School of Biological Sciences, University of Bristol, Bristol, UK.
Department of Life Sciences, Insect Division, Natural History Museum, London, UK.
Sci Rep. 2019 Feb 5;9(1):1444. doi: 10.1038/s41598-018-37812-z.
Emitting ultrasound upon hearing an attacking bat is an effective defence strategy used by several moth taxa. Here we reveal how Yponomeuta moths acquire sophisticated acoustic protection despite being deaf themselves and hence unable to respond to bat attacks. Instead, flying Yponomeuta produce bursts of ultrasonic clicks perpetually; a striated patch in their hind wing clicks as the beating wing rotates and bends. This wing structure is strikingly similar to the thorax tymbals with which arctiine moths produce their anti-bat sounds. And indeed, Yponomeuta sounds closely mimic such arctiine signals, revealing convergence in form and function. Because both moth taxa contain noxious compounds, we conclude they are mutual Müllerian acoustic mimics. Yponomeuta's perpetual clicking would however also attract bat predators. In response, their click amplitude is reduced and affords acoustic protection just as far as required, matching the distance over which bat biosonar would pick up Yponomeuta echoes anyway - advanced acoustic defences for a deaf moth.
听到攻击的蝙蝠发出超声波是几种蛾类使用的一种有效防御策略。在这里，我们揭示了 Yponomeuta 飞蛾如何在自身失聪的情况下获得复杂的声学保护，从而无法对蝙蝠的攻击做出反应。相反，飞行的 Yponomeuta 会不断地发出超声爆发；当拍打翅膀旋转和弯曲时，它们的后翼上有条纹的斑块会发出咔哒声。这种翅膀结构与 arctiine 飞蛾产生抗蝙蝠声音的胸部鼓膜非常相似。事实上，Yponomeuta 的声音非常类似于这种 arctiine 信号，揭示了形式和功能的趋同。因为这两个飞蛾类群都含有有毒化合物，我们得出结论，它们是相互 Müllerian 声学模拟物。然而，Yponomeuta 的持续咔哒声也会吸引蝙蝠捕食者。作为回应，它们的咔哒声幅度减小，并提供了所需的声学保护，与蝙蝠生物声纳无论如何都会接收到 Yponomeuta 回声的距离相匹配——这是一种为失聪的飞蛾提供的先进的声学防御。
