CHAP. IX. FURTHER INFORMATION ON THE AMAZON ANTS.

If any proof were still wanting of the origin of auxiliary ants in mixed ant-hills, the discovery of other habitations of this kind would, doubtless, throw much light upon this subject. I had not long been occupied, before I discovered such, in which the Amazons were the same, but the auxiliaries different, being of that species denominated Mining Ants.

The Mining Ants (Fourmi mineuse), who build after the manner of Negro Ants (of which I have already treated in the chapter on architecture), are a little larger than the latter, from which they also differ in the colour of the breast, which is of a bright red. The feet and antennæ are also of a reddish cast; in regard to the rest of the body, there is a close resemblance: but for the real distinction between these two species, we must look to their character. The Mining Ants possess great vivacity, are very courageous, and live upon animal food. The Negro Ants are, on the other hand, timid and pacific. It was not, therefore, without astonishment, that I saw, for the first time, an ant-hill, composed of Legionary and Mining Ants; it was at least thrice the size of the simple Miner ant-hills, and contained a vast number of inhabitants of the two casts. Among the individuals of this society, the same kind of intelligence seemed to reign as among those which had fallen under my previous notice.

The Mining Ants go forth in a crowd, from morning until evening, for the purpose of foraging in the neighbourhood, and thus providing for the wants of the colony: on their return they share the fruits of their industry with the Amazons, who are as idle in this community, as in that of compound Negro ant-hills. The Mining Ants, moreover, are alone employed in establishing a new domicile, and transporting thither the Rufescent Ants, their pupæ, their larvæ, and the rest of the colony, whenever they wish to change their abode; in a word, they are equally excellent labourers as the Negro Ants, and display much more zeal in defending their nest.

If compound ant-hills owe their existence to the pillage of the pupæ, the object of the Amazon Ants in their excursions would be, to attack the dwelling of Mining Ants, when their associates were of that cast, and of Negro Ants when they lived with ants of that species.

In the neighbourhood of the mixed ant-hill of which I have just spoken, comprising a circumference of more than fifty paces, there was no habitation of Negro Ants: but, of the Miner ant-hills there was great abundance. This, therefore, was a sufficient reason for believing, that the ants of that species, living with the Amazons, drew their origin from these several colonies. To be assured of this, I visited a compound Miner ant-hill, between four and five in the evening, a time when the army usually commences its march: the Amazons were already assembled on the nest, and ready to set forth; they proceeded like a torrent along a deep dyke, and marched in a more compact body than ordinary. In a short time they reached the nest they proposed to attack, which was inhabited by Mining Ants. As soon as the Legionaries began entering the subterranean city, the Miners rushed out in crowds, and whilst some fell upon the invaders with great spirit, others passed through the scene of contest, solely occupied in bearing off to a place of safety their larvæ and pupæ. The surface of the nest was for some time the theatre of war. The Legionaries were often despoiled of the pupæ they had seized by the Miners, who darted upon them with amazing spirit, fighting body to body, and disputing the ground with an exasperation I had never before witnessed. The Amazon army was, notwithstanding successful, and recommenced its march in good order, laden with pupæ and larvæ: instead, however, of proceeding in file, it now maintained close rank, forming a compact mass, a precaution the more necessary, as the courageous insects upon whom they had made this attack, hastened in pursuit, and even harassed them, to within ten paces of their citadel.

During these combats the pillaged ant-hill presented, in miniature, the spectacle of a besieged city: hundreds of its inhabitants were observed to quit it, carrying here and there the pupæ, larvæ, and young females they were anxious to preserve from the fury of their enemies. The major part mounted the neighbouring plants, bearing the young between their teeth; others deposited them under the thick bushes. When the danger was entirely gone by, they brought them back into the city, and barricaded the gates, near which they posted themselves in great number to guard the entrance. All was calm, however, in the mixed ant-hill; the Amazons had entered quietly their abode, and had been received by the auxiliary ants as the real proprietors.

Immediately after, the Legionaries again departed, and proceeded towards a Miner ant-hill of considerable extent, considering themselves in sufficient force to cope with the guardians of that habitation: they threw themselves en masse upon one of the galleries indifferently guarded; but their number not permitting them to enter all at once, the Mining Ants that were without, immediately precipitated themselves upon the invaders: and whilst they were engaged in desperate combat, their fellow-citizens in considerable number, losing, perhaps, every hope of defending their abode, and the little ones confided to their care, left the nest with the pupæ, larvæ, and youngest ants, took flight in every direction, and literally covered the ground to a considerable distance. The contest became every moment warmer: here the Amazons were endeavouring to seize the pupæ, which the Miners were removing from the seat of war; there the besieged were observed to wrest from the conquerors the fruit of their rapine. Confusion was at its height; Legionaries and Miners attacked each other impetuously, and often in the excess of their fury, deceived as to their object, fell upon their companions, whom, however, they immediately released. This commotion was confined to the rear-guard of the Legionary army; the main body, richly freighted, left the devastated city, and forming into square battalion, retraced their steps to their own citadel, constantly assailed by the Miners, who, for some time, continued the pursuit. It is only by their address, the rapidity of their movements, and the use of their sting, that the Legionaries are enabled to disengage themselves. I have often remarked, during these combats, the females of the Miners take flight, bearing off the pupæ in their mouths, acting in this respect like simple workers; but have never known them to take any share in defence of their nest. The pillage and skirmishes are not of long continuance; for in less than a quarter of an hour, we find the Amazons on the road to their garrison. Notwithstanding the courage and exasperated state of both parties, but a trifling number of ants perish.⁠[1]⁠

This scene, brilliant for its extent, was renewed as often as the Amazons found the temperature friendly to their departure. The purloined pupæ are soon developed: and not knowing their real family, (like the Negro Ants in mixed ant-hills,) bestow all their care upon the offspring of the Amazons.

Here then are two distinct species of auxiliary ants, in whose form and character we trace no resemblance, affording a favourable opportunity for solving the question, relative to the composition of these ant-hills. If in compound Negro ant-hills, and in compound Miner ant-hills, we find males and females of but one species, we must, of course, conclude, they have no relation to the auxiliary ants, but only to the Amazons; indeed those which I saw carried on several occasions by the Mining workers, in their emigration from one nest to another, in every respect resembled the little males and large females, met with in mixed Negro ant-hills: and I have looked in vain for others in the same habitation. I have even been present at the time of their leaving their abode, and can affirm, notwithstanding researches the most assiduous, attention the most unwearied, I never yet perceived any which were not in every respect like those I have described. Their departure and the circumstances attending it is by no means a point of indifference. For several successive days they come to the surface of the nest, surrounded by the Mining Ants, who form their escort, and take the same care of them as the workers in simple ant-hills, of the males and females of their own species. At length they quit the nest and commence their aërial excursions.

On the 31st July, at half-past ten in the morning, I saw several little black males issue from a compound Negro ant-hill, accompanied by a considerable number of Negro Ant labourers. The number of males were continually increasing; several Amazons on this occasion also left the nest, and came among them, although it was to them an unaccustomed hour; they approached the males and licked them after the manner of the Negro Ants. At length the large females came forth from the citadel, climbed the neighbouring plants, and in their turn received from the Negro Ants and the Amazons, the same attention as the males. At eleven o’clock the males became extremely restless, ran against and overturned each other, beat the air with their wings, and finally finished their gambols by taking flight. The females followed their example. More than fifty females, and four times as many males, quitted the nest. I kept guard for some time thinking they would return; but I never saw them more.

The appearance of this ant-hill was both satisfactory and pleasing; the contrast of females of a fine yellow colour, with little males entirely black; of winged insects with neuters destitute of wings; and of Amazon labourers, living in friendly union with such a number of Ash-coloured Ants, presented a picture full of interest, notwithstanding the trifling size of the objects that composed it.

In compound ant-hills I have now and then observed some very remarkable individuals which may be seen delineated in Pl. 2. fig. 1. These are Rufescent Ants, equalling, in size, females of the same species, differing only in the form of their thorax, which is not enlarged, and destined to bear wings; it resembles that of the labourers. These individuals are, from their size, classed with females, but they do not possess wings. I should have assigned them a place among the labourers, had I ever seen them take part in their excursions.⁠[2] Here then is another example of those transitions we have remarked between the females and labourers of some insects of the same genus. Among bees there are several modifications of queens; there exist, also, among humble bees fecund labourers of different degrees of size, resembling, in almost every respect, females. This fact comes in support of those already given, and must convince us, that females and labourers are originally of the same order, and do not owe their form and real character, but to the more or less complete developement of their organs. I know not if the individuals, of which I have just spoken, are capable of laying, nor can I state the purport of their creation; be this as it may, they are extremely rare, and have no relation with the Ash-coloured and Mining Ants, in mixed ant-hills, where we equally find them.

Let us now return to the winged females. A little time after quitting their natal abode, they lose their wings like the ants of other species, traverse the ground, and seek a place of shelter. I could have wished it were possible to follow them; for their history, especially that part of it which relates to their new progeny, strongly excited my curiosity. To ascertain how these several colonies exist on their first formation, is a task of extreme difficulty: how, at this period, can they associate themselves with auxiliary ants, not being in sufficient force to make the necessary incursions to procure them? How, under these circumstances, do they act or can they do without them? Not being able to answer these questions, I shall adduce some proofs, showing that the Amazons are more skilful in the domestic arts than idlers, or those habituated to a life of ease.

Monsieur Latreille, more fortunate than myself, found one of these newly formed ant-hills. After giving a description of the Rufescent Ant, (of which we have been accustomed to speak under the name of Legionary or Amazon Ant,) he observes, “This species is exceedingly rare; I never observed it in society but once, and this society consisted only of a few members. It runs remarkably quick, and makes its nest, I believe, in the earth.” Had there been any association with the auxiliary ants, this careful observer would doubtless have noticed and been much struck with it.⁠[3] I look upon it, therefore, as an almost certain fact, that the Rufescent Ants, before they are accustomed to the services of the Ash-coloured and Mining Ants, can put in use faculties which lie dormant when they become associated with these auxiliaries. It even happens they will sometimes assume their office, that is, change parts with them: a fact of which I have been once, and once only, a witness.

A compound ant-hill was established a short time since, on the terrace of the house in which I resided. I carefully observed the excursions of the Amazons, and one day remarked, they directed their route to a deserted ant-hill: the ants who had previously occupied it, pillaged doubtless too often by their so much dreaded neighbours, had taken the precaution of decamping with arms and baggage. The Amazons, who were perhaps badly lodged, profited by this circumstance. After having visited it, they returned, took up in their mouths the Negro Ants of the mixed ant-hill, and transported them to the new habitation. This operation lasted some hours, and the emigration was completely effected in this manner.

In this instance I saw the inverse of what I had hitherto observed, but never experienced the gratification of witnessing a repetition. The Amazons carried the Ash-coloured Ants as the latter usually carry them. The whole colony being transferred to the new lodging, they there rested, and each species again returned to their ordinary duties.

We see, from this example, that it is highly probable the Amazons know more than they would seem to know; and if we have seen them perish of hunger rather than take the trouble of providing for themselves, we must attribute it to the custom of their receiving nourishment immediately from the Ash-coloured Ants, and never going themselves in search of it.

Those who live in small numbers with their maternal parent, not being as yet accustomed to an idle life, do not, probably, confine themselves to the sole occupation of war, but engage in domestic duties; for during a certain period, the ant-hill is entirely composed of Amazons. But when their number shall have given them confidence, they are then seen to sally forth to procure the pupæ of the Ash-coloured and Mining Ants; which, under their management, become auxiliaries and useful companions. These are only conjectures, and perhaps very distant from the truth. I know, however, of none more plausible to explain the formation of new Amazon ant-hills.

As to the preservation of compound ant-hills, I believe it consists, as in all other ant-hills, in reserving some pregnant females to keep up the population. I have often seen in these habitations, and in all seasons, females destitute of wings. I opened, in the middle of April, some of these dwellings, where I found a considerable number of eggs, agglutinated together, assiduously guarded by Negro Ants. I also noticed some Amazon females, surrounded by the same guardians. They inhabited the most elevated part of the building, and the eggs were collected near them. In the month of June I first perceived the male pupæ in their enveloping membrane; their larvæ being in the number of those that spin: the female pupæ were rather later in appearing. They were liberated from their envelope, by the Negro labourers, in the same manner as the pupæ of Ash-coloured and Mining Ants, a little time before their last transformation. It is only in the month of July they pass into that state which puts them in a condition for flying. The pupæ of the Amazon Labourers were at that time very numerous in all their nests, but I no longer found there the pupæ of Ash-coloured and Mining Ants. The pupæ which the Legionaries had purloined the preceding year, were developed before autumn; their last invasions occurring in September. These warrior ants have only two months and a half to collect all the pupæ of which they stand in need. The temperature is often sufficiently high in May and the beginning of June to allow of their departure; they do not, however, venture abroad until their males are on the point of undergoing their transformation: they sometimes leave the nest individually, and are then always stopped by the Negroes, who bring them back to the ant-hill. I know not from what motive this conduct on the part of the auxiliaries arises; I have often remarked it, and it is a certain fact, that the Legionaries never go to pillage before that period. If they began earlier to purloin the larvæ and pupæ belonging to the Negro Ants, they would make great booty; it would, however, be in a great degree composed of the pupæ of males and females, and these it seems, they are not permitted to seize. Nature, aware of the serious inconveniencies that would arise from an attack made at this time by the Amazons, particularly guards against it, by producing the males and females of those ant-hills destined to pillage at a much earlier period than the males and females of the martial ants, and in not permitting the latter to be engaged in acts of rapine, until the metamorphosis of the winged insects has taken place.

The Ash-coloured and Mining Ants, are to be considered then as the negroes of the Amazons; it is from among them the latter procure slaves; they kidnap them at an age when their instinct is not developed; and these insects, on being brought up by the Amazons, divide with them the fruit of their industry. Can we sufficiently admire the prudence and wisdom these insects display in the establishment of such an institution! We here trace neither servitude nor oppression, nor do the ants themselves, taken from perhaps twenty different dwellings, entertain the slightest suspicion of their being in a foreign nest: they live under the same roof in brotherly and sisterly union, and if they regard the Amazons, it is but to show them greater attention. Nature, profound in her combinations, seems fully aware that old ants would never live sociably with those of another species, but that young ants may, especially if they have been accustomed in early life to see and receive from them some attention. She seems, also, aware, that no aversion is excited in the breasts of those who witness their birth. It is in this way, she has instituted mixed or compound ant-hills: it is on this account the Amazons in their expeditions never carry off adult ants, only larvæ and pupæ; for the same reason, they never seek the destruction of their enemies, their only aim being to steal from them their little ones.

An important truth relative to the moral condition of these insects, rests upon these facts—that their instinct is capable of receiving several modifications. Ants, carried away in their youth, may become familiar, and even live with an hostile species; it is in the first period of their life those impressions are formed which they always preserve. The very same objects that would naturally have excited their hatred, now only inspire them with a sentiment of love.