The hen, when she has laid an egg, repeats the same note very often,
and concludes with the sixth above, which she holds for a longer time
(26. The Hon. Daines Barrington, Philosophical Transactions, 1773, p.
252.); and thus she expresses her joy. Some social birds apparently
call to each other for aid; and as they flit from tree to tree, the
flock is kept together by chirp answering chirp. During the nocturnal
migrations of geese and other water-fowl, sonorous clangs from the van
may be heard in the darkness overhead, answered by clangs in the rear.
Certain cries serve as danger signals, which, as the sportsman knows to
his cost, are understood by the same species and by others. The
domestic cock crows, and the humming-bird chirps, in triumph over a
defeated rival. The true song, however, of most birds and various
strange cries are chiefly uttered during the breeding-season, and serve
as a charm, or merely as a call-note, to the other sex.
Naturalists are much divided with respect to the object of the singing
of birds. Few more careful observers ever lived than Montagu, and he
maintained that the males of song-birds and of many others do not in
general search for the female, but, on the contrary, their business in
the 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. (27. Ornithological
Dictionary, 1833, p. 475.) Mr. Jenner Weir informs me that this is
certainly the case with the nightingale. Bechstein, who kept birds
during his whole life, asserts, that the female canary always chooses
the best singer, and that in a state of nature the female finch selects
that male out of a hundred whose notes please her most. (28.
Naturgeschichte der Stubenvogel, 1840, s. 4. Mr. Harrison Weir
likewise writes to me: I am informed that the best singing males
generally get a mate first, when they are bred in the same room. )
There can be no doubt that birds closely attend to each other s song.
Mr. Weir has told me of the case of a bullfinch which had been taught
to pipe a German waltz, and who was so good a performer that he cost
ten guineas; when this bird was first introduced into a room where
other birds were kept and he began to sing, all the others, consisting
of about twenty linnets and canaries, ranged themselves on the nearest
side of their cages, and listened with the greatest interest to the new
performer. Many naturalists believe that the singing of birds is almost
exclusively the effect of rivalry and emulation, and not for the sake
of charming their mates. This was the opinion of Daines Barrington and
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