The inventory of precursory types sees nothing but organic resemblances and disdains the differences of aptitude. By consulting only the bones, the vertebrae, the hair, the nervures of the wings, the joints of the antennae, the imagination may build up any sort of genealogical tree that will fit with our theories of classification, for, when all is said, the animal, in its widest generalization, is represented by a digestive tube. With this common factor, the way lies open to every kind of error. A machine is judged not by this or that train of wheels, but by the nature of the work accomplished. The monumental roasting-jack of a waggoners' inn and a Breguet chronometer both have trains of cogwheels geared in almost a similar fashion. (Louis Breguet (1803-1883), a famous Parisian watchmaker and physicist.--Translator's Note.) Are we to class the two mechanisms together? Shall we forget that the one turns a shoulder of mutton before the hearth, while the other divides time into seconds?
In the same way, the organic scaffolding is dominated from on high by the aptitudes of the animal, especially that superior characteristic, the psychical aptitudes. That the Chimpanzee and the hideous Gorilla possess close resemblances of structure to our own is obvious. But let us for a moment consider their aptitudes. What differences, what a dividing gulf!
Without exalting ourselves as high as the famous reed of which Pascal speaks, that reed which, in its weakness, by the mere fact that it knows itself to be crushed, is superior to the world that crushes it, we may at least ask to be shown, somewhere, an animal making an implement, which will multiply its skill and its strength, or taking possession of fire, the primordial element of progress. (Blaise Pascal(1623-1662). The allusion is to a passage in the philosopher's "Pensees." Pascal describes man as a reed, the weakest thing in nature, but "a thinking reed."--Translator's Note.) Master of implements and of fire! These two aptitudes, simple though they be, characterize man better than the number of his vertebrae and his molars.
You tell us that man, at first a hairy brute, walking on all fours, has risen on his hind-legs and shed his fur; and you complacently demonstrate how the elimination of the hairy pelt was effected. Instead of bolstering up a theory with a handful of fluff gained or lost, it would perhaps be better to settle how the original brute became the possessor of implements and fire. Aptitudes are more important than hair; and you neglect them because it is there that the insurmountable difficulty really resides. See how the great master of evolution hesitates and stammers when he tries, by fair means or foul, to fit instinct into the mould of his formulae. It is not so easy to handle as the colour of the pelt, the length of the tail, the ear that droops or stands erect. Yes, our master well knows that this is where the shoe pinches! Instinct escapes him and brings his theory crumbling to the ground.
Let us return to what the Scoliae teach us on this question, which incidentally touches on our own origin. In conformity with the Darwinian ideas, we have accepted an unknown precursor, who by dint of repeated experiment, adopted as the victuals to be hoarded the larvae of the Scarabaeidae. This precursor, modified by varying circumstances, is supposed to have subdivided herself into ramifications, one of which, digging into vegetable mould and preferring the Cetonia to any other game inhabiting the same heap, became the Two-banded Scolia; another, also addicted to exploring the soil, but selecting the Oryctes, left as its descendant the Garden Scolia; and a third, establishing itself in sandy ground, where it found the Anoxia, was the ancestress of the Interrupted Scolia. To these three ramifications we must beyond a doubt add others which complete the series of the Scolia. As their habits are known to me only by analogy, I confine myself to mentioning them.
The three species at least, therefore, with which I am familiar would appear to be derived from a common precursor. To traverse the distance from the starting-point to the goal, all three have had to contend with difficulties, which are extremely grave if considered one by one and are aggravated even more by this circumstance, that the overcoming of one would lead to nothing unless the others were surmounted as successfully. Success, then, is contingent upon a series of conditions, each one of which offers almost no chance of victory, so that the fulfilment of them all becomes a mathematical absurdity if we are to invoke accident alone.
And, in the first place, how was it that the Scolia of antiquity, having to provide rations for her carnivorous family, adopted for her prey only those larvae which, owing to the concentration of their nervous systems, form so remarkable and so rare an exception in the insect order? What chance would hazard offer her of obtaining this prey, the most suitable of all because the most vulnerable? The chance represented by unity compared with the indefinite number of entomological species. The odds are as one to immensity.
Let us continue. The larva of the Scarabaeid is snapped up underground, for the first time. The victim protests, defends itself after its fashion, coils itself up and presents to the sting on every side a surface on which a wound entails no serious danger. And yet the Wasp, an absolute novice, has to select, for the thrust of its poisoned weapon, one single point, narrowly restricted and hidden in the folds of the larva's body. If she miscalculates, she may be killed: the larva, irritated by the smarting puncture, is strong enough to disembowel her with the tusks of its mandibles. If she escapes the danger, she will nevertheless perish without leaving any offspring, since the necessary provisions will be lacking.
