Volume 197, Issue 10:
Jun-Xian Shen, Zhi-Min Xu, Albert S. Feng & Peter M. Narins (2011): Large
odorous frogs (Odorrana graminea) produce ultrasonic calls. J. Comp.
Physiol. A 197 (10), 1027-1030.
Abstract: We present the first data on the vocalizations of large odorous
frogs (Odorrana graminea, previously Odorrana livida), from southern China.
The males produce diverse broadband signals most of which contain ultrasonic
harmonics. Six basic call-types were identified based on the number of call
notes, fundamental frequency, call/note duration, frequency modulation
patterns and spectral composition. O. graminea is one of only a few
non-mammalian vertebrates able to detect ultrasound, but its tympanic
membranes are not recessed. These results should stimulate further studies
to provide new insights into the mechanisms underlying high-frequency
communication in anurans.
URL: http://www.springerlink.com/content/6014771488h05526/
For reprints please contact J.-X. Shen (email:
Volume 187, Issue 12:
T. Aran Mooney, Songhai Li, Darlene R. Ketten, Kexiong Wang & Ding Wang
(2011): Auditory temporal resolution and evoked responses to pulsed sounds
for the Yangtze finless porpoises (Neophocaena phocaenoides
asiaeorientalis). J. Comp. Physiol. A 197 (12), 1149-1158.
Abstract: Temporal cues are important for some forms of auditory processing,
such as echolocation. Among odontocetes (toothed whales, dolphins, and
porpoises), it has been suggested that porpoises may have temporal
processing abilities which differ from other odontocetes because of their
relatively narrow auditory filters and longer duration echolocation signals.
This study examined auditory temporal resolution in two Yangtze finless
porpoises (Neophocaena phocaenoides asiaeorientalis) using auditory evoked
potentials (AEPs) to measure: (a) rate following responses and modulation
rate transfer function for 100 kHz centered pulse sounds and (b) hearing
thresholds and response amplitudes generated by individual pulses of
different durations. The animals followed pulses well at modulation rates up
to 1,250 Hz, after which response amplitudes declined until extinguished
beyond 2,500 Hz. The subjects had significantly better hearing thresholds
for longer, narrower-band pulses similar to porpoise echolocation signals
compared to brief, broadband sounds resembling dolphin clicks. Results
indicate that the Yangtze finless porpoise follows individual acoustic
signals at rates similar to other odontocetes tested. Relatively good
sensitivity for longer duration, narrow-band signals suggests that finless
porpoise hearing is well suited to detect their unique echolocation signals.
URL: http://www.springerlink.com/content/f8732855745501t1/
For reprints please contact T. A. Mooney (email:
Julio C. Hechavarría, Ariadna T. Cobo, Yohami Fernández, Silvio Macías,
Manfred Kössl & Emanuel C. Mora (2011): Sound-evoked oscillation and
paradoxical latency shift in the inferior colliculus neurons of the big
fruit-eating bat, Artibeus jamaicensis. J. Comp. Physiol. A 197 (12),
1159-1172.
Abstract: Frequency tuning, temporal response pattern and latency properties
of inferior colliculus neurons were investigated in the big fruit-eating
bat, Artibeus jamaicensis. Neurons having best frequencies between 48?72 kHz
and between 24?32 kHz are overrepresented. The inferior colliculus neurons
had either phasic (consisting in only one response cycle at all stimulus
intensities) or long-lasting oscillatory responses (consisting of multiple
response cycles). Seventeen percent of neurons displayed paradoxical latency
shift, i.e. their response latency increased with increasing sound level.
Three types of paradoxical latency shift were found: (1) stable, that does
not depend on sound duration, (2) duration-dependent, that grows with
increasing sound duration, and (3) progressive, whose magnitude increases
with increasing sound level. The temporal properties of paradoxical latency
shift neurons compare well with those of neurons having long-lasting
oscillatory responses, i.e. median inter-spike intervals and paradoxical
latency shift below 6 ms are overrepresented. In addition, oscillatory and
paradoxical latency shift neurons behave similarly when tested with tones of
different durations. Temporal properties of oscillation and PLS found in the
IC of fruit-eating bats are similar to those found in the IC of
insectivorous bats using downward frequency-modulated echolocation calls.
URL: http://www.springerlink.com/content/l6x1153q40656l5h/
For reprints please contact Julio Hechavarría (email:
Kind regards
Sonja Amoser
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Dr. Sonja Amoser
Steinrieglstraße 286
3400 Weidlingbach
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