Immerse in Classic Audiobooks, then Master English
Thousands of timeless Project Gutenberg masterpieces — 100% free and completely ad-free! Experience LibriVox audio with word-by-word synchronized text, bilingual lookup, and an SRS vocabulary trainer.
Wallace opposed Darwin's theory of sexual selection, but it can scarcely be said that his attitude toward it bears critical examination.
On the one hand, as has already been noted, he saw but one side of that theory and that the unessential side, and, on the other hand, his own view really coincided with the more essential elements in Darwin's theory.
In his _Tropical Nature_ he admitted that the male's "persistency and energy win the day," and also that this "vigor and liveliness" of the male are usually associated with intense coloration, while twenty years later (in his _Darwinism_) he admitted also that it is highly probable that the female is pleased or excited by the male's display.
But all that is really essential in Darwin's theory is involved, directly or indirectly, in these admissions.
Espinas, in 1878, in his suggestive book, _Des Sociétés Animales_, described the odors, colors and forms, sounds, games, parades, and mock battles of animals, approaching the subject in a somewhat more psychological spirit than either Darwin or Wallace, and he somewhat more clearly apprehended the object of these phenomena in producing mutual excitement and stimulating tumescence.
He noted the significance of the action of the hermaphroditic snails in inserting their darts into each other's flesh near the vulva in order to cause preliminary excitation.
He remarks of this whole group of phenomena: "It is the preliminary of sexual union, it constitutes the first act of it.
By it the image of the male is graven on the consciousness of the female, and in a manner impregnates it, so as to determine there, as the effects of this representation descend to the depths of the organism, the physiological modifications necessary to fecundation."
Beaunis, again, in an analysis of the sexual sensations, was inclined to think that the dances and parades of the male are solely intended to excite the female, not perceiving, however, that they at the same time serve to further excite the male also.
[24] A better and more comprehensive statement was reached by Tillier, who, to some extent, may be said to have anticipated Groos.
Darwin, Tillier pointed out, had not sufficiently taken into account the coexistence of combat and courtship, nor the order of the phenomena.
Courtship without combat, Tillier argued, is rare; "there is a normal coexistence of combat and courtship."
[25] Moreover, he proceeded, force is the chief factor in determining the possession of the female by the male, who in some species is even prepared to exert force on her; so that the female has little opportunity of sexual selection, though she is always present at these combats.
He then emphasized the significant fact that courtship takes place long after pairing has ceased, and the question of selection thus been eliminated.
The object of courtship, he concluded, is not sexual selection by the female, but the sexual excitement of both male and female, such excitement, he asserted, not only rendering coupling easier, but favoring fecundation.
Modesty, also, Tillier further argued, again anticipating Groos, works toward the same end; it renders the male more ardent, and by retarding coupling may also increase the secretions of the sexual glands and favor the chances of reproduction.
[26] In a charming volume entitled _The Naturalist in La Plata_ (1892) Mr. W.
H.
Hudson included a remarkable chapter on "Music and Dancing in Nature."
In this chapter he described many of the dances, songs, and love-antics of birds, but regarded all such phenomena as merely "periodical fits of gladness."
While, however, we may quite well agree with Mr. Hudson that conscious sexual gratification on the part of the female is not the cause of music and dancing performances in birds, nor of the brighter colors and ornaments that distinguish the male, such an opinion by no means excludes the conclusion that these phenomena are primarily sexual and intimately connected with the process of tumescence in both sexes.
It is noteworthy that, according to H.
E.
Howard ("On Sexual Selection in Birds," _Zoölogist_, Nov.
, 1903), color is most developed just before pairing, rapidly becoming less beautiful--even within a few hours--after this, and the most beautiful male is most successful in getting paired.
The fact that, as Mr. Hudson himself points out, it is at the season of love that these manifestations mainly, if not exclusively, appear, and that it is the more brilliant and highly endowed males which play the chief part in them, only serves to confirm such a conclusion.
To argue, with Mr. Hudson, that they cannot be sexual because they sometimes occur before the arrival of the females, is much the same as to argue that the antics of a kitten with a feather or a reel have no relationship whatever to mice.
The birds that began earliest to practise their accomplishments would probably have most chance of success when the females arrived.
Darwin himself said that nothing is commoner than for animals to take pleasure in practising whatever instinct they follow at other times for some real good.
These manifestations are primarily for the sake of producing sexual tumescence, and could not well have been developed to the height they have reached unless they were connected closely with propagation.
That they may incidentally serve to express "gladness" one need not feel called upon to question.
Another observer of birds, Mr. E.
Selous, has made observations which are of interest in this connection.
He finds that all bird-dances are not nuptial, but that some birds--the stone-curlew (or great plover), for example--have different kinds of dances.
Among these birds he has made the observation, very significant from our present point of view, that the nuptial dances, taken part in by both of the pair, are immediately followed by intercourse.
In spring "all such runnings and chasings are, at this time, but a part of the business of pairing, and one divines at once that such attitudes are of a sexual character....
Here we have a bird with distinct nuptial (sexual) and social (non-sexual) forms of display or antics, and the former as well as the latter are equally indulged in by both sexes."
(E.
Selous, _Bird Watching_, pp. 15-20. ) The same author (ibid.
, pp. 79, 94) argues that in the fights of two males for one female--with violent emotion on one side and interested curiosity on the other--the attitude of the former "might gradually come to be a display made entirely for the female, and of the latter a greater or less degree of pleasurable excitement raised by it, with a choice in accordance."
On this view the interest of the female would first have been directed, not to the plumage, but to the frenzied actions and antics of the male.
From these antics in undecorated birds would gradually develop the interest in waving plumes and fluttering wings.
Such a dance might come to be of a quite formal and non-courting nature.
Last, we owe to Professor Häcker what may fairly be regarded, in all main outlines, as an almost final statement of the matter.
In his _Gesang der Vögel_ (1900) he gives a very clear account of the evolution of bird-song, which he regards as the most essential element in all this group of manifestations, furnishing the key also to the dancing and other antics.
Originally the song consists only of call-cries and recognition-notes.
Under the parallel influence of natural selection and sexual selection they become at the pairing season reflexes of excitement and thus develop into methods of producing excitement, in the male by the muscular energy required, and in the female through the ear;
finally they become play, though here also it is probable that use is not excluded.
Thus, so far as the male bird is concerned, bird-song possesses a primary prenuptial significance in attracting the female, a secondary nuptial significance in producing excitement (p. 48).
He holds also that the less-developed voices of the females aid in attaining the same end (p. 51).
Finally, bird-song possesses a tertiary extranuptial significance (including exercise play, expression of gladness).
Häcker points out, at the same time, that the maintenance of some degree of sexual excitement beyond pairing time may be of value for the preservation of the species, in case of disturbance during breeding and consequent necessity for commencing breeding over again.
Such a theory as this fairly coincides with the views brought forward in the preceding pages,--views which are believed to be in harmony with the general trend of thought today,--since it emphasizes the importance of tumescence and all that favors tumescence in the sexual process.
The so-called esthetic element in sexual selection is only indirectly of importance.
The male's beauty is really a symbol of his force.
It will be seen that this attitude toward the facts of tumescence among birds and other animals includes the recognition of dances, songs, etc. , as expressions of "gladness."
As such they are closely comparable to the art manifestations among human races.
Here, as Weismann in his _Gedanken über Musik_ has remarked, we may regard the artistic faculty as a by-product: "This [musical] faculty is, as it were, the mental hand with which we play on our own emotional nature, a hand not shaped for this purpose, not due to the necessity for the enjoyment of music, but owing its origin to entirely different requirements."
The psychological significance of these facts has been carefully studied and admirably developed by Groos in his classic works on the play instinct in animals and in men.
[27] Going beyond Wallace, Groos denies _conscious_ sexual selection, but, as he points out, this by no means involves the denial of unconscious selection in the sense that "the female is most easily won by the male who most strongly excites her sexual instincts."
Groos further quotes a pregnant generalization of Ziegler: "In all animals a high degree of excitement of the nervous system is _necessary to procreation_, and thus we find an excited prelude to procreation widely spread."
[28] Such a stage, indeed, as Groos points out, is usually necessary before any markedly passionate discharge of motor energy, as may be observed in angry dogs and the Homeric heroes.
While, however, in other motor explosions the prelude may be reduced to a minimum, in courtship it is found in a highly marked degree.
The primary object of courtship, Groos insists, is to produce sexual excitement.
It is true that Groos's main propositions were by no means novel.
Thus, as I have pointed out, he was at most points anticipated by Tillier.
But Groos developed the argument in so masterly a manner, and with so many wide-ranging illustrations, that he has carried conviction where the mere insight of others had passed unperceived.
Since Darwin wrote the _Descent of Man_ the chief step in the development of the theory of sexual selection has been taken by Groos, who has at the same time made it clear that sexual selection is largely a special case of natural selection.
[29] The conjunction of the sexes is seen to be an end only to be obtained with much struggle; the difficulty of achieving sexual erethism in both sexes, the difficulty of so stimulating such erethism in the female that her instinctive coyness is overcome, these difficulties the best and most vigorous males,[30] those most adapted in other respects to carry on the race, may most easily overcome.
In this connection we may note what Marro has said in another connection, when attempting to answer the question why it is that among savages courtship becomes so often a matter in which persuasion takes the form of force.
The explanation, he remarks, is yet very simple.
Force is the foundation of virility, and its psychic manifestation is courage.
In the struggle for life violence is the first virtue.
The modesty of women--in its primordial form consisting in physical resistance, active or passive, to the assaults of the male--aided selection by putting to the test man's most important quality, force.
Thus it is that when choosing among rivals for her favors a woman attributes value to violence.
[31] Marro thus independently confirms the result reached by Groos.
The debate which has for so many years been proceeding concerning the validity of the theory of sexual selection may now be said to be brought to an end.
Those who supported Darwin and those who opposed him were, both alike, in part right and in part wrong, and it is now possible to combine the elements of truth on either side into a coherent whole.
This is now beginning to be widely recognized; Lloyd Morgan,[32] for instance, has readjusted his position as regards the "pairing instinct" in the light of Groos's contribution to the subject.
"The hypothesis of sexual selection," he concludes, "suggests that the accepted male is the one which adequately evokes the pairing impulse....
Courtship may thus be regarded from the physiological point of view as a means of producing the requisite amount of pairing hunger; of stimulating the whole system and facilitating general and special vascular changes; of creating that state of profound and explosive irritability which has for its psychological concomitant or antecedent an imperious and irresistible craving....
Courtship is thus the strong and steady bending of the bow that the arrow may find its mark in a biological end of the highest importance in the survival of a healthy and vigorous race."
Having thus viewed the matter broadly, we may consider in detail a few examples of the process of tumescence among the lower animals and man, for, as will be seen, the process in both is identical.
As regards animal courtship, the best treasury of facts is Brehm's _Thierleben_, while Büchner's _Liebe und Liebes-Leben in der Thierwelt_ is a useful summary; the admirable discussion of bird-dancing and other forms of courtship in Häcker's _Gesang der Vögel_, chapter iv, may also be consulted.
As regards man, Wallaschek's _Primitive Music_, chapter vii, brings together much scattered material, and is all the more valuable since the author rejects any form of sexual selection;
Hirn's _Origins of Art_, chapter xvii, is well worth reading, and Finck's _Primitive Love and Love-stories_ contains a large amount of miscellaneous information.
I have preferred not to draw on any of these easily accessible sources (except that in one or two cases I have utilized references they supplied), but here simply furnish illustrations met with in the course of my own reading.
Even in the hermaphroditic slugs (_Limax maximus_) the process of courtship is slow and elaborate.
It has been described by James Bladon ("The Loves of the Slug [_Limax cinereus_]," _Zoölogist_, vol. xv, 1857, p. 6272).
It begins toward midnight on sultry summer nights, one slug slowly following another, resting its mouth on what may be called the tail of the first, and following its every movement.
Finally they stop and begin crawling around each other, emitting large quantities of mucus.
When this has constituted a mass of sufficient size and consistence they suspend themselves from it by a cord of mucus from nine to fifteen inches in length, continuing to turn round each other till their bodies form a cone.
Then the organs of generation are protruded from their orifice near the mouth and, hanging down a short distance, touch each other.
They also then begin again the same spiral motion, twisting around each other, like a two-strand cord, assuming various and beautiful forms, sometimes like an inverted agaric, or a foliated murex, or a leaf of curled parsley, the light falling on the ever-varying surface of the generative organs sometimes producing iridescence.
It is not until after a considerable time that the organs untwist and are withdrawn and the bodies separate, to crawl up the suspending cord and depart.
Some snails have a special organ for creating sexual excitement.
A remarkable part of the reproductive system in many of the true Helicidæ is the so-called _dart, Liebespfeil_, or _telum Veneris_.
It consists of a straight or curved, sometimes slightly twisted, tubular shaft of carbonate of lime, tapering to a fine point above, and enlarging gradually, more often somewhat abruptly, to the base.
The sides of the shaft are sometimes furnished with two or more blades; these are apparently not for cutting purposes, but simply to brace the stem.
The dart is contained in a dart-sac, which is attached as a sort of pocket to the vagina, at no great distance from its orifice.
In _Helix aspersa_ the dart is about five-sixteenths of an inch in length, and one-eighth of an inch in breadth at its base.
It appears most probable that the dart is employed as an adjunct for the sexual act.
Besides the fact of the position of the dart-sac anatomically, we find that the darts are extended and become imbedded in the flesh, just before or during the act of copulation.
It may be regarded, then, as an organ whose functions induce excitement preparatory to sexual union.
It only occurs in well-grown specimens.
(Rev. L. H.
Cooke, "Molluscs," _Cambridge Natural History_, vol. iii, p. 143. ) Racovitza has shown that in the octopus (_Octopus vulgaris_) courtship is carried on with considerable delicacy, and not brutally, as had previously been supposed.
The male gently stretches out his third arm on the right and caresses the female with its extremity, eventually passing it into the chamber formed by the mantle.
The female contracts spasmodically, but does not attempt to move.
They remain thus about an hour or more, and during this time the male shifts the arm from one oviduct to the other.
Finally he withdraws his arm, caresses her with it for a few moments, and then replaces it with his other arm.
(E.
G.
Racovitza, in _Archives de Zoölogie Expérimentale_, quoted in _Natural Science_, November, 1894. ) The phenomena of courtship are very well illustrated by spiders.
Peckham, who has carefully studied them, tells us of _Saitis pulex_: "On May 24th we found a mature female, and placed her in one of the larger boxes, and the next day we put a male in with her.
He saw her as she stood perfectly still, twelve inches away;
the glance seemed to excite him, and he at once moved toward her;
when some four inches from her he stood still, and then began the most remarkable performances that an amorous male could offer to an admiring female.
She eyed him eagerly, changing her position from time to time so that he might be always in view.
He, raising his whole body on one side by straightening out the legs, and lowering it on the other by folding the first two pairs of legs up and under, leaned so far over as to be in danger of losing his balance, which he only maintained by sliding rapidly toward the lowered side.
The palpus, too, on this side was turned back to correspond to the direction of the legs nearest it.
He moved in a semicircle for about two inches, and then instantly reversed the position of the legs and circled in the opposite direction, gradually approaching nearer and nearer to the female.
Now she dashes toward him, while he, raising his first pair of legs, extends them upward and forward as if to hold her off, but withal slowly retreats.
Again and again he circles from side to side, she gazing toward him in a softer mood, evidently admiring the grace of his antics.
This is repeated until we have counted one hundred and eleven circles made by the ardent little male.
Now he approaches nearer and nearer, and when almost within reach whirls madly around and around her, she joining and whirling with him in a giddy maze.
Again he falls back and resumes his semicircular motions, with his body tilted over; she, all excitement, lowers her head and raises her body so that it is almost vertical; both draw nearer; she moves slowly under him, he crawling over her head, and the mating is accomplished."
The same author thus describes the courtship of _Dendryphantes elegans_: "While from three to five inches distant from her, he begins to wave his plumy first legs in a way that reminds one of a windmill.
She eyes him fiercely, and he keeps at a proper distance for a long time.
If he comes close she dashes at him, and he quickly retreats.
Sometimes he becomes bolder, and when within an inch, pauses, with the first legs outstretched before him, not raised as is common in other species; the palpi also are held stiffly out in front with the points together.
Again she drives him off, and so the play continues.
Now the male grows excited as he approaches her, and while still several inches away, whirls completely around and around; pausing, he runs closer and begins to make his abdomen quiver as he stands on tiptoe in front of her.
Prancing from side to side, he grows bolder and bolder, while she seems less fierce, and yielding to the excitement, lifts up her magnificently iridescent abdomen, holding it at one time vertical, and at another sideways to him.
She no longer rushes at him, but retreats a little as he approaches.
At last he comes close to her, lying flat, with his first legs stretched out and quivering.
With the tips of his front legs he gently pats her; this seems to arouse the old demon of resistance, and she drives him back.
Again and again he pats her with a caressing movement, gradually creeping nearer and nearer, which she now permits without resistance, until he crawls over her head to her abdomen, far enough to reach the epigynum with his palpus."
(G.
W.
Peckham, "Sexual Selection of Spiders," _Occasional Papers of the Natural History Society of Wisconsin_, 1889, quoted in _Nature_, August 21, 1890. ) The courtship of another spider, the _Agelena labyrinthica_, has been studied by Lécaillon ("Les Instincts et les Psychismes des Araignées," _Revue Scientifique_, Sept.
15, 1906. ) The male enters the female's web and may be found there about the middle of July.
When courtship has begun it is not interrupted by the closest observation, even under the magnifying glass.
At first it is the male which seeks to couple and he pursues the female over her web till she consents.
The pursuit may last some hours, the male agitating his abdomen in a peculiar way, while the female simply retreats a short distance without allowing herself to be approached.
At last the female holds herself completely motionless, and then the male approaches, seizes her, places her on her side, sometimes carrying her to a more suitable part of the web.
Then one of his copulative apparatus is applied to the female genital opening, and copulation begins.
When completed (on an average in about two hours) the male withdraws his copulatory palpus and turns over the female, who is still inert, on to her other side, then brings his second copulatory apparatus to the female opening and starts afresh.
When the process is definitely completed the male leaves the female, suddenly retiring to a little distance.
The female, who had remained completely motionless for four hours, suddenly runs after the male.
But she only pursues him for a short distance, and the two spiders remain together without any danger to either.
Lécaillon disbelieves the statement of Romanes (in his _Animal Intelligence_) that the female eats the male after copulation.
But this certainly seems to occur sometimes among insects, as illustrated by the following instance described by so careful an observer of insects as Fabre.
The _Mantis religiosa_ is described by Fabre as contemplating the female for a long time in an attitude of ecstasy.
She remains still and seems indifferent.
He is small and she is large.
At last he approaches; spreads his wings, which tremble convulsively; leaps on her back, and fixes himself there.
The preludes are long and the coupling itself sometimes occupies five or six hours.
Then they separate.
But the same day or the following day she seizes him and eats him up in small mouthfuls.
She will permit a whole series of males to have intercourse with her, always eating them up directly afterward.
Fabre has even seen her eating the male while still on her back, his head and neck gone, but his body still firmly attached.
(J.
H.
Fabre, _Souvenirs Entomologiques_, fifth series, p. 307. ) Fabre also describes in great detail (ibid.
, ninth series, chs.
xxi-xxii) the sexual parades of the Languedoc scorpion (_Scorpio occitanus_), an arachnid.
These parades are in public; for their subsequent intercourse the couple seek complete seclusion, and the female finally eats the male.
An insect (a species of _Empis_) has been described which excites the female by manipulating a large balloon.
"This is of elliptical shape, about seven millimeters long (nearly twice as long as the fly), hollow, and composed entirely of a single layer of minute bubbles, nearly uniform in size, arranged in regular circles concentric with the axis of the structure.
The beautiful, glistening whiteness of the object when the sun shines upon it makes it very conspicuous.
The bubbles were slightly viscid, and in nearly every case there was a small fly pressed into the front end of the balloon, apparently as food for the _Empis_.
In all cases they were dead.
The balloon appears to be made while the insect is flying in the air.
Those flying highest had the smallest balloons.
The bubbles are probably produced by some modification of the anal organs.
It is possible that the captured fly serves as a nucleus to begin the balloon on.
One case of a captured fly but no balloon was observed.
After commencing, it is probable that the rest of the structure is made by revolving the completed part between the hind legs and adding more bubbles somewhat spirally.
The posterior end of the balloon is left more or less open.
The purpose of this structure is to attract the female.
When numerous males were flying up and down the road, it happened several times that a female was seen to approach them from some choke-cherry blossoms near by.
The males immediately gathered in her path, and she with little hesitation selected for a mate the one with the largest balloon, taking a position _upon his back_.
After copulation had begun, the pair would settle down toward the ground, select a quiet spot, and the female would alight by placing her front legs across a horizontal grass blade, her head resting against the blade so as to brace the body in position.
Here she would continue to hold the male beneath her for a little time, until the process was finished.
The male, meanwhile, would be rolling the balloon about in a variety of positions, juggling with it, one might almost say.
After the male and female parted company, the male immediately dropped the balloon upon the ground, and it was greedily seized by ants.
No illustration could properly show the beauty of the balloon."
(Aldrich and Turley, "A Balloon-making Fly," _American Naturalist_, October, 1899. ) "In many species of moths the males 'assemble' around the freshly emerged female, but no special advantage appears to attend on early arrival.
The female sits apparently motionless, while the little crowd of suitors buzz around her for several minutes.
Suddenly, and, as far as one can see, without any sign from the female, one of the males pairs with her and all the others immediately disappear.
In these cases the males do not fight or struggle in any way, and as one watches the ceremony the wonder arises as to how the moment is determined, and why the pairing did not take place before.
Proximity does not decide the point, for long beforehand the males often alight close to the female and brush against her with fluttering wings.
I have watched the process exactly as I have described it in a common Northern _Noctua_, the antler moth (_Charæax graminis_), and I have seen the same thing among beetles."
(E.
B.
Poulton, _The Colors of Animals_, 1890, p. 391. ) This author mentions that among some butterflies the females take the active part.
The example here quoted of courtship among moths illustrates how phenomena which are with difficulty explicable by the theory of sexual selection in its original form become at once intelligible when we realize the importance of tumescence in courtship.
Of the Argentine cow-bird (_Molothrus bonariensis_) Hudson says (_Argentine Ornithology_, vol. i, p. 73): "The song of the male, particularly when making love, is accompanied with gestures and actions somewhat like those of the domestic pigeon.
He swells himself out, beating the ground with his wings, and uttering a series of deep internal notes, followed by others loud and clear;
and occasionally, when uttering them, he suddenly takes wing and flies directly away from the female to a distance of fifty yards, and performs a wide circuit about her in the air, singing all the time.
The homely object of his passion always appears utterly indifferent to this curious and pretty performance; yet she must be even more impressionable than most female birds, since she continues scattering about her parasitical and often wasted eggs during four months in every year."
Of a tyrant-bird (_Pitangus Bolivianus_) Hudson writes (_Argentine Ornithology_, vol. i, p. 148): "Though the male and female are greatly attached, they do not go afield to hunt in company, but separate to meet again at intervals during the day.
One of a couple (say, the female) returns to the trees where they are accustomed to meet, and after a time, becoming impatient or anxious at the delay of her consort, utters a very long, clear call-note.
He is perhaps a quarter of a mile away, watching for a frog beside a pool, or beating over a thistle-bed, but he hears the note and presently responds with one of equal power.
Then, perhaps, for half an hour, at intervals of half a minute, the birds answer each other, though the powerful call of the one must interfere with his hunting.
At length he returns; then the two birds, perched close together, with their yellow bosoms almost touching, crests elevated, and beating the branch with their wings, scream their loudest notes in concert--a confused jubilant noise that rings through the whole plantation.
Their joy at meeting is patent, and their action corresponds to the warm embrace of a loving human couple."
Of the red-breasted marsh-bird (_Leistes superciliaris_) Hudson (_Argentine Ornithology_, vol. i, p. 100) writes: "These birds are migratory, and appear everywhere in the eastern part of the Argentine country early in October, arriving singly, after which each male takes up a position in a field or open space abounding with coarse grass and herbage, where he spends most of his time perched on the summit of a tall stalk or weed, his glowing crimson bosom showing at a distance like some splendid flower above the herbage.
At intervals of two or three minutes he soars vertically up to a height of twenty or twenty-five yards to utter his song, composed of a single long, powerful and rather musical note, ending with an attempt at a flourish, during which the bird flutters and turns about in the air; then, as if discouraged at his failure, he drops down, emitting harsh, guttural chirps, to resume his stand.
Meanwhile the female is invisible, keeping closely concealed under the long grass.
But at length, attracted perhaps by the bright bosom and aërial music of the male, she occasionally exhibits herself for a few moments, starting up with a wild zigzag flight, and, darting this way and that, presently drops into the grass once more.
The moment she appears above the grass the male gives chase, and they vanish from sight together."
"Courtship with the mallard," says J. G.
Millais (_Natural History of British Ducks_, p. 6), "appears to be carried on by both sexes, though generally three or four drakes are seen showing themselves off to attract the attention of a single duck.
Swimming round her, in a coy and semi-self-conscious manner, they now and again all stop quite still, nod, bow, and throw their necks out in token of their admiration and their desire of a favorable response.
But the most interesting display is when all the drakes simultaneously stand up in the water and rapidly pass their bills down their breasts, uttering at the same time a low single note somewhat like the first half of the call that teal and pintail make when 'showing off.'
At other times the love-making of the drake seems to be rather passive than active.
While graciously allowing himself to be courted, he holds his head high with conscious pride, and accepts as a matter of course any attention that may be paid to him.
A proud bird is he when three or four ducks come swimming along beside and around him, uttering a curious guttural note, and at the same time dipping their bills in quick succession to right and left.
He knows what that means, and carries himself with even greater dignity than before.
In the end, however, he must give in.
As a last appeal, one of his lady lovers may coyly lower herself in the water till only the top of her back, head, and neck is seen, and so fascinating an advance as this no drake of any sensibility can withstand."
The courting of the Argus pheasant, noted for the extreme beauty of the male's plumage, was observed by H. O.
Forbes in Sumatra.
It is the habit of this bird to make "a large circus, some ten or twelve feet in diameter, in the forest, which it clears of every leaf and twig and branch, till the ground is perfectly swept and garnished.
On the margin of this circus there is invariably a projecting branch or high-arched root, at a few feet elevation above the ground, on which the female bird takes its place, while in the ring the male--the male birds alone possess great decoration--shows off all its magnificence for the gratification and pleasure of his consort and to exalt himself in her eyes."
(H.
O.
Forbes, _A.
Naturalist's Wanderings_, 1885, p. 131. ) "All ostriches, adults as well as chicks, have a strange habit known as 'waltzing.'
After running for a few hundred yards they will also stop, and, with raised wings, spin around rapidly for some time after until quite giddy, when a broken leg occasionally occurs....
Vicious cocks 'roll' when challenging to fight or when wooing the hen.
The cock will suddenly bump down on to his knees (the ankle-joint), open his wings, and then swing them alternately backward and forward, as if on a pivot....
While rolling, every feather over the whole body is on end, and the plumes are open, like a large white fan.
At such a time the bird sees very imperfectly, if at all; in fact, he seems so preoccupied that, if pursued, one may often approach unnoticed.
Just before rolling, a cock, especially if courting the hen, will often run slowly and daintily on the points of his toes, with neck slightly inflated, upright, and rigid, the tail half-drooped, and all his body-feathers fluffed up; the wings raised and expanded, the inside edges touching the sides of the neck for nearly the whole of its length, and the plumes showing separately, like an open fan.
In no other attitude is the splendid beauty of his plumage displayed to such advantage."
(S.
C.
Cronwright Schreiner, "The Ostrich," _Zoölogist_, March, 1897. )
們使瀏覽 (Local Storage) 來住您主題好、體大小、以後播目進度字本
We use browser Local Storage to remember your theme preferences, font sizes, and last played track progress, as well as vocabulary lists.
請用QR Code,即無縫接軌目入聽進度
自動分析當前章節英文文本,依據考試與難度標籤篩選重點生字,可一鍵批次匯入生字本。
請確認或修改檔案儲存名稱: