Ants, it is well known, are fond of sugar, gums and saccharine solutions, as well as the rich juices and tender tissues of animals. But their appetite for sweets is stronger than for all other diets. To them aphis would prove quite as toothsome a morsel as it is to Coccinella, and would be as eagerly hunted for by them were it not for this matter of sweets.
Way back in the history of time, things were perhaps different from what they are now. Aphis was then a racy tidbit, and shared, no doubt, the murderous assaults of Formica, as it did of other carnivores.
For ages this may have been going on, but how long conjecture only can tell. But there came a time when affairs were changed. A new order of things was initiated. Earth was growing better and impressing new features upon its life. An Ant, more wise than any of its fellows, or any that had ever lived before, doubtless stepped upon the scene, and a new era for Aphis inaugurated.
Finding by accident, or otherwise, the delightful qualities of aphis-excretion, it would not be slow to communicate the information to its companions. And as news travels rapidly, and ants are by no means reticent creatures, but a short time would be necessary to carry it everywhere, till all the families, near and remote, of the great world of the Formicidæ would be made acquainted with the important discovery.
Now, as ants are endowed with a high degree of intelligence, considering the position they occupy in the grand scale of created existences, they would soon perceive that their highest good would be attained by taking under their protection the little creatures which are the authors of this excretion. From this time the ants would begin to abandon their sanguinary propensities and manifest some regard for the aphides. The latter, in return, perceiving the former’s friendly disposition, would cease to fear them, and learn to cater to their wants. Thus would be developed, in time, those amicable relations which subsist between the two great, yet widely differentiated, families.
MILCH-COWS OF THE ANTS.
While much has been written upon the social relations subsisting between ants and aphides, yet the subject never grows uninteresting or threadbare. New facts are brought to light as observations widen and extend, some tending to confirm, and others to subvert old notions.
That aphides excrete a sweet, viscid, honey-like fluid, which affords food for many species of ants, has been long known to naturalists. Any one can convince himself of this truth if he will but put himself to the trouble of examining the leaves or branchlets of any plant at the proper season of the year. Scattered upon the foliage and tender twigs thereof will be found millions of aphides, and close beside them countless ants, that ever and anon will be seen to caress, by means of their antennæ, the little creatures for the sweets within their bodies. It has even been asserted that some species of ants keep aphides as human beings do cows, but this by the many has been doubted, or deemed imaginary.
When a young man the writer was disposed to drift with the popular opinion in this particular, but a few facts that fell under his notice whilst searching for carabi and other beetles that live under stones and decayed logs, changed the bias of his mind and established in him the idea that with one species of ant this was at least the case.
It was on an occasion while exploring a neighboring thicket for the objects of his search, that he discovered, underneath a large flat stone which he had raised, a nest of a small red ant, which he took to be the Lasius flavus of the books. The ground was covered all over with pits, and divers communicating roads, and round about were hundreds of ants, larvæ in various stages of development, pupæ and eggs, and innumerous flocks of a white aphis, all of which were being tenderly cared for by a large army of thoughtful nurses.