Scientists are studying how tobacco hornworm caterpillars, which do not have visible ears, can sense the presence of predators like wasps. A team of biologists and engineers is exploring the possibility that these caterpillars rely on tiny, supersensitive hairs on their bodies to detect sound. To better understand this ability, the researchers conducted experiments in an anechoic chamber—a specially designed, soundproof room that blocks all external noise and vibrations. In the chamber, the scientists placed the caterpillars on a platform and exposed them to controlled vibrations. They used an accelerometer to measure the vibrations and observed the caterpillars’ responses. The caterpillars reacted to vibrations only when they reached certain intensity levels. However, when the researchers used airborne sound instead of vibrations, the caterpillars responded even when the vibrations were below the previously measured threshold. This suggested that the caterpillars were directly detecting the airborne sound, not just the vibrations. To test the role of the tiny hairs, the researchers carefully removed some of them and observed how the caterpillars responded to sound. They found that removing certain hairs reduced the caterpillars’ ability to react to sounds, especially at specific frequencies. This indicates that the hairs may be specialized for detecting different sound frequencies, much like how human ears detect various pitches. The findings from this study could have practical applications in engineering. Traditional microphones detect sound based on changes in air pressure, but this research suggests that future microphone designs could use structures similar to the caterpillars’ hairs to detect air particle movement. This could lead to more precise directional sound detection, useful in areas such as hearing aids, surveillance, and communication devices.