The Descent of Man

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 armorous 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