The Chirp of Crickets

There's no advantage to being a "fly on the wall" unless the fly can hear. Researchers have mimicked the hearing mechanism of the Ormia ochracea, a fly that is able to isolate the chirp of its prey, male crickets, with remarkable accuracy:

A tiny structure similar to a playground see-saw connects the fly's two sound sensors, and vibration on one side drives the other in the opposite direction. The net motion of the see-saw permits the fly to determine what is known as the "phase" of the sound wave—in other words, the extent to which the peaks and troughs of the sound waves detected by its sound sensors line up with each other. This allows for fantastically precise determination of its direction of origin.

Sensitive hearing aids that are able to ignore unwanted sounds will be the result of studying Ormia. That will be a boon to us aging, hard-of-hearing snoops who not only want to listen to gossip but help originate it.

Photos and diagrams from Washington University in St. Louis