Weaver Savannah J, Callaghan Corey T, Rowley Jodi J L
Australian Museum Research Institute Australian Museum Sydney NSW Australia.
Department of Biology Bucknell University Lewisburg PA USA.
Ecol Evol. 2020 Oct 6;10(21):12115-12128. doi: 10.1002/ece3.6833. eCollection 2020 Nov.
Many animals rely on vocal communication for mating advertisement, territorial displays, and warning calls. Advertisement calls are species-specific, serve as a premating isolation mechanism, and reinforce species boundaries. Nevertheless, there is a great deal of interspecific variability of advertisement calls. Quantifying the variability of calls among individuals within a species and across species is critical to understand call evolution and species boundaries, and may build a foundation for further research in animal communication. However, collecting a large volume of advertisement call recordings across a large geographic area has traditionally posed a logistical barrier. We used data from the continental-scale citizen science project FrogID to investigate the spatial and temporal patterns of call characteristics in six Australian frog species. We found intraspecific call variability in both call duration and peak frequency across species. Using resampling methods, we show that variability in call duration and peak frequency was related to the number of individuals recorded, the geographic area encompassed by those individuals, and the intra-annual time difference between those recordings. We conclude that in order to accurately understand frog advertisement call variation, or "anuran accents," the number of individuals in a sample must be numerous ( ≥ 20), encompass a large geographic area relative to a species' range, and be collected throughout a species' calling season.
许多动物依靠声音交流来进行求偶广告、领地展示和发出警报。求偶叫声具有物种特异性，是一种交配前的隔离机制，并强化了物种界限。然而，求偶叫声存在大量种间变异性。量化一个物种内个体之间以及不同物种之间叫声的变异性对于理解叫声进化和物种界限至关重要，并且可能为动物交流的进一步研究奠定基础。然而，传统上在大地理区域收集大量求偶叫声录音存在后勤障碍。我们使用来自大陆规模公民科学项目FrogID的数据，研究了六种澳大利亚蛙类叫声特征的时空模式。我们发现所有物种在叫声持续时间和峰值频率上都存在种内叫声变异性。使用重采样方法，我们表明叫声持续时间和峰值频率的变异性与记录的个体数量、这些个体所涵盖的地理区域以及这些录音之间的年内时间差有关。我们得出结论，为了准确理解蛙类求偶叫声的变化，即“无尾类口音”，样本中的个体数量必须足够多（≥20），相对于物种分布范围涵盖较大的地理区域，并且要在一个物种的整个鸣叫季节进行收集。
