英语听力文摘 English Digest 733 寄生蝇的耳朵给人类的启示（在线收听）

What We Can Learn From A Fly’s Ears

This may come as a surprise to you, but most flies don’t have the ability to hear. However, certain parasitic flies have a hearing system that is so exact in pinpointing a sound’s origin that it rivals the exceptional ears of owls and cats.

This fly’s superb hearing surprised scientists because its tiny body is too small to use the same kind of hearing system that larger animals use. And yet they discovered that the fly was using its hearing to locate the chirps of crickets in order to then deposit parasitic larvae onto the crickets’ bodies.

What they found was unlike any other known ear structure, this fly’s eardrums are connected by a bridge of stiff material. Vibrations that travel between the two eardrums enable the fly to pinpoint the origin of a sound as accurately as any other sound system we know of.

And what’s more, this fly’s exceptional hearing system is influencing microphone and hearing aid technology. For instance, it could lead to hearing aids that hide within a person’s ear canal and yet are able to gather sound primarily from the direction the listener is facing.

这可能会让你大吃一惊，但大多数苍蝇都没有听力。然而，某些寄生苍蝇的听觉系统非常精确地定位声音的来源，足以与猫头鹰和猫的特殊耳朵媲美。

这只苍蝇高超的听觉让科学家们感到惊讶，因为它小小的身体太小，无法使用大型动物所使用的那种听觉系统。然而，他们发现，这只苍蝇利用它的听觉来定位蟋蟀的叫声，以便将寄生幼虫沉积到蟋蟀的身体上。

他们发现，与其他已知的耳朵结构不同，这只苍蝇的耳膜是由坚硬的材料连接起来的。在两个耳膜之间传播的振动使苍蝇能够像我们所知的任何其他声音系统一样准确地定位声音的来源。

更重要的是，这只苍蝇独特的听觉系统正在影响麦克风和助听器技术。例如，这可能会导致助听器隐藏在人的耳道内，但能够主要从听众所面对的方向收集声音。