Polygamy would be explained by the rarity of males; which is not the case with most mammals, among whom the males are almost constantly more numerous. Buffon was the first to note this predominance, neither has he nor has anyone since, given a satisfactory explanation. People have said that in man, at least, the elder parent gives the sex to the offspring, and the more surely as the difference in age is greater, but, by this reckoning one would have almost nothing but males. People have also said that the younger the woman, the more likely the child to be male. The early marriages of the past are supposed to have yielded more males than the late marriages of the present. None of these statements is serious. What remains past doubt is that European humanity, to consider only that, gives an excess of males. The general average is about 105, with extremes of 101 in Russia, and 113 in Greece; the French average is the same as the general average. One has not been able to make out, in these variations, either influence of race, or of climate, or of taxes, or of nationality, or anything else in particular. There are more male humans, more male sheep: it is a fact, which being regular, will be difficult to explain.
We find here superabundance, there penury of males, but neither does the abundance determine the customs, nor is it likely the lack of males would do so. There are so few males among gnats that Fabre was the first to recognize them, the proportion about one male to ten females. This in no way produces polygamy, for the male dies the instant after coupling. Nine out of ten gnat females die virgin, and even without having seen a male, without knowing that males exist: perhaps celibacy augments their ferocity, for it is the female gnat and she alone who sucks our gore. One supposes also that female spiders outnumber the males ten or twenty to one: perhaps the buck who has escaped the jaws of one mistress has the courage to risk his life yet again? It is possible, the male spider who survives his amours may live on for several years. Polygamy seems to exist, and in its most refined form, with one sort of spider, the ctenize, whose males are peculiarly rare. The female digs a nest in the earth, into which the male descends; he lives there some time, then he leaves, comes back: there are several houses between which he divides his time equitably.
The polygamy of a curious little fish, the stickleback, is of the same sort, although more naive. The male builds a grass nest, then goes in search of a female, brings her back to the nest, invites her to lay; scarcely has his first companion departed when he brings in another. He only stops when there is a satisfactory treasure of eggs, then he fecundates them in the usual manner. Thence on he guards the nest against malefactors, and watches the hatching. In the odd reversal of rôles, the young recognize their father; their mother may be the fish passing between them, or the one gliding off like a shadow, or the one chewing a grass blade. When the stickleback world becomes reasonable, that is to say absurd, it will perhaps give itself up to the "recherche de la maternité"? Their philosophers will demand "Why should the father alone be charged with the education of his offspring?" Up to the present one knows nothing except that he educates them with joy and affection. Among sticklebacks and among men there is no answer to such question save the answer given by facts. One might as well ask why humanity is not hermaphrodite, like the snails, who strictly divide the pleasures and burdens of love, for all snails commit the male act, and all lay. Why has the female ovaries, and the male testicles: and this flower pistils, and this one stamens? One ends in baby-talk. The wish to correct nature is unnecessary. It is hard enough to understand her, even a little, as she is. When she wishes to establish the absolute responsibility of the father, she establishes the strict couple, and especially, absolute polygamy. The pigeon is no longer certain of being the father of his young; the cock can not doubt it, he being the sole male among all his hens. But nature has no secondary intentions, she keeps watch that, temporary or durable, fugitive or permanent the couples are fecund; that is all.
Gallinaceæ and web-feet present certain birds best known and most useful to us. They are nearly all polygamous. The cock needs about a dozen hens, he can do with a much larger number, but in that case his ardour wears itself out. The duck, very licentious, is accused of sodomy. Not only is he polygamous, but anything will serve him. He might better be a natural example of promiscuity. A gander is good for ten or twelve geese, the cock-pheasant for eight or ten hens. The lyrure tetras needs many more, he leads a sultan's harem behind him. At dawn, in the season of amours, the male starts whistling with a noise like steel on a grindstone, simultaneously stretching himself up, and spreading the fan of his tail, opening and puffing his wings. When the sun clears the horizon he rejoins his females, dances before them, while they devour him with their eyes, then he mounts them, according to his caprice, and with great vivacity.
Polygamy is the rule among herbivora; bulls, bucks, stallions, bison are made to reign over a troop of females. Domesticity changes their permanent polygamy into successive polygamy. Stags go from female to female without tying up to any; the females follow this example. A specie immediately akin gives, on the contrary, an example of the couple; the roebuck and his doe live in family, and bring up their young until these are ready to mate. The male of a certain Asian antelope needs more than a hundred docile females. Naturally, these harems can only be formed by the destruction of other males. This hundred females represents possibly more than a hundred males put out of business, males being always the more numerous sex, among mammals. The utility of such hecatombs to the race is not certain. Doubtless one may suppose that the surviving male is the strongest, or one of the strongest of his generation, that is the lucky element, but whatever his vigour it may be expected to wane at some point or other before a hundred females desiring satisfaction. Some females are forgotten, others fecundated in moments of weariness: for a certain number of good products, there are a number of mediocre creations. True, these are destined, if male, to perish in future combats; but if they are female, and if they receive the favours of the chief, this system might have for consequence the progressive degradation of the specie. It is however, probable that the necessary equilibrium is re-established; combats between females, combats of coquetry, incitements of femininity, doubtless take place, and it is the triumph of the malest male and of the most female females.
Virey asserts, in Déterville's "Nouveau dictionnaire d'histoire naturelle," that the greater polygamous apes get on very well with women indigenes. It is possible, but no product has ever been born of these aberrations, which we must leave to theological works on bestialitas. Men and women, even of the Aryan race have at times set out to prove the radical animality of the human specie by the peculiarity of their tastes. The interest in these matters is chiefly psychological, and if one can draw no proof of evolution from the chance relations between woman and dog, man and goat, the coupling of primates of different orders offers no evidence either. There is however a relation between man and apes, it is that they are both divisible into polygamists and monogamists, at least temporary; but this does not differentiate them from most other animal species.
In most human races there is a radical polygamy, dissimulated under a show-front of monogamy. Here generalizations are no longer possible, the individual emerges and with his fantasy upsets all observations, and annihilates all statistics. The monogamist's brother is polygamous. A woman has known only one man, and her mother was every one's fancy. One may assert the universal custom of marriage and deduce monogamy as a conclusion, and this will be false or true according to the epoch, milieu, race, moral tendencies of the moment. Moral codes are essentially unstable, since they represent only a hand-book ideal of happiness; morality will modify itself according to the mobility of this ideal.
Physiologically, monogamy is in no way required by the normal conditions of human life. Children? If the father's help is necessary it can be exercised over the children of several women as well as over those of one woman only. The duration of tutelage among civilized people is, moreover, excessive; it is dragged out, when it is a matter of certain careers, almost until ripe age. Normally puberty ought to liberate the young human, as it liberates the young of other mammals. The couple need then last only ten or fifteen years; but female fecundity accumulates children at a year's interval, so that, as long as the father's virility lasts, there might be, always one feeble creature having right to demand protection. Human polygamy could then, never be successive polygamy, save by exception, that is, if man were an obedient animal, submitting to normal sexual rules, and always fecund; but this successivity is frequent and divorce has legalized it. The other and true polygamy, polygamy actual, temporary or permanent, is still less rare among people of European civilization, but nearly always secret and never legal; it has for corollary a polyandry exercised under the same conditions. This sort of polygamy is very different from that of Mormons, Turks, gallinaceæ and antelopes, it is nothing more than promiscuity. It does not dissolve the couple, in diminishing its tyranny it renders it more desirable. Nothing so favours marriage, and consequently, social stability, as the de facto indulgence in temporary polygamy. The Romans well understood this, and legalized concubinage. One can not here deal with a question so remote from, natural questions. To condense one's answer into briefest possible space, one would say that man, and principally civilized man, is vowed to the couple, but he only endures it on condition that he may leave and return to it at will. This solution seems to conciliate his contradictory tastes, and is more elegant than the one offered by divorce, which is always the same thing over again; it is in conformity not only with human, but also with animal tendencies. It is favourable to the species, in assuring the suitable up-bringing of children, and also to the complete satisfaction of a need, which, in a state of civilization is inseparable either from æsthetic pleasure or sentimental pleasure.
[1] That is to say in the eye of some imaginary divinity who might be supposed to regard humanity, or even the slower mammals from a timeless or say five century altitude.—Translator's note.
[2] One believes nevertheless that the male bat suckles one of the two young that the couple regularly produces. But these animals are so odd and so heteroclite that this example, if it is authentic, would not be a decisive argument.