RESUMO
It has previously been shown that at least one species of fish (the American shad) in the order clupeiforms (herrings, shads, and relatives) is able to detect sounds up to 180 kHz. However, it has not been clear whether other members of this order are also able to detect ultrasound. It is now demonstrated, using auditory brainstem response (ABR), that at least one additional species, the gulf menhaden (Brevoortia patronus), is able to detect ultrasound, while several other species including the bay anchovy (Anchoa mitchilli), scaled sardine (Harengula jaguana), and Spanish sardine (Sardinella aurita) only detect sounds to about 4 kHz. ABR is used to confirm ultrasonic hearing in the American shad. The results suggest that ultrasound detection may be limited to one subfamily of clupeiforms, the Alosinae. It is suggested that ultrasound detection involves the utricle of the inner ear and speculate as to why, despite having similar ear structures, only one group may detect ultrasound.
Assuntos
Peixes/fisiologia , Detecção de Sinal Psicológico/fisiologia , Ultrassom , Animais , Limiar Auditivo/fisiologia , Comportamento Animal/fisiologia , Tronco Encefálico/fisiologia , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Audição/fisiologiaRESUMO
Thresholds for diffuse, broad-band illumination were obtained for the goldfish (Carassius auratus) by avoidance conditioning. The light source was a television cathode-ray tube whose output was controlled over a range of 140 dB by a combination of 'brightness' control, blanking of scan lines, and neutral density filters. The threshold was calculated in terms of irradiance to be 2-9 X 10(-6) muW cm-2 (+/- a standard deviation of 1-4). The determination of absolute, rather than relative, values, and the use of overhead, diffuse illumination provided data that would be ecologically and behaviourally relevant.
Assuntos
Cyprinidae/fisiologia , Carpa Dourada/fisiologia , Luz , Percepção Visual/fisiologia , Animais , Aprendizagem da Esquiva/fisiologia , Análise EspectralRESUMO
The marine catfish (Arius felis) uses directional hearing for the acoustical detection of obstacles, and is primarily dependent on the vector components of near-field acoustics. Directional sound, detected as lateral line action potentials, produces the strongest response on the side toward the stimulus. Responses are maximal in the 50-150 Hz range. The swim bladder is asymmetrical as a sound generator (7 dB front-to-back ratio). As a sound receiver, the swim bladder is even more directional (24 dB front-to-back ratio at 100 Hz). It is concluded that directional response to sound in fishes can involve the interaction of at least two mechanisms, in this case the lateral line and the swim bladder.
