80
a
b
c
d
Fig. 10 The effect of the gas-fi lled swim bladder horns and chamber on hearing sensitivity in
Chaetodon with different LC morphologies as determined by the auditory evoked potential (AEP)
technique. ( a ) Forcipiger fl avissimus , which lacks an LC and swim bladder horns (see Fig. 5c )
shows little change in normal AEP threshold ( solid circles ) following defl ation of the swim bladder
( open circles ). ( b ) C. ornatissimus has short swim bladder horns with an indirect connection to the
LC (see Fig. 4c ) that we were not able to manipulate. The baseline thresholds extended to 2000 Hz
and appear to increase by approximately 5 dB in the 200–400 Hz band following defl ation of the
swim bladder. ( c ) C. multicinctus has long swim bladder horns with an indirect connection to the
LC (see Fig. 5e ). Baseline thresholds increased in the 200–600 Hz band after gas was evacuated
from the swim bladder horns ( half-fi lled circles ) with a maximum increase of 10 dB at 600 Hz.
T.C. Tricas and J.F. Webb
a
b
c
d
Fig. 10 The effect of the gas-fi lled swim bladder horns and chamber on hearing sensitivity in
Chaetodon with different LC morphologies as determined by the auditory evoked potential (AEP)
technique. ( a ) Forcipiger fl avissimus , which lacks an LC and swim bladder horns (see Fig. 5c )
shows little change in normal AEP threshold ( solid circles ) following defl ation of the swim bladder
( open circles ). ( b ) C. ornatissimus has short swim bladder horns with an indirect connection to the
LC (see Fig. 4c ) that we were not able to manipulate. The baseline thresholds extended to 2000 Hz
and appear to increase by approximately 5 dB in the 200–400 Hz band following defl ation of the
swim bladder. ( c ) C. multicinctus has long swim bladder horns with an indirect connection to the
LC (see Fig. 5e ). Baseline thresholds increased in the 200–600 Hz band after gas was evacuated
from the swim bladder horns ( half-fi lled circles ) with a maximum increase of 10 dB at 600 Hz.
T.C. Tricas and J.F. Webb