Beckers Oliver M, Schul Johannes
Division of Biological Sciences, University of Missouri, 207 Tucker Hall, Columbia, MO 65211, USA.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2004 Nov;190(11):869-76. doi: 10.1007/s00359-004-0542-3. Epub 2004 Aug 14.
The influence of call amplitude on phonotaxis in female Hyla versicolor was studied using a no-choice paradigm. One set of experiments estimated effects of stimulus amplitude on phonotaxis toward a synthetic model of a conspecific call. The response strength increased with amplitude from the behavioral threshold (37-43 dB SPL) up to 79 dB SPL and then decreased at higher amplitudes. Females approached the loudspeaker with short walking bouts (approximately 1 s duration) occurring immediately after call presentations. Increase in response strength was attributed to an increasing proportion of calls that elicited such walking bouts, whereas the decrease at high amplitudes resulted from decreasing distance covered per bout. The quality of orientation remained constant for all above-threshold amplitudes. A second set of experiments tested the selectivity for interval duration and pulse duration at amplitudes of 55, 70, and 85 dB SPL. Selectivity for both parameters was similar at 70 and 85 dB SPL, but tended to increase at 55 dB SPL. The results suggest that selective phonotaxis in H. versicolor is not adapted for long-distance communication. This finding differs from those of comparable studies of acoustic insects.
使用无选择范式研究了叫声幅度对雌性变色雨蛙趋声性的影响。一组实验估计了刺激幅度对朝向同种叫声合成模型趋声性的影响。响应强度从行为阈值（37 - 43 dB SPL）开始随幅度增加，直至79 dB SPL，然后在更高幅度时下降。雌性在叫声呈现后立即以短时间行走回合（约1秒持续时间）接近扬声器。响应强度的增加归因于引发此类行走回合的叫声比例增加，而高幅度时的下降是由于每个回合覆盖的距离减少。对于所有高于阈值的幅度，定向质量保持恒定。第二组实验在55、70和85 dB SPL的幅度下测试了对间隔持续时间和脉冲持续时间的选择性。在70和85 dB SPL时，对这两个参数的选择性相似，但在55 dB SPL时趋于增加。结果表明，变色雨蛙的选择性趋声性不适合长距离通讯。这一发现与声学昆虫的类似研究结果不同。
