fecundation, and are conducted into the interior of the nest, commence
by being entirely dependent upon the workers. The latter, hanging to
each of their legs, guard them with assiduity, and never permit them
to go out. They nourish them with the greatest care, and conduct them
into quarters whose temperature appears the best adapted to them; but
they do not abandon them an instant. Each of these females loses, by
degrees, the desire of quitting her abode. Her abdomen increases in
size: at this period, she no longer experiences constraint. She has
still a constant guard; a single ant accompanies her every where, and
provides for her necessities. The greater part of the time the worker
rests upon its abdomen, with its posterior legs stretched out upon the
ground. It appears to be a sentinel stationed to survey the female’s
actions, and to seize the first moment when she begins to lay, to carry
off the eggs. It is not always the same ant which follows her; this is
relieved by others, who succeed it without interruption; but when the
maternity of the female is well known, they commence by rendering her
that homage which the bees evince for their queen. A court of from ten
to fifteen ants continually follow her; she is unceasingly the object
of their cares and caresses; all are eager to collect around her, offer
her nourishment, and conduct her in their mandibles, through difficult
and ascending passages. They also lead her through all the different
quarters of the ant-hill. The eggs, taken up by the labourers, at the
instant of their being laid, are collected around her. When she seeks
repose, a group of ants environ her. Several females live in the same
nest; they show no rivalry; each has her court; they pass each other
uninjured, and sustain, in common, the population of the ant-hill; but
they possess no power; which, it would seem, entirely lodges with the
neuters. However, as they receive the same honours as queen bees, I
shall sometimes give them the titles of queens.[8]
[8] “In whatever apartment,” says Gould, “a queen ant condescends to
be present, she commands obedience and respect. An universal gladness
spreads itself through the whole cell, which is expressed by particular
acts of joy and exultation. They have a peculiar way of skipping,
leaping, and standing upon their hind-legs, and prancing with the
others. These frolics they make use of, both to congratulate each
other when they meet, and to show their regard for the queen. Some of
them gently walk over her, others dance round her, and all endeavour
to exert their loyalty and affection. She is generally encircled with
a cluster of attendants, who, if you separate them from her, soon
collect themselves into a body, and inclose her in the midst. However
romantic this description may appear, it may easily be proved by an
obvious experiment. If you place a queen ant, with her retinue under a
glass, you will, in a few moments, be convinced of the honour they pay,
and esteem they entertain for her.” In reference to no rivalry being
experienced, he says, “You may sometimes expect to find two Yellow
Queens in the same colony. I have once or twice met with three. They
most usually reside in the same lodgment, and live together in perfect
harmony and union.”--T.
To give a better idea of that species of interest which the females
excite in the labourers, and the attention the latter bestow upon
them, I shall enter into some details which will sufficiently prove
their instinct.
Stopping, one day, near one of those bands of ants, who were advancing
in file, I saw a female carried by a labourer, hanging to, and
suspended by its mandibles; their teeth were crossed, and the body of
the female was rolled up, like the trunk of a butterfly. It seems a
matter of astonishment that a labourer should carry a female; but the
latter possesses the art of rolling herself up into so small a compass,
as not to restrain the movements of the former. We are fully aware
that the strength of ants is not proportioned to their diminutiveness.
I seized the female and its companion, and found them to be of the
species of Fallow Ants. Having placed them immediately in liberty,
in the midst of their companions, several surrounded the female, and
caressed her with their antennæ. At length one of the labourers, after
giving her several gentle blows with the antennæ over the head, took
her up gently by its mandibles, when she laid hold of them, and rolled
herself into a ball, under the corslet of the worker, who commenced
his route, charged with his heavy burthen, proceeding at a quick pace,
followed by the other ants, who came, from time to time, to touch the
object of their solicitude. When the bearer was fatigued, it turned
round; the female then unrolled her body, and, in place of being
carried, was dragged along by the worker, who moved in a retrograde
direction, with very little effort. Sometimes the queen stopped, for
the purpose of changing her conductor: all her court then surrounded
and offered her every mark of attention. In witnessing this scene, I
was brought to the entrance of the ant-hill, where I lost sight of the
female and her retinue.
At another time, I took some Yellow Ants from their nest, with one of
their females, and many small larvæ. I enclosed them in a glazed box,
giving them earth, and supplying them with food. This box remained in
my chamber during the whole of the winter. The ants were by no means
benumbed; they appeared to follow, in every respect, their instinct,
which was most remarkable, near the female, who, every time she
attempted to move, was surrounded by so great a multitude of workers,
that it was only by their very slow movement I could be assured of
her existence. On my too frequently visiting the chamber in which she
commonly rested, her guardians prepared for her another, at a little
distance, and conducted her to it, enticing her forward by offering her
food.
I preserved this family from the month of November to the end of April.
I then removed it to another apparatus. In lieu of a glazed box, I took
a large glass, in the bottom of which I placed a little earth. I then
covered it over with a little piece of wood, which entered about midway
into the vessel; and on the outside of this wood or plank, in which an
opening had been made, I placed a variety of plants, chosen from among
those which afford nourishment to the _pucerons_. We know that ants
are very friendly to these insects, since they furnish them with their
principal subsistence. It was in the superior part of the vessel that I
placed the ants, their female, their larvæ, and their _pucerons_. They
gathered together a little earth, which they found scattered over the
leaves, and constructed with it a little lodge, between the branches,
where they conducted their queen. In a few days they discovered a
narrow passage between the glass and the border of the plank, and
finding some moist earth underneath, they lost no time in constructing,
in this place, lodges, paths, and vaulted chambers. They transported
thither the greater part of the larvæ; but they could not so easily
introduce the female. She had descended to the border of the plank very
willingly, and endeavoured to pass the opening which lay between it
and the side of the glass. She placed her head almost every moment at
this opening, making every effort to enter, as if she were aware there
was a space underneath, where she would be more conveniently lodged.
She at length found a place of sufficient width to thrust in the
whole of her head. The ants in the lower story, rubbed her with their
mandibles, and caressed her with their antennæ, as if to invite her
to follow them. Some seized her by their mandibles; others, mounting
upon the plank, drew her by her legs towards the lower apartment. She
several successive times vainly attempted to insinuate her body. The
ants collected around her, licked her, and seemed desirous to repair
the injury her unfruitful efforts had occasioned. I now seconded the
wish of these insects. Slightly moving aside the plank, the workers
were enabled to lead the female to the bottom of her abode, without
further obstacle.
We see by these details of the conduct of the workers in regard to
females, that if they have deprived them of their liberty, and their
wings, it is with no other view than that of insuring the population
of the ant-hill, and that the condition to which nature destines them
yields, in no respect, to that of queen bees.[9]
[9] The attachment of the labourers to the females would appear to
extend even beyond the existence of the latter; for, when a pregnant
female dies, five or six labourers rest near her, and, during several
days, brush and lick her continually, either in token of lasting
affection, or that by these means they hope to reanimate her.--A.
Nature has provided, then, in two ways for the preservation of the
several species of ants; by allowing females to quit the place of their
birth to form in all places numerous establishments; and permitting
the labourers, in these communities, to retain some females, to be
assured of the continuance of each society. The communities of wasps
and humble-bees, on the contrary, are dissolved every year, and
reproduced every spring. It is thus she has created annual plants,
whose species is only preserved by seeds, whilst others subsist entire
ages, producing seed every year, which multiplies in its turn. May we
not extend this comparison to the republic of bees, whose colonies
are renewed by swarming? We know, by these great facts, that the same
hand has created both the vegetable and the insect; but it would be
wandering from our present subject to follow up these considerations,
to which we are led even by the most trifling detail.
CHAP. IV.
OF THE RELATION BETWEEN ANTS.
Of those insects that live solitary, their generation, their private
habits, the metamorphoses they undergo, and their mode of living under
each variety of change, their artifices in attacking their enemies, and
the art with which they construct their habitations, forms their whole
history. But the history of insects, living in extensive societies, is
not limited to any remarkable proceedings, or to the display of any
particular talent; it offers us a series of links depending upon common
utility, equality or superiority of rank, and the part each individual
is called upon to perform in the society of which it is a member. These
several links denote a bond of union between the different members,
that could not be preserved without the intervention of language.
Under this term I include, whatever means they possess of expressing
their desires, their wants, and even their ideas, if we may be allowed
to give this term to the impulse of instinct. It would be difficult
to explain in any other manner, that centering of all wills to one
purpose, or that species of harmony which so universally reigns in
their institutions.
We have already made known several facts, proving the sociability of
ants, whilst speaking of the education they give to the little ones of
another mother; of their conduct towards the males and females; and
of the labours they undertake in common in the construction of their
abode. But these are only to be regarded as isolated facts, which do
not show in what the true secret of this harmony consists; and it
is, doubtless, only by examining their conduct under this point of
view, and with much greater attention, that we can hope to acquire
any knowledge of the manner in which these diminutive republics are
constituted. For this end, we shall first study, daily, the relations
of ants one with the other; relations under which we have not yet
considered them, and which will merit a few moments’ consideration. Let
us take, for this purpose, the most simple and ordinary traits in the
life of these insects. The guard or sentry of the ant-hill will furnish
us with the first proof of their social relations.
We could, without doubt, irritate ants on the surface of the nest,
without alarming those in the interior, if they acted isolately, and
had no means of communicating their mutual impressions. Those who are
occupied at the bottom of their nest, removed from the scene of danger,
ignorant of what menaces their companions, could not arrive to their
assistance; but it appears, that they are quickly and well informed
of what is passing on the exterior. When we attack those without,
the most part engage in their defence with a considerable degree of
courage: there are always some, who immediately steal off and produce
alarm throughout their city; the news is communicated from quarter to
quarter, and the labourers come forward in a crowd, with every mark of
uneasiness and anger. What, however, is highly worthy our remark is,
that the ants, to whose charge the young are confided, and who inhabit
the upper stories, where the temperature is highest, warned also of the
impending danger, always governed by that extreme solicitude for their
charge, which we have so often admired, hasten to convey them to the
deepest part of their habitation, and thus deposit them in a place of
safety.
To study in detail the manner in which this alarm spreads over the
ant-hill, we must extend our observation to the individuals of the
largest species: the Herculean Ants, who inhabit hollow trees and who
quit them only in the spring, to accompany the males and females, have
very much assisted me in this object.
The labourers are from five to six lines in length; the winged
individuals are also proportionably large: they may be frequently seen
running about the trunk of an oak, at the entrance of their labyrinths.
When I disturbed those ants that were at the greatest distance from
their companions, by either observing them too closely, or blowing upon
them lightly, I saw them run towards the other ants, give them gentle
blows with their heads against the corslet, communicating to them, in
this way, their fear or anger, passing rapidly from one to the other
in a semicircular direction, and striking several times successively
against those who did not put themselves in instant motion. These,
warned of the common danger, set off immediately, describing in
their turn different curves, and stopping to strike with their heads
all those they met on their passage. In one moment the signal was
general, all the labourers ran over the surface of the tree with great
agitation, those within receiving notice of the danger, and probably
by the same means, came out in a crowd and joined this tumult. The
same signal which produced upon the workers this effect, caused a
different impression upon the males and females; as soon as one of the
labourers had informed them of their danger, they sought an asylum, and
re-entered precipitately the trunk of the tree;--not one thought of
quitting its temporary shelter, until a worker approached and gave them
the signal for flight. The solicitude of the labourers in their favour,
is manifested in the activity they display, in giving them advice
or intimating to them the order for their departure; they redouble
then the above signals, as if conscious of their understanding their
intent less readily than the companions of their labours: the latter
understand them, if I may use the expression, at half a word; however,
there are cases, where there is a necessity for their repetition, as
the following example will prove. Its detail may appear minute, but as
it is demonstrative of the ants possessing some kind of language, I
hope to ground my excuse on the importance of the subject.
The feet of the artificial ant-hill, or _ruche_, were plunged in
vessels constantly filled with water; this expedient, originally
adopted to arrest the passage of the ants, proved to them a fruitful
source of delight, for they there slaked their thirst (like
butterflies, bees, and other insects), during the great heat of summer.
One day, whilst they were assembled at the foot of the _ruche_,
occupied in licking up the little drops which filtered between the
fibres of the wood, (which they preferred to the taking it from the
bason itself,) I amused myself in disturbing them. This trifling
experiment gave rise to a scene which appeared conclusive. The greater
part of the ants immediately ascended the leg of the _ruche_; a few,
however, remained, whom my presence had not alarmed, and who continued
carousing. But one of those who had regained the _ruche_, came back
and approached one of its companions, who appeared fully absorbed in
the pleasure of drinking; it pushed it with its mandibles several
times successively, raising and lowering its head alternately, and at
length succeeded in driving it off. The officious ant then reached
another, who was engaged in the same office, and endeavoured to drive
it off also, by striking the abdomen behind; but seeing that it did
not appear to, or would not, understand its meaning, it approached the
corslet, and gave it two or three blows with the end of its mandibles.
The ant, being at length apprised of the necessity of withdrawing,
passed precipitately to the bell-glass; a third, warned in the same
manner, and by the same ant, quickly regained its habitation; but
a fourth, who remained alone at the water’s edge, would not retire,
notwithstanding numerous proofs of the solicitude of which it was the
object:--it appeared to pay no attention to the reiterated blows of
its friendly monitor, who at length seized it by one of its legs, and
dragged it away rather roughly. The toper, however, returned, keeping
his large pincers extended with all the appearance of rage, and again
stationed himself to quaff the delightful beverage; but its companion
would give it no quarter; coming in front, it seized it by its
mandibles, and dragged it very rapidly into the ant-hill.
These observations show us in what manner the ants are understood, when
they wish to give friendly notice of the danger with which they believe
themselves threatened. Let us now pass on to the means they employ for
directing their course in their journeys and emigrations.
2. _Of the Manner in which Ants are guided in their several Excursions._
An ingenious idea, offered by a man of celebrity, is sometimes
sufficient to fix the opinion of naturalists, who would rather adopt
his idea than take the trouble of examining for themselves. It is thus,
that M. Bonnet, in comparing the odour from ants to those threads which
caterpillars, living in a republic, leave after them, has concluded,
that these insects are guided only by smell. He remarked, that he could
arrest the passage of ants, by passing his finger occasionally across
their path; but he had not perhaps reflected, that the odour from his
hand was a sufficient barrier to their progress: this experiment,
however, is not always attended with the same success. Some ants are
stopped at the moment, by the new sensation they experience, but the
greater part pass boldly the space, where we should have imagined the
invisible traces of their passage interrupted. I put them to a more
difficult trial, by digging around their nest a ditch several inches
in depth. They appeared at first to hesitate as to their movement,
but they did not forget the direction of their ant-hill, knowing the
way of returning to it, although the road in this part was completely
destroyed. When they had traversed this furrow, they often returned
behind, exploring the ground, as if to observe their route for the
purpose of again remembering it.
Why exclude sight, touch, and memory, from the part they take in
regulating the conduct of ants? Objects, which by us would be passed
unnoticed on account of their diminutiveness, may be very remarkable
with respect to them. We may be convinced by what follows, of the
fidelity of their memory, and of the subtilty of their senses.
If ants had nothing to direct them in their journeys but the odour
they leave after them, how could they possibly ascertain their route
when continued rains have soaked the ground they are to run over,
and effaced the traces of their steps, or when violent winds have
dispersed their emanations. One would think they would be thrown in
disorder; this however is not the case: they find again the places
they before frequented, go considerable distances to seek provisions;
and know every route which leads to the ant-hill.--I do not deny that
the sense of smelling may be one of the means they possess in tracing
their route, but there are circumstances in which sensations in that
way would throw them into the greatest perplexity. We well know that
several wild deer will deceive the best dogs of chace, by retracting
their steps in their several turnings and windings;--the ants would be
deceived in like manner by the emanation from their companions, if they
possessed not the knowledge of places, from the inspection of objects,
the memory of localities, or from other resources, to us unknown.
I have often amused myself by dispersing in my chamber the fragments
of one of their nests. I expected to see the ants follow each others’
track, and move in one unbroken chain (as we find to be the case with
caterpillars) to seek a place of shelter; but this was not the plan
they followed; they diverged on all sides and took a thousand different
routes: each pursued his own way. They encountered each other at
different points without appearing to have the slightest idea of any
clue that might direct them. I saw them for a long time wandering about
at random before they found a place where they could all assemble. One
of them having discovered in the flooring a little chink through which
it could glide into a darkened cavity, returned to its companions, and,
by means of certain movements with its antennæ, imparted to them the
joyful intelligence. It even directed some by accompanying them to the
entrance of this aperture, and these, in their turn, served as guides
to the rest. Every time they met, they stopped and struck each other
with their antennæ in a very remarkable manner, and appeared fully
instructed of the route they should take. In this way, the whole of
this busy group were securely lodged in the same place.
If we could remove an ant at the moment of her discovering a repository
of confectionary, &c. none of her companions would be able to arrive
there; since it is not her traces that conduct them to the spot, she
is under the necessity of returning to the ant-hill and bringing off
her companions.[1] What difficulty has she not in finding her route?
how many times does she not stop in going to, or returning from this
land of promise? She endeavours to discover the places that lay in
her former route; she is seen to halt almost every instant, until she
happens to meet with some visible or palpable clue, as the extremity
of a road, or the base of a wall, which she can follow without
hesitation. Should she fall in with any of her associates from the nest
they put her in the right way by the contact of their antennæ.--This
method of guiding their companions is not practised by every species
of ants; for some employ, under certain circumstances, a process more
mechanical and less rapid than the fugitive signs of which the antennæ
are the organs. This is the subject upon which we shall now touch in
speaking of their migrations.