LITMIR.BIZ

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An elaborate instinctive capacity is probably the result of adding on one contrivance after another to a simpler common habit. And this is surely the same as saying that these little creatures have the power of learning through experience. A beginning of the instinct of caring for the young is exhibited when the mother insect chooses a favourable food position wherein to lay the eggs. Nor is it difficult to imagine how this maternal forethought may have grown out of an earlier habit, for it is but a step, though a great one, from collecting food for self—an instinct that may be traced back and back—to the habit of providing and collecting food for others. Then, this instinct of caring for the future being strongly fixed, it, in some cases and under certain favourable conditions, leads on and on to the specialised maternity and climax of parental sacrifice and devotion, such as may be illustrated by the admirable scarabees, or dung-beetles, of the Mediterranean region and elsewhere.

      I have given one case of perfect parents, the Minotaurus Typhæus; but I wish to review such conduct more fully. The family qualities of the dung-beetles are so devoted and so striking, they will repay our study.

      The late M. Fabre describes in his inimitable way the nursery which makes the centre and life of the scarabees’ home. These dung-workers edify us with their morals. Both sexes co-operate in making the burrows which serve as a larder for food and a nursery for the young. They are cavities dug in soft earth, usually in sand, shallow in form, about the size of one’s fist, and communicating with the outside by a short channel just large enough for the passage of the balls of dung-food. Both parents work with equal zeal to found a household. “The father is the purveyor of victuals and the person entrusted with the carrying away of rubbish. Alone, at different hours of the day he flings out of doors the earth thrown up by the mother’s excavations; alone he explores the vicinity of the home at night in quest of the pellets whereof his sons’ loaves shall be kneaded.

      “A most careful choice of material is undertaken, and often the devoted husband and father is compelled to search long and far for pellets freshly dropped, for whereas coarse bread crammed with bits of hay is good enough for his own and his wife’s food, he is always more careful where the children are concerned. Legful by legful, with slow and most patient labour, the material is heaped up and rolled into a ball. Then the food-ball has to be carried to the burrow; no easy task. Even then the father’s labours are not ended; on reaching the burrow, it is his work to shred the dung-food into flour, which he pours down to the mother for her to knead into the children’s bread. Finally, when the last task is accomplished, the dung-father goes out alone to die. He has gallantly performed his duty as a paterfamilias; he has spent himself without stint to secure the prosperity of his kith and kin.”

      The devotion of the dung-father is equalled by that of the dung-mother. More skilled than her spouse in domestic matters, she is occupied always in the home, where she works in the lower floor of the burrow, which she has prepared for the nursery. Here she kneads and forms the cylindrical loaves in which the eggs are placed. In some cases she does more, and we find several species of the dung-mothers anticipating the suckling of the young, the supreme expression of maternal solicitude. These mothers chew the dung-food, and out of it prepare a frothy pap or cream, with which they cover the walls of the nest to form a special first meal for the emerging grub. Throughout her working life the dung-mother never leaves the home. It should be noted that her family is always a very small one: does this, perhaps, explain the parental devotion? From the first fortnight in May, when the eggs are laid, the mother mounts guard over her children. Never does she eat herself, as she will not touch the food prepared and needed for them. She watches through the long months until the coming of the autumn rains in September. Then, when the day of release comes at last, she returns to the surface, accompanied by her family. At once her children leave her; unmindful of her devotion, they go off to find food and begin life for themselves. Thereupon, having nothing left to do, she dies, and ends her sacrifice.[14]

      Before I leave this fascinating record of the dung-beetle parents, space must be found wherein to note further certain of their characteristics and habits, which are of special interest to my inquiry as they would appear to be directly connected with the highly developed family qualities of these insects. Fabre tells us that there is no outward difference between the two sexes among the dung-beetles. I call attention to this fact, which I am not able to explain. The scarabees are among the most beautiful of all insects, and the female and male share the same glory. It is my belief that the secondary sexual characters are directly dependent on the occupational activities of the species, as also on the form of union or marriage which pertains and the strength of the parental emotions. Thus, when the male and the female are equally devoted to each other and to the family and its care, many cases among these pre-human parents seem to prove that such devotion and occupational union tends to lessen the ornamental sexual differences in the secondary physical characters. This is a question of profound interest, and demands more attention than it has yet received.

      The second fact is of even greater importance to us. The form of union or marriage common among the dung-beetles would appear to be an unusually strict monogamy. These insects, as we have seen, associate in couples, and there is strong evidence that the male remains faithful to his spouse. Such admirable conduct is the more remarkable when we remember that the mother is held in the nursery by her duties during the greater period of the marriage; and meantime the father has to wander far in search of food, making frequent excursions outside the home, but he resists the temptations to which these outings are likely to lead, and always he returns to the home, where he wears himself out for his family.

      To test the strength of this conjugal fidelity Fabre made an experiment with the dung-beetles of whose habits I have before spoken, the Minotaurus Typhæus. He placed two couples of these beetles in an enclosed space, marking one of the couples. He allowed them to begin the making of their burrows or homes, then he separated the couples and destroyed the half-made burrows. Once, twice, and a third time he did this, causing confusion among these peaceful workers. But on each occasion the couples came together in the same order; the right male and female knew each other, and, taking little notice of the tumult, each time again they began their work of home-making.

      Five more times Fabre separated them and broke up their homes. The result I will give in Fabre’s own beautiful words—

      “Things are now spoilt, sometimes each of the four that are experimented on settles apart, sometimes the same burrow contains the two males or the two females, sometimes the same crypt the two sexes, but differently associated from what they were at first. I have abused my powers of repetition. Henceforth disorder reigns. My daily shufflings have demoralised the burrowers, a crumbling home always requiring to be begun afresh has put an end to lawful associations. Respectable married life becomes impossible from the moment when the house falls in from day to day.”

      I have now said enough, I think, to show that at many different levels in the insect kingdom the parental instinct is already developed. Pre-eminent in virtue is the behaviour of the dung-beetle parents. And this is all the more interesting as it proves how closely related good parenthood is with the conditions of the home and the form of marriage.

      A few more words may here be added to what has been said already concerning the influence of intelligence on instinct. It is a difficult question, but, speaking roughly, intelligence may be said to act in two opposite ways; that is, it may aid both in the making and the unmaking of instincts.[15] Thus the dung-beetles frequently change their conduct, and they do this by modifying their instincts through intelligent adaptation. It is scarcely too much to say that with them intelligence reaches its highest form of originality. Why is this? Fabre gives us the answer. “The more the maternal instinct asserts itself, the higher does instinct ascend.”

      It would be better probably if the word instinct were used in a more restricted sense: it should not be regarded as being able to explain everything. This mysterious impulse is held to direct all pre-human parents in their conduct to their young. Very well; but what of the directing force behind? The evidence is strong that even the lowliest creatures have their own problems, and are able to solve them. Can we explain otherwise the wide difference in conduct between parent and parent? Do we know what it is that gives a special direction to the instinctive activities in the accomplishment of a design greater than any of these parents know? We cannot answer fully. But instinct

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