The Life and Love of the Insect

by Jean-Henri Fabre

When the house-owner ascends, the other draws back a little, just enough to leave a free passage and no more. Why should she put herself out? The meeting is so peaceful that, short of further information, one would not suspect the presence face to face of a destroyer and destroyed. Far from being intimidated by the sudden arrival of the Halictus, the Gnat pays hardly any attention; and, in the same way, the Halictus takes no notice of her persecutress, unless the bandit pursue her and worry her on the wing. Then, with a sudden bend, the Hymenopteron makes off.

The parasite of the Halictus is in a difficult position. The homing Bee has her booty of honey in her crop and her harvest of flour on the brushes of her legs: the first is inaccessible to the thief; the second is in the form of powder and devoid of stable support. And even then it is quite insufficient. To collect the wherewithal to knead the round loaf, the journeys have to be repeated. When the necessary amount is obtained, the Halictus will pound it with the tip of her mandibles and shape it with her feet into a globule. The Dipteron’s egg, were it present among the materials, would certainly be in danger during this manipulation.

The alien egg, therefore, must be laid on the made bread; and, as the preparation takes place underground, the parasite is under the forced necessity of going down to the Halictus. With inconceivable daring, she does go down, even when the Bee is there. Whether through cowardice or foolish indulgence, the dispossessed insect lets the other have its way.

The object of the Gnat, with her tenacious lying-in-wait and her reckless burglaries, is not to feed herself at the harvester’s expense: she could find the wherewithal to live [[205]]on in the flowers, with much less trouble than her thieving trade involves. The most, I think, that she can allow herself to do in the Halictus’ cellars is demurely to taste the victuals, in order to ascertain their quality. Her great, her sole business is to settle her family. The stolen goods are not for herself, but for her sons.

Let us dig up the pollen-loaves. We shall find them most often crumbled with no regard to economy, simply abandoned to waste. We shall see two or three maggots, with pointed mouths, moving in the yellow flour scattered over the floor of the cell. These are the Dipteron’s progeny. With them we sometimes find the lawful owner, the worm of the Halictus, but stunted and emaciated with fasting. His gluttonous companions, without otherwise molesting him, deprive him of the best of everything. The wretched starveling dwindles, shrivels and disappears with little delay. His corpse, a mere atom, blended with the remaining provisions, supplies the maggots with one mouthful the more.

And what does the mother Halictus do in this disaster? She is free to visit her grubs at any moment; she has but to put her head into the passage of the house: she cannot fail to be apprised of their distress. The squandered loaf, the disorder of swarming vermin are events easily recognized. Why does she not take the intruders by the skin of the belly? To crush them with a bite of her mandibles, to fling them out of doors were the business of a second. And the foolish creature never thinks of it, leaves the famishers in peace!

She does worse. When the time of the nymphosis comes, the Halictus mother goes to the cells rifled by the parasite and closes them with an earthen plug as carefully as she does the rest. This final barricade, an excellent [[206]]precaution when the box is occupied by an Halictus in course of metamorphosis, becomes a screaming absurdity when the Dipteron has passed that way. Instinct does not hesitate in the face of this incongruity: it seals up emptiness. I say, emptiness, because the crafty maggot hastens to decamp the instant that the victuals are consumed, as though it foresaw an insuperable obstacle for the coming Fly: it quits the cell before the Hymenopteron closes it.

To rascally guile the parasite adds prudence. All, until there is none of them left, abandon the clay homes which would be their undoing, once the entrance was plugged up. The earthy retreat, so grateful to the tender skin, thanks to its polished coating, so free from humidity, thanks to its waterproof glaze, ought, one would think, to make an excellent waiting-place. The maggots will have none of it. Lest they should find themselves walled in when they become frail Gnats, they go away and disperse in the neighbourhood of the ascending pit.

My digging operations, in fact, always reveal the pupæ outside the cells, never inside. I find them enshrined, one by one, in the body of the clayey earth, in a narrow niche which the emigrant worm has contrived to make for itself. Next spring, when the hour comes for leaving, the adult insect has but to creep through the rubbish, which is easy work.

Another and no less imperative reason compels this change of abode on the parasite’s part. In July, a second generation of the Halictus is procreated. The Dipteron, reduced, on her side, to a single brood, remains in the pupa state and awaits the spring of the following year before effecting her transformation. The honey-gatherer resumes her work in the natal hamlet; she avails herself [[207]]of the pits and cells constructed in the spring, saving no little time thereby. The whole elaborate structure has remained in good condition. It needs but a few repairs to make the old house habitable.