Martínez-Rivera Carlos César, Gerhardt H Carl
Division of Biological Sciences, University of Missouri-Columbia.
Behav Ecol Sociobiol. 2008;63(2):195-208. doi: 10.1007/s00265-008-0650-0.
Senders and receivers influence dynamic characteristics of the signals used for mate attraction over different time scales. On a moment-to-moment basis, interactions among senders competing for a mate influence dynamic characteristics, whereas the preferences of receivers of the opposite gender exert an influence over evolutionary time. We observed and recorded the calling patterns of the bird-voiced treefrog Hyla avivoca, to assess how the dynamic characters of calls vary during interactions among groups of males in a chorus. This question was also addressed using playback experiments with males. Playback experiments with females showed how changes in dynamic call properties are likely to affect male mating success. Frogs calling in pairs, groups, or in response to playbacks produced longer calls than did isolated males. During call overlap, males often increased the duration of the silent interval (gaps) between the pulses of their calls so that the pulses of the calls of two neighbors interdigitated. This change resulted in increased variability of pulse rate, a traditionally static acoustic property; however, males also produced high proportions of non-overlapped calls in which variability in pulse rate was low and had species-typical values. Females preferred long calls to short and average-duration calls, and non-overlapped calls to overlapped calls. Given a choice between pairs of overlapped calls, females preferred pairs in which the proportion of overlap was low and pairs in which the pulses of such calls interdigitated completely. The observed patterns of vocal competition thus reflect the preferences of conspecific females, which have influenced the evolution of the calling behavior of H. avivoca.
信号发送者和接收者会在不同时间尺度上影响用于配偶吸引的信号的动态特征。在瞬间尺度上，争夺配偶的发送者之间的相互作用会影响动态特征，而异性接收者的偏好则在进化时间尺度上发挥作用。我们观察并记录了鸟鸣树蛙（Hyla avivoca）的鸣叫模式，以评估在合唱中雄性群体间的相互作用过程中鸣叫的动态特征是如何变化的。这个问题也通过对雄性进行回放实验来探讨。对雌性进行的回放实验表明，鸣叫动态特性的变化可能如何影响雄性的交配成功率。成对、成群鸣叫或对回放做出反应的青蛙发出的叫声比单独鸣叫的雄性青蛙发出的叫声更长。在叫声重叠期间，雄性青蛙常常会增加其叫声脉冲之间静音间隔（间隙）的时长，以便相邻两只青蛙叫声的脉冲相互交错。这种变化导致脉冲率的变异性增加，而脉冲率是一种传统上被视为静态的声学特性；然而，雄性青蛙也会发出高比例的非重叠叫声，其中脉冲率的变异性较低且具有物种典型值。雌性更喜欢长叫声而非短叫声和平均时长的叫声，更喜欢非重叠叫声而非重叠叫声。在成对的重叠叫声中进行选择时，雌性更喜欢重叠比例低且叫声脉冲完全交错的成对叫声。因此，观察到的发声竞争模式反映了同种雌性的偏好，而这种偏好影响了鸟鸣树蛙鸣叫行为的进化。
