Gupta Saumya, Bee Mark A
Department of Ecology, Evolution, and Behavior, University of Minnesota, Twin Cities, 1479 Gortner Ave, Saint Paul, MN, 55108, USA.
Department of Biology, University of Washington, Box 351800, Seattle, WA, 98195, USA.
J Comp Physiol A Neuroethol Sens Neural Behav Physiol. 2023 Jan;209(1):31-45. doi: 10.1007/s00359-022-01575-w. Epub 2022 Oct 28.
Amphibians have inner ears with two sensory papillae tuned to different frequency ranges of airborne sounds. In frogs, male advertisement calls possess distinct spectral components that match the tuning of one or both sensory papillae. Female preferences for the spectral content of advertisement calls can depend on signal amplitude and can vary among closely related lineages. In this study of Cope's gray tree frog (Hyla chrysoscelis), we investigated the amplitude dependence of female preferences for the spectral content of male advertisement calls, which have a "bimodal" spectrum with separate low-frequency (1.25 kHz) and high-frequency (2.5 kHz) components. In two-alternative choice tests, females generally preferred synthetic calls with bimodal spectra over "unimodal" calls having only one of the two spectral components. They also preferred unimodal calls with a high-frequency component over one with the low-frequency component. With few exceptions, preferences were largely independent of amplitude across both a 30 dB range of overall signal amplitude and an 11 dB range in the relative amplitudes of the two spectral components. We discuss these results in the context of evolutionary lability in female preferences for the spectral content of advertisement calls in North American tree frogs in the genus Hyla.
两栖动物的内耳有两个感觉乳突，能适应不同频率范围的空气传播声音。在青蛙中，雄性求偶叫声具有独特的频谱成分，与一个或两个感觉乳突的调谐相匹配。雌性对求偶叫声频谱内容的偏好可能取决于信号幅度，并且在亲缘关系密切的谱系中会有所不同。在对科佩氏灰树蛙（雨蛙）的这项研究中，我们调查了雌性对雄性求偶叫声频谱内容偏好的幅度依赖性，这些叫声具有“双峰”频谱，有单独的低频（1.25千赫）和高频（2.5千赫）成分。在双选测试中，雌性通常更喜欢具有双峰频谱的合成叫声，而不是只有两个频谱成分之一的“单峰”叫声。它们也更喜欢具有高频成分的单峰叫声，而不是具有低频成分的单峰叫声。除了少数例外，在总信号幅度30分贝的范围内以及两个频谱成分相对幅度11分贝的范围内，偏好基本上与幅度无关。我们在北美雨蛙属树蛙雌性对求偶叫声频谱内容偏好的进化不稳定性背景下讨论这些结果。
