162
WILLIAM N. TAVOLGA
charges (Vincent, 1963b). Despite efforts to electrically isolate the hydrophone, the acoustic nature of these signals is still doubtful. If true,
this report could become the only definite record of an elasmobranch
producing sounds other than hydrodynamic ones.
111. SOUND DETECTION
A. Historical Background
Since fish have been known, from early times, to be capable of sound
production, it was logically assumed that they could also hear. The earliest
study of significance in this field was the classic report by Weber (1820)
in which he not only described the morphology of the fish ear but also
postulated the function of the small ossicles that in the Ostariophysi connect the swim bladder with the inner ear. He compared these structures,
since known as the Weberian ossicles, to the middle ear bones of mammals and concluded that they functioned in a similar fashion, i.e., to conduct sound from the swim bladder to the fluids of the inner ear.
It was not until after the turn of the century that the ability of fish
to hear was finally established. Several experimenters, notably Kreidl
(1895), had concluded that fish were deaf or, at best, could receive some
vibrations through a cutaneous sense. However, the investigations of
Bigelow (1904), Parker (1902, 1910a,b, 1918), and Parker and van
Heusen (1917) proved conclusively that fish receive sound stimuli both
through the inner ear and the lateral line. Numerous reports confirming
Parker’s conclusions followed, in which many other species of fish were
shown to possess the ability to detect water-borne sound. The significant
studies and reviews of the time included those by Bull ( 1928,1929, 1930),
Evans ( 1935), von Frisch ( 1923, 1936, 1938a), Froloff (1925), LafiteDupont ( 1907), McDonald ( 1922), Marage ( 1906), Moorhouse ( 1933),
and Warner (1932).
The first attempts at any quantitative study of fish hearing consisted
of determinations of the highest frequency to which fish would respond.
In a summary of the results of most of these studies, it is clear that the
upper frequency limits of members of the Ostariophysi are significantly
higher than representatives of other orders (cf. Tables in Lowenstein,
1957, and Moulton, 1963).
In most of the listed reports, little or no data were given on the intensities of the signals used, and, indeed, in many cases the sound stimuli
were poorly controlled, e.g., whistles, plucked strings, and other crude
sound makers. Stetter (1929) was the first to control stimulus intensity
and attempt to measure it.
WILLIAM N. TAVOLGA
charges (Vincent, 1963b). Despite efforts to electrically isolate the hydrophone, the acoustic nature of these signals is still doubtful. If true,
this report could become the only definite record of an elasmobranch
producing sounds other than hydrodynamic ones.
111. SOUND DETECTION
A. Historical Background
Since fish have been known, from early times, to be capable of sound
production, it was logically assumed that they could also hear. The earliest
study of significance in this field was the classic report by Weber (1820)
in which he not only described the morphology of the fish ear but also
postulated the function of the small ossicles that in the Ostariophysi connect the swim bladder with the inner ear. He compared these structures,
since known as the Weberian ossicles, to the middle ear bones of mammals and concluded that they functioned in a similar fashion, i.e., to conduct sound from the swim bladder to the fluids of the inner ear.
It was not until after the turn of the century that the ability of fish
to hear was finally established. Several experimenters, notably Kreidl
(1895), had concluded that fish were deaf or, at best, could receive some
vibrations through a cutaneous sense. However, the investigations of
Bigelow (1904), Parker (1902, 1910a,b, 1918), and Parker and van
Heusen (1917) proved conclusively that fish receive sound stimuli both
through the inner ear and the lateral line. Numerous reports confirming
Parker’s conclusions followed, in which many other species of fish were
shown to possess the ability to detect water-borne sound. The significant
studies and reviews of the time included those by Bull ( 1928,1929, 1930),
Evans ( 1935), von Frisch ( 1923, 1936, 1938a), Froloff (1925), LafiteDupont ( 1907), McDonald ( 1922), Marage ( 1906), Moorhouse ( 1933),
and Warner (1932).
The first attempts at any quantitative study of fish hearing consisted
of determinations of the highest frequency to which fish would respond.
In a summary of the results of most of these studies, it is clear that the
upper frequency limits of members of the Ostariophysi are significantly
higher than representatives of other orders (cf. Tables in Lowenstein,
1957, and Moulton, 1963).
In most of the listed reports, little or no data were given on the intensities of the signals used, and, indeed, in many cases the sound stimuli
were poorly controlled, e.g., whistles, plucked strings, and other crude
sound makers. Stetter (1929) was the first to control stimulus intensity
and attempt to measure it.