Department Biology II, Ludwig Maximilians University Munich, Martinsried, Germany.
Neurogenetics of Vocal Communication Group, Max Planck Institute for Psycholinguistics, Nijmegen, The Netherlands.
Proc Biol Sci. 2021 Jan 13;288(1942):20202600. doi: 10.1098/rspb.2020.2600. Epub 2021 Jan 6.
Differences in auditory perception between species are influenced by phylogenetic origin and the perceptual challenges imposed by the natural environment, such as detecting prey- or predator-generated sounds and communication signals. Bats are well suited for comparative studies on auditory perception since they predominantly rely on echolocation to perceive the world, while their social calls and most environmental sounds have low frequencies. We tested if hearing sensitivity and stimulus level coding in bats differ between high and low-frequency ranges by measuring auditory brainstem responses (ABRs) of 86 bats belonging to 11 species. In most species, auditory sensitivity was equally good at both high- and low-frequency ranges, while amplitude was more finely coded for higher frequency ranges. Additionally, we conducted a phylogenetic comparative analysis by combining our ABR data with published data on 27 species. Species-specific peaks in hearing sensitivity correlated with peak frequencies of echolocation calls and pup isolation calls, suggesting that changes in hearing sensitivity evolved in response to frequency changes of echolocation and social calls. Overall, our study provides the most comprehensive comparative assessment of bat hearing capacities to date and highlights the evolutionary pressures acting on their sensory perception.
物种间听觉感知的差异受到系统发育起源和自然环境带来的感知挑战的影响，例如探测猎物或捕食者发出的声音以及通讯信号。蝙蝠非常适合进行听觉感知方面的比较研究，因为它们主要依靠回声定位来感知世界，而它们的社交叫声和大多数环境声音的频率都较低。我们通过测量 11 种蝙蝠属的 86 只蝙蝠的听觉脑干反应（ABR）来测试蝙蝠在高频和低频范围内的听力灵敏度和刺激水平编码是否存在差异。在大多数物种中，高频和低频范围的听觉灵敏度都一样好，而高频范围的振幅编码则更为精细。此外，我们通过将 ABR 数据与 27 种物种的已发表数据相结合，进行了系统发育比较分析。听力灵敏度的种特异性峰值与回声定位叫声和幼崽隔离叫声的峰值频率相关，表明听力灵敏度的变化是对回声定位和社交叫声频率变化的进化响应。总的来说，我们的研究提供了迄今为止对蝙蝠听力能力最全面的比较评估，并强调了作用于它们感官感知的进化压力。
