ABSTRACT

Anuran advertisement calls play a fundamental role in social interactions related to reproduction, like territory defence and mate attraction. As such, advertisement calls are often shaped by natural and sexual selection. Therefore, to understand the evolution, function, and mechanisms of signal production and perception, it is important to characterise sources and patterns of variation in call properties. We recorded and analysed the two types of advertisement calls produced by Pacific tree frogs, Hyliola regilla: diphasic and monophasic calls. Specifically, we examined (i) the relationship between call properties and both body size and physical condition, (ii) patterns of within- and among-individual variation in call properties, and (iii) acoustic differences between diphasic and monophasic calls. While only one property of diphasic calls correlates with physical condition, spectral properties of both types of calls correlate with body size. Patterns of within- and among-individual variation were similar between call types and, overall, consistent with patterns reported for closely related species. Monophasic calls have lower frequencies, are delivered faster, and have higher call effort and duty cycle than diphasic calls. We discuss our results in relation to sexual selection and formulate hypotheses about the evolution, function, and mechanisms of acoustic communication in Pacific tree frogs.

摘要

Anuran 广告呼叫在与繁殖相关的社会互动中发挥着重要作用，例如领土防御和配偶吸引。因此，广告呼叫通常受自然选择和性选择的影响。因此，要了解信号产生和感知的演变、功能和机制，表征呼叫特性变化的来源和模式非常重要。我们记录并分析了太平洋树蛙Hyliola regilla产生的两种广告呼叫: 双相和单相调用。具体而言，我们检查了 (i) 呼叫特性与身体大小和身体状况之间的关系，(ii) 呼叫特性的个体内部和个体间变化模式，以及 (iii) 双相和单相呼叫之间的声学​​差异。虽然双相呼叫的只有一种特性与身体状况相关，但两种类型的呼叫的频谱特性都与体型相关。个体内部和个体间变异的模式在呼叫类型之间相似，并且总体上与密切相关物种报告的模式一致。与双相呼叫相比，单相呼叫频率更低，传送速度更快，呼叫工作量和占空比更高。我们讨论了与性选择相关的结果，并提出了关于进化、功能、