I could give many more examples of reptile parents whose family habits are more or less singular. There are the little-known “Cœcilians,”[20] the strange, snakelike amphibians of S.E. Asia and Ceylon; where the mother, with her limbless body, yet contrives to dig a nursery for her eggs, which she jealously guards. I should like to write of the families of the newts and salamanders, among whom the young are never completely abandoned, and whose parental habits present many features of interest. But to tell their life stories with all the vivid facts would take more space than I can allow to this one chapter of my book; and to give a bald record of their habits would afford little interest. I must, however, recount two instances of marked solicitude for the family, shown in each case by a different parent. Take the case of a mother’s care first. A captive mother-salamander, of the species known as Oregon plethodon, was placed with her eggs in a jar. She at once took possession of them, forming a loop around them with her tail. But, displeased with this unfamiliar house, she moved the eggs repeatedly from place to place till at length she was satisfied, and all the time using her tail for the work of transportation as a kind of maternal arm. In the second case the father most faithfully guards the eggs. A giant salamander in the Zoological Gardens of Amsterdam kept watch over a clump of his wife’s eggs for a period of ten weeks. This careful father was seen every now and then to crawl among the eggs and lift them up, apparently for the purpose of aerating them.
From the foregoing examples it may, I think, be taken as established that among the reptiles there are many exemplary fathers. If the question is asked as to why in some species the care of the young is undertaken by the father and in others by the mother, I can only answer that I do not know. It would seem almost that at this early stage of life Nature was making experiments as to which was the better parent. I would suggest that possibly such a reversal of the family duties was started by chance, possibly by the loss of the mother, or even by a specially energetic father, and on being found successful the arrangement was continued and became fixed as a habit. I have not sufficient knowledge to know if this is possible. At any rate, it appears to be plain that, where for any reason the family duties are neglected by the mother, and where the maintenance of the species demands protection being given to the young, the father steps in to take the place of the mother; and by his care and devotion he becomes a truly constituent part—a working member—of the family group. I would ask you to keep this fixed in your attention, as I shall have to refer again and again to this fact that is here suggested.
What obtains among reptiles with regard to the father’s care for the young is even more frequent among fish-fathers. The common stickleback of our ponds and streams affords an admirable illustration of intelligent and devoted fatherhood. In this species the rôle of the two sexes is completely reversed; when once the eggs are deposited by the mother, the whole task of guarding them is undertaken by the father. His labours begin with the construction of a nest. This is formed of bits of weed, of fibre and dirt, collected with much care, the whole being held together by a cement produced by the clever father out of a secretion from his kidneys. Having prepared the nursery, the stickleback sets out to find a wife heavy with eggs. His love choice apparently is decided by the capability of his spouse for her maternal function. By means of much persuasion and passionate courtship he woos her and induces her to deposit her burden of eggs in his nest.
I must wait to impress upon you the wonder of this fact. These love-antics of the stickleback, which are unique among fishes, would seem not to be exercised for the gratification of male desire, but for the purpose of inducing the female to lay her eggs,—to do her part in giving him offspring. Vainly do I ask myself the reason of this quite unusual sexual altruism. This is very extraordinary. The father woos the reluctant mother with passionate dances and his glad excitement is apparently intense. At this season the stickleback is transformed and glows with brilliant colours, his scales make silver look dim, his throat glows with flaming vermilion, he literally puts on a wedding garment of love.[21] And did I not fear being tedious by again waiting to point a moral, I should ask attention to this further proof given by the stickleback’s love joys to the truth which stands out in these life histories of pre-human parents. I mean this: the parent—the mother or the father—lives in the offspring. You will see how deep is the truth here. The parent is, after all, only the transitory custodian of the undying gift of life.
The conduct of the mother stickleback is in sharp contrast with the devotion of the stickleback father. At once, having rid herself of her eggs, her desire would seem to be to escape any further responsibilities. She forces her way out of the nest by wriggling through the wall opposite the entrance. True, by doing this she renders a service to the nursery, as she thereby furnishes a channel through which a continuous supply of fresh, cool water can be driven, thus keeping the eggs bathed. This is the only work the stickleback mother does for the family. The male, after the first laying, may persuade her to add still further to the deposit of eggs. Sometimes, wearied with her one effort, she refuses. Thus forced, the stickleback seeks a second wife, driven into polygamous conduct through his desire for offspring. I know of no other case that is parallel with this. And the stickleback’s action has often been misrepresented. He is instanced as a polygamist; such is the fate that ever awaits self-sacrifice!
When the nest is full the father stickleback mounts guard over the entrance of the nursery for nearly a month, and he watches by day and by night, defending his precious charge against all comers.
And here another curious fact must be noted: the most dangerous assailants to the safety of the nursery are his own wives; these unnatural mothers would, if they were permitted, devour every single egg. Is it this conduct of the female sticklebacks that explains the devotion of the male? Again I do not know. Certain it is, however, that the safety and care of the young is the stickleback father’s constant occupation—the duty to which he sacrifices his life. From time to time he changes the position of the eggs; he is a master in sanitation and keeps them constantly bathed with fresh water. This he does by driving a stream through the nest by means of a fanning motion of his breast, fins and tail. Through all the hatching period he works with unceasing care.
When at length the fry are born, the father’s vigilance is even further taxed. The children, vigorous and venturesome, have to be watched by day and by night and protected. Around and across and in every direction the father, as guardsman, continually swims. He drives off all comers with splendid courage. On one occasion a stickleback father was watched while his nest was attacked by two tench and a golden carp; he seized their fins and struck with all his might at their heads and eyes. Truly the stickleback’s care of his children is extraordinary. His vigilant eye is everywhere. If any members of the young brood stray too far from the nest for safety, he immediately swims after them, seizes them in his mouth, and brings them back to the safe playwater in the vicinity of the nursery. This continuous watchfulness lasts for about six days after the hatching.[22]
Well, what do you think now of the common view of the parental instinct being stronger always in the mother than in the father? Have we not been taking too much for granted and accepting theory for truth? In the light of our knowledge gained from these examples of the father’s extreme devotion, it seems impossible to refrain from thinking that the most intelligent and fit parent is the one who cares for the young. No doubt it is difficult, or even impossible, to decide the circumstances that have contributed to this strange result of the father taking the mother’s place in the family. We do not know whether these acts of his sacrifice to the children’s welfare imply the presence of the mind element—that is, whether they can be regarded as conscious as distinguished from unconscious adaptation, but this is altogether a separate matter and has nothing to do with the question we are considering.
Fish display, according to Romanes,[23] emotions of fear, pugnacity, social, sexual and parental feelings, anger, jealousy, play and curiosity. Such emotions, he states, correspond with those that are distinctive of the psychology of a child of about four months.