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CHAPTER VII

THE INDUSTRIES OF ANIMALS

1. Hunting—2. Shepherding—3. Storing—4. Making of Homes 5. Movements

It is likely that primitive man fed almost wholly upon fruits. His early struggles with animals were defensive rather than aggressive, though with growing strength he would become able for more than parrying. We can fancy how a band of men who had pursued and slain some ravaging wild beast would satisfy at once hunger and rage by eating the warm flesh. Somehow, we know, hunting became an habitual art. We can also fancy how hunters who had slain a mother animal kept her young alive and reared them. In this or in some other way the custom of domesticating animals began, and men became shepherds. And as the hunter's pursuits were partially replaced by pastoral life, so the latter became in some regions accessory to the labours of agriculture, with the development of which we may reasonably associate the foundation of stable homesteads. Around these primary occupations arose the various human industries, with division of labour between man and woman, and between man and

man.

These human industries suggest a convenient arrangement for those practised by animals. For here again there are hunters and fishers-beasts of prey of all kinds-pursuing the chase with diverse degrees of art; shepherds, too, for some ants use the aphides as cows; and farmers without doubt,

if we use the word in a sense wide enough to include those who collect, modify, and store the various fruits of the earth.

In illustrating these industries, I shall follow a charming volume by Frédéric Houssay, Les Industries des Animaux, Paris, 1890.

1. Hunting. Of this primary activity there are many kinds. The crocodile lies in wait by the water's edge, the python hangs like a lian from the tree, the octopus lurks in a nook among the rocks, and the ant-lion (Myrmeleon) digs in the sand a pitfall for unwary insects. The angler-fish (Lophius piscatorius) is somewhat protectively coloured as he lies on the sand among the seaweeds; on his back three filaments dangle, and possibly suggest worms to curious little fishes, which, venturing near, are engulfed by the angler's horrid maw, and firmly gripped by jaws with backward-bending teeth. Many animals prowl about in search of easy prey—eggs of birds, sleeping beasts, and small creatures like white ants; others would be burglars, like the Death's Head Moth (Sphinx atropos) who seeks to slink into the homes of the bees; others are full of wiles, witness the cunning fox and the wide-awake crow. Many, however, are hunters by open profession, notably the carnivorous birds and mammals. If these hunters could speak we should hear of many strange exploits; such, for instance, as that of a large spider which landed a small fish. The ins and outs of their ways are most interesting, especially to the student of comparative intelligence. Think of the Indian Toxotes, a fish which squirts drops of water on insects and brings them down most effectively; several birds which let shells drop from a height, e.g. the Greek eagle (Gypaëtos barbatus), which killed Æschylus by letting a tortoise drop on his head; the grey-shrike (Lanius excubitor), which spikes its victims. on thorns; and, strangest perhaps, the slave-making expeditions of the Amazon ants. All strength and wiles notwithstanding, the chase is often by no means easy; the hare grows swift as well as the fox, many grow cautious like trout in a much-fished stream, scouts and sentinels

are often utilised, the weak combine against the strong, and the victims of even the strong carnivores often show fight valiantly.

2. Shepherding.—Although the ants are the only animals which show a pastoral habit in any perfection, and that only in four or five species (e.g. Lasius niger and Lasius brunneus), I think that the fact is one about which we may profitably exercise our minds. I shall follow Espinas's

admirable discussion of the subject.

We may begin with the simple association of ants and aphides as commensals eating at the same bountiful table. But as ants discovered that the aphides were overflowing with sweetness, they formed the habit of licking them, the aphides submitting with passive enjoyment. Moreover, as

the ants nesting near the foot of a tree covered with aphides would resent that others should invade their preserves, it is not surprising to find that they should continue their earthen tunnels up the stem and branches, and should eventually build an aerial stable for some of their cattle. Thither also they transport some of their own larvæ to be sunned, and as they carried these back again when the rain fell, they would surely not require the assistance of an abstract idea to prompt them to take some aphides also downstairs. Or perhaps it is enough to suppose that the aphides, by no means objecting to the ants' attentions, did not require any coaxing to descend the tunnels, and eventually to live in the cellars of the nests, where they feed comfortably on roots, and are sheltered from the bad weather of autumn. In autumn the aphides lay eggs in the cellars to which they have been brought by force or coaxing or otherwise, and these eggs the ants take care of, putting them in safe cradles, licking them as tenderly as they do those of their own kind. Thus the domestication of aphides by ants is completed.

Now what is the theory of this shepherding? (1) We have no warrant for saying that the ants have deliberately domesticated these aphides, as men have occasionally added to the number of their domesticated animals. It does not seem to me probable that even primitive man

was very deliberate in the steps which led to the first domestications. (2) Nor is it likely that the process began in a casual way, and that it became predominant in four or five species in the course of natural selection. For the habit is more a luxury than a necessity, and it is not likely to have been evolved before the establishment of the sterile caste of workers, who have no means of transmitting their experience. Moreover, initial steps are always difficult to explain on this theory. (3) The theory which seems to me warrantable is that the habit arose by a gradual extension of habits previously established, that it was neither deliberate nor casual in its origin, but a natural growth, beginning neither in a clever experiment nor in a fortunate mistake of an individual worker ant, but the outcome of the community's progressive development in "intellectual somnambulism," helped in some measure by the sluggish habits of the aphides. And, if you wish, the formula may be added, "which was justified in the course of natural selection."

3. Storing. Not a few animals hide their prey or their gatherings, and with marvellous memory for localities return to them after a short time. But genuine storing for a more distant future is illustrated by the squirrels, which hide their treasures like misers. Many mice and other rodents do likewise, and in some cases the habit seems to become a sort of craze, so large are the supplies laid in against the winter's scarcity. Very quaint are the sacred scarabees (Ateucus sacer), which roll balls of dung to their holes, and sometimes collect supplies at which they gnaw for a couple of weeks. Some ants (e.g. Atta barbara) accumulate stores of grain, occasionally large enough to be worth robbing; and there is no doubt that they are able to keep the seeds from germinating for a considerable time, while they stop the germination after it has begun by gnawing off plumule and radicle and drying the seeds afresh. Dr. M'Cook's account of the agricultural ant of Texas (Pogomyrmex barbatus) gives even more marvellous illustrations of farming habits, for these ants to a certain extent at least cultivate in front of their nests a kind of grass with a rice

like seed. They cut off all other plants from their fields, and thus their crops flourish.

But animals store for their offspring as well as for themselves. The habit is very characteristic of insects, and is the more interesting because the parents in many cases do not survive to see the rewards of their industry. Sometimes, indeed, there is no industry, for the stores of other insects may be utilised. Thus a little beetle (Sitaris muralis) enters the nest of a bee (Anthophora pilifera) and lays its eggs in the cells full of honey. More laudable are the burying-beetles (Necrophorus), which unite in harmonious labour to bury the body of a mouse or a bird, which serves as a resting-place for their eggs and as a larder for the larvæ. The Sphex wasp makes burrows, in which there are many chambers. Each chamber contains an egg, and is also a larder, in which three or four crickets or other insects, paralysed by a sting in the nervous system, remain alive as fresh meat for the Sphex larva when that is hatched. After the Sphex has caught and stung its cricket and brought it to the burrow, it enters at first alone, apparently to see if all is right within. That this is thoroughly habitual is evident from Fabre's experiment. While the Sphex was in the burrow, he stole away the paralysed cricket, and restored it after a little; yet the wasp always reconnoitred afresh, though the trick was played forty times in succession. Yet when he substituted an unparalysed cricket for the paralysed one, the Sphex did not at once perceive what was amiss, but soon awoke to the gravity of the situation, and made a fierce onslaught on the recalcitrant victim. So it is not wholly the slave of habit.

4. Making of Homes.-Houssay arranges the dwellings of animals in three sets. (a) those which are hollowed out in the earth or in wood; (b) those which are constructed of light materials often woven together; and (c) those which are built of clay or similar material. We may compare these to the caves, wigwams, and buildings in which men find homes.

Burrows are simplest, but they may be complex in

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