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Bullseye
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* Sclater, in Proceedings, Zoological Society, 1860, p. 90, and in
Ibis, vol. iv., 1862, p. 175. Also Salvin, in Ibis, 1860, p. 37.
The diversity of the sounds, both vocal and instrumental, made by
the males of many birds during the breeding-season, and the
diversity of the means for producing such sounds, are highly
remarkable. We thus gain a high idea of their importance for sexual
purposes, and are reminded of the conclusion arrived at as to insects.
It is not difficult to imagine the steps by which the notes of a bird,
primarily used as a mere call or for some other purpose, might have
been improved into a melodious love song. In the case of the
modified feathers, by which the drumming, whistling, or roaring noises
are produced, we know that some birds during their courtship
flutter, shake, or rattle their unmodified feathers together; and if
the females were led to select the best performers, the males which
possessed the strongest or thickest, or most attenuated feathers,
situated on any part of the body, would be the most successful; and
thus by slow degrees the feathers might be modified to almost any
extent. The females, of course, would not notice each slight
successive alteration in shape, but only the sounds thus produced.
It is a curious fact that in the same class of animals, sounds so
different as the drumming of the snipe's tail, the tapping of the
woodpecker's beak, the harsh trumpet-like cry of certain water-fowl,
the cooing of the turtle-dove, and the song of the nightingale, should
all be pleasing to the females of the several species. But we must not
judge of the tastes of distinct species by a uniform standard; nor
must we judge by the standard of man's taste. Even with man, we should
remember what discordant noises, the beating of tom-toms and the
shrill notes of reeds, please the ears of savages. Sir S. Baker
remarks,* that "as the stomach of the Arab prefers the raw meat and
reeking liver taken hot from the animal, so does his ear prefer his
equally coarse and discordant music to all other."
* The Nile Tributaries of Abyssinia, 1867, p. 203.
Love Antics and Dances.- The curious love gestures of some birds
have already been incidentally noticed; so that little need here be
added. In Northern America large numbers of a grouse, the Tetrao
phasianellus, meet every morning during the breeding-season on a
selected level spot, and here they run round and round in a circle
of about fifteen or twenty feet in diameter, so that the ground is
worn quite bare, like a fairy-ring. In these partridge-dances, as they
are called by the hunters, the birds assume the strangest attitudes,
and run round, some to the left and some to the right. Audubon
describes the males of a heron (Ardea herodias) as walking about on
their long legs with great dignity before the females, bidding
defiance to their rivals. With one of the disgusting
carrion-vultures (Cathartes jota) the same naturalist states that "the
gesticulations and parade of the males at the beginning of the
love-season are extremely ludicrous." Certain birds perform their
love-antics on the wing, as we have seen with the black African
weaver, instead of on the ground. During the spring our little
white-throat (Sylvia cinerea) often rises a few feet or yards in the
air above some bush, and "flutters with a fitful and fantastic motion,
singing all the while, and then drops to its perch." The great English
bustard throws himself into indescribably odd attitudes whilst
courting the female, as has been figured by Wolf. An allied Indian
bustard (Otis bengalensis) at such times "rises perpendicularly into
the air with a hurried flapping of his wings, raising his crest and
puffing out the feathers of his neck and breast, and then drops to the
ground"; he repeats this manoeuvre several times, at the same time
humming in a peculiar tone. Such females as happen to be near "obey
this saltatory summons," and when they approach he trails his wings
and spreads his tail like a turkey-****.*
* For Tetrao phasianellus, see Richardson, Fauna, Bor. Americana, p.
361, and for further particulars, Capt. Blakiston, Ibis, 1863, p. 125.
For the Cathartes and Ardea, Audubon, Ornithological Biography, vol.
ii., p. 51, and vol. iii., p. 89. On the white-throat, Macgillivray,
History of British Birds, vol. ii., p. 354. On the Indian bustard,
Jerdon, Birds of India, vol. iii., p. 618.
But the most curious case is afforded by three allied genera of
Australian birds, the famous bower-birds,- no doubt the co-descendants
of some ancient species which first acquired the strange instinct of
constructing bowers for performing their love-antics. The bowers
(see fig. 46), which, as we shall hereafter see, are decorated with
feathers, shells, bones, and leaves, are built on the ground for the
sole purpose of courtship, for their nests are formed in trees. Both
sexes assist in the **** of the bowers, but the male is the
principal workman. So strong is this instinct that it is practised
under confinement, and Mr. Strange has described* the habits of some
satin bower-birds which he kept in an aviary in New South Wales. "At
times the male will chase the female all over the aviary, then go to
the bower, pick up a gay feather or a large leaf, utter a curious kind
of note, set all his feathers erect, run round the bower and become so
excited that his eyes appear ready to start from his bead; he
continues opening first one wing then the other, uttering a low,
whistling note, and, like the domestic ****, seems to be picking up
something from the ground, until at last the female goes gently
towards him." Captain Stokes has described the habits and
"play-houses" of another species, the great bower-bird, which was seen
"amusing itself by flying backwards and forwards, taking a shell
alternately from each side, and carrying it through the archway in its
mouth." These curious creations, formed solely as halls of assemblage,
where both sexes amuse themselves and pay their court, must cost the
birds much labor. The bower, for instance, of the fawn-breasted
species, is nearly four feet in length, eighteen inches in height, and
is raised on a thick platform of sticks.
* Gould, Handbook to the Birds of Australia, vol. i., pp. 444,
449, 455. The bower of the satin bower-bird may be seen in the
Zoological Society's Gardens, Regent's Park.
Decoration.- I will first discuss the cases in which the males are
ornamented either exclusively or in a much higher degree than the
females, and in a succeeding chapter those in which both sexes are
equally ornamented, and finally the rare cases in which the female
is somewhat more brightly-coloured than the male. As with the
artificial ornaments used by savage and civilised men, so with the
natural ornaments of birds, the head is the chief seat of decoration.*
The ornaments, as mentioned at the commencement of this chapter, are
wonderfully diversified. The plumes on the front or back of the head
consist of variously-shaped feathers, sometimes capable of **** or
expansion, by which their beautiful colours are fully displayed.
Elegant ear-tufts (see fig. 39, ante) are occasionally present. The
head is sometimes covered with velvety down, as with the pheasant;
or is naked and vividly coloured. The throat, also, is sometimes
ornamented with a beard, wattles, or caruncles. Such appendages are
generally brightly-coloured, and no doubt serve as ornaments, though
not always ornamental in our eyes; for whilst the male is in the act
of courting the female, they often swell and assume vivid tints, as in
the male turkey. At such times the fleshy appendages about the head of
the male tragopan pheasant (Ceriornis temminckii) swell into a large
lappet on the throat and into two horns, one on each side of the
splendid topknot; and these are then coloured of the most intense blue
which I have ever beheld.*(2) The African hornbill (Bucorax
abyssinicus) inflates the scarlet bladder-like wattle on its neck, and
with its wings drooping and tail expanded "makes quite a grand
appearance."*(3) Even the iris of the eye is sometimes more
brightly-coloured in the male than in the female; and this is
frequently the case with the beak, for instance, in our common
blackbird. In Buceros corrugatus, the whole beak and immense casque
are coloured more conspicuously in the male than in the female; and
"the oblique grooves upon the sides of the lower mandible are peculiar
to the male sex."*(4)
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