of course errs in attributing, in his ignorance of Protective, Warning, and other colours, all the hues of birds and butterflies to this agency. But it is probable that whenever colours and other ornaments do not serve for purposes of protection (as e.g. the lion’s mane and the horns of beetles, vide Tropical Nature, p. 202), they serve the purpose of sexual recognition of species. A case cited by Darwin to prove that quadrupeds take notice of colour, is very suggestive in this connection: “A female zebra would not admit the addresses of a male ass until he was painted so as to resemble a zebra, and then, as John Hunter remarks, she received him very readily.”
It is probable, therefore, that in many cases the unique spots and stripes and colours of animals subserve the special use of facilitating the finding of a partner; and in this way they relate directly to the courtship and Romantic Love of animals. Thus we see how the Love affairs of animals may indirectly affect their Personal Beauty in a way quite different from that suggested by Darwin.
LOVE-CHARMS AND LOVE-CALLS
The same reasoning applies to the music of animals, vocal and instrumental, on which Darwin lays great stress. In his opinion, the music of some male animals serves to charm the females æsthetically, and thus gives to the best musicians special advantages through Sexual Selection. But the instances cited by him hardly warrant this conclusion, and seem rather to point to the inference that the function of animal music is chiefly to facilitate courtship, by making it easy for the females to discover the whereabouts of a male of the same species. The evidence tends to show that it is not the male whose voice is most mellow and melodious that catches the female, but rather the one who is most vigorous and persistent and has the loudest organ. As Jaques says in As You Like It: “Sing it: ’tis no matter how it be in tune, so it make noise enough!”
Darwin himself quotes a naturalist’s statement, that “the stridulation produced by some of the Locustidæ is so loud that it can be heard during the night at the distance of a mile;” and such cases as “the drumming of the snipe’s tail, the tapping of the woodpecker’s beak, the harsh, trumpetlike cry of certain water-fowl,” though Darwin tries to dispose of them on the ground of a difference in æsthetic taste, nevertheless incline one to the belief that the music of the forest troubadours is not so much intended to gratify the æsthetic taste of the female as to guide her to the spot where the male awaits her; for, contrary to common opinion, it is the female in these cases that searches for a male and not vice versâ. Montagu, for instance, asserts that “males of song-birds and of many others do not in general search for the female, but, on the contrary, their business in spring is to perch on some conspicuous spot, breathing out their full and amorous notes, which, by instinct, the female knows, and repairs to the spot to choose her mate.” And Dr. Hartman, speaking of the American Cicada septemdecim, says: “The drums are now heard in all directions. This I believe to be the marital summons from the males. Standing in thick chestnut sprouts about as high as my head, where hundreds were around me, I observed the females coming around the drumming males.” And, says Darwin, “the spel of the blackcock certainly serves as a call to the female, for it has been known to bring four or five females from a distance to a male under confinement; but as the blackcock continues his spel for hours during successive days, and in the case of the capercailzie ‘with an agony of passion,’ we are led to suppose that the females which are present are thus charmed.”
There appears to be no direct evidence, however, that female birds are more charmed by one male than another, and prefer him on account of his superior song, as the theory of Sexual Selection postulates. And when we remember that likewise there is no evidence that birds, etc., are ever influenced in their choice by the superior colours of certain males, and that in fact it is the rule for the female to follow passively the most vigorous and victorious male, we are brought back to the conclusion with which we set out—that it is not the superior songster who wins the female by charming her, but the loudest and most persistent songster, by guiding her to the courting-place.
Darwin himself evidently felt the weakness of his position, for he constantly speaks of “love-charms or love-calls” in the same sentence. Thus, “the true song of most birds and various strange cries are uttered chiefly during the breeding-season, and serve as a charm, or merely as a call-note, to the other sex.” Again: “It is often difficult to conjecture whether the many strange cries and notes uttered by male birds during the breeding-season serve as a charm or merely as a call to the female.” The distinction between love “charms” and mere “calls” is of course of the utmost importance. For if male song charms the females and influences them in their choice, we have Sexual-æsthetic-female Selection. But if the male song merely serves as a call to the female and as a sign of species-recognition, then Natural Selection accounts for everything, because the most vigorous, loudest, and most persistent male will have the choice of the most numerous females brought to his side by his musical efforts.
LOVE-DANCES AND DISPLAY
There is one more important link in the chain of Darwin’s reasoning, which must be broken before his theory of Sexual Selection can be regarded as demolished. The mad antics of the blackcock and other birds have been already referred to; and some of the lower animals seem to endeavour to surpass them, as, for example, the male alligator, who strives to attract the attention of the female by splashing and roaring in the water; “swollen to an extent ready to burst, with its head and tail lifted up, he spins or twirls round on the surface of the water, like an Indian chief rehearsing his feats of war.” “To suppose,” says Darwin, “that the females do not appreciate the beauty of the males, is to admit that their splendid decorations, all their pomp and display, are useless; and this is incredible.”
But are there no other ways of accounting for all this “pomp and display”? Certainly, several of them. We have seen that the most vigorous males are those which are most highly ornamented, and that it is the vigour and vivacity of the males that seems to decide the choice of the females where there is any. Now instinct, i.e. inherited experience, teaches the female the connection between vigour and display of ornament, and influences her choice accordingly. Again, the males indulge in their display for the purpose of arousing the attention of the passive female. This supposition is rendered the more probable by Darwin’s admission that “we must be cautious in concluding that the wings are spread out solely for display, as some birds do so whose wings are not beautiful.”
A third motive of display is the need of finding an outlet for overflowing nervous energy and excitement. To this Mr. Wallace refers as follows: “At pairing time the male is in a state of excitement and full of exuberant energy. Even unornamented birds flutter their wings or spread them out, erect their tails or crests, and thus give vent to the nervous excitability with which they are overcharged.” “It is not improbable,” he continues—and this suggests a fourth use of display—"that crests and other erectile feathers may be primarily of use in frightening away enemies, since they are generally erected when angry or during combat."
A fifth motive of display is suggested by an analogy furnished by human butterflies and birds of Paradise. Among animals where the sexes differ, it is commonly the male who is adorned the most. With us it is the women. But woman’s fineries are not intended to charm the eyes of men, but to excite one another’s rivalry and envy. Now it seems that male birds, with whose plumes our heartless women are so fond of decking themselves, are guilty of an analogous weakness. They will sometimes display their ornaments, says Darwin, “when not in the presence of the females, as occasionally occurs with grouse at their holyholy places, and as may be noticed with the peacock; this latter bird, however, evidently wishes
