The Birth of Weapons—All Flesh is Grass—Utility and Ornament—The Fever of Love—The “Challenge” of the Deer—What it means—More about “Hormones”—“Hummel” Stags—The Age of Deer—The “Courtship” of the Moose—Types of Antlers—Antlered Females—Fighting Topi—The Lance of the Oryx in the Lion’s Flanks—Happiness and Hartebeestes—Odoriferous Suitors—The Bloody Sweat of the Hippopotamus—The Elephant in Love—Concerning Tusks—Polygamy. From Apes to Antelopes is a far cry, but contrasts are always helpful. Antelopes and Deer, Zebras and Elephants, Rhinoceroses and Swine, are types, taken at random, of that great and important group of animals known as the “Ungulates,” or “Hoofed” animals. These illustrate in a very striking manner what is meant by the term “Secondary Sexual Characters.” They demonstrate no less forcibly what is meant by the term “Sexual Selection.” They are valuable in this connection, because of the often formidable weapons, in the shape of horns and tusks, which so many species have developed during the struggle for mates. But “Sexual Selection” will not explain their origin, and it is difficult, in the present state of our knowledge, to discover any clues which will reveal this. In seeking these there are certain broad aspects of the problem which When the whole of the evidence comes to be surveyed, and not till then, it becomes apparent that this wonderful diversity is the result of complex factors. That the conditions of existence have controlled the results is beyond question; but it is equally certain that these conditions have been merely controlling and not causative. In other words, we must regard each of these different groups or types—Deer, Antelopes, Horses, Elephants, Swine, and so on—as witnesses of what we call “Heredity.” They are so many “Diathetic types.” That is to say, the forms, or individuals, belonging to each type have inherited certain peculiarities in common; they display a “Diathesis” as the doctors call it: an inherent, inborn tendency, or habit of growth, in a definite direction: a tendency which, ever and anon, develops new qualities, takes new directions. And thus it is that we get Oxen—using this term in its widest sense and not in its special sense—Antelopes, Goats and Sheep, for example. These have, among other things, a “diathesis” in the direction of horn production, and each, too, of a different type. What is meant by this apparently mystifying term “diathesis” will perhaps be made clear by taking the case of the Ox and the Sheep. While very different in appearance, these live on precisely similar food; yet no one has any difficulty in But horns, as horns, apart from their “accidents” of curvature and ornament, must certainly be regarded as the product of Sexual selection, for having once started into being those individuals had the best chance of leaving descendants which were best armed. The possession of horns was not necessary to the maintenance of the species; but such armature was essential among the males in securing possession of the females. Other things being equal, the male with the biggest horns wins the prize. Since these are also used as weapons of offence, or rather of defence, in warding off the attacks of beasts of prey, it might be contended that they are as much the product of Natural selection as of Sexual selection. Plate 4. By the courtesy of Rowland, Ward, Ltd. WEAPONS OF OFFENCE. Horns of various types furnish the most conspicuous of the “Secondary Sexual Characters” of the ruminants. In the Deer only are these branched. In the “hollow-horned” ruminants they are either lance-like or more or less spirally curved, or they may form more or less open loops. 1. Black-tailed Deer. 2. Hangul or Kashmir Barasingha Deer. 3. Greater Kudu. 4. Black-buck. 5. Saiga Antelope, remarkable also for its curiously swollen nose. 6. Marco-Polo’s Sheep. [Face page 52. Attention may now profitably be turned to the behaviour of these interesting tribes when under the alluring influences of love. Tradition and the poets have contrived to persuade us As touching the stags. The antlers, as everybody knows, are shed annually, and their renewal entails a very considerable strain on the system. As a consequence, it is necessary that this period of stress should fall after the trial of winter is overpast, and with the genial summer before them. From the end of March, when the old weapons are shed, till July, the masterful males of the community wander at large, seeking seclusion and avoiding all occasion of quarrel; for they are not only defenceless, but threatened with disaster should any accident With some species this desire to go into retreat is more marked than in others. The Red-deer, and the Wapiti, on the one hand, and the Moose on the other, well illustrate this. The two first-named pass the winter in herds, in the case of the Wapiti numbering many thousand individuals; no other species, indeed, is so markedly gregarious. With the advance of the spring, however, all is changed, for the males withdraw from their companions to suffer humiliation in seclusion. As chill October arrives, a striking alteration in their demeanour becomes apparent, at any rate in the case of the older males. The new antlers are now hardened, and the blood supply, which has hitherto been building up the new weapons, is cut off. As a consequence, the “velvet,” which till now has been directly concerned with the growth of the antlers, dies, and peels off the underlying bone. To facilitate this work of cleaning, the animal rubs them, first against the stems of saplings, and, later, against larger trees, and even rocks, till at last they are ready for “battle, murder and sudden death.” The “rutting” season, in short, has commenced. And with the final completion of the antlers other signs of that approaching frenzy, which is soon to establish itself, become apparent. The most striking of these are the swelling of the neck, and a marked increase in the mane thereof; while the voice enlarges its compass enormously, whereby the females, so long neglected, are now feverishly sought for. Plate 5. Photo by G. IF. Wilson Co. Ltd., from “The Living Animals of the World.” MANCHURIAN WAPITI “CALLING.” The “stags” do not begin to call for mate’s until the horns have more or less completely shed their velvet. [Face page 54. The Red-deer, maddened with desire, scours the country, calling as he travels with a loud musical roar, ever and anon impatiently listening for the tremulous response of A male having once succeeded in forming a harem, will commonly contrive to repeat his success year after year, withstanding all comers. But sooner or later his vigour wanes and he is ousted by another and younger male. Not else would the stamina of the race be preserved. It is considered a moot point, however, whether physical strength and sexual potency run at the same pace; After this outburst of sexual activity has spent itself, the various harems, with their lords, amalgamate; all living in peace through the winter. The stags retain their antlers at this season, partly as a protection against predatory enemies, such as wolves, and other large carnivores, which would otherwise play havoc in their ranks, and partly because the cold of winter and scanty fodder would inhibit the growth of new antlers or reduce their size. With the return of spring the dangers of attack are lessened, temperature rises, and food becomes once more plentiful. Then the inevitable disarmament takes place. The Red-deer, though mature at six, does not reach his prime till his eleventh year, and from thence till his fifteenth or sixteenth year is at his best. The hinds mature earlier, and appear to be fertile for a much longer Old stags shed their antlers, it is remarked, earlier than young ones. And this is an advantage to the species, since it prevents premature breeding on the part of sexually precocious but immature males, and limits competition to the adults. What obtains in the case of the Red-deer obtains also with minor variations due to environment, climate, and so on, in the case of all other deer. The life-history of the Wapiti, as might be supposed, differs only in detail from that of the Red-deer. But during the winter they form vast herds, numbering thousands. It may be that in primitive times the Red-deer was no less numerous. But in this country, at any rate, conditions favourable to the maximum development, either in bodily size, or in the massiveness of the antlers, have long since passed away. Even in the Highlands of Scotland the conditions of existence have entirely changed owing to disafforestation. Deer are essentially forest dwellers. But the “deer forests” are such only in name, and for the most part the wild stags of to-day must get what shelter they can from rocks and inequalities of the ground. From this cause, and from the very natural desire of the owners of such “forests” to secure the finest heads in each year, the whole race has deteriorated. How great a change has come over it may be seen by comparing the heads of British Stags with those from German forests, where the Having regard to the fact that hundreds, and in the distant past thousands, of antlers were shed annually, the comparative rarity of these weapons in the haunts of deer excites comment. This is accounted for by the fact that they are greedily eaten by their late owners, apparently, though unconsciously, for the sake of their bone-producing qualities. By way of contrast with the Red-deer and Wapiti, we may take the Moose (Alces machlis), which at no time, and nowhere, attains to large herds. This is explained by the relatively restricted food supply which obtains in the haunts of these creatures. For they frequent the margins of streams, feeding largely on willows and birch. From the shortness of their necks, and the great length of their legs, they cannot crop grass and other short herbage, for unless they kneel they cannot reach the ground. Hence it is obvious that though their geographical range may be wide, their numbers are kept rigidly in check. They would be fewer still but for the fact that, unlike other deer, they glean no small amount of food from the water, wading out to feed upon aquatic vegetation. The roots of water-lilies are especially sought for, and to obtain these the animal will often disappear entirely under water. As a consequence of the limited food supply the Moose lead solitary lives. On the Eastern side of America, where the winter is severe, a few individuals, generally a family party, will “yard up,” or make a fortress for their mutual The rutting season of the bulls begins as soon as the antlers begin to “peel.” What follows is practically a repetition of what has already been related in regard to the Red-deer and Wapiti. And in this connection it is interesting to note that the natives take advantage of the period of desire in the bull to entice him to his death. Generally this is done by imitating the call of the cow in response to the bull’s anxious bellowing. But in Southern Alaska the opposite side of his nature is played upon. This is done by scraping or beating the bushes with the shoulder-blade of a Moose in such a way as to reproduce the sound of a bull cleaning his horns. The very suspicion of a rival enrages him, and, rushing in a blind fury in the direction of the tell-tale sounds, he speedily falls a victim to the trick which has been played him. That the mating period is the most critical, and most searching in the whole life-history there can be no doubt. Every faculty during this time is put to the test, and from the time of sexual maturity until old age is at last attained it is an annual test. Alertness is all important. Other things being equal, success falls most certainly to those individuals with the keenest perception, and quickest interpretation of sight, sound and smell. One is puzzled at what seems a concession of Darwin’s to the Lamarckian theory of the inherited effects of use in this connection. For in discussing the bellowing of the stag in “The Descent of Man,” he remarks that it “does not seem to be of any special service to him, either during courtship or battles, or in any other way. But may we not believe that the frequent use of the voice, under the As touching the less conspicuous secondary sexual characters of Deer more must be said presently. For the moment the antlers must retain our attention. Time was when the Deer lacked these appendages. When they first appeared, in the now extinct species of the Middle Miocene period, they were no more than short prongs. Later, one of the prongs became elongated, and developed short branches or “tines,” which, in succeeding species, became more numerous, while at the same time, with the gradual evolution of more and more species, these antlers assumed new features both in the matter of size and in the character and number of the “tines,” a development which has reached its maximum to-day. But apart from these specific variations, which have given us such types as those of the Roe-deer, Red-deer, Wapiti, Caribou, Moose, Fallow-deer, Sambar, Schombergk’s deer, the strange Milou-deer, Elds-deer and Mule-deer, each species displays a quite remarkable range of variation in regard to its particular type of antler. Nowhere, perhaps, is this more strikingly marked than in the case of the Caribou and Moose. No doubt this feature is due largely to the fact that the horns are shed annually, and that the variations are due, in part at any rate, to temporary environmental conditions, such as food and weather. But these apart, individual peculiarities are constant, reappearing with more or less exactness each year. Plate 6. Photo by Lord Delamere, from “The Living Animals of the World.” GROUP OF BEISA ORYX. The lance-like horns of these animals can be used with deadly effect, even against lions. [Face page 60. In contemplating these facts one asks: What are the underlying factors of this variability? What is the significance of the branching? What end is attained by the annual shedding? That the antlers constitute very effective weapons of offence there can be no doubt, and one is inclined to regard the branching as the outcome of natural selection, on the assumption that branched antlers would be less deadly than lance-like weapons. It would perhaps be tempting to accept this interpretation as all sufficient were it not for the evidence afforded by the hollow-horned ruminants. The Oryx and the Kudu, for example, are lance-bearers, and therefore show conclusively that stags similarly armed might well have continued to survive in spite of the foils which the “tines” provide. Darwin, long since, guardedly suggested that while these weapons primarily served for offensive purposes, their elaborate systems of branching might have been brought about by sexual selection. That is to say, the extreme beauty of the weapons may excite the admiration of the females as well as our own. Granting this, he inferred they might have played an important part in elaborating the branching by constantly displaying a preference to mate with those males possessed of the largest and most branched antlers. But there are many and serious objections to this suggestion, and the most important of all is the fact that the female is allowed no choice in the selection of her lord and master. We can, then, only regard the antlers of deer as another instance of the survival of a “fortuitous” but inherent variation, which survived because, whatever the defects thereof, they Having regard to the fact that so many of the females among the hollow-horned ruminants have acquired horns, it is somewhat remarkable that in the Reindeer alone among the deer are these weapons normally possessed by the female. The gradual transference to the female of features which were originally secondary sexual characters in the male is an occurrence which is met with in every group of animals. In writing “The Infancy of Animals” I gave a number of instances of this kind. But the case of the Reindeer affords a more than usually striking illustration of this curious sequence; and this because rudiments of antlers are to be met with among the females in several different species of Deer to-day. They have been found in the females of both Roe- and Red-deer, though such cases are rarely met with. As a rule this assumption of the male secondary sexual characters by the female occurs only in very aged animals, or as one of the sequelÆ of diseased ovaries and consequent sterility. But at least one instance is on record of a doe Roe-deer which possessed small antlers while pregnant. Thus, then, we gain a further insight into the process by which the female slowly assumes the outward attributes of the male; that is to say, the secondary sexual characters appear first in the male, and as seasonal characters. Sooner or later they become permanently established. By the time they have become firmly fixed in the male, and apparently not till then, they appear in a dilute form during senility, or in consequence of ovarian disease, in the female. Having once started, however, they appear earlier and earlier in the life-history of succeeding generations of females, and at last in the juvenile stages of both sexes. As may be seen in Plate 4, in the form of the horns the typical hollow-horned ruminants present an exceedingly varied range, and one often of great beauty in the matter of curvature. That they serve as formidable weapons of offence was demonstrated during 1912, when, according to the Annual Report of the Government Game Reserves, published by the Pretoria Government, the game warden, Major Stevenson Hamilton, reported of the Antelopes that “many carcases of males of almost all species, killed in single combat with rivals, were found during the mating season, untouched by anything except vultures.” As a rule, however, these animals, like the Sheep and Goats, and their larger relatives the Cattle, seem to avoid a duel to the death. One or two instances as to the general Major Powell Cotton, again, once witnessed an affray between two Beisa Oryx. Here the master bull of the herd was infuriated by the advent of an intruder in his harem. Time after time they dashed at each other, their foreheads meeting with a thud; then, with horns interlocked, they wrestled fiercely; then, separating, they charged again. Yet neither, he remarks, tried to use his lance-points, as they do when cornered by man or beasts of prey. Nevertheless, encounters of a more sanguinary character appear to be by no means rare, for it is no uncommon experience of hunters to kill bulls of this species in which one eye has been burst by a horn-thrust. Another peculiarity of these animals is the extreme thickness of the hide of the neck and withers, which seems to afford a shield against such spear-thrusts during these battles. How powerful is the thrust of these weapons, and how efficiently they can be used, is shown by the fact that lions in making an attack on an old bull are often severely wounded, or even killed. And there are many instances on record of cases where both the lion and his intended victim have died together, the Antelope having been unable to withdraw his horns from his adversary’s body. The beautiful Pala Antelope fights furiously with rival rams, and the vanquished, as with so many of the Antelopes, form herds by themselves, till one by one they gather strength and skill enough to establish their right to mate. Plate 7. Photo by courtesy of the Duchess of Bedford, Woburn Abbey. ELAND COWS. Among antelopes the females commonly bear horns, which may be even longer than in the males, though less massive. [Face page 64. Plate 8. Photo by courtesy of the Duchess of Bedford, Woburn Abbey. AMERICAN BISON The “Secondary Sexual Characters” of the male are here conspicuously developed, and are seen in the massive fore-quarters and enormous head. The Elands present some puzzling features, for both sexes bear large horns, and they are very massive in the bulls. Yet these animals are generally described as the most inoffensive of all the horned ruminants. That the horns are used to any extent in conflicts between rival males seems doubtful, inasmuch as this species is remarkable for the development of an enormous “dewlap,” a thin pendulous fold of skin which runs from the throat to the chest. Such a form of “ornament”—for in this light we must regard it—would be dangerous, indeed, when much fighting was to be done. Nevertheless, it would be contrary to all our experience to conclude that weapons so well developed as are the horns of the bull Eland were entirely useless. This is a matter which decidedly calls for further investigation. That our knowledge of that most important period of life of the larger mammals, the period of sexual exaltation, is lamentably incomplete will be realized by anyone who seeks enlightenment on this subject. Most of the meagre information we possess has been collected by travellers and sportsmen, neither of whom have the time to devote to the long and laborious watches that a fuller history demands. Every now and then a glimpse is afforded of this period of the life-history which brings home in a very convincing fashion, how little is really known. It seems certain that the fighting hitherto described is to be regarded as but a phase of a cycle of events which takes place at this time. Thus, for example, the old naturalist and traveller Schweinfurth tells how he once encountered a herd of Hartebeest which were apparently effervescing with animal spirits, for they kept running around in It cannot be supposed that these quaint performances are peculiar to the species in which they have been observed, but rather it may be inferred that similar antics, besides others yet to be discovered, are performed by all. Their purpose seems plain enough, for they must be regarded surely as aphrodisiacs, excitants to pairing. They recall the erotic dances of savages, or the ceremonial orgies of ancient civilizations. Such performances, on an even more elaborate scale, are to be met with among the birds. So far, in describing the horned ruminants, the horns only have been considered; but these animals display yet other secondary sexual characters, which, while less conspicuous, are yet no less important during this critical period of life. Some, as for instance the canine teeth possessed by some of the deer, are decidedly puzzling. While absent, or vestigial, in most, in a few they are greatly developed, and this, too, in species which possess relatively large horns, as in the Muntjac. It seems difficult to believe that the co-existence of these very different kinds of weapons can be of The armoury necessary for successful love-making contains yet other weapons, evolved to supplement physical force, and more subtle in their effect. Such are certain skin glands which, at the rutting season, secrete a copious flow of a creamy, or semi-fluid matter, and pungent odour. In the deer the more important of these are found in the deep pit, or “larmier,” which opens in front of the eye. In the Musk-deer, however, this secretion has a most powerful odour of musk, and is formed in a pouch, or “pod,” of about the size of a small orange, under the skin of the abdomen. The secretion, which is formed by the male only, is of a chocolate colour, and of about the consistence of moist gingerbread. It has a most pungent scent, and when diluted forms the basis of many of our most powerful and most highly-prized perfumes, on which account, it may be mentioned, this animal has for generations been submitted to a most unrelenting persecution. But that is another story. In most of the antelopes the principal scent gland is seated in a pit in front of the eye, as in the deer. In some, as in the Gnu, it forms instead a swollen, tumid area, oblong in shape, instead of lying in a pit. In the Reedbuck it is placed around the bases of the horns; and in That scent among the antelopes holds a really important place is shown by the fact that the bull of the common Eland intensifies his natural odours by micturating upon the mass of long hair which grows upon the forehead. To do this the head is bent down and turned tailwards, in order that the tuft should receive its due urinary spray! And goats in captivity exhibit the same curious habit. In them, indeed, it is often pushed to such an excess that blindness results, so that the animal has to be slaughtered. While in many cases these odours are imperceptible to human nostrils, in others this is far from being the case. Among the ruminants the goat is particularly odorous. So also are the giraffe and the water-buck, It is probable that the “bloody sweat,” which at times covers the hide of the Hippopotamus just after leaving the water, is associated with the period of rut. This mysterious exudation is accompanied by small crystals; but though red in colour, it contains no blood. So far no reasonable explanation for this remarkable phenomenon has ever been given, but probably it will be found to be associated with the sexual activities and is possibly odoriferous. A precisely similar exudation occurs in the neck of the male of the Red Kangaroo. That these secretions play an important and perhaps variable part in the selection of mates seems demonstrated in the case of an incident related to me by my friend Mr. John Cooke, who some time ago was watching a flock of some three hundred sheep while it was being driven by the shepherd and his dogs into a field. As soon as they were securely shut in, and the shepherd had gone, three rams who were included in the flock at once began a three-cornered Our survey of the “hoofed” animals has so far been confined to the ruminants. Space must now be found for a brief review of what obtains under like circumstances in the case of the great pachyderms—the Elephant, Rhinoceros and Hippopotamus; the Pig and the Camel. Plate 9. Photo by Lord Delamere, from “The Living Animals of the World” ELEPHANTS. The sexes differ but little in general appearance: and chiefly in the superior size of the male and his more massive tusks. [Face page 70. As to actual “courtship” among these animals practically nothing is known; but the varied and formidable weapons which they possess are enough to show that the secondary sexual characters play a very important part in the preliminary capture of mates. That they may also be used for the more prosaic purpose of securing food is nothing to the point. In the Elephant, for example, the tusks are sometimes of enormous size and weight, specimens of eleven feet in length and weighing as much as two hundred and fifty pounds are on record. They are used for cutting through the bark of machabel trees, which is then seized by the trunk and torn off, for elephants are extremely fond of this bark; and they are Superficial secondary sexual characters are wanting both in the Hippopotamus and the Camel. Both, however, possess a formidable armature of teeth which are capable of inflicting very severe wounds. In the Hippopotamus the canines are of enormous size, and their punishing power is further strengthened by the fact that they work in opposition to a pair of similar teeth in the lower The Swine, which are near relations of the Hippopotamus, in like manner develop huge pointed canines, and these reach their maximum in the great Wart-hogs of Africa. But in the swine the mechanism differs, for although the canines are closely opposed, the shaft of the upper teeth curves upwards, and the lower teeth are much smaller than the upper. In fighting, these animals do not bite, like the Hippopotamus, but use the upper canines to rip up their antagonist with a sudden, swift upward and sideways movement of the head. How dangerous is the wound thus inflicted those who have hunted the wild-boar know well. A curious exaggeration of this arrangement of the teeth is seen in the Babiroussa. Herein the upper canines grow directly upwards, actually piercing the upper lip as in the case of the downwardly growing tusks of the elephant. That these teeth, however, are of any service in fighting is doubtful, for the upper tooth curves upwards and backwards in a semicircle so that the points are harmless. The tusks of the lower jaw, however, are extremely long and pointed, though their wounding power is limited by reason of the upper teeth. This may account for the fact that Plate 10. HEAD OF MALE WART-HOG. In the “Swine” family the canine teeth are always greatly developed, but they attain to their maximum, relatively, in the Wart-hog. Photos by Scholastic Photo Co., from “The Living Animals of the World.” MALE AND FEMALE BABIRUSA. A characteristic of this pig is the peculiar development of the tusks in the male, the upper pair of which grow through the lips and curve upwards. [Face page 72. Plate 11. Photo by Lord Delamere, from “The Living Animals of the World.” SOMALI ZEBRAS. The Zebras, unlike their cloven-hoofed relations, have no weapons, save for inter-tribal conflicts. Yet they have been as successful in holding their own against lions and other predatory animals as species provided with horns. [Face page 72 Plate 12. Photo copyright by A. H. Bishop. GIRAFFE. The horns of this animal can prove formidable weapons of offence on occasion, though they are useless against predatory animals. While the ungulates, or hoofed animals, are peculiar in the development of horns as weapons of offence, they are by no means singular in the use of teeth for this purpose. In some cases, as in the Muntjac, both forms of armature are present. The only other instances where teeth in this group of animals are used for offensive purposes are those furnished by the Camel and the Horse. But here they do not exhibit that excessive size which is met with in the Elephant, and some of the Swine. In both the Camel and the Horse it is the canine which is used, and both jaws are similarly armed. Since the camel has no upper incisors, the part played by the teeth is beyond dispute; but it has been contended that the horse uses his incisor or “front-teeth” alone when fighting. But this is not so; the canines can, and do, inflict ugly wounds, as is shown by the necks of zebras. A further method of defence among the larger Ungulates, at any rate, is resorted to when hard pressed: and this is the use of the hoof in kicking. Giraffes kick both after the usual fashion and in striking downwards with the fore-foot. And an interesting demonstration of this has been furnished by Mr. F. C. Selous in his delightful “African Nature Notes.” He relates that on one occasion he came across a calf only a day or two old, with its back broken. It is not difficult to account for the origin of such secondary sexual characters as manes, beards, tusks, and brightly-coloured areas of skin, though whether our interpretations are really correct is another matter. But no attempt to explain the origin of horns has yet achieved a like degree of persuasiveness. These weapons appear only in the Ungulates, a group which has, in past times, given birth to some very extraordinary types of head armature of this kind. These must be excluded from the present discussion; suffice it to say that, as usual, they were the adjuncts of the males. According to current theories it is supposed that these weapons arose as the result of the action of sexual selection. It is assumed that the hornless ancestors of now horned ruminants fought for their mates by “butting” with the forehead. Naturally, other things being equal, the thickest skulled combatants obtained the mastery. Any tendency to develop frontal “bosses” of bone would further enhance the chances of success, and would, indeed, The formidable horns of the Rhinoceros are of a totally different character, being solid structures formed by hairlike agglomerations, firmly fixed upon a roughened area of the nasal region. These weapons play a very important part in settling disputes between rival males, but on other occasions demanding offensive tactics the Indian Rhinoceros at any rate seems to depend rather on his power of wounding by means of the chisel-shaped lower incisors. These, by means of a swift lateral movement of the head can be made to inflict most terrible gashes, as those who hunt with elephants well know. It is quite possible, however, that the teeth are also thus used during struggles for supremacy. And this may perhaps account for the enormous bucklers of skin developed by the Indian Rhinoceros, but only indicated in the case of the African species. All the larger Ungulates, and many of the smaller species, are polygamous. The Rhinoceros, and all of the swine-group save the Hippopotamus, among the larger species are exceptions to the rule. The preponderance of females which this implies is generally supposed to be due to the losses sustained among the males by fighting during the struggle for mates. The case of horses, however, seems to militate against this view, for though they undoubtedly fight furiously, no evidence is forthcoming Were it possible to secure the necessary data it would probably be found that polygamy, and polyandry, are determined solely by the numerical proportions of the sexes: the excess of males or females being due neither to “Natural” nor “Sexual” Selection, but to inherent peculiarities of the germ-plasm tending to produce an excess of males, or females, as the case may be. Finally, all the evidence goes to show that it is a mistake to suppose that polygamy is due to the excessive sexual avidness of the males, which impels them to first essay the overthrow of all possible rivals, and then to appropriate every female within their sphere of influence, holding them by force. On the contrary, this plurality of mates is thrust upon them. And this because the females, impelled by “mate-hunger,” attach themselves to the nearest male within call: the size of the harem depending on the number of available males. The battles which are fought between rival males are no more sanguinary than in the case of monogamous species. This contention is well illustrated by the African Wydah-birds (Vidua), which are markedly polygamous, though they have no special weapons of offence. In districts where males are numerous the harem will not exceed eight, or ten, females; where males are scarce this number may be increased to fifty. In like manner the varying number of hinds accompanying a stag are to be regarded, not as an index of his prowess, but of the scarcity or abundance of males in the neighbourhood. |