Data from: Beyond the limits: identifying the high-frequency detectors in the anuran ear

Despite the predominance of low-frequency hearing in anuran amphibians, a few frog species have evolved high-frequency communication within certain environmental contexts. Huia cavitympanum is the most remarkable anuran with regard to upper frequency limits; it is the first frog species known to emit exclusively ultrasonic signals. Characteristics of the Distortion Product Otoacoustic Emissions from the amphibian papilla and the basilar papilla were analysed to gain insight into the structures responsible for high-frequency/ultrasound sensitivity. Our results confirm the matching of vocalization spectra and inner ear tuning in this species. Compared to most anurans, H. cavitympanum has a hyperextended hearing range spanning from audible to ultrasonic frequencies, far above the previously established “spectral limits” for the amphibian ear. The exceptional high-frequency sensitivity in the inner ear of H. cavitympanum illustrates the remarkable plasticity of the auditory system and the extent to which evolution can modify a sensory system to adapt it to its environment.

尽管无尾两栖类（anuran amphibians）的听觉以低频感知占主导，但部分蛙类已在特定环境背景下演化出高频通信行为。阔褶水蛙（Huia cavitympanum）就高频上限而言是最具代表性的无尾两栖类，它是首个被证实仅能发出超声信号的蛙类物种。本研究针对两栖类乳头（amphibian papilla）与基底乳头（basilar papilla）的畸变产物耳声发射（Distortion Product Otoacoustic Emissions）特征展开分析，以解析介导高频/超声感知的耳部结构。我们的研究结果证实，该物种的发声频谱与内耳调谐特性高度匹配。与多数无尾两栖类相比，H. cavitympanum拥有超宽的听觉范围，覆盖可听声至超声频段，远超此前认定的两栖类耳部"spectral limits"。该物种内耳中非凡的高频感知能力，彰显了听觉系统极强的可塑性，也展现了演化可在多大程度上改造感官系统以适应其生存环境。