creditable. My dab of mortar fits nicely into the mutilated wall; it
hardens as usual; and the escape of honey ceases. This is quite
satisfactory. What would it be had the work been done by the insect,
equipped with its tools of exquisite precision? When the Mason-bee
refrains, therefore, this is not due to helplessness on her part, nor
to any defect in the material employed.
Another objection presents itself. We are going too far perhaps in
admitting this concatenation of ideas in the insect's mind, in
expecting it to argue that the honey is running away because the cell
has a hole in it and that to save it from being wasted the hole must
be stopped. So much logic perhaps exceeds the powers of its poor
little brain. Then, again, the hole is not seen; it is hidden by the
honey trickling through. The cause of that stream of honey is an
unknown cause; and to trace the loss of the liquid home to that cause,
to the hole in the receptacle, is too lofty a piece of reasoning for
the insect.
A cell in the rudimentary cup-stage and containing no provisions has a
hole, three or four millimetres (.11 to .15 inch.--Translator's Note.)
wide, made in it at the bottom. A few moments later, this orifice is
stopped by the Mason. We have already witnessed a similar patching.
The insect, having finished, starts foraging. I reopen the hole at the
same place. The pollen runs through the aperture and falls to the
ground as the Bee is rubbing off her first load in the cell. The
damage is undoubtedly observed. When plunging her head into the cup to
take stock of what she has stored, the Bee puts her antennae into the
artificial hole: she sounds it, she explores it, she cannot fail to
perceive it.
I see the two feelers quivering outside the hole. The insect notices
the breach in the wall: that is certain. It flies off. Will it bring
back mortar from its present journey to repair the injured jar as it
did just now?
Not at all. It returns with provisions, it disgorges its honey, it
rubs off its pollen, it mixes the material. The sticky and almost
solid mass fills up the opening and oozes through with difficulty. I
roll a spill of paper and free the hole, which remains open and shows
daylight distinctly in both directions. I sweep the place clear over
and over again, whenever this becomes necessary because new provisions
are brought; I clean the opening sometimes in the Bee's absence,
sometimes in her presence, while she is busy mixing her paste. The
unusual happenings in the warehouse plundered from below cannot escape
her any more than the ever-open breach at the bottom of the cell.
Nevertheless, for three consecutive hours, I witness this strange
sight: the Bee, full of active zeal for the task in hand, omits to
plug this vessel of the Danaides. She persists in trying to fill her
cracked receptacle, whence the provisions disappear as soon as stored
away. She constantly alternates between builder's and harvester's
work; she raises the edges of the cell with fresh rows of bricks; she
brings provisions which I continue to abstract, so as to leave the
breach always visible. She makes thirty-two journeys before my eyes,
now for mortar, now for honey, and not once does she bethink herself
of stopping the leakage at the bottom of her jar.
At five o'clock in the evening, the works cease. They are resumed on
the morrow. This time, I neglect to clean out my artificial orifice
and leave the victuals gradually to ooze out by themselves. At length,
the egg is laid and the door sealed up, without anything being done by
the Bee in the matter of the disastrous breach. And yet to plug the
hole were an easy matter for her: a pellet of her mortar would
suffice. Besides, while the cup was still empty, did she not instantly
close the hole which I had made? Why are not those early repairs of
hers repeated? It clearly shows the creature's inability to retrace
the course of its actions, however slightly. At the time of the first
breach, the cup was empty and the insect was laying the first rows of
bricks. The accident produced through my agency concerned the part of
the work which occupied the Bee at the actual moment; it was a flaw in
the building, such as can occur naturally in new courses of masonry,
which have not had time to harden. In correcting that flaw, the Mason
did not go outside her usual work.
But, once the provisioning begins, the cup is finished for good and
all; and, come what may, the insect will not touch it again. The
harvester will go on harvesting, though the pollen trickle to the
ground through the drain. To plug the hole would imply a change of
occupation of which the insect is incapable for the moment. It is the
honey's turn and not the mortar's. The rule upon this point is
invariable. A moment comes, presently, when the harvesting is
interrupted and the masoning resumed. The edifice must be raised a
storey higher. Will the Bee, once more a builder, mixing fresh cement,
now attend to the leakage at the bottom? No more than before. What
occupies her at present is the new floor, whose brickwork would be
repaired at once, if it sustained a damage; but the bottom storey is
too old a part of the business, it is ancient history; and the worker
will not put a further touch to it, even though it be in serious
danger.
For the rest, the present and the following storeys will all have the
same fate. Carefully watched by the insect as long as they are in
process of building, they are forgotten and allowed to go to ruin once
they are actually built. Here is a striking instance: in a cell which
has attained its full height, I make a window, almost as large as the
natural opening, and place it about half-way up, above the honey. The
Bee brings provisions for some time longer and then lays her egg.
Through my big window, I see the egg deposited on the victuals. The
insect next works at the cover, to which it gives the finishing
touches with a series of little taps, administered with infinite care,
while the breach remains yawning. On the lid, it scrupulously stops up
every pore that could admit so much as an atom; but it leaves the
great opening that places the house at the mercy of the first-comer.
It goes to that breach repeatedly, puts in its head, examines it,
explores it with its antennae, nibbles the edges of it. And that is
all. The mutilated cell shall stay as it is, with never a dab of
mortar. The threatened part dates too far back for the Bee to think of
troubling about it.
I have said enough, I think, to show the insect's mental incapacity in
the presence of the accidental. This incapacity is confirmed by
renewing the test, an essential condition of all good experiments;
therefore my notes are full of examples similar to the one which I
have just described. To relate them would be mere repetition; I pass
them over for the sake of brevity.
The renewal of a test is not sufficient: we must also vary our test.
Let us, then, examine the insect's intelligence from another point of
view, that of the introduction of foreign bodies into the cell. The
Mason-bee is a housekeeper of scrupulous cleanliness, as indeed are
all the Hymenoptera. Not a spot of dirt is suffered in her honey-pot;
not a grain of dust is permitted on the surface of her mixture. And
yet, while the jar is open, the precious Bee-bread is exposed to
accidents. The workers in the cells above may inadvertently drop a
little mortar into the lower cells; the owner herself, when working at
enlarging the jar, runs the risk of letting a speck of cement fall
into the provisions. A Gnat, attracted by the smell, may come and be
caught in the honey; brawls between neighbours who are getting into
each other's way may send some dust flying thither. All this refuse
has to disappear and that quickly, lest afterwards the larva should
find coarse fare under its delicate mandibles. Therefore the Mason-
bees must be able to cleanse the cell of any foreign body. And, in
point of fact, they are well able to do so.
I place on the surface of the honey five or six bits of straw a
millimetre in length. (.039 inch.--Translator's Note.) Great
astonishment on the part of the returning insect. Never before have so
many sweepings accumulated in its warehouse. The Bee picks out the
bits of straw, one by one, to the very last, and each time goes and
gets rid of them at a distance. The effort is out of all proportion to
the work: I see the Bee soar above the nearest plane-tree, to a height
of thirty feet, and fly away beyond it to rid herself of her burden, a
mere atom. She fears lest she should litter the place by dropping her
bit of straw on the ground, under the nest. A thing like that must be
carried very far away.
I place upon the honey-paste a Mason-bee's egg which I myself saw laid
in an adjacent cell. The Bee picks it out and throws it away at a
distance, as she did with the straws just now. There are two
inferences to be drawn from this, both extremely interesting. In the
first place, that precious egg, for whose future the Bee labours so
indefatigably, becomes a valueless, cumbersome, hateful thing when it
belongs to another. Her own egg is everything; the egg of her next
door neighbour is nothing. It is flung on the dust-heap like any bit
of rubbish. The individual, so zealous on behalf of her family,
displays an abominable indifference for the rest of her kind. Each one
for himself. In the second place, I ask myself, without as yet being
able to find an answer to my question, how certain parasites go to
work to give their larva the benefit of the provisions accumulated by
the Mason-bee. If they decide to lay their egg on the victuals in the
open cell, the Bee, when she sees it, will not fail to cast it out; if
they decide to lay after the owner, they cannot do so, for she blocks
up the door as soon as her laying is done. This curious problem must
be reserved for future investigation. (Cf. "The Life of the Fly":
chapters 2 to 4; also later chapters in the present volume.--
Translator's Note.)
Lastly, I stick into the paste a bit of straw nearly an inch long and
standing well out above the rim of the cell. The insect extracts it by
dint of great efforts, dragging it away from one side; or else, with
the help of its wings, it drags it from above. It darts away with the
honey-smeared straw and gets rid of it at a distance, after flying
over the plane-tree.
This is where things begin to get complicated. I have said that, when
the time comes for laying, the Mason-bee arrives with a pellet of
mortar wherewith immediately to make a door to the house. The insect,
with its front legs resting on the rim, inserts its abdomen in the
cell; it has the mortar ready in its mouth. Having laid the egg, it
comes out and turns round to block the door. I wave it away for a
second, at the same time planting my straw as before, a straw sticking
out nearly a centimetre. (.39 inch.--Translator's Note.) What will the
Bee do? Will she, who is scrupulous in ridding the home of the least
mote of dust, extract this beam, which would certainly prove the
larva's undoing by interfering with its growth? She could, for just
now we saw her drag out and throw away, at a distance, a similar beam.
She could and she doesn't. She closes the cell, cements the lid, seals
up the straw in the thickness of the mortar. More journeys are taken,
not a few, in search of the cement required to strengthen the cover.
Each time, the mason applies the material with the most minute care,
while giving the straw not a thought. In this way, I obtain, one after
the other, eight closed cells whose lids are surmounted by my mast, a
bit of protruding straw. What evidence of obtuse intelligence!
This result is deserving of attentive consideration. At the moment
when I am inserting my beam, the insect has its mandibles engaged:
they are holding the pellet of mortar intended for the blocking-
operation. As the extracting-tool is not free, the extraction does not
take place. I expected to see the Bee relinquish her mortar and then
proceed to remove the encumbrance. A dab of mortar more or less is not
a serious business. I had already noticed that it takes my Mason-bees
a journey of three or four minutes to collect one. The pollen-
expeditions last longer, a matter of ten or fifteen minutes. To drop
her pellet, grab the straw with her mandibles, now disengaged, remove
it and gather a fresh supply of cement would entail a loss of five
minutes at most. The Bee decides differently. She will not, she cannot
relinquish her pellet; and she uses it. No matter that the larva will
perish by this untimely trowelling: the moment has come to wall up the
door; the door is walled up. Once the mandibles are free, the
extraction could be attempted, at the risk of wrecking the lid. But
the Bee does nothing of the sort: she keeps on fetching mortar; and
the lid is religiously finished.
We might go on to say that, if the Bee were obliged to depart in quest
of fresh mortar after dropping the first to withdraw the straw, she
would leave the egg unguarded and that this would be an extreme
measure which the mother cannot bring herself to adopt. Then why does
she not place the pellet on the rim of the cell? The mandibles, now
free, would remove the beam; the pellet would be taken up again at
once; and everything would go to perfection. But no: the insect has
its mortar and, come what may, employs it on the work for which it was
intended.
If any one sees a rudiment of reason in this Hymenopteron
intelligence, he has eyes that are more penetrating than mine. I see
nothing in it all but an invincible persistence in the act once begun.
The cogs have gripped; and the rest of the wheels must follow. The
mandibles are fastened on the pellet of mortar; and the idea, the wish
to unfasten them will never occur to the insect until the pellet has
fulfilled its purpose. And here is a still greater absurdity: the
plugging once begun is very carefully finished with fresh relays of
mortar! Exquisite attention is paid to a closing-up which is
henceforth useless; no attention at all to the dangerous beam. O
little gleams of reason that are said to enlighten the animal, you are
very near the darkness, you are naught!
Another and still more eloquent fact will finally convince whoso may
yet be doubting. The ration of honey stored up in a cell is evidently
measured by the needs of the coming larva. There is neither too much
nor too little. How does the Bee know when the proper quantity is
reached? The cells are more or less constant in dimension, but they
are not filled completely, only to about two-thirds of their height. A
large space is therefore left empty; and the victualler has to judge
of the moment when the surface of the mess has attained the right
level. The honey being perfectly opaque, its depth is not apparent. I
have to use a sounding-rod when I want to gauge the contents of the
jar; and I find, on the average, that the honey reaches a depth of ten
millimetres. (.39 inch.--Translator's Note.) The Bee has not this
resource; she has sight, which may enable her to estimate the full
section from the empty section. This presupposes the possession of a
somewhat geometric eye, capable of measuring the third of a distance.
If the insect did it by Euclid, that would be very brilliant of it.
What a magnificent proof in favour of its little intellect: a
Chalicodoma with a geometrician's eye, able to divide a straight line
into three equal parts! This is worth looking into seriously.
I take five cells, which are only partly provisioned, and empty them
of their honey with a wad of cotton held in my forceps. From time to
time, as the Bee brings new provisions, I repeat the cleansing-
process, sometimes clearing out the cell entirely, sometimes leaving a
thin layer at the bottom. I do not observe any pronounced hesitation
on the part of my plundered victims, even though they surprise me at
the moment when I am draining the jar; they continue their work with
quiet industry. Sometimes, two or three threads of cotton remain
clinging to the walls of the cells: the Bees remove them carefully and
dart away to a distance, as usual, to get rid of them. At last, a
little sooner or a little later, the egg is laid and the lid fastened
on.
I break open the five closed cells. In one, the egg has been laid on
three millimetres of honey (.117 inch.--Translator's Note.); in two,
on one millimetre (.039 inch.--Translator's Note.); and, in the two
others, it is placed on the side of the receptacle drained of all its
contents, or, to be more accurate, having only the glaze, the varnish
left by the friction of the honey-covered cotton.
The inference is obvious: the Bee does not judge of the quantity of
honey by the elevation of the surface; she does not reason like a
geometrician, she does not reason at all. She accumulates so long as
she feels within her the secret impulse that prompts her to go on
collecting until the victualling is completed; she ceases to
accumulate when that impulse is satisfied, irrespective of the result,
which in this case happens to be worthless. No mental faculty,
assisted by sight, informs her when she has enough, or when she has
too little. An instinctive predisposition is her only guide, an
infallible guide under normal conditions, but hopelessly lost when
subjected to the wiles of the experimenter. Had the Bee the least
glimmer of reason would she lay her egg on the third, on the tenth
part of the necessary provender? Would she lay it in an empty cell?
Would she be guilty of such inconceivable maternal aberration as to
leave her nurseling without nourishment? I have told the story; let
the reader decide.
This instinctive predisposition, which does not leave the insect free
to act and, through that very fact, saves it from error, bursts forth
under yet another aspect. Let us grant the Bee as much judgment as you
please. Thus endowed, will she be capable of meting out the future's
larva's portion? By no means. The Bee does not know what that portion
is. There is nothing to tell the materfamilias; and yet, at her first
attempt, she fills the honey-pot to the requisite depth. True, in her
childhood she received a similar ration, but she consumed it in the
darkness of a cell; and besides, as a grub, she was blind. Sight was
not her informant: it did not tell her the quantity of the provisions.
Did memory, the memory of the stomach that once digested them? But
digestion took place a year ago; and since that distant epoch, the
nurseling, now an adult insect, has changed its shape, its dwelling,
its mode of life. It was a grub; it is a Bee. Does the actual insect
remember that childhood's meal? No more than we remember the sups of
milk drawn from our mother's breast. The Bee, therefore, knows nothing
of the quantity of provisions needed by her larva, whether from
memory, from example or from acquired experience. Then what guides her
when she makes her estimate with such precision? Judgment and sight
would leave the mother greatly perplexed, liable to provide too much
or not enough. To instruct her beyond the possibility of a mistake
demands a special tendency, an unconscious impulse, an instinct, an
inward voice that dictates the measure to be apportioned.