C.D. Warner, et al., comp. The Library of the World’s Best Literature.
An Anthology in Thirty Volumes. 1917.
The Habits of Ants
By Sir John Lubbock (1834–1913)
T
It is evident, therefore, that the ants of each community all recognize one another, which is very remarkable. But more than this, I several times divided a nest into two halves, and found that even after a separation of a year and nine months they recognized one another, and were perfectly friendly; while they at once attacked ants from a different nest, although of the same species.
It has been suggested that the ants of each nest have some sign or password by which they recognize one another. To test this I made some insensible. First I tried chloroform; but this was fatal to them, and … I did not consider the test satisfactory. I decided therefore to intoxicate them. This was less easy than I had expected. None of my ants would voluntarily degrade themselves by getting drunk. However, I got over the difficulty by putting them into whisky for a few moments. I took fifty specimens,—twenty-five from one nest and twenty-five from another,—made them dead drunk, marked each with a spot of paint, and put them on a table close to where other ants from one of the nests were feeding. The table was surrounded as usual with a moat of water to prevent them from straying. The ants which were feeding soon noticed those which I had made drunk. They seemed quite astonished to find their comrades in such a disgraceful condition, and as much at a loss to know what to do with their drunkards as we are. After a while, however, to cut my story short, they carried them all away; the strangers they took to the edge of the moat and dropped into the water, while they bore their friends home into the nest, where by degrees they slept off the effects of the spirit. Thus it is evident that they know their friends even when incapable of giving any sign or password.
This little experiment also shows that they help comrades in distress. If a wolf or a rook be ill or injured, we are told that it is driven away or even killed by its comrades. Not so with ants. For instance, in one of my nests an unfortunate ant, in emerging from the chrysalis skin, injured her legs so much that she lay on her back quite helpless. For three months, however, she was carefully fed and tended by the other ants. In another case an ant in the same manner had injured her antennæ. I watched her also carefully to see what would happen. For some days she did not leave the nest. At last one day she ventured outside, and after a while met a stranger ant of the same species, but belonging to another nest, by whom she was at once attacked. I tried to separate them; but whether by her enemy, or perhaps by my well-meant but clumsy kindness, she was evidently much hurt, and lay helplessly on her side. Several other ants passed her without taking any notice; but soon one came up, examined her carefully with her antennæ, and carried her off tenderly to the nest. No one, I think, who saw it could have denied to that ant one attribute of humanity, the quality of kindness.
The existence of such communities as those of ants or bees implies, no doubt, some power of communication; but the amount is still a matter of doubt. It is well known that if one bee or ant discovers a store of food, others soon find their way to it. This, however, does not prove much. It makes all the difference whether they are brought or sent. If they merely accompany on her return a companion who has brought a store of food, it does not imply much. To test this, therefore, I made several experiments. For instance, one cold day my ants were almost all in their nests. One only was out hunting, and about six feet from home. I took a dead bluebottle fly, pinned it on to a piece of cork, and put it down just in front of her. She at once tried to carry off the fly, but to her surprise found it immovable. She tugged and tugged, first one way and then another, for about twenty minutes, and then went straight off to the nest. During that time not a single ant had come out; in fact, she was the only ant of that nest out at the time. She went straight in; but in a few seconds—less than half a minute—came out again with no less than twelve friends, who trooped off with her, and eventually tore up the dead fly, carrying it off in triumph.
Now the first ant took nothing home with her; she must therefore somehow have made her friends understand that she had found some food, and wanted them to come and help her to secure it. In all such cases, however, so far as my experience goes, the ants brought their friends; and some of my experiments indicated that they are unable to send them.
Certain species of ants, again, make slaves of others, as Huber first observed. If a colony of the slave-making ants is changing the nest,—a matter which is left to the discretion of the slaves,—the latter carry their mistresses to their new home. Again, if I uncovered one of my nests of the fuscous ant (Formica fusca), they all began running about in search of some place of refuge. If now I covered over one small part of the nest, after a while some ant discovered it. In such a case, however, the brave little insect never remained there; she came out in search of her friends, and the first one she met she took up in her jaws, threw over her shoulder (their way of carrying friends), and took into the covered part; then both came out again, found two more friends and brought them in, the same manœuvre being repeated until the whole community was in a place of safety. This, I think, says much for their public spirit; but seems to prove that—in F. fusca at least—the powers of communication are but limited.
One kind of slave-making ant has become so completely dependent on their slaves, that even if provided with food they will die of hunger, unless there is a slave to put it into their mouth. I found, however, that they would thrive very well if supplied with a slave for an hour or so once a week to clean and feed them.
But in many cases the community does not consist of ants only. They have domestic animals; and indeed it is not going too far to say that they have domesticated more animals than we have. Of these the most important are aphides. Some species keep aphides on trees and bushes, others collect root-feeding aphides into their nests. They serve as cows to the ants, which feed on the honey-dew secreted by the aphides. Not only, moreover, do the ants protect the aphides themselves, but collect their eggs in autumn and tend them carefully through the winter, ready for the next spring. Many other insects are also domesticated by ants; and some of them, from living constantly underground, have completely lost their eyes and become quite blind.
But I must not let myself be carried away by this fascinating subject, which I have treated more at length in another work. I will only say that though their intelligence is no doubt limited, still I do not think that any one who has studied the life history of ants can draw any fundamental line of separation between instinct and reason.
When we see a community of ants working together in perfect harmony, it is impossible not to ask ourselves how far they are mere exquisite automatons, how far they are conscious beings. When we watch an ant-hill tenanted by thousands of industrious inhabitants, excavating chambers, forming tunnels, making roads, guarding their home, gathering food, feeding the young, tending their domestic animals,—each one fulfilling its duties industriously, and without confusion,—it is difficult altogether to deny to them the gift of reason; and all our recent observations tend to confirm the opinion that their mental powers differ from those of men not so much in kind as in degree.