LITMIR.BIZ

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life. But a species is maintained sometimes by the prodigality of production and sometimes by the expenditure of care and sacrifice on the part of the parents. And here we find again a lesson waiting for us to learn. For it is hardly necessary to point out that the same facts are true of human births; just as the family is unregulated or considered, do we find waste and many births with parental neglect in the first case and restricted births with parental devotion in the second. There seem to be no problems of the family that these pre-human parents have not had to face and solve.

      But to return.

      “The celebrated Midwife toad (Alytes obstetricans) gives us a further delightful example of the father nursing the young. The mother-toad lays her eggs attached to one another by threads so that they form a long chain. The father-toad then twines this chaplet of his wife’s eggs round and round his thighs. He has the strange appearance, it has been said, of a gentleman of the court of the time of James I, arrayed in puffed breeches. His devotion is very complete. After having encumbered himself with the coming family, he retreats to a hole in the ground. Here he stays with admirable patience by day, stealing forth at night to feed, and to bathe his egg-burdened legs in dew or, when possible, in water. When his period of service is past and the young are ready for quitting the eggs, he seeks the water. Here before long the young burst forth and swim away, whereupon the father, now free from his family duties, makes himself tidy (cleans himself of the remains of the eggs) and resumes his normal appearance.”

      With some frogs, as, for example, in certain S. American and African species, the parents take up the burden of caring for the young only after they have reached the tadpole stage. The German naturalist Brauer recently found in the Seychelles islands a small frog (Arthroleptis Seychellensis) undertaking the guardianship of the young family. An adult frog (it is not stated whether it was the father or the mother) was carrying nine tadpoles on its back, to which they were attached by a sucker on the belly. Unfortunately, little is known of the habits of these frogs. It is believed that the eggs are laid in some shallow pool, and that later one or other parent returns to the nursery to take up the care of the young tadpoles.

      A further remarkable case of care exercised by the father is that of Darwin’s frog, the Rhinoderma darwini, where the eggs are guarded in a great pouch under the throat, and opening by two slits into the mouth. During the courtship this pouch is used as a voice organ to charm the female, with sharp ringing notes like a bell. But the love-calls end with the birth of the family. There is now serious work to be accomplished. The father takes his wife’s eggs into his pouch, which now enlarges and extends backwards under the belly to the groin, and upwards on each side almost to the backbone. In the warm chamber thus formed, the tadpoles live until they become young frogs. They then make their way up through the doorways into their father’s mouth, and from that living nursery they swim out into the wide world.

      Well, what can we say of this case? We have heard of some animal fathers eating their progeny, but here the father’s mouth is turned into the hatching nursery. Did I not tell you we should find very much to astonish us?

      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

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