Flies are arguably one of the least liked members of the animal kingdom. Their keen taste for organic waste, irritating buzzing sound, and proneness for carrying really undesirable bacteria has put them pretty close to the bottom of most people’s favorite animal list. However, their newest contribution to the science of hearing may make you rethink the fly’s reputation just a little.
The yellow-colored O. ochracea fly, native to the southern U.S. and Mexico, has truly remarkable hearing. Their acute sense of sound is the result of their unique sound-processing mechanism, according to a press release. A team of researchers from the University of Texas at Austin have developed a tiny prototype device that aims to translate the fly’s impressive ear into a new generation of hypersensitive hearing aids. Neal Hall, an assistant professor in the Cockrell School of Engineering at UT Austin, believes this is a “big step forward towards commercialization of the technology.”
Why Is This Fly’s Hearing So Good?
Evolution has treated the fly well, bestowing the little insect with an unusual way to perceive the world around it. What humans and other mammals perceive as sound is actually the result of the finite speed of sound combined with the separation of our eyes. The O. ochracea is equipped with a tiny see-saw-like structure in its ear. The structure, although tiny in size, is solely responsible for the fly’s advanced hearing abilities. It allows the fly to locate the precise location of an unsuspecting cricket. This would be almost equivalent to a human feeling an earthquake and being able to discern the direction of the epicenter using their ear. However, Hall said that the O. orchracea fly’s hearing is even more precise than this.
The Hypersensitive Hearing Aid
Hall and his graduate students, Michael Kuntzman and Donghwan Kim, built a see-saw-like structure out of silicon, modeled after the fly’s unique physiological mechanism. The piezoelectric material in the device allows for the simultaneous measuring of flexing and rotation of the structure. This allows them to replicate the natural workings of the fly’s ear.
Currently only two percent of the U.S. population wears hearing aids, but it’s estimated that as many as 10 percent would benefit from wearing one, Hall explained. "Many believe that the major reason for this gap is patient dissatisfaction. Turning up the gain to hear someone across from you also amplifies all of the surrounding background noise — resembling the sound of a cocktail party," Hall added. According to the researcher, the new hearing aid would differ from current generations because it would only focus in on sounds important to the wearer.
The field of bio-inspired robotics is a booming field filled with equally bizarre and intriguing mechanisms inspired by natural science. The fly-ear inspired hearing aid is not alone in the category of new technology that has roots in insect anatomy. Leg control Network (LegConNet) is a robotic leg control scheme heavily inspired by the adaptable and flexible leg behavior of the cockroach. Even the pesky flea is getting in on the action, as a near-perfect rubber with a 98 percent level of resiliency has been modeled after the parasite.