Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
Department of Physics and Astronomy, Northwestern University, Evanston, IL 60208, USA; Department of Organismal Biology and Anatomy, University of Chicago, Chicago, IL 60637, USA.
Curr Biol. 2019 Feb 18;29(4):709-714.e4. doi: 10.1016/j.cub.2019.01.026. Epub 2019 Feb 7.
Mating behavior in Aedes aegypti mosquitoes occurs mid-air and involves the exchange of auditory signals at close range (millimeters to centimeters) [1-6]. It is widely assumed that this intimate signaling distance reflects short-range auditory sensitivity of their antennal hearing organs to faint flight tones [7, 8]. To the contrary, we show here that male mosquitoes can hear the female's flight tone at surprisingly long distances-from several meters to up to 10 m-and that unrestrained, resting Ae. aegypti males leap off their perches and take flight when they hear female flight tones. Moreover, auditory sensitivity tests of Ae. aegypti's hearing organ, made from neurophysiological recordings of the auditory nerve in response to pure-tone stimuli played from a loudspeaker, support the behavioral experiments. This demonstration of long-range hearing in mosquitoes overturns the common assumption that the thread-like antennal hearing organs of tiny insects are strictly close-range ears. The effective range of a hearing organ depends ultimately on its sensitivity [9-13]. Here, a mosquito's antennal ear is shown to be sensitive to sound levels down to 31 dB sound pressure level (SPL), translating to air particle velocity at nanometer dimensions. We note that the peak of energy of the first formant of the vowels of the human speech spectrum range from about 200-1,000 Hz and is typically spoken at 45-70 dB SPL; together, they lie in the sweet spot of mosquito hearing. VIDEO ABSTRACT.
埃及伊蚊的交配行为发生在半空中，涉及近距离（毫米到厘米）交换听觉信号[1-6]。人们普遍认为，这种亲密的信号距离反映了它们触角听觉器官对微弱飞行音的短距离听觉灵敏度[7,8]。相反，我们在这里表明，雄性蚊子可以在惊人的远距离听到雌性的飞行音-从几米到 10 米远-而且未受限制的、静止的埃及伊蚊雄性在听到雌性飞行音时会从栖木上跳下来并飞走。此外，对埃及伊蚊听觉器官的听觉敏感性测试，是通过响应来自扬声器播放的纯音刺激的听觉神经的神经生理学记录来进行的，这支持了行为实验。蚊子的远距离听觉能力的证明推翻了一个常见的假设，即微小昆虫的线状触角听觉器官是严格的近距离耳朵。听觉器官的有效范围最终取决于其灵敏度[9-13]。在这里，展示了蚊子的触角耳朵对低至 31 分贝声压级（SPL）的声音水平敏感，这相当于纳米级别的空气粒子速度。我们注意到，人类语音频谱的第一个共振峰的能量峰值范围约为 200-1000 Hz，通常以 45-70 dB SPL 说话；它们共同处于蚊子听觉的最佳范围。视频摘要。
