Fabre, Poet of Science

by Georges Victor Legros

Feeding only upon wheat, a single weevil, the Calendar beetle, produces ten thousand eggs, whence issue as many larvae, each of them devouring its grain.

In all species the number of births is at first exaggerated, for all, the obscure, the nameless, the most destructive, our pests as well as our most precious helpers, have their utility and their part to play in the general scheme of life, a raison d'être in the eternal renewal of things, which is without reference to the vexatious or beneficent quality of their behaviour to us.

Each has its rank assigned, each has its task, to one the flower, to another the roots, to a third the leaves; the vine has its caterpillars, its beetles, its butterflies; the clover, its moths and mites. [(10/6.)]

Man sees himself forced to submit to them, and spends himself in vain efforts to carry on an often useless campaign. Nothing seems to affect them, neither drought, nor rain, nor even the severest cold; and the eggs and larvae, organizations apparently delicate in the extreme, are often more tenacious of life than the adults. Fabre has proved this: let the temperature suddenly fall twenty degrees: the eggs of Geotrupes and the larvae of the cockchafer or the rose-beetle endure such vicissitudes of temperature with impunity; contracted and stiffened into little masses of ice, but not destroyed, they revive in spring no less than the eel fry, the rotifers, or the tardigrades. One can scarcely believe that life still persists in a state of suspense only in these little frozen creatures, whose organization is already so complicated.

Then, of a sudden, the ravagers disappear; more often than not none knows how or why; deliverance is at hand. What indeed would become of the world were nothing to moderate such fecundity?

Again, each species has its trials which appear in time to moderate its surplusage, and Fabre expounds for us, with a stern philosophy, the terrible devices by which this repression is effected.

Each has its appointed enemy, which lives upon it or its offspring, and which in turn becomes the prey of some smaller creature. The gentle itself, "the king of the dead," has its parasites. While it swims in the deliquescence of putrefying flesh a minute Chalcidian perforates its skin with an imperceptible wound, and introduces its terrible eggs, whence in the future will issue larvae which to-morrow will devour the devourers of to‑day.

None exists save to the detriment of others. Everywhere, even in the smallest, we find "an atrocious activity, a cunning brigandage," a savage extermination, which dominates a vast unconscious world of which the final result is the restoration of equilibrium. [(10/7.)] It is only on these antagonisms, on the enemies of our enemies, that we can found any hope of seeing this or that pest disappear. A small Hymenopteron, almost invisible, the Microgaster glomeratus, is entrusted with the destruction of the cabbage caterpillar; the cochineal wages war to the death upon the green-fly; the Ammophila is the predestined murderer of the harvest Noctuela, whose misdeeds in a beetroot country often amount to a disaster. The Odynerus has for its instinctive mission to arrest the excessive multiplication of a lucerne weevil, no less than twenty-four of whose grubs are necessary to rear the offspring of the brigand, and nearly sixty gadflies are sacrificed to the growth of a single Bembex.

Everywhere craft is organized to triumph over force. Around each nest the parasites lie in wait, "atrocious assassins of the child in the cradle, watching at the doors for the favourable occasion to establish their family at the expense of others. The enemy penetrates the most inaccessible fortress; each has its tactics of war, devised with a terrible art. Of the nest and the cocoon of the victim the intruder makes its own nest, its own cocoon, and in the following year, instead of the master of the house, he will emerge from underground as the usurping bandit, the devourer of the inhabitant."

While the cicada is absorbed in laying her eggs an insignificant fly labours to destroy them. How express the calm audacity of this pigmy, following closely after the colossus, step by step; several at once almost under the talons of the giant, which could crush them merely by treading on them? But the cicada respects them, or they would long ago have disappeared." [(10/8.)]